Patent Application
20070246586
1. Field of the Invention
The present invention relates to shredders for destroying articles, such as documents, compact discs, etc.
2. Description of Related Art
Shredders are well known devices for destroying articles, such as documents, compact discs (“CDs”), expired credit cards, etc. Typically, users purchase shredders to destroy sensitive articles, such as credit card statements with account information, documents containing company trade secrets, etc.
A common type of shredder has a shredder mechanism contained within a housing that is removably mounted atop a container. The shredder mechanism typically has a series of cutter elements that shred articles fed therein and discharge the shredded articles downwardly into the container. The shredder typically has a stated capacity, such as the number of sheets of paper (typically of 20 lb. weight) that may be shredded at one time; however, the feed throat of a typical shredder can receive more sheets of paper than the stated capacity. A common frustration of users of shredders is to feed too many papers into the feed throat, only to have the shredder jam after it has started to shred the papers. To free the shredder of the papers, the user typically reverses the direction of rotation of the cutter elements via-a switch until the papers become free.
In addition, shredders-that are subjected to a lot of use should have periodic maintenance done to them. For example, the cutter elements may become dull over time. It has been found that lubricating the cutter elements may improve the performance of cutter elements, particularly if the shredder is used constantly over a long period of time.
The present invention endeavors to provide various improvements over known shredders.
It is an aspect of the invention to provide a shredder that does not jam as a result of too many papers, or an article that is too thick, being fed into the shredder.
In an embodiment, a shredder is provided. The shredder includes a housing having a throat for receiving at least one article to be shredded, and a shredder mechanism received in the housing. The shredder mechanism includes an electrically powered motor and cutter elements. The shredder mechanism enables the at least one article to be shredded to be fed into the cutter elements. The motor is operable to drive the cutter elements so that the cutter elements shred the articles fed therein. The shredder also includes a detector that is configured to detect a thickness of the at least one article being received by the throat, and a controller that is operable to perform a predetermined operation responsive to the detector detecting that the thickness of the at least one article is at least equal to a predetermined maximum thickness.
In an embodiment, a method for operating a shredder is provided. The method includes detecting a thickness of at least one article being inserted into a throat of the shredder, determining if the thickness of the at least one article is greater than a predetermined maximum thickness, and performing a predetermined operation if the detected thickness is at least equal to the predetermined maximum thickness.
It is also an aspect of the present invention to provide a shredder that automatically conducts self-maintenance after a predetermined amount of use.
In an embodiment, a shredder that includes a housing that has a throat for receiving at least one article to be shredded, and a shredder mechanism that is received in the housing is provided. The shredder mechanism includes an electrically powered motor and cutter elements. The shredder mechanism enables the at least one article to be shredded to be fed into the cutter elements and the motor being operable to drive the cutter elements so that the cutter elements shred the articles fed therein. The shredder also includes a lubrication system configured to lubricate the cutter elements, and a detector configured to detect a thickness of the at least one article being received by the throat. The shredder farther includes a controller that is operable to store an accumulation of thicknesses detected by the detector over time and to provide a signal to the lubrication system to lubricate the cutter elements when the accumulation is at least equal to a predetermined total thickness.
In an embodiment, a shredder is provided. The shredder includes a housing having a throat for receiving at least one article to be shredded, and a shredder mechanism that is received in the housing. The shredder mechanism includes an electrically powered motor and cutter elements. The shredder mechanism enables the at least one article to be shredded to be fed into the cutter elements. The motor is operable to drive the cutter elements so that the cutter elements shred the articles fed therein. The shredder also includes a controller that includes a memory. The controller is operable to store information in the memory related to an amount of use of the shredder, and to alert a user of the shredder when the shredder is due for a maintenance operation, based on the amount of use of the shredder.
Other aspects, features, and advantages of the present invention will become apparent from the following detailed description, the accompanying drawings, and the appended claims.
As shown in
The shredder 10 also includes the shredder housing 14, mentioned above. The shredder housing 14 includes top wall 24 that sits atop the container 12. The top wall 24 is molded from plastic and an opening 26 is located at a front portion thereof. The opening 26 is formed in part by a downwardly depending generally U-shaped member 28. The U-shaped member 28 has a pair of spaced apart connector portions 27 on opposing sides thereof and a hand grip portion 28 extending between the connector portions 27 in spaced apart relation from the housing 14. The opening 26 allows waste to be discarded into the container 12 without being passed through the shredder mechanism 16, and the member 28 may act as a handle for carrying the shredder 10 separate from the container 12. As an optional feature, this opening 26 may be provided with a lid, such as a pivoting lid, that opens and closes the opening 26. However, this opening in general is optional and may be omitted entirely. Moreover, the shredder housing 14 and its top wall 24 may have any suitable construction or configuration.
The shredder housing 14 also includes a bottom receptacle 30 having a bottom wall, four side walls and an open top. The shredder mechanism 16 is received therein, and the receptacle 30 is affixed to the underside of the top wall 24 by fasteners. The receptacle 30 has an opening 32 in its bottom wall through which the shredder mechanism 16 discharges shredded articles into the container 12.
The top wall 24 has a generally laterally extending opening, which is often referred to as a throat 36, extending generally parallel and above the cutter elements. The throat 36 enables the articles being shredded to be fed into the cutter elements. As can be appreciated, the throat 36 is relatively narrow, which is desirable for preventing overly thick items, such as large stacks of documents, from being fed into cutter elements, which could lead to jamming. The throat 36 may have any configuration.
The top wall 24 also has a switch recess 38 with an opening therethrough. An on/off switch 42 includes a switch module (not shown) mounted to the top wall 24 underneath the recess 38 by fasteners, and a manually engageable portion 46 that moves laterally within the recess 38. The switch module has a movable element (not shown) that connects to the manually engageable portion 46 through the opening. This enables movement of the manually engageable portion 46 to move the switch module between its states.
In the illustrated embodiment, the switch module connects the motor 18 to the power supply. Typically, the power supply will be a standard power cord 44 with a plug 48 on its end that plugs into a standard AC outlet. The switch 42 is movable between an on position and an off position by moving the portion 46 laterally within the recess 38. In the on position, contacts in the switch module are closed by movement of the manually engageable portion 46 and the movable element to enable a delivery of electrical power to the motor 18. In the off position, contacts in the switch module are opened to disable the delivery of electric power to the motor 18.
As an option, the switch 42 may also have a reverse position wherein contacts are closed to enable delivery of electrical power to operate the motor 18 in a reverse manner. This would be done by using a reversible motor and applying a current that is of a reverse polarity relative to the on position. The capability to operate the motor 18 in a reversing manner is desirable to move the cutter elements in a reversing direction for clearing jams. In the illustrated embodiment, in the off position the manually engageable portion 46 and the movable element would be located generally in the center of the recess 38, and the on and reverse positions would be on opposing lateral sides of the off position.
Generally, the construction and operation of the switch 42 for controlling the motor 42 are well known and any construction for such a switch 42 may be used.
In the illustrated embodiment, the top cover 24 also includes another recess 50 associated with an optional switch lock 52. The switch lock 52 includes a manually engageable portion 54 that is movable by a user's hand and a locking portion (not shown). The manually engageable portion 54 is seated in the recess 50 and the locking portion is located beneath the top wall 24. The locking portion is integrally formed as a plastic piece with the manually engageable portion 54 and extends beneath the top wall 24 via an opening formed in the recess 50.
The switch lock 52 causes the switch 42 to move from either its on position or reverse position to its off position by a camming action as the switch lock 52 is moved from a releasing position to a locking position. In the releasing position, the locking portion is disengaged from the movable element of the switch 42, thus enabling the switch 42 to be moved between its on, off, and reverse positions. In the locking position, the movable element of the switch 42 is restrained in its off position against movement to either its on or reverse position by the locking portion of the switch lock 52.
Preferably, but not necessarily, the manually engageable portion 54 of the switch lock 52 has an upwardly extending projection 56 for facilitating movement of the switch lock 52 between the locking and releasing positions.
One advantage of the switch lock 52 is that, by holding the switch 42 in the off position, to activate the shredder mechanism 16 the switch lock 52 must first be moved to its releasing position, and then the switch 42 is moved to its on or reverse position. This reduces the likelihood of the shredder mechanism 16 being activated unintentionally. Reference may be made to U.S. Patent Application Publication No. 2005-0218250 A1, which is incorporated herein by reference, for further details of the switch lock 52. This switch lock is an entirely optional feature and may be omitted.
In the illustrated embodiment, the shredder housing 14 is designed specifically for use with the container 12 and it is intended to sell them together. The upper peripheral edge 60 of the container 12 defines an upwardly facing opening 62, and provides a seat 61 on which the shredder 10 is removably mounted. The seat 61 includes a pair of pivot guides 64 provided on opposing lateral sides thereof. The pivot guides 64 include upwardly facing recesses 66 that are defined by walls extending laterally outwardly from the upper edge 60 of the container 12. The walls defining the recesses 66 are molded integrally from plastic with the container 12, but may be provided as separate structures and formed from any other material. At the bottom of each recess 66 is provided a step down or ledge providing a generally vertical engagement surface 68. This step down or ledge is created by two sections of the recesses 66 being provided with different radii. Reference may be made to U.S. Pat. No. 7,025,293, which is incorporated herein by reference, for further details of the pivotal mounting. This pivotal mounting is entirely optional and may be omitted.
As schematically illustrated in
The pump 82 communicates through a series of conduits 88 to one or more nozzles 90 that are positioned proximate the cutter elements 19. In one embodiment, the nozzles can be positioned such that oil forced through the nozzles is dispersed as sprayed droplets in the throat of the shredder 10. In another embodiment, the oil is dispersed in back of the throat of the shredder 10. Generally, the nozzles have openings small relative to the conduits, thereby creating a high speed flow at the nozzle, allowing the oil to be expelled at a predictable rate and pattern.
As shown in
An alternate embodiment includes the system 80 built into the housing of the shredder 10. In this embodiment, shown in
In operation, a controller 96 (shown in
In an embodiment of the invention, the shredder 10 includes a thickness detector 100 to detect overly thick stacks of documents or other articles that could jam the shredder mechanism 16, and communicate such detection to a controller 200, as shown in
A visual signal may be provided in the form of a red warning light, which may be emitted from an LED. It is also contemplated that a green light may also be provided to indicate that the shredder 10 is ready to operate. In an embodiment, the indicator 110 is a progressive indication system that includes a series of indicators in the form of lights to indicate the thickness of the stack of documents or other article relative to the capacity of the shredder is provided, as illustrated in
The sequence of lights may be varied and their usage may vary. For example, they may be arranged linearly in a sequence as shown, or in other configurations (e.g. in a partial circle so that they appear like a fuel gauge or speedometer. Also, for example, the yellow light(s) 114 may be lit only for thickness(es) close to (i.e., within 25% of) the predetermined maximum thickness, which triggers the red light 116. This is a useful sequence because of most people's familiarity with traffic lights. Likewise, a plurality of green lights (or any other color) could be used to progressively indicate the detected thickness within a range. Each light would be activated upon the detected thickness being equal to or greater than a corresponding predetermined thickness. A red (or other color) light may be used at the end of the sequence of lights to emphasize that the predetermined maximum thickness has been reached or exceeded (or other ways of getting the user's attention may be used, such as emitting an audible signal, flashing all of the lights in the sequence, etc.). These alert features may be used in lieu of or in conjunction with cutting off power to the shredder mechanism upon detecting that the predetermined maximum thickness has been reached or exceeded.
Similarly, the aforementioned indicators of the progressive indicator system may be in the form of audible signals, rather than visual signals or lights. For example, like the yellow lights described above, audible signals may be used to provide a progressive indication of the thickness of the item. The audible signals may vary by number, frequency, pitch, and/or volume in such a way that provides the user with an indication of how close the detected thickness of the article is to the predetermined maximum thickness. For example, no signal or a single “beep” may be provided when the detected thickness is well below the predetermined maximum thickness, and a series of “beeps” that increase in number (e.g. more “beeps” the closer the detection is to the predetermined maximum thickness) and/or frequency (e.g. less time between beeps the closer the detection is to the predetermined maximum thickness) as the detected thickness approaches the predetermined maximum thickness may be provided. If the detected thickness is equal to or exceeds the predetermined maximum thickness, the series of “beeps” may be continuous, thereby indicating to the user that such a threshold has been met and that the thickness of the article to be shredded should be reduced.
The visual and audible signals may be used together in a single device. Also, other ways of indicating progressive thicknesses of the items inserted in the throat 36 may be used. For example, an LCD screen with a bar graph that increases as the detected thickness increases may be used. Also, a “fuel gauge,” i.e., a dial with a pivoting needle moving progressively between zero and a maximum desired thickness, may also be used. As discussed above, with an audible signal, the number or frequency of the intermittent audible noises may increase along with the detected thickness. The invention is not limited to the indicators described herein, and other progressive (i.e., corresponding to multiple predetermined thickness levels) or binary (i.e., corresponding to a single predetermined thickness) indicators may be used.
The aforementioned predetermined thicknesses may be determined as follows. First, because the actual maximum thickness that the shredder mechanism may handle will depend on the material that makes up the item to be shredded, the maximum thickness may correspond to the thickness of the toughest article expected to be inserted into the shredder, such as a compact disc, which is made from polycarbonate. If it is known that the shredder mechanism may only be able to handle one compact disc at a time, the predetermined maximum thickness may be set to the standard thickness of a compact disc (i.e., 1.2 mm). It is estimated that such a thickness would also correspond to about 12 sheets of 20 lb. paper. Second, a margin for error may also be factored in. For example in the example given, the predetermined maximum thickness may be set to a higher thickness, such as to 1.5 mm, which would allow for approximately an additional 3 sheets of paper to be safely inserted into the shredder (but not an additional compact disc). Of course, these examples are not intended to be limiting in any way.
For shredders that include separate throats for receiving sheets of paper and compact discs and/or credit cards, a detector 100 may be provided to each of the throats and configured for different predetermined maximum thicknesses. For example, the same shredder mechanism may be able to handle one compact disc and 18 sheets of 20 lb. paper. Accordingly, the predetermined maximum thickness associated with the detector associated with the throat that is specifically designed to receive compact discs may be set to about 1.5 mm (0.3 mm above the standard thickness of a compact disc), while the predetermined maximum thickness associated with the detector associated with the throat that is specifically designed to receive sheets of paper may be set to about 1.8 mm. Of course, these examples are not intended to be limiting in any way and are only given to illustrate features of embodiments of the invention.
Similarly, a selector switch may optionally be provided on the shredder to allow the user to indicate what type of material is about to be shredded, and, hence the appropriate predetermined maximum thickness for the detector. A given shredder mechanism may be able to handle different maximum thicknesses for different types of materials, and the use of this selector switch allows the controller to use a different predetermined thickness for the material selected. For example, there may be a setting for “paper,” “compact discs,” and/or “credit cards,” as these materials are known to have different cutting characteristics and are popular items to shred for security reasons. Again, based on the capacity of the shredder mechanism, the appropriate predetermined maximum thicknesses may be set based on the known thicknesses of the items to be shredded, whether it is the thickness of a single compact disc or credit card, or the thickness of a predetermined number of sheets of paper of a known weight, such as 20 lb. The selector switch is an optional feature, and the description thereof should not be considered to be limiting in any way.
Returning to
In another embodiment, illustrated in
In another embodiment, illustrated in
Another embodiment of the detector 100 that includes the optical sensor 140 is shown in
Although various illustrated embodiments herein employ particular sensors, it is to be noted that other approaches may be employed to detect the thickness of the stack of documents or article being fed into the throat 36 of the shredder 10. For example, embodiments utilizing eddy current, inductive, photoelectric, ultrasonic, Hall effect, or even infrared proximity sensor technologies are also contemplated and are considered to be within the scope of the present invention.
The sensors discussed above, and other possible sensors, may also be used to initiate the shredding operation by enabling the power to be delivered to the motor of the shredder mechanism. This use of sensors in the shredder throat is known, and they allow the shredder to remain idle until an item is inserted therein and contacts the sensor, which in turn enables power to operate the motor to rotate the cutting elements via the shafts. The controller 200 may be configured such that the insertion of an item will perform this function of enabling power delivery to operate the shredder mechanism motor. The motor may be cut-off or not even started if the thickness exceeds the predetermined maximum thickness.
Returning to
It is also possible to schedule the lubrication based on a number of uses of the shredder (e.g., the controller tracks or counts the number of shredding operations and activates the pump after a predetermined number of shredder operations). In each of the embodiments making use of accumulated measures, a memory 97 can be incorporated for the purpose of tracking use. Although the memory 97 is illustrated as being part of the controller 96 associated with the lubrication system, the memory may be part of the shredder controller 200, or may be located on some other part of the shredder 10. The illustrated embodiment is not intended to be limiting in any way.
In addition, the accumulated measures (e.g. the number of shredding operations or the accumulated thickness of the articles that have been shredded) may be used to alert the user that maintenance should be completed on the shredder. The alert may come in the form of a visual or audible signal, such as the signals discussed above, or the controller may prevent power from powering the shedder mechanism until the maintenance has been completed.
The ability to keep track of the accumulated use of the shredder may also be helpful in a warranty context, where the warranty could be based on the actual use of the shredder, rather than time. This is similar to the warranties that are used with automobiles, such as “100,000 miles or 10 years, whichever comes first.” For example, the warranty may be based on 100 uses or one year, whichever comes first, or the warranty may be based on shredding paper having a total sensed thickness of 1 meter or 2 years, whichever comes first, and so on.
If the controller 200 determines that the thickness that has been detected is less than the predetermined maximum thickness, the controller 200 may cause the green light 112 to illuminate and/or allows power to be supplied to the shredder mechanism 16 so that the shredder 10 may proceed with shredding the item at 316.
In the embodiment that includes the plurality of yellow lights 114 as part of the indicator 100, if the controller 200 determines that the thickness that has been detected is less than the predetermined maximum thickness, but close to or about the predetermined maximum thickness, the controller 200 may cause one of the yellow lights to illuminate, depending on how close to the predetermined maximum thickness the detected thickness is. For example, the different yellow lights may represent increments of about 0.1 mm so that if the detected thickness is within 0.1 mm of the predetermined maximum thickness, the yellow light 114 that is closest to the red light 116 illuminates, and so on. Although power will still be supplied to the shredder mechanism 16, the user will be warned that that particular thickness is very close to the capacity limit of the shredder 10. Of course, any increment of thickness may be used to cause a particular yellow light to illuminate. The example given should not be considered to be limiting in any way.
Returning to the method 300 of
The foregoing illustrated embodiments have been provided to illustrate the structural and functional principles of the present invention and are not intended to be limiting. To the contrary, the present invention is intended to encompass all modifications, alterations and substitutions within the spirit and scope of the appended claims.
This application is a divisional application of U.S. patent application Ser. No. 11/444,491, filed Jun. 1, 2006, which is a continuation-in-part of U.S. patent application Ser. No. 11/177,480, filed Jul. 11, 2005, which in turn is a continuation-in-part of U.S. patent application Ser. No. 10/937,304, filed on Sep. 10, 2004, the entire contents of which are all incorporated herein by reference. This application is also a continuation-in-part of U.S. patent application Ser. No. 11/385,864, filed on Mar. 22, 2006, the entire content of which is also incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 11444491 | Jun 2006 | US |
| Child | 11770223 | Jun 2007 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 11177480 | Jul 2005 | US |
| Child | 11444491 | Jun 2006 | US |
| Parent | 10937304 | Sep 2004 | US |
| Child | 11177480 | Jul 2005 | US |
| Parent | 11385864 | Mar 2006 | US |
| Child | 11770223 | Jun 2007 | US |
