Patent Application
20200190765
The present disclosure relates to a tool coupling arrangement and, more particularly, to a tool coupling arrangement having zero offset.
A tool coupler can be used to increase the functionality and versatility of a host machine by allowing different tools, such as buckets, to be quickly and interchangeably connected to the linkage of the machine (e.g., a stick of an excavator). A pin grabber coupler is a common type of tool coupler. A conventional pin grabber coupler generally includes a frame having a first end that connects to the linkage of the machine and a second end that includes hooks that engage corresponding pins of a tool to thereby connect the tool to the linkage.
The use of a conventional pin grabber coupler introduces an added distance (i.e., an offset) between the end of the linkage and the pins on the tool. This offset may add additional tip radius to the machine, which may reduce the overall breakout forces seen at the end of the tool. In addition, the use of a tool coupler also adds additional weight and cost to the tool coupling arrangement.
U.S. Pat. Publication No. 2017/0321389 to Kovar et al. (the '389 publication) describes a tool coupler assembly that includes a power linkage assembly having a first power link. The first power link may include a first end configured for pivotal connection to a tool, and a second, opposite end configured for pivotal connection to one end of a tool control actuator. The tool control actuator may be connected at an opposite end to a first end of a machine link of a machine, wherein operation of the tool control actuator pivots the tool about a tool pivot axis coaxial with a tool engagement interface at a second end of the machine link. A power linkage actuator may be pivotally connected at a first end for coaxial rotation with the tool engagement interface at the second end of the machine link, and at a second end for coaxial rotation with the first end of the first power link.
One aspect of the present disclosure is directed to a tool coupler for coupling a tool to an end of a machine link. The tool coupler may include a coupler frame, a hook configured to receive a first pin of the tool and configured to attach to the end of the machine link such that the tool coupler is pivotal about an axis, a wedge slidingly received within the coupler frame, and an actuator connected to the wedge to move the wedge away from the hook to bias a second pin of the tool against the coupler frame. The tool coupler mounts the tool to the machine link such that the tool pivots about the axis.
Another aspect of the present disclosure is directed to a tool coupler assembly. The tool coupler assembly may include a tool coupler and a machine link having a distal end configured to receive the first pin of the tool. The tool coupler may include a hook configured to secure the first pin of the tool to the distal end of the machine link, the hook further configured to pivotally attach to the distal end of the machine link, a wedge slidingly received within the coupler frame, and an actuator connected to the wedge to move the wedge away from the first end of the machine link to bias the second pin of the tool against the coupler frame. The tool coupler and the tool are pivotal relative to the machine link about the same axis.
Yet another aspect of the present disclosure is directed to a method of coupling, with zero offset, a tool to a machine. The method may include pivotally attaching the tool coupler to a distal end of a machine link, securing a first pin of the tool to the distal end of the machine, and wedging a second pin of the tool against a frame of the tool coupler. Both the tool coupler and the tool may be pivotal relative to the machine link about the same axis.
Other features and aspects of this disclosure will be apparent from the following description and the accompanying drawings.
Further features and advantages of the invention will become apparent from the description of embodiments using the accompanying drawings. In the drawings:
Referring to the drawings,
The power source 12 may embody an engine such as, for example, a diesel engine, a gasoline engine, a gaseous fuel-powered engine or any other type of combustion engine known in the art. It is contemplated that the power source 12 may alternatively embody a non-combustion source of power such as a fuel cell, a power storage device, or another source known in the art. The power source 12 may produce a mechanical or electrical power output that may then be converted to hydraulic pneumatic power for moving the linkage arrangement 14.
The linkage arrangement 14 may be acted on by actuators to move a tool 18. Any suitable actuators may be used, such as for example, hydraulic actuators, pneumatic actuators, electric actuators, electro-hydraulic actuators, electro-mechanical actuators, or other type of suitable actuator. The linkage arrangement 14 may be configured in a variety of ways. Any configuration of one or more movable links, arms, or the like, that the tool 18 can be mounted to for movement thereof may be used. The linkage arrangement 14 may be complex, for example, including three or more degrees of freedom. In the illustrated exemplary embodiment, the linkage arrangement 14 includes a first machine link 20, such as for example a boom of an excavator, having a first end 22 and a second end 24 opposite the first end 22. The first end 22 of the first machine link 20 is mounted to a frame 26 of the machine 10 to pivot about a horizontal axis 28 (as viewed in
The linkage arrangement 14 may further include a single, double-acting, hydraulic cylinder 42 that is connected to a tool coupling assembly 44. Each of the hydraulic cylinders 30, 40, 42 may include a tube portion and a piston assembly arranged within the tube portion to form a head-end pressure chamber and a rod-end pressure chamber. The pressure chambers may be selectively supplied with pressurized fluid and drained of the pressurized fluid to cause the piston assembly to displace within the tube portion, thereby changing the effective length of hydraulic cylinders 30, 40, 42.
The tool coupling assembly 44 is provided to facilitate a quick connection between the linkage arrangement 14 and the tool 18. The tool coupling assembly 44 may include a tool coupler 46 and a portion of the linkage arrangement 14, such as for example, the second end 36 of the second machine link 32. In the exemplary embodiment of
Referring to
The linkage arrangement 14 may further include a pair of second power links 62. Each of the second power links 62 include a first end 64 and a second end 66. The first end 64 the second power links 62 are pivotally attached to opposite sides of the second machine link 32. The second end 66 of each of the second power links 62 is pivotally attached to the first end 54 of the first power link 50. It should be noted that other configurations of the linkage arrangement 14 may also be possible.
The tool 18 may be configured in a variety of ways. Numerous different tools 18 may be attachable to a single machine 10 and controllable via the operator station 16. Each tool 18 may include a device used to perform a particular task such as, for example, a bucket, a fork arrangement, a blade, a grapple, or any other task-performing device. Although connected in the embodiment of
Referring to
In the illustrated embodiment, the second end 36 is bifurcated having a first leg 82 and a second leg 84 spaced apart from and extending parallel to the first leg 82. In the illustrated embodiment, the second leg 84 is identical to, but a mirror image of, the first leg 82, thus the description of the first leg 82 applies equally to the second leg 84. In other embodiments, however, the second leg 84 may be configured differently than the first leg 82.
The first leg 82 includes a first inner side surface 86 and a first outer side surface 88 generally parallel to and opposite the first inner side surface 86. The space between the first leg 82 and the second leg 84 forms a channel 90 configured to receive a portion of the tool coupler 46. The tool coupling interface 80 includes a first hook 92 defining a downward facing, U-shaped, first recess 94 configured to receive the first tool pin 70. The second leg 84 forms a second hook 96 defining a downward facing, U-shaped, second recess 98 also configured to receive the first tool pin 70. The first and second recesses 94, 98 are configured for coaxial engagement with the first tool pin 70. The first hook 92 and the second hook 96 may be fixedly connected to the second machine link 32. For the purposes of this disclosure the phrase fixedly connected may include bolted to, welded to, integrally formed with or otherwise rigidly adjoined to.
The first inner side surface 86 includes a generally C-shaped or arcuate first groove 100 extending around the first recess 94. The first groove 100 is open ended such that both ends of the first groove 100 open into the first recess 94. A second groove 101 (
The tool coupler 46 is configured to engage the tool pins 70, 72 to attach the tool 18 to the second machine link 32. The tool coupler 46 may be configured in a variety of ways. Referring to
In the illustrated embodiment, the forward portion 122 defines a power link interface 136. The power link interface 136 may be configured in a variety of ways. Any interface that allows the tool coupler 46 to be pivotally mounted to the first power link 50 may be used. In the illustrated embodiment, the power link interface 136 includes a channel 138 extending through the frame 120 from the top surface 132 to the bottom surface 130 and a cross pin 140 that extends across the channel 138. The second end 56 of the first power link 50 is adapted to pivotally mount to the cross pin 140. A bridge portion 142 (
The forward portion 122 of the tool coupler 46 includes a neck portion 145 that attached the forward portion 122 to the rearward portion 124. The rearward portion 124 of the tool coupler 46 includes a front surface 150 extending at an angle α to the bottom surface 130 of the forward portion 122 to form a corner or notch 151 therebetween. The front surface 150 has a first width W1. The rearward portion 124 includes a rear surface 152 opposite the front surface 150 and a bottom surface 154 extending between the front surface 150 and the rear surface 152. The bottom surface 154 may be curved or contoured to be complementary of a profile of the tool 18. For example, in the illustrated embodiment, the bottom surface 154 is curved to be complementary to the top plate 156 (
In the illustrated embodiment, the rearward portion 124 defines a tool support interface 160. The tool support interface 160 may be configured in a variety of ways. Any configuration that allows the tool coupler 46 to be pivotally coupled to the tool coupling interface 80 of the second machine link 32 and facilitates retaining the tool 18 onto the second machine link 32 may be used. In the illustrated embodiment, the tool support interface 160 is positioned on a projection 162 that extends rearward from the rear surface 152. The projection 162 has a second width W2, which is smaller than the first width W1.
The tool support interface 160 includes a hook 164 defining a rearward facing, U-shaped recess 166. The hook 164 may be fixedly connected to the frame 120. For the purposes of this disclosure the phrase fixedly connected may include bolted to, welded to, integrally formed with or otherwise rigidly adjoined to. The recess 166 is configured to receive the first tool pin 70 and retain the first tool pin 70 in the first recess 94 and the second recess 98 on the second machine link 32. The hook 164 includes a first side surface 168 and a second side surface 170 opposite the first side surface 168. The first side surface 168 includes a first C-shaped, or arcuate ridge or tongue 172 configured to be received in the first groove 100 on the first hook 92 of the tool coupling interface 80. The second side surface 170 includes a second C-shaped, or arcuate ridge or tongue 174 configured to be received in the second groove 101 on the second hook 96 of the tool coupling interface 80. Thus, the tool support interface 160 on the tool coupler 46 and the tool coupling interface 80 on the second end 36 of the second machine link 32 form a tongue and groove arrangement. As discussed above, alternatively, the first and second ridge 172, 174 may be formed on the second end 36 of the second machine link 32 and mating grooves may be formed on the tool coupler 46.
In the illustrated embodiment, the first ridge 172 and the second ridge 174 are each formed on bolt-on components that are attached to the first side surface 168 and a second side surface 170, respectively. In other embodiments, however, the first ridge 172 and the second ridge 174 may be formed integrally with the hook 164 or attached to the hook 164 in some other manner.
The projection 162 includes a top surface 176 and a bottom surface 178 opposite the top surface 176. The bottom surface 154 and/or the bottom surface 178 may be curved or contoured to be complementary of a profile of the tool 18. For example, in the illustrated embodiment, the bottom surface 178 is curved to be complementary to the top plate 156 of the illustrated bucket. In the illustrated embodiment, the bottom surface 154 forms a continuous surface with the bottom surface 178. In other embodiments, however, the bottom surface 154 and the bottom surface 178 may not form a continuous surface.
As shown in
In the illustrated embodiment, the tool locking system 180 may include tool pin interface 182 that is slidingly disposed within a channel 184 in the rearward portion 124. The channel 184 is open at the front surface 150. The tool pin interface 182 may be configured in a variety of way. In the illustrated embodiment, the tool pin interface 182 is a wedge having an upward-facing, inclined surface 186.
The tool locking system 180 may also include an actuator 188 configured to move tool pin interface 182 in a direction represented by an arrow 190. The actuator 188 may be configured in a variety of ways. Any type of actuator that can be operated to change in length so as to exert a force at each end and move the tool pin interface 182 to bias the first and/or second tool pins 70, 72 against portions of tool coupler 46 may be used. Suitable actuators may include a hydraulic actuator, a pneumatic actuator, an electric actuator, electro-hydraulic actuator, electro-mechanical actuator, a manual screw actuator, or other type of suitable actuator. In the illustrated embodiment, the actuator 188 is a hydraulic actuator including a rod 192 having a first end 194 pivotally attached to the tool pin interface 182 and a second end 196 opposite the first end 194. A piston 198 is fixably attached on the rod 192 at, or proximate, the second end 196. The rod 192 and piston 198 are slideably disposed within a cylinder 200. In the illustrated embodiment, the cylinder 200 is integrally formed within the frame 120 of the tool coupler 46. For example, the cylinder 200 may be machined into the frame 120 or cast as part of the frame 120. In other embodiments, however, the cylinder 200 may not be integrally formed in the frame 120.
The cylinder 200 has a closed first end 202 and an open second end 204 through which the rod 192 extends. A seal 206 is disposed at the second end 204 to retain working fluid within the cylinder 200. A first fluid port 208 is in fluid communication with the cylinder 200 between the piston 198 and the first end 202 and a second fluid port 210 is in fluid communication with the cylinder 200 between the piston 198 and the second end 204 to route working fluid into and out of the cylinder 200. In the illustrated embodiment, a hydraulic valve assembly 212 and hydraulic lines 214 are mounted to a top surface 176 to selectively provide working fluid to the cylinder 200 via the first and second fluid ports 208, 210.
The tool coupler 46 may also include a locking arrangement 220 for locking the tool pin interface 182 in place. The locking arrangement 220 may be configured in a variety of ways. Any configuration capable of locking the tool pin interface 182 in position, even if a loss of working fluid pressure occurs, may be used. For example, the locking arrangement 220 may be a mechanical lock arrangement that retains the tool pin interface 182 in an extended or locked position even if a loss of working fluid pressure occurs. The locking arrangement 220 may include an actuator to engage the tool pin interface 182 or move another portion of the locking arrangement into engagement with and/or out of engagement with the tool pin interface 182. The actuator may be a hydraulic actuator, a pneumatic actuator, an electric actuator, electro-hydraulic actuator, electro-mechanical actuator, a manual screw actuator, or other type of suitable actuator.
Referring to
The stem portion 230 include an engagement surface 232 configured to engage the tool pin interface 182. In the illustrated embodiment, the engagement surface 232 includes a plurality of teeth, ridges, or other structure for engaging the tool pin interface 182 and preventing the tool pin interface 182 from retracting. The tool pin interface 182 includes a corresponding engagement surface 234 for engaging the engagement surface 232 of the plunger 222. The tool pin interface 182 may include a plurality of teeth, ridges, or other structure for engaging the plunger 222 such that the plunger 222 prevents the tool pin interface 182 from retracting. In the illustrated embodiment, the engagement surface 232 of the plunger 222 and the engagement surface 234 of the tool pin interface 182 form a ratchet allowing the tool pin interface 182 to extend but not retract when the engagement surfaces 232, 234 are engaged.
The locking arrangement 220 may be configured to bias the plunger 222 inward such that the engagement surface 232 of the plunger 222 is biased against the engagement surface 234 of the tool pin interface 182. In the illustrated embodiment, the locking arrangement 220 includes a biasing element 236, such as for example, a spring, a least partially received in a recess 238 formed in the head portion 228 of the plunger 222.
The locking arrangement 220 may also be configured to selectively disengage the engagement surface 232 of the plunger 222 from the engagement surface 234 of the tool pin interface 182. In the illustrated embodiment, the locking arrangement 220 includes a fluid passage 240 in fluid communication with the valve assembly 212. The fluid passage 240 is configured to direct working fluid between the inward facing shoulder 231 of the plunger 222 and the outward facing shoulder 226 of the bore 224 to move the plunger 222 outward against the bias of the biasing element 236. In the illustrated embodiment, the plunger 222 includes an annular recess 242 or chamfer located at the radial edge of the inward facing shoulder 231 to provide an initial area against which the working fluid can act.
The presently disclosed tool coupler 46 may be applicable to a variety of machines, such as excavators, backhoes, loaders, and motor graders, to increase the functionality of these machines. For example, a single excavator may be used for moving 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 disclosed tool coupler 46 can be used to quickly change from one implement to another with ease, thus reducing the time the machine is unavailable for its intended purpose.
To attach the tool 18 to the second machine link 32, the tool coupler 46 is shown attached to the second machine link 32 and is placed in a first position in which the hydraulic cylinder 42 is in a retracted position, as shown in
Once the first tool pin 70 is received in the aligned recesses 94, 98, 166, the hydraulic cylinder 42 is moved to an extended position to pivot the tool coupler 46 (in a clockwise direction relative to the first position as shown in
In addition, in the second position, the second tool pin 72 is positioned at or near the corner 151 between bottom surface 130 and the front surface 150 on the tool coupler 46. As shown in
Unlike a conventional tool pin quick coupler, the tool coupler 46 does not introduce an “offset” at the end of the second machine link 32. As used in this application, “offset” refers to the shortest distance between a line drawn through both tool pins 70, 72 on the tool 18 and the point where the tool coupler 46 pivotally attaches to the second machine link 32. As described and illustrated above, the first tool pin 70 on the tool 18 is received in the recess 166 in the tool coupler 46 and both the first and second recess 94, 98 in the second machine link 32 such that the tool coupler 46 and the tool 18 are pivotal about the same horizontal axis 48. Thus, since the tool coupler 46 and the tool 18 are coaxially pivotally mounted to the second machine link 32, there is zero offset introduced by use of the tool coupler 46. Therefore, overall breakout forces are not reduced due to additional tip radius being added to the machine with the use of a quick coupler.
Further, as the tool pin interface 182 is moved toward the second tool pin 72, the ratcheting action of the locking arrangement 220 (
To disengage the locking arrangement 220, the valve assembly 212 can route working fluid to the actuator 188 via the second fluid port 210 causing the rod 192 and piston 198 to retract the tool pin interface 182 in a direction toward from the second end 36 of the second machine link 32 and the hook 164. Prior to, or concurrently, with routing working fluid to the second fluid port 210, the valve assembly 212 can route working fluid through the fluid passage 240 to move the plunger 222 out of engagement with the tool pin interface 182 to allow the rod 192 and piston 198 to retract the tool pin interface 182.
In addition, the configuration of the first power link 50 prevents undesired contact between the body 52 of the first power link 50 and the hydraulic valve assembly 212 and hydraulic lines 214 mounted to a top surface 176 of the tool coupler 46. In particular, in the second position of the tool coupler 46, the hydraulic valve assembly 212 and hydraulic lines 214 are received in the recess or aperture 60 in the body 52 and do not contact the body 52.
It will be apparent to those skilled in the art that various modifications and variations can be made to the tool coupler assembly of the present disclosure without departing from the scope of the disclosure. Other embodiments will be apparent to those skilled in the art from consideration of the specification and practice of the tool coupler assembly disclosed herein. For example, although the disclosed tool coupler is illustrated attaching to the second machine link via ridge and groove features, other features may be provided that also allow coaxial pivotal engagement between the second machine link and the tool and tool coupler. It is intended that the specification and examples be considered as exemplary only, with a true scope of the disclosure being indicated by the following claims and their equivalent.
It will be appreciated that the foregoing description provides examples of the disclosed system and technique. However, it is contemplated that other implementations of the disclosure may differ in detail from the foregoing examples. All references to the disclosure or examples thereof are intended to reference the particular example being discussed at that point and are not intended to imply any limitation as to the scope of the disclosure more generally. All language of distinction and disparagement with respect to certain features is intended to indicate a lack of preference for those features, but not to exclude such from the scope of the disclosure entirely unless otherwise indicated.
