Abstract:
The addition of a thumb to a bucket of a work machine allows more uses for the work machine than having only the bucket. Having an attachment device locatable along the length of the stick permits different thumbs and different implement-positioning devices to be used with different work machines, adding more flexibility of use. The disclosed method and apparatus is for an attachment device for attaching an implement-positioning device to a load-bearing member, comprising a base member, a coupling member for adjustably attaching the base member to the load bearing member, and an attachment means for attaching the implement-positioning device to the coupling member.

Description:
TECHNICAL FIELD  
       [0001]     This invention relates generally to an apparatus and method for attaching an implement-positioning device at various positions along a load-bearing member.  
       BACKGROUND  
       [0002]     Work machines, such as backhoe loaders, excavators, or other similar work machines use counteracting thumbs and buckets to grasp, hold, and lift odd-shaped articles such as pipes, structural components, and the like, similar to the thumb of a human hand. When used to perform this secondary grasping, holding, or lifting function, a counteracting thumb is normally pivotally attached to a load-bearing member, lift arm assembly, or a bucket to accomplish the grasping, holding, and lifting function. An implement-positioning device, such as a hydraulic cylinder, is used to curl and uncurl the thumb to perform the grasping, holding, and lifting function. The hydraulic cylinder, in turn, is attached to a load-bearing member by means of an attachment device. Having the attachment device adjustably attachable at preselected locations along the load-bearing member permits different thumbs and different implements to be used with different work machines thereby increasing the versatility of the work machine.  
         [0003]     One known attachment device design is disclosed in U.S. Pat. No. 6,203,267 B1 that issued to Heiple et. al. on Mar. 20, 2001. It discloses a material handling assembly mountable on a stick of a work machine generally having a thumb pivotally attachable to the stick and cooperable with a bucket. The material handling assembly further includes a bracket mountable on the stick having a guideway therein, a strut received within and displaceable along the guideway, and a device for removably attaching the strut to the bracket at selected points along the length of the guideway. The adjustability of this design is limited. The material handling assembly is not able to increase the distance between the strut and the stick to adjust for different sized struts. And, the material handling assembly is bulky and can limit the rotational ability of the thumb.  
         [0004]     The present invention is directed to overcoming one or more of the problems as set forth above.  
       SUMMARY OF THE INVENTION  
       [0005]     In one aspect of the present invention, an attachment device for attaching an implement-positioning device to a load-bearing member comprises a base member, a coupling member for attaching the base member to the load-bearing member, and an attachment means for attaching the implement-positioning device to the coupling member.  
         [0006]     In another aspect of the present invention, a method for using an attachment device for attaching an implement-positioning device, having a cylinder end, to a load-bearing member, the attachment device comprising a base member and a coupling member for attaching the base member to the load-bearing member, comprises the steps of removing the coupling member, positioning the base member to a preselected location along the load-bearing member, and attaching the base member to the preselected location with the coupling member. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0007]     For a better understanding of the present invention, reference may be made to the accompanying drawings in which:  
         [0008]      FIG. 1  is a diagrammatic side view of an attachment device of the present invention adjustably attached to a stick of a work machine;  
         [0009]      FIG. 2  is a diagrammatic side view of an alternative embodiment of the attachment device of the present invention adjustably attached to the stick of the work machine; and  
         [0010]      FIG. 2   a  is a diagrammatic side view of an alternate embodiment of the separation device. 
     
    
     DETAILED DESCRIPTION  
       [0011]     Referring to the drawings, shown in  FIG. 1  is a load-bearing member such as a stick  100  of a work machine (not shown) having an end portion  103 . A pair of implements comprising, for exemplary purposes herein, a first implement or a bucket  112 , and a second implement or a thumb  115 , is pivotally attached in proximity to the end portion  103  of the stick  100  by means of a pin  118 . A linkage assembly  121  is pivotally attached to the thumb  115  by means of a pin  124  and is pivotally attached to the stick  100  by means of a pin  127 . Also shown is an implement-positioning device, such as a hydraulic cylinder  130 , having an aperture  131  and a rod end  133  pivotally attached to the linkage assembly  121  by means of a pin  139  such that the hydraulic cylinder  130  is operably attached to the thumb  115  for adjustably controlling the movement of the thumb  115 . In addition, the hydraulic cylinder  130  has a cylinder end  136  pivotally attached to an attachment device  142  of the present embodiment by means of a pin  145 . Although the implement-positioning device is shown herein as a hydraulic cylinder, the implement-positioning device may comprise other arrangements such as a strut, a tube, a bar, or other device.  
         [0012]     Referring further to  FIG. 1 , the attachment device  142  includes a coupling member such as a plate  151  that extends along the length of the stick  100  and is attached thereto by welding or by another suitable process and a plurality of mechanical fasteners such as bolts  163 . The plate  151  includes a first side  154  and a second side  157 . The first side  154  and the second side  157  each include a plurality of apertures, denoted as  160 , located at preselected locations along the plate  151 , and sized to receive the bolts  163 .  
         [0013]     The attachment device  142  further includes a base member  166  that is adjustably attached to the plate  151  and is locatable at a plurality of preselected locations along the plate  151 . The appropriate location of the preselected locations is effected by the size of the stick  100 , the size of the hydraulic cylinder  130 , the implement or implements used, and on which work machine the attachment device  142  is used, to name some factors. The base member  166  includes a first side  169  and a second side. Only the first side  169  is shown in  FIG. 1  as the first side  169  and second side are substantially identical. The first side  169  and second side each include a plurality of apertures, denoted as  175 , located such that each respective aperture  175  is substantially aligned with the corresponding aperture  160  of the plate  151  when the base member  166  is attached to the plate  151 .  
         [0014]     The attachment device  142  further includes an attachment means  178  attached to the base member  166  by welding or by another suitable process onto which the cylinder end  136  of the hydraulic cylinder  130  is pivotally attached. The attachment means  178  includes at least one flange, for exemplary purposes a first flange  181  and a second flange  182  are shown. Each such flange  181 ,  182  has a flange aperture therein, denoted as  184 , and each such flange aperture  184  has a boss, denoted as  187 , welded to each side thereof to reinforce the respective apertures  184 . The bosses  187  and the flange apertures  184  are sized so as to receive the pin  145 . It should be understood, however, that despite a pair of flanges  181 ,  182  being depicted in  FIG. 1 , any number of flanges could be used. It should also be understood that a bar, a linkage, a pin, a tube, a bracket, a post, a rod, or other such device could be used instead of the flanges  181 ,  182  to accomplish the present embodiment.  
         [0015]     Depicted in  FIG. 2  is an alternate embodiment of the attachment device denoted herein as  200 . For purposes of clarification, identical components used with the embodiments described herein shall be identified with like numbers. The attachment device  200  of  FIG. 2  includes a base member  206  having a top surface  207 , a coupling member  208 , and at least one separation device  210 . The attachment device  200  is infinitely attachable along the stick  100 . The base member  206  includes an attachment means  178  substantially illustrated and described previously with respect to the previous embodiment and again used to pivotally attach the hydraulic cylinder  130  to the base member  206 .  
         [0016]     Referring further to  FIG. 2 , the at least one separation device  210  of the present embodiment includes a plurality of wedges, denoted as  212 , having an end portion  213  and a plurality of mechanical fasteners, such as bolts  215  and nuts  216 , each bolt  215  having an end portion  217 . The nut  216  is sized so as to engage the end portion  217  of the bolt  215 . Further, each wedge  212  is locatable between the base member  206  and the stick  100  for adjusting the distance between the cylinder end  136  of the hydraulic cylinder  130  and the stick  100 . For exemplary purposes herein, four wedges  212  and four bots  215  and nuts  216  are shown being utilized with the embodiment described herein. It should be understood, however, that any number of wedges  212  and bolts  215  and nuts  216  could be used to achieve similar results. Additionally, it should be understood that the separation device  210  or any portion thereof, including the wedge  212  that may be set on top of another wedge  212 , could be attached to the base member  206 .  
         [0017]     For the present embodiment described herein, each wedge  212  includes an aperture  227  that is sized such that the aperture  227  is larger than the diameter of the bolt  215  so that the bolt  215  can float up and down in the aperture  227  when it is inserted therein as necessary to set the appropriate thickness of the separation device  210 . In order to set the appropriate thickness of the separation device  210  to achieve the desired distance between the base member  206  and the stick  100 , two wedges  212  are set on top of each other, the bolt  215  is inserted through the apertures  227  of the wedges  212 , and the end portion  217  of the bolt  215  is inserted into the nut  216 . The bolt  215  is then threaded at the end portion  213  of the wedge  212  tighter on the nut  216  drawing the bolt  215  through the nut  216  thus drawing the two wedges  212  together so that the combined thickness of the wedges  212  increases as the bolt  215  is tightened on the nut  216 . As the wedges  212  are drawn together the bolt  215  is allowed to float in the apertures  227  due to the apertures  227  being oversized, and thus allowing the wedges  212  to move up on each other. Finally, each wedge  212  includes threaded aperture  233 , shown in hidden detail. Each such aperture  233  is offset from aperture  227  in the wedges  212  so that the bolts  215  do not intersect aperture  233  when inserted therein.  
         [0018]     Alternatively, as depicted in  FIG. 2   a , the separation device  210   a  includes a plurality of wedges  212   a  having a first-end portion  213   a  and a second-end portion  214   a , a plurality of mechanical fasteners such as bolts  215   a , and a plurality of bars  220   a  (one shown), having threaded apertures therein (not shown). The first-end portion  213   a  of the wedges  212   a  includes apertures  227   a  sized to receive the bolt  215   a  and the second-end portion  214   a  includes apertures  229   a  sized to receive the bar  220   a . One bar  220   a  is inserted in the apertures  229   a  of two wedges  212   a  so as to connect the wedges  212   a  together. The bolts  215   a  are then inserted in the apertures  227   a  and threaded into the apertures in the bars  220   a . In order to set the appropriate thickness of the separation device  210   a , the wedges  212   a  are set on top of each other, the bolts  215   a  are tightened and the bolts  215   a  pull the wedges  212   a  toward the bar  220   a  and as such draws the wedges  212   a  together so that the combined thickness of the wedges  212   a  increases as the bolt  215   a  is tightened on the bar  220   a . This increases the distance between the base member  206   a  and the stick  100 .  
         [0019]     Depicted in  FIG. 2 , the coupling member  208  of the present embodiment comprises a first clamp  239  and a second clamp  240  each of which are used to adjustably attach the base member  206  to the stick  100 . It should be understood that although two clamps are shown, any number of clamps could be used to enable the present embodiment. Each clamp  239 ,  240  includes top portions  242 ,  243  and bottom portions  245 ,  246 , respectively. Additionally, each clamp  239 ,  240  includes at least one aperture  250 . It should be understood that any number of apertures could be provided in the clamps  239 ,  240  to achieve similar results. Each aperture  250  is sized to receive a mechanical fastener, such as bolt  256 , which is placed through the clamps  239 ,  240  and is threaded into the apertures  233  of the wedges  212 . It should be understood, however, that although bolts are depicted in  FIG. 2  as the mechanical fasteners, any suitable means to removably attach the wedges  212  together and/or removably attach the clamps  239 ,  240  to the wedges  212  could be used.  
         [0020]     Finally, the stick  100  includes side plates  259 ,  260  and a bottom plate  265  having respective side edges  266 ,  268  each of which extend a predetermined distance beyond the respective side plates  259 ,  260  of the stick  100 . The base member  206  is adjustably attached to the stick by positioning the wedges  212  between the base member  206  and the stick  100  and setting the appropriate thickness thereof so that the top portions  242 ,  243  of the clamps  239 ,  240  engage the side edges  266 ,  268  of the bottom plate  265  and the bottom portions  245 ,  246  of the clamps  239 ,  240  engage the top surface  207  of the base member  206  to create the required normal force so as to prevent the base member  206  from slipping from the preselected location along the stick  100 . To further prevent the clamps  239 ,  240  from slipping, the bolts  256  are placed through the apertures  250  in the clamps  239 ,  240  and threaded into the aperture  233  in the wedges  212 .  
         [heading-0021]     Industrial Applicability  
         [0022]     Work machines, such as excavators and backhoe loaders, are very expensive to purchase. It is, therefore, beneficial for an operator of such work machines to be able to use additional attachments with the work machines to perform additional operations. For example, thumbs are often used in conjunction with buckets to create a gripper, grapple, or the like to lift and carry odd-shaped items such as logs, pipes, and load-bearing components. An implement-positioning device such as a hydraulic cylinder is normally used to curl and uncurl the thumb to perform grasping, holding, and lifting functions. In the present invention, the implement-positioning device, depicted as the hydraulic cylinder  130  is attached to the stick  100  by an attachment device  142 ,  200 . The present invention provides for an attachment device  142 ,  200  that permits the hydraulic cylinder  130  to be adjustably attached to stick  100  of the work machine so as to adjustably control movement of the thumb  115 .  
         [0023]     In the first embodiment depicted in  FIG. 1 , the base member  166  is locatable at preselected locations along the stick  100  thereby allowing for different attachment locations of the hydraulic cylinder  130  to the stick  100 . In order to reposition the base member  166 , the bolts  163  are loosened and removed; the base member  166  is repositioned to a desired location, and then bolted in place by bolts  163 . The hydraulic cylinder  130  is then pivotally attached to the attachment means  178  by concentrically aligning the aperture  131  of the hydraulic cylinder  130  with the aperture  184  of the flanges  181 ,  182  and inserting the pin  145  therethrough.  
         [0024]     To reposition the base member  206  in the alternative embodiment depicted in  FIG. 2 , the bolts  236  on the clamps  239 ,  240  are removed and the clamps  239 ,  240 , wedges  212 , and the base member  206  are repositioned to the desired location. The top portions  242 ,  243  of the clamps  239 ,  240  are positioned on the side edges  266 ,  268  of the bottom plate  265  and the bottom portions  245 ,  246  of the clamps  239 ,  240  are positioned on the top surface  207  of the base member  206 . The wedges  212  are positioned between the base member  206  and the stick  100 , adjacent the clamps  239 ,  240 . Once the wedges  212  are in position, the appropriate thickness is set by applying pressure to the end portion  213  of the wedge  212  by threading the bolts  215  on the nuts  216  so that end portions  217  of the bolts  215  are drawn through the nuts  216 . This will cause the wedges  212  to be drawn together to increase their thickness to create the required normal force so as to prevent the base member  206  from slipping. The bolts  256  are then placed through the apertures  250  in the clamps  239 ,  240  and are threaded into aperture  233  in the wedges  212  tightening further the attachment device  200  to the stick  100 . The hydraulic cylinder  130  is then pivotally attached to the attachment means  178  described previously with respect to the previous embodiment. As should be appreciated by those of ordinary skill in such art, the provision of the clamps  239 ,  240  and wedges  212  allows for vertical and lateral adjustability of the attachment point of the hydraulic cylinder  130  to the stick  100 . This embodiment allows the attachment arrangement  200  to be removed from the stick  100  when needed by removing the bolts  256  and removing the clamps  239 ,  240 , the wedges  212 , and the base member  206 .  
         [0025]     Other aspects, objects and advantages of the invention could be obtained from a study of the drawings, the disclosure and the appended claims.