Patent Application
20180354090
The present invention generally relates to machines configured to sharpen blades for ice skates. More particularly, the present invention relates to such machines configured for automated sharpening of blades for ice skates.
Ice skates engage the surface of the ice on a pair of edges. Over time, the edges can become dull or nicked and, in such conditions, the performance of the ice skates is less than optimal. To restore the performance of the ice skates, the skate blades can be sharpened.
While the frequency of ice skate blade sharpening differs depending upon the individual, the recommended frequency for most serious skaters is one sharpening for every three to five hours of ice time. When it is time for the sharpening, few people have the equipment necessary to sharpen the skates and, for that reason, the skates need to be dropped off at a local skate shop or ice rink for sharpening. The frequent trips for sharpening can become an annoyance and many skaters will skate on less than optimal skate blades simply to avoid the extra trips or time in line at the skate shop or rink. Even if people had access to the equipment, few people have the training or skills necessary to sharpen their own skates.
A need exists for skate sharpening machines that are simple to use and cost effective enough for home use. Certain features, aspects and advantages of the invention address a myriad of challenges encountered when designing a portable skate sharpening machine that is cost effective and easy to use.
Certain aspects of the disclosure provide a method of aligning a grinding component in a skate blade sharpening system. The method can include positioning a first visual reference feature at a first predetermined location relative to at least one jaw configured to secure a skate blade within the skate blade sharpening system; providing a second visual reference feature at a second predetermined location on a motor-driven component, wherein the motor-driven component is movable within a housing of the skate blade sharpening system by an adjustment mechanism; and operating the adjustment mechanism to position the motor-driven component such that the second visual reference feature is brought into alignment with the first visual reference feature thereby bringing into alignment the skate blade with the grinding component.
In some configurations, the first visual reference feature is positioned at a defined distance from a centerline of the at least one jaw when a skate blade is secured within the at least one jaw. In some configurations, the second visual reference feature is positioned at a defined distance from a centerline of a grinding portion of a grinding component when the grinding component is mounted on a mounting location of the motor-driven component. In some configurations, the centerline of the grinding component is at a maximum outer diameter of the grinding portion. In some configurations, the alignment of the second visual reference feature with the first visual reference feature aligns the centerline of the grinding component with a centerline of the skate blade. In some configurations, positioning the first visual reference feature at the first predetermined location includes temporarily securing the first visual reference feature within the housing of the skate blade sharpening system. In some configurations the method includes positioning a magnifying lens configured to magnify a view area of the first visual reference feature and the second visual reference feature. In some configurations, a grinding component is configured to be removably mounted on a mounting location of the motor-driven component without adjusting the alignment of the motor-driven component. In some configurations, the first visual reference feature is a flag-like structure. In some configurations, the second visual reference feature is incorporated into the motor-driven component. In some configurations, the second visual reference feature is positioned on an arbor coupled to the motor-driven component. In some configurations, the second visual reference feature is a notch recessed in an alignment component coupled to the motor-driven component. In some configurations, the alignment component has a noncircular shape. In some configurations, the second visual reference feature is on a grinding component coupled to the motor-driven component, wherein the grinding component comprises an alignment portion and a grinding portion, wherein the grinding portion comprises an abrasive outer layer. In some configurations, the second visual reference feature is a notch recessed in the alignment portion. In some configurations, operating the adjustment mechanism to position the motor-driven component such that the second visual reference feature is brought into alignment with the first visual reference feature is performed by a controller configured to control the operation of the adjustment mechanism. In some configurations, the method includes comprising positioning the motor-driven component in an alignment position within the housing of the skate blade sharpening system prior to alignment.
In another embodiment, a skate blade sharpening system includes a housing comprising at least one jaw configured to secure a skate blade; a motor-driven component configured to be movable within the housing of the skate blade sharpening system relative to the at least one jaw; a first visual reference feature positioned within the housing at a first predetermined location relative to the at least one jaw; a second visual reference feature positioned on the motor-driven component at a second predetermined location; and an adjustment mechanism configured to position the motor-driven component such that the second visual reference feature is brought into alignment with the first visual reference feature.
In some configurations, the second visual reference feature is positioned at a defined distance from a centerline of a grinding portion of a grinding component when the grinding component is mounted on a mounting location on the motor-driven component. In some configurations, the alignment of the second visual reference feature with the first visual reference feature aligns a centerline of the at least one jaw with the centerline of the grinding component when the grinding component is mounted to the mounting location. In some configurations, the second visual reference feature is positioned on an alignment component mounted on a mounting location on the motor-driven component. In some configurations, the second visual reference feature is incorporated into the motor-driven component. In some configurations, a grinding component is configured to be removably mounted on a mounting location of the motor-driven component without adjusting the alignment of the motor-driven component. In some configurations, the second visual reference feature is on a grinding component coupled to the motor-driven component, wherein the grinding component comprises an alignment portion and a grinding portion, wherein the grinding portion comprises an abrasive outer layer. In some configurations, the system includes a controller configured to control operation of the adjustment mechanism and automatically position the motor-driven component such that the second visual reference is brought into alignment with the first visual reference feature.
In another embodiment, a skate blade sharpening system includes a grinding component coupled to a motor for rotation, the grinding component configured to translate longitudinally relative to a bottom edge of a skate blade retained by the skate blade holder, the grinding component having an outer surface dimensioned and configured to sharpen the bottom edge of the skate blade during a sharpening operation, and the grinding component including an identification tag having interface circuitry configured to communicate with electronic circuitry of the skate blade sharpening system and memory including a usage location configured to store a usage tracking value. The skate sharpening can also include electronic circuitry that can include a transceiver configured to communicate with the interface circuitry of the identification tag and to read from and write to the usage location; sharpening control circuitry configured to control operation of the grinding component and perform sharpening operations; and usage control circuitry configured to write, using the transceiver, an update to the usage tracking value based, at least in part, on usage of the grinding component during sharpening operations; read, using the transceiver, a current usage tracking value from the usage location; and control operation of the sharpening control circuitry for sharpening operations based, at least in part, on the current usage tracking value.
In some configurations, the usage control circuitry is further configured to selectively enable or disable operation of the sharpening control circuitry for sharpening operations. In some configurations, the usage tracking value indicates usage of the grinding component as a number of passes performed by the grinding component during sharpening operations, wherein the electronic circuitry is configured to update the usage tracking value based, at least in part, on the number of passes performed by the grinding component. In some configurations, the usage location is further configured to store a usage limit value, the usage limit value indicates a maximum number of passes a grinding component can complete, wherein the grinding component includes a metal grinding ring having an outer surface with an abrasive layer thereon, the abrasive layer having a defined lifetime, and wherein the usage limit value corresponds to a period of use of the abrasive layer that is less than the defined lifetime of the abrasive layer. In some configurations, the usage control circuitry is further configured to determine whether a usage threshold of the grinding component has been satisfied based, at least in part, on a relationship between the current usage tracking value and the usage limit value. In some configurations, the memory of the identification tag is further configured to include one or more system setup parameter locations for storing system setup parameters, and wherein the interface circuitry is further configured to provide the system setup parameters from the system setup parameter locations to the electronic circuitry of the sharpening system to be applied to setup parameters of the sharpening system. In some configurations, the system setup parameters comprise operating parameters having determined values for the specific grinding component, wherein the operating parameters include one or more of a grinding motor rotation speed, a translation speed, or a normal grinding force. In some configurations, the memory of the identification tag is further configured to include one or more user setting locations for storing user-specific default settings for parameters of a sharpening operation, and wherein the interface circuitry is configured to provide the user-specific default settings to the electronic circuitry to be applied to control a sharpening operation. In some configurations, the memory of the identification tag is further configured to include one or more fault information locations for storing fault data describing one or more fault conditions occurring during a sharpening operation using the grinding component, the fault information locations being readable by a separate reader used in a fault diagnosis, and wherein the interface circuitry is configured to (i) receive from the electronic circuitry particular fault data identifying an occurrence of a particular fault during a sharpening operation, and (ii) write the particular fault data to the fault information locations. In some configurations, the interface circuitry provides a wireless interface for wireless communication between the transceiver and the identification tag. In some configurations, the identification tag is located within the grinding component such that the identification tag rotates with the grinding component during the sharpening operation, and wherein the interface circuitry is configured to engage in the wireless communication with the transceiver during the sharpening operation as the grinding component rotates. In some configurations, the grinding component includes a metallic ring having an abrasive-coated outer surface for contacting a blade to be sharpened during sharpening operations; and a generally disk-shaped hub carrying the identification tag and to which the metallic ring is fixedly mounted, the hub and ring being configured for mating with an arbor on a rotating shaft of the sharpening system. In some configurations, the metallic ring circumscribes a cylindrical region in which at least part of the hub is located, the cylindrical area extending between first and second axial ends of the metallic ring; the interface circuitry of the identification tag provides a wireless interface for wireless communication between the transceiver and the identification tag; and the identification tag is mounted to the hub in a manner to reduce an effect of the metallic ring on the wireless communication between the transceiver and the identification tag. In some configurations, the grinding component is a grinding wheel. In some configurations, the grinding component includes a hub of a non-metallic material, the hub carrying the identification tag. In some configurations, an axial end of the hub includes a user-inaccessible covered cavity in which the identification tag is located.
In another embodiment, a method of operating a skate blade sharpening system can include performing at least one sharpening operation with a grinding component using the skate blade sharpening system, wherein a motor-driven component housed within the skate blade sharpening system translates the grinding component longitudinally along a bottom edge of a skate blade retained by a skate blade holder, the grinding component having an outer surface dimensioned and configured to sharpen the bottom edge of the skate blade, and the grinding component including an identification tag having interface circuitry configured to communicate wirelessly and memory including a usage location configured to store a usage tracking value; communicating, using a transceiver of the skate blade sharpening system, with the interface circuitry of the identification tag to write an updated usage tracking value to the usage location based, at least in part, on usage of the grinding component during the at least one sharpening operation, communicating, using the transceiver, with the interface circuitry of the identification tag to read the updated usage tracking value from the usage location, and controlling operation of the sharpening control circuitry for sharpening operations based, at least in part, on the updated usage tracking value.
In some configurations, controlling operation of the sharpening control circuitry comprises enabling or disabling operation of the sharpening control circuitry. In some configurations, usage of the grinding component during the at least one sharpening operation comprises a number of passes performed by the grinding component during the sharpening operation, and the updated usage tracking value is based, at least in part, on the number of passes performed by the grinding component during the at least one sharpening operation. In some configurations, controlling operation of the sharpening control circuitry for sharpening operations is based, at least in part, on the updated usage tracking value further includes comparing the updated usage tracking value to a usage limit value stored in the usage location of the identification tag, wherein the usage limit value indicates a maximum number of passes a grinding component can complete; and determining whether a usage threshold of the grinding component has been exceeded based, at least in part, on a relationship between the updated usage tracking value and the usage limit value. In some configurations, the can include, prior to performing the at least one sharpening operation, communicating with the identification tag to access at least one system setup parameter; and configuring the skate blade sharpening system in accordance with the at least one setup parameter. In some configurations, the method can include, prior to performing the at least one sharpening operation, communicating with the identification tag to access at least one operating parameter associated with the operation of the grinding component; and performing the at least one sharpening operation with the grinding component in accordance with the at least one operating parameter. In some configurations, the method can include, prior to performing the at least one sharpening operation, communicating with the identification tag to access at least one user-specific default setting for parameters of the sharpening operation; and performing the at least one sharpening operation with the grinding component in accordance with the at least one user-specific default setting for parameters of the sharpening operation.
In another embodiment, a skate blade sharpening system can include a housing having a slot configured to receive a skate blade in a sharpening position; a grinding component configured for movement along the slot at a lower edge of the skate blade during a sharpening operation; at least one slot cover movable between an occluding position and a non-occluding position along the slot; at least one sensing component configured to determine engagement of the at least one slot cover with the skate blade; wherein in the non-occluding position the at least one slot cover permits insertion and removal of the skate blade, wherein in the occluding position the at least one slot cover engages at least one end of the skate blade and limits access through at least a portion of the slot; and a controller of the skate blade sharpening system configured to control operation of the grinding component based, at least in part, on at least one indication received from the at least one sensing component.
In some configurations, the controller is further configured to prevent a sharpening operation based, at least in part, on an indication received from the at least one sensing component that the at least one slot cover is positioned in the non-occluding position. In some configurations, the skate blade sharpening system can include a dust pan switch configured to determine whether a dust pan is positioned within the chassis of the skate blade sharpening system, wherein the controller is further configured to prevent operation of the skate blade sharpening system when the dust pan is not positioned within the chassis. In some configurations, the skate blade sharpening system can include a door configured to provide access to an interior of the chassis and a door switch configured to determine whether the door is in an open position or a closed position, wherein the controller is further configured to prevent operation of the skate blade sharpening system when the door is in the open position. In some configurations, the skate blade sharpening system can include a lighting component configured to provide a visual indication indicative of an operational state of the skate blade sharpening system. In some configurations, the lighting component is configured to provide different visual indications for different operational states. In some configurations, the lighting component is a light-emitting diode. In some configurations, the at least one sensing component is included in the at least one slot cover. In some configurations, the at least one sensing component includes a mechanical member moving between a first position and a second position, the mechanical member configured to be in the first position when the at least one slot cover is not engaged by the skate blade, the mechanical member configured to be in the second position when the at least one slot cover is engaged by the skate blade. In some configurations, the mechanical member includes a switch-engaging portion, wherein the at least one sensing component further includes an electrical switch engaged by the switch-engaging portion when the mechanical member is in the first position, and the indication provided by the at least one sensing component indicates an electrical state of the electrical switch. In some configurations, in the first position, the indication provided by the at least one sensing component is an open electrical state, and in the second position, the indication provided by the at least one sensing component is a closed electrical state. In some configurations, the mechanical member is a bumper having a face portion configured to be pushed by the skate blade to move the bumper from the first position to the second position. In some configurations, the at least one slot is positioned on top of the housing. In some configurations, the grinding component is a grinding wheel.
In another embodiment, a method of operating a skate blade sharpening system can include receiving, by a controller, an indication from a sensing component of a position of at least one slot cover, wherein the at least one slot cover is mounted relative to a slot of a housing, the slot configured to receive a skate blade in a sharpening position, the at least one slot cover movable between an occluding position and a non-occluding position along the slot, wherein a grinding component is positioned within the housing and configured for movement along the slot at a lower edge of the skate blade during a sharpening operation; determining, by the controller, whether the at least one slot cover is positioned in the occluding position based, at least in part, on the indication from the sensing component, wherein in the non-occluding position the at least one slot cover permits insertion and removal of the skate blade, wherein in the occluding position the at least one slot cover is engaged with at least one end of the skate blade and limits access through at least a portion of the slot during the sharpening operation; and based on a determination that the at least one slot cover is positioned in the non-occluding position, preventing initiation of the sharpening operation.
In some configurations, based on a determination that the at least one slot cover is positioned in the occluding position, initiating a sharpening operation; receiving an indication during the sharpening operation that the at least one slot cover is positioned in the non-occluding position; and stopping operation of the sharpening operation based, at least in part, on the indication. In some configurations, the method can include determining whether a dust pan is positioned within the chassis of the skate blade sharpening system based, at least in part, on an indication received from a dust pan switch; and preventing operation of the sharpening operation when the dust pan is not positioned within the chassis. In some configurations, the method can include determining whether a door is in an open position or a closed position based, at least in part, on an indication received from a door switch, wherein the door provides access to an interior of the chassis; and preventing operation of the sharpening operation when the door is in the open position. In some configurations, the method can include determining whether a filter element is positioned within the chassis of the skate blade sharpening system based, at least in part, on an indication received from a filter switch; and preventing operation of the sharpening operation when the filter is not positioned within the chassis. In some configurations, the method can include outputting a visual indication from at least one light component indicating that the skate blade sharpening system will not operate based, at least in part, on at least one of an indication that the at least on slot cover is not engaged with the skate blade, an indication that the dust pan is not positioned within the chassis, an indication that the door is in an open position, or an indication that the filter element is not positioned within the chassis. In some configurations, the method can include the visual indication is configured to direct a user to a component of the skate sharpening system that requires attention.
These and other features, aspects, and advantages will be apparent from the following description of particular embodiments, as illustrated in the accompanying drawings in which like reference characters refer to the same parts throughout the different views.
The illustrated skate sharpener 10 has a box-like housing with structural elements including a rigid frame 12 (bottom visible in
Returning to
The above operation may also be used with bare removable skate blades of the type known in the art. In this case a blade holder or other mechanical aid of some type may be used to enable a user to position the bare blade in the slot 24 for clamping and to engage the bumpers 29 of the scoops 28 to permit operation. For example, the blade may be secured in a blade holder such as that described in co-pending U.S. patent application Ser. No. 14/632,862, filed Feb. 26, 2015, and U.S. patent application Ser. No. 14/632,868, filed Feb. 26, 2015, both of which are hereby incorporated by reference in their entirety. Alternatively, a bare blade could also be positioned without a blade holder. As described more below, a blade holder may engage limit switches on the slot covers 28 to enable sharpening operation, and enables a user to insert a loose skate blade in clamping jaws.
As shown, the chassis 14 has an S-like cross section defining the frontward platform 22 and a rearward shelf portion (“shelf”) 56 separated by a sloping wall 58. The underside of the shelf 56 includes two rails 60 on which a carriage (not shown) moves, as well as a downward-projecting flange 62. As described more below, a toothed “gear rack” that forms part of a rack-and-pinion mechanism for moving the carriage is attached to the flange 62. On the platform 22 at each end of the slot 24 are rounded projections 64 on which the scoops 28 are slidably mounted. The projections 64, also referred to as “arches” 64 below, have retention grooves 66 that engage with corresponding features in the scoops 28 to retain the scoops 28 on the projections 64 while permitting them to slide left and right.
One important feature of the presently disclosed skate sharpener 10 is use of a compact (small-diameter) grinding wheel 36. Specifically, its diameter is less than the diameter of the grinding wheel motor 80 by which it is rotated. Use of a compact grinding wheel 36 can provide certain advantages including greater precision in operation and lower cost.
Also shown in schematic fashion in
In operation, the grinding wheel 36 is rotated by the grinding wheel motor 80 via the spindle 82, and the carriage assembly 70 is moved back and forth along the rails 60 by action of a rack-and-pinion mechanism that includes a motor-drive pinion gear 87 engaging a toothed rack on the underside of the chassis 14 (described more below). The pinion gear 87 is driven by a carriage motor mounted within the carriage 72, not visible in
As shown, the jaws 90 each include angled slots 104, and in the slots 104 are arranged rectangular guide blocks 106 that retain the jaws 90 at the underside of the platform 22 with spacing to permit the jaws 90 to slide in the long direction of the slots 104. The front jaw 90-F is retained by one guide block 107 in a center slot 104, while the rear jaw 90-R is retained by respective guide blocks 106 in outer two slots 104. This arrangement permits the front jaw 90-F to rotate very slightly about a Z-direction axis extending through the single guide block 106, while the rear jaw 90-F is rotationally fixed. Additional details are provided below.
When the clamp paddle 26 is in the position shown in both
When a skate blade is to be clamped for sharpening, a user rotates the clamp paddle 26 to open the jaws 90. Referring to
The jaw guard 100 protects against the possibility of contact between the grinding wheel 36 and the jaws 90. If the sharpener 10 were to somehow be operated without a skate blade present, then without the jaw guard 100 the wheel 36 would move across the jaws 90 at its upper vertical limit position, potentially damaging the grinding wheel 36 and/or the jaws 90. The likelihood of this occurring can be reduced or eliminated by the jaw guard 100, which would be encountered by the spindle 82 (
Also shown in
Both the controllers 132 and processor 130 are computerized devices including memory, I/O interface circuitry and instruction processing circuitry for executing computer program instructions stored in the memory. The controllers 132 may be specialized for low-level real-time control tasks such as achieving and maintaining a commanded rotational speed for a motor. The processor 130 may have a more generalized architecture and potentially richer set of programming resources to perform a variety of higher-level tasks, including interfacing to a user via the UI display panel 34. The processor 130 executing instructions of a particular computer program may be viewed as circuitry for performing functions defined by the program. For example, the processor executing instructions of a sharpening operation controller may be referred to as sharpening control circuitry, and the processor executing instructions related to usage control may be referred to as usage control circuitry. As mentioned above with reference to
The grinding ring 200 has an abrasive outer surface for removing material from a skate blade during operation. In one embodiment the abrasive surface may include a diamond or cubic boron nitride (CBN) coating, deposited by electroplating for example. The grinding ring 200 is preferably of steel or similar rigid, strong metal, and it may be fabricated from steel tubing or bar stock. Although in general the grinding ring 200 may be of any size, it is preferably less than about 100 mm in diameter and even more preferably less than about 50 mm in diameter. Its thickness (radially) is substantially less than its radius, e.g., by a ratio of 1:4 or smaller. The ring shape, as opposed to a disk shape as used in more conventional grinding wheel designs, produces a much lighter grinding wheel 36 which can reduce the effects of wheel imbalance, eccentricity, and non-planarity. Reducing such effects can contribute to a smoother finish on a skate blade and a higher performance skate sharpening.
As shown, both the arbor 212 and hub 202 have shaped outer edges which mate with respective edges of the grinding ring 200. The mating between the arbor 212 and ring 200 is a sliding contact mating that permits mounting and dismounting of the grinding wheel 36 while also providing for heat transfer between the grinding ring 200 and the arbor 212. This relatively tight fit is also responsible for the centering of the grinding wheel. The heat transfer helps dissipate frictional heat generated in the grinding ring 200 as it rotates against a skate blade in operation. Specifically this mating is between a portion of an inner annular surface of the grinding ring 200 and an annular outer rim of the arbor 212. Both the hub 202 and arbor 212 have notches or shoulders on which respective portions of the grinding ring 200 rest. Thus the shoulder portion of the hub 202 extends only partway into the grinding ring 200, so that a remaining part of the grinding ring 200 extends beyond the arbor-facing end of the hub 202 and mates with the shoulder portion of the arbor 212.
The arbor 212 may include vanes or other features to increase its surface area and/or enhance air flow for a desired cooling effect, further promoting heat dissipation and helping to maintain a desired operating temperature of the grinding ring 200 in operation.
One important feature of the grinding ring 200 is its relatively small size, as compared to conventional grinding wheels which may be several inches in diameter for example. Both the small size of the ring (outer diameter) as well as its ring geometry (in contrast to disk geometry of conventional grinding wheels) contribute to advantages as well as challenges. Advantages include low cost and ease of manufacture, so that it can be easily and inexpensively replaced to maintain high-quality sharpening operation. The size and geometry also reduce any contribution of the grinding ring 200 to imbalance and related mechanical imperfections of operation. Balance and related operational characteristics are more heavily influenced by the arbor 212, which is preferably precision-formed and precision-mounted. One challenge of the geometry and size of the grinding ring 200 is heat removal, and this is addressed in part by the heat-conducting mating with the arbor 212 and heat-dissipating features of the arbor 212.
The identification tag 204 has a unique identifier such as a manufacturer's serial number, and when packaged with a grinding wheel 36 into an assembly serves to uniquely identify that assembly including the constituent grinding wheel 36. The identification tag 204 also includes memory capable of persistently storing data items, used for any of a variety of functions such as described further below. The identification tag preferably employs a security mechanism to protect itself against tampering and improper use, including improper manipulation of the contents of the memory. Memory protected in such a manner may be referred to as “secure memory”. The serial number should be a read-only value, while the memory is preferably both readable and writeable. As described below, a separate transceiver in the system 10 is capable of exchanging communication signals with the tag 204 for reading and writing data. In one embodiment, so-called “RFID” or radio frequency identification techniques may be employed. Using RFID, the identification tag 204 is read from and written to using radio-frequency electromagnetic waves by an RFID transceiver contained in the sharpening system 10 (described more below). Other types of implementations are possible, including optically interrogated tags and contact-based tags such as an iButton® device.
For security, the identification tag 204 may use an access code that is read by the control unit 32 and validated. The access code can be generated by a cryptographic hash function or other encryption algorithm that takes as input the serial number of the identification tag 204 and a confidential hash key. Using the serial number ensures that the access code created is uniquely paired with a specific identification tag 204. This uniqueness can help reduce or eliminate the likelihood of misuse that is attempted by copying an access code from one identification tag 204 to another. When the serial number of the other identification tag 204 is encrypted, the result will not match the copied access code, and appropriate action can be taken such as reducing or eliminating the likelihood of use of the grinding wheel 36 that contains the apparently fraudulent identification tag 204.
With reference now to
Other shapes for the antenna and other locations are possible. For example, the antenna could be located behind the grinding wheel 1036 when the grinding wheel 1036 is in the home position such that a user would see the grinding wheel 1036 and the grinding wheel would obscure at least a portion of the antenna or the housing 1220 containing the antenna or the like. In some configurations, the sensor module 1222 could be positioned in a different location within the skate sharpener 1010. For example, the sensor module 1222 could be positioned at the opposite end of the sharpening pass or at another location along the sharpening pass. In some configurations, the sensor module 1222 could be positioned between the two ends of the sharpening pass. In some configurations, the sensor module 1222 could be positioned within a region bounded by the ends of the jaws of the clamps such that any time the grinding wheel 1036 made a full sharpening pass, the grinding wheel 1036 would pass through a region containing the sensor module 1222 (even if the grinding wheel 1036 did not move all the way to the home position).
In the illustrated configuration, the circular shape of the antenna provides a central area of the circuit board that can be removed without adversely impacting communication performance. The housing 1220 that encloses the sensor module 1222 also can include an opening 1223. Because the home position for a grinding wheel 1036 in the currently configuration is within a region including the housing 1220 (e.g., the read/write region), the grinding wheel 1036, when in the home position, would generally be obscured by the housing 1220. As shown in
While the illustrated opening 1223 of the housing 1220 is concentric with the grinding wheel 1036 in the home position, the opening 1223 could have other configurations keeping in mind a desire to view at least a portion of the grinding wheel 1023 through the opening 1223. For example, the opening 1223 could be smaller but overlap a portion of the grinding wheel 1036 such that the opening 1223 provides a user the ability to determine the variety of grinding wheel 1036 installed. In some configurations, the opening 1223 is a window and has a covering such as a light transmissive or light transparent covering. In the illustrated configuration, however, the opening 1223 is not covered and allows physical access to the grinding wheel 1036.
As mentioned above, the wheel 36 includes an identification tag 204 on which various data may be stored for a variety of purposes. In the illustrated embodiment this tag employs a wireless communication technique such as Radio Frequency Identification (RFID) communications. The sensor module 222 includes an RFID antenna (not shown) which becomes registered or aligned with the identification tag 204 when the grinding wheel 36 is in the illustrated home position, so that the tag 204 may be read from and written to using RFID communications. Generally the RFID antenna has one or more loops of conductive material such as wire or metal etch, with the loops having a circular or other shape (e.g., rectangular). The RFID communications may operate on any of a number of frequencies. Frequencies in common use include 133 kHz (Low Frequency or LF), 13.56 MHz (High Frequency or HF), and 900 MHz (Ultra High Frequency or UHF).
In the illustrated embodiment the identification tag 204 is within the circumference of the circular RFID antenna of the sensor module 222, e.g., concentric with the antenna, during the reading and writing of data from/to the tag 204 as part of operation. By this arrangement the identification tag 204 can be read from and written to even when the grinding wheel 36 is rotating at full speed, which may be between 1000 and 25000 RPM. In some configurations, the tag 204 can be read from and written to when rotating at speeds between 700 RPM and 5000 RPM. In some configurations, the tag 204 can be read from and written to when rotating at speeds between 1000 RPM and 4000 RPM. Reading and writing at full rotational speed has a distinct advantage of allowing the sharpener 10 to sharpen more quickly, because it is not necessary to slow/stop wheel rotation and then bring rotation back up to speed for each read/write operation. As described more below, in one embodiment reading and writing occurs once during each 2-pass cycle, so the time savings is proportional to the number of cycles in a sharpening operation. Additionally, reading and writing at full rotational speed can discourage any tampering with the grinding wheel 36, because it is always moving during any attempted authentication or reading/writing process. In some embodiments it may be advantageous to maintain rotation but at a reduced rotational speed to improve the read/write communications with the tag 204.
As the adjustment member 244 is turned, it presents different faces of the scalloped lower edge at a rest position of the limit peg 248. When the grinding wheel 36 is clear of the skate blade and the motor arm 78 rotates upward under the action of the spring 84, the upward travel is limited by the limit peg 248 encountering a face of the lower edge of the adjustment member 244. The different faces of the adjustment member 244 are at different radii from the center of rotation of the adjustment member 244, thereby establishing different vertical locations for this rest position of the limit peg 248.
In operation, a user rotates the adjustment member 244 to set a maximum vertical position of the grinding wheel 36. The purpose of this adjustment is to set a vertical travel limit of the grinding wheel 36 when it comes off the edge of the skate blade. This feature helps tailor operation depending on the type of skate being sharpened. Regular ice hockey skates have rounded upturns at each end of the skate blade (e.g. toe or heel), and it is desired that the grinding wheel 36 move upward to follow the upturns. This can be accomplished by having a high maximum vertical position. The blades on so-called “goalie skates” are flatter and it is typically desired that the grinding wheel 36 not move as far upward as it leaves the end of the blade, but rather come off relatively straight. This can be accomplished by adjusting the height limit using the adjustment member 244 to set a lower maximum vertical position.
In
One feature visible in
Another pertinent feature relates to a Y-adjustment mechanism permitting fine adjustment of the position of the grinding wheel 36 to align it with a retained skate blade in the X-Z plane (which is perpendicular to the page of
The grinding wheel 36 utilizes the identification tag 204 to carry important information and provide it to the control unit 32 of the sharpener 10. The information carried by the tag 204 can be used to improve sharpening operation and reduce costs associated with the skate sharpener 10.
Accurate and repeatable skate sharpening is obtained when the grinding wheel 36 is in good condition (e.g. running true, not excessively worn, not damaged). One of the limitations of existing sharpeners is that there is no indicator for the user that alerts them when the grinding wheel is not in good condition. Generally the user must make a judgment call on when to retire a grinding wheel. This may occur, for example, in response to a bad skating experience with skates that were sharpened with a grinding wheel that is no longer in good condition.
The disclosed sharpener 10 can use the data-carrying ability of the grinding wheel 36 to track usage, and employ the usage information in some way to promote delivery of consistent high quality sharpening. Generally this will involve comparing actual usage to a usage limit that has been predetermined as a dividing point between high quality sharpening and unacceptably low quality sharpening. When the usage limit is reached, some action is taken. For example, the control unit 32 may provide an indication to a user via the user interface display panel 34. It may also reduce or eliminate the likelihood of further use of the grinding wheel 36, i.e., refrain from performing any passes with a wheel whose usage has reached the limit, even if such continued use has been requested by a user.
In one embodiment, the above usage tracking may be realized by initially loading the usage limit value onto the tag 204 and then subtracting or “debiting” the stored value as the grinding wheel 36 is used. The usage limit may be deemed to have been reached when the stored value reaches a predefined number such as zero. Generally the usage tracking and usage limit may be specified in any of a variety of ways, including a count of passes or cycles as has been mentioned, or alternatively by counting operating time (tracking the operating time for each sharpening and accumulating the time values over a period of successive sharpenings). If the usage limit value is specified as a maximum number of passes, then the value is decremented by two for each 2-pass cycle of the grinding wheel 36 over a skate blade during sharpening. In one embodiment, this decrementing can take place once each cycle, with the grinding wheel 36 passing through the home position (
A specific example is now provided for illustration. It is assumed that the useful lifetime of a grinding wheel 36 is on the order of 160 passes. This translates to approximately 10 sessions of sharpening a pair of skates if an average of 4 cycles (8 passes) is used per skate (8*2*10=160).
In a given embodiment, usage may be tracked in units of passes, cycles, blades sharpened (assuming some fixed or limited number of passes per blade), time, or some other scheme. The UI display 34 may be used to display remaining usable life for a grinding wheel 36 to the user.
For example, it may be displayed as a fraction or percentage, or as more general ranges which could be indicated by colored indicators, for example—e.g., green for high remaining lifetime, white or other neutral color for intermediate, and red for low remaining lifetime. In one embodiment a linear array of indicators may be used, and indicators successively extinguished from one end as usage increases, and the end-of-life indicated by no indicators being lit.
Since there will be user-to-user variability in how many passes are done for a skate sharpening, the system may alert a user when the number of cycles needed to complete a sharpening exceed the number of cycles of remaining life of the grinding wheel 36. The alert may be provided, for example, by dimming or flashing a set of indicators, and/or by stopping a sharpening that is in progress or reducing or eliminating the likelihood of a new sharpening from beginning. Generally, it is desired that the display technique enable a user to accurately plan for use and avoid running out of usable grinding wheel lifetime in the middle of a sharpening
Beyond the usage tracking information, the tag 204 may also be used to carry system setup parameters that the control unit 32 can read and then apply to operation. This programming-type approach can enable a single sharpener 10 having a generalized design to be used in a wide variety of ways. For example, the tag 204 may contain parameters for the rotational speed of the grinding wheel motor 80; the speed of translation of the carriage assembly 70 across the skate blade; and the magnitude of a normal grinding force (i.e., the force applied by the grinding wheel 36 in a direction normal to the bottom face of the skate blade 40). Employing customizable settings in this manner can support variability in the materials, diameters, and grits used for different grinding wheels 36. Larger wheel diameters for different skates, or different grits for different skate steels or surface finishes, will generally require different system settings (grinding wheel RPM and translation speed) for optimized use. In operation, the control unit 32 can read the parameters from the tag 204 and then apply the parameters prior to beginning a sharpening operation, such as by programming the appropriate controllers 132 (
The identification tag 204 may also store user-specific settings to be used for sharpening operations, such as a default number of passes for a skate sharpening. The control unit 32 can read such values and then use them unless they are overridden by a specific current selection by the user. One user may sharpen relatively frequently and typically use a small number of passes, such as two, while another user may sharpen less frequently and typically use a larger number of passes, such as eight. The user interface preferably would enable a user to modify or update any such persistently stored values. Saving user-specific values on the grinding wheel 36 also enhances “portability” of the customization. A user can carry their own grinding wheel 36 and mount it for use in different sharpener systems 10 at different locations while still obtaining the same user-specific operation. For example, an organization such as a hockey club or rink operator can provide access to a sharpener system 10 and allow users to swap grinding wheels 36, so that each user receives a desired user-specific experience.
The sharpener system 10 may also have features for defeating counterfeiting or certain tampering with tags 204. For example, it might record the unique tag identifiers (e.g., tag serial numbers) for every tag 204 that has been used over some interval on that sharpener, as well as recording the number of passes that were last seen on the tag 204. If there is ever a time when a sharpener 10 sees a grinding wheel 36 that it has seen before but having remaining pass count greater than the number of remaining passes last seen on that wheel, the sharpener 10 could deem the grinding wheel 36 to be a counterfeit or tampered with and prevent its use. This might be done to insure that only grinding wheels 36 of sufficient quality are used, to obtain good sharpening results and avoid any unsafe conditions that could occur by using a defective or inferior grinding wheel 36. The system 10 may store the most recent passes remaining count as individual numbers or as percentages similar to the way the system displays the grinding wheel remaining life to the user.
Yet another possibility is for the tag 204 to store system fault data, i.e., data describing fault conditions that have occurred during a sharpening operation. This can help users interact with technical service to diagnose problems they may be having with their machine. A manufacturer or service organization might request that the user send a grinding wheel 36 to that organization for review. The grinding wheel is smaller and thus far cheaper and convenient to send than is the entire system 10. At the manufacturer or service organization, technicians can read fault data such as fault codes from the wheel 36. In another embodiment, the identification tag 204 may be compatible with readers such as near-field communications (NFC) readers such as used on smart phones and similar small computing devices. When the user experiences a system fault, the user can remove the grinding wheel 36 and place it near the computing device. The device might immediately launch an application or navigate to a particular web site to provide information to the user about the particular fault that is identified by the fault data stored on the tag 204. Another use for this type of interface is for repurchasing grinding wheels 36. The application or website launched by the device may provide product ordering functionality, enabling a user to easily obtain replacement grinding wheels 36 as existing grinding wheels are used up. In some configurations, the application or website, for example, may provide a tool for reading a grinding wheel life indicator and, in some configurations, for providing the ability to reorder grinding wheels. Such configurations can simplify the ordering process for operations or individuals with a large number of rings to track, monitor and replace, for example but without limitation.
At 272, the system 10 tracks usage of the grinding wheel 36 for sharpening operations and writes updated usage tracking values to the usage location as the grinding wheel 36 is used for the sharpening operations. Usage may be tracked by counting passes, for example, in which case it may be convenient for the usage tracking value to be expressed as a pass count. The usage value may directly indicate an amount of usage that has occurred, e.g., as an increasing count of passes, or it may be directly indicate an amount of usage remaining, e.g., as a decreasing count of passes.
At 274, the system 10 reads a current usage tracking value from the usage location and selectively enables and disables sharpening depending on whether a usage limit has been reached, as indicated by a relationship between the current usage tracking value and a predetermined usage limit value. When a decreasing or decremented usage value is used to indicate an amount of usage remaining, then the predetermined usage limit value can be used as the starting usage value, and the usage limit is reached when the usage value is decremented to zero. As indicated above, the system 10 also can read usage parameters (e.g., rotational speed, translation speed, etc.) for use during operation. Furthermore, one or more of those usage parameters may vary over the life of the grinding wheel such that, as the grinding wheel experiences wear over time, the operation of the system may be adjusted accordingly.
Referring first to the slot cover 28, a button 27 is mounted for rocking on a horizontal axis and has a downward-extending rack 300 at the rear. The rack 300 engages a pawl 302 attached to the arch (rounded projections) 64. A spring (not shown) biases the button 27 so that its top is co-planar with the top of the slot cover 28 and the rack 300 engages the pawl 302, locking the slot cover 28 in place. In use, a user depresses a front part of the button 27 (see
Referring next to the blade clamping mechanism, as shown in
When the clamp paddle 26 is in the position shown, the cam 96 presents a lower-radius face to the piston 306, and the spring 310 urges the pull rod 102 to a maximum retracted position, to the left in
A user opens the clamp jaws 90 by pushing downward on an outer part of the paddle 26, rotating it counterclockwise in the view of
As shown in
The above motion reverses when the jaws 90 are opened. As the rear jaw 90-R is pushed in the X direction, clamping tension is released and it slides downward in the Z direction, closing the space 347 and returning to the position of
In the illustrated embodiment as described above with reference to
In the illustrated embodiment the jaws 90 are urged against a lower or bottom surface of the spacer blocks 343, which are fixedly secured to the underside of the platform 22 of the chassis 14. More generally the jaws 90 are urged against a surface that is in some manner referenced to the chassis 14, i.e., having a fixed position with respect to the chassis 14. In an alternative embodiment, the jaws 90 might be secured directly to a surface of the chassis 14 itself, such as the bottom surface.
With reference now to
With the illustrated clamping mechanism 1088, the pull rod 1102 is urged to the left in
In the illustrated configuration, the paddle 1026 is removable from the cam member 1096. In some configurations, the paddle 1026 is designed to slide off of the cam member 1096 in a vertical direction. Thus, in such advantageous configurations, the paddle 1026 would be prone to separate from the cam member 1096 if a user were to attempt to lift the skate sharpener 1010 using the paddle 1026. By allowing the paddle 1026 to separate in this manner, a risk of damage to the clamping mechanism 1088 caused by lifting from the paddle 1026 can be reduced or eliminated. In the illustrated configuration, as shown in
With reference now to
As shown in
In addition, to provide fine adjustment of the jaws 1090F, 1090R during manufacture, the jaws 1090R, 1090R are secured in position relative to the spacer blocks 1343F, 1343R using fasteners 1338. These fasteners 1338 can be secured to the spacer blocks 1343F, 1343R. In some configurations, as shown in
In some configurations, one or both of the jaws 1090F, 1090R can be provided with one or more additional motion confining element. In the configuration illustrated in
With reference to
As shown in
The illustrated jaw risers 1364 have a contoured upper surface 1366. The contoured upper surface 1366 can include one or more indicators to help guide a user for placement of a finger or thumb during installation and/or removal. Moreover, the contoured surface provides a region of reduced cross-section that allows increased flexure in the region of the indicators.
In the illustrated configuration, pins 1368 are disposed directly below one or more of the contoured regions 1366. The pins 1368 are received within the openings 1362 formed on the land portions 1360 of the jaws 1090F, 1090R. The pins 1368 can help guide the user to correct installation. The pins 1368 also can reduce or eliminate the likelihood of the jaw risers 1364 sliding laterally off of the land portions 1360 when installed correctly.
The jaw risers 1364 also include hooked ends 1370. The hooked ends 1370 enable the jaw risers 1364 to be secured to the jaws 1090F, 1090R. In some configurations, the hooked ends 1370 can be designed and configured to snap-fit to the land portions 1360 of the jaws 1090F, 1090R. Other configurations also are possible.
With reference to
The illustrated jaw guard 1380 is secured to the rear jaw 1090R. In some configurations, the jaw guard 1380, when positioned within the skate sharpener 1010, has an uppermost contact portion 1382 that is vertically higher than a rotational axis of the grinding wheel (i.e., which is coaxial with the spindle 1082 in the illustrated configuration) in its uppermost position and a lowermost contact portion 1384 that is vertically lower than a lowermost portion of the jaws 1090F, 1090R. Preferably, the lowermost contact portion 1384 is a distance below the jaws 1090F, 1090R that is sufficient to ensure that the grinding wheel 1036 does not contact the bottom of the jaws 1090F, 1090R. In this manner, the grinding wheel will be forced downward a sufficient distance to clear the bottom of the jaws 1090F, 1090R.
With reference now to
In the illustrated embodiment, the bumper 29 is attached to the body of the slot cover 28 (at lower left corner in
In operation, the limit switch 328 is electrically open by default. In addition, the actuation lever 326 is held away from actuating the limit switch 328 by the mechanical biasing action of the spring 330. When the face portion 322 of the bumper 29 is depressed (e.g., brought into contact with a skate blade or skate blade holder), the bumper 29 rotates (clockwise in this view) and the arm 324 depresses the limit switch lever 326, causing the limit switch 328 to change from electrically open to electrically closed. If the cover moves even further into engagement with the skate or skate blade holder, the over-travel would be taken up by bending of the leg 324 that engages the switch 328.
When the face portion 322 of the bumper 29 is no longer depressed (e.g., the skate blade or skate blade holder is removed or the cover 28 is moved away from the skate blade or skate blade holder), the spring 330 acts to return the bumper 29 to the original position and the arm 324 stops depressing the limit switch lever 326, which returns the limit switch 328 to the normally electrically open state.
The state of the limit switch 328 as open or closed is sensed by the controller 32. In one embodiment, sharpening operation is permitted only when the limit switch 328 is sensed as electrically closed, which normally occurs when a skate blade is clamped in position and the slot covers 28 have been moved inward to contact the skate blade holder. In these operating positions the slot covers 28 cover the outer ends of the slot 24 that would otherwise be open. The operating position of the slot cover 28 can also be referred to as an occluding position. In the operating position, the position of the slot covers 28 can reduce, limit, or eliminates the likelihood of the introduction of any objects through the outer ends of the slot 24, where such objects might harmfully contact the rotating grinding wheel 36 as it moves along the slot 24, during a sharpening operation. If the limit switch 328 of either slot cover 28 is sensed as open, which normally occurs when either a skate or skate blade holder is not present or both slot covers 28 have not been moved inward to their operating positions, the controller 32 prevents sharpening operations, i.e., provides no electrical drive to the grinding wheel motor 80 and the carriage motor 260. With these motors not rotating, it is safer to introduce objects (such as a skate blade during mounting, for example) into the slot 24. By using the configuration described, a failure of the switch or of the switch actuating mechanism would result in the controller 32 detecting that the skate sharpener 10 is not reading to sharpen.
With reference to
The lighting feature 332 can be always on when the slot cover 28 is not in contact with a skate blade or a skate blade holder. In other words, the lighting feature 332 can direct the user's attention to the need to close the slot cover 28 prior to initiating operation of the skate sharpener 10. When the slot cover 28 has been moved into engagement with the skate blade or skate blade holder, the lighting feature 332 is turned off. If a user attempts to start a skate sharpening operation without closing the slot covers 28, the lighting feature 332 will flash to direct the user's attention to the need to close the slot covers 28 and, as discussed directly above, the controller will not initiate the skate sharpening operation until the slot covers are moved into position in engagement with the skate blade or skate blade holder. In some configurations, the lighting feature 332 is turned off, or an intermittent flashing is started or stopped, when the slot cover 28 has been moved into engagement with the skate blade or skate blade holder. Any other suitable attention directing configurations can be used.
There are various alternatives to the configuration described above. An alternative to the bumper 29 may be a piston-like mechanism that moves linearly to actuate a switch, instead of rotating about a fixed pivot point as in the above. It is not necessary to use a limit switch with an actuation lever; in an alternative arrangement, the bumper 29 (or analogous member) may directly push on the button of a limit switch. Also, in some embodiments, a separate spring 330 may not be required. It may be possible to rely on the spring of a limit switch to provide a bias or return force. However, it may be desirable to use a separate spring to provide for adjustment of either/both the range of motion and actuation force of the bumper. In yet another alternative, a contactless switch such as an optical emitter-detector pair could be used, with the skate or skate blade holder breaking the optical path to trigger the switch.
In the illustrated embodiment the slot covers 28 are affixed and always present, but in an alternative embodiment they could be separate components that are placed and locked onto the ends of the skate or skate blade holder by the user prior to sharpening. Also, while in the illustrated embodiment the slot covers 28 move by sliding, they could alternatively move by rotating on a hinge, telescoping, or rolling out (like a breadbox or garage door).
As mentioned above, slot cover designs that differ from those shown in
The slot cover 1028 has a body 1313 that can be connected to the front platform portion 22 of the skate sharpener. Disposed along one side of the body 1313 is an opening 1314 sized and configured to receive at least a portion of a skate blade or a skate blade holder (not shown). The opening 1314 preferably extend to the lowermost portion of the body 1313 such that a full doorway is defined by the opening 1314.
The opening 314 is generally closed by a door or bumper 1322. The bumper 1322 is sized and configured to contact the skate blade or skate blade holder. The bumper 1322 in this configuration is designed to pivot about a generally horizontal axis (i.e., different from the generally vertical axis of the bumper 322 shown in
The bumper 1322 has a leg 1324 that is connected to the bumper 1322 such that rotation of the bumper 1322 causes rotation of the leg 1324. Rotation of the leg 1324 brings the leg 1324 into and out of engagement with a switch 1328. In some configurations, the switch is configured to an electrically open state when the bumper 1322 is not depressed. For example, the switch 1328 can be mechanically pushed shut without a skate present but the switch 1328 is electrically open in this state. When brought into contact with a skate blade or skate blade holder, for example, the switch 1328 can be relieved or mechanically released and the switch 1328 can transition to an electrically closed state, thereby indicating the presence of the skate. In some configurations, the leg 1324 is in engagement with a lever or contact location 1326 of the switch 1328 until the bumper 1322 contacts a skate blade, skate holder or the like, which causes the leg 1324 to rotate away from the switch 1328. The rotation of the leg 1324 away from the switch 1328 causes the switch 1328 to go to an electrically closed state. This configuration enables the switch 1328 to close the circuit when the bumper 1322 is depressed or otherwise in contact with a skate blade, skate blade holder or the like. The switch can be configured such that a very short travel distance of the leg 1324 is all that is needed to open or close the electrical circuit.
The leg 1324, the bumper 1322 or both can be biased into the closed position. In some configurations, a biasing member biases the bumper 1322 into a closed position, which results in the leg 1324 being also biased into the closed position. In the some configurations, the biasing member 1330 is a torsion spring. In the illustrated configuration, two torsion springs are provided such that the bumper 1322 can be loaded on each lateral side equally. The force provided by the biasing member(s) 1330 can be selected to provide sufficient force on the switch 1328 to maintain the switch in the closed position unless the bumper 1322 is brought into contact with a skate blade, a skate blade holder or the like. Other biasing members or mechanisms also can be used.
As shown in
With reference again to
With continued reference to
As shown in
The body 1313 also was provided with guards 1316. The guards 1316 extend laterally outward from the body 1313. In the illustrated configuration, the guards 1316 extend laterally outward in regions generally adjacent to the opening that receives the door 1322. In the illustrated configuration, the guards 1316 are positioned vertically lower than the bottom surface of the body 1313. The guards 1316 extend vertically downward below the bottom surface of the body 1313 but not so far as to contact the jaws or another component that may be positioned within the slot of the skate sharpener 10. As shown in
With reference now to
The slot cover 2028 has a body 2313 formed of two main parts, a base 2309 and a cover 2311. In the illustrated configuration, the base 2309 houses and comprises most of the operational features of the slot cover 2028 while the cover 2311 provides more of a cosmetic skin for the slot cover 2028. The cover 2311 protects the internal components contained within the base 2309. In some configurations, the cover 2311 can be snap-fit or press-fit with the base 2309. In some configurations, the cover 2311 and the base 2309 can be secured with mechanical fasteners. In some configurations, the cover 2311 and the base 2309 can be snap-fit together and secured with a threaded fastener 2303 (see
With reference to
The body 2313 also comprises an edge recess 2319. The edge recess 2319 is positioned along the side of the body 2313 that will face the skate during use. The edge recess 2319 lowers the height of the body 2313 in a region that will be adjacent to the skate during a sharpening operation. By reducing the height of the body 2313 in this region, a greater variety of skate designs can be accommodated. In some configurations, the edge recess 2319 and the recess 2317 can be connected to define a single recess. In some configurations, the recess 2319 and the recess 2317 can be eliminated by lowering the upper surface and replacing the recess 2317 with a protrusion or the like to guide a user to move the cover 2028.
With reference now to
The door 2322 has a leg 2324 that is connected to the door 2322 such that rotation of the door 2322 causes rotation of the leg 2324. Rotation of the leg 2324 brings the leg 2324 into and out of engagement with a switch 2328. In some configurations, the switch is configured to be normally closed and in an electrically open state. In such configurations, the leg 2324 is in engagement with a lever or contact location (not shown) of the switch 2328 until the door 2322 contacts a skate blade, skate holder or the like, which causes the leg 2324 to rotate away from the switch 2328. Because the switch 2328 is normally closed, the rotation of the leg 2324 away from the switch 2328 causes the switch 2328 to go to an electrically closed state. This configuration enables the switch 2328 to open the circuit when the bumper 2322 is no longer in contact with a skate blade, skate blade holder or the like. The switch can be configured such that a very short travel distance of the leg 2324 is all that is needed to close the electrical circuit.
The leg 2324, the door 2322 or both can be biased into the closed position. In some configurations, a biasing member biases the door 2322 into a closed position, which results in the leg 2324 being also biased into the closed position. In the some configurations, the biasing member 2330 is a torsion spring. The force provided by the biasing member 2330 can be selected to provide sufficient force on the switch 2328 to maintain the switch in the closed position unless the door 2322 is brought into contact with a skate blade, a skate blade holder or the like. Other biasing members or mechanisms also can be used.
In the configuration shown in
As with the cover 1028 described directly above, the cover 2028 includes a lighting feature 2332. The lighting feature 2332 in the illustrated in the illustrated configuration is on an upper or top surface of the cover 2311. As shown in
With reference to
In addition, as shown in
The body 2313 also was provided with guards 2316. The guards 2316 extend laterally outward from the body 2313. In the illustrated configuration, the guards 2316 extend laterally outward in regions generally adjacent to the opening that receives the door 2322. In the illustrated configuration, the guards 2316 are extend to a location vertically lower than the bottom surface of the body 2313. The guards 2316 extend vertically downward below the bottom surface of the body 2313 but not so far as to contact the jaws or another component that may be positioned within the slot of the skate sharpener 10. As shown in
The printed circuit board of the cover 2028 can be connected to the controller of the skate sharpener in any suitable manner. In one configuration, an FFC cable can be used to connect the printed circuit board and the controller of the skate sharpener. Advantageously, the FFC cable can be concealed within the front platform portion 1022 (see FFC in
With reference now to
The youth skate adaptor 2336 effectively extends the reach of the door 2322 toward the skate blade or skate blade holder. In some configurations, the adaptor 2336 can be positioned between the guards 2316. In the illustrated configuration, the adaptor 2336 can snap fit to the door 2322. The adaptor 2336 can have a ribbed, stepped or textured surface 2337 on a projecting portion 2338. In some configurations, both the top and the bottom of the projecting portion 2338 can include the textured surfaces 2337.
As shown in
With reference now to
The front portion 1022 and the rear portion 1021 can be formed in any suitable manner. In one configuration, each of the front portion 1022 and the rear portion 1021 can be separately extruded. In one configuration, the front portion 1022 includes a recess 1019. The rear portion 1021 includes a portion that is received within the recess 1019 of the front portion 1022. The rear portion 1021 can be secured to the front portion 1022 using any suitable technique. In some configurations, mechanical fasteners can be used to secure the rear portion 1021 to the front portion 1022. In some configurations, one or more threaded fasteners can be used to secure the front portion 1022 and the rear portion 1021 together (e.g., see the holes shown in the recess 1019 in
The rear portion 1021 includes the rails 1060. In the illustrated configuration, the rails 1060 are supported by a web that connects the rails 1060 to the main body of the rear portion 1021. In such a manner, the rails 1060 and the main body of the rear portion 1021 can be formed as a single extrusion, which improves manufacturability and decreases assembly time. In some configurations, however, the rails 1060 can be formed separate of the main body and secured thereto using any suitable technique. For example, the rails 1060 can be secured to the main body using mechanical fasteners, such as threaded fasteners, or the like.
The rails 1060 support the carriage assembly 1070. As described above, the rails 1060 generally extend in the X direction and the carriage assembly 1070 is configured to translate along the rails 1060. While the configuration of the carriage assembly 70 shown in
As illustrated best in
Over time, wear can occur between the carriage assembly 1070 and the rails 1060. Accordingly, a method and/or assembly to accommodate the wear and increase the life of the assembly would be desirable. One such method and/or assembly can include providing the interface between the carriage assembly 1070 and the rails 1060 with wear members. In the illustrated configuration, the carriage assembly 1070 comprises guide channels 1075. The guide channels 1075 extend along at least a portion of the length of the carriage 1072. In the illustrated configuration, the guide channels 1075 extend along the full length of the carriage 1072. The guide channels receive the rails 1060. To reduce wear of the guide channels 1076, one or more bushing liner 1076 can be provided. In the illustrated configuration, two bushing liners 1076 are positioned along each of the guide channels 1075. The bushing liners 1076 can be spaced apart along the length of the guide channel 1075. Other configurations are possible.
With reference to
While bushing liners 1076 can help improve the movement of the carriage 1072 along the rails 1060, wear over time can affect the consistency of movement. Thus, one or more of the illustrated bushing liners 1076 are biased into abutment with the rails 1060. In the illustrated configuration, two bushing liners 1076 that engage a single rail 1060 are biased into abutment with that rail 1060. With reference to
A biasing member 1081 can be captured between the floating bushing 1077 and a threaded member 1085. The threaded member and/or the floating bushing 1077 can include a recess that receives the biasing member 1081. In the illustrated configuration, the floating bushing 1077 includes a recess that surrounds a post member and at least a portion of the biasing member 1081 is received within the recess and supported by the post member. The biasing member 1081 urges the floating bushing 1077 into engagement with the bushing liner 1076. Other configurations are possible. Advantageously, by incorporating a pre-loaded bushing and/or pre-loaded bushing liner, it is possible to maintain a relatively consistent low-level friction component between the carriage assembly 1070 and the rails 1060 for a relatively long period of time during which wear will be occurring. As such, improved performance results from the use of the pre-loaded bushing and/or bushing liner.
The pivot spindle 240 is secured at each end to the carriage 72. A pivot section 400 of the motor arm 78 is mounted on the pivot spindle 240 by a combination of bearings 402, 404 and bushings 406, 408. Shown on the right in this view is a spring 410 disposed in compression between the front wall of the carriage 72 and an inner race 412 of the bearing 404. Shown on the left is the spindle gear 253 which is disposed on a hub or nut 414 having screw threading engaging corresponding screw threading on the pivot spindle 240. It will be appreciated that the gear and threading features may be integrated into a single component as an alternative. Arranged between the nut 414 and an inner race 416 of the bearing 402 is a washer 418 and a collar portion 420 of the bushing 406, including a detent mechanism as described below.
The mounting of the motor arm 78 on the bearings 402, 404 permits the motor arm 78 to pivot about the pivot spindle 240 so that the grinding wheel 36 can follow the profile of the bottom face of the skate blade during sharpening (as described above with reference to
The transverse or Y-direction (left to right in
The nut 414 and washer 418 are co-configured to form a detent mechanism providing several detent locations for a rotation of the nut 414, helping reduce or eliminate the likelihood of undesired transverse movement of the motor arm 78 after an alignment operation has been performed and a sharpening operation has begun. Specifically, the front face (rightward in
In some configurations, one or more lighting feature can be incorporated into the jaw guard 1380. In some configurations, the lighting feature can be positioned adjacent to the jaw guard 1380. In some configurations, an LED or the like can be mounted in the jaw guard 1380. For example, one or more holes 1381 (see
The LED can be illuminated when the grinding wheel is being aligned. For example, in configurations having an alignment mode, the lighting feature in, on or around the jaw guard can be activated when the skate sharpening device enters into the alignment mode or at some time period during the alignment mode. The lighting feature thereby can illuminate the area surrounding the alignment features.
It will be appreciated that the grinding wheel 36 can be moved transversely (up and down in the view of
In use, a user opens the jaws 90 and inserts the alignment tool 440, locating it so that the shoulder portions 450 sit on top of the endward clamping portions 436 of the jaws 90 and the protrusions 452 are received by the notches 438. The user then closes the jaws 90 so that the alignment tool 440 is retained with the blade-like portion 442 in the same position as a skate blade 40 is retained during sharpening. The carriage 70 is then moved to bring the grinding wheel 36 to the position shown in
In one embodiment the movement of the grinding wheel 36 into the alignment position of
In some configurations, the motor 260 can be a stepper motor 1260. In such configurations, it is possible to specifically define a calibration position. The stepper motor can cause movement of the grinding wheel to the location desired for the alignment operation. For example, the number of steps can be counted and the calibration positon can be determined based upon the number of steps. Moreover, the number of steps to a grinding wheel change location can be counted. As such, movement of the carriage to a location that allows for interchanging of grinding wheels can be provided with consistency and repeatability.
With reference to
The belt grabber 1066 can include a channel 1267 that receives a belt 1268 and secures the belt grabber 1066 in position along the belt 1268. In some configurations, a bend or the like is disposed along the channel 1267. In some configurations, the channel 1267 is generally V-shaped. In some configurations, the channel 1267 includes one or more teeth along the length of the channel. In some configurations, one wall that defines the channel 1267 includes a plurality of teeth. In some configurations, the belt 1268 includes teeth and the channel 1267 includes teeth that mesh with the teeth of the belt 1268. Other interlocking or coupling structures also can be used to join the belt 1268 to the carriage assembly 1070.
As indicated,
The process further includes at 462 operating an adjustment mechanism while visually observing the area where the visual reference features are located to bring them into alignment with each other. This brings the grinding wheel and the retained skate blade into an aligned position in which the centerline of the grinding wheel is aligned with the centerline of the retained skate blade. In one embodiment the adjustment mechanism may be configured and used such as described above, but the adjustment mechanism may be realized in different ways in alternative embodiments.
Referring again to
Because the flag 448 has a height much greater than its thickness, if a user were viewing from a slightly incorrect angle then the flag 448 would appear thicker than when viewed from directly above. A user can adjust his/her viewing angle until the thickness is minimized. Alternatively, if light is striking the sides of the flag 448 then the illuminated sides will be slightly visible when the flag 448 is viewed off-angle. The notch 454 also provides for parallax detection, because it will only be visible as a notch when viewed from directly above. When the area of the notch 454 is viewed off-angle, the notch is visually filled by its own inside surface.
It is noted that the placement of the notch 454 toward an edge of the grinding wheel 36 has significance. Proper grinding occurs at the center of the grinding wheel 36, so if the alignment mark were placed at the center of the grinding wheel 36 then it would be affected by grinding and potentially lose its ability to function as an alignment mark. It might even be erased completely before the end of the usable lifetime of the grinding wheel 36. When formed as a notch or similar feature, it might also compromise the quality of the sharpening. By placing the alignment mark in the form of the notch 454 nearer the edge or face of the grinding wheel 36 it is not affected by the normal wearing of the abrasive over a period of use, and it does not interfere with grinding.
With reference now to
With reference to
The grinding ring 3002 preferably comprises an exposed inner surface 3003. In other words, this inner surface 3003 is not covered by any portion of the hub 3004. In some configurations, the edge between a radially extending surface 3001 and the axially extending inner surface 3003 is chamfered. The chamfered corner assists with mounting of the grinding wheel 3002 onto the receiving portion of the skate sharpening system.
In some configurations, the inner surface 3003 has a diameter of between 25 mm and 100 mm. In some configurations, the inner surface 3003 has a diameter of 37 mm. In some configurations, the inner surface 3003 has an axial length of between 1 mm and 5 mm. In some configurations, the axial length of the inner surface 3003 is at least 2.0 mm. In some configurations, the axial length of the inner surface 3003 is 2.3 mm In other words, a distance of at least 2 mm is provided between the radial surface 3001 and any other component such that a mounting clearance is defined. Such configurations advantageously result in an axial gap being initially formed between the hub 3004 and the end surface of the arbor (see
The grinding ring 3002 comprises an inner groove 3008. The inner groove 3008 is formed on an inner surface of the grinding ring 3002. At least one face of the inner groove 3008 defines a catch surface. The catch surface, as will be described, interfaces with the hub 3004 to lock the grinding ring 3002 to the hub 3004. To simplify manufacture, the groove 3008 preferably is centered between axial ends of the grinding ring 3002.
With continued reference to
With reference to
As also shown in
With reference again to
With reference to
With reference to
Because the communication component 3034 works by receiving energy from the sensor module 1222, the communications component 3034 preferably is spaced apart from the metal of the grinding ring 3002 to improve performance. In other words, as shown in the sectioned view of
In some configurations, when the grinding wheel 3000 is mounted to the skate sharpener 1010, the location of the communications component 3034 is axially offset between 10 mm and 40 mm from the RFID antenna component within the sensor module 1222. In some configurations, the RFID antenna component and the communications component 3034 are axially offset between 15 mm and 25 mm. In some configurations, the axial offset is 20 mm. Such a configuration and such spacings have been found to position the communications component 3034 close enough to the RFID antenna of the sensor module 1222 to power the communications component 3034 yet distance the communications component 3034 from the grinding ring 3002 sufficiently to reduce the interference and energy absorption caused by the grinding ring 3002. Thus, in the illustrated configuration, there is an axial offset in location between an axially outermost portion of the grinding ring 3002 and the axial location of the communications component 3034. Moreover, the communications component 3034 is mounted to a non-metallic component (e.g., the hub 3004.
When manufacturing the grinding wheel 36, certain processing steps are used specifically to form the notch 454. Such steps are not required in manufacturing the grinding wheel 500. Moreover, the additional grinding wheel width that provides sufficient footprint to accommodate the notch 454 is less desired from a true-spin perspective. Thus, in some configurations, providing a grinding wheel that does not include the notch 454 may be desirable. However, the alignment between the grinding wheel and the skate blade still is desired. As described below, a separate alignment wheel is used for the alignment process.
The alignment wheel 502 has precise similarity to the grinding wheel 500 so that it occupies the same wheel-mounting location against the arbor 212 as occupied by the wheel 36 as described above. As shown, the alignment wheel 502 includes an alignment notch 504 toward its outer face, similar to the notch 454 on grinding wheel 36. The notch 504 serves as a visual reference feature in the same manner as described above for the notch 454. In this embodiment as described more below, an alignment process results in aligning the wheel-mounting location with the skate blade through use of the alignment wheel 502. The alignment wheel 502 is then replaced with the grinding wheel 500 which is then inherently aligned with the skate blade because it occupies the aligned wheel-mounting location. When the alignment wheel 502 has been aligned and then replaced with the grinding wheel 500, the centerline of the grinding wheel 500 is precisely aligned with the centerline 432 of the jaws 90, just as described above with reference to
In some embodiments, the alignment wheel is a noncircular shape. For example, the alignment wheel can be oblong, square, octagonal, or another geometric shape. In some embodiments the alignment wheel can be asymmetric, where the alignment wheel is not symmetric about an axis.
In some embodiments, the motor arm may be configured to incorporate the second visual reference feature. The position of the second visual reference feature on the motor arm can be positioned such that the motor arm can be moved to an aligned position without using a separate alignment component (such as an alignment wheel). In some embodiments, the second visual reference feature can be incorporated into the arbor 212. For example, the second visual reference feature can be an alignment notch positioned on the arbor 212. In some embodiments, the second visual reference feature can be positioned on another location of the motor arm.
The process of
The process further includes, at 522, operating the adjustment mechanism to bring the first visual reference feature into alignment with the second visual reference feature, thereby bringing the wheel-mounting location of the spindle to an aligned position in which the centerline of the grinding wheel when occupying the wheel-mounting location is aligned with the centerline of the skate blade position. The alignment may be achieved by visually monitoring relative positions of the visual reference features while operating the adjustment mechanism.
Although the alignment processes and apparatus as described herein contemplate a human user who looks through the magnifying lens 446 and rotates the adjustment knob 242, it will be appreciated that in alternative embodiments a more automated process may be used. For example, some manner of machine vision or other apparatus may be used to monitor relative position between the grinding wheel 36 and alignment tool or between the alignment wheel 502 and the alignment tool, and the adjustment mechanism may be driven by an adjustment motor provided with an electrical adjustment signal. In an embodiment employing automation, a controller can then perform the process of
During any grinding operation, the skate sharpener 1010 will generate dust or debris associated with the metal being removed from the skate blade being sharpened. Desirably, the skate sharpener 1010 can be configured for use in a household environment. For at least this reason, dust containment is desired. More particularly, because the skate sharpener 1010 can have one or more light transmissive or transparent components that allow users or observers to see inside of the skate sharpener, dust containment and management is a consideration.
With reference now to
With reference to
In some configurations, one or more magnetic members 4004 can be positioned within the inner compartment of the skate sharpener 1010. In some configurations, the one or more magnetic members 4004 can be positioned on a lower portion of the inner compartment. In the illustrated configuration, the one or more magnetic members 4004 are positioned on or adjacent to a floor of the inner compartment of the skate sharpener 1010. In some configurations, the one or more magnetic members 4004 is positioned within the swarf zone. In the illustrated configuration, the one or more magnetic members 4004 are positioned on or adjacent to the floor of the inner compartment within the swarf zone 4002. In some configurations, the one or more magnetic members 4004 are positioned at least partially within, and/or at least a portion of the one or more magnetic members 4004 is positioned to within, a region positioned vertically below the cutting tool path 4000. These locations can position the one or more magnetic member 4004 in a location that will reduce the movement of the shavings or grindings and, therefore, provide a cleaner appearance to the skate sharpener. In some configurations, the one or more magnetic member 4004 is a cap that is positioned at or near the swarf that sprays out from the grinding wheel as the grinding wheel sharpens the skate blade. In some configurations, the cap captures between about 65% and 80% of the metal dust generated in a sharpening operation. This capture of the dust helps maintain a tidier appearance and improves operation and life of a dust capture and/or filtration system 4010.
With reference now to
As will be described, in some configurations, the skate sharpener 1010 can be configured to not operate without the dust pan 4012 in positon within the skate sharpener. For this reason, one or more switches 4018 can be provided. The lip 4014 can bear against the switch 4018 such that the presence or absence of the dust pan 4012 can be detected. Other configurations also can be used. In addition, the magnetic member 4004 can be positioned on top of, underneath or within the dust pan 4012.
The illustrated dust pan 4012 includes an upwardly embossed portion 4020. The upwardly embossed portion 4020 overlies an air filter assembly 4022. As illustrated, the air filter assembly 4022 comprises a base 4024 and a capture ring 4026 that secure a filtration element 4028 in position. The filtration element 4028 can be any desirable medium so long as the filtration element 4028 is able to trap and retain dust generated during operation of the skate sharpener 1010. In some configurations, the filtration element 4028 is a HEPA filter element.
As illustrated, the base 4024 includes one or more internal ribs or other structural features 4030 that hold the filtration element 4028 above a floor of the air filter assembly. Thus, the filtration element is positioned above an air flow exit from the illustrated air filter assembly 4022. Of course, other assemblies can be used to filter airflow through an air filter assembly.
The capture ring 4026 overlies the filtration element 4028 and secures the filtration element 4028 in position. In some configurations, the capture ring 4028 is pivotable about a rear portion and includes catches or the like to allow the capture ring 4028 to squeeze on the outer periphery of the filtration element 4028. In some configurations, a ring-like seal or the like can be positioned between the base 4024 and the filtration element 4028 such that air flow must pass through the filtration element 4028 rather than bypassing the filtration element by passing between the base 4024 and the filter element 4028. In some configurations, a sealing relationship or assembly could be established between the capture ring and the filter. Other configurations also are possible.
An exit 4032 is formed in one end of the air filter assembly 4022. The exit 4032 leads upwardly into a blower 4034. The blower 4034 can have any suitable configuration. In the illustrated configuration, the airflow enters that a central opening 4036 (see
Advantageously, the flow generated by the blower 4034 also can draw airflow in though the opposite end of the skate sharpener 1010 to further aid in cooling of the stepper motor 1260, where present. Most of the flow into the air filter assembly 4022 occurs either around the edges of the outer lip 4014 or through a small carveout 4046 (see
As discussed above, operation of the skate sharpener can be interrupted or otherwise controlled based upon various sensed conditions. For example, when the switches of the slot covers indicate to the controller that the slot covers are not in position over the slot and adjacent to the skate blade or skate blade holder, the controller may interrupt power to one or more of the motors that drive the grinding wheel.
Similarly, as discussed above, the switch 4018 can be used to detect the presence or absence of the dust pan 4012. When the dust pan is not present, the controller again may interrupt power to one or more of the motors that drive the grinding wheel. While not shown, a switch can be provided that indicates the presence or absence of the filter element. Again, operation of one or more of the motors that drive the grinding wheel can be interrupted if the filter element is not detected as being present.
Further, as shown in
In some configurations, the controller can be configured to detect the absence or presence of a grinding wheel prior to initiation of a grinding operation. In some embodiments, the controller may determine whether the grinding wheel is present by detecting an identification tag 204 of the grinding wheel. When the grinding wheel is not present, the controller may interrupt power of one or more of the motors that drive the grinding wheel, or otherwise prevent initiation of a grinding operation.
In some configurations, any or all of these operations can be performed by something other than the controller. For example, the switches can, themselves, simply interrupt the power. In use, if any of the slot covers or door are not in the operating position, the skate sharpener will stop grinding or thwart the initiation of a grinding operation. Thus, the skate sharpener can provide improved operating characteristics that result in the user obtaining the full benefit of each of the designed in features.
A soft start routine for operational control of the skate sharpener can be described with additional reference to
In some embodiments, a soft start routine can be implemented to help reduce bouncing when the grinding wheel 36 first contacts the skate blade 142. Before the grinding wheel 36 contacts the skate blade 142, the grinding wheel 36 travels a distance between the home position and the contact position of the skate blade 142. Without a soft start routine enabled, the grinding wheel 36 may rotate at full speed, for example between 4000 rpm and 12000 rpm, and spin at roughly this rate for the complete grinding operation. In embodiments that implement a soft start routine, the grinding motor 80 may initially operate at a lower speed, such as 500 rpm to 3500 rpm until contact is made with the skate blade 142.
The soft start routine can help to reduce bouncing when a grinding wheel first contacts the skate blade. The soft start routine can help to reduce the opposing forces experienced between the grinding wheel 36 and the skate blade 142 at the point of first contact. By reducing grinding wheel RPM at the point of contact, the grinding wheel 36 can experience reduced forces which help to reduce the downward movement of the motor arm 78 and reduce bouncing behavior. After contact is established between grinding wheel 36 and skate blade 142, the soft start routine can be configured to ramp up the speed of the grinding motor 80 to full speed, which can result in a smooth translation of the grinding wheel 36 during operation without bouncing. The soft start routine can be configured to help eliminate dangerous conditions, such as, the grinding ring 36 hitting the jaws holding the skate blade or the grinding ring 36 hitting a steep skate blade 142, which could break or damage one or more components of the sharpener (such as, the jaws) or damage the skate blade 142. In some embodiments, the soft start routine can smooth the power consumption across the heel which can result in more even material removal rate on all sections of the skate.
Prior to contact with the skate, the control system can monitor the current drawn by the grinding motor and can establish a baseline current of the system. The baseline current represents the amount of current, and thus power, used by the grinding motor 80 prior to the grinding wheel 36 contacting the skate blade 142. The baseline current can vary each time the skate sharpener is operated, during grinding operations, and between different systems. Some factors that may contribute to variations in a baseline current can include, but is not limited to, slight differences between motors and in-part tolerances (such as, bearings of the grinding spindle), temperatures of the motor and spindle, wear of mechanical and electrical components, and/or other factors may influence variations in current. In some embodiments, the baseline current can be established over a period of between 0.5 seconds to 3 seconds. In some embodiments, the baseline current may be determined in less than one second, under two seconds, under 3 seconds, or another time period. In some embodiments, baseline current determination may be delayed during initial startup (such as, a cold start) of the motor for a defined period of time in order for the system to arrive a steady state. The delay can help to filter out transient power fluctuations that may be experienced during start-up and allow time for the skate sharpener to attain a steady state of operation.
When the grinding wheel makes contact with the skate, the grinding motor 80 may naturally slow down due to the load applied to the grinding wheel 36 via friction and resistance on the motor's output spindle 82. When the grinding motor 80 slows down, the back EMF generated by the grinding motor 80 is reduced, which results in an increase in the current flowing to the grinding motor 80. The control unit 32 of the skate sharpener can monitor the current and can detect the increase in current. The control unit 32 can implement a threshold over the baseline current to determine whether the grinding wheel is in contact with the skate blade 142. The threshold can be a percentage of the baseline (such as, for example, a 10% increase of the baseline current), a static value (such as, for example, an increase of 200 mA over the baseline current), a rate of increase in the current (such as an increase of 200 mA in 0.1 seconds), and/or other threshold configured to detect contact between the grinding wheel and the skate blade. The current value data, as measured by the control unit, may be filtered or smoothed in order to reduce electromagnetic noise and/or mechanical vibration in order to generally improve the ability to detect contact with the skate.
After contact between the skate and the grinding wheel has been detected, the control unit 32 can ramp the speed of the grinding motor 80 to a higher speed, which may be full speed in a relatively short period of time. For example, in one embodiment, the speed of the grinding wheel 36 may be increased from 1000 rpm to 8000 rpm over a period of 0.55 seconds. The rotational speed of the grinding wheel 36 may be controlled using various control algorithms, such as Pulse Width Modulation (PWM) or other algorithms known in the art for controlling rotational speed of an electric motor. The ramp from the intermediate speed to full speed can use a linear, exponential, or other ramp algorithm configured to help reduce bounce while increasing speed and maintaining a smooth transition. The soft start routine can be implemented using open loop or closed loop control of ramp speed. The implementation of a soft start routine is not limited to the grinding motors described herein, and can be implemented with various types of electric motors that can be configured to modulate the speed of the electric motor.
In some embodiments, the bounce experienced by the system can be greater in one direction, for example moving from right to left or visa-versa. When the grinding wheel traverses over the left side (moving right to left or left to right) of the skate, the bounce can be significantly less because interface forces are decreased at the left side of the skate due to such factors as the direction of rotation, location of the pivot point, and the side of the grinding ring where frictional forces are generated. When the grinding wheel returns to its home position off the right edge of the skate, the direction of rotation of the grinding wheel causes an increase in the force driving the grinding wheel into the skate.
In some embodiments, it can be beneficial for the soft start routine to implement a lower grinding speed on the right edge (heel) of the skate. This lower grinding speed can result in a decrease in material removal rate on the right to left pass which can help neutralize the higher removal rate of material from the heel by the grinding wheel during the left to right pass. The result can be a more uniform material removal rate along the length of the skate. It should also be appreciated that the soft start routine can be used on the initial approach and contact with the skate blade on either end of the skate (e.g., right or left, heel or toe).
After the grinding wheel returns to the home position, the soft start routine can be reinitiated to allow the grinding motor to spin down to a lower intermediate speed, in accordance with the operational parameters of the grinding operation, and repeat the soft start routine on a subsequent pass of the skate blade 142. The baseline current can be reestablished for each cycle in order to compensate for possible changes in the baseline current. For example, the current to the motor can change as the motor and spindle heat up from use.
In some embodiments, the control unit 32 can detect contact between the grinding wheel 36 and the skate blade 142 using various alternative methods and systems. In some embodiments, an electrical proximity or contact sensor can detect contact between the skate blade 142 and grinding wheel 36. In some embodiments, a speed sensor (such as, for example, hall effect sensors, optical switches, encoders, and the like) can measure the grinding wheel 360 and/or motor speed to detect when the speed of the grinding wheel and/or motor reduces. In some embodiments, a tilt-sensor or accelerometer mounted on the control arm 78 can detect when the control arm 78 starts to move downward and/or detect vibration levels in the control arm 78. In some embodiments, back EMF generated by the motor can be measured by sampling motor voltage generation when spinning to determine when the back EMF decreases by a threshold amount. In some embodiments, a torque sensor (e.g., piezo or strain gauge) on the motor output or grinding motor spindle shaft 82. The control unit 32 may implement one or more of the above contact detection systems in place of, or in addition to, the current baseline detection routine described above.
In some embodiments, the control unit 32 can record the position of the speed ramp up and can apply a similar ramp down when the grinding wheel is returning to its home position off the trailing edge of the skate blade 142. The ramp down can help provide a more uniform grinding power and material removal rate. In some embodiments, a stepper motor can facilitate implementation of the ramp down by correlating the current sensing of the contact detection to a specific location in the grinding wheel travel. In some embodiments, an encoder can be used to detect grinding wheel position or an accelerometer to detect motor arm angle.
In some embodiments, the soft start routine can also be used in an algorithm to change the profile or “rocker” of a skate blade. Changing the profile of a skate can require inconsistent material removal along the skate edge to affect the lengthwise shape of the skate and thus the position of the skate over the skate edge. The soft start can correlate motor current information (or other motor power measurements) with location along the length of the skate. The information gathered by the soft start routine can be used to selectively remove more or less skate material from a given segment of the blade.
In some embodiments, the soft start routine can be used to increase translation speed of the grinding wheel as compared to systems that do not use a soft start routine. For example, after the grinding wheel smoothly contacts the skate, the rotational speed of the grinding wheel 36 and the translation speed may be ramped up to speeds above what would be capable on a system using a uniform grinding speed during the grinding operation.
In some embodiments, the soft start routine can adjust the speed to account for the safe operation of grinding wheels having various grit levels. Without a soft start routine, a sharpening system may need to select a slower grinding ring speed based on the most aggressive grinding wheel that can be used with the system. The soft start routine can compensate for grinding rings of various grits by ramping up to full speed after smooth contact with the skate and without producing a potentially destructive bounce.
In some embodiments, the soft start routine can be disabled. For example, users of the sharpening system may use a skate type with the sharpening system that is not conducive to the Soft Start routine. In such situations, the user may disable the soft start routine in favor of sharpening at a constant grinding speed.
At block 602, the control unit 32 receives input to initiate a grinding operation. The input may be received from an operator manually providing the input by pressing an input key, such as a start button. In some embodiments, the input may be a signal received from a remote source configured to initiate the operation of the skate sharpener.
At block 604, the control unit 32 begins operating the grinding motor 80 at a determined contact speed and begins translating the grinding wheel 36 toward the skate blade 142 from the home position for execution of the grinding operation. The grinding motor 80 may initially operate at a contact speed, such as 500 rpm, 1000 rpm, 1500 rpm, 2000 rpm, 2500 rpm, 3000 rpm, 3500 rpm and/or number between the ranges. The contact speed can be a lower speed than the operational grinding speed of the grinding operation. The grinding motor 80 can operate at the contact speed as the grinding wheel 36 travels a distance between the home position toward the contact position of the skate blade 142.
At block 606, the control unit determines the baseline current of the grinding motor 80 prior to contact with the skate blade 142. The control unit 32 can monitor the current supplied to the grinding motor 80 and can determine a baseline current of the grinding motor 80. The baseline current represents the amount of current used by the grinding motor 80 prior to the grinding wheel 36 contacting the skate blade 142. The baseline current can vary between skate sharpeners, between passes during the grinding operation, and between uses of the same skate sharpener. In some embodiments, the baseline current can be determined each time the grinding wheel executes a pass of grinding operation from the home position. In some embodiments, the baseline current can be established in less than 0.5, less than 1 second, less than 2 seconds, less than 3 seconds, and/or within any combination of ranges of the above listed time periods. In some embodiments, such as during initial startup, the determination of the baseline current may be delayed for a defined period of time in order for the skate sharpener to reach steady state operation. Delaying the determination can help to filter out transient power fluctuations that may be experienced during start-up and prior to attaining a steady state of operation.
At block 608, the control unit can detect contact between the grinding wheel 36 and the skate blade 142 based on an increase in current to the grinding motor 80 over the baseline current by a threshold amount. When the grinding wheel 36 makes contact with the skate, the grinding motor 80 may slow down due to the load applied to the grinding wheel 36 via friction and resistance on the motor's output spindle 82. When the motor 80 slows down, the back EMF generated by the motor 80 is reduced, which results in an increase in the current flowing to the motor. The control unit 32 can monitor the current and detect when the current increases over a defined threshold. The threshold can be a percentage of the baseline (such as, for example, a 10% increase of the baseline current) or a static value (such as, for example, an increase of 200 mA over the baseline current).
At block 610, the control unit can increase the speed of the grinding motor to an operational grinding speed. The operational grinding speed can be greater than 5000 rpm, 6000 rpm, 7000 rpm, 8000 rpm, and/or any other speed greater than the contact speed, as defined by the operational parameters of the grinding operation. The rotational speed of the grinding wheel 36 may be controlled using various control algorithms, such as Pulse Width Modulation (PWM) or other algorithms known in the art for controlling rotational speed of the grinding motor. The ramp from the intermediate speed to full speed can use a linear, exponential, or other ramping algorithm to increase speed while reducing bouncing of the grinding wheel on the skate. The increase in operational speed can be implemented in a relatively short amount of time. For example, in one embodiment, the speed of the grinding wheel may be increased from 1000 rpm to 8000 rpm over a period of 0.55 seconds. Operation of the grinding motor can be implemented using open loop or closed loop control systems.
At block 612, the control unit continues execution of the grinding operation in accordance with operational parameters until the grinding wheel traverses to the end stop of the skate sharpener. In some embodiments, the grinding operation applies a constant grinding force along the entire length of the skate. In some embodiments, the grinding operation may apply a varied grinding force along the length of the skate. For example, a grinding operation may be configured to alter the profile of the skate. In such an instance, non-uniform amounts of material are removed along the length of the skate.
At block 614, the control unit continues execution of the grinding operation in accordance with operational parameters until the grinding wheel traverses from the end stop to the home stop of the skate sharpener. In some embodiments, the bounce of the grinding wheel relative to the skate blade experienced by the system can be greater in one direction, for example moving from the home location to the end of the pass or visa-versa. In some embodiments, when the grinding wheel 36 traverses from the end location to the home location, the bounce can be significantly less because interface forces can be decreased on the end stop side of the skate due to factors, such as the direction of rotation of the grinding wheel 36, location of the pivot point, and the side of the grinding wheel 36 where frictional forces are generated. The rotational speed of the grinding wheel 36 can be the same in both directions. In some embodiments, the rotational speed will be different for each direction in accordance with the operational parameters of the grinding routine. In some embodiments, the control unit 32 can apply a ramp down when the grinding wheel is returning to its home position off the trailing edge of the skate. The ramp down can help provide a more uniform grinding power and material removal rate.
At block 616, after the grinding wheel returns to the home stop, the control unit determines whether the grinding routine is complete. If the grinding routine is complete the process ends. If the grinding routine is not complete the process returns to block 604 to complete another pass. If another pass is going to be initiated, the soft start routine can be reinitiated to allow the grinding motor to spin down to a lower intermediate speed, in accordance with the operational parameters of the grinding operation, and repeat the soft start routine on the subsequent pass. The baseline current can be reestablished for each cycle in order to compensate for possible changes in the baseline current.
In some embodiments, the skate sharpener can determine whether the skate blade is in contact with the grinding wheel during the skate sharpening process. In most skate sharpening systems, the sharpening of a single blade requires multiple cycles of the grinding wheel across the surface as this allows for the best balance of material removal and surface finish. It is generally desirable to make the cycle time as short as possible so as to make the sharpening procedure as quick as possible. This is particularly important in commercial operations where the cycle time represents throughput of the machine and potentially increased revenue.
The sharpener can detect when the grinding ring leaves the skate blade after making a pass across the skate. Because the skate sharpener can detect that the grinding ring has left the skate blade, the skate sharpener can reverse the translation direction sooner than it would have otherwise been able to if the system were waiting for the sensor at the end stop of the skate sharpener. This early reversal can save the user a significant amount of time on each pass of a sharpening cycle.
In some embodiments, the control system can be configured to detect a drop in motor current over a defined period of time to indicate that the grinding wheel is no longer in contact with the blade. For example, the drop in motor current can be greater than or equal to about 0.1 amps and less than or equal to about 2.0. In some embodiments, the drop in amps can be at least about 0.8, between 0.1 and 0.8, between 0.1 and 1.2, 0.8 and 2.0, or any range of the foregoing ranges. The defined period of time can be in a period of time of about 0.1 seconds, 0.5 seconds, 1 second, 2 seconds, 3 seconds, 5 seconds, another defined time period, or a range of time periods.
In some embodiments, the control system may be configured to determine whether the motor current drops below a previously determined threshold, such as illustrated in
A threshold may be used with or without a time requirement. For example, as illustrated in
When the control system determines that the grinding wheel is no longer in contact with the skate blade, the translation direction may then be reversed, eliminating the wasted travel time for the grinding wheel to reach the end of travel limit switch and return to the skate again. It can be appreciated that the smaller the skate blade, the more time is saved by not traversing to the end stop of the skate sharpener. The detection of the end of the skate blade can be used at either end of the skate.
In some embodiments, the skate detection routine can be disabled. For example, users of the sharpening system may use a skate type with the sharpening system that is not conducive to the skate detection routine. In such situations, the user may disable the skate detection routine in favor of sharpening all the way to the sensor at the end stop of the skate sharpener.
In some embodiments, in the event the grinding motor and the control unit do not detect contact with the skate after a predetermined amount of time, either on the pass from left to right or right to left, the system can halt the grinding motor and/or return the grinding ring to the home position. The benefit of stopping the grinding wheel in this scenario could be to prevent travel of the grinding ring when a skate is not inserted and/or ensure that the grinding ring will not make contact with parts of the machine that could be in the way of the grinding wheel if a skate is not inserted. An example of a feature on the system to avoid would be the skate clamp jaws without a skate loaded.
At block 702, the control unit 32 receives input to initiate a grinding operation. The input may be received from an operator manually providing the input by pressing an input key, such as a start button. In some embodiments, the input may be a signal received from a remote source configured to initiate the operation of the skate sharpener.
At block 704, the control unit 32 begins operating the grinding motor 80 at a determined contact speed and begins translating the grinding wheel 36 toward the skate blade 142 from the home position for execution of the grinding operation. The grinding motor 80 may initially operate at a contact speed, such as 500 rpm, 1000 rpm, 1500 rpm, 2000 rpm, 2500 rpm, 3000 rpm, 3500 rpm and/or number between the ranges. The contact speed can be a lower speed than the operational grinding speed of the grinding operation. The grinding motor 80 can operate at the contact speed as the grinding wheel 36 travels a distance between the home position toward the contact position of the skate blade 142.
At block 706, the control unit can detect contact between the grinding wheel 36 and the skate blade 142 based on an increase in current to the grinding motor 80 over the baseline current by a threshold amount. When the grinding wheel 36 makes contact with the skate, the grinding motor 80 may slow down due to the load applied to the grinding wheel 36 via friction and resistance on the motor's output spindle 82. When the motor 80 slows down, the back EMF generated by the motor 80 is reduced, which results in an increase in the current flowing to the motor. The control unit 32 can monitor the current and detect when the current increases over a defined threshold. The threshold can be a percentage of the baseline (such as, for example, a 10% increase of the baseline current) or a static value (such as, for example, an increase of 200 mA over the baseline current).
In some embodiments, the control unit can determine a baseline current of the grinding motor 80 prior to contact with the skate blade 142. The control unit 32 can monitor the current supplied to the grinding motor 80 and can determine a baseline current of the grinding motor 80. The baseline current can represent the amount of current used by the grinding motor 80 prior to the grinding wheel 36 contacting the skate blade 142. The baseline current can vary between skate sharpeners, between passes during the grinding operation, and between uses of the same skate sharpener. In some embodiments, the baseline current can be determined each time the grinding wheel executes a pass of grinding operation from the home position. In some embodiments, the baseline current can be established in less than 0.5, less than 1 second, less than 2 seconds, less than 3 seconds, and/or within any combination of ranges of the above listed time periods. In some embodiments, such as during initial startup, the determination of the baseline current may be delayed for a defined period of time in order for the skate sharpener to reach steady state operation. Delaying the determination can help to filter out transient power fluctuations that may be experienced during start-up and prior to attaining a steady state of operation.
After detection of the skate blade, the control unit can continue with the grinding operation along the length of the skate blade. In some embodiments, the control unit can increase the speed of the grinding motor to an operational grinding speed. The operational grinding speed can be greater than 5000 rpm, 6000 rpm, 7000 rpm, 8000 rpm, and/or any other speed greater than the contact speed, as defined by the operational parameters of the grinding operation. The rotational speed of the grinding wheel 36 may be controlled using various control algorithms, such as Pulse Width Modulation (PWM) or other algorithms known in the art for controlling rotational speed of the grinding motor. The ramp from the intermediate speed to full speed can use a linear, exponential, or other ramping algorithm to increase speed while reducing bouncing of the grinding wheel on the skate. The increase in operational speed can be implemented in a relatively short amount of time. For example, in one embodiment, the speed of the grinding wheel may be increased from 1000 rpm to 8000 rpm over a period of 0.55 seconds. Operation of the grinding motor can be implemented using open loop or closed loop control systems.
At block 708, the control unit can detect loss of contact between the grinding wheel 36 and the skate blade 142 based on a decrease in current to the grinding motor 80. In some embodiments, the control unit can determine loss of contact when there is a drop in motor current over a defined period of time. In some embodiments, the control unit can determine when the motor current drops below a threshold amount. The control unit 32 can monitor the current and detect when the current decreases below the defined threshold. The threshold may be calculated relative to the current level while the grinding ring was in contact with the skate and/or relative to when the grinding wheel was not touching the skate. In some embodiments, the control system may determine whether the motor current has stabilized below a current threshold to indicate that the grinding wheel is not contacting the skate blade.
At block 710, the control unit reverses direction of translation of the grinding wheel to move in the opposite direction. In some embodiments, the reversal of direction of the grinding wheel after detection may be delayed by a defined period of time to help ensure that the grinding wheel has completely lost contact with the skate blade.
At block 712, the control unit continues execution of the grinding operation in accordance with operational parameters until the grinding wheel traverses toward the home stop of the skate sharpener. In some embodiments, the bounce of the grinding wheel relative to the skate blade experienced by the system can be greater in one direction, for example moving from the home location to the end of the pass or visa-versa. In some embodiments, when the grinding wheel 36 traverses from the end location to the home location, the bounce can be significantly less because interface forces can be decreased on the end stop side of the skate due to factors, such as the direction of rotation of the grinding wheel 36, location of the pivot point, and the side of the grinding wheel 36 where frictional forces are generated. The rotational speed of the grinding wheel 36 can be the same in both directions. In some embodiments, the rotational speed will be different for each direction in accordance with the operational parameters of the grinding routine. In some embodiments, the control unit 32 can apply a ramp down when the grinding wheel is returning to its home position off the trailing edge of the skate. The ramp down can help provide a more uniform grinding power and material removal rate.
At block 714, the control unit can detect loss of contact between the grinding wheel 36 and the skate blade 142 prior to returning to the home position in the same manner as described with respect to block 708. At block 716, the control unit can determine whether the grinding operation is complete. If the grinding routine is complete, the control unit translates the grinding wheel back to the home stop and the process ends. If the grinding routine is not complete the process returns to block 704 to complete another pass.
In some configurations, the door 30, 1030 can include a window 31, 1031 or the like. The window 31, 1031 can be a majority of the door 30, 1030 or can be a small portion of the door 30, 1030. The window 31, 1031 provides light transmissivity between the inside and the outside of the skate sharpener 10, 1010. In some configurations, the window 31, 1031 is transparent. In some configurations, the window 31, 1031 is translucent. In some configurations, the window 31, 1031 is other than opaque.
Because of the ability for light to be transmitted from inside of the skate sharpener to outside of the skate sharpener, it is possible to provide a general indication of one or more states of operation of the sharpening system to the user through the window. For example, in some configurations, one or more light sources can be provided within the sharpening system. In one configuration, a multi-colored light strip can be provided just inside of the door. The light strip can be used to indicate various operating conditions of the sharpening system. For example, red can be used to indicate an error or a need for attention (e.g., slot covers not engaged with skate blade or blade holder), orange can be used to indicate a need for input into a user interface, white can be used to indicate that the door is open and green can be used to indicate that a skate sharpening process has been completed. Other indications can be used and other conditions also can be indicated. In some configurations, a flashing pattern can be used instead of discrete colors.
While various embodiments of the invention have been particularly shown and described, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.
Any and all applications for which a foreign or domestic priority claim is identified in the Application Data Sheet as filed with the present application are hereby incorporated by reference under 37 C.F.R. §1.57. This application is a continuation-in-part under 35 U.S.C. §120 of each of the following U.S. patent applications, each of which is hereby incorporated by reference in its entirety: U.S. patent application Ser. No. 14/523,407, filed 24 Oct. 2014 [Docket No. SPARX.003A]; U.S. patent application Ser. No. 14/523,453, filed 24 Oct. 2014 [Docket No. SPARX.004A]; U.S. patent application Ser. No. 14/523,463, filed 24 Oct. 2014 [Docket No. SPARX.005A]; U.S. patent application Ser. No. 14/523,476, filed 24 Oct. 2014 [Docket No. SPARX.006A]; U.S. patent application Ser. No. 14/523,483, filed 24 Oct. 2014 [Docket No. SPARX.007A]; U.S. patent application Ser. No. 14/805,772, filed 22 Jul. 2015 [Docket No. SPARX.008.C1], which is a continuation of U.S. patent application Ser. No. 14/523,489, filed 24 Oct. 2014 and issued as U.S. Pat. No. 9,114,498 on 25 Aug. 2015 [Docket No. SPARX.008A]; U.S. patent application Ser. No. 14/523,499, filed 24 Oct. 2014 [Docket No. SPARX.009A]; U.S. Design patent application Ser. No. 29/532,597, filed 8 Jul. 2015 [Docket No. SPARX.014DA]; U.S. Provisional Patent Application No. 62/129,095, filed 6 Mar. 2015 [Docket No. SPARX.016PR]; U.S. patent application Ser. No. 14/723,564, filed 28 May 2015 [Docket No. SPARX.017A]; International Application No. PCT/US2015/057078, filed 23 Oct. 2015; and U.S. Provisional Patent Application No. 62/335,003, filed 11 May 2016 [Docket No. SPARX.017PR2].
| Number | Date | Country | |
|---|---|---|---|
| 20170355056 A1 | Dec 2017 | US |
| Number | Date | Country | |
|---|---|---|---|
| 62129095 | Mar 2015 | US | |
| 62335003 | May 2016 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 14523489 | Oct 2014 | US |
| Child | 14805772 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/US2015/057078 | Oct 2015 | US |
| Child | 15494412 | US | |
| Parent | 14523453 | Oct 2014 | US |
| Child | PCT/US2015/057078 | US | |
| Parent | 14523407 | Oct 2014 | US |
| Child | 14523453 | US | |
| Parent | 14805772 | Jul 2015 | US |
| Child | 14523407 | US | |
| Parent | 14523483 | Oct 2014 | US |
| Child | 14523407 | US | |
| Parent | 14523476 | Oct 2014 | US |
| Child | PCT/US2015/057078 | US | |
| Parent | 14523463 | Oct 2014 | US |
| Child | 14523476 | US | |
| Parent | 14523483 | Oct 2014 | US |
| Child | 14523463 | US | |
| Parent | 14523499 | Oct 2014 | US |
| Child | 14523483 | US | |
| Parent | 14723564 | May 2015 | US |
| Child | 14523499 | US | |
| Parent | 29532597 | Jul 2015 | US |
| Child | 14723564 | US |
