This invention pertains to trash compactors and trash compactor mechanisms for use in restaurant dining rooms, kitchens and the like that periodically compact trash into a trash receptacle at the bottom of the unit.
Trash compactors are useful because they reduce the frequency that a particular trash collection unit needs to be emptied and they reduce the overall volume of trash collected. For example, in restaurant dining rooms, the principle components of the waste are napkins, sandwich wrappers, paper cups and food waste. In a typical fast food restaurant, patrons can fill a trash container with these low density item quickly. The trash container, filled with low density waste, needs to be emptied by an employee more frequently and such trash fills up a dumpster or other collection unit more rapidly. In contrast, a dining room trash compaction unit is filled up by patrons over a longer period of time and produces a higher-density waste. Thus, trash compaction units need to be emptied by employees less often and a single dumpster can hold more waste. This reduces costs.
Most trash compactors share a basic design; a horizontal platen is pressed downwards to compress trash into a receptacle at the bottom of the trash compactor. One point of difference among trash compactor designs is in the mechanism used to actuate the platen. For example, in U.S. Pat. No. 6,367,377 to Gawley et al., a scissors-type mechanism is operated by a horizontal screw actuator. One set of feet are connected to the platen and another set of feet slide in a pair of tracks or on a rack-and pinion of the platen. As the platen is forced downward to compress the trash, the screw experiences ever increasing bending moments and the forces from the scissors mechanism on the platen are applied in an increasingly asymmetric manner. The parts of the mechanism need to be beefier to compensate for this disposition of forces. Further, there is a chance that debris might become lodged between the sliding feet and the rack-and-pinion mechanism in the platen, which would jam the mechanism. Another typical prior art design is found in U.S. Pat. No. 4,100,850 to Wolbrink et al., where the electric motor powering the compacting mechanism moves up and down with the compacting mechanism. This type of design puts undue stress on the electrical leads as they flex to follow the motor through the compaction cycle and the platen does not follow a perfectly vertical path. U.S. Pat. No. 4,024,806 to Weeks et al. describes a trash compactor that requires two vertical screws to drive the compacting mechanism and stabilize the platen.
What is desirable is for further trash compactor designs that reduce the chance of contaminating the compacting mechanism with trash, increase reliability and safety, and reduce cost.
In a first aspect, there is an apparatus for compacting trash. The apparatus includes a compacting mechanism that has multiple sets of linkages that are connected by a simple hinge joint to the platen and to the frame of the apparatus. The linkages may be driven by a single vertical screw actuator. At least one set of linkages operates in a plane that is at an angle to the plane of another set of linkages. In one preferred embodiment, a single vertical screw actuator drives four sets of linkages, two of which are disposed in planes that are perpendicular, or normal, to the planes of the other two sets of linkages.
In another aspect, the sets of linkages are connected to the vertical screw actuator by a movable plate, which the screw actuator moves up and down. This connection of the sets of linkages to the movable plate may involve an additional linkage to each set of linkages.
Another embodiment involves a set of linkages attached to a drive mechanism to provide force to move the platen up and down. Another set of linkages is attached to the drive mechanism and two additional sets of linkages are attached to the frame of the embodiment at an angle to the first set of linkages to provide stability and balance to the platen.
Another aspect provides for a platen that includes a wide rim disposed around the bottom plate of the platen and may include an outward lip above the rim. The platen may also include one or more beveled edges to the bottom plate.
Another aspect provides for an inlet door, for a user to dispose of trash into the trash compactor, that can be opened by the user or by an inlet door opening mechanism. The inlet door opening mechanism may have a portion attached to the inlet door that moves with the inlet door and another portion, which may be attached to the frame, that does not need to move with the inlet door. This portion includes a motor and means to move the portion attached to the inlet door to open the inlet door or to allow the inlet door to close. A proximity sensor may be positioned near the inlet to detect the approach of a user, and one or more sensors may be disposed on the inlet door to detect whether the door is opened or closed.
Another aspect provides for a trash receptacle that may be wheeled out from the trash compactor and in which a compact block of compressed trash of manageable size and weight may be formed and easily removed.
The above summary of some example embodiments is not intended to describe each disclosed embodiment or every implementation of the invention.
The invention may be more completely understood in consideration of the following detailed description of various embodiments in connection with the accompanying drawings, in which:
While the invention is amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit aspects of the invention to the particular embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.
All numeric values are herein assumed to be modified by the term “about”, whether or not explicitly indicated. The term “about” generally refers to a range of numbers that one of skill in the art would consider equivalent to the recited value (i.e., having the same function or result). In many instances, the term “about” may be indicative as including numbers that are rounded to the nearest significant figure.
The recitation of numerical ranges by endpoints includes all numbers within that range (e.g., 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, and 5).
Although some suitable dimensions ranges and/or values pertaining to various components, features and/or specifications are disclosed, one of skill in the art, incited by the present disclosure, would understand desired dimensions, ranges and/or values may deviate from those expressly disclosed.
As used in this specification and the appended claims, the singular forms “a”, “an”, and “the” include plural referents unless the content clearly dictates otherwise. As used in this specification and the appended claims, the term “or” is generally employed in its sense including “and/or” unless the content clearly dictates otherwise.
The following detailed description should be read with reference to the drawings in which similar elements in different drawings are numbered the same. The detailed description and the drawings, which are not necessarily to scale, depict illustrative embodiments and are not intended to limit the scope of the invention. The illustrative embodiments depicted are intended only as exemplary. Selected features of any illustrative embodiment may be incorporated into an additional embodiment unless clearly stated to the contrary.
By way of general overview, a trash compactor 10, shown in perspective view in
The operation of the trash compactor may start with providing a liner for the trash receptacle. When a person approaches the trash compactor, a proximity sensor or other sensor is triggered to open the inlet door, which allows the person to introduce garbage through the inlet door. Alternatively and in at least one embodiment, the inlet door may also open when a person pushes on it. At predetermined intervals the compacting mechanism compacts the trash in the trash receptacle. The trash compactor may provide a signal to indicate that the trash receptacle is full and the liner should be replaced. This may be done by opening up the lower door and wheeling out the trash receptacle.
The housing 12 may be fixed to the frame and may be made of panels of metal, plastic such as acrylic, wood, a combination of such materials or other suitable material or combination of materials. The housing may include, for example, a tray collector molded into its top panel. The housing configuration may vary depending on the contemplated installation of the trash compactor. For example, for a cabinet mounted configured, where only the front panel of the trash compactor is exposed, the housing may be reduced to only the upper and lower doors of the front panel, may eliminate the upper panel, or some other preferred configuration. Lower door 16 may include a lower door latch 26, which may be lockable, and which may be operated to open the lower door. Likewise, the upper door 14 may include a lockable upper door latch 28, which can be operated to open the upper door panel. In this embodiment, the lower door may be opened regularly to provide access to the trash receptacle while the upper door, while operable, needs to be opened only to provide access to service the internal mechanisms of the trash compactor. As can be seen from
Speaker aperture 30 may be a regular array of holes or other opening or set of openings through which a speaker may be heard. In this embodiment, a speaker (not illustrated) is mounted to the frame 24 and does not move with upper door 14 when it is opened. Likewise, signal light aperture 32 may be an opening or set of openings through which a signal light may be seen. Signal light aperture 32 may include a transparent or translucent cover or may be a naked hole in the upper door. The light may be mounted to the frame so that it does not move with upper door 14 when it is opened. Of course, both the speaker and the signal light may be mounted to the upper door if desired or may be located in another part of the housing. Other suitable auditory and visual output mechanisms may be included. Such mechanisms can be used to provide cues and information to users, who are throwing trash into the trash compactor, and service people, who may empty the receptacle and perform other maintenance tasks.
In this embodiment, proximity sensor 34 is mounted in the upper door 14 directly above the inlet door 18 and senses movement near to the sensor. Other contemplated locations for the proximity sensor or for a second proximity sensor include locations on the inlet door. The proximity sensor provides signals to the inlet door opening mechanism and can be adjusted or configured to provide a desired level of sensitivity and range of detection.
Turning now to
The inlet door includes an opening mechanism 40. The opening mechanism has two portions, one of which may be mounted to the upper door and the inlet door and one of which may be mounted to the frame. The two portions are preferably designed to separate when the upper door is opened. The opening mechanism can be seen clearly with reference to
The first portion of the opening mechanism, which is mounted to the upper door and the inlet door, includes a T-shaped linkage 42, the upper end of which rests on a pin 44 and the lower end of which is pivotably connected to a strut 46. Strut 46, in turn, is pivotably connected to the inlet door. Linkage 42 is preferably confined by brackets to the upper door so that it can only move vertically. As the linkage 42 moves up or down, the inner door opens or closes.
The second portion, which is mounted to the frame, includes a motor 48, a rotable arm and a pin 44. The pin is offset from the rotational output of the motor so that the motor can rotate the pin along an arc. Because the T-shaped linkage rests on pin 44, it can be raised either by the pin or independently of it. Further, the upper door can be opening and closed easily, as the link between the two portions of the mechanism is easily separated and rejoined. Of course, any mechanism by which pin 44 can be lifted up and down may be used in the second portion of the opening mechanism. The motor may be selected to retain the position of its output mechanism when power is cut. Thus, for example, if a trash compactor loses power when the inlet door is open, the inlet door will be retained in its position and not close on a user's arm.
Because the first portion of the mechanism can, in some instances, be moved independently of the second portion, there are thus two ways of opening the inlet door 18. In one method, a signal from the proximity sensor is received by a controller, which then tells the motor to rotate. As the pin is rotated by the motor, it slides along the T-shaped linkage while raising its vertical position. As the pin is lifted, so too is the T-shaped linkage, which, because it is mechanically linked to the inlet door, opens the inlet door.
In a second method, the inlet door can be pushed in by a person throwing trash away. The T-shaped linkage is thereby raised independently of the pin. Because the sensors can detect the inlet door opening, the pin can be raised to the T-linkage to keep the inlet door in the open position and to provide for a controlled door closing. Alternatively, pushing on the inlet door triggers one of the inlet door sensors, which sends a signal to the controller. Examples of suitable sensors include solenoids, magnetic sensors, flex sensors and the like. The controller then tells the motor to rotate. In this manner, a person who pushes on the inlet door may be assisted by the opening mechanism in opening the inlet door.
The door mechanism may also include stop limiters (not pictured) attached to the upper door, the housing or the frame to limit the extent that the inlet door may be opened. Of course, other suitable opening mechanisms for the inlet door may be used with various embodiments.
Turning now to
The wheels of the trash compactor or the bottom of the frame provide room for a trash receptacle support 62. The trash receptacle support is a bottom panel piece that includes channels 64 that guide and support the wheels of the trash receptacle. Preferably, the bottoms of channels 64 clear the floor by only a modest distance so that the trash receptacle can be easily wheeled into and off from support 62. The channels may include detents or holes that correspond to the wheels of the trash receptacle. These detents may provide tactile feedback to indicate when the trash receptacle is properly placed, may keep the trash receptacle from rolling out of position and may allow the trash receptacle support, rather than the wheels of the trash receptacle, to bear the brunt of the force during a compaction cycle.
The trash receptacle 22, shown in
Turning now to
Platen 80 is a component with a generally flat bottom surface for compressing the trash into the trash receptacle and may include side walls 81 and upper lip 83 to align the platen within the trash receptacle and to prevent trash from accumulating on the platen. Preferably, the side walls are sized so that the upper lip is always above the trash receptacle. Ordinarily, when trash is being compressed in the trash receptacle, the side walls of the platen are at least partially disposed within the trash receptacle. This confines trash to the trash receptacle and prevents contamination of the compacting mechanism. Further, the upper lip, which extends outwardly from the side walls directs any potential spray of liquid trash away from the compacting mechanism.
It can be appreciated that the cross-sectional shape of the platen 80 and the cross-sectional shape of the trash receptacle should preferably correspond so that the platen is compressing the entire surface of the trash. A square or rectangular shape is the most efficient shape for the platen and the trash receptacle, though of course other shapes, such as circular or octagonal are within certain embodiments. The platen may also include a beveled front edge, which accommodates the opening of the inlet door. A chamfer on the rear edge may also be included. In embodiments that include a rear inlet door, this rear chamfer may accommodate the opening of the rear inlet door. These chamfers also aid in removing trash and add rigidity. In one contemplated embodiment, the platen may include chamfers around the circumference of the flat bottom surface. The flat bottom surface may also include ribs or ridges to create higher and lower pressure areas to better compress the trash.
The drive mechanism is an electric motor 82 connected to one end of the screw actuator by a pulley and belt system. Belt 84, drive pulley 86 and driven pulley 88 are shown. By selecting the electric motor and the diameter of the wheels, one can deliver a desired torque to the screw actuator at a desired rotational speed. This particular drive mechanism keeps the position of the compacting mechanism fixed even when power is turned off, except when the motor is operating, although other drive mechanisms may be used. The screw actuator is fixed vertically within the screw actuator plate and has the same axis of rotation as driven pulley 88 and is free to rotate about its vertical axis. As the screw actuator rotates, it drives the moving plate up and down. The screw actuator may be mounted in the moving plate by use of a floating bearing, which is free to rotate somewhat with respect to the drive plate. This floating bearing connection prevents unwanted forces from building up around the screw actuator. Further, there may be a position sensor on the moving plate to indicate when the plate is in the raised position.
The four linkages 78 are preferably generally symmetrically disposed about the two vertical planes, one between the first and second adjacent linkages and the third and fourth linkages and the other between the second and third adjacent linkages and the remaining two. As can be seen from
The drive plate 74 may include guide blocks 75, which may be made from nylon or other suitable material. These guide blocks may help keep the lateral alignment of the drive plate. Another suitable alignment mechanism may be used as desired in place of or in addition to guide blocks 75.
In one embodiment, the moving plate travels for about 5 inches along the screw to produce about 28 inches of travel in the platen, and the compacting mechanism linkages can fit within an about 23 by about 23 inch square.
Each of the connections to the upper, lower and drive linkages allows one degree of rotational freedom. Such connections shall be referred to herein as simple hinge joints. Simple hinge joints can be formed between the linkages by using pins whose ends are captured using C-rings, by press-fitting a pin into one of the linkages and capturing the other end of the pin with a C-ring, or by some other suitable method. Other components such as roller or ball bearings may be included as well.
The four linkages 78 cooperatively stabilize and fix the position of platen 80. Because the linkages 78 are preferably symmetrical as described above, lateral forces on the plate are cancelled out. The compacting mechanism can thereby go from a fully raised position as shown in
Of course, other compacting mechanisms operating on the same general principles are contemplated. For example, the compacting mechanism described above may have a moving plate that is raised or lower by a different mechanism than that of the screw actuator and drive mechanism described above, and the number and orientation of the linkages may be changed. For example, a ball actuator may be substituted for the screw actuator.
Another alternative embodiment may be described with reference to
Another alternative embodiment may be described with reference to
This embodiment illustrates that the drive system and the guide linkage system need not be integrated as they are in the preceding two embodiments. The drive system may be any suitable drive system such as the drive screw systems described above, a geared system, a hydraulic system or the like. The guide linkage system generally includes at least two linkages, where each linkages operates in a plane and where the planes of at least two of the guide linkages intersect. The planes, for example, may be normal to each other.
A control system (not shown) controls the operation of the trash compactor. The control system can take inputs such as whether the inlet door is open, how many times the inlet door has been opened, the time since the last operation of the compacting mechanism, the current draw of the motor and so forth to operate the trash compactor. One possible mode of operation involves operating the compacting mechanism after the inlet door has been opened a predetermined number of times. For example, after the inlet door has been opened seven times, the control system locks the inlet door shut and operates the compacting mechanism. The stroke length of the platen may be determined by how many times the compacting mechanism has been operated since the liner to the trash receptacle has been last changed, it might be operated until a predetermined amount of force has been applied to the trash by the platen, or it might have a fixed length unless a predetermined force level has been exceeded. Other operating modes may be programmed as desired.
The compacting mechanisms described herein may be suitable for other uses than in a trash compactor. Any application where force is applied evenly over a surface may be suitable. For example, the compacting mechanism may be suitable for use in a machine press or a printing press.
Various embodiments of the invention have now been described in detail. Since changes, alterations and additions to the above described embodiments may be made without departing from the nature, spirit or scope of the invention, the invention is not to be limited to the embodiments described above, but rather the scope of the invention is defined only by the appended claims.