Movable Gripper Tool

Abstract

To provide a cost-effective gripper tooling device that can accommodate variously configured work-pieces.SOLUTION: A gripping device for gripping a workpiece. The gripping device includes at least one gripping element configured for contacting the workpiece, at least one articulating finger jaw, and a mounting block connecting the shaft of the at least one gripping element to the at least one articulating finger jaw. The mounting block includes an articulation stopper having a first stopping surface and a second stopping surface. The gripping device further includes a stopping member connected to the shaft. The stopping member is configured for contacting one of the first stopping surface and the second stopping surface to limit a rotation of the shaft relative to the mounting block. The stopping member is in the form of one of a pin and a fastener.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] 1. Field of the Invention The present invention relates to mechanical grippers and, more particularly, to jaw tooling for such grippers.

[0002] 2. Description of the Prior Art A gripper is a mechanical device with one or more jaws that are moved toward and away from each other by an electric motor, a fluid-driven piston, or another mechanism. Often, a tool attached to the gripper jaws is responsible for transferring the gripper's force to the workpiece, which can then be held, moved, or rotated. The tool must be capable of gripping workpieces that vary in size, shape, design, material, mass, etc.

[0003] Typically, gripper jaw tools are designed to match the contours of a workpiece so that when the gripper applies force to grip the member, the tool conforms to the workpiece, resulting in maximum force transfer to the part. Designing and manufacturing tooling to fit workpieces of different sizes, shapes, designs, materials, masses, etc. is not only costly but also far less effective at maximizing the gripping force applied to the workpiece.

[0004] U.S. Patent No. 10,011,025, commonly owned by the applicant, discloses a gripper tooling device that allows the tooling to be adapted to workpieces that differ in size, shape, design, material, mass, etc. The gripper tooling device has gripper elements that are partially rotatable relative to the gripper jaws to which the gripper elements are attached. Thus, the gripper elements can accommodate workpieces of different configurations by rotating relative to the gripper jaws.

[0005] What is needed in the art is a cost-effective gripper tooling apparatus that can accommodate a variety of differently configured workpieces.

[0006] Summary of the Invention The present invention provides a gripping device for gripping a workpiece. The gripping device includes at least one gripping element configured to contact a workpiece, at least one movable articulating finger jaw, and an assembly block connecting a shaft of the at least one gripping element to the at least one movable finger jaw. The assembly block includes an articulation stop having a first stop surface and a second stop surface. The gripping device further includes a stop member connected to the shaft. When the shaft rotates to accommodate the at least one gripping element to receive the workpiece, the stop member contacts the first stop surface or the second stop surface, thereby preventing further rotation of the shaft in a clockwise or counterclockwise direction.

[0007] One aspect of the present invention relates to a gripping device for gripping a workpiece. The gripping device includes at least one gripping element configured to contact the workpiece. The at least one gripping element includes a shaft. The gripping device further includes at least one movable finger jaw and an assembly block connecting the shaft to the at least one movable finger jaw. The assembly block includes an articulation stop having a first stop surface and a second stop surface. The gripping device further includes a stop member connected to the shaft. The stop member is configured to contact one of the first stop surface and the second stop surface and limits rotation of the shaft relative to the assembly block. The stop member is in the form of one of a pin and a fastener.

[0008] Another aspect of the present invention relates to a method for gripping a workpiece, the method including providing a gripping device for gripping a workpiece. The gripping device includes at least one gripping element configured to contact the workpiece. The at least one gripping element includes a shaft. The gripping device includes at least one movable finger jaw and an assembly block connecting the shaft to the at least one movable finger jaw. The assembly block includes an articulation stop having a first stop surface and a second stop surface. The gripping device further includes a stop member connected to the shaft. The stop member is in the form of one of a pin and a fastener. The method further includes positioning the gripping device relative to the workpiece. The method further includes actuating the gripping device such that the at least one gripping element contacts the workpiece and the shaft rotates relative to the assembly block until the stop member contacts one of the first stop surface and the second stop surface.

[0009] An advantage of the present invention is that the gripper jaw tooling can automatically adapt to workpieces of different sizes, shapes, designs, materials, masses, etc., thereby eliminating the need for custom gripper jaw tooling to complement various workpieces.

[0010] Another advantage of the present invention is that the movable section of the gripper jaw tooling can be constrained by a predefined, adjustable amount, thereby providing secure attachment of the workpiece.

[0011] Yet another advantage of the present invention is that the gripping elements can be easily connected to and disconnected from the gripper jaws for easy repair, replacement or cleaning of the various components of the gripper tool apparatus.

[0012] The above and other features and advantages of the present invention, as well as the manner in which they are achieved, will become more apparent and the invention will be better understood by referring to the following description of embodiments of the invention in connection with the accompanying drawings. [Brief explanation of the drawings]

[0013] [Figure 1] 1A-1C are isometric and exploded views showing details of one embodiment of a gripper jaw tool according to the present invention; [Figure 2] FIG. 2 is a plan view of the gripper jaw tool shown in FIG. 1. [Figure 3] 2 is an isometric view of an alternative embodiment of the gripper jaw tool shown in FIG. 1. FIG. [Figure 4] 1A-1C are isometric and exploded views showing details of one embodiment of a gripper jaw tool according to the present invention; [Figure 5] FIG. 5 is a plan view of the gripper jaw tool shown in FIG. 4. [Figure 6] 5 is an isometric view of an alternative embodiment of the gripper jaw tool shown in FIG. 4.

[0014] Corresponding reference characters indicate corresponding parts throughout the several views. The examples set forth herein illustrate embodiments of the present invention and should not be construed as limiting the scope of the present invention in any way.

[0015] Detailed Description of the Invention 1 and 2, there is shown one embodiment of a gripping apparatus 210 in accordance with the present invention. The gripping apparatus 210 has a body 212, at least one gripper jaw 214, and a movable gripper tool assembly 220. The gripping apparatus 210 includes at least one additional gripper jaw 214 and a movable gripper tool assembly 220 to provide a means for gripping a workpiece.

[0016] The movable gripper tool assembly 220 includes a mounting block 222, a stop pin 224, a mounting block attachment member 226, and at least one gripping element 228. The gripping element 228 includes a finger 230, a finger extension 232, and a finger shaft 234 with a through hole 236. The mounting block 222 includes the through hole 238, an articulation stop 240, and an attachment member through hole 242. The articulation stop 240 may be in the form of one or more protrusions, such as tabs, extending outward from the body of the mounting block. The one or more protrusions define stop surfaces 246, 250 ( FIG. 2 ). For example, the articulation stop 240 may be in the form of a single C-shaped protrusion extending outward from the body of the mounting block 222.

[0017] The gripping element 228 is rotatably mounted to the assembly block 222 by inserting the finger shaft 234 into the through-hole 238 and securing the retaining clip 252. The stop pin 224 may be rigidly connected to the shaft 234. For example, the stop pin 224 may be press-fit or otherwise rigidly attached through the finger shaft through-hole 236. The shaft through-hole 236 may be centered along the transverse or vertical axis of the shaft 234 such that the stop pin 224 is coaxial with the transverse axis of the shaft 234. The assembly block 222, with or without the gripping element 228 rotatably mounted thereto, is attached to the jaw 214 by the mounting member 226 and the through-hole 242.

[0018] Referring now to FIG. 2 , the operation of the movable gripper tool assembly 220 will be described. A cross-sectional view along line II illustrates both directions of rotation (“articulation”) of the gripping element 228 relative to the assembly block 222. Rotation in both directions is limited as shown in detail view J. The assembly block 222 includes at least two stop surfaces 246 and 250 in the path of the stop pin 224, as shown in detail view J. When attached to the assembly block 222 by a retaining clip 252, the gripping element 228 can rotate counterclockwise until the stop pin 224 contacts the stop surface 246, which prevents further counterclockwise rotation. Similarly, the gripping element 228 can rotate clockwise until the stop pin 224 contacts the stop surface 250, which prevents further clockwise rotation.

[0019] In one embodiment, as shown in detail view J, the articulating angle K of the gripping element 228 relative to the assembly block 222 is limited to 10 degrees in the clockwise direction, and the articulating angle L of the gripping element 228 relative to the assembly block 222 is limited to 6 degrees in the counterclockwise direction.

[0020] The horizontal distance from the longitudinal axis of stop pin 224 to either the outer edge of stop surface 246 or the outer edge of stop surface 250 changes the angle of rotation (movement) in the respective rotational directions. More specifically, increasing the horizontal distance from the longitudinal axis of stop pin 224 to either the outer edge of stop surface 246 or the outer edge of stop surface 250 increases the angle through which gripping element 228 can move. Similarly, decreasing the horizontal distance from the longitudinal axis of stop pin 224 to either the outer edge of stop surface 246 or the outer edge of stop surface 250 decreases the angle through which gripping element 228 can move. The horizontal distance between the longitudinal axis of stop pin 224 and stop surfaces 246, 250 can be adjusted by changing the position of shaft through-hole 236 and / or the position of the protrusion on articulation stop 240.

[0021] Referring to FIG. 3, another embodiment of a gripping apparatus 210' is shown together with a gripper tool assembly 220'. The only difference between the gripping apparatus 210' and 210 is that the gripper tool assembly 220' does not include a mounting member 226 or a separate assembly block 222 with a through-hole 242. The gripping element 228 is rotatably coupled directly to at least one movable finger jaw 214'. The finger jaw 214' includes a body with an integral assembly block including articulation stops in the form of one or more protrusions defining stop surfaces 246, 250. Identical elements are identified with identical reference numerals.

[0022] 4 and 5, there is shown another embodiment of a gripping apparatus 310 in accordance with the present invention. The gripping apparatus 310 includes a body 312, at least one gripper jaw 314, and a movable gripper tool assembly 320. The gripping apparatus 310 includes at least one additional gripper jaw 314 and a movable gripper tool assembly 320 to provide a means for gripping a workpiece.

[0023] Movable gripper tool assembly 320 includes a mounting block 322, a stop fastener, e.g., a screw 324, a mounting block attachment member 326, and at least one gripping element 328. Grip element 328 includes a finger 330, a finger extension 332, and a finger shaft 334 with a threaded hole 336. Mounting block 322 includes an articulation stop 340 in the form of a limiting notch 340, e.g., a slot or hole 340, and an attachment member through hole 342. Mounting block 322 also includes at least two interior surfaces of slot or hole 340 that define at least two stop surfaces 346, 350 (FIG. 5).

[0024] The gripping element 328 is rotatably mounted to the assembly block 322 by inserting the finger shaft 334 into the through hole 338 and securing it with the stop screw 324. The stop screw 324 may be rigidly connected to the shaft 334. For example, the stop screw 324 may be threaded into a threaded hole 336 in the finger shaft. The stop screw 324 may be eccentric with respect to the longitudinal axis of the notch 340. For example, the threaded hole 336 may be eccentric or non-coaxial with respect to the transverse or vertical axis of the shaft 334 such that the stop screw 324 is eccentric with respect to the transverse axis of the shaft 334. Furthermore, the notch 340 may be offset from the centerline of the through hole 338 such that the longitudinal axis of the stop screw 324 is offset, i.e., not equidistant from both interior walls of the notch 340, when inserted into the threaded hole 336. An assembly block 322 , with or without a gripping element 228 rotatably mounted thereon, is attached to the jaws 314 by means of a mounting member 326 and a through hole 342 .

[0025] Referring now to FIG. 5 , operation of the movable gripper tool assembly 320 will be described. A cross-sectional view along line MM illustrates both directions of rotation (“articulation”) of the gripping element 328 relative to the assembly block 322. Rotation in both directions is limited as shown in detail view N. Stop surfaces 346 and 350 reside in the path of the stop screw 324, as shown in detail view N. When attached to the assembly block 322 by the stop screw 324, the gripping element 328 can rotate clockwise until the head of the stop screw 324 contacts stop surface 346, which prevents further clockwise rotation. Similarly, the gripping element 328 can rotate counterclockwise until the head of the stop screw 324 contacts stop surface 350, which prevents further counterclockwise rotation.

[0026] In one embodiment, as shown in detail view N, the angle of movement P of the gripping element 328 relative to the assembly block 322 is limited to 21 degrees in the clockwise direction, and the angle of movement R of the gripping element 328 relative to the assembly block 322 is limited to 13 degrees in the counterclockwise direction.

[0027] The horizontal distance from the longitudinal axis of stop screw 324 to either the outer edge of stop surface 346 or the outer edge of stop surface 350 changes the angle of rotation (movement) in the respective rotational directions. More specifically, increasing the horizontal distance from the longitudinal axis of stop screw 324 to either the outer edge of stop surface 346 or the outer edge of stop surface 350 increases the angle through which gripping element 328 can move. Similarly, decreasing the horizontal distance from the longitudinal axis of stop screw 324 to either the outer edge of stop surface 346 or the outer edge of stop surface 350 decreases the angle through which gripping element 328 can move. The horizontal distance between the longitudinal axis of stop screw 324 and stop surfaces 346, 350 can be adjusted by changing the position of shaft threaded hole 336 and / or the position of notch 340. As shown, the longitudinal axis of the stop screw 324 is horizontally offset from the longitudinal axis of the notch 340 .

[0028] The vertical distance from the center of the finger shaft 334 to the top of the head of the stop screw 324 also changes the angle of rotation (movement) in both directions. More specifically, increasing the vertical distance from the center of the finger shaft 334 to the top of the head of the stop screw 324 decreases the angle through which the gripping element 328 can move. Similarly, decreasing the vertical distance from the center of the finger shaft 334 to the top of the head of the stop screw 324 increases the angle through which the gripping element 328 can move.

[0029] The diameter of the head of the stop screw 324 also changes the angle of rotation (movement) in both directions. More specifically, increasing the diameter of the head of the stop screw 324 decreases the angle through which the gripping element 328 can move. Similarly, decreasing the diameter of the head of the stop screw 324 increases the angle through which the gripping element 328 can move.

[0030] Referring to FIG. 6, another embodiment of a gripping device 310' is shown together with a gripper tool assembly 320'. The only difference between the gripping devices 310' and 310 is that the gripper tool assembly 320' does not include a mounting member 326 or a separate assembly block 322 with a through-hole 342. The gripping element 328 is rotatably coupled directly to at least one movable finger jaw 314'. The finger jaw 314' includes a body with an integral assembly block having limiting notches, e.g., slots or holes, that define at least two stop surfaces (not numbered). Identical elements are identified with identical reference numerals.

[0031] According to another aspect of the present invention, an operator and / or control system may perform a method for gripping a workpiece. The method may include the initial step of providing a gripping device 210′, 210, 310′, 310 as described above. The method may also include the step of positioning the gripping device 210′, 210, 310′, 310 relative to the workpiece. The method may then include the step of actuating the gripping device 210′, 210, 310′, 310, whereby at least one gripping element of the gripping device 210′, 210, 310′, 310 contacts the workpiece, which then rotates the shaft until the stop member contacts one of the stop surfaces. The method may further include the step of adjusting a rotation limit of the shaft by adjusting the position of the stop member relative to the shaft.

[0032] While the present invention has been described with respect to at least one embodiment, the present invention can be further modified within the spirit and scope of this disclosure. Accordingly, this application is intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the scope of the appended claims.

Claims

1. A gripping device that grips a workpiece, at least one gripping element configured to contact the workpiece and including a shaft; at least one movable finger jaw; an assembly block connecting the shaft to the at least one movable finger jaw, the assembly block including an articulation stop having a first stop surface and a second stop surface, the assembly block including a body, the articulation stop of the assembly block being in the form of a notch, the notch including an interior wall, the first stop surface being a first interior wall of the notch and the second stop surface being a second interior wall of the notch parallel to the first interior wall; a stopper member connected to the shaft, the stopper member being configured to contact one of the first stopper surface and the second stopper surface to limit rotation of the shaft relative to the assembly block, the stopper member being in the form of a fastener, the fastener being a screw received by the shaft within the notch; A gripping device having:

2. A gripping device that grips a workpiece, at least one gripping element configured to contact the workpiece and including a shaft; at least one movable finger jaw; an assembly block connecting the shaft to the at least one movable finger jaw, the assembly block including an articulation stop having a first stop surface and a second stop surface, the assembly block including a body, the articulation stop of the assembly block being in the form of at least one protrusion extending outwardly from the body of the assembly block; a stopper member connected to the shaft, the stopper member being configured to contact one of the first stopper surface and the second stopper surface to limit rotation of the shaft relative to the assembly block, the stopper member being in the form of a pin, the stopper member being formed as a single rod-shaped member without multiple bends; A gripping device having:

3. The gripping device of claim 1 , wherein the stop member is rigidly connected to the shaft.

4. the first stop surface defines a first angle of movement of the at least one gripping element that sets a first rotation limit of the shaft in a first rotation direction; 2. The gripping device of claim 1, wherein the second stop surface defines a second angle of movement of the at least one gripping element that sets a second rotational limit for the shaft in a second rotational direction opposite the first rotational direction.

5. 3. The gripping device of claim 2, wherein the first stop surface is oriented at a first angle and the second stop surface is oriented at a second angle different from the first angle.

6. The gripping device of claim 2 , wherein the at least one protrusion is in the form of a single C-shaped protrusion.

7. The gripping device of claim 1 , wherein the stop member is horizontally offset relative to the notch.

8. 2. The gripping device of claim 1, wherein the stop member is in the form of the fastener, the fastener being an adjustable fastener whereby the position of the fastener is adjustable relative to the shaft to adjust the rotational limit of the shaft.

9. The grasping device of claim 8 , wherein the adjustable fastener is in the form of a screw.

10. A method for gripping a workpiece, comprising: providing a gripping device for gripping a workpiece, the gripping device including: at least one gripping element configured to contact the workpiece and including a shaft; at least one movable finger jaw; an assembly block connecting the shaft to the at least one movable finger jaw, the assembly block including an articulation stop having a first stop surface and a second stop surface; and a stop member connected to the shaft, the stop member being in the form of a fastener, the assembly block including a body, the articulation stop of the assembly block being in the form of a notch, the notch including an internal wall, the first stop surface being a first internal wall of the notch, the second stop surface being a second internal wall of the notch parallel to the first internal wall, and the fastener being a screw received by the shaft within the notch; positioning the gripping device relative to the workpiece; actuating the gripping device such that the at least one gripping element contacts the workpiece and the shaft rotates relative to the assembly block until the stop member contacts one of the first stop surface and the second stop surface; The method has the following features.

11. The method of claim 10 further comprising adjusting the rotational limit of the shaft by adjusting the position of the stop member relative to the shaft.

12. The method of claim 10 , wherein the stop member is horizontally offset relative to the notch.

13. 11. The method of claim 10, wherein the stop member is in the form of the fastener, the fastener being an adjustable fastener whereby an adjustable position of the fastener relative to the shaft can adjust the rotational limit of the shaft.

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