Releasable fastening system based on ionic polymer metal composites and method of use

• US 20040074070A1
• Filed: 02/07/2003
• Published: 04/22/2004
• Est. Priority Date: 10/19/2002
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations Incorporated (Motors Liquidation Co. GUC Trust)
• Inventors: Barvosa-Carter, William, Momoda, Leslie A., Johnson, Nancy L., Stanford, Thomas B., Browne, Alan Lampe
• Granted Patent: US 6,973,701 B2
• Time in Patent Office: Days
• US Class Current: 24/442
• CPC Class Codes: B64C 33/02 Wings; Actuating mechanisms therefor
• CPC Class Codes: C08L 2201/12 Shape memory
• CPC Class Codes: F16B 2200/77 Use of a shape-memory material
• CPC Class Codes: F16B 2200/81 Use of a material of the hooks-and-loops type
• CPC Class Codes: F16B 2200/83 Use of a magnetic material
• CPC Class Codes: F16B 5/07 by means of multiple interengaging protrusions on the surfaces, e.g. hooks, coils,
• CPC Class Codes: F16F 2224/045 magnetorheological
• CPC Class Codes: Y10T 24/27 including readily dissociable fastener having numerous, protruding, unitary filaments randomly interlocking with, and simultaneously moving towards, mating structure [e.g., hook-loop type fastener]
• CPC Class Codes: Y10T 24/45466 having electric or fluid powered, actuation or release, of interlock
• CPC Class Codes: Y10T 428/24017 Hook or barb

Abstract

A releasable fastening system comprises a knob portion comprising a knob element, a cavity portion comprising a cavity configured to receive the knob element, and an ionic polymer metal composite actuator disposed at the knob element. The ionic polymer metal composite actuator is operable to mechanically interlock the knob element with the cavity. A method of operating a releasable fastening system comprises contacting a knob portion with a cavity portion to form a releasable engagement, wherein the knob portion comprises a knob element disposed on a first support, and wherein the cavity portion comprises a cavity disposed at a second support; maintaining constant shear forces and constant pull-off forces between the knob portion and the cavity portion; and activating an ionic polymer metal composite actuator at the knob portion to facilitate the interlocking of the knob portion and the cavity portion.

Claims

1. A releasable fastening system, comprising:

a knob portion comprising a knob element;

a cavity portion comprising a cavity configured to receive said knob element; and

an ionic polymer metal composite actuator disposed at said knob element, said ionic polymer metal composite actuator being operable to mechanically interlock said knob element with said cavity.

2. The releasable fastening system of claim 1, further comprising a power source disposed in electrical communication with said ionic polymer metal composite actuator.

3. The releasable fastening system of claim 1, wherein said ionic polymer metal composite actuator comprises an electrolytically-actuatable solid polymer electrolyte material.

4. The releasable fastening system of claim 3, wherein said solid polymer electrolyte material is an ion-exchange resin.

5. The releasable fastening system of claim 1, wherein said cavity comprises a lip surface at which said ionic polymer metal composite actuator is engagable.

6. A releasable fastening system, comprising:

a knob portion comprising a knob element and a first support member at which said knob element is supported or attached;

a cavity portion comprising a cavity configured to receive said knob element and a second support member at which said cavity is disposed; and

an ionic polymer metal composite actuator disposed at said knob element, said ionic polymer metal composite actuator comprising a solid polymer electrolyte material, a first electrode disposed at a first surface of said solid polymer electrolyte material, and a second electrode disposed at a second surface of said solid polymer electrolyte material, said ionic polymer metal composite actuator being electrically operable to engage a surface of said cavity to retain said knob element at said cavity.

7. The releasable fastening system of claim 6, wherein said knob element comprises a post configured to be received in said cavity, said post being supported at or attached to said first support member at one end of said post.

8. The releasable fastening system of claim 6, wherein said first electrode is laterally supported at one end of said knob element, said solid polymer electrolyte material is disposed at said first electrode, and said second electrode is supported at an opposing side of said solid polymer electrolyte material.

9. The releasable fastening system of claim 6, wherein said cavity comprises a chamfered surface at an exterior portion thereof.

10. The releasable fastening system of claim 6, wherein said cavity comprises an interior portion defined by an abrupt change in cross-sectional area from an intermediate portion, said interior portion comprising recessed sides that define a lip surface at which said ionic polymer metal composite actuator is engagable.

11. The releasable fastening system of claim 6, wherein said solid polymer electrolyte material comprises a fluorocarbon-type ion exchange resin having sulfonic acid group functionality.

12. A releasable fastening system, comprising:

a knob portion comprising an ionic polymer metal composite actuator, said ionic polymer metal composite actuator comprising a solid polymer electrolyte material, a first electrode disposed at said solid polymer electrolyte material, and a second electrode disposed at said solid polymer electrolyte material; and

a cavity portion comprising a cavity configured to receive said ionic polymer metal composite actuator of said knob portion.

13. The releasable fastening system of claim 12, wherein said cavity comprises a chamfered surface at an exterior portion thereof through which said knob portion is received and a lip portion at an interior portion thereof at which said knob portion is engagable.

14. The releasable fastening system of claim 12, wherein said solid polymer electrolyte material comprises a fluorocarbon-type ion exchange resin having sulfonic acid group functionality.

15. The releasable fastening system of claim 12, wherein said electrodes are fabricated from a material selected from the group consisting of platinum, palladium, rhodium, iridium, ruthenium, osmium, carbon, gold, tantalum, tin, indium, nickel, tungsten, manganese, and combinations of the foregoing materials.

16. A method of operating a releasable fastening system, comprising:

contacting a knob portion with a cavity portion to form a releasable engagement, wherein said knob portion comprises a knob element disposed on a first support, and wherein said cavity portion comprises a cavity disposed at a second support;

maintaining constant shear forces and constant pull-off forces between said knob portion and said cavity portion; and

activating an ionic polymer metal composite actuator at said knob portion to facilitate the interlocking of said knob portion and said cavity portion.

17. The method of claim 16, wherein said activating said ionic polymer metal composite actuator comprises deforming an assembly comprising an ionic polymer metal composite element and an electrode.

18. The method of claim 16, wherein said activating of said ionic polymer metal composite actuator comprises applying a voltage to a solid polymer electrolyte material in a manner to cause the engagement of said ionic polymer metal composite actuator with a surface of said cavity.

19. The method of claim 16, wherein said activating of said ionic polymer metal composite actuator comprises applying a voltage to a solid polymer electrolyte material in a manner to cause the disengagement of said ionic polymer metal composite actuator from a surface of said cavity.