Sensor element

• US 20020167704A1
• Filed: 05/01/2002
• Published: 11/14/2002
• Est. Priority Date: 05/09/2001
• 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: Kleinhans, Andreas, Schilling, Wilfried
• Granted Patent: US 6,664,489 B2
• Time in Patent Office: Days
• US Class Current: 398/175
• CPC Class Codes: H03K 17/962 Capacitive touch switches
• CPC Class Codes: H03K 2217/96076 with spring electrode
• CPC Class Codes: H03K 2217/96079 using a single or more light guides

Abstract

A sensor element and a touch switch arrangement (11, 111) have a sensor surface (12, 112), which engages on the underside (13) of a control surface (114). It is at least partly light-transmitting and is illuminated from below by a LED (17, 117) as the light source. Funnel-shaped, closed light guide means (20) are provided, which guide or conduct the light from the LED (17) to the sensor surface (12) or shield against the environment. The light guide means can additionally have further function such as securing in position or electrical contacting of the sensor surface (12, 112).

Claims

1. Sensor element with a sensor surface being a part of a capacitive touch switch, said sensor surface being fitted to the underside of a control surface of said capacitive touch switch, wherein said sensor surface is at least partly light-transmitting and is illuminated from below by a light source, light guide means being provided for the light flux from said light source to said sensor surface.

2. Sensor element according to claim 1, wherein there is one light source per sensor element.

3. Sensor element according to claim 1, wherein there is one light guide means per sensor element.

4. Sensor element according to claim 1, wherein said light guide means shield said light source of a touch switch against the environment.

5. Sensor element according to claim 4, wherein said light guide means shield said light source of one touch switch against other touch switches.

6. Sensor element according to claim 4, wherein said light guide means shield said light source against the remaining underside of said control surface.

7. Sensor element according to claim 1, wherein said light guide means have a wall, which surrounds said at least one light source and forms a channel to said sensor surface.

8. Sensor element according to claim 7, wherein said channel is closed in a substantially light-proof manner.

9. Sensor element according to claim 1, wherein said light guide means are at least partly constructed as a channel wall for pressing said sensor surface against said underside of said control surface.

10. Sensor element according to claim 9, wherein said light guide means are constructed for elastically pressing said sensor surface against said underside of said control surface.

11. Sensor element according to claim 1, wherein said light guide means form an electrical contacting means on said sensor surface.

12. Sensor element according to claim 1, wherein said light guide means have a reflecting surface.

13. Sensor element according to claim 12, wherein said light guide means have said reflecting surface on the surface facing said light source.

14. Sensor element according to claim 1, wherein said light guide means are made from plastic.

15. Sensor element according to claim 1, wherein said light guide means are flexible.

16. Sensor element according to claim 1, wherein said light source is variable as a function of the switching state of said touch switch.

17. Sensor element according to claim 1, wherein said sensor surface is constructed at least partly in light-transmitting manner for displaying symbols in the illuminated state.

18. Sensor element according to claim 17, wherein said sensor surface has light-transmitting recesses in the form of said symbols to be displayed.

19. Sensor element according to claim 17, wherein said sensor surface has light-transmitting recesses in the form of symbols to be displayed.

20. Sensor element according to claim 1, wherein said light guide means guide light from the light source to said sensor surface in the form of a symbol to be displayed.