Glass membrane touch-controlled circuit apparatus for voltage selection

• US 4,975,676 A
• Filed: 11/13/1989
• Issued: 12/04/1990
• Est. Priority Date: 11/13/1989
• Status: Expired due to Term

• Current Assignee: Spectra Symbol Corp. (Zebra Technologies Corporation)
• Original Assignee: Spectra Symbol Corp. (Zebra Technologies Corporation)
• Inventors: Greenhalgh, Verl B.
• Primary Examiner(s): Reynolds, Bruce A.
• Assistant Examiner(s): Lateef, Marvin M.
• Application Number:
  US07/435,988
• Time in Patent Office: 386 Days
• Field of Search: 338/114, 338/99, 338/71, 338/69, 340/711, 340/712, 200/5 A, 200/86 R
• US Class Current: 338/114
• CPC Class Codes: B66B 1/463 Touch sensitive input devices
• CPC Class Codes: H01C 10/10 adjustable by mechanical pressure or force
• CPC Class Codes: H01H 13/702 with contacts carried by or formed from layers in a multilayer structure, e.g. membrane switches
• CPC Class Codes: H01H 13/703 characterised by spacers between contact carrying layers
• CPC Class Codes: H01H 2209/016 Protection layer, e.g. for legend, anti-scratch
• CPC Class Codes: H01H 2209/084 Glass
• CPC Class Codes: H01H 2211/01 Ink
• CPC Class Codes: H01H 2219/028 Printed information
• CPC Class Codes: H01H 2227/002 Layer thickness
• CPC Class Codes: H01H 2227/03 Hardness
• CPC Class Codes: H01H 2239/02 Other elements in moving part

Abstract

A glass membrane touch-controlled circuit apparatus for voltage selection. The apparatus has a flexible glass membrane which is spaced by a dielectric layer adhesively joined between the upper flexible glass membrane and a lower, rigid support layer. Conductive circuitry is printed onto the surface of the upper flexible glass membrane and corresponding areas of conductive and/or resistive circuitry are printed onto the lower support layer. By application of tactile pressure to the upper flexible glass membrane, the conductive circuitry printed onto the flexible glass membrane can be moved into a point of momentary contact with the circuitry carried on the lower support layer.

Claims

1. A membrane-type electrical control panel apparatus for activating electrical contact between a first and a second electrical circuit means by flexible movement of one of said circuit means in relation to the other in response to tactile pressure exerted on said membrane-type control panel apparatus, said apparatus comprising:

a flexible membrane means for activating electrical contact between said first and second circuit means in response to tactile pressure exerted on said membrane means, said membrane means comprising one of said circuit means and a continuous topmost glass layer having sufficient flexibility to permit flexible movement of said glass layer together with said one circuit means to a point of electrical contact with the other said circuit means when said tactile pressure is applied to said glass layer, and said glass layer having sufficient elasticity to permit said glass layer together with said one circuit means to return to a point of non-electrical contact with the other said circuit means when said tactile pressure is removed from said glass layer;

support layer means for holding said other circuit means stationary; and

spacer means for spacing said flexible membrane means from said support layer means so as to prevent electrical contact between said first and second circuit means until said tactile pressure is exerted.

2. An apparatus as defined in claim 1 wherein said flexible membrane means further comprises a polyester layer adhesively joined at one surface thereof to said glass layer, and wherein said one circuit means is carried by another surface of said polyester layer which is opposite to said one surface.

3. An apparatus as defined in claim 2 wherein said support layer means comprises a polyester layer adhesively joined at one surface thereof to an inflexible glass layer, and wherein said other circuit means is carried by another surface of the polyester layer which is opposite to the surface joined to said inflexible glass layer.

4. An apparatus as defined in claim 3 wherein said spacer means comprises a layer of dielectric material adhesively joined between said polyester layers of said membrane means and said support layer means.

5. An apparatus as defined in claim 4 wherein said glass layer of the flexible membrane means has a thickness of between 5 to 24 mils, wherein each said polyester layer is approximately 5 mils thick, wherein said layer of dielectric material is approximately 1 to 3 mils thick, and wherein said inflexible glass layer is approximately one eighth inch thick.

6. A apparatus as defined in claim 2 wherein said support layer means comprises an inflexible glass layer and wherein said spacer means comprises a layer of dielectric material adhesively joined between said inflexible glass layer and said polyester layer.

7. An apparatus as defined in claim 6 wherein said glass layer of the flexible membrane means has a thickness of between 5 to 24 mils, wherein each said polyester layer is approximately 5 mils thick, wherein said layer of dielectric material is approximately 1 to 3 mils thick, and wherein said inflexible glass layer is approximately one eighth inch thick.

8. An apparatus as defined in claim 1 wherein said support layer means comprises an inflexible glass layer and wherein said spacer means comprises a layer of dielectric material adhesively joined between said inflexible glass layer and said glass layer of the flexible membrane means.

9. An apparatus as defined in claim 8 wherein said glass layer of the flexible membrane means has a thickness of between 5 to 24 mils, wherein said layer of dielectric material is approximately 1 to 3 mils thick, and wherein said inflexible glass layer is approximately one eighth inch thick.

10. An apparatus as defined in claim 2 wherein said flexible membrane means further comprises a layer of graphic printing interposed between said polyester layer and said glass layer, said graphic printing defining one or more areas intended for receiving said tactile pressure to activate electrical contact between said first and second circuit means, and said glass layer being optically clear to permit visual perception of said layer of graphic printing.

11. An apparatus as defined in claim 1 wherein said flexible membrane means further comprises a layer of graphic printing placed on an upper surface of said glass layer, said graphic printing defining one or more areas intended for receiving said tactile pressure to activate electrical contact between said first and second circuit means.

12. An apparatus as defined in claim 1 wherein said flexible membrane means further comprises a layer of graphic printing interposed between said one circuit means and said glass layer, said graphic printing defining one or more areas intended for receiving said tactile pressure to activate electrical contact between said first and second circuit means, and said glass layer being optically clear to permit visual perception of said layer of graphic printing.

13. An apparatus as defined in claim 1 wherein said glass layer comprises a borasilicate material which can withstand continuous temperatures up to 150°

C. without causing deformation of said glass layer, which can withstand temperatures of up to approximately 300°

C. for up to five seconds without causing said deformation, and which has a minimum Knoop hardness of approximately 650,000 psi.

14. An apparatus as defined in claim 1 wherein said first and second electrical circuit means each comprise a thin-film tracing of electrically conductive material with corresponding portions thereof formed as on-off tactile switch areas.

15. An apparatus as defined in claim 1 wherein one of said first and second electrical circuit means comprises an area containing a thin-film tracing of high resistance material and wherein the other said circuit means comprises a corresponding area containing a thin-film tracing of electrically conductive material so as to form an electrical potentiometer when one area contacts the other.

16. A membrane-type electrical control panel apparatus comprising:

a thin, flexible glass layer having a continuous outer activation surface on which tactile pressure is exerted, and a continuous inner, enclosed surface;

a first thin-film circuit means for defining a first plurality of electrical contact areas which can be selectively activated by application of said tactile pressure to areas of said outer activation surface corresponding to said contact areas, said first circuit means being carried on said inner, enclosed surface of the flexible glass layer;

a support layer having an inner, enclosed surface which faces the inner, enclosed surface of said flexible glass layer;

a second thin-film circuit means for defining a second plurality of electrical contact areas, said second circuit means being carried on said inner, enclosed surface of said support layer such that each area of said second plurality of electrical contact areas is positioned for electrical contact by one of said first plurality of electrical contact areas, thereby forming a plurality of pairs of the corresponding areas defined by said first and second circuit means; and

a dielectric layer interposed between the inner, enclosed surfaces of said flexible glass layer and said support layer, said dielectric layer serving to space said first and second plurality of contact areas one from the other so that electrical contact occurs only in response to said tactile pressure, and wherein said glass layer is sufficiently flexible to permit movement of said first circuit means into electrical contact with said second circuit means at any of said electrical contact areas at which said tactile pressure is applied, and said glass layer having sufficiently elasticity to permit return of said first circuit means to a spaced position of nonelectrical contact with respect to said second circuit means when said tactile pressure is removed.

17. An apparatus as defined in claim 16 further comprising a layer of graphic printing interposed between said first circuit means and the inner, enclosed surface of said flexible glass layer, said layer of graphic printing defining a plurality of tactile areas corresponding to said first plurality of electrical contact areas defined by said first circuit means, and said flexible glass layer being optically clear to permit visual perception of said tactile areas.

18. An apparatus as defined in claim 16 wherein at least some of said first and second plurality of electrical contact areas are each defined by thin-film conductive material so that each said corresponding pair of electrical contact areas of the first and second circuit means together form an on-off tactile switch.

19. An apparatus as defined in claim 18 wherein at least one of the electrical contact areas of said second circuit means is defined by a high-resistance thin-film material, so that at least one electrical contact area defines an electrical potentiometer that is touch-controlled.

20. An apparatus as defined in claim 16 wherein said glass layer comprises a borasilicate material which can withstand continuous temperatures up to 150°

C. without causing deformation of said glass layer, which can withstand temperatures of up to approximately 300°

C. for up to five seconds without causing said deformation, and which has a minimum Knoop hardness of approximately 650,000 psi.

21. An apparatus as defined in claim 20 wherein said glass layer has a thickness between 5 and 24 mils.

22. An apparatus as defined in claim 21 wherein said support layer comprises a layer of inflexible glass having a thickness of approximately one eighth inch.

23. An apparatus as defined in claim 21 wherein said support layer comprises a layer of stainless steel.

24. An apparatus as defined in claim 21 wherein said dielectric layer is approximately 1 to 3 mils thick.

25. An apparatus as defined in claim 16 wherein said first circuit means comprises a polyester layer adhesively joined at one surface thereof to said thin flexible glass layer at the inner enclosed surface thereof, and wherein said first plurality of electrical contact areas is deposited on another surface of said polyester layer which is opposite to said one surface.

26. An apparatus as defined in claim 25 further comprising a layer of graphic printing interposed between said first circuit means and the inner, enclosed surface of said flexible glass layer, said layer of graphic printing defining a plurality of tactile areas corresponding to said first plurality of electrical contact areas defined by said first circuit means, and said flexible glass layer being optically clear to permit visual perception of said tactile areas.

27. An apparatus as defined in claim 26 wherein said dielectric layer is adhesively joined to the same surface as said first thin-film circuit means.

28. An apparatus as defined in claim 27 wherein said second thin-film circuit means comprises a polyester layer adhesively joined at one surface thereof to said inner enclosed surfaced of said support layer, and wherein said second plurality of electrical contact areas is deposited on another surface of the second polyester layer which is opposite to the surface of the second polyester layer joined to the inner enclosed surface of the support layer.

29. An apparatus as defined in claims 27 or 28 wherein at least same of said first and second plurality of electrical contact areas are each defined by thin-film conductive material so that each said corresponding pair of electrical contact areas of the first and second circuit means together form an on-off tactile switch.

30. An apparatus as defined in claim 29 wherein at least one of the electrical contact areas of said second circuit means is defined by a high-resistance thin-film material, so that at least one electrical contact area defines an electrical potentiometer that is touch-controlled.

31. A membrane-type electrical control panel apparatus comprising:

a thin, flexible glass layer having a continuous outer activation surface on which tactile pressure is exerted, and an inner, enclosed surface;

a first thin-film circuit defining a first plurality of electrical contact areas which can be selectively activated by application of said tactile pressure to areas of said outer activation surface corresponding to said contact areas, said first plurality of electrical contact areas being carried on said inner, enclosed surface of the flexible glass layer;

a support layer having an inner, enclosed surface which faces the inner, enclosed surface of said flexible glass layer;

a second thin-film circuit defining a second plurality of electrical contact areas, said second plurality of electrical contact areas being carried on said inner, enclosed surface of said support layer such that each area of said second plurality of electrical contact areas is positioned for electrical contact by one of said first plurality of electrical contact areas, thereby forming a plurality of pairs of the corresponding areas defined by said first and second circuit means; and

a dielectric layer adhesively held between the inner, enclosed surfaces of said flexible glass layer and said support layer, said dielectric layer serving to space said first and second plurality of contact areas one from the other so that electrical contact occurs only in response to said tactile pressure, and wherein said glass layer is sufficiently flexible to permit movement of said first circuit into electrical contact with said second circuit at any of said electrical contact areas at which said tactile pressure is applied, and said glass layer having sufficiently elasticity to permit return of said first circuit to a spaced position of non-electrical contact with respect to said second circuit when said tactile pressure is removed.

32. An apparatus as defined in claim 31 further comprising a layer of graphic printing interposed between said first circuit and the inner, enclosed surface of said flexible glass layer, said layer of graphic printing defining a plurality of tactile areas corresponding to said first plurality of electrical contact areas defined by said first circuit, and said flexible glass layer being optically clear to permit visual perception of said tactile areas.

33. An apparatus as defined in claim 32 wherein at least some of said first and second plurality of electrical contact areas are each defined by thin-film conductive material so that each said corresponding pair of electrical contact areas of the first and second circuits together form an on-off tactile switch.

34. An apparatus as defined in claim 33 wherein at least one of the electrical contact areas of said second circuit is defined by a high-resistance thin-film material, so that at least one electrical contact area defines an electrical potentiometer that is touch-controlled.

35. A membrane-type electrical control panel apparatus comprising:

a thin, flexible glass layer having a continuous outer activation surface on which tactile pressure is exerted, and a continuous inner, enclosed surface;

a first polyester layer adhesively joined at one surface thereof to said inner enclosed surface of the thin flexible glass layer;

a first thin-film circuit defining a first plurality of electrical contact areas which can be selectively activated by application of said tactile pressure to areas of said outer activation surface corresponding to said contact areas, said first plurality of electrical contact areas being carried on another surface of said first polyester layer that is opposite to said one surface of said polyester layer;

a support layer having an inner, enclosed surface which faces the inner, enclosed surface of said flexible glass layer;

a second thin-film circuit defining a second plurality of electrical contact areas, said second plurality of electrical contact areas being carried on said inner, enclosed surface of said support layer such that each area of said second plurality of electrical contact areas is positioned for electrical contact by one of said first plurality of electrical contact areas, thereby forming a plurality of pairs of the corresponding areas defined by said first and second circuit means; and

a dielectric layer interposed between the inner, enclosed surfaces of said flexible glass layer and said support layer, said dielectric layer serving to space said first and second plurality of contact areas one from the other so that electrical contact occurs only in response to said tactile pressure, and wherein said glass layer is sufficiently flexible to permit movement of said first circuit into electrical contact with said second circuit at any of said electrical contact areas at which said tactile pressure is applied, and said glass layer having sufficiently elasticity to permit return of said first circuit to a spaced position of non-electrical contact with respect to said second circuit when said tactile pressure is removed.

36. An apparatus as defined in claim 35 further comprising a layer of graphic printing interposed between said first circuit and the inner, enclosed surface of said flexible glass layer, said layer of graphic printing defining a plurality of tactile areas corresponding to said first plurality of electrical contact areas defined by said first circuit, and said flexible glass layer being optically clear to permit visual perception of said tactile areas.

37. An apparatus as defined in claim 36 wherein at least some of said first and second plurality of electrical contact areas are each defined by thin-film conductive material so that each said corresponding pair of electrical contact areas of the first and second circuits together form an on-off tactile switch.

38. An apparatus as defined in claim 37 wherein at least one of the electrical contact areas of said second circuit is defined by a high-resistance thin-film material, so that at least one electrical contact area defines an electrical potentiometer that is touch-controlled.

39. A membrane-type electrical control panel apparatus comprising:

a thin, flexible glass layer having a continuous outer activation surface on which tactile pressure is exerted, and a continuous inner, enclosed surface;

a first polyester layer adhesively joined at one surface thereof to said inner enclosed surface of the thin flexible glass layer;

a first thin-film circuit defining a first plurality of electrical contact areas which can be selectively activated by application of said tactile pressure to areas of said outer activation surface corresponding to said contact areas, said first plurality of electrical contact areas being carried on another surface of said first polyester layer that is opposite to said one surface of said first polyester layer;

a support layer having an inner, enclosed surface which faces the inner, enclosed surface of said flexible glass layer;

a second polyester layer adhesively joined at one surface thereof to the inner enclosed surface of said support layer;

a second thin-film circuit defining a second plurality of electrical contact areas, said second plurality of electrical contact areas being carried on another surface of said second polyester layer that is opposite to said one surface of the second polyester layer such that each area of said second plurality of electrical contact areas is positioned for electrical contact by one of said first plurality of electrical contact areas, thereby forming a plurality of pairs of the corresponding areas defined by said first and second circuits; and

a dielectric layer interposed between the inner, enclosed surfaces of said flexible glass layer and said support layer, said dielectric layer serving to space said first and second plurality of contact areas one from the other so that electrical contact occurs only in response to said tactile pressure, and wherein said glass layer is sufficiently flexible to permit movement of said first circuit into electrical contact with said second circuit at any of said electrical contact areas at which said tactile pressure is applied, and said glass layer having sufficiently elasticity to permit return of said first circuit to a spaced position of non-electrical contact with respect to said second circuit when said tactile pressure is removed.

40. An apparatus as defined in claim 39 further comprising a layer of graphic printing interposed between said first circuit and the inner, enclosed surface of said flexible glass layer, said layer of graphic printing defining a plurality of tactile areas corresponding to said first plurality of electrical contact areas defined by said first circuit, and said flexible glass layer being optically clear to permit visual perception of said tactile areas.

41. An apparatus as defined in claim 40 wherein at least some of said first and second plurality of electrical contact areas are each defined by thin-film conductive material so that each said corresponding pair of electrical contact areas of the first and second circuits together form an on-off tactile switch.

42. An apparatus as defined in claim 41 wherein at least one of the electrical contact areas of said second circuit is defined by a high-resistance thin-film material, so that at least one electrical contact area defines an electrical potentiometer that is touch-controlled.