Releasable fastener system

• US 20040074063A1
• Filed: 11/26/2002
• 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: Ulicny, John C., Golden, Mark A.
• Granted Patent: US 6,983,517 B2
• Time in Patent Office: Days
• US Class Current: 24/442
• CPC Class Codes: A41D 2300/326 using hooks and eyelets
• CPC Class Codes: A44B 18/0003 Fastener constructions A44B18/0023, A44B18/0046 take precedence
• CPC Class Codes: A44B 18/0007 in which each part has similar elements
• CPC Class Codes: A44B 18/0096 Shape memory materials
• CPC Class Codes: A44D 2203/00 Fastening by use of magnets
• 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 24/32 having magnetic fastener
• CPC Class Codes: Y10T 428/24017 Hook or barb

Abstract

A releasable fastener system comprises two hook portions. The hook portions each include a support and a plurality of closely spaced upstanding hook elements extending from one side thereof. When the two hook portions are pressed together they interlock to form a releasable engagement. The resulting joint created by the engagement is relatively resistant to shear and pull forces and weak in peel strength forces. The head elements of the hook elements are formed of a material that provides a change in directional orientation of the head elements. In this manner, the directional orientation of the head elements of the hook elements can be remotely changed to provide a reduction or magnification in the shear and/or pull-off forces.

Claims

1. A releasable fastener system comprising:

a first portion comprising a first support and a plurality of first hook elements disposed on a surface, wherein the first hook elements comprise head elements at ends of the first hook elements;

a second portion comprising a second support and a plurality of second hook elements disposed on a surface, wherein the second hook elements comprise head elements at ends of the second hook elements, wherein the head elements of the second hook elements comprise a material adapted to change a directional orientation of the head elements of the second hook elements upon receipt of a magnetic signal; and

an activation device coupled to the plurality of the second hook elements, the activation device being operable to selectively provide the magnetic signal to the head elements of the second hook elements, wherein the magnetic signal effectuates a change in the directional orientation of the head elements of the second hook elements to reduce or increase a shear force and/or a pull-off force.

2. The releasable fastener system of claim 1, wherein the magnetic signal comprises a magnetic field oriented in a direction to effectuate a change in the directional orientation of the head elements of the second hook elements by rotating the head elements of the second hook elements substantially in an x-plane.

3. The releasable fastener system of claim 1, wherein the head elements of the first and second hook elements comprise a J-shape, an L-shape, a multi-tined anchor shape, or a T-shape.

4. The releasable fastener system of claim 1, wherein the first hook elements engage with the second hook elements when the first portion is pressed into face-to-face engagement with the second portion.

5. The releasable fastener system of claim 1, wherein the magnetic signal effectuates a change, wherein the head elements of the second hook elements are substantially parallel to the head elements of the first hook elements, to reduce a shear force and/or a pull-off force.

6. The releasable fastener system of claim 1, wherein the magnetic signal effectuates a change, wherein the head elements of the second hook elements are substantially perpendicular to the head elements of the first hook elements forming an interlocking system to increase a shear force and/or a pull-off force.

7. The releasable fastener system of claim 1, wherein the head elements of the second hook elements comprise a magnetic material, a magnetorheological fluid, a magnetorheological elastomer, or combinations comprising at least one of the foregoing materials.

8. The releasable fastener system of claim 1, wherein the head elements of the second hook elements comprise ferromagnetic or paramagnetic particles dispersed in a carrier fluid,

wherein the particles are selected from the group consisting of iron, iron alloys, iron oxides, iron nitride, iron carbide, carbonyl iron, nickel, cobalt, chromium dioxide, stainless steel, silicon steel, and combinations comprising at least one of the foregoing;

and

wherein the carrier fluid is selected from the group consisting of silicone oils, mineral oils, paraffin oils, silicone copolymers, white oils, hydraulic oils, transformer oils, halogenated paraffins, perfluorinated polyethers and fluorinated hydrocarbons, diesters, polyoxyalkylenes, fluorinated silicones, cyanoalkyl siloxanes, glycols, synthetic hydrocarbon oils, and combinations comprising at least one of the foregoing fluids.

9. The releasable fastener system of claim 1, wherein the head elements of the second hook elements comprise ferromagnetic or paramagnetic particles in poly-alpha-olefins, natural rubber, silicone, polybutadiene, polyethylene, polyisoprene, or combinations comprising at least one of the foregoing polymeric materials.

10. The releasable fastener system of claim 1, wherein the head elements of the second hook elements comprise a magnetic material based on iron, nickel, cobalt, alloys of the foregoing, or combinations comprising at least one of the foregoing.

11. The releasable fastener system of claim 1, wherein the head elements of the first hook elements comprise a material adapted to change a directional orientation of the head elements of the first hook elements upon receipt of a magnetic signal.

12. The releasable fastener system of claim 11, wherein the magnetic signal comprises a magnetic field oriented in a direction to effectuate a change in the directional orientation of the head elements of the first and second hook elements by rotating the head elements of the first and second hook elements substantially in an x-plane.

13. The releasable fastener system of claim 12, wherein the change in the directional orientation of the head elements of the first and second hook elements reduces a shear force and/or pull-off force.

14. The releasable fastener system of claim 12, wherein the change in the directional orientation of the head elements of the first and second hook elements increases a shear force and/or pull-off force.

15. A process for operating a releasable fastener system, the process comprising:

contacting a first portion to a second portion to form a releasable engagement,

wherein the first portion comprises a first support and a plurality of first hook elements disposed on a surface, wherein the first hook elements comprise head elements at ends of the first hook elements; and

a second portion comprising a second support and a plurality of second hook elements disposed on a surface, wherein the second hook elements comprise head elements at ends of the second hook elements, wherein the head elements of the second hook elements comprise a material adapted to change a directional orientation of the head elements of the second hook elements upon receipt of a magnetic signal;

maintaining constant shear and pull-off forces in the releasable engagement;

selectively introducing the magnetic signal to the head elements of the second hook elements, wherein the magnetic signal is effective to change the directional orientation of the head elements of the second hook elements; and

reducing shear and/or pull-off forces in the releasable engagement.

16. The process according to claim 15, wherein the head elements of the second hook elements comprise a magnetic material, a magnetorheological fluid, a magnetorheological elastomer, or combinations comprising at least one of the foregoing materials.

17. The process according to claim 15, wherein the magnetic signal comprises a magnetic field oriented in a direction to effectuate a change in the directional orientation of the head elements of the second hook elements by rotating the head elements of the second hook elements substantially in an x-plane.

18. The process according to claim 15, wherein the head elements of the first hook elements comprise a material adapted to change a directional orientation of the head elements of the first hook elements upon receipt of a magnetic signal.

19. The process according to claim 15, wherein the magnetic signal comprises a magnetic field oriented in a direction to effectuate a change in the directional orientation of the head elements of the first and second hook elements by rotating the head elements of the first and second hook elements substantially in an x-plane.

20. A hook portion for a releasable fastener system comprising:

a support; and

a plurality of hook elements disposed on a surface, wherein the hook elements comprise head elements at ends of the hook elements, and wherein the head elements comprise a material adapted to change a directional orientation of the head elements upon receipt of a magnetic signal.

21. The hook portion according to claim 20, wherein the head elements of the hook elements comprise a magnetic material, a magnetorheological fluid, a magnetorheological elastomer, or combinations comprising at least one of the foregoing materials.

22. The hook portion according to claim 20, wherein the support comprises a metal, a plastic, a fabric, or a combination comprising at least one of the foregoing materials.

23. The hook portion according to claim 20, wherein the magnetic signal is a magnetic field oriented in a direction to effectuate a change in the directional orientation of the head elements by rotation of the head elements substantially in an x-plane.

24. A process for operating a releasable fastener system, the process comprising:

providing a first portion comprising a first support and a plurality of first hook elements disposed on a surface, wherein the first hook elements comprise head elements at ends of the first hook elements;

applying a magnetic signal to a second portion comprising a second support and a plurality of second hook elements disposed on a surface, wherein the second hook elements comprise head elements at ends of the second hook elements, and wherein the head elements at the ends of the second hook elements comprise a material adapted to change a directional orientation of the head elements of the second hook elements upon receipt of a magnetic signal;

contacting the first portion with the second portion; and

discontinuing the magnetic signal to cause the first hook elements and the second hook elements to interlock.

25. A releasable fastener system comprising:

a first portion comprising a first support and a plurality of first hook elements disposed on a surface, wherein the first hook elements comprise head elements at ends of the first hook elements; and

a second portion comprising a second support and a plurality of second hook elements disposed on a surface, wherein the second hook elements comprise head elements at ends of the second hook elements, and wherein the head elements of the second hook elements comprise a material adapted to change a directional orientation of the head elements of the second hook elements upon receipt of a magnetic signal; and

means for changing the directional orientation of the head elements of the second hook elements to reduce a shear force and/or a pull-off force of engaged first hook elements and second hook elements.

26. The releasable fastener system according to claim 25, wherein the first support and the second support are fabricated from an inflexible material.

27. The releasable fastener system according to claim 25, wherein the head elements of the first hook elements comprise a material adapted to change a directional orientation of the head elements of the first hook elements upon receipt of a magnetic signal.

28. The releasable fastener system according to claim 25, wherein the magnetic signal comprises a magnetic field oriented in a direction to effectuate a change in the directional orientation of the head elements of the first and second hook elements by rotating the head elements of the first and second hook elements substantially in an x-plane.