Keyboard switch assembly having movable contact, and supporting helicline type legs disposed co-planar to common conductive sheet

• US 3,968,336 A
• Filed: 09/23/1974
• Issued: 07/06/1976
• Est. Priority Date: 09/23/1974
• Status: Expired due to Term

• Current Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Original Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Inventors: Johnson, Wendell C.
• Primary Examiner(s): Scott, James R.
• Application Number:
  US05/508,480
• Time in Patent Office: 652 Days
• Field of Search: 200/5 R, 200/5 A, 200/67 D-67 DB, 200/159 R, 200/159 A, 200/159 B, 200/275, 200/276, 200/83 B, 200/83 N, 200/243, 200/DIG. 1, 200/292, 335/196
• US Class Current: 200/5.00A
• 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 13/785 characterised by the material of the contacts, e.g. conductive polymers
• CPC Class Codes: H01H 13/80 characterised by the manner of cooperation of the contacts, e.g. with both contacts movable or with bounceless contacts
• CPC Class Codes: H01H 13/807 characterised by the spatial arrangement of the contact sites, e.g. superimposed sites
• CPC Class Codes: H01H 2201/004 Wiping action
• CPC Class Codes: H01H 2201/03 Composite
• CPC Class Codes: H01H 2205/006 mounted on spacer
• CPC Class Codes: H01H 2205/01 mounted on flap cut out and bend out of layer
• CPC Class Codes: H01H 2205/032 Several contacts formed in one plate or layer
• CPC Class Codes: H01H 2205/036 Helicoidal cuts
• CPC Class Codes: H01H 2215/004 Collapsible dome or bubble
• CPC Class Codes: H01H 2215/028 alterable
• CPC Class Codes: H01H 2215/04 Contact making part moved through contact supporting plane
• CPC Class Codes: H01H 2225/002 superimposed
• CPC Class Codes: H01H 2227/018 Printed contacts; Metal foil
• CPC Class Codes: H01H 2229/016 Selective etching
• CPC Class Codes: H01H 2229/05 Forming; Half-punching
• CPC Class Codes: H01H 2229/06 Tempering
• CPC Class Codes: H01H 2239/006 Containing a capacitive switch or usable as such
• CPC Class Codes: Y10T 29/49105 Switch making
• CPC Class Codes: Y10T 29/49218 : with deforming
• CPC Class Codes: Y10T 29/49222 : forming array of contacts or terminals

Abstract

A switching device having a movable contact element characterized by a set of unconnected, curved slots radiating outward from a central key area and equally spaced around the central key area. The radially extending unconnected, curved slots may be sections of a spiral, at least some of which sections overlap each other. Adjustment of the spring rate of the movable contact element is accomplished by adjusting the length of the slots or by regulating the distance of the inner terminus of the slots from a central point of the central key area. The movable contact element either contacts a second contact element for contact switching or approaches the second contact element for capacitive switching.

A plurality of the switching elements can be formed in a planar array on a continuous metallic substrate to provide a keyboard. The movable switching elements can be formed on the metallized areas of a printed circuit board.

Claims

1. A switching device comprising:

a first electrically conductive contact member having a plurality of unconnected, curved slots radiating substantially continuously outward from a common portion thereof,

a second electrically conductive contact member having at least a portion thereof positioned in axial alignment with at least a portion of said common portion of said first contact member, and

means for normally separating said first and second contact members but permitting at least said common portion of said first contact member to move toward said aligned portion of said second contact member when a force is applied to said common portion of said first contact member to thereby effect a switching action.

2. The switching device of claim 1 wherein said slots are of equal length.

3. The switching device of claim 1 wherein said slots are sections of a spiral.

4. The switching device of claim 1 wherein said slots have a smooth curve.

5. The switching device of claim 1 wherein each slot is inwardly of the other slots over one portion thereof, outward of the other slots over a second portion thereof, and intermediate the other slots over a third portion thereof.

6. The switching device of claim 1 wherein said common portion touches said second contact member when said force is applied to effect a contact switching action.

7. The switching device of claim 1 wherein a stationary electrically insulating layer is disposed between said common portion and said second contact member such switching action is a capacitive switching action.

8. A switching device comprising:

a first electrically conductive member having at least three curved, unconnected, outwardly radiating slots therein which define a common portion thereof, said at least three slots each having portions which are radially adjacent portions of the other of said at least three slots,

a second electrically conductive contact member having at least a portion thereof positioned in axial alignment with at least a portion of said common portion of said first contact member, and

means for normally separating said first and second contact members but permitting at least said common portion of said first contact member to move toward said aligned portion of said second contact member when a force is applied to said common portion of said first contact member to thereby effect a switching action.

9. The switching device of claim 8 wherein said slots are sections of a spiral.

10. The switching device of claim 8 wherein said slots are of equal length.

11. The switching device of claim 8 wherein said slots have a smooth curve.

12. The switching device of claim 8 wherein substantially only the inner end of each of said slots lies on the circumference of a first circle and substantially only the outer end of each of said slots lies on the circumference of a second circle, said circles being concentric.

13. The switching device of claim 8 wherein substantially only the inner end of each of said slots lies on the circumference of a circle.

14. A keyboard switching device comprising:

a first electrically conductive member having a plurality of planar spring-like patterns formed on separate conductive surfaces thereof, each of said patterns comprising a plurality of unconnected, curved slots radiating continuously outwardly from a common portion thereof,

a plurality of conductive members, at least some of said plurality of conductive members being positioned adjacent at least some different ones of said common portions; and

electrically insulating means for normally separating said adjacent center portions and contact members but permitting each one of said adjacent common portions to effect a switching action when said one common portion is forced from the plane of said first member.

15. A switching device comprising:

a first electrically conductive contact member having a plurality of unconnected, curved slots radiating outwardly from a common portion thereof, each of said slots being inwardly of at least portions of at least two other of said slots over one portion of its length, outward of at least portions of at least two other of said slots over a second portion of its length, and intermediate at least portions of at least two other of said slots over a third portion of its length,

a second electrically conductive contact member having at least a portion thereof positioned in axial alignment with at least a portion of said common portion of said first contact member, and

means for normally separating said first and second contact members but permitting at least said common portion of said first contact member to move toward said aligned portion of said second contact member when a force is applied to said common portion of said first contact member to thereby effect a switching action.

16. A switching device comprising:

an insulating member having a metallic coating over at least a portion of a surface thereof, said coating including a plurality of curved metallic strips which define a movable area of said coating, said strips extending substantially continuously outwardly from said movable area toward a peripheral area of said coating, and

an electrically conductive contact member having at least a portion thereof in axial alignment with at least a portion of said movable area of said coating,

said insulating member having an aperture therein adjacent to said movable area of said coating such that said movable area can be moved through at least a portion of said aperture toward said contact member when a force is applied to said movable area of said coating to thereby effect a switching action.

17. A keyboard for effecting an electrical change upon depression of keys by an operator, comprising:

a plurality of conductive surfaces supported in a common plane by electrically insulating support means, each of said surfaces having a plurality of unconnected, curved slots radiating continuously outward from a common portion thereof;

a contact board positioned adjacent said support means and having a plurality of electrical contacts, at least some of said plurality of contacts in axial alignment with different ones of said common portions;

said electrical insulating support means normally separating said axially aligned electrical contacts from said common portions but permitting each of said common portions to be forcibly moved toward said electrical contact in axial alignment therewith to effect a switching action.

18. A switching device comprising:

an electrically insulating planar substrate having a metallic coating over at least a portion of a surface thereof, said coating having a plurality of unconnected, curved slots radiating substantially continuously outward from a common portion of said coating, and

an electrically conductive contact member having at least a portion thereof positioned in axial alignment with at least a portion of said common portion of said coating,

said insulating substrate having an aperture therein adjacent to said common portion of said coating such that at least said common portion of said coating can be moved through at least a portion of said aperture toward said contact member when a force is applied to said common portion of said coating to thereby effect a switching action.

19. The switching device of claim 18 wherein said slots are sections of a spiral.

20. The switching device of claim 18 wherein said slots are of equal length.

21. The switching device of claim 18 wherein said slots have a smooth curve.

22. The switching device of claim 18 wherein each of said slots is inwardly of at least two other of said slots over one portion of its length and outwardly of at least two other of said slots over another portion of its length.

23. The switching device of claim 18 wherein each of said slots has at least a portion which is radially adjacent at least two other of said slots.

24. The switching device of claim 18 wherein said common portion touches said second contact member when said force is applied to effect a contact switching action.

25. The switching device of claim 18 wherein said second contact member has an electrically insulating layer on the surface thereof facing said common portion such that said switching action is a capacitive switching action.

26. A switching device comprising:

an electrically insulating support substrate having a metallic coating over at least a portion of a surface thereof, said coating having therein at least three slots radiating outwardly from a common portion thereof, the inner ends of said slots defining an equilateral geometric shape and each of said slots extending over an angle of a magnitude such that each of said slots is inwardly of at least a portion of at least two other of said slots over one portion of its length and outwardly of at least a portion of at least two other of said slots over another portion of its length, and

an electrically conductive contact member having at least a portion thereof in axial alignment with at least a portion of said common portion of said coating,

said insulating substrate having an aperture therein adjacent to said common portion of said coating such that at least said common portion can be moved through at least a portion of said aperture toward said contact member when a force is applied to said common portion of said coating to thereby effect a switching action.

27. The switching device of claim 26 wherein said slots are of equal length.

28. The switching device of claim 26 wherein said slots have a smooth curve.

29. The switching device of claim 26 wherein substantially only the inner end of each of said slots lies on the circumference of a circle.

30. The switching device of claim 26 wherein lines joining the inner ends of said slots define an equilateral geometric shape.

31. A keyboard switching device for effecting electrical change upon the depression of a key comprising:

a plurality of key actuating means,

a first substantially planar electrically conductive member having formed therein a first plurality of switching contact members, at least some of said switching members including a group of unconnected, curved slots radiating substantially continuously outwardly from a common portion thereof,

a second plurality of switching contact members, at least one of said second plurality of switching members having at least a portion thereof positioned in operative alignment with at least a portion of one of said plurality of key actuating means and at least a portion of said common portion of one of said first plurality of switching members, and

means for normally separating said first conductive member from said second plurality of switching members but permitting at least said common portion of said one of said first plurality of switching members to move toward said aligned portion of said one of said second plurality of switching members when a force is applied to said one of said plurality of key actuating means to thereby effect a switching action.

32. The switching device of claim 31 wherein said slots are sections of a spiral.

33. The switching device of claim 31 wherein said slots of a group are of equal length.

34. The switching device of claim 31 wherein said slots have a smooth curve.

35. The switching device of claim 31 wherein each of said slots of a group is inwardly of at least two other of said slots of said group over one portion of its length and outwardly of at least two other of said slots of said group over another portion of its length.

36. The switching device of claim 31 wherein substantially only the inner end of each of said slots of a group lies on the circumference of a first circle and substantially only the outer end of each of said slots of a group lies on the circumference of a second circle, said circles being concentric.

37. The switching device of claim 31 wherein substantially only the inner end of each of said slots of a group lies on the circumference of a circle.

38. The switching device of claim 31 wherein lines joining the inner ends of said slots of a group define an equilateral geometric shape.

39. The switching device of claim 31 wherein each of said slots of a group has at least a portion which is radially adjacent at least two other of said slots of said group.

40. The switching device of claim 31 wherein said slots radiate substantially continuously outward.

41. A keyboard switching device for effecting a switching action when a key is depressed comprising:

a plurality of switch actuating means,

a first electrically conductive member having a first plurality of movable switching contacts formed therein, each of said contacts comprised of a group of unconnected, curved slots radiating outwardly from a common portion thereof, each of said slots being inwardly of at least portions of at least two other of said slots over one portion of its length, outward of at least portions of at least two other of said slots over a second portion of its length, and intermediate at least portions of at least two other of said slots over a third portion of its length,

a second plurality of contacts, at least one of said second plurality of contacts having at least a portion thereof positioned in operative alignment with both the common portion of one of said first plurality of contacts and one of said plurality of switch actuating means, and

means for normally separating said first and second pluralities of contacts but permitting at least said common portion of said one of said first plurality of contacts to move toward said aligned portion of said one of said second plurality of contacts when a force is applied to said one of said switch actuating means to thereby effect a switching action by effecting a movement of said common portion of said one of said first plurality of contacts toward said one of said second plurality of contacts.

42. A keyboard switching device for effecting a switching action when a key is depressed comprising:

a plurality of key actuating means,

an electrically insulating planar substrate having a plurality of discrete metallic coatings on a surface thereof, at least some of said coatings having a group of unconnected, curved slots radiating outward from a common portion thereof, and

a plurality of electrically conductive contact members, at least one of said contact members having at least a portion thereof positioned in operative alignment with the common portion of at least one of said plurality of metallic coatings and with at least one of said switch actuating means,

said insulating substrate having an aperture therein adjacent to said central portions of said one of said plurality of coatings such that said common portion can be moved through at least a portion of said aperture toward said one of said plurality of contact members when a force is applied to said one of said switch actuating means to thereby effect a switching action.

43. The switching device of claim 42 wherein said slots radiate substantially continuously outward.

44. A keyboard switching device for effecting a switching action when a key is depressed comprising:

an electrically insulating substrate having a plurality of apertures therein,

a plurality of discrete metallic coatings supported by said substrate, at least one of said coatings having a forcibly movable portion axially aligned with one of said apertures, said movable portion defined by a group of unconnected, curved slots radiating outward from said movable portion,

a plurality of fixed contact members at least a portion of one of which is along said alignment axis, and

a plurality of switch actuating means,

one of said plurality of switch actuating means being positioned such that said forcibly movable portion of said one of said coatings can be forced by said one switch actuating means toward said portion of said one of said plurality of contact members to thereby effect a switching action.

45. The switching device of claim 44 wherein said slots are sections of a spiral.

46. The switching device of claim 44 wherein said slots have a smooth curve.

47. The switching device of claim 44 wherein said slots radiate substantially continuously outward.

48. A switching device comprising:

a switch actuating means,

a first electrically conductive contact member having a plurality of unconnected, curved slots radiating substantially continuously outwardly from a common portion thereof,

a second electrically conductive contact member having at least a portion thereof positioned in axial alignment with at least a portion of said common portion of said first contact member, and

means for normally separating said first and second contact members but permitting at least said common portion of said first contact member to move toward said aligned portion of said second contact member when a force is applied to said switch actuating means to thereby effect a switching action.

49. A switching device comprising:

a switch actuating means,

a first electrically conductive contact member having at least three curved, unconnected, outwardly radiating slots therein which define a common portion thereof, said at least three slots each having portions which are radially adjacent portions of the other of said at least three slots,

a second electrically conductive contact member having at least a portion thereof positioned in axial alignment with at least a portion of said common portion of said first contact member, and

means for normally separating said first and second contact members but permitting at least said common portion of said first contact member to move toward said aligned portion of said second contact member when a force is applied to said switch actuating means to thereby effect a switching action.

50. A switching device comprising:

a switch actuating means,

an electrically insulating planar substrate having a metallic coating over at least a portion of a surface thereof, said coating having a plurality of unconnected, curved slots radiating outward from a common portion of said coating, and

an electrically conductive contact member having at least a portion thereof positioned in axial alignment with at least a portion of said common portion of said coating,

said insulating substrate having an aperture therein adjacent to said common portion of said coating such that at least said common portion of said coating can be moved through at least a portion of said aperture toward said contact member when a force is applied to said switch actuating means to thereby effect a switching action.