Sensor element device for a capacitive contact switch with an electrically conductive body and method for the manufacture of such a body

• US 20040084970A1
• Filed: 10/20/2003
• Published: 05/06/2004
• Est. Priority Date: 10/31/2002
• Status: Active Grant

• Current Assignee: EGO Elektro-Gerã¤Tebau GmbH (EGO Blanc und Fischer & Company GmbH)
• Original Assignee: EGO Elektro-Gerã¤Tebau GmbH (EGO Blanc und Fischer & Company GmbH)
• Inventors: Schilling, Wilfried, Winkler, Uwe
• Granted Patent: US 7,114,402 B2
• Time in Patent Office: Days
• US Class Current: 307/125
• CPC Class Codes: H03K 17/962 Capacitive touch switches
• CPC Class Codes: H03K 2017/9602 characterised by the type or shape of the sensing electrodes
• CPC Class Codes: H03K 2217/96076 with spring electrode

Abstract

According to an embodiment of the invention, a sensor element device for a capacitive contact switch can be formed from a foam body with several portions. There are electrically conductive areas with a sensor element surface and an electrical contact face, as well as insulating areas. The sensor element surfaces engage from below on a glass ceramic plate. The areas can be interconnected in cylindrically elongated and juxtaposed manner. This leads to a type of strand material from which with the predetermined spacing it is possible to produce juxtaposed, capacitive sensor elements as parts of contact switches.

Claims

1. Sensor element device for a capacitive contact switch, in which said sensor element device has a three-dimensional shape-variable, elastic, compressible body, wherein said body is at least zonally electrically conductive, wherein said sensor element device has an electrical contact zone for contact to a control and a sensor element surface, wherein said body extends from said electrical contact zone to said sensor element surface and has different areas, wherein one of said areas is a conductive area being electrically conductive throughout between said electrical contact zone and said sensor element surface, and another of said areas is an insulating area not being electrically conductive, wherein there is at least one said insulating area between several of said conductive areas.

2. Sensor element device according to claim 1, wherein said sensor element surface is formed by a surface of part of one of said conductive areas.

3. Sensor element device according to claim 2, wherein said sensor element device engages with a cover, wherein said sensor element surface is formed by a contact face between part of said conductive area and said cover.

4. Sensor element device according to claim 1, wherein said conductive areas and said at least one insulating area are mechanically interconnected.

5. Sensor element device according to claim 4, wherein said conductive areas are in one piece.

6. Sensor element device according to claim 1, wherein in an extension direction from said electrical contact zone to said sensor element surface said conductive areas run in roughly said same extension direction.

7. Sensor element device according to claim 6, wherein all said areas of said sensor element including said insulating areas run in said same extension direction.

8. Sensor element device according to claim 6, wherein said areas, considered in said extension direction, are elongated and have a longer extension in said extension direction than in another direction at right angles thereto.

9. Sensor element device according to claim 1, wherein said body is made from a rubbery material.

10. Sensor element device according to claim 9, wherein said rubbery material is made conductive with inclusions.

11. Sensor element device according to claim 1, wherein said body is part of a strand, an extension direction of said areas being perpendicular to a longitudinal direction of said strand.

12. Sensor element device according to claim 11, wherein said strand in a basic state, in said longitudinal direction, is linear and is bendable in a direction at right angles to an extension direction of said areas.

13. Sensor element device according to claim 1, wherein said areas form a bank-like body extended in areal manner perpendicular to an extension direction, said conductive and said insulating areas being arranged in alternating manner in both extensions of said body.

14. Sensor element device according to claim 13, wherein said conductive areas are separated from one another in each direction.

15. Sensor element device according to claim 13, wherein in a direct connection between two mutually closest of said conductive areas is provided an insulating area or an air gap.

16. Sensor element device according to claim 1, wherein said body is cuttable or separable to size at junction points of two said areas.

17. Sensor element device according to claim 1, wherein said electrical contact zone has contacts and said contacts at least have a mutual spacing of two said conductive areas.

18. Sensor element device according to claim 17, wherein several of said conductive areas are located between two mutually closest contacts.

19. Sensor element device according to claim 1, wherein one of said conductive areas is provided on a side directed towards said electrical contact zone with an insulating coating, said electrical contact zone having elongated and upwardly projecting contact pins pushing through said insulating coating in said conductive area in order to produce said electrical contact zone.

20. Sensor element device according to claim 1, wherein an insulating area forms a dielectric between two of said conductive areas in such a way that transverse capacitances or capacitive connections are formed between the said e conductive areas.

21. Sensor element device according to claim 1, wherein one if said conductive areas is completely enveloped by one or more insulating areas in a lateral direction at right angles to its extension direction.

22. Method for the manufacture of a body as a sensor element for a capacitive sensor element device, said body forming said sensor element, wherein conductive areas are formed made from electrically conductive, three-dimensional shape-variable, elastic, compressible material and said conductive areas are linked by insulating areas made from three-dimensional shape-variable, elastic, compressible, insulating material.

23. Method according to claim 22, wherein said connection takes place by adhesion.

24. Method according to claim 22, wherein a strand in a direction of said extension of conductive and insulating areas in juxtaposed form is made much longer than said body and individual of said bodies are produced by separation.