Abstract:
A container grabbing device is disclosed which utilizes a rotary actuator to open and close opposed converging fingers of the grabber in which the actuator has reversing counter-rotating, in-line opposed output shafts, one of which is used to operate each finger.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    I. Field of the Invention  
           [0002]    The present invention relates generally to vehicle-mounted container handling devices for grabbing, lifting and tipping (unloading) refuse and/or recyclables from collection containers into charging compartments of collection vehicles. More particularly, this invention relates to a grabbing device that may be attached to a swivel-mounted articulated arm carried on a side loading collection vehicle which allows containers of various shapes and sizes to be efficiently handled during collection efforts. With even further particularity, the present invention involves a concept for using a hydraulic rotary actuator to operate the converging fingers of a grabber device for capturing and releasing a container to empty the container into a charging hopper of a refuse packer collection vehicle.  
           [0003]    II. Related Art  
           [0004]    It is known to provide gripper or grabbing mechanisms employing opposed converging and diverging fingers to grasp, lift and tip refuse containers of various shapes and sizes. Such mechanisms have traditionally been mechanically rather complex devices which have included a plurality of articulated joints and one or more hydraulic cylinder-type linear operators to open and close converging opposed mechanized arm members or fingers. The arm members have been individually controlled or coordinated by using meshing gears, one associated with each of the fingers. In operation, the opposed arms have been caused to converge about a container with considerable force by the operation of relatively high pressure hydraulic cylinders which, while not a problem for handling rigid containers, could be excessive with respect to containers of softer sided polymeric material. In addition, the hydraulic cylinders need to be pivotally mounted and if meshing gears are used to coordinate the finger operation, these must be kept free of debris as must the pivot joints of the grabber fingers themselves. It will thus be appreciated that these previous designs generally have had a large number of exposed moving parts and exposed joints which have been subject to rapid wear, corrosion and contamination by the incursion of foreign material, all of which contribute to making such devices prone to requiring frequent repairs and replacement of parts.  
           [0005]    Concern with contamination by foreign materials is a particular problem in the collection, transportation and landfill ejection of refuse in which the grabbers continually face a less than ideal operating environment where debris can cause excessive wear and even cause the grabber device to jam and pivot joints or gears to freeze or otherwise become obstructed.  
           [0006]    Thus, there remains a need to reduce the required number of exposed moving parts in such devices in order to increase operating life and reduce maintenance frequency.  
         SUMMARY OF THE INVENTION  
         [0007]    In accordance with the present invention, there is provided a grabbing or gripping device employing converging finger members which is of a simplified mechanical construction and enjoys improved operating characteristics. The system utilizes a rotary actuator to open and close opposed converging fingers of the grabber which includes an actuator having reversing counter-rotating in-line opposed output shafts, one of which is used to operate each of a pair of shaped converging fingers. The device eliminates problems associated with linear operating cylinders and pivotal cylinder in-line mounting devices. In this manner, the use of the hydraulic rotary actuator eliminates a number of shafts, bearings, bushings and cylinders themselves. These are replaced by a single lighter weight substantially sealed or unexposed operating device.  
           [0008]    In addition, the rotary actuator further enables the provision of a constant clamping torque which can be set to protect the damageable parts of the grabber system and also the containers which are being grabbed, emptied and replaced at curbside or other places. This clamping or grabbing torque, while constant at one setting, can also be adjusted using controls as collection endeavors require. This enables adjustments for plastic or metal containers to be readily made. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0009]    In the drawings wherein like reference characters depict like parts throughout the same:  
         [0010]    [0010]FIG. 1 is a side elevational view of a refuse collection vehicle equipped with a grabber device according to the invention;  
         [0011]    [0011]FIG. 2 is a top view of the refuse collection vehicle of the type shown in FIG. 1 with the grabber device of the invention shown in both the fully open and container grabbing positions;  
         [0012]    [0012]FIG. 3 is a cross-sectional view of the collection vehicle taken substantially along lines  3 - 3  of FIG. 1;  
         [0013]    [0013]FIG. 4 a  is a plan view of the grabber mechanism of the invention in the closed or container grabbing position;  
         [0014]    [0014]FIG. 4 b  is a plan view of the grabber mechanism of FIG. 4 a  shown in the fully retracted or fully open position;  
         [0015]    [0015]FIG. 5 is a side elevational view depicting a grabber system of the invention engaging a typical refuse container for pick up and tipping; and  
         [0016]    [0016]FIG. 6 is an elevational view of the grabber mechanism of FIGS. 4 a ,  4   b  and  5 . 
     
    
     DETAILED DESCRIPTION  
       [0017]    The invention will be described in detail with respect to one or more embodiments which are presented as examples to illustrate the principles of the invention, but are not intended to limit the scope of the inventive concept in any manner. It is believed that variations will occur to those skilled in the art which will also fall within the confines of the inventive concept.  
         [0018]    We will refer first to FIGS.  1 - 3  where a grabber system in accordance with the invention is illustrated as part of a collection system including an articulated arm and is depicted generally at  10  and shown mounted to the chassis or frame  12  of a side loading collection vehicle  14 . The container handling system  10  includes a swivel mount  16 , articulated arm  18  and the gripping mechanism or grabber is depicted generally at  20 . A swivel mount  16  is attached to the chassis  12  next to a recess and a refuse receiving and charging hopper  22  which includes a top opening  24  for receiving recyclables and/or refuse.  
         [0019]    The articulated arm  18  is pivotally connected to the swivel mount  16  at one end and to the grabber  20  at the other end. The swivel mount  16  enables the position of the articulated arm  18  and grabber  20  to be adjusted back and forth along the length of the collection vehicle  14  to accommodate the position of a container of interest which need not be directly abreast of the grabber  20 . The grabber  20  and articulated arm  18  cooperate to empty selected containers into the charging hopper  22  through opening  24 . As stated, the collection vehicle  14  need not be aligned with the container of interest for grabbing and tipping.  
         [0020]    The refuse vehicle  14  includes the usual cab  26  and wheels  28  which carry a storage body  30  connected to the charging hopper  22 . Storage body  30  includes a tailgate  32  which is pivotally attached by a pair of vertically displaceable hinges  34  mounted at the top of the storage body  30 . The tailgate  32  is operated between an open and a closed position by a pair of hydraulic cylinders, one of which is shown at  36 , which are pivotally attached to the tailgate  32 , as at  38 , and to the storage body  30 , as at  40 .  
         [0021]    Side latches  42  are provided for latching the tailgate  32  to the storage body  30  in a well known manner. The storage body is designed to tilt in conjunction with the opening of the tailgate to discharge refuse. Tilting is accomplished by a pair of side-mounted hydraulic lift cylinders, one of which is shown at  44 , that are pivotally attached to the frame by structural members  46 , as at  48 , into the storage body  30 , as at  50 .  
         [0022]    The swivel mount  16  and articulated arm  18  are described in greater detail in U.S. Pat. No. 5,720,589, which illustrates and describes a swivel mount and articulated arm of the class suitable for use with the grabber mechanism of the present invention. That entire disclosure may be deemed incorporated herein by reference for any purpose. In general, however, the articulated arm  18  includes a pair of connecting, generally vertically pivotal articulated members, including a first or inner lift arm member  60  pivotally attached to the swivel mount  16  and a second or outer lift arm member  62  pivotally attached to the first lift arm member  60  at a joint  64 . A support member  78  (FIG. 5) or frame  80  of the gripping mechanism or grabber  20  is then pivotally attached to the outer lift arm member  62 , as at  66 . The articulated arm  18  may be operated by hydraulic cylinders as at  68  and  70  to extend the arm  18  to accommodate grabbing a container of interest and lifting and dumping the container into the refuse charging hopper  22 . Of course, the lift arm  18  is not limited to the embodiment shown and that is considered merely exemplary and may be any suitable lift arm mechanism attached to the swivel mount  16 .  
         [0023]    [0023]FIG. 4 a  is a plan view showing the grabber mechanism  20  in the closed or container grabbing position and FIG. 4 b  depicts the grabber arm in the fully open, retracted position utilized for allowing it to rest within the confines of the width of the collection vehicle  14  as also shown in FIG. 2. The grabber mechanism includes grabber fingers  100  and  102 . As best seen in FIGS. 5 and 6, the grabber fingers  100  and  102  are compound structures including respective base members  104  and  106 . Finger  100  further includes a tip segment  108  equipped with a rotatably mounted guide roller  110 ; likewise, finger  102  includes a pair of spaced tip segments  112  and  114 , respectively, carrying rotatably mounted guide rollers  116  and  118 . As noted in FIGS. 4 a  and  5 , the tip segment  108  is received between tip segments  112  and  114  in the gripping position with the fingers  100  and  102  closed about a container as at  120 .  
         [0024]    As best seen in FIGS. 5 and 6, the compound fingers  100  and  102  are operated by a single, central rotary actuator device  122 , which includes in-line, counter-rotating output shafts  124  and  126 , which are designed to rotate in opposite directions when the device is energized. The compound finger  100  is keyed to pivot with rotation of the shaft  124  of rotary actuator  122  and the opposed compound finger  102  is keyed to pivot with rotation of the shaft  126  of the rotary actuator  122  such that the activation of the device  122  will cause counter-rotating shafts  124  and  126  to cause the fingers  100  and  102  to converge or diverge as desired.  
         [0025]    The rotary actuator mechanism  122  is equipped with an adjustable variable output torque setting so that the force produced by the converging fingers  100  and  102  against a container as at  120  can be adjusted as necessary, depending on the type of containers being handled. Such a device is believed available from manufacturers such as Helac Corporation of Enumclaw, Wash.  
         [0026]    As can be seen from the foregoing, the only mechanically actuated part associated with the grabber system of the invention is the counter-rotating actuator system for opening and closing the compound fingers  100  and  102 . The only other mechanically moving and rotating devices are the guide rollers  110 ,  116  and  118  associated with the compound fingers  100  and  102 . This greatly simplifies the construction and increases the reliability of the grabber mechanism, reducing both wear and maintenance factors.  
         [0027]    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.