Flexible touch-sense switch

• US 20050275567A1
• Filed: 06/09/2004
• Published: 12/15/2005
• Est. Priority Date: 06/09/2004
• Status: Active Grant

• Current Assignee: Lear Corporation
• Original Assignee: Lear Corporation
• Inventors: Hein, David A., DePue, Todd L.
• Granted Patent: US 7,091,886 B2
• Time in Patent Office: Days
• US Class Current: 341/32
• CPC Class Codes: H03K 17/94 characterised by the way in which the control signals are generated
• CPC Class Codes: H03K 17/9502 Measures for increasing reliability
• CPC Class Codes: H03K 17/955 using a capacitive detector
• CPC Class Codes: H03K 17/9625 using a force resistance transducer
• CPC Class Codes: H03K 17/964 Piezoelectric touch switches
• CPC Class Codes: H03K 2217/94047 Cascode connected switches
• CPC Class Codes: H03K 2217/960705 Safety of capacitive touch and proximity switches, e.g. increasing reliability, fail-safe

Abstract

A flexible touch-sense switch includes a force sensitive composite and an at least one proximity sensor. The force sensitive composite includes a plurality of force sensors disposed between a first layer and a second layer of polymide film defining a displacement region. The at least one proximity sensor generates an electromagnetic field that defines a detection region. The force sensitive composite and the at least one proximity sensor are mounted to the first layer of the polymide film for forming a flexible printed circuit board. A control circuit is electrically connected to the force sensitive composite and the at least one proximity sensor for selectively controlling the touch-sense switch activation in response to coincident actuation thereof.

Claims

1. A flexible touch-sense switch comprising:

a force sensitive composite including at least one force sensor disposed between a first layer and a second layer of polymide film defining a displacement region;

an at least one proximity sensor for generating an electromagnetic field defining a detection region; and

a control circuit electrically connected to said force sensitive composite and said at least one proximity sensor for selectively controlling touch-sense switch activation in response to coincident actuation thereof;

wherein said force sensitive composite and said at least one proximity sensor are mounted to said first layer of said polymide film for forming a flexible printed circuit board.

2. The flexible touch-sense switch of claim 1 wherein said at least one proximity sensor and said force sensitive composite cooperatively activate said touch-sense switch in response to a potential variation of said detection region and a deflection in said displacement region.

3. The flexible touch-sense switch of claim 1 wherein said force sensitive composite includes a fiber composite and said at least one force sensor includes a plurality of piezo-fibers.

4. The flexible touch-sense switch of claim 1 wherein a flex circuit electrically connects said force sensitive composite and said at least one proximity sensor to said control circuit for transmitting signals.

5. The flexible touch-sense switch of claim 1 wherein said control circuit outputs a voltage signal to said force sensitive composite for generating a tactile feedback in response to said deflection and said potential variation.

6. The flexible touch-sense switch of claim 1 wherein said control circuit outputs a voltage signal to said force sensitive composite for generating an audible feedback in response to said deflection and said potential variation.

7. The flexible touch-sense switch of claim 1 wherein said control circuit outputs a voltage signal to said force sensitive composite for generating a tactile feedback and an audible feedback in response to said deflection and said potential variation.

8. The flexible touch-sense switch of claim 1 further comprising a substrate including a first surface and a second surface, said first layer of polymide film is disposed on said first surface of said substrate.

9. The flexible touch-sense switch of claim 8 further comprising graphical elements printed on said second surface of said substrate.

10. A control panel including a plurality of flexible touch-sense switches comprising:

an at least one force sensitive composite including a plurality of force sensors disposed between a first layer and a second layer of polymide film forming a plurality of displacement regions;

a plurality proximity sensors for generating a plurality of electromagnetic fields define respective detection regions;

wherein said at least one force sensitive composite and said plurality of proximity sensors are disposed on said first layer of said polymide film for forming said plurality of flexible touch-sense switches; and

wherein a respective portion of proximity sensors and an associated force sensitive composite cooperatively activate a respective flexible touch-sense switch in response to a potential variation of said respective detection region coincident with a deflection of a respective displacement region.

11. The control panel of claim 10 wherein a control circuit outputs a voltage signal to said associated force sensitive composite for generating a tactile feedback in response to said deflection and said potential variation.

12. The control panel of claim 10 wherein said at least one force sensitive composite includes at least one fiber composite and said plurality of force sensors includes a plurality of piezo-fibers.

13. The control panel of claim 10 wherein said control circuit outputs a voltage signal to said at least one force sensitive composite for generating an audible feedback in response to said deflection and said potential variation.

14. The control panel of claim 10 wherein said control circuit outputs a voltage signal to said at least one force sensitive composite for generating a tactile feedback and an audible feedback in response to said deflection and said potential variation.

15. The control panel of claim 10 further comprising a substrate including a first surface and a second surface, said first layer of polymide film is disposed on said first surface of said substrate.

16. The flexible touch-sense switch of claim 15 further comprising graphical elements printed on said second surface of said substrate.

17. A method for activating a flexible touch-sense switch, the method comprising the steps of:

providing a force sensitive composite for defining a displacement region, said force sensitive composite including a plurality of force sensors disposed between a first layer and a second layer of polymide film;

arranging at least one proximity sensor on said first layer of polymide film, said at least one proximity sensor generates an electromagnetic field defining a detection region; and

activating said touch-sense switch in response to a potential variation in said detection region coincident with a deflection of said displacement region.

18. The method of claim 17 further comprising the step of providing an output signal to said force sensitive composite for generating a tactile feedback in response to said deflection and said potential variation.

19. The method of claim 17 wherein said first polymide layer is mounted to a first surface of a substrate.

20. The method of claim 17 further comprising the step of creating graphical elements on a second surface of said substrate.