Patent Publication Number: US-10316488-B2

Title: Universal backhoe coupler

Description:
FIELD OF THE INVENTION 
     The present invention relates to work machines such as tractor loader backhoe units, and more specifically to a universal bucket connector for such devices. 
     BACKGROUND OF THE INVENTION 
     A common work machine utilized in the construction field is a tractor loader backhoe which has a loader on the front of the tractor and a backhoe on the rear portion. There are a number of manufacturers of tractors for this purpose as well as bucket styles for the backhoe sections. The variety of equipment has generated a need for universal couplers designed to easily connect the tractor to the bucket of a backhoe assembly. The backhoe buckets are typically attached by a rear mounting pin which is received in a C-shaped slot which may be configured to accommodate a variety of rear pin types. Terms such as “rear”, “front”, “right”, etc. as used herein are from the operator&#39;s point of view—typically rearward—away from the loader portion. The front mounting pin configuration for the different bucket styles varies, in terms of pin diameter, spacing from the C-shaped slot, and in the lateral spacing or width of the flanges on the buckets. While a variation of diameter and distance from the C-shaped slot can be readily accommodated, it becomes much more difficult to adapt to a difference in lateral as well as longitudinal pin spacing. 
     One successful universal coupler for a backhoe assembly is shown in U.S. Pat. No. 9,284,712 wherein a first link is pivotally connected to the articulation joints of the backhoe assembly. Mounting holes for a first and third style bucket with equal lateral pin spacing are provided on the first link. A second link is connected to the first link and is pivotal between a first position in which the mounting holes are exposed and a second position in which the second link covers the holes on the first link and provides the mounting hole diameter and pin spacing for a bucket having a greater pin spacing. This coupler will accommodate either of two buckets of like pin spacing or a third bucket having a greater pin spacing. 
     What is needed in the art is additional versatility in accommodating backhoe buckets of varying pin spacing, mounting hole location and diameter. 
     SUMMARY OF THE INVENTION 
     In accordance with an aspect of the present invention, there is provided a coupler which accommodates buckets of differing pin location and diameter as well as a greater number of buckets of differing lateral pin spacing. 
     In accordance with another aspect of the present invention, there is provided a universal coupler for connecting multiple style buckets to the articulation joints of a single style work machine. The coupler has a pair of like multi-apertured outer side portions, a pair of like multi-apertured inner side portions partially spanned by the outer side portions, and a pair of like rearwardly extending slotted portions, each disposed laterally intermediate a corresponding outer side portion and inner side portion for receiving a rear bucket mounting pin. Each of a pair of pivotal spacers is disposed laterally intermediate a corresponding outer side portion and inner side portion. The spacers are pivotable between stowed positions and deployed positions aligned with a first pair of the inner side portion apertures for receiving apertured mounting flanges of a first style bucket and at least one front mounting pin. Lateral movement of the first style bucket is minimized by the interengagement of flange inner faces and the spacers. Further pairs of apertures of the inner side portions are positioned to be spanned by the mounting flanges of other style buckets. 
     In accordance with yet another aspect of the present invention, there is provided a work machine with mounting points for articulated movement of a bucket including a universal coupler for connecting multiple style buckets. The coupler has inner side portions with several longitudinally spaced apart pairs of apertures positioned to be spanned by the mounting flanges of several different style buckets all having mounting holes for receiving at least one front mounting pin. Lateral motion of certain style buckets is minimized by the interengagement of outer faces of the inner side portions of the coupler with inner faces of the bucket flanges. Lateral motion of other style buckets may be minimized by spacers interposed between the outer faces of the inner side portions and the inner faces of the bucket flanges. Lateral motion of further style buckets may be minimized by the interengagement of rearwardly extending rear mounting pin receiving slotted portions of the coupler with inner faces of the bucket flanges. 
     An advantage of the embodiment described herein is the optional use of non load bearing spacers incorporated in the design of the coupler to prevent side to side movement of the bucket on the coupler. 
     Another advantage is the embodiment described herein allows for spacers to be kept and stored on the coupler when not in use thereby insuring the correct spacers are used. 
     Yet another advantage is the embodiment described herein allows for the spacers to be rotated out of the way when not needed allowing additional clearance for alternate attachments. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of an exemplary embodiment of the invention taken in conjunction with the accompanying drawings, wherein: 
         FIG. 1  is a side elevation view of a portion of a backhoe assembly showing a work machine arm and first style bucket joined by a coupler according to an exemplary embodiment of the present invention; 
         FIG. 2  is an isometric view of a portion of the backhoe assembly of  FIG. 1  as seen from the dipper end; 
         FIG. 3  is an isometric view of the coupler of  FIGS. 1 and 2 ; 
         FIG. 4  is a side elevation view of the coupler from the right side of  FIG. 3 ; and 
         FIG. 5  is a side elevation view of a second style bucket joined with a work machine arm and the coupler of  FIGS. 3 and 4 . 
     
    
    
     Corresponding reference characters indicate corresponding parts throughout the several views. The exemplification set out herein illustrates one embodiment of the invention, in one form, and such exemplification is not to be construed as limiting the scope of the invention in any manner. 
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to the drawings, and more particularly to  FIG. 1 , there is shown a portion of a work machine  100  which generally includes a conventional articulated arm  110  pivotable under operator control through a limited range of angles about both a vertical axis and a horizontal axis. A first style bucket  120  is pivotally coupled to the free end of the arm  110  by a pivot pin  111  and coupler  130 . A dump link mechanism includes a hydraulic cylinder  112  which extends from near the base of the arm  110  to engage a link  113 . One end of link  113  is pivotally connected near the free end to the arm  110  and the other end is connected by a further link  114  to the coupler  130 . The bucket  120  and coupler  130  assembly is pivotable through a limited range of angles about the generally horizontal axis of the pivot pin  111  under operator control of the cylinder  112 . When the operator causes the piston rod to extend, link  113  is pivoted clockwise as viewed in  FIG. 1  causing link  114  to move downward and the bucket and coupler assembly pivots clockwise. Retracting the piston rod causes counter-clockwise bucket and coupler rotation. 
     A lever arm is formed by the separation between the pivotal connection at  111  and the pin  115  of link  114 . A longer lever arm and resulting greater force-less range of motion connection is achieved by moving the link  114  to be coupled by a pin passing through aperture  116  in the coupler  130 . Aperture  116  as well as several other apertures in the outer side portions may be provided with the illustrated bushings if desired. The bucket  120  has a rear mounting pin  121 , normally fixed to the bucket, which may be received in rearwardly opening C-shaped rear bucket pin slots  323  ( FIGS. 3 ) and  424  ( FIG. 4 ). The front mounting pin  122  may then be passed through both bucket flanges  221  and  222 , as well as the coupler  130  fixing the buck in position. 
     In  FIG. 2 , coupler  130  is formed as a pair of like multi-apertured outer side portions  231  and  241 , and a pair of like multi-apertured inner side portions  251  and  261  partially spanned by the outer side portions. There are also a pair of like rearwardly extending slotted portions  471  ( FIGS. 4 ) and  381  ( FIG. 3 ), each disposed laterally intermediate a corresponding outer side portion and inner side portion for receiving a rear mounting pin. For example, rearwardly extending portion  381  lies intermediate the outer surface or face  262  of inner portion  261  and the inner surface or face  242  of outer portion  241 , compare  FIGS. 2 and 3 . The pairs of outer, inner and rearwardly extending portions may be individual steel plates permanently joined by welding. The members of each pair are essentially identical or at least mirror images of one another. The coupler may also be formed of a lesser number of parts by casting, forging or other suitable techniques. 
       FIGS. 2 and 3 , a pair of like pivotal spacers  280  and  290  is disposed laterally intermediate corresponding outer side portions and inner side portions. The spacers are pivotable between stowed positions and deployed positions aligned with a first pair of apertures  252  (and a like hole in portion  261 ) of the inner side portion for receiving apertured mounting flanges of a first style bucket and at least one front mounting pin as shown in  FIGS. 1 and 2 . The spacers are pivotally held within the coupler by respective pivot support or hinge pins  281  and  291  passing through hinge portions  282  and  292 . As can be seen in  FIGS. 2 and 3 , hinge portion  282  fills a separation distance between inner side portion  251  and outer side portion  231 ; and likewise hinge portion  292  fills a separation distance between inner side portion  261  and outer side portion  241 . In  FIG. 3 , spacer  280  is shown in a stowed position while spacer  290  is deployed for filling the space between the inner face of flange  222  and the outer face  262  of inner portion  261 . As can be seen in  FIG. 3  spacers  280  and  290  are generally cylindrical having a cylindrical aperture therethrough and are coupled to hinge portions  282  and  292  respectively. Spacers are retained in either the deployed or the stowed position by locking or latching pins  283  and  293  which engage one of the two locking pin apertures  284  or  286 , and  294  or  296 . Lateral bucket movement is minimized by the interengagement of bucket flange inner faces and the spacers. 
       FIG. 4  is a right side elevation view of the coupler  130 . Aperture  432  is for receiving the pivotal pin  111 . Link  114  is connected by pin  115  to either aperture  434 , the maximum amplitude hole, or aperture  116 , the maximum power hole. Latching or lock pin aperture  286  receives locking pin  283  retaining the spacer  280  in the stowed position. In this configuration, latching hole  284  is unused. Apertured inner side portion  251  has two apertures  252  and  438 , each positioned relative to the rear bucket pin slot  424  for receiving the front mounting pin of a specific style bucket. 
     In  FIG. 5 , a second style bucket  600  is illustrated coupled to the work machine. Bucket  600  has a single pair of mounting flange such as  602  with the rear mounting pin  604  engaging slots  323  and  424 , and the front mounting pin  606  passing through aperture  438 . 
     The bucket  120  has the greatest transverse separation between mounting flange inner surfaces as well as the greatest longitudinal distance between front and rear mounting pin locations of the two bucket styles discussed. Lateral movement (slop) of bucket  120  is minimized by the spacers  280  and  290 . Bucket  600  has the least space between front and rear mounting pin locations and a separation between inner flange surfaces less than that of the other bucket style. This separation is compensated by bucket flange engagement with the outer surfaces of the rear portions  472  and  381 . 
     While this invention has been described with respect to at least one embodiment, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims.