Abstract:
A secure disposal system for articles having a movable enclosure that is fully enclosed except for an opening to receive articles. The movable enclosure has a releasable lock for automatically locking a cover in a closed position on the movable enclosure. A transfer device automatically unlocks the cover of the movable enclosure in response to the transfer device mechanically engaging the movable enclosure. The transfer device transfers the enclosure to a position and orientation permitting the cover of the enclosure to fall open and the articles to drop from the enclosure. An article destroyer is located adjacent the transfer device, receives the articles dropping from the movable enclosure and destroys their functionality.

Description:
FIELD OF THE INVENTION 
     This invention relates to material handling and more particularly, to a system for handling and disposing of articles, for example, optical discs. 
     BACKGROUND OF THE INVENTION 
     In many production environments, articles are often produced in batches for particular customers. Although a customer orders a desired quantity of articles, in some applications, it is normal practice to run a batch of articles that is in excess of the desired quantity. Thus, as the articles proceed through the various steps of the production process, if lesser quality or scrap articles are produced, the batch will still have a net yield of articles that is sufficient to ship the desired quantity to the customer. Further, most often, the batch will yield a quantity of good, high quality articles that is in excess of the desired quantity, and those excess articles potentially have full market value. Depending on the articles, their unauthorized distribution may potentially create a liability for the manufacturer. For example, if the articles are optical discs that contain copyrighted music and/or movies, an unauthorized distribution or sale of such excess production optical discs may be illegal. Therefore, if the excess production discs cannot be sold to the customer, the manufacturer normally, as a minimum, destroys the readability of the optical discs prior to disposal or recycling. 
     However, there are no known systems for securely handling excess optical disc production from the time that it has been produced until the time that it is initially processed for recycling or disposal. In known manufacturing environments, there are minimal or no facilities for physically securing excess optical discs while they are being transported from a production station to a machine that destroys their readability. Thus, there are opportunities for the optical discs to leak, that is, be removed, from the production facilities. Further, with some batches, the number of excess optical discs is significant, and therefore, their loss represents a loss of a significant value. 
     Consequently, there is a need for a material handling system for articles of excess production that is more secure, reliable and automated than known systems. 
     SUMMARY OF THE INVENTION 
     The present invention provides a simple and reliable system for securely handling and destroying the functionality of articles. The system of the present invention automatically locks access to the articles during their collection, thereby securing the articles during their transportation. Further, the system of the present invention automatically unlocks access to the articles immediately prior to their destruction. Thus, the secure disposal system of the present invention is especially useful in an environment in which optical discs containing copyrighted material are produced. The secure disposal system of the present invention has the advantages of first, efficiently handling optical discs identified for destruction and, second, reducing a potential for liability caused by an unauthorized distribution or sale of such optical discs. 
     According to the principles of the present invention and in accordance with the preferred embodiments, the invention provides a secure disposal system for articles having a movable enclosure that is fully enclosed except for an opening to receive articles. The movable enclosure has a releasable lock for automatically locking a cover in a closed position on the movable enclosure. A transfer device automatically unlocks the cover of the movable enclosure in response to the transfer device mechanically engaging the movable enclosure. The transfer device transfers the enclosure to a position and orientation permitting the cover of the enclosure to fall open and the articles to drop from the enclosure. An article destroyer is located adjacent the transfer device, receives the articles dropping from the movable enclosure and destroys their functionality. 
     In one aspect of the invention, the movable enclosure has a first member; and the transfer device has a lift arm. The releasable lock is unlocked as the first member receives the lift arm, thereby releasing the cover from the enclosure. 
     In another aspect of the invention, the movable enclosure is a wheeled cart and the transfer device includes a rotary drive. The rotary drive inverts the wheeled cart, thereby by allowing the cover to fall open and the articles to drop into the article destroyer. 
     In another embodiment of the invention, a method is provided for automatically locking a cover of a movable enclosure upon the cover closing over the movable enclosure. As the movable enclosure is moved onto a transfer device, the cover is automatically unlocked; and thereafter, the transfer device is operated to transfer the articles from the movable enclosure into an article destroyer. Thus, the articles are locked in the movable enclosure until the movable enclosure is moved onto the transfer device, and the articles are discharged into the article destroyer immediately after the cover of the movable enclosure is automatically unlocked. 
     These and other objects and advantages of the present invention will become more readily apparent during the following detailed description taken in conjunction with the drawings herein. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of the secure disposal system for articles in accordance with the principles of the present invention. 
     FIG. 2 is a perspective view of a wheeled cart used with the secure disposal system for articles of FIG.  1 . 
     FIG. 3A is a partial perspective view illustrating a releasable cover lock for the wheeled cart of FIG. 2 in its locked position. 
     FIG. 3B is a partial perspective view illustrating a releasable cover lock of FIG. 3A in its unlocked position. 
     FIG. 4 is a perspective view of a portion of the transfer device illustrated in FIG.  1 . 
     FIG. 5 is a perspective view of the article disposal system of FIG. 1 illustrating the wheeled cart being lifted by the transfer device to a position and orientation permitting the articles therein to be discharged. 
     FIG. 6 is a schematic block diagram of a control used to operate the secure disposal system of FIG.  1 . 
     FIG. 7 is a flowchart of a cycle of operation executed by the control of FIG.  6 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to FIG. 1, a secure disposal system  20  for articles is comprised of a mobile cart  22 , a transfer device  24 , an article accumulator or hopper  26  and an article destroyer  28 . One example of an article destroyer  28  is a rotary grinder model RG 42EW commercially available from ReTech Industries, Inc. of High Point, N.C. Such a rotary grinder  28  has a cutting or grinding tool  29  that grinds the articles or optical discs into small pieces that drop into a collector  31 . The ground optical disc material in the collector  31  is transported away from the article disposal system  20  by a pneumatic transfer system  44 . In many manufacturing environments, scrap articles are produced in the normal course of production. In other environments, for example, in the production of optical discs containing audio and video material, overrun production is common. The secure disposal system  20  of FIG. 1 is especially useful for collecting and destroying nondefective, good articles such as optical discs that have a commercial value and the unauthorized distribution and sale of which may be illegal. 
     The cart  22  has a hinged cover or lid  30  that is normally locked or secured in its illustrated, closed position. The cover  30  has slots or openings  32  that permit articles, in this example, optical discs, to be loaded into the cart  22 . The cart  22  is manually or automatically moved to various production stations, and overproduction and/or scrap optical discs are inserted through the openings  32  and dropped into the cart  22 . After the optical discs have been loaded into the cart  22 , the automatic securing or locking of the cover  30  to the cart  22  prohibits removal of the optical discs. Thus, the cart  22  is a secure facility for storing the optical discs therein. 
     At appropriate times, the cart  22  is moved into juxtaposition with the transfer device  24 . The transfer device  24  has a pair of lift arms  34  that are sized to be received by hollow members or rails  36  on the cart  22 . As will subsequently be described in detail, insertion of the arms  34  into the hollow rails  36  automatically unlocks the cover  30 , thereby permitting the cover  30  to pivot freely with respect to the cart  22 . After the cart  22  is mounted on, or coupled engaged with, the transfer device  24 , the transfer device  24  raises the lift arms  34  and the cart  22 . The lift arms  34  and cart  22  are then rotated to a position illustrated in FIG.  5 . With the cart  22  in its inverted position, the cover  30  falls open; and the articles in the cart  22  drop onto a chute or ramp  38  and then, drop through a first opening  40  of the article accumulator or hopper  26 . The articles then pass through a second hopper opening  42  and into a chamber or throat of the article destroyer  28 . 
     Referring to FIG. 2, the cart  22  is normally a rectangular enclosure having four sidewalls  46  and a bottom wall  48 . The enclosure of the cart  22  may be made of any suitable material, for example, welded aluminum sheets. The cover  30  forms a top wall and is pivotally connected to one of the walls  46  by a hinge formed by a pair of sleeves  50  that are rigidly attached, for example, by adhesives, fasteners, welding, etc., to the underside of the cover  30  along its rear edge. The sleeves  50  are rotatably mounted on a shaft  51 , so that the cover  30  rotates freely with respect to a generally horizontal pivot axis  53 . The ends of the shaft  51  are fixed or secured within the ends of the siderails  36 , for example, by adhesives, fasteners, welding, etc. A handle  52  is also rotatably mounted on the shaft  51  and it also rotates freely with respect to the pivot axis  53 . Thus, when released, the handle  52  normally rests in a lower-most position against the rear side of the cart  22 . The handle  52  is held in its lower-most position by a magnet (not shown) on the cart rear side, so that it does not move without being gripped by the user of the cart  22 . Thus, the position of the handle  52  illustrated in FIG. 2 is only possible if the handle  52  is being supported in that position by a user of the cart  22 . The handle  52  is made of any suitable rigid material, for example, welded aluminum tubing. When lifted to the illustrated position, the handle  52  can be used to push and steer the cart  22 . The cart  22  further has a pair of rear wheels  56  that are mounted to the cart  22 . A pair of front wheels  58  are mounted to respective casters  60  that are, in turn, are pivotally attached to the cart  22  in a known manner. 
     Referring to FIG. 3A, the cover  30  is secured to the cart  22  by a releasable latch  62  engaged in a hole  64  of a keeper  66 . The keeper  66  is welded or otherwise rigidly connected to an underside  67  of the cover  30 . The latch  62  is normally made from a resilient, metal spring material and has a first, proximal end  68  welded or otherwise rigidly connected to a side surface  70  of the hollow rail member  36 . The latch  62  has a body portion  72  that bends in a first direction and projects inward through a cutout or opening  74  in the sidewall  70  of the hollow rail  36 . The body portion  72  thus extends into the cavity  76  of the hollow rail  36 . 
     A second, distal end  78  of the latch  62  is generally J-shaped and has a longer leg  79  that extends in a second direction opposite the first direction, that is, outward from the opening  74 . A shorter leg  80  extends back in the first direction through a hole  64  of a keeper  66 . The positioning of the shorter leg  80  of the latch  62  in the hole  64  of the keeper  66  locks or latches the cover  30  in a closed position on the cart  22 . Therefore, the cover  30  cannot be lifted, and articles or optical discs in the cart  22  are secured from being removed therefrom. Although FIG. 3A illustrates the cover latch  62  or locking mechanism in one of the hollow rails  36 , as will be appreciated, the cover latch  62  may be used in either or both of the hollow rails  36 . 
     Referring to FIG. 1, the transfer device  24  has a frame  82  that supports a linear drive, for example, a rodless air cylinder  84 . A fork assembly  86  supports the pair of lift arms  34  and is rigidly connected to a movable portion (not shown) of the cylinder  84 . The fork assembly  86  is also mounted on a pair of guiderails  88  that guide its motion in a generally vertical direction. Referring to FIG. 4, the lift arms  34  of the fork assembly  86  are rigidly connected to a frame  90 . The frame  90  is rotatably connected to the fork assembly  86  by means of a pair of axles or spindles  92  that are mounted inside bearing blocks  94 . 
     A rotary drive, for example, an electric motor,  96  is connected to the frame  90  by mechanical drive, for example, a looped chain  98  and gear  100 . The gear  100  is substantially larger than a gear (not shown) on an output shaft of the motor  96  in order to provide the motor  96  with a large mechanical advantage. The rotary drive  96  may be an electric servomotor or any other appropriate electric or hydraulic motor and drive that is capable of providing an angular motion. The chain and gear drive may be replaced by a toothed belt and pulley or any other mechanical linkage that is sufficiently strong to rotate the cart  22  as will be described. In one application, the cart weighs about 100 pounds and has a load carrying capacity of about 150 pounds. Operating the rotate motor  96  is effective to rotate the fork assembly  86  and cart  22  through an angular displacement about an axis of rotation  102 . The exact magnitude and limits of the angular displacement of the fork assembly  86  are variable and normally programmable and/or controlled by proximity switches, for example, limit switches, either external or internal to the motor  96  in a known manner. However, in order to properly empty the cart  22 , the angular displacement of the fork assembly is about 180°. 
     Referring to FIG. 6, the secure disposal system is controlled by a programmable logic controller (“PLC”)  110 . The controller  110  has inputs provided by operator input/output devices (“I/O”)  112 , for examples, pushbuttons, a keyboard, touchscreen or other known input devices. In addition, the PLC  110  has inputs from limit switches  114 ,  116  that are provided with the lift cylinder  84 . The limit switches  114 ,  116  produce outputs in response to the lift cylinder being in its up and down positions, respectively. The rotate motor  96  also has limit switches  118 ,  120  that provide outputs to the PLC  110  in response to the rotate motor being through its angular displacement. Further, the PLC  110  receives input signals from a sensor  122  that detects when the hopper  26  is full. Other limit switches  138 ,  140  indicate when the ram cylinder is fully extended and the hopper  40  is full. As will be appreciated, the operation of the article destroyer may require other devices as well as other input and output signals; however, such devices and signals are not necessary for a full understanding of the claimed invention and will not be described herein. 
     In use, a user grabs and lifts the handle  52  (FIG. 2) of the wheeled cart  22  from its magnetically latched rest position and uses the handle  52  to move the cart  22  to desired locations, for example, different processing stations, within a production environment. Articles to be disposed of, for example, scrap optical discs and/or overruns of printed optical discs, are placed in the openings or slots  32  of the cover  30 . When the cart  22  either contains, or is filled with, optical discs, the cart  22  is then moved to the transfer device  24  shown in FIG.  1 . 
     The cart  22  is maneuvered so that the pair of hollow rails begins to slide over the pair of lift arms. Referring to FIG. 3B, as a lift arm  34  slides into the opening  76  of a hollow rail  36 , a side surface  81  of a lift arm  34  contacts and pushes against the main body  72  of the latch  62 . The side surface  81  pushes the latch  62  in the second direction outward through the opening  74  of the hollow rail  36 . Simultaneously, the shorter leg  80  of the latch  62  moves in the second direction out of the hole  64  of the keeper  66 , thereby automatically unlocking or releasing the cover  30  from the cart  22 . Thus, when the cart  22  is properly positioned on the arms  34  of the transfer device  24 , the cover  30  can be pivoted and opened with respect to the cart  22 . 
     Next, the operator I/O  112  (FIG. 6) is used to provide a start command that initiates the disposal cycle illustrated in FIG.  7 . Upon receiving the start command at  700 , the PLC  110  then, at  702 , checks the state of a cart sensor  111  (FIG. 6) associated with the fork assembly  86 . The cart sensor  111  may be any device that is able to detect that the cart  22  is located at its proper position on the arms  34 . Thus, the cart sensor  111  may be an IR sensor or a proximity switch, for example, a limit switch, located on the frame  90  (FIG. 4) of the fork assembly. If the cart sensors  111  do not detect the cart  22  on the lift arms  34 , the PLC  110  provides an error message at  703  to the operator via the operator I/O  112 . 
     If the cart  22  is present on the arms, the PLC  110  then, at  704 , provides a command signal to a solenoid valve  126  that ports fluid to the lift cylinder  84  in a direction causing the lift cylinder  84  to raise the fork assembly  86  and the cart  22 . A lift cylinder up limit switch  114  provides an input signal to the PLC  110  in response to the lift cylinder reaching its fully raised position. The PLC at  706 , detects the raised position and then, at  708 , provides an output command to a motor drive  128  that, in turn, operates the motor  96  in a direction to rotate the fork assembly  86  and cart  22  over the hopper  26  in a counterclockwise direction as illustrated in FIG.  5 . 
     The PLC  110  detects, at  710 , an output signal from a proximity sensor, for example, rotate motor up limit switch  118 , when the rotate motor  96  reaches its desired position. The PLC  110  then, at  712 , commands the motor drive  128  to stop the motor  96 . As the cart  22  rotates counterclockwise, the cart  22  is inverted; and the cover  30  falls open; and optical discs drop from the cart  22 , slide down chute  38  and drop through first opening  40  into the hopper  26 . To allow for that activity, PLC  110  utilizes an internal timer to effect a dwell or delay and, at  714 , checks to determine when that time period expires. 
     When the expiration of the dwell time is detected, the PLC  110 , at  716 , provides command signals to the motor drive  128  causing it to operate the motor  96  in the opposite direction, thereby rotating the cart  22  generally clockwise as viewed in FIG.  5 . At  718 , a proximity sensor, for example, a motor down limit switch,  120  provides an input signal representing the original, generally horizontal and upright position of the cart  22 ; and at  720 , the PLC  110  commands the motor  96  to stop. Simultaneously, the PLC  110  commands the solenoid drive  126  to reverse its state, thereby porting fluid to the lift cylinder  84  in a direction causing the lift cylinder to lower. A lift cylinder down limit switch  116  provides an input signal that is detected by the PLC  110  at  722 . 
     At this point, the cart  22  is again resting on the floor and can be moved off of the arms  34  by using the handle  52 . As the hollow rails  36  slide off of the arms  34 , referring to FIG. 3A, the side  81  of the arm  34  is moved out of contact with the main body  72  of the latch  62 . The resiliency of the latch  62  causes the latch  62  to move in the first direction back through the opening  74  and back into the cavity  76  of the hollow rail  36 . In doing so, the smaller end  80  of the latch  62  again moves back into the hole  64  of the keeper  66 ; and the cover is automatically locked or secured in its closed position on the cart  22 . 
     Thereafter, the PLC  110 , at  724 , checks the state of the hopper full limit switch  122 . If the hopper  26  is not full, subsequent cart loads of optical discs are loaded into the hopper until the sensor  122  detects that the hopper  26  is full. At  726 , the PLC  110  provides an output to the motor drive  130  commanding a grinder motor  132  to start. Simultaneously, at  727 , the PLC  110  provides an output signal to a solenoid valve  134  commanding a ram cylinder  136  in the hopper  26  to begin to extend. Thus, the grinder  28  is operating to grind up the optical discs that are in the hopper  26 . Further, the operation of the ram continues to feed optical discs into the shredder. A ram cylinder out limit switch  138  provides a signal to the PLC  110  indicating that the ram is fully extended. That signal is detected at  728 , and at  730 , the PLC  110  provides a signal to the solenoid valve  134  causing it to reverse its state and port fluid to the ram cylinder  136  in a direction causing the ram cylinder to retract. If, at  732 , the PLC  110  determines that the hopper  40  is not empty, the process of steps  727 - 730  is repeated until all of the discs in the hopper  40  have been destroyed. Upon the PLC  110  detecting, at  732 , an output signal from a hopper empty limit switch  140  indicating that the hopper is empty, the PLC  110  then, at  736 , provides an output signal to the motor drive  130  commanding the grinder motor  132  to stop. The ground pieces of the optical discs are transported by the pneumatic transfer system  44  to another location for further processing, for example, recycling. 
     The present invention provides a simple and reliable system for securely handling and destroying the functionality of articles. The system automatically locks a cover of an article container, thereby maintaining the articles secure during their collection and transportation. Further, the system automatically unlocks the cover of the container immediately prior to their destruction. Thus, the secure system described herein is especially useful in an environment in which optical discs containing copyrighted material are produced. The secure disposal system described herein has the advantages of first, efficiently handling optical discs identified for destruction and, second, reducing a potential for liability caused by an unauthorized distribution or sale of such optical discs. 
     While the invention has been illustrated by the description of one embodiment and while the embodiment has been described in considerable detail, there is no intention to restrict nor in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those who are skilled in the art. For example, in the described embodiment, the article destroyer is described as a grinder with a rotating cutting tool. As will be appreciated, the article destroyer may be any other piece of equipment that is capable of either, destroying only the functionality of the articles or, fully destroying the whole article. 
     Therefore, the invention in its broadest aspects is not limited to the specific details shown and described. Consequently, departures may be made from the details described herein without departing from the spirit and scope of the claims which follow.