Patent Application
20160251820
The present disclosure relates generally to a work tool assembly. More particularly, the present disclosure relates to a coupler of the work tool assembly.
Earth moving equipment, such as excavator, backhoes, or loaders typically includes a moveable arm that connects with a work tool. The work tool may be integrally connected with the arm or may be detachably connected with the arm. In the detachable connection, a coupler acts as an interface between the work tool and the arm. The coupler detachably connects the work tools, such as buckets, breaker, crusher, vibration hammer, etc. to the arm. Couplers may also allow a user to quickly change from one work tool to another. Such couplers may be referred to as quick couplers.
The couplers may require a cylinder force from the arm to couple and lock with the work tool. Moreover, the couplers may increase tip radius between the arm and the work tool, thereby reducing leverage applied to the work tool by the arm and thus, affect a performance of the work tool.
U.S. Pat. No. 6,513,268 relates to a device for coupling an implement to an operating arm of an excavator. The arm includes an additional link for guiding the coupling mechanism. The coupling member pivotally connects the arm and link of the excavator. The coupling device includes a piston member, which is resiliently biased by a spring, and facilitates the slidable communication between the coupling member and the work tool. A joining plate connects the sliding ends of the piston members located in the arm and the link. The joining plate includes a groove, wherein the groove is locked with a position guide during the coupling action. As the position guide is separately connected with the link and the arm, the surface contact of the coupler with the work tool may be less and the performance of the coupling mechanism may be affected. Hence, there is a need of an improved coupling mechanism.
In an aspect of the present disclosure, a coupler for detachably coupling to a work tool is provided. The coupler includes a first coupling member, a second coupling member and a plate member. The first coupling member includes a first pair of actuators. The second coupling member connected with a link of the arm and includes a second pair of actuators. The plate member adapted to couple with each of the first coupling member and the second coupling member. The plate member includes a connecting member to engage with the work tool.
In another aspect a method of coupling a coupler with a work tool of a machine is provided. The coupler having a first coupling member, a second coupling member, a first side plate member, a second side plate member, and a connecting member provided on a surface of the first side plate member and the second side plate member. The method includes retracting a machine actuator to place the coupler in an upright position. The method further includes engaging the first coupling member by a pair of hooks provided on a connecting portion of the work tool, wherein the first coupling member includes a first pair of actuators in a first position. The method further includes extending the machine actuator to place the second coupling member of the coupler on a pair of detents provided on the connecting portion of the work tool, wherein the second coupling member includes a second pair of actuators in the first position. The method further includes moving the first pair and the second pair of actuators from the first position to a second position such that first side plate member and the second side plate member moves laterally towards each other and the connecting member provided on the first side plate member and the second side plate member engage with the work tool to lock the coupler with the work tool.
Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or the like parts. Referring to
The first link 104 is pivotally connected to the arm 102 via a first pin joint 112. Further, a second pin joint 114 pivotally connects the first link 104 to the second link 106. A first coupling member 116 pivotally connects the arm 102 to the coupler 108, while a second coupling member 118 pivotally connects the second link 106 to the coupler 108. In an embodiment, the first coupling member 116 and the second coupling member 118 are components of the coupler 108. A machine actuator 119, such as a hydraulic cylinder, may be provided between the arm 102 and the second link 106 to provide additional actuation of the work tool 110 via the coupler 108, such as rotation of the coupler 108 and the work tool 110 relative to the arm 102 about the second coupling member 118. In the illustrated embodiment, the work tool 110 is an excavating bucket having multiple excavating teeth 120 at a lower end 122. However, in alternative embodiments, the work tool 110 may be a ripper, a drill, and the like.
Referring to
In an embodiment, the second link 106 includes a lifting eye 127 located in a central-mid surface of the second link 106. However, the lifting eye 127 may be positioned anywhere on the second link 106, such as a central-top surface, a central-bottom surface, and the like. The lifting eye 127 may also be used to lift material while the coupler 108 is connected or disconnected from the work tool 110.
In an embodiment, the first and the second coupling members 116, 118 includes a first pair of actuators and a second pair of actuators respectively. As illustrated in the
The second coupling member 118 (as shown in
In an embodiment, the first pair of actuators and the second pair of actuators as pistons 128, 130, 136 and 138 may be extended by an application of hydraulic force and retracted by the action of resilient force. In various other embodiments of the present disclosure, the first pair of actuators and the second pair of actuators may include manual or electric screw actuator. In case of electric screw actuator, the actuators may be extended and retracted by an electric power provided either through an engine of the machine or through any alternate power source, such as, battery provided on the machine.
With combined reference to
Similarly, the second side plate member 142 is fixedly attached to the second piston 130 of the first coupling member 116 and the second piston 138 of the second coupling member 118.
As described above, the first side plate member 140 and the second side plate member 142 connects the first and second pistons 128, 130 of the first coupling member 116 with the first and second pistons 136, 138 of the second coupling member 118. Thus, any movement of the first and second pistons 128, 130 of the first coupling member 116 may actuate a movement of the first and second pistons 136, 138 of the second coupling member 118 and vice versa. In an embodiment, the first and second pistons 128, 130 of the first coupling member 116 may be actuated to move to an extended position by application of hydraulic force and the first and second pistons 136, 138 of the second coupling member 118 moves in tandem to the extended position based on a movement of the first and second pistons 128, 130 of the first coupling member 116. Similarly, on disconnecting the application of the hydraulic force from the first coupling member 116, the first and second pistons 128, 130 of the first coupling member 116 moves to a retracted position and the first and second pistons 136, 138 of the second coupling member 118 moves in tandem with the movement of the first and second pistons 128, 130 of the first coupling member 116. In another embodiment, the first and second pistons 136, 138 of the second coupling member 118 may be actuated to move to an extended position by application of hydraulic force and the first and second pistons 128, 130 of the first coupling member 116 moves in tandem to the extended position based on a movement of the first and second pistons 136, 138 of the second coupling member 118. Similarly, on disconnecting the application of the hydraulic force from the second coupling member 118, the first and second pistons 136, 138 of the second coupling member 118 moves to a retracted position and the first and second pistons 128, 130 of the first coupling member 116 moves in tandem with the movement of the first and second pistons 136, 138 of the second coupling member 118. In another embodiment, the first and second pistons 128, 130 of the first coupling member 116 and the first and second pistons 136, 138 of the second coupling member 118 are actuated to move to an extended position by application of hydraulic force in each of the first coupling member 116 and the second coupling member 118.
In another embodiment, the first coupling member 116 and the second coupling member 118 are dual acting piston cylinders. In such a case, the first piston 128 and the second piston 130 of the first coupling member 116 and the first piston 136 and the second piston 138 of the second coupling member 118 may not be resiliently biased by the first spring 132 and the second spring 134 (shown for first coupling member 116 in
Referring to
As shown in
In other embodiments, the connecting member 150 may include the guide member on the first side plate member 140 extending outwardly and towards the second side plate member 142, and similarly the second side plate member 142 also includes the guide member extending outwardly and towards the first side plate member 140. In such a case, the first plate 154 and the second plate 156 of the work tool 110 may include corresponding slots for the guide members of the first side plate member 140 and the second side plate 142.
In various other embodiments, another coupler such as coupler 162, as illustrated in
Further, the coupler 162 also includes a hydraulic actuator 176 connected in between the first and second side plate members 168, 170. The hydraulic actuator 176 provides the necessary hydraulic force to overcome the resistance provided by the resilient member 172 and moves the first and second side plate members 168, 170 to an extended position. The first and second side plate members 168, 170 also includes a slot 178 proximal to the connection point of the second pin 166 with the first and second side plate members 168, 170. The slot 178 engages a wedge member (similar to guide member 160 of coupler 108) provided on the work tool 110 to lock the work tool 110 with the coupler 162 while the first and second side plate members 168, 170 are in a retracted position.
The present disclosure is applicable to machines, such as excavators, that are used for multiple functions. For example, an excavator may be used for excavating dirt, rock and other material, and during the excavation operations different implements may be required, such as a different size of bucket, an impact breaker or a grapple. The implement assembly 100 can be used to quickly change from one implement to another with ease, thus reducing a time period for which the machine may be unavailable for its intended purpose.
An exemplary connection process of the work tool 110 with the coupler 108 will now be described with reference to
Subsequently, as shown in
Subsequently, as shown in
Subsequently, as shown in
Accordingly, the connecting member 150 which is shown as slot 150 in
In various other embodiments, the implement assembly 100 may also include additional locking means (not shown) to provide a robust engagement of the coupler 108 with the work tool 110.
Further, the coupler 108 is locked with the work tool 110 for performing lifting operation in zero offset condition. Also, the engagement of the present coupler 108 with the work tool 110 provides more surface contact and thus, provides a robust engagement between the coupler 108 and the work tool 110.
In an embodiment, instead of the coupler 108, the lifting eye 127 of the second link 106 may be used for performing the lifting operation. A lifting rope (not shown) may be coupled with the lifting eye 127 for performing the lifting operation. As compared to the couplers provided in prior art, the geometry of the coupler 108 allows using the lifting eye 127 on the second link 106 to lift loads.
For the purpose of disconnecting the coupler 108 from the work tool 110, the hydraulic actuator may supply hydraulic fluid to outwardly extend the pistons 128, 130, 136 & 138 in the first and second coupling members 116, 118 respectively. Consequently, the slots 150 and the guide members 160 slide out of engagement as the first and second side plate members 140, 142 move laterally outwardly relative to each other. Thus, the coupler 108 provides for easy connection and disconnection of the work tool. The ease in connection and disconnection provides for a reduction in downtime of the machine.
In another embodiment, the first coupling member 116 and the second coupling member 118 are dual acting piston cylinders and the pistons 128, 130, 136 and 138 may not be resiliently biased by the first spring 132 and the second spring 134 (shown for first coupling member in
In various other embodiments of the present disclosure, instead of the pistons 128, 130, 136 and 138, the first coupling member 116 and the second coupling member 118 includes a first pair of electric screw actuators and a second pair of electric screw actuators respectively. In such case, an electric power is provided for moving the first pair of actuators and the second pair of actuators from the first position to the second position for locking the coupler 108 with the work tool 110.
In various other embodiments, and as explained in
Subsequently, the hydraulic actuator 176 withdraws the hydraulic force and as a result, the first side plate member 168 and a second side plate member 170 moves laterally towards each other due to the action of the resilient member 172 provided at each connection end of the first and second pins 164, 166 and the first and second side plate members 168, 170. As the first and second side plate members 168, 170 moves to a second position i.e. the retracted position, the slot 178 provided on each of the first and second side plate members 168, 170 engages with the wedge member (similar to guide member 160 of coupler 108) provided on the work tool 110 to lock the coupler 162 with the work tool 110.
While aspects of the present disclosure have been particularly shown and described with reference to the embodiments above, it will be understood by those skilled in the art that various additional embodiments may be contemplated by the modification of the disclosed systems and methods without departing from the spirit and scope of what is disclosed. Such embodiments should be understood to fall within the scope of the present disclosure as determined based upon the claims and any equivalents thereof.
