Embodiments of the present invention are related generally to banding tools, and in particular to a method and apparatus for tensioning a band with a tool having separate locking and cutting mechanisms that allows for a smaller dimensioned tool, which enhances access to a greater variety of work pieces, and that reduces impact forces felt by the work piece. The tool of the present invention accommodates a variety of band and lock styles. Embodiments of the present invention also include data output functionality, sensors and feedback mechanisms to ascertain performance and predict problems or maintenance issues.
Many types of bands have been devised or advanced for use in clamping objects, such as hoses, pipes, poles, cables and the like. Bands generally are combined with an associated buckle, clasp, clamp, seal or other locking member (collectively referred to herein as a buckle for simplicity) that maintains the wrapped band in a tensioned state about one or more objects. The buckle may be separate from or integral with the band. Bands may be pre-formed prior to installation, in which the band is wrapped about itself to form a closed loop, with the leading or free end of the band positioned through and extending away from the buckle. Such pre-formed bands are subsequently placed about a work piece, i.e., the objects to be bound, and then fully tightened using a clamping tool. Alternatively, some bands are not pre-formed but include a free end that is initially wrapped about the work piece to form a closed loop about the work piece, wherein the leading or free end is then introduced into the buckle by the operator. A tool is typically used to complete tensioning to the desired or specified level.
Various devices have been implemented or disclosed that are intended to enhance or facilitate band tensioning. These devices may be stationary or fixed in position or they may be hand-held. In many instances, such devices also cut off the leading portion of the band after it has been tensioned and create the lock between the band and buckle that maintains the desired tension of the band about the clamped object. Devices that perform the tightening, locking and cutting functions may be manual, pneumatic, electric or a combination thereof in operation. Pneumatic and electric devices accomplish the tasks of tensioning, locking and cutting with limited or reduced human effort. Band tightening devices that are pneumatic or electric are usually semiautomatic in that the operator is required to perform some, but not all, of the tasks or associated operations. Manual tasks that remain may include locating the band about the object, inserting or otherwise locating the leading end of the band relative to or through a buckle and positioning the leading end in a tensioning device to initiate tightening of the band about a work piece. In one known pneumatic band tightening apparatus, a desired tension is preset. A pneumatic cylinder is activated to engage and pull on the band until a desired band tension is reached. Pneumatic control may also be involved in forming the lock and cutting the excess leading end portion after the band is tightened and secured with the buckle.
Although a variety of clamping devices have been designed for use with bands of various sizes, it would be advantageous to provide a device that achieves greater control over the band clamping operations. Such a device should be effective and efficient in tightening the band, forming the lock or clamping function and automatically cutting and removing the excess leading portion after the band is locked. Furthermore, it would be beneficial for such a device to be easily used by the operator in connection with positioning of the clamping device relative to the work piece, including facilitating insertion or engagement of the band to the device. It would also be advantageous to provide a device that locks the band relative to the buckle and cuts the tail of the band in an efficient manner that reduces shock loads while collecting and outputting relevant process data related to installation of each band to verify and distinguish between a properly or improperly installed band and/or to identify maintenance issues with respect to the tool.
It is one aspect of the present invention to provide an adjustably mounted clamping tool or device. More specifically, embodiments of the present invention are interconnected to a stationary slide that allows movement of the tool relative to a fixed base. Further, the clamping device is also capable of pivoting with respect to the base. This functionality allows the operator to more easily access bulky or cumbersome work pieces. For example, with the work piece secured in a vise or otherwise stabilized, the clamping device or tool may then be positioned relative to the object being clamped. The operator is not required to manipulate the position of a work piece relative to the clamping tool. This functionality allows the tool to be placed closer to the work piece and allows for more accurate placement and securement of the band about the object. Further, the adjustable positioning provided by embodiments of the present invention enhances operational repeatability when conducting the same clamping operation over and over.
In one embodiment of the present invention, a gripping mechanism or subassembly will engage a leading end portion of a looped band that has previously been fed through a buckle and placed about a work piece. Once gripped, the band is then tightened about the work piece by a belt tightening mechanism. During tightening, the buckle is secured and restrained by a portion of the tool in preparation for locking the band with respect to the buckle. In a separate process, a punch mechanism or subassembly deforms the band and/or the buckle to secure the band about the workpiece with the desired clamping force and a cutting mechanism or subassembly cuts the excess leading portion of the band.
It is another aspect of the present invention to provide a clamping device utilizing a pair of opposed wheels to grip and tension the band. In one embodiment, one wheel (the tension wheel) is fixed in position and the other wheel (the pinch wheel or backing wheel) is movable to pinch the band between the two wheels. Preferably, both wheels are provided with a textured surface to engage and grip the surface of the band. One or both of the textured surfaces may form a series of teeth or edges that are positioned at an angle relative to the surface of the band to facilitate gripping and tensioning. However, the teeth or edges may have a tendency to puncture or cut the band as it is tensioned, particularly if the teeth or edges of the teeth extend continuously or near continuously across the entire width of the band, which essentially creates a knife edge across the width of the band. More specifically, the teeth or edges may deform the band by reducing or thinning the cross-sectional area of the band. This reduction of the cross-sectional area will increase the axial stress on the band at this weakened area during tensioning, which may cause premature breaking with the band under tension. For this reason, it is preferred not to have teeth or edges that extend across the entire engaging surface of the tension wheel. Therefore, one or more circumferential grooves may be formed in the textured pattern to create a discontinuity in the edges formed by the teeth. Embodiments of the present invention thus employ a tension wheel having an engaging surface with non-continuous teeth relative to the width of the band, thereby addressing this problem.
As previously noted, it is desirable that the engaging surfaces of both the tension and pinch wheels are textured. If the tension wheel is textured with a toothed pattern, the pinch wheel is preferably provided with a diamond patterned surface. As compared to a toothed pattern, a diamond pattern typically is formed by pyramid shaped teeth whose apex may be a point rather than an edge. Some embodiments of the present invention may employ an apex comprising a concave, convex or planar surface. Further, other pyramid-like shapes may be used without departing from the scope of the invention, such as a tetrahedron (three-sided pyramid), a five-sided pyramid, etc. When a diamond pattern is formed on the pinch wheel and a toothed pattern is formed on the opposed tension wheel, it is a related aspect of the present invention to stagger the diamond pattern relative to the toothed pattern such that the apex of the teeth and the apex of pyramids forming the diamond pattern are not aligned. For example, the edges formed by the teeth of the tension wheel and the points formed by the diamond pattern of the pinch wheel are positioned such that the points of the diamond pattern are aligned with the space or gaps between successive edges of the toothed pattern, as opposed to a configuration where the points and edges are aligned to abut each other. This configuration reduces the chances of thinning and severing the band prematurely. It should also be appreciated that the diamond pattern may be formed on the tension wheel and that the toothed pattern may be formed on the pinch wheel. Alternatively, other textured patterns may be appropriate as well.
There are advantages that come from texturing the surface of both the tension and pinch wheels. For example, placing a texture pattern on each wheel also produces less metal shavings. In prior art devices, where one wheel employs a textured surface and the other wheel employs a smooth surface, the smooth surface is susceptible to slipping on the band, which can create metal shavings. Over time, the shavings may fill the gaps between the rows of teeth in the textured pattern of the opposed wheel, thereby decreasing the gripping action of the teeth of the opposed wheel. Also, by offsetting the edges of the tension wheel teeth and the points of the diamond surface of the pinch wheel, the points and teeth tend to self clean the spaces or gaps between the teeth and the points to reduce the accumulation of shavings and prolong the life of the wheels.
Another advantage of the opposed surface patterns of the tension and pinch wheels is derived from cold working both surfaces of the band. In prior art devices, which utilize one smooth wheel in combination with a textured wheel, the surface of the band in contact with the textured wheel is subjected to a greater degree of cold working compared to the surface of the band in contact with the smooth surface of the exposed wheel. This one-sided or uneven cold working of the band causes it to excessively curl. Excessive curling can cause the band to re-enter the device and bind or jam the mechanics. By cold working both surfaces of the band to generally the same extent, due to both the tension and pinch wheel surfaces being textured, excessive curling of the band is reduced.
Embodiments of the present invention also employ a method of interconnecting the tension wheel to a drive shaft in a way that prevents the tension wheel from being mounted incorrectly, thereby avoiding the possibility that the textured surface of the tension wheel is incorrectly oriented. More specifically, tension wheels of the prior art are typically interconnected to their respective drive shafts via a traditional key and key-way method. However, this method of interconnection does not prohibit the tension wheel from being position on the drive shaft backwards. If the tension wheel is positioned on the shaft with the texturing pattern in the incorrect orientation, the band may not be adequately engaged or gripped since the texturing pattern will often be angled away from the band surface such that the tension wheel slips rather than engages the band surface. Also, the key traditionally used is an additional element or component that adds cost and complexity to assembly of the device. Embodiments of the present invention employ a tension wheel having an eccentric inner diameter and a correspondingly configured drive shaft that can only fit together in one way. In this manner, a component is eliminated and the tension wheel will always be correctly oriented with the textured pattern facing the proper direction.
It is yet another aspect of the present invention to provide an improved tensioning system that employs an automated and variable range of band pinching forces. As described above, a movable pinch wheel is used to press the band against the tension wheel in order to grip the band for tensioning. In order to achieve an effective pressing force, embodiments of the tensioning subassembly employ a pneumatic pinch cylinder interconnected to the pinch wheel via a toggle arm or pivoting pinch arm. One skilled in the art will appreciate that instead of a pneumatic cylinder, a servo motor, solenoid motor or other selective positioning method may be employed to transition the pinch wheel from a release position to an engaging position. As the pinch cylinder is actuated, the cylinder rod travels or extends outwardly. The pinch arm or toggle arm will then rotate about a pivot point, causing the opposite end of the pinch arm to move the pinch wheel into engagement with the band and to apply the requisite force needed for the tension wheel to grip the band. The length of the toggle arm and the location of the pivot can vary to increase or decrease the mechanical leverage of the pinch cylinder and thereby increase or decrease the force applied by the pinch wheel on the band. In addition, rather than having a set stroke length designed to apply a predetermined force to the band, the pinch cylinder is designed to have excess stroke length and is designed to halt travel of the cylinder rod when the desired force is applied to the band. A sensor or feedback loop associated with the pinch cylinder identifies when the desired force is applied and halts further travel of the cylinder rod. Importantly, the additional or excess stroke length permits the system to accommodate wear of the textured surfaces of the tension and/or pinch wheels. As wear occurs and the effective diameter of one or both wheels is reduced, additional stroke is available to move the pinch wheel closer to the tension wheel and thereby maintain appropriate gripping pressure on the band. Further, the stroke of the pinch cylinder may be automatically monitored over time and provide feedback concerning the wear of the tension and/or pinch wheels advising the operator of when it is time to replace one or both of the wheels before it may be visually obvious.
It is another aspect of the present invention to provide an improved system for tightening and adjusting the belt that drives the tension wheel. More specifically, prior art systems for band tensioning often utilize a tension wheel that is powered by a belt drive rather than directly powered by a motor. When a belt drive is used, the belt must be properly tensioned for the system to function correctly. Over time the belt drive may loosen, thereby reducing the effectiveness or ability of the motor and its associated drive wheel to rotate the tension wheel and effectively grip and tension the band. Alternatively, because the invention may be used with different sized bands, it may be desirable to apply different tensions. To maintain an appropriate tension on the drive belt, prior art belt tensioning systems typically use an adjustably positionable idler pulley in contact with the belt to remove slack. The idler pulley typically is repositionable in a slot oriented perpendicular to the path of the belt. Thus, as the idler pulley applies a tensioning force against the belt, the belt applies a reactive force against the idler pulley. A disadvantage of this configuration is that the full reactive force of the belt on the pulley is aligned with the slot in which the idler pulley is positioned and secured. As a result, the combination of vibration of the tool and the force of the belt acting on the idler pulley may eventually cause the mounting of the idler pulley to loosen and, once loosened, move the idler pulley in such a way that reduces the tension of the belt. Because of the orientation of the slot in which the idler pulley is mounted, the idler pulley can often only move directly away from the belt. Relatedly, it is also difficult to increase tension on the belt in these types of tensioning systems. The idler pulley may only move in a direction directly opposed to the reactive face of the belt. Making fine adjustments in the tension of the belt is difficult under these circumstances.
In comparison, embodiments of the present invention utilize at least one belt idler pulley positioned in a slot oriented parallel to the path of the belt, rather than perpendicular to the path of the belt. This orientation differs from the prior art in that the reactive force generated by the belt on the idler pulley is not fully aligned with the slot in which the idler pulley is mounted. Instead, the reactive force is oriented at an angle relative to the slot, with the component vectors of the belt reactive force oriented both perpendicular and parallel to the orientation of the adjustment slot. With this configuration, the loss of tension in the belt is reduced because only a portion of the reactive force applied by the belt on the pulley is in the direction of the adjustment slot while the remaining reactive force is in a direction that opposes movement of the idler pulley within the adjustment slot. Similarly, in the context of manually adjusting the tension of the belt, the present configuration facilitates tension adjustments. Because the adjustment slot runs parallel to the path of the belt, the idler pulley must be moved a greater distance to achieve the same tension adjustment as a configuration in which the slot is oriented perpendicular to the path of the belt. A longer distance in which to make adjustments allows for finer control and adjustment of tension pressure, which also requires less force to increase the tension on the drive belt since the reactive force generated by the belt does not fully oppose movement of the idler pulley within the adjustment slot.
It is another aspect of the present invention to accomplish punching and locking and cutting or severing the band in a two-step process. More specifically, embodiments of the present invention employ a cam-actuated system for additional control of the punching process that deforms a portion of the band to secure the position of the band relative to the buckle and the cutting process that removes the excess portion of the leading end of the band. This reduces the impact force generated by the punching and cutting operation which, in turn, reduces the impact on the workpiece and the shock felt by the operator. In one embodiment of the present invention, for example, the energy used to drive or power the punch is provided by a spring that is loaded and activated by the action of an associated cam. As the cam is rotated, the spring is loaded. Simultaneously, the punch is maintained in a locked position by at least one spring loaded lock pawl. As the cam continues to travel, impact arms separate the lock pawl(s) from the punch. The released energy of the spring then drives the punch into the band through an aperture in the buckle. In turn, this deforms the band and locks the band periphery relative to the buckle and the work piece.
The punch may also include an associated depth and alignment indicator to indicate that the punch has deformed the band to the requisite depth and that the punch is properly aligned relative to the band. In one embodiment, the punch is provided with a shoulder axially spaced away from the leading edge of the punch. The shoulder forms a ring around the deformed area or dimple in the band to give the operator the visual ability to ascertain the effectiveness of the punch. A symmetrical and fully formed ring indicates the punch properly deformed the band, that the punch was properly aligned relative to the band and that the desired retention force should be achieved. Conversely, a partial or asymmetrical ring indicates a depth and/or alignment problem, requiring the tool to be adjusted. It should be appreciated that the punch may be reconfigured to work with a variety of differently configured bands and buckles. In another embodiment of the invention, the punch may be provided with two separate shoulders spaced apart along the axis of the punch. One indicates a minimum depth of the dimple and the other indicates a maximum depth of the dimple. The quality of the dimple may be ascertained from the markings.
After the band has been punched, the cam continues its motion and interacts with the band cutting subassembly. More specifically, a rotary cutting blade is disposed underneath the band such that, upon further movement of the cam, the blade is caused to rotate and sever leading portions of the band. The motion of the blade also bends or wraps the end of the remaining portion of the band about the buckle forming a secondary or junior lock. The design configuration of the cutting mechanism also reduces the width of the tool increasing the ability of the tool to access a variety of differently shaped work pieces. The rotary-actuated cutting mechanism also reduces the overall height of the tool and resulting impact or shock generated during a cutting operation compared to a toggle-actuated guillotine-style cutting blade. These latter types of cutting mechanisms require a larger impact force to cut the band and also require a certain amount of overtravel of the blade to ensure that the band has been fully cut. Accommodating the overtravel requires a longer linear stroke of the blade which requires a larger housing. A larger impact force generates greater shock and vibration of the band, the tool and the work piece. In contrast, separating the punching and cutting operations reduces the impact loads experienced by the work piece and the operator from what it would be if both operations occurred simultaneously. It further allows the cam subassembly for the punch and cutting operations to be housed in a more compact manner, allowing the tool better improved access to a variety of differently shaped work pieces.
It is a related aspect of the present invention to facilitate clamping a band about a flat object or one that has a flat surface. That is, at least one embodiment of the present invention allows for the buckle to be positioned and held generally flat against a flat work piece. Unlike many prior art devices, the tensioning and locking scheme contemplated by embodiments of the present invention does not require that the buckle be lifted relative to the workpiece for tensioning or locking, which would raise the buckle from the flat surface and increase or lengthen the perimeter length of the band about the work piece resulting in a reduced retention force. By allowing the buckle to remain positioned against the surface of the work piece, the retention or clamping force of the band may be maintained at the desired amount. The ability to maintain the buckle and the band flat against the workpiece is also enhanced because the tail or leading portion of the band is pulled from the buckle at an angle.
It is another aspect of the present invention to monitor and measure multiple components of the overall system to enhance quality and performance of the clamping tool. A load cell associated with the various mechanical linkages forming the band tightening, punching and cutting subassemblies provides this feature. The output of the load cell may be customized to any unit of measurement without departing from the scope of the invention. Further, the output of the load cell may be provided as a function of time. For example, tension in the band over time may be monitored and output, maximum tension in the band may be monitored and output, tension in the band at cut off may be monitored and output, punch impact force may be monitored and output, and the amount of force needed to cut the band may be monitored and output. It is also envisioned that this output may be visual or audible. For example, the output of the load cell may be displayed on a monitor, such as in graphic form, wherein the operator can assess the performance of the tool throughout each cycle thereby monitoring performance and also identifying maintenance and/or repair issues. Lower than expected tension numbers during the band tightening process may suggest the occurrence of slipping tension and pinch wheels. As gripping wheels become worn, it may take longer for the tension to reach the desired level or the desired level may not be achieved. The operator and/or operating software may then identify problems before they influence the end product. In such a case, the tension and/or punch wheels may need replacing or cleaning or the belt drive of the tightening system may be a tension adjustment. Further, if the punch force is low or high, the punch may be misaligned or worn, or the spring member driving the punch may be incorrectly sized or worn. Similarly, when the amount of force needed to cut the band is increased, the cutting blade may need to be cleaned or replaced. The operating software may automatically shut down the tool if the measured data deviates from predetermined values or ranges. The outputted data may be sent to a remote industrial data acquisition and monitoring system or to any other system of displaying, outputting and/or analyzing information. The data may also be saved for long-term information analysis. For example, a running total of the number of bands tensioned and clamped may also be monitored which can provide helpful data for maintaining the tool. Moreover, these parameters may also be compared to optimal parameters for purposes of monitoring system functionality and performance. For example, the data may also be displayed in a graphic form on a monitor, together with an overlaid graph of an ideal load cell output to give an operator near instantaneous feedback.
It is another aspect of the present invention to provide electronic control of the gripping or band tightening mechanism. More specifically, the load cell may be used to ascertain the tension of the band and once the tension of the band achieves a predetermined amount, the punch is automatically activated and the band is cut. While prior art devices use pneumatics to control tensioning, embodiments of the present invention employ pneumatics to control the force applied by the pinch wheel and to control the punching and cutting of the band, but not to tension the band.
It is yet another aspect of the invention to provide a calibration device that may be interconnected to the tool to confirm and calibrate the accuracy of sensors used to measure the tension of the band. In one embodiment, the calibration device includes a sensor, a display and a length of band having one end connected to the sensor and the other end free. The free end is subjected to tensioning by the tool and the tension of the band is measured by the sensor and is displayed. The displayed tension measurement may then be compared to the tension specified for the tool during regular operation. Adjustments to the tool may be made based upon the comparison.
The Summary of the Invention is neither intended nor should it be construed as being representative of the full extent and scope of the present invention. The present invention is set forth in various levels of detail in the Summary of the Invention as well as in the attached drawings and the Detailed Description of the Invention and no limitation as to the scope of the present invention is intended by either the inclusion or non-inclusion of elements, components, etc. in this Summary of the Invention. Additional aspects of the present invention will become more readily apparent from the Detail Description, particularly when taken together with the drawings.
The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and together with the general description of the invention given above and the detailed description of the drawings given below, serve to explain the principles of these inventions.
It should be understood that the drawings are not necessarily to scale. In certain instances, details that are not necessary for an understanding of the invention or that render other details difficult to perceive may have been omitted. It should be understood, of course, that the invention is not necessarily limited to the particular embodiments illustrated herein.
Referring now to
The band gripping and tensioning subassemblies will now be described. As a threshold step, a band 34 is wrapped around one or more objects to be bundled (the work piece) and the leading end of the band 34 is fed through a buckle 36. A band may be wrapped around the workpiece once or multiple times. For stability purposes, the work piece is typically positioned on or affixed to a mount of some sort. As a result, the operator need not worry about stabilizing the work piece but may devote full attention to operating the to tool 2. With specific reference to
Referring now specifically to
Referring now to
Referring again to
Adjacent to and downstream of the tension wheel 38 and pinch wheel 40 is a tail guide 74 that directs an excess portion of the leading end of the band 34 away from the tool device 2 to prevent the tail from re-entering and jamming the mechanical components of the device. Indeed, one of the purposes of providing a textured surface to the pinch wheel 40 is to reduce the amount of curling of the leading edge of the band that occurs when only the tension wheel 38 is textured. With only one wheel textured, one surface of the band is cold worked and the other surface is not. This causes the band to curl. By cold working both surfaces of the band due to both wheels being textured, the band curls less and is less likely to curl in a way that would cause it to re-enter the tool.
Referring now to
The belt 86 is tensioned by a pair of adjustably positionable belt tensioning wheels 96 and 98. While two belt tensioning wheels are preferred, one, three or more could be used. The belt tensioning wheels 96, 98 are positioned in an elongate slot 100 formed in frame 30. The slot is positioned parallel to the path of a segment 86A of the belt 86 running between the drive wheel 84 and the slave wheel 88. Tensioning of the belt 86 is achieved by moving one or both of the belt tensioning wheels 96, 98 along the length of the slot 100, e.g. towards or away from the other belt tensioning wheel. In the embodiment of FIG. 7,. because the toothed belt 86 surrounds two wheels (drive wheel 84 and slave wheel 88), there are two belt segments 86A and 86B extending between the two wheels 84, 86. If the belt 86 surrounded three or more wheels, there would be three or more belt segments extending between the wheels and the individual belt segments may or may not be parallel to each other. According to this aspect of the present invention, the slot 100 would preferably be oriented parallel to at least one of the belt segments or at least not perpendicular to them.
Referring now to
As shown in
With reference to FIGS. 3 and 8-11, an impact mechanism 150 which contains the punching and cutting subassembly mechanisms is mounted at the front of the tool 2 in the illustrated embodiment. The impact mechanism 150 is rotatably mounted between the pair of symmetrical linkages 60 via a pivot 152 (
Once the desired tension is achieved and the band and workpiece have achieved equilibrium, the pneumatic cylinder 170 is actuated, activating the punching and cutting subassemblies, explained in greater detail below. The load cell 154 allows the operator (or system software) to monitor and assess the tension applied to the band, a force profile related to the installation of a band (see
When the pneumatic cylinder 170 is actuated, the cylinder rod 172 moves outwardly, causing interconnected link 174 to rotate about pivot 176. As shown in
As the linkage 174 rotates counterclockwise (as illustrated) due to the outward stroke of the rod 172, the cam surface 178 will push the wheel 180 downwardly, in turn forcing a plunger 182 downwardly. The plunger has an outwardly protruding flange 184 beneath which is captured a spring member 186. The spring member 186 is captured on its opposite end by a shoulder 188 formed in a punch 190. As the cam follower wheel 180 and plunger 182 are moved downwardly, the spring member 186 is loaded or energized. In order to maintain the punch 190 in a loaded condition, at least one locking pawl 192 is employed. The locking pawl 192 is biased to a locked or engaged position with the punch 190 by a biasing spring 194 holding the punch in place and resisting the expansion force of the spring member 186. In particular, as shown in
Still referring to
With reference to
An advantage of the cutting wheel 250 is that it reduces the size and profile of the tool 2, allowing the tool 2 greater versatility in smaller spaces. By locating the blade 256 between two cylinders 252A and 252B, a slot 258 is formed and the band may extend through the slot 258 reducing the size and profile of the cutting mechanism. Further still, the rotary motion of the cutting blade also reduces the stroke and movement required to cut the band compared to the linear movement of a guillotine-type blade. Another advantage of this arrangement is that it provides a tighter, better fitting band on objects with flat surfaces. Because the leading end of the band is pulled or tensioned at an angle relative to the buckle, as shown in
An advantage of the punching and cutting system as described herein is that the locking and cutting functions are performed at separate times. This reduces physical shock associated with punching or deforming the band and/or buckle and severing the tail portion of the band at the same time, as done by prior art devices. More specifically, some prior art devices require a greater force be applied due to the fact that punching and cutting are performed in a single component piece of the banding tool. In some instances, the work piece is held by the operator rather than on a work piece holder. As a result, the impact or repeated impact may injure the operator or lower the quality of the operator's performance. In addition, the increased impact of the prior art devices can have two other negative consequences. It can physically damage or deform the work piece, which may cause the work piece to fail quality control inspection. Conversely, if the work piece is flexible or resilient, the impact of the tool may cause the work piece to apply a reactive force on the tool, causing the tool to recoil and potentially injure the operator. In comparison, the separate cutting function of embodiments of the present invention employs a cutting blade that rotates across the surface of the band rather than being linearly driven through the band. This requires the application of less force to the band which reduces shock on the work piece and results in a better formed cut edge.
Referring now to
The software of the device, or the operator, may review the data 300 to ascertain the status of the band clamping operation. For example, if the maximum tension at 304 is not reached, it may indicate that the pinch wheel and/or tension wheel is not operating correctly. This may be attributed to wear in the pinch wheels, insufficient compression between the pinch wheel and the tension wheel, and/or belt slippage. Further, a tension change in the punching press is also discernible based upon the force required to compress spring member 186. An increase in the amount of tension at 312 may indicate that the punch is worn and may need to be replaced. Conversely, a decrease in the tension at 312 may anticipate a poorly formed locking dimple as the punch may have insufficient force to properly form the dimple. Additionally, an increased tension seen during cutting that exceeds the peak value at 316 may indicate that the cutting blade is working improperly. More specifically, if the increase in tension is excessive, it may indicate that the cutting blade is dull and may need replacement.
In order to ensure the data obtained or monitored by the internal programming of the device is accurate, a calibration device 350 may be periodically interconnected to the tensioning device (
While various embodiments of the present invention have been described in detail, it is apparent that modifications and alterations of those embodiments will occur to those skilled in the art. However, it is to be expressly understood that such modifications and alterations are within the scope and spirit of the present invention, as set forth in the following claims.
This patent application claims the benefit of pending U.S. Provisional Patent Application Ser. No. 61/035,999, filed Mar. 12, 2008 entitled “Stationary Band Clamping Apparatus,” the entire disclosure of which is incorporated by reference herein. This patent application also claims the benefit of pending U.S. Provisional Patent Application Ser. No. 60/985,142, filed Nov. 2, 2007 entitled “Dual Locking General Purpose Clip and Method of Forming the Same,” the entire disclosure of which is incorporated by reference herein. This patent application is related to U.S. Pat. No. 5,123,456 issued Jun. 23, 1992, entitled “Banding Tool Including Clamping Plunger” and U.S. Pat. No. 6,481,467 issued Nov. 19, 2002, entitled “Powered Band Clamping Under Electrical Control,” both being incorporated by reference in their entirety herein.
Number | Date | Country | |
---|---|---|---|
61035999 | Mar 2008 | US | |
60985142 | Nov 2007 | US |