Contact switching arrangement
View Patent ↗A contact switching arrangement with a flat electrically non-conducting cover which forms a switching area on a top facing the user, and has an underside facing away from the user, at which at least one electrode is arranged and is connected with a switching arrangement for triggering a contact signal when a finger of the user or a similar conducting body approaches. The cover has a light-reflecting, electrically non-conducting film, at least over portions, which acts as a non-conductor. The contact switching arrangement is for use in connection with control panels of electronic devices, for example.
1. A contact switching arrangement with a flat, electrically non-conducting cover ( 10 ) which forms a switching area ( 14 a , 14 b ) on a top ( 12 ) facing an user and has an underside ( 16 ) facing away from the user, at which at least one electrode ( 18 a , 18 b , 20 a , 20 b ) is arranged and is connected with a switching arrangement ( 22 ) for triggering a contact signal when a finger of the user or a conducting body approaches, the contact switching arrangement comprising:
a light-reflecting, electrically non-conducting film ( 24 ) over at least a portion of the cover, acting as a non-conductor.
2. The contact switching arrangement in accordance with claim 1 , Wherein two lower electrodes ( 18 a and 18 b , 20 a and 20 b ) are arranged next to each other on the underside ( 16 ) of the cover ( 10 ), and an upper electrode ( 26 a , 26 b ) is arranged on the switching area ( 14 a , 14 b ), and have a length that covers the two electrodes ( 18 a and 18 b , 20 a and 20 b ) arranged on the underside ( 16 ), which are wired together as a series connection of two capacitors and are capacitively connected by the upper electrode ( 26 a , 26 b ).
3. The contact switching arrangement in accordance with claim 2 , wherein the upper electrode ( 26 a , 26 b ) is made of a transparent material.
4. The contact switching arrangement in accordance with claim 1 , wherein two electrodes ( 18 a and 18 b , 20 a and 20 b ) are arranged next to each other on the underside ( 16 ) of the cover ( 10 ), which are connected with a switching arrangement ( 22 ) for generating an electrical alternating field ( 28 a , 28 b ) which penetrates the cover ( 10 ) at least near the switching area ( 14 a , 14 b ) and for detecting disturbances of the electrical alternating field ( 28 a , 28 b ) in case of the approach of the finger of the user, or of a similar conducting body, to the switching area ( 14 a , 14 b ).
5. The contact switching arrangement in accordance with claim 1 , wherein the cover is made from the light-reflecting film ( 24 ).
6. The contact switching arrangement in accordance with claim 1 , wherein the cover ( 10 ) is formed of a transparent plate ( 30 ), which has the switching area ( 14 a , 14 b ) on the top ( 12 ) facing the user, and the light-reflecting film ( 24 ) on the underside ( 16 ) facing away from the user.
7. The contact switching arrangement in accordance with claim 1 , wherein the cover ( 10 ) is formed by a non-conducting plate ( 30 ) which has the light-reflecting film ( 24 ) and the switching area ( 14 a , 14 b ) on the top ( 12 ) facing the user.
8. The contact switching arrangement in accordance with claim 1 , wherein the light-reflecting film ( 24 ) has one of a smooth, a mirrored, and a structured surface, which reflects light in a diffuse manner.
9. The contact switching arrangement in accordance with claim 1 , wherein the light-reflecting film ( 24 ) transmits light at least partially in a visible wavelength range.
10. The contact switching arrangement in accordance with claim 9 , wherein at least one illuminated display ( 32 a , 32 b , 32 c ) is arranged on one of the underside ( 16 ) of the cover ( 10 ) and the light-reflecting film ( 24 ) facing away from the user.
11. The contact switching arrangement in accordance with claim 10 , wherein the illuminated displays ( 32 a , 32 b , 32 c ) are formed by at least one of lamps, light-emitting diodes, self-illuminated graphic displays, 7-segment displays, backlit liquid crystal displays, backlit symbols and optical displays radiating though the light-reflecting film.
12. The contact switching arrangement in accordance with claim 1 , wherein the position of the switching area ( 14 a , 14 b ) is identified by at least one of a symbolic device and a similar marking ( 34 a , 34 b , 34 c , 34 d ) on at least one of the cover ( 10 ) and the light-reflecting film ( 24 ).
13. The contact switching arrangement in accordance with claim 1 , wherein the light-reflecting film ( 24 ) is flexible, and the flat cover ( 10 ) at least in some areas is one of curved, angled and has shapes differing from a flat shape, at least in some areas.
14. The contact switching arrangement in accordance with claim 1 , wherein the film ( 24 ) is formed by a multi-layered non-metallic polymer film which reflects light in a mirror-like manner.
15. The contact switching arrangement in accordance with claim 14 , wherein the multi-layered polymer film reflects light at an angle of incidence of 0° to 90°.
16. The contact switching arrangement in accordance with claim 14 , wherein the multi-layered polymer film reflects more than 95% of visible light in a wave range of lambda=400 nm to 700 nm.
17. The contact switching arrangement in accordance with claim 16 , wherein the multi-layered polymer film reflects light at an angle of incidence of 0° to 90°.
18. The contact switching arrangement in accordance with claim 17 , wherein two electrodes ( 18 a and 18 b , 20 a and 20 b ) are arranged next to each other on the underside ( 16 ) of the cover ( 10 ), which are connected with a switching arrangement ( 22 ) for generating an electrical alternating field ( 28 a , 28 b ) which penetrates the cover ( 10 ) at least near the switching area ( 14 a , 14 b ) and for detecting disturbances of the electrical alternating field ( 28 a , 28 b ) in case of the approach of the finger of the user, or of a similar conducting body, to the switching area ( 14 a , 14 b ).
19. The contact switching arrangement in accordance with claim 17 , wherein two lower electrodes ( 18 a and 18 b , 20 a and 20 b ) are arranged next to each other on the underside ( 16 ) of the cover ( 10 ), and an upper electrode ( 26 a , 26 b ) is arranged on the switching area ( 14 a , 14 b ), and have a length that covers the two electrodes ( 18 a and 18 b , 20 a and 20 b ) arranged on the underside ( 16 ), which are wired together as a series connection of two capacitors and are capacitively connected by the upper electrode ( 26 a , 26 b ).
20. The contact switching arrangement in accordance with claim 19 , wherein the upper electrode ( 26 a , 26 b ) is made of a transparent material.
21. The contact switching arrangement in accordance with claim 20 , wherein the cover is made from the light-reflecting film ( 24 ).
22. The contact switching arrangement in accordance with claim 21 , wherein the cover ( 10 ) is formed of a transparent plate ( 30 ), which has the switching area ( 14 a , 14 b ) on the top ( 12 ) facing the user, and the light-reflecting film ( 24 ) on the underside ( 16 ) facing away from the user.
23. The contact switching arrangement in accordance with claim 22 , wherein the cover ( 10 ) is formed by a non-conducting plate ( 30 ) which has the light-reflecting film ( 24 ) and the switching area ( 14 a , 14 b ) on the top ( 12 ) facing the user.
24. The contact switching arrangement in accordance with claim 23 , wherein the light-reflecting film ( 24 ) is applied to the transparent plate ( 30 ) by one of a lamination, a heat-seal, an adhesive and a fixed planar connection.
25. The contact switching arrangement in accordance with claim 24 , wherein the transparent plate ( 30 ) is made of one of a glass, a plastic and a transparent material.
26. The contact switching arrangement in accordance with claim 25 , wherein the light-reflecting film ( 24 ) has one of a smooth, a mirrored, and a structured surface, which reflects light in a diffuse manner.
27. The contact switching arrangement in accordance with claim 26 , wherein the light-reflecting film ( 24 ) transmits light at least partially in a visible wavelength range.
28. The contact switching arrangement in accordance with claim 27 , wherein at least one illuminated display ( 32 a , 32 b , 32 c ) is arranged on one of the underside ( 16 ) of the cover ( 10 ) and the light-reflecting film ( 24 ) facing away from the user.
29. The contact switching arrangement in accordance with claim 20 , wherein the illuminated displays ( 32 a , 32 b , 32 c ) are formed by at least one of lamps, light-emitting diodes, self-illuminated graphic displays, 7-segment displays, backlit liquid crystal displays, backlit symbols and optical displays radiating through the light-reflecting film.
30. The contact switching arrangement in accordance with claim 29 , wherein the position of the switching area ( 14 a , 14 b ) is identified by at least one of a symbolic device and a similar marking ( 34 a , 34 b , 34 c , 34 d ) on at least one of the cover ( 10 ) and the light-reflecting film ( 24 ).
31. The contact switching arrangement in accordance with claim 30 , wherein the light-reflecting film ( 24 ) is flexible, and the flat cover ( 10 ) at least in some areas is one of curved, angled and has shapes differing from a flat shape.
32. The contact switching arrangement in accordance with claim 22 , wherein the light-reflecting film ( 24 ) is applied to the transparent plate ( 30 ) by one of a lamination, a heat-seal, an adhesive and a fixed planar connection.
33. The contact switching arrangement in accordance with claim 22 , wherein the transparent plate ( 30 ) is made of one of a glass, a plastic and a transparent material.