Work Tool Coupler Engagement System

Abstract

A coupling device may include a coupler frame a variable length actuator having a right actuator end and a left actuator end supported by the coupler frame and extending between the ends of the coupler frame. Right and left latches are slidably engaged by and movable relative to the coupler frame and are operatively connected to the ends of the variable length actuator. The variable length actuator operates to move between retracted and extended positions and may be slidably mounted on the coupler frame so that ends move horizontally relative to the coupler frame and the variable length actuator does not move vertically relative to the coupler frame. The latches move relative to the coupler frame between unlocked and locked positions as the variable length actuator moves between the actuator retracted and extended positions, respectively.

What is claimed is: 
     
         1 . A coupling device for coupling an implement to a machine, comprising:
 a coupler frame having a right frame end and a left frame end;   a variable length actuator having a right actuator end and a left actuator end and extending between the right frame end and the left frame end of the coupler frame, the variable length actuator being operable to move between an actuator retracted position and an actuator extended position and being slidably mounted on the coupler frame so that the right actuator end and the left actuator end move horizontally relative to the coupler frame and the variable length actuator does not move vertically relative to the coupler frame as the variable length actuator moves between the actuator retracted position and the actuator extended position;   a right latch slidably engaged by and movable relative to the coupler frame proximate the right frame end and operatively connected to the right actuator end of the variable length actuator; and   a left latch slidably engaged by and movable relative to the coupler frame proximate the left frame end and operatively connected to the left actuator end of the variable length actuator,   wherein the right latch and the left latch move relative to the coupler frame between a latch unlocked position that will not engage the implement when the variable length actuator is in the actuator retracted position and a latch locked position that will engage the implement when the variable length actuator is in the actuator extended position.   
     
     
         2 . The coupling device of  claim 1 , wherein the coupler frame comprises:
 a right horizontal guide slot operatively connected to the right actuator end to cause the right actuator end to move horizontally relative to the coupler frame and to prevent the right actuator end from moving vertically relative to the coupler frame; and   a left horizontal guide slot operatively connected to the left actuator end to cause the left actuator end to move horizontally relative to the coupler frame and to prevent the left actuator end from moving vertically relative to the coupler frame.   
     
     
         3 . The coupling device of  claim 1 , wherein the coupler frame comprises an actuator housing enclosing the variable length actuator and having a right horizontal guide slot and a left horizontal guide slot, wherein the variable length actuator comprises a right guide pin connected to the right actuator end and extending through the right horizontal guide slot and a left guide pin connected to the left actuator end and extending through the left horizontal guide slot, and wherein the right horizontal guide slot and the left horizontal guide slot engage the right guide pin and the left guide pin, respectively, to cause the right actuator end and the left actuator end to move horizontally relative to the coupler frame and to prevent the right actuator end and the left actuator end from moving vertically relative to the coupler frame. 
     
     
         4 . The coupling device of  claim 3 , wherein the right horizontal guide slot and the left horizontal guide slot extend through a housing rear wall of the actuator housing so that the right guide pin and the left guide pin are visible from a position external to the coupling device to provide an operator of the machine with a visual indication of a current position of the variable length actuator between the actuator retracted position with the right latch and the left latch in the latch unlocked position and the actuator extended position with the right latch and the left latch in the latch locked position. 
     
     
         5 . The coupling device of  claim 1 , wherein the variable length actuator is an extendable shaft assembly comprising:
 a motor wherein the left actuator end is a left motor end operatively connected to the left latch; and   a shaft extending from a right motor end of the motor and wherein the right actuator end is a right shaft end operatively connected to the right latch,   wherein the motor is actuatable to retract the shaft to move the extendable shaft assembly to the actuator retracted position and to extend the shaft to move the extendable shaft assembly to the actuator extended position.   
     
     
         6 . The coupling device of  claim 1 , comprising:
 a right linkage assembly operatively connecting the right actuator end to the right latch, the right linkage assembly comprising:
 a right lever pivotally mounted to the coupler frame proximate the right frame end, 
 a right actuator link pivotally connected between the right actuator end and the right lever, and 
 a right latch link pivotally connected between the right latch and the right lever; and 
   a left linkage assembly operatively connecting the left actuator end to the left latch, the left linkage assembly comprising:
 a left lever pivotally mounted to the coupler frame proximate the left frame end, 
 a left actuator link pivotally connected between the left actuator end and the left lever, and 
   a left latch link pivotally connected between the left latch and the left lever.   
     
     
         7 . The coupling device of  claim 6 , wherein the right linkage assembly comprises a right spring disposed between the right latch and the right lever and biasing the right latch away from the right lever, and wherein the left linkage assembly comprises a left spring disposed between the left latch and the left lever and biasing the left latch away from the left lever. 
     
     
         8 . The coupling device of  claim 6 , wherein the left actuator link comprises an engagement slot configured to receive a prying tool for manipulation of positions of the variable length actuator, the right linkage assembly, the left linkage assembly, the right latch and the left latch. 
     
     
         9 . A method of coupling and decoupling an implement to and from a machine having a coupling device connected to lift arms of the machine, the method of coupling and decoupling comprising:
 moving the machine toward the implement and engaging an implement rear wall of the implement with a coupler frame front wall of a coupler frame;   moving the coupling device to cause an implement engaging edge of the coupling device to be inserted into a coupler receiving bracket of the implement; and   actuating a variable length actuator to extend to an actuator extended position and to correspondingly cause a right latch and a left latch operatively coupled to the variable length actuator to move to a latch locked position with the right latch and the left latch disposed within latch receiving openings of the implement, wherein the variable length actuator is operable to move between an actuator retracted position and the actuator extended position and is slidably mounted on the coupler frame so that a right actuator end and a left actuator end of the variable length actuator move horizontally relative to the coupler frame, and the variable length actuator does not move vertically relative to the coupler frame as the variable length actuator moves between the actuator retracted position and the actuator extended position.   
     
     
         10 . The method of coupling and decoupling of  claim 9 , comprising displaying a visual indication at the coupling device of an actuator position of the variable length actuator and a corresponding latch position of the right latch and the left latch. 
     
     
         11 . The method of coupling and decoupling of  claim 10 , wherein the coupler frame includes a coupler rear wall having a right horizontal guide slot and a left horizontal guide slot, wherein the variable length actuator comprises a right guide pin connected to the right actuator end and extending through the right horizontal guide slot and a left guide pin connected to the left actuator end and extending through the left horizontal guide slot, wherein the right horizontal guide slot and the left horizontal guide slot engage the right guide pin and the left guide pin, respectively, to cause the right actuator end and the left actuator end to move horizontally relative to the coupler frame and to prevent the variable length actuator from moving vertically relative to the coupler frame, and wherein the visual indication of the actuator position and the corresponding latch position is provided by pin positions of the right guide pin and the left guide pin within the right horizontal guide slot and the left horizontal guide slot. 
     
     
         12 . The method of coupling and decoupling of  claim 9 , wherein the variable length actuator is an extendable shaft assembly having a motor wherein the left actuator end is a left motor end operatively connected to the left latch, and a shaft extending from a right motor end of the motor and wherein the right actuator end is a right shaft end operatively connected to the right latch, and wherein actuating the variable length actuator comprises actuating the motor to extend the shaft to move the extendable shaft assembly to the actuator extended position. 
     
     
         13 . The method of coupling and decoupling of  claim 9 , comprising:
 to decouple the implement from the machine, actuating the variable length actuator to retract to the actuator retracted position and to correspondingly cause the right latch and the left latch to move to a latch unlocked position with the right latch and the left latch withdrawn from the latch receiving openings of the implement; and   moving the coupling device to cause the implement engaging edge of the coupling device to move out of the coupler receiving bracket of the implement.   
     
     
         14 . A machine comprising:
 a cab;   a right lift arm;   a left lift arm;   a coupler frame having a right frame end with the right lift arm coupled thereto and a left frame end with the left lift arm coupled thereto;   a variable length actuator having a right actuator end and a left actuator end and extending between the right frame end and the left frame end of the coupler frame, the variable length actuator being operable to move between an actuator retracted position and an actuator extended position and being slidably mounted on the coupler frame so that the right actuator end and the left actuator end move horizontally relative to the coupler frame and the variable length actuator does not move vertically relative to the coupler frame as the variable length actuator moves between the actuator retracted position and the actuator extended position;   a right latch slidably engaged by and movable relative to the coupler frame proximate the right frame end and operatively connected to the right actuator end of the variable length actuator;   a left latch slidably engaged by and movable relative to the coupler frame proximate the left frame end and operatively connected to the left actuator end of the variable length actuator; and   an implement having an implement rear wall engaged by a coupler frame front wall when the implement is coupled to the machine,   wherein the right latch and the left latch move relative to the coupler frame between a latch unlocked position that will not engage the implement when the variable length actuator is in the actuator retracted position and a latch locked position that will engage the implement when the variable length actuator is in the actuator extended position.   
     
     
         15 . The machine of  claim 14 , wherein the coupler frame comprises:
 a right horizontal guide slot operatively connected to the right actuator end to cause the right actuator end to move horizontally relative to the coupler frame and to prevent the right actuator end from moving vertically relative to the coupler frame; and   a left horizontal guide slot operatively connected to the left actuator end to cause the left actuator end to move horizontally relative to the coupler frame and to prevent the left actuator end from moving vertically relative to the coupler frame.   
     
     
         16 . The machine of  claim 14 , wherein the coupler frame comprises an actuator housing enclosing the variable length actuator and having a right horizontal guide slot and a left horizontal guide slot, wherein the variable length actuator comprises a right guide pin connected to the right actuator end and extending through the right horizontal guide slot and a left guide pin connected to the left actuator end and extending through the left horizontal guide slot, and wherein the right horizontal guide slot and the left horizontal guide slot engage the right guide pin and the left guide pin, respectively, to cause the right actuator end and the left actuator end to move horizontally relative to the coupler frame and to prevent the right actuator end and the left actuator end from moving vertically relative to the coupler frame. 
     
     
         17 . The machine of  claim 16 , wherein the right horizontal guide slot and the left horizontal guide slot extend through a housing rear wall of the actuator housing so that the right guide pin and the left guide pin are visible from the cab to provide an operator of the machine with a visual indication of a current position of the variable length actuator between the actuator retracted position with the right latch and the left latch in the latch unlocked position and the actuator extended position with the right latch and the left latch in the latch locked position. 
     
     
         18 . The machine of  claim 14 , wherein the variable length actuator is an extendable shaft assembly comprising:
 a motor wherein the left actuator end is a left motor end operatively connected to the left latch; and   a shaft extending from a right motor end of the motor and wherein the right actuator end is a right shaft end operatively connected to the right latch,   wherein the motor is actuatable to retract the shaft to move the extendable shaft assembly to the actuator retracted position and to extend the shaft to move the extendable shaft assembly to the actuator extended position.   
     
     
         19 . The machine of  claim 14 , comprising:
 a right linkage assembly operatively connecting the right actuator end to the right latch, the right linkage assembly comprising:
 a right lever pivotally mounted to the coupler frame proximate the right frame end, 
 a right actuator link pivotally connected between the right actuator end and the right lever, and 
 a right latch link pivotally connected between the right latch and the right lever; and 
   a left linkage assembly operatively connecting the left actuator end to the left latch, the left linkage assembly comprising:
 a left lever pivotally mounted to the coupler frame proximate the left frame end, 
 a left actuator link pivotally connected between the left actuator end and the left lever, and 
   a left latch link pivotally connected between the left latch and the left lever.   
     
     
         20 . The machine of  claim 19 , wherein the right linkage assembly comprises a right spring disposed between the right latch and the right lever and biasing the right latch away from the right lever, and wherein the left linkage assembly comprises a left spring disposed between the left latch and the left lever and biasing the left latch away from the left lever.