Patent Grant
8882011
1. Field of Invention
The present invention is generally related to an apparatus having cutter elements disposed on a shaft for destroying a plurality of articles such as paper and discs. In particular, the apparatus comprises an oiling mechanism associated with the shaft for lubricating the cutter elements located thereon.
2. Background
Shredders are well known devices for destroying substrate articles, such as documents, CDs, floppy disks, etc. Typically, users purchase shredders to destroy sensitive articles, such as credit card statements with account information, documents containing company trade secrets, etc.
Typically, a shredder has a shredder mechanism contained within a housing, and the housing has a feed opening enabling substrates to be fed into the shredder mechanism. As with other mechanical devices, wear may be reduced and performance may be maintained by proper lubrication of moving parts. In particular, wear on cutting blades of the shredder mechanism and load on the shredder motor can be reduced by oiling the cutting blades.
In one approach, shredders have relied on lubrication systems having a plurality of nozzles that communicate with a reservoir of oil for spraying the oil directly onto the cutting blades. The plurality of spray nozzles can also optionally spray the oil onto an intermediate surface that enables the oil to flow onto the cutting blades. Examples of such approach are described in U.S. Pat. No. 7,798,435.
In other approaches, the lubrication system for lubricating shredders may include a manifold or openings that enable oil to drip onto the cutting blades. However, these approaches do not direct the oil to the cutting blades at a predictable rate or pattern. Accordingly, these approaches result in inefficiency and waste because some of the oil that drips from the manifold do not eventually drop onto areas of the cutting blades that require lubrication. Examples of such approaches are described in U.S. Pat. Nos. 5,494,229 and 5,186,398.
One aspect of the invention provides a shredder for shredding substrates, having a housing and a substrate receiving opening provided on the housing. The shredder also includes a shredder mechanism received in the housing and comprising a motor, a pair of cooperating shredding structures each having a set of spaced apart cutter elements interleaving with one another such that substrates fed through the substrate receiving opening are fed between the interleaved sets of cutter elements. At least one of the cooperating shredding structures includes a rotatably mounted shaft rotatable by the motor with its cutter elements mounted in spaced apart relation with spaces therebetween. The shredder mechanism enables substrates to be shredded to be fed between the interleaved sets of cutter elements and the motor is operable to rotate the shaft in a shredding direction so that the cutter elements shred the substrates fed therein. The shaft has a tubular body with an inner surface defining a hollow interior, an outer surface, and a plurality of openings formed through the tubular body open to the inner and outer surfaces, the openings that are open to the spaces between the cutter elements on the shafts. The shredder further includes a supply of lubricant communicating with the plurality of openings of the shaft so as to deliver the lubricant from the interior of the shaft to the cutter elements through the openings.
A preferred aspect of the invention provides each of the cooperating shredding structures with a rotatably mounted shaft each rotatable by the motor with its cutter elements mounted in spaced apart relations with spaces therebetween. The motor is operable to rotate each shaft in a shredding direction so that the cutter elements shred the substrates therebetween. Each shaft has a tubular body with an inner surface defining a hollow interior, an outer surface, and a plurality of openings formed through the tubular body open to the inner and outer surfaces. The openings are open to the spaces between the cutter elements on each shaft. The supply of lubricant communicates with the plurality of openings of the shaft so as to deliver the lubricant from the interior of each shaft to the cutter elements through the openings.
Other objects, features, and advantages of the present invention will become apparent from the following detailed description, the accompanying drawings, and the appended claims.
In some embodiments, a separate receiving path and throat may be provided to shred compact discs (CDs) or other materials. In the illustrated embodiment only one motor is shown; however, the drive system may have any number of motors. A plurality of the cutter elements 25, 27 are mounted on first and second rotatable shafts 20 and 22 in any suitable manner, and an exemplary embodiment of the shafts 20 and 22 with the cutter elements 25, 27 is illustrated in
Generally speaking, shredder 10 may have any suitable construction or configuration and the illustrated embodiment is not intended to be limiting in any way. For example, the present invention may be incorporated into Model C-425Ci Powershred 0 shredders available from Fellowes, Inc., of Itasca, Ill., or any other type of shredder. In addition, the term “shredder” is not intended to be limited to devices that literally “shred” documents and articles, but is instead intended to cover any device that destroys documents and articles in a manner that leaves each document or article illegible and/or useless. For example, the lubrication system 50 may be used in disintegrators, or other devices.
The shredder 10 includes the shredder housing 41, mentioned above. The shredder housing 41 includes a top cover 11, and a bottom receptacle 14. It is contemplated that in some embodiments, the sub-frame 21 may serve as a bottom receptacle and a separate bottom receptacle 14 may be omitted. In this embodiment, the shredder housing 41 includes the top cover or wall 11 that sits atop the upper periphery of the bottom receptacle 14. The top cover or wall 11 is molded from a plastic material or any other material. The shredder housing 41 and its top wall or cover 11 may have any suitable construction or configuration. The top cover or wall 11 has an opening, which is often referred to as the throat 38, extending generally parallel and above the cutter elements. The throat 38 enables the articles being shredded to be fed into the cutter elements.
The shredder 10 includes the bottom receptacle 14 having a bottom wall, four side walls and an open top. The bottom receptacle 14 is molded from a plastic material or any other material. The bottom receptacle 14 sits atop the upper periphery of the bottom housing 16 in a nested relation using flange portions of the bottom receptacle 14 that generally extend outwardly from the side walls thereof. In embodiments where the separate bottom receptacle is eliminated, the shredder mechanism 17 may directly sit atop the upper periphery of the bottom housing 16. In the embodiment shown in
In the illustrated embodiment, the shredder 10 sits atop the large freestanding housing 16, which is formed of molded plastic material or any other material. The housing 16 includes a bottom wall, three side walls, an open front and an open top. The side walls of the container 16 provide a seat on which the shredder housing 41 is removably mounted. The housing 16 is constructed and arranged to receive the waste container 15 therein. In other words, the waste container 15 is enclosed in the housing 16. The waste container 15 is formed of molded plastic material or any other material. The waste container 15 is in the form of a pull-out bin that is constructed and arranged to slide in and out of the housing 16 through an opening in the front side thereof. The waste container 15 is configured to be removably received within the housing 16. The waste container 15 includes a bottom wall, four side walls, and an open top. The waste container 15 includes a handle 19 that is configured to allow a user to grasp and pull out the waste container 15 from the housing 16. In the illustrated embodiment, the handle 19 is located on the front, side wall of the waste container 15. Any construction or configuration for the housing or waste container may be used, and the illustrated embodiment is not limiting. The shredder 10 may optionally be provided with roller members 24, such as wheels or casters, that facilitate the transport of the shredder 10 from one place to another
The cover 11 may include a switch recess with an opening therethrough. An on/off switch that includes a switch module may be mounted to the top cover 11 underneath the switch recess by fasteners, and a manually engageable portion that moves laterally within the switch recess. The switch module has a movable element that connects to the manually engageable portion through the opening. This enables movement of the manually engageable portion to move the switch module between its states.
The switch module is configured to connect the motor 13 to the power supply. This connection may be direct or indirect, such as via a controller. Typically, the power supply will be a standard power cord with a plug on its end that plugs into a standard AC outlet. The switch is movable between an on position and an off position by moving the manually engageable portion laterally within the switch recess. As an option, the switch may also have a reverse position wherein contacts are closed to enable delivery of electrical power to operate the motor 13 in a reverse manner. The capability to operate the motor 13 in a reverse manner is desirable to move the cutter elements in a reversing direction for clearing jams.
The detector 43 may be activation sensors that are activated when the sensors detect articles that are inserted into the throat 38. When the switch is in its on (or idle) position, the controller may be configured to operate the motor 13 to drive the cutter elements 25, 27 of the shredder mechanism 17 in the shredding direction when the detector 43 detects the presence or insertion of the articles to be shredded. Having the detectors 43 activate the shredder 10 is desirable because it allows the user to ready the shredder 10 by moving the switch to its on position, but the controller will not operate the shredder mechanism 17 to commence shredding until the sensors detect the presence or insertion of one or more articles in the throat 38. Once the articles have passed into the shredder mechanism 17 beyond the detector 43, the controller will then stop the movement or rotation of the cutter elements 25, 27 of shredding mechanism 20, as that corresponds to the articles having been fully fed and shredded. The use of such sensors to activate the shredder mechanism 20 is beneficial because it allows the user to perform multiple shredding tasks without having the shredder mechanism 20 operating, making noise, between tasks. It also reduces wear on the shredder mechanism 20, as it will only operate when substrates are fed therein, and will not continually operate. In some embodiments, the detector 43 may also be a thickness detector configured to detect thickness of the articles inserted into the throat 38.
As shown in
In some embodiments, the first and second rotatable shafts 20 and 22 are designed to be coupled to the drive system 28 (e.g., motor 13) such that the shafts are counter-driven in respective, opposite rotational cutting directions. First rotatable shaft 20 may be rotated in a clockwise direction and second rotatable shaft 22 may be rotated in a counter-clockwise direction, such that the cutter elements 25 of first rotatable shaft 20 interleave with the cutter elements on second rotatable shaft 22. When articles are inserted into the throat 38 and into path 60, shafts 20, 22 are positioned to be rotationally counter-driven by motor 13 in a rotational cutting direction, and the article is fed between first and second rotating shafts 20 and 22 and their corresponding cutter elements 25 and 27. As the cutter elements 25 and 27 interleave with each other, they are configured to cooperate to shred the articles fed therebetween through the throat 38, and drive such down through paper path 60 defined between the shafts 20, 22.
The shredder mechanism 17 may also include strippers 62, 64 that correspond with first and second shafts 20, 22, respectively. Rods 58, 59 may be located above the shafts 20, 22 and the strippers 62, 64. In one embodiment, each set of strippers 62, 64 has an array of engaging members with spaces therebetween to receive portions of the cutter elements 25, 27 such that the cutter elements 25, 27 are interleaved with the engaging members of the strippers 62, 64. The strippers 62, 64 may be provided to strip away the shredded article as it is fed through the interleaving cutter elements 25 and 27. That is, the strippers 62, 64 may prevent the cut article from winding up on the shafts during rotation. This prevents clogging of the cutting area and the shredder mechanism 17 from jamming. As shown in
In some embodiments, the shredder may be provided with a stationary structure 102 (see
As shown in
The pump 78 may be operatively connected to the controller, which may be programmed with instructions for determining when to lubricate the cutter elements 25, 27. The term “controller” may be used to refer to any device that controls operation of a component of the shredder 10. For example, a controller may be a device or microcontroller having a central processing unit (CPU) and input/output devices that are used to monitor parameters from devices that are operatively coupled to the controller. The input/output devices also permit the CPU to communicate and control the devices (e.g., such as a sensor or the motor 13) that are operatively coupled to the controller. As is generally known in the art, the controller may optionally include any number of storage media such as memory or storage for monitoring or controlling the sensors coupled to the controller. In some embodiments, a controller may be a conventional circuit with no processor, and may comprise one or more binary switches or a relays. The controller may optionally comprise a processor. In some embodiments, the controller may be circuitry configured to activate or operate components of the shredder 10 in accordance with logic, rules, and/or software. In an embodiment, the controller may process the instructions and subsequently apply them by activating the pump 78. The pump 78 may be activated at certain times or intervals, at user selected times, or may be continuously activated. The controller may be programmed to operate the pump 78 in a number of different modes. In one embodiment, the controller is programmed to operate according to a predetermined timing schedule. In another, the controller activates the pump 78 upon a certain number of rotations of the drive for the cutter elements 25, 27. In another embodiment, the detector 43 monitors a thickness of items deposited into the throat 38. Upon accumulation of a predetermined total thickness of material shredded, the controller activates the pump 78 to lubricate the cutter elements 25, 27. It is also possible to schedule the lubrication based on a number of uses of the shredder 10 (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 can be incorporated for the purpose of tracking use. In each foregoing embodiment, the shredder 10 may include a manual control to allow a user to operate the system outside of the schedule determined by the controller. The shredder 10 can include any of these and other features described in U.S. Pat. No. 7,798,435, which is incorporated herein in its entirety.
As shown in
In some embodiments, the shafts 20, 22 may function as lubricant distribution manifolds. In the embodiment shown in
During manufacture, the shaft 20 may be expanded from a consistent external diameter to achieve the configuration and arrangement described above. The shaft 20 may be expanded outward against and around the inner surfaces of the cutter elements 25, as is shown in U.S. Pat. No. 5,799,887, the entirety of which is incorporated herein by reference. In some embodiments, the inner surfaces of the cutter elements 25 may be provided with teeth or other structures that enable the cutter elements 25 to grip or lock onto the shaft 20 after the shaft 20 has been expanded. The shaft 20 may be expanded in a number of different ways. For example, the shaft 20 is expanded by pumping a hydraulic fluid such as water through the shaft with a high amount of pressure. The amount of pressure used depends on the size, thickness, and material of the shaft being expanded. As an illustrative example, water may be pumped through a 0.5 inch steel shaft having a 0.035 inch thick wall at a pressure of about 18,000 pounds per square inch.
The shaft 20 may also be expanded by driving a mandrel or a ball bearing through the shaft 20. The mandrel and ball bearing would have an outer diameter greater than the inner diameter of the shaft 20, but smaller than the inner diameter of the cutter elements 25. As a result, the mandrel or ball bearing would expand the shaft outward against and around the inner surfaces of the cutter elements 25 as the mandrel or ball bearing passes through the hollow shaft 20. The mandrel or ball bearing could be driven through the hollow shaft 20 by hydraulic, pneumatic, or explosive pressure, mechanical jacking, or any other suitable means that can apply the requisite force. After expanding the shaft, the mandrel, or a portion thereof, may also be left inside the hollow shaft 20 to provide extra support for the shaft 20.
As a result of the expansion, the outer surface of the shaft 20 lines the inner surface of the cutter elements 25 so that cutter elements 25 are fixed from substantial rotation about the expanded shaft 20 as well as from substantial lateral movement along the expanded shaft 20. Accordingly, once the shaft 20 is expanded, it becomes the shaft 20 described above with the first and second alternating outer surface portions 86, 88.
The shaft 20 may have a circular cross-section, although it is conceivable that the shaft could have a cross-section with a variety of different geometric configurations. Additionally, the shaft 20 may be made out of any desirable material, such as aluminum, steel, or plastic, that has good strength and ductility. The shaft may be made out of steel that is relatively softer than the material used for the cutter discs. As a result, the shaft will expand under applied force or pressure before the cutter discs. It is also contemplated that a driving gear (not shown) may be fixed to the shaft 20 in a similar manner as the cutter elements 25. Alternatively, the driving gear may be separately attached thereon.
In some embodiments, the shaft 20 may be a porous metal tube that is constructed by isostatically pressing powdered metal in molds, thus resulting in a seamless tube structure. The tube structure may then be sintered to form a rigid porous filter tube that may be used as a lubricant distribution manifold.
The configuration and arrangement of the second shaft 22 may be similar to the first shaft 20 described above. The second shaft 22 may also be made in a similar manner.
As shown in
As shown in
The filler material 92 is a lubricant permeable material. It may be open cell foam, such as, just for example, open cell polyurethane foam. The filler material 92 may also be fillers, such as pellets, sand, porous materials, or any other material that allows the lubricant to permeate therethrough and delays the release of the lubricant through the openings 90. In such embodiments, the lubricant may saturate the filler material 92 before the lubricant can exit the openings 90 to lubricate the cutter elements 25. Thus, the filler materials 92 can be disposed in the hollow space 81 of the shaft 20 for slow and even lubricant delivery. The type of material used as the filler material 92 may affect the rate at which lubricant seeps from the delivery tube 100 to the openings 90, and thus the type of material used as filler material 92 may be dependent on the desired rate of release of the lubricant.
The arrangement of the openings 90 and the use of the filler materials 92 enable lubricant to be delivered to areas requiring the most lubrication efficiently such that less lubricant is required to effectively lubricate the cutter elements 25, 27. For example, these areas may include the portions of the cutter elements 25, 27 that contact the articles to be shredded more often than other portions of the cutter elements 25, 27, such that they are subject to constant wear. In some embodiments, the shafts 20, 22 may be constructed and arranged to function similarly as a “soaker hose.” That is, openings 90 may be provided along the shaft 20 such that the lubricant may seep or drip from the openings 90 in the shafts 20, 22 to reach the cutter elements 25, 27. This may efficiently and effectively lubricate the cutter elements 25, 27 while minimizing waste of lubricant. As mentioned above, the openings 90 may be provided in a helical pattern along the shaft 20, as shown in
The lubrication used by the lubrication system 50 can be solid or fluid (liquid). In some embodiments, the solid lubricants can be placed inside the hollow space 81 of the shafts 20, 22. For example, in one embodiment, a disposable cardboard cartridge holding a solid lubricant can be placed in the hollow space 81 of the shaft 20. In some embodiments, the disposable cardboard cartridge may be used to facilitate the insertion of the solid lubricant into the hollow space 81 of the shaft 20 and then withdrawn from the shaft 20 after the lubricant has been inserted therein. In some embodiments, the disposable cardboard cartridge may be provided with openings that enable the solid lubricant to flow radially outwards therefrom towards the openings 90 of the shaft 20 after the solid lubricant has been heated. The solid lubricant may be vegetable shortening or grease. Alternatively, paraffin or other types of lubricants may be used. In some embodiments, the cartridge may be similar to the grease cartridges known in the art that are used with grease-injector guns. Examples of these cartridges include, but not are not limited to, Lubriplate® Grease Cartridges, Mobil® 1 Synthetic Universal Grease Cartridge, and others. The supply of lubricant can be a reservoir of lubricant or a source of lubricant external to the shafts 20, 22 or the supply of lubricant can be a reservoir of lubricant or a source of lubricant in the interior space 81 of the shafts 20, 22. For example, in embodiments using liquid lubricant, the reservoir 70 may hold a first supply of lubricant, and the interior of the shaft may also hold a second supply of lubricant after the lubricant has been delivered to the shafts 20, 22 from the reservoir 70.
In embodiments using solid lubricants, the solid lubricant can be formulated to melt at a specific temperature (e.g., 60° C. to 70° C. or any other temperatures). Accordingly, the solid lubricant may melt when the shredder 10 is in operation. For example, heat generated by operation of the motor may melt the lubricant. In addition, friction between the strippers 62, 64 and the cutter elements 25, 27 may also melt the lubricant. In such situations, pro-longed or constant operation of the shredder 10 may result in increased friction, which generates more heat. This increased heat may melt the solid lubricant and result in a coating of oil on the cutting shafts 20, 22. The coating of oil may reduce friction, and the heat from the friction may be reduced as a result. This reduction in heat then results in less solid lubricant being melted. However, the amount of solid lubricant being melted may increase again after friction is increased due to prolonged or constant use of the shredder 10. Accordingly, the amount of friction may determine the amount of solid lubricant being melted. Thus, in some embodiments, the solid lubricant may melt when the shredder 10 has been heavily used (i.e., near the end of a duty cycle) and the heat generated by the shredder 10 may cause the solid lubricant to melt to lubricate the cutter elements 25, 27. Alternatively or additionally, an external heat element or source (not shown) may be used with the lubrication system 50 to release the lubricant on demand For example, in one embodiment, resistive heaters may be placed inside the shafts 20, 22 to heat the lubricants. Alternatively, the heat element may be placed in close proximity to the cutting shafts 20, 22. In some embodiments, the external heat source may apply sufficient heat at certain time intervals, random times, or user selected times, to melt the solid lubricant to lubricate the cutter elements 25, 27. In embodiments where the disposable cardboard cartridges are used, the pump 78 and the conduits 80a, 80b may be optional. However, it is contemplated that the lubrication system 50 may include any combination of the pump 78, the conduits 80a, 80b, the external heat source, and the cardboard cartridge to enable alternative forms of lubrication. In some embodiments, the shredder 10 may be provided with an oiling mechanism as described in U.S. Pat. No. 7,798,435, incorporated herein in its entirety, in addition to the lubrication system 50 described above to enable alternative forms of lubrication.
It is contemplated that the lubrication system 50 may be used with any type of shredders 10 and machines and are not limited to the embodiments described above.
While the principles of the invention have been made clear in the illustrative embodiments set forth above, it will be apparent to those skilled in the art that various modifications may be made to the structure, arrangement, proportion, elements, materials, and components used in the practice of the invention.
It will thus be seen that the objects of this invention have been fully and effectively accomplished. It will be realized, however, that the foregoing preferred specific embodiments have been shown and described for the purpose of illustrating the functional and structural principles of this invention and are subject to change without departure from such principles. Therefore, this invention includes all modifications encompassed within the spirit and scope of the following claims.
| Number | Name | Date | Kind |
|---|---|---|---|
| 1405151 | Overstrom | Jan 1922 | A |
| 2530249 | Lee | Nov 1950 | A |
| 3315438 | Kostur | Apr 1967 | A |
| 4534229 | Funk et al. | Aug 1985 | A |
| 5186398 | Vigneaux, Jr. et al. | Feb 1993 | A |
| 5494229 | Rokos et al. | Feb 1996 | A |
| 5799887 | Kroger | Sep 1998 | A |
| 5961058 | Kroger | Oct 1999 | A |
| 6003796 | James | Dec 1999 | A |
| 6212355 | Bunn et al. | Apr 2001 | B1 |
| 7677483 | Romanovich et al. | Mar 2010 | B2 |
| 7798435 | Matlin | Sep 2010 | B2 |
| 7946514 | Matlin et al. | May 2011 | B2 |
| 8376619 | Akita et al. | Feb 2013 | B2 |
| 8498559 | Zess et al. | Jul 2013 | B2 |
| 8575247 | Shakir et al. | Nov 2013 | B2 |
| 8585358 | Matsuo et al. | Nov 2013 | B2 |
| 20060219827 | Matlin et al. | Oct 2006 | A1 |
| 20070109753 | Bae et al. | May 2007 | A1 |
| 20070221767 | Matlin | Sep 2007 | A1 |
| 20070246580 | Matlin et al. | Oct 2007 | A1 |
| 20070246581 | Matlin et al. | Oct 2007 | A1 |
| 20070246585 | Matlin et al. | Oct 2007 | A1 |
| 20070246586 | Matlin et al. | Oct 2007 | A1 |
| 20080245908 | Romanovich et al. | Oct 2008 | A1 |
| 20100021330 | Haller | Jan 2010 | A1 |
| 20100051731 | Matlin et al. | Mar 2010 | A1 |
| 20100084496 | Matlin et al. | Apr 2010 | A1 |
| 20110297769 | Matlin et al. | Dec 2011 | A1 |
| Number | Date | Country |
|---|---|---|
| 202009016673 | Oct 2010 | DE |
| Entry |
|---|
| International Search Report and Written Opinion regarding PCT/US2012/044359, mailed Oct. 29, 2012, 64 pages. |
| International Preliminary Report on Patentability issued on Jan. 7, 2014 in PCT/US2012/044359. |
| Number | Date | Country | |
|---|---|---|---|
| 20130001342 A1 | Jan 2013 | US |
