Fluid-operated gripping apparatus and method for holding a workpiece in a working orientation

Patent metadata

Field	Value
Publication number	US-12246928-B2
Application number	US-201917417260-A
Country	US
Kind code	B2
Filing date	Dec 5, 2019
Priority date	Jan 4, 2019
Publication date	Mar 11, 2025
Grant date	Mar 11, 2025

Abstract

A fluid-operated gripping apparatus for holding a workpiece having a curved sidewall in a working orientation, and associated methods for gripping and holding a workpiece, are provided. Three fluid-operated actuators, each including an actuator rod and a moveable piston arranged within a cylinder, are equally spaced around a perimeter of a workpiece and receive fluid from a single pressurized fluid source. A fluid (e.g., hydraulic or pneumatic) circuit causes the actuators to extend during a closing stroke of the gripping apparatus according to the force equalization principle. Each actuator includes an end effector pivotally coupled with an actuator rod and configured to contact a surface of the workpiece at exactly two points. A backstop configured to contact an end face of the workpiece is coupled with a rotational joint.

First claim

What is claimed is:

1. A gripping apparatus for holding a workpiece in a working orientation, the gripping apparatus comprising:
fluid-operated first, second, and third actuators that are equally spaced about a perimeter of the workpiece and supported on a structural mounting ring, wherein each actuator comprises an actuator rod coupled with a moveable piston arranged to move within a cylinder having an extend chamber and a retract chamber, and wherein the fluid-operated first, second, and third actuators are configured to be coupled to a single pressurized fluid source;
a fluid circuit, comprising the first, second, and third actuators coupled in parallel to the pressurized fluid source, and configured to: (i) supply a pressurized fluid to the extend chamber of each actuator during a closing stroke of the gripping apparatus, (ii) inhibit backflow of the pressurized fluid from the extend chamber of each actuator toward the pressurized fluid source, (iii) maintain a same fluid pressure within the extend chamber of each actuator while the workpiece is held by the gripping apparatus, (iv) release the pressurized fluid from the extend chamber of each actuator during an opening stroke of the gripping apparatus, and (v) supply the pressurized fluid to the retract chamber of each actuator during the opening stroke of the gripping apparatus;
first, second, and third end effectors pivotally coupled with the actuator rods of the first, second, and third actuators, respectively, wherein each end effector is configured to contact a surface of the workpiece at exactly two points; and
a backstop configured to contact a first end face of the workpiece, wherein the backstop is coupled to a three-degree-of-freedom rotational backstop joint.

2. The gripping apparatus of claim 1 , wherein the three-degree-of-freedom rotational backstop joint comprises a ball joint.

3. The gripping apparatus of claim 1 , wherein each end effector comprises a forked end portion that defines a first curved convex surface configured to contact the surface of the workpiece at a first point of the exactly two points, and wherein the forked end portion further defines a second curved convex surface configured to contact the surface of the workpiece at a second point of the exactly two points.

4. The gripping apparatus of claim 3 , wherein an axis of curvature of the first curved surface is arranged 120 degrees apart from an axis of curvature of the second curved surface.

5. The gripping apparatus of claim 1 , wherein each end effector comprises a three-degree-of-freedom rotational joint.

6. The gripping apparatus of claim 1 , wherein the fluid circuit comprises:
a first check valve configured to inhibit backflow of the pressurized fluid from the extend chamber of the first actuator toward the pressurized fluid source;
a second check valve configured to inhibit backflow of the pressurized fluid from the extend chamber of the second actuator toward the pressurized fluid source; and
a third check valve configured to inhibit backflow of the pressurized fluid from the extend chamber of the third actuator toward the pressurized fluid source.

7. The gripping apparatus of claim 6 , wherein the fluid circuit further comprises:
a first actuator-specific valve arranged to permit the pressurized fluid to bypass the first check valve and permit flow from the retract chamber of the first actuator toward a pressurized fluid return or toward a fluid vent during the opening stroke of the gripping apparatus;
a second actuator-specific valve arranged to permit the pressurized fluid to bypass the second check valve and flow from the retract chamber of the second actuator toward the pressurized fluid return or toward the fluid vent during the opening stroke of the gripping apparatus; and
a third actuator-specific valve arranged to permit the pressurized fluid to bypass the third check valve and flow from the retract chamber of the third actuator toward the pressurized fluid return or toward the fluid vent during the opening stroke of the gripping apparatus.

8. The gripping apparatus of claim 7 , wherein:
the first actuator-specific valve comprises a three port, two position, three-way valve arranged to selectively couple the extend chamber of the first actuator to either (i) the first check valve or (ii) the pressurized fluid return or the fluid vent;
the second actuator-specific valve comprises a three port, two position, three-way valve arranged to selectively couple the extend chamber of the second actuator to either (i) the second check valve or (ii) the pressurized fluid return or the fluid vent; and
the third actuator-specific valve comprises a three port, two position, three-way valve arranged to selectively couple the extend chamber of the third actuator to either (i) the third check valve or (ii) the pressurized fluid return or the fluid vent.

9. The gripping apparatus of claim 1 , wherein at least a portion of the backstop is centrally arranged within or proximate to an opening of the structural mounting ring.

10. The gripping apparatus of claim 1 , wherein the actuator rod of each actuator is configured to travel in a substantially horizontal plane.

11. The gripping apparatus of claim 1 , further comprising an adjustable pressure regulator configured to maintain a selected pressure supplied by the pressurized fluid source to the fluid circuit, whereby adjustment of the selected pressure supplied by the pressurized fluid source is configured to adjust a gripping force exerted by the first, second, and third end effectors on the workpiece.

12. The gripping apparatus of claim 1 , wherein the pressurized fluid comprises a liquid.

13. The gripping apparatus of claim 1 , wherein the pressurized fluid comprises a gas.

14. The gripping apparatus of claim 1 , wherein the fluid circuit comprises a five port, two position, four-way valve arranged between the pressurized fluid source and the first, second, and third actuators.

15. The gripping apparatus of claim 1 , wherein the workpiece comprises a substantially cylindrical shape.

16. A method for gripping and holding a workpiece in a working orientation utilizing a gripping apparatus comprising fluid-operated first, second, and third actuators that are equally spaced about a perimeter of the workpiece and supported on a structural mounting ring, first, second, and third end effectors coupled with actuator rods of the first, second, and third actuators, respectively, and a backstop configured to contact a first end face of the workpiece, wherein the backstop is coupled to a three-degree-of-freedom rotational backstop joint and each actuator comprises (i) a cylinder having an extend chamber and a retract chamber and (ii) a moveable piston arranged to move within the cylinder, each moveable piston coupled with a corresponding actuator rod of the first, second, and third actuators, the method comprising:
supplying a pressurized fluid from a single pressurized fluid source to the extend chamber of each of the first, second, and third actuators during a closing stroke of the gripping apparatus, the first, second, and third actuators being coupled in parallel to the pressurized fluid source, while inhibiting backflow of the pressurized fluid from each extend chamber toward the pressurized fluid source, to cause (i) the first end effector to contact a surface of the workpiece only at a first pair of points, (ii) the second end effector to contact the surface of the workpiece only at a second pair of points, and (iii) the third end effector to contact the surface of the workpiece only at a third pair of points;
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Assignees

• Corning Inc

Inventors

• Aguilar Alejandro

Classifications

• H10P72/7608

  characterised by a plurality of separate clamping members, e.g. clamping fingers · CPC title

• B23B31/101

  Chucks with separately-acting jaws movable radially (B23B31/1602, B23B31/16062, B23B31/161, B23B31/16137, B23B31/16175, B23B31/16212, B23B31/1625 and B23B31/16283 take precedence; Chucks with simultaneously acting jaws moving radially B23B31/16) · CPC title

• B25B5/163

  Jaws or jaw attachments · CPC title

• B25B1/22

  Arrangements for turning or tilting vices · CPC title

• B65G47/90 Primary

  Devices for picking-up and depositing articles or materials · CPC title