Domestic refuse compactor
i United States Patent [1 .1 [[11] 3,874,282 Oouchi 5] Apr. 1, 1975 DOMESTIC REFUSE COMPACTOR Primary Examiner-Billy J. Wilhite [75] Inventor: Keizi Oouchi, Hitachi, Japan Attorney Agent or Flrm cralg &amp; Antone! 73 A&#39; :H&#39;t h&#39;,Ltd.Tk ,J&#39; l ssignee me 1 0 yo apan ABSTRACT [22] Filed: Aug. 23, 1973 l A domestic refuse compactor comprising a&#39;cabinet PP bio-1390507 with a front entrance, a device for compressing or crushing refuse, an arrangement for holding a refuse- 30 F A P D t receiving container accommodated in the cabinet se- 1 A gg g i [on y a a 47 86188 lectively movably betgween an inner hidden position i for refuse compaction and an outer exposed position for placement or removal of the refuse, a motor for [2%] 100/53 100/ the compressing-crushing device, a key switch mecha- 64 61 nism for the motor, and a mechanism for locking the 1 241. 2 2 refuse-container holding arrangement in the inner pol sition for compaction. The key switch mechanism is operatively connected to the locking mechanism so [56] References C&#39;ted that it can work only when the latter is operable, and UNITED STATES PATENTS has a cam which can close a microswitch for power 3.613.560 10/1971 Bottus et al 100/53 supply and, at the same time, actuate a spring-loaded 3.654.855 4/1972 Longo 100/229 A to er f the lock mechanism to lock the door sel Tang X curely the machine is in Operation 3,772,984 1 1/1973 Karls ct a1 100/229 A 4 Claims, 4 Drawing Figures L x l 3 7 r 2 FT /4 DOMESTIC REFUSE COMPACTOR BACKGROUND OF THE INVENTION This invention relates to a domestic refuse compactor and is particularly concerned with a compactor that compresses and packs the household trash, such as wastepaper and newspaper, rags, emptied cartons, cans and bottles, and garbage, into paper bags for efficient and hygienic disposal of the refuse.  
  As is well known, the disposal of wastes is becoming a matter of major social concern, posing a serious problem not only for the national and local government authorities concerned but also for the individual families. As attempts contributory to the solution of the problem, some varieties of refuse compactors for household use have been proposed. They invariably comprise an electric motor and a press means for compressing or crushing the refuse deposited therein, packing the compact mass of refuse in a bag for subsequent removal. For the compaction purpose the existing machines exert fairly great compressive forces, and it means that careless handling of the compactors can lead to dreadful accidents. To avoid such hazards, perfect safety devices are indispensable and, especially because the machines are intended for domestic use, provision of such safety devices is required which need no skill in handling and are as troublefree as possible.  
  The domestic refuse compactors hitherto proposed have been usually equipped with two or three safety devices, quite common in types, to protect the users. The ordinary safety devices include, for example, keyoperated, door or drawer, and emergency stop switches. The key-operated switch, designed to preclude playful handling of the machine by children, comprises a cylinder key or other key means built in the compactor cabinet and is associated with a switch for closing a power supply circuit only when a key is inserted into the switch. The door or drawer switch is actuated by the movement of a door or drawer of the compactor so as to shut off the power supply when the door or drawer is opened for placement of refuse into the compactor. The emergency stop switch cuts off the power circuit in case of an emergency.  
  As noted above, all conventional domestic refuse compactors are provided with such safety devices, which are exactly the same in fundamental principles and concepts, although the details of construction and material vary. Nevertheless, those devices have not always been safe. For example, the key-operated switch may be loosened out of the ON position by the vibration of the compactor during normal operation until the power circuit is unintendedly switched off, bringing the machine to a stop. With the door or drawer switch, which becomes actuated to open or close the power circuit upon the depression of its switch lever by the moving door or drawer, it can happen that the safety switch works before the door or drawer reaches its fully closed position. In extreme cases. the gap thus left between the machine cabinet and the door or drawer may be large enough to admit infants hands into the compactor in operation.  
 SUMMARY OF THE INVENTION It is a principal object of the present invention to provide a domestic refuse compactor equipped with a door or drawer lock mechanism which is actuated by a cam that can also cause the above-mentioned key-operated switch to open or close the power supply circuit, so that the key switch is not actuated unless the door or drawer is completely closed and, while the machine is operating with the key switch turned on, the door or drawer remains locked unopenably.  
  Another object of the invention is to provide a compactor wherein the reaction force of a return spring provided in the door or drawer lcok mechanism is utilized to press and hold in position the cam for actuating the key switch and lock mechanism when the cam has been turned beyond its dead center, thereby avoiding the possibility of the cam being brought back past its dead center by the vibration of the compactor and thus stopping the machine.  
 BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a right side view, partly broken away, of an embodiment of the present invention;  
  FIG. 2 is an enlarged sectional view of a portion of the embodiment shown in FIG. 1;  
  FIG. 3 is an inside view as seen in the direction of an arrow III in FIG. 2; and  
  FIG. 4 is a schematic diagram of the electric circuitry for the embodiment.  
 DESCRIPTION OF THE PREFERRED EMBODIMENT The present invention will now be described in more detail hereunder in conjunction with the drawings showing an embodiment of the invention, wherein like reference numerals designate like parts throughout the several views. It is also to be understood that the shapes and relative dimensions of some parts are deformed or exaggerated for a better understanding of the invention.  
  Referring to FIG. 1, there is illustrated a portion of a domestic refuse compactor l equipped with safety devices according to the invention, partly broken away to show the construction. On the machine base 2 is mounted an electric motor 3, and four frame members 4 are held upright. Surrounded by these frame members 4 is a ram 5, which is adapted to move up and down along the frame members serving as guide rails. The ram 5 has a ram head 5a secured to its underside and also carries spherical nuts (not shown) attached by a housing 6 in a self-aligning manner. The nuts are in thread engagement with two screw shafts 7 at the right and left of the cabinet. The lower ends of screw shafts 7 are rotatably journaled in the base 2 so that, when the rotational power motor 3 is transmitted thereto via transmitting means such as gearing or roller chain (not shown), the shafts rotate to move the spherical nuts in their axial directions. In this way the rotational power is converted into the vertical motion of the ram 5 to which the nuts are attached. Immediately below the ram 5 and ram head 5a there is placed an open-top refuse box 8 on base 2. The inner side of a door 10 turnably hinged at its lower end to a stationary pin 9 on base 2 is disengageably connected to the front side of refuse box 8. Thus. it will be appreciated that, when the door 10 is opened by turning it down frontward, the refuse box 8 is tilted forward, too. A handle 11 is provided at the upper end of door 10, and above the handle there are mounted a key switch mechanism 12 and a door lock mechanism 13. In contact with the lower part of the rear side of refuse box 8, a safety switch 14 is fixed to base 2. In the state shown, the switch at the rear of refuse box 8 is closed, thereby establishing the power supply circuit. The arrangement is such that, when door 10 is opened, refuse box 8 inclines frontward thereby opening the safety switch and shutting off the power supply.  
  FIGS. 2 and 3 illustrate the details of the key switch mechanism. 12 and door lock mechanism 13. In these figures, there are shown a key 15, a front panel 16 of the cabinet, a bracket 17 supporting a microswitch to be described later, and a lock nut 18 fixing a cylinder key body 19 to front panel 16. This lock nut 18 also secures bracket 17 to front panel 16. Cylinder key body 19 comprises an inner cylinder 19a adapted to be re volved by key and an outer cylinder 19b that accommodates the inner cylinder revolvably therein. Outer cylinder 19b is formed with a steplike extension 19c at its internal end. A cam 21 for actuating the microswitch and lock mechanism is fastened to the inner cylinder 1911 by a screw 20. The cam is formed with an outward protuberance 21a which, when the cam has been turned to the position indicated by solid lines in FIG. 3, engages with the steplike extension to keep the cam from further turning. It is so designed that, whenever its protuberance 21a and extension 19c engage in the manner described, the cam is in the position slightly beyond its dead center as indicated by the solid lines in FIG. 3. As cam 21 moves past the dead center, the actuating lever. 23 of a microswitch 22 is pushed to close the power circuit. At the same time, a stopper 24 is pushed down against the reaction force of a return spring 25 to enter holes 26 superposedly formed in the I door 10 and the handle 11.  
  With the construction above described, the compactor ac cording to this invention is operated in the following manner. As the microswitch 22 of key switch mechanism 12 is closed, stopper 24 of door lock mechanism 13 will work, without fail, to lock the door 10. When the user, desiring to open the door, turns the key 15 to pull off stopper 24 from holes 26 by dint of the reaction force of return spring 25, the microswitch 22 is opened and the power circuit is thereby cut off. Return spring 25 also serves to prevent the loosening of cam 21 because it absorbs the vibration of the compactor in operation.  
  Theelectric circuitry including safety switch 14 and microswitch 22 is schematically shown in FIG. 4. An emergency stop switch 27, which is normally closed and is actuated in an emergency to cut off the power supply circuit, is disposed in series with microswitch 22 on one ends of power supply leads. Adjacent to these switches, a starting switch 28 of the repulsion type, which is closed as long as it is depressed and is opened upon releasing by the user, is arranged in parallel to a top limit switch 29, which is opened when ram 5 has ascended to its preset upper position and is closed as the ram commences the downward movement. Beyond these switches is located safety switch 14 and, still farther, as shown, there are provided motor 3 and a change-over switch 30 (which changes the connection of starting coil upon the initiation of the upward or downward movement of ram 5 over to a forward or reverse run). Although, these components constitute the power supply circuit. The circuit thus established is cut off if any one of the safety switch 14, microswitch 22, and emergency stop switch 27 is opened.  
  In order to operate the compactor, the user inserts key 15 into a corresponding slot and turns it thereby actuating microswitch 22 and then presses starting switch 28. This closes the power circuit and enables motor 3 to drive screw shafts 7, which in turn begin to bring ram 5 downward. The downward movement of ram 5 immediately causes the top limit switch to close, whereby the circuit is kept closed even after the user has released the starting switch, and the ram continues to come down, either compressing or crushing the refuse in the box. After the ram has reached the lower limit of its travel, change-over switch 30 enables the ram to shift its direction, this time upward. As soon as the ram reaches its upper position, the top limit switch is actuated to shut off the power supply. The ram thus completes one cycle of operation.  
  While the domestic refuse compactor of the invention has been described in the form of an embodiment with a door openable by letting it down frontwardly, it  
 is to be understood that the invention is not limited thereto but the combination of the let-down type door and refuse box may be supplanted by any other convenient combination, for example, by an arrangement wherein the refuse box of the illustrated embodiment takes the form of a drawer that can be drawn out frontward or an arrangement using a common door that can be swung open sidewise to the right or left. It should.  
 also be appreciated that the concept of the invention is equally applicable to arrangements wherein the safety devices of the invention are combined, for example, with lock and alarm means for room doors or with door and alarm means of safes.  
  With the domestic refuse compactor incorporating the safety devices according to this invention, the user who desires to start the machine simply inserts .a key into the key slot and turns. This enables the actuating lever of the microswitch of the key switch mechanism to be raised by the cam while, at the same time, the  
 stopper of the lock mechanism is pushed down againstthe reaction force of the return spring to get into the holes of the door and handle. Thus, as long as the microswitch is closed, the door remains locked.  
  Unless the door is completely closed, the stopper of the lock mechanism is unable to fit into the holes of the door and handle. Consequently, the stopper cannot be pushed down to its lower limit of travel and the cam cannot be turned, and hence the microswitch of the key switch mechanism cannot be closed.  
  Since the stopper of the lock mechanism is under the upward urging of the return spring, the cam that has been turned by the key to a point slightly beyond its dead center is pushed by the upper end of the stopper. Moreover, because the return spring absorbs the vibration of the machine, there is no possibility of the cam moving back to its original position by itself or by the mechanical vibration and thereby opening the switch of the key switch mechanism.  
  With the foregoing functions made possible by the present invention, there is no longer the danger of domestic refuse compactors being operated with the doors not closed tight, and more perfect safety devices than heretofore can be provided.  
  In addition, the possiblity of the switch of the key switch mechanism being turned open by the vibration of the machine in operation is eliminated by the provision of the safety devices in accordance with this invention. A further advantage is that the safety system provided by the invention is more inexpensive than the ordinary arrangement in which the door lock mechanism is installed independently of the other safety devices.  
 I claim:  
 1. A safety key switch device comprising:  
 microswitch means, locking means, and a cam member installed in the key switch device in such a manner that it moves upon actuation to a position which simultaneously closes the microswitch means and actuates the locking means,  
 wherein said locking means includes return spring means for pressing an end of said locking means against the cam member, wherein said cam member has a configuration which is longer in one of its length and its width,  
 wherein said key switch device includes means to stop the cam member in said position slightly beyond its dead center when the key switch device is actuated, so that the spring means operates to avoid movement of the cam out of said position, and  
 wherein the device is operationally connected with a machine in such a manner that the locking means locks a door of the machine when actuated and the microswitch means actuates an electric motor drive of the machine when closed.  
  2. A device according to claim 1, wherein the machine is a refuse compactor.  
  3. A domestic refuse compactor comprising a cabinet base, compressing-crushing means installed on the base to compress or crush refuse contained in refuse receiving means,  
 motor means for driving the compressing-crushing means, key switch means for the motor means, and locking means for locking a refuse receiving holding means, said key switch means being operatively connected to the locking means in the condition where the locking means is actuated, wherein said key switch means includes microswitch means, wherein cam means is installed in the key switch means in such a manner that the cam means moves upon actuation to simultaneously close the microswitch means and actuate the locking means, wherein said locking means has return spring means that presses one end of the locking means against the cam means, and wherein said key switch means has means to stop the cam means in a position slightly beyond its dead center when the key switch means is actuated, so that a spring force of the spring means can be utilized to absorb vibrations of the compactor and to avoid movement of the cam means out of said position. 4. A compactor according to claim 3, wherein the locking means is a stopper, wherein the locking means further comprises means for holding the refuse receiving means selectively movably between a preset inner position for compaction on the base and an outer exposed position where the compact mass of refuse is to be removed from the compactor, and wherein the locking means locks the refuse receiving holding means in a preset position.