Working Machine

Abstract

A working machine includes a support, and a moveable material handling assembly having a working arm mounted at a first pivot and configured to be mounted to a material handling implement at a second pivot. A pivoting mechanism is mounted to the implement at a third pivot and includes a Z bar link, a chassis link, and an actuator. The Z bar link mounts to the working arm at a fourth pivot and the chassis link mounts to the Z bar link at a fifth pivot and mounts to the support at a sixth pivot. The actuator is mounted to the Z bar link at a seventh pivot, and the fourth is pivot between the fifth and seventh pivots. The implement pivots relative to the working arm about the second pivot via pivoting the arm relative to the support about the first pivot.

1 . A working machine comprising a support, and a material handling assembly movable relative thereto, the material handling assembly comprising:
 a working arm pivotally mounted to the support at a first pivot, and configured to be pivotally mounted to a material handling implement, such as a shovel, at a second pivot; and   a pivoting mechanism configured to be pivotally mounted to the implement at a third pivot, and comprising:
 a Z bar link; 
 a chassis link; and 
 a first actuator operable to extend and retract, 
   the Z bar link pivotally mounted to the working arm at a fourth pivot,   the chassis link pivotally mounted to the Z bar link at a fifth pivot,   the chassis link pivotally mounted to the support at a sixth pivot, and   the first actuator pivotally mounted to the Z bar link at a seventh pivot,   wherein the fourth pivot is interposed between the fifth and seventh pivots,   wherein the pivoting mechanism is configured to pivot the implement relative to the working arm about the second pivot via pivoting of the working arm relative to the support about the first pivot, and via operation of the first actuator, and   wherein the pivoting mechanism is interposed (e.g. substantially centrally) between opposing lateral ends of the working arm.   
     
     
         2 . The working machine of  claim 1 , wherein a ratio of a distance between the fifth and seventh pivots to a distance between the fifth and sixth pivots is in the range of 1.69 to 2.30; optionally, wherein said ratio is in the range of 1.79 to 2.19; optionally, in the range of 1.89 to 2.09; for example approximately 2.0. 
     
     
         3 . The working machine of  claim 1 , where a ratio of a distance between the fourth and seventh pivots to a distance between the fifth and sixth pivots is in the range of 0.83 to 1.12; optionally, wherein said ratio of the distance between the fourth and seventh pivots to the distance between the fifth and sixth pivots is in the range of 0.87 to 1.07; optionally in the range of 0.92 to 1.02, for example approximately 1.0. 
     
     
         4 . The working machine of  claim 1 , wherein a ratio of a distance between the fourth and fifth pivots to a distance between the fifth and sixth pivots is in the range of 0.87 to 1.19; optionally, where said ratio of the distance between the fourth and fifth pivots to the distance between the fifth and sixth pivots is in the range of 0.93 to 1.13; optionally, in the range of 0.98 to 1.08, for example approximately 1.0. 
     
     
         5 . The working machine of  claim 1 , wherein a ratio of a distance between the first and sixth pivots to a distance between the fifth and sixth pivots is in the range of 0.93 to 1.27; optionally, wherein said ratio of the distance between the first and sixth pivots to the distance between the fifth and sixth pivots is in the range of 0.99 to 1.21; optionally, in the range of 1.05 to 1.16, for example approximately 1.1. 
     
     
         6 . The working machine of  claim 1 , wherein the first actuator is configured to be pivotally mounted to the implement or a further link of the pivoting mechanism at a further pivot, wherein a distance between said further pivot and the seventh pivot increases and decreases when the first actuator extends and retracts respectively, wherein a ratio of a minimum distance between said further pivot and the seventh pivot and a distance between the fifth and sixth pivots is in the range of 2.67 to 3.62; optionally, in the range of 2.83 to 3.46; optionally in the range of 2.99 to 3.30, for example approximately 3.1. 
     
     
         7 . The working machine of  claim 1 , wherein the first actuator is configured to be pivotally mounted to the implement or a further link of the pivoting mechanism at a further pivot, wherein a distance between said further pivot and the seventh pivot increases and decreases when the first actuator extends and retracts respectively, wherein a ratio of a maximum distance between said further pivot and the seventh pivot and a distance between the fifth and sixth pivots is in the range of 4.44 to 6.01; optionally, in the range of 4.70 to 5.75; optionally, in the range of 4.96 to 5.49, for example approximately 5.2. 
     
     
         8 . The working machine of  claim 1 , wherein the material handling assembly is configured such that a maximum dumping angle of the implement relative to a ground plane of the working machine at a maximum horizontal reach position of the second pivot is in the range of 50 to 80 degrees; optionally in the range of 60 to 75 degrees, for example approximately 70 degrees. 
     
     
         9 . The working machine of  claim 1 , wherein the material handling assembly is configured such that a maximum dumping angle of the implement relative to a ground plane of the working machine at a maximum lift position of the second pivot is in the range of 40 to 60 degrees; optionally, 45 to 55 degrees, for example approximately 50 degrees. 
     
     
         10 . The working machine of  claim 1 , wherein the material handling assembly is configured such that an overall maximum dumping angle of the implement relative to a ground plane of the working machine is in the range of 60 to 90 degrees; optionally, in the range of 70 to 85 degrees; optionally in the range of 80 to 85 degrees, for example, approximately 83 degrees. 
     
     
         11 . The working machine of  claim 1 , wherein the working arm comprises: two opposed longitudinal structural members; and
 a transverse connecting member connecting the structural members,   wherein the pivoting mechanism is supported by the connecting member, and   wherein a ratio of a distance between a longitudinal axis of the connecting member and the first pivot to a distance between the first and second pivots is in the range of 0.50 to 0.68; optionally in the range of 0.53 to 0.65; optionally, in the range of 0.56 to 0.62, for example approximately 0.59.   
     
     
         12 . The working machine of  claim 1 , wherein the working arm comprises:
 two opposed longitudinal structural members;   a transverse connecting member connecting the structural members; and   a first cantilever member projecting from the connecting member (e.g. substantially parallel to a longitudinal axis of the working arm),   wherein both structural members are pivotally mounted to the support at the first pivot, and configured to be pivotally mounted to the implement at the second pivot, and   wherein the first cantilever member is pivotally mounted to the Z bar link at the fourth pivot.   
     
     
         13 . The working machine of  claim 12 , wherein each structural member comprises a plate extending between the first and second pivots, and/or wherein the first cantilever member comprises a plate extending between the connecting member and the fourth pivot. 
     
     
         14 . The working machine of  claim 12 , wherein the working arm further comprises a second cantilever member projecting from the connecting member (e.g. substantially parallel to the longitudinal axis of the working arm), wherein the pivoting mechanism further comprises a tilt link and an implement link, the tilt link pivotally mounted to the second cantilever member at an eighth pivot, the tilt link pivotally mounted to the implement link at a ninth pivot, the implement link pivotally mounted to the first actuator at a tenth pivot, the implement link configured to be pivotally mounted to the implement at the third pivot, wherein extension and retraction of the first actuator respectively increases and decreases a distance between the seventh and tenth pivots so as to pivot the implement relative to the working arm about the second pivot, in use; optionally, wherein the second cantilever member comprises a plate extending between the connecting member and the eighth pivot. 
     
     
         15 . The working machine of  claim 1 , wherein the working machine comprises a hydraulic circuit comprising the first actuator and a supply of hydraulic fluid, wherein the first actuator comprises first and second ports in fluid communication with the supply of hydraulic fluid, and configured such that supply of fluid to the first port extends the first actuator such that fluid exits from the second port, and supply of fluid to the second port retracts the first actuator such that fluid exits from the first port, wherein the material handling assembly comprises a passage connected to the first and second ports so as to transport fluid from the second to the first port, in use, wherein the passage bypasses the supply of hydraulic fluid. 
     
     
         16 . The working machine of  claim 15 , wherein the passage comprises a one-way valve configured to allow fluid to move from the second port to the first port, and inhibit fluid moving from the first port to the second port, in use;
 optionally, wherein the working arm comprises two opposed longitudinal structural members, and a transverse connecting member connecting the structural members, and wherein the valve is mounted to the connecting member proximate to the first actuator.   
     
     
         17 . The working machine of  claim 1 , wherein the pivoting mechanism is configured to increase a crowding angle of the implement relative to a ground plane of the working machine when the working arm is pivoted about the first pivot so as to raise the second pivot relative to said ground plane, without operation of the first actuator, across 60% or more of a lifting range of the working arm; optionally, wherein the pivoting mechanism is configured to increase said crowding angle of the implement across 70% or more of the lifting range of the working arm; optionally, across 80% or more of the lifting range of the working arm. 
     
     
         18 . The working machine of  claim 1 , wherein, when the second pivot is at a minimum height above a ground plane of the working machine and the implement is at a corresponding maximum crowding angle, the pivoting mechanism is configured to increase the crowding angle of the implement relative to a ground plane of the working machine when the working arm is pivoted about the first pivot so as to raise the second pivot relative to said ground plane, without operation of the first actuator. 
     
     
         19 . The working machine of  claim 1 , wherein the working arm comprises one or more cavities spaced from any pivot; optionally, wherein the one or more cavities comprises at least one cavity extending substantially parallel to a pivot axis of the second pivot. 
     
     
         20 . The working machine of  claim 19 , wherein the working arm comprises two opposed longitudinal structural members, and a transverse connecting member connecting the structural members, and wherein the transverse connecting member comprises at least one of the one or more cavities; optionally, wherein an external surface of the connecting member comprises an opening proximate the first actuator, said opening leading to the at least one cavity in the connecting member.