Abstract:
A container handling mechanism suitable for mounting on the side of a refuse vehicle for loading material from refuse containers is disclosed that includes a lift assembly, having a pair of spaced, generally parallel lift support members, attachable to a refuse vehicle, a carriage device reciprocally operable along the lift support members of the lift assembly, a container grabbing system carried by the carriage device and further including a pair of opposed grabber fingers and an actuator system for closing and opening the grabber fingers to engage and release containers of interest, the container grabbing system being vertically pivotable on a short radius for adjusting the position of and tipping a container. A chain and cylinder drive system operates the carriage device along the lift assembly, and a control system controls operation of the container handling mechanism.

Description:
BACKGROUND OF THE INVENTION 
   I. Field of the Invention 
   The present invention relates generally to container handling equipment, including systems for accessing, grabbing, lifting and tipping a wide range of sizes and shapes of collection containers into charging hoppers or compartments of side loading collection vehicles, or other receptacles, and thereafter returning empty containers to their pickup locations. More particularly, the present invention relates to an automated container handling system including a container grabbing device, that is not only capable of lateral extension, but also capable of full lift and dump operation in very close quarters. A linearly-operating lift system is provided to lift and lower containers that cooperates with a pivoting, short-arm container grabbing device with hydraulic fingers. A rotary actuator pivots the grabbing device to adjust grabbing angle, tip containers and rotate it to and from a stowed position. 
   II. Related Art 
   Various vehicles dedicated to the collection of refuse or recyclables have included mechanized container handling devices that allow an operator to cause the device to access, lift, empty and return containers of interest without the need for any direct interaction by the operator so that the operator may remain in the vehicle. Such a holding or grabbing device is generally connected to an arm or extendable boom which is connected, in turn, to a base mounted on the vehicle. The arm or boom and grabbing device are operated in concert to access and engage a container of interest, lift and dump the container into a receiving hopper and return the empty container to the original location. One device of the class with an extensible boom is shown in U.S. Pat. No. 5,651,654 to Christenson and assigned to the same assignee as the present invention. Grabbing devices are also known which have opposed arms or fingers that converge around the girth of containers. Such devices generally have themselves been attached to extended arm members configured to pivot in a generally vertical plane to lift and invert a captured container and return it empty to an upright position. One such container grabbing device is illustrated and described in U.S. Pat. No. 5,769,592 to Christenson and also assigned to the same assignee as the present invention. 
   Systems also have been devised in which converging/diverging gripper arms are mounted on a carriage to reciprocate along a lift assembly using a chain drive or another mechanism. Such systems are disclosed in U.S. Pat. No. 5,230,393 and RE34,292. Another device is shown in U.S. Pat. No. 5,702,225 which depicts a pivoting linear lifting system operable along a pair of spaced rails. Curves in upper portions of the rails determine and control the tipping angle and radius for a captured container. 
   Mechanisms of known container handling devices generally have a large number of moving parts and articulated joints which are exposed to the extreme clogging and corrosive conditions of refuse collection, and, as such, tend to require frequent maintenance. It would thus be advantageous to provide a simplified mechanism to automatically operate the lift and dump arm function that reduces mechanism complexity and maintenance requirements. There is also a need to reduce the required lateral and/or vertical distance necessary for operation of such a lift and dump system so that an associated collection vehicle can successfully automate collection in narrower passages such as alleyways, or the like, in addition to emptying curb-side containers on wider streets. 
   SUMMARY OF THE INVENTION 
   By means of the present invention, there is provided a container handling or loading system, including a mechanism able to grab, lift and dump a relatively large range of sizes of refuse containers, which is particularly useful in loading refuse vehicles from the side in close quarters or narrow, confined spaces such as alleyways or the like. The container handling system of the present invention requires no more lateral distance to operate than that required for the truck to pass alongside a container of interest to be emptied. A container sandwiched between a passing truck and a wall, for example, can be automatically accessed, grabbed, lifted, dumped and returned to its original location where only minimum lateral clearance exists. The container handling mechanism of the invention also is one that can optionally move laterally with respect to a refuse truck for accessing, grabbing, lifting, dumping and returning a more laterally remote refuse container to its original location. 
   The system includes a pivoting lift frame assembly attachable to a refuse vehicle, a carriage device reciprocally operable along the lift frame assembly, a container grabbing and tipping system carried by the carriage device and further including a short radius rotational tipping mount and a pair of opening and converging opposed grabber arms or fingers. Operating or actuating systems operate the grabber arms and tipping mount to engage and tip a variety of sizes and shapes of containers. A carriage drive system is provided for operating the carriage device linearly along the lift assembly and a system of automatic controls is provided for controlling the operation of the container handling system. 
   The container lift frame assembly of the handling system as exemplified in the illustrative embodiment includes a top-pivoting, bottom-extending frame designed to be attached to a material receiving receptacle, in this case, a charging hopper of a side loading refuse vehicle. The frame includes a pair of spaced, generally parallel, side or lift support members spaced and connected by a common upper cross member. The cross member itself, in turn, spans, and is fixed to, a pair of generally vertically disposed telescoping support members designed to ride in vertical channels attached to, or integral with, the sidewall of an associated charging hopper or other receiving receptacle sought to be loaded by the container handling system of the invention. 
   The spaced lift support members are mounted so as to pivot in a generally vertical plane relative to the upper cross member and the lower portion of the lift support members are further pivotally attached to a bottom extending frame that includes a pair of spaced, generally parallel, laterally extendable members connected to advance and retract the lower portion of the lift support members thereby causing the upper ends of the lift support members to pivot and the vertical support members to telescope to accommodate the corresponding vertical displacement of frame members thereby accommodating the generally linear lateral displacement of the lower portions. In this manner, the associated container grabber can remain generally at the same height during lateral displacement. 
   A carriage system is mounted from the lift support members and carried by a drive system in a manner that enables it to traverse along the lift support members to accomplish a lifting function. The carriage system includes a rotary actuator having a double ended output including output shafts that carry and rotate spaced arm members of a yoke which, in turn, is fixed to a grabbing device for grabbing and releasing containers. The yoke mount enables the grabbing device to be pivoted or rotated generally vertically about a very short radius so as to rotate from a storage to a grabbing or deployed position in limited lateral space and also to adjust the posture of a grabbed container throughout a lift and dump cycle. The grabbing device is preferably one with opposed spaced fingers that close about a container during the grabbing function and open to release the container. The fingers are preferably operated by a compact, fully enclosed hydraulic actuating system that rotates spaced mounting shafts to open and close the fingers. The grabber fingers are designed to accommodate a wide range of container shapes and sizes. 
   The carriage is operated along the lift support members by a chain and cylinder mechanism that includes a pair of double-acting, double-ended hydraulic lift cylinders, each operating along a cylinder rod mounted along an associated lift support member in conjunction with a chain carried by sprockets mounted at the ends of each of the lift cylinders in coordinated fashion to operate the carriage and with it the grabber system along the lift support members to raise and lower a captured container. The rods are approximately twice the length of the cylinders. The carriage system is attached to mounts carried by the chains which are also fixed to the lift support members near the midpoints thereof in a manner that enables the carriage to travel the full length of the rods or lift support members or double the distance traveled by the lift cylinders as the chains also move the carriage a distance equal to that traveled by the cylinders. 

   
     BRIEF DESCRIPTION OF THE DRAWING 
     In the drawings, wherein like reference characters denote like parts throughout the same: 
       FIG. 1  is a rear elevational view partially in phantom of a side-loading vehicle equipped with the container handling system of the invention illustrating two steps in the lift and dump cycle including the accessing and dumping of a container in close quarters; 
       FIG. 2  is a view similar to that of  FIG. 1  showing the container handling system of the invention in lateral extension demonstrating two positions including the accessing and dumping of a container of interest located a lateral distance from the side of the vehicle; 
       FIGs. 3   a and  3   b  a chain and cylinder combination drive system associated with the raising and lowering of the carriage and grabber system along a side frame member in the equivalent of a fully lowered and fully raised position, respectively; 
       FIG. 4  is a greatly enlarged perspective view depicting a fully enclosed hydraulic actuating system for operating the fingers of a grabber suitable for use in the container handling system of the invention; 
       FIG. 5  is a fragmentary perspective view of a collection vehicle body with parts removed for clarity showing parts of a side loading receiving hopper equipped with a container handling system in accordance with the invention illustrating the container handling system in a fully retracted or stowed position; 
       FIG. 6  is a fragmentary perspective view of a collection vehicle body with parts removed for clarity equipped with a container handling system in accordance with the invention with the grabber lowered and rotated to a generally horizontal posture; 
       FIG. 7  is a view similar to  FIG. 6  showing the container handling system addressing the remote container; 
       FIG. 8  is a view similar to  FIGS. 6-7  showing the container being raised for emptying; 
       FIG. 9  is a view similar to  FIGS. 6-8  showing the container being tipped; and 
       FIG. 10  is a schematic perspective representation of a side loading refuse vehicle employing an embodiment of the present invention. 
   

   DETAILED DESCRIPTION 
   The container handling system of the present invention represents advances in the automated lifting and emptying of containers, particularly with regard to manipulating containers in close quarters and addressing a wide variety of container sizes and weights. The system enables the lifting and tipping of containers with little or no lateral room in a manner which also enables the containers to remain generally upright throughout the grabbing and lifting process until the final tipping. The system greatly reduces the need for lateral and vertical space associated the lift and tip operations. 
   The container handling system is able to handle containers in a wide range of sizes and shapes including large, heavy containers. For example, such a system handles anything from normal 34 gallon (129 liter) residential curb-side containers to much larger containers such as 300 gallon (1136 liter) containers weighing 1200 pounds (544.2 kg) or more. The entire operation of the system may be automated and micro-processor controlled. The detailed embodiment shown here is meant to illustrate the concepts of the invention and not to limit the scope in any manner. Variations will occur to those skilled in the art. 
     FIG. 1  depicts a rear elevational view partially in phantom of a side loading refuse truck denoted generally by the reference character  20  which represents one of several types of vehicles for which the container handling system of the present invention is particularly well suited. The vehicle includes a truck body  22  mounted on a truck chassis generally at  24 . The truck body  22  is of a rear discharge type including tailgate  26 , top hinged by a pair of hinges as at  28 . A container handling mechanism, in accordance with the invention is depicted generally at  30  and includes a container grabber mechanism generally at  32 . The grabber mechanism is shown in one position having grabbed and retrieved a container  34  and in a tipping position, shown in phantom, emptying the container  34  into a forward charging hopper of the truck body  22 . In  FIG. 1 , the container handling mechanism is depicted with the left frame in a fully upright or vertical posture, with the lower portion of the mechanism fully retracted. This enables operation in the narrowest of quarters, as it will be noted that a container as at  34  need simply be grabbed, lifted vertically and tipped. 
     FIG. 2  is a view similar to that of  FIG. 1  showing the container handling system of the invention in lateral extension accessing, or replacing, and tipping container  34  located a distance laterally away from the vehicle  20  with the tipping position again being shown in phantom. 
   The details of the container handling system  30  are best depicted in  FIGS. 2-10 . The system has a main frame that includes a pair of structural side or lift support members or structures  40  and  42  carried by an upper cross member in the form of a connecting bar  44 . As best seen in  FIGS. 8 and 9 , the lower portions of members  40  and  42  are pivotally connected at  46  and  48 , respectively, to a bottom extending frame that includes link members  50  and  52  which, in turn, are pivotally connected at  54  and  56  to a pair of spaced, generally parallel retractable lateral support structural members  58  and  60  which are generally horizontally mounted and designed to move laterally, generally parallel to the bottom  62  of the truck body  22  and are attached to be operated by an outer connecting cross member  64 . The bottom extending frame is reciprocally operated laterally by a cylinder  66  ( FIGS. 1 and 2 ) and rod  68  attached to member  64  as by a clevis or the like  70 . 
   The upper cross member  44  connects a pair of spaced parallel members  72  and  74  ( FIG. 6 ) which are telescopically engaged in respective generally vertical hollow shapes  76  and  78  abutting the structural sidewall  79  of the forward charging hopper of truck body  22 . This allows the upper end of the main frame to move and adjust in a generally vertical direction as needed with the lateral displacement of the grabber as will be described. 
   The carriage and grabber system includes a carriage device  80  that is mounted to travel along the length of structural lift support members  40  and  42  and includes a pair of housings that include plate box structures  82  and  84  and structure members  86  and  88  which support a double-ended or double-output shaft rotary actuator  90  therebetween. A lift operating system for raising and lowering the carriage system along the structural lift support members  40  and  42  is provided that includes a combination of two mechanisms, one carried by each support member, the details of which are best shown in  FIG. 3 . A pair of lift chain segments each having a fixed end and a traveling end and a double-acting fluid cylinder are associated with each support member  40 ,  42 . Thus, the mechanism includes a pair of double-acting, double-ended cylinders as at  92  mounted to travel along respective cylinder rods as at  96  which extend the length of structural lift support members  40  and  42 . As shown in  FIG. 3 , the upper and lower ends of cylinder rod  96  are connected between suitable heavy structural plates or gussets  100  and  102  fixed as at  104  and  106 . The cylinder  92  is moved along the cylinder rod  96  by hydraulic fluid supplied and drained through the rod in a well known manner. A pair of chain sprockets including an upper sprocket  108  and a lower sprocket  110  are mounted on the ends of cylinder  92 . Both sprockets are idler or freewheeling sprockets, and chain segments  111  and  112  are engaged around the sprockets. The chain segments  111  and  112  are connected at one end to a fixed member  114  and at the other end to a moving member  116 . The member  114  is fixed to the lift support member  40  and the member  116  is fixed to plate  86  which is part of box  82  of the assembly that carries one side of the carriage  80 . As the cylinder  92  moves upward, or downward, this configuration produces an additional equidistant movement of the chain segments  111  and  112  and with them the plate  86 , along the cylinder, causing the plate at  86  to move a distance along the member  40  twice that moved by the cylinder as illustrated in  FIG. 3 . With reference to both lift support members, of course, the carriage  80  will move double the distance moved by the cylinder. 
   The output shafts of the double-ended rotary actuator  90  of the carriage system  80  are connected to rotate relatively short, spaced arms of a heavy yoke device  120  ( FIGS. 6-9 ) which, in turn, is fixed to and carries grabber mechanism  122  which itself includes a totally enclosed, fluid-operated (preferably hydraulic) actuator  124  which operates a pair of opposed converging and diverging arms or grabber fingers  126  and  128  used to capture and release a container of interest. An enlarged view of the totally enclosed fluid-operated actuator  124  is shown in  FIG. 4  and includes a central gear case or housing  130  and a pair of rotating output shafts  132  and  134  which, in turn, are keyed to rotate and operate a pair of connector devices  136  and  138  which, in turn, are connected, respectively, to operate the grabber fingers  126  and  128  in a manner familiar to those skilled in the art. 
     FIGS. 5-9  further illustrate steps in a typical sequence of operating the container handling system of the invention which illustrate accessing, grabbing, lifting and tipping a collection container. Thus,  FIG. 5  depicts the illustrative embodiment of the container handling system of the invention in a fully stowed configuration with the gripper mechanism raised and rotated inward in a tipping posture. An alternate embodiment of the grabber fingers is shown at  126   a  and  128   a.  The bottom extending frame is fully retracted so that the system assumes a very narrow lateral profile abutting the side of the charging hopper of the truck body  22 . A container of interest  34  is shown at a lateral distance away from the container handling system in  FIG. 6 . The grabber mechanism is shown rotated into a forward generally horizontal grabbing posture prior to any lateral extension of the system toward container  34 .  FIG. 7  shows the bottom extending frame advanced with the grabber system having engaged and closed about the container  34  prior to raising of the container.  FIG. 8  shows the system with the lift operation completed and the carriage  80  at the top of the lift support members  40  and  42 . 
   It will be appreciated that the container  34  has been maintained in an upright position throughout the grabbing and lifting sequence and is positioned for tipping. The carriage has simply moved up the incline of the frame. In  FIG. 9 , the short-armed grabber yoke has been rotated to tip the container  34  and empty it into the charging hopper of the refuse truck. 
   Tipping having been completed, a simple reversal of the steps utilized to empty the container enables the container to be returned to the exact spot where it was picked up, because the bottom-extending frame has not moved from the pickup posture. The container handling system thereafter is returned to its stowed or traveling position. The design of the system of the invention, of course, results in a container handling system which, without the need for further motion or controls, at all times, returns a container being handled to its original spot. Of course, the system also works particularly well for close-in containers without the need to extend the bottom extending frame, as illustrated in  FIG. 1 , enabling the emptying of containers of interest in very close quarters wherein the container is simply grabbed and lifted vertically and tipped. 
   An important aspect of the container handling system of the invention involves in the ability of the system to unload containers in a wide variety of sizes. Thus, the system is designed to grab, lift and dump any container size between about 34 gallons (129 liters)and up to even very large and heavy containers up to about 300 gallons (1136 liters) weighing #1200 lbs (544.2 kg) or more with the grabber fingers enabled to seize a container in such a wide range of sizes without slipping or crushing. This is because the need for elongated arms or other cantilevered parts has been eliminated. While the system is able to grab, lift and dump containers of this wide range of sizes in narrow spaces like alleys, it may also reach such containers where the distance from the side of the truck to the center of the container is up to 8 feet (2.44 meters) or more in one model. The cycle time can be quite rapid for the container handling system of the invention inasmuch as there is no need to retract an arm (or the access and lift frame) in order to lift and invert the container or re-extend the arm (or the access and left frame) to return the container to its original site. 
     FIG. 10  shows a schematic perspective representation of a side loading refuse vehicle including an embodiment of the present invention in full lateral extension. This represents the lowest vertical position for unloading. 
   This invention has been described herein in considerable detail in order to comply with the patent statutes and to provide those skilled in the art with the information needed to apply the novel principles and to construct and use such specialized components as are required. However, it is to be understood that the invention can be carried out by specifically different equipment and devices, and that various modifications, both as to the equipment and operating procedures, can be accomplished without departing from the scope of the invention itself.