Method and apparatus for providing a touch screen

• US 5,327,164 A
• Filed: 03/12/1993
• Issued: 07/05/1994
• Est. Priority Date: 03/17/1992
• Status: Expired due to Term

• Current Assignee: Sextant Avionique
• Original Assignee: Sextant Avionique
• Inventors: Fagard, Pierre, Coppin, Jean-Marc, Nigen, Claude, Caugant, Xavier
• Primary Examiner(s): Oberley, Alvin E.
• Assistant Examiner(s): Liang, Regina
• Application Number:
  US08/031,635
• Time in Patent Office: 480 Days
• Field of Search: 340/712, 340/707, 340/708, 340/706, 340/709, 340/718, 340/784.1, 178/18, 178/19, 341/33, 341/34, 341/22, 361/398, 361/174, 361/254, 361/268, 200/512, 200/518, 177/229, 439/65, 439/67, 345/173, 345/174, 345/156, 345/179, 345/182, 345/184, 345/178, 345/341, 345/361, 345/200, 345/177, 345/439
• US Class Current: 345/174
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• CPC Class Codes: G06F 3/0444 using a single conductive element covering the whole sensing surface, e.g. by sensing the electrical current flowing at the corners
• CPC Class Codes: H03K 17/94 characterised by the way in which the control signals are generated
• CPC Class Codes: H03K 17/962 Capacitive touch switches

Abstract

A process and device for providing and fixing a captor of activation detection. The present invention discloses a tactile designation device for continuous capacitance detection comprising a glass plate covered by a metallic deposit on its entire surface and supported by flexible strips, means of supply of the metallized surface, and strain gauges mounted on top of the strips in order to measure their flexing. According to the present invention, the strips support the plate from a printed circuit of assembly. Each strip comprises at least one conducting part in contact, at one of its ends, with a supply track formed by the printed circuit, and at its other end, with the attachment devices of the plate on the strip that is electrically conducting and in contact with the metallized surface.

Claims

1. A tactile designation device for continuous capacitance detection comprising a glass plate covered with a metallic deposit on its entire surface, said tactile designation device is supported by flexible strips, by means of supply to said metallic surface and by strain gauges set up on said strips in order to measure flexing of said strips, said tactile designation device characterized by the fact that said strips support said plate from a printed circuit of assembly, each of said strips carrying at least one conducting part, each of said strips having a first end that is in contact with a supply track formed on said printed circuit, each of said strips having a second end that is in contact with attachment devices of said plate on said strip that is electronically conducting and in contact with said metallized surface.

2. The device according to claim 1 wherein said strips have a fork shape at their ends of attachment to said plate, said attachment devices comprising a nut having an exterior shape of a diabolo whose tightened part is fitted into said fork.

3. The device according to any of the claims 1 and 2 wherein said strips have a triangular shape at their flexing points.

4. The device according to any one of the claims 1-2 comprising four flexible strips and four strain gauges, said four flexible strips being arranged in a manner so that two gauges work by compression and two gauges work by traction.

5. The device according to claim 4 wherein said strain gauges are assembled in a Wheatstone bridge.

6. The device according to claim 5 wherein said strain gauges are connected to said printed circuit.

7. The device according to claim 3 comprising four flexible strips and four strain gauges, said four flexible strips being arranged in a manner so that two gauges work by compression and two gauges work by traction.

8. The device according to claim 7 wherein said strain gauges are assembled in a Wheatstone bridge.

9. The device according to any of the claims 1-2 wherein said strain gauges are connected to said printed circuit.

10. The device according to claim 3 wherein said strain gauges are connected to said printed circuit.

11. The device according to claim 4 wherein said strain gauges are connected to said printed circuit.

12. The device according to claim 7 wherein said strain gauges are connected to said printed circuit.

13. The device according to claim 8 wherein said strain gauges are connected to said printed circuit.