Flat input keyboard for data processing machines or the like and process for producing the same

• US 5,748,114 A
• Filed: 04/24/1996
• Issued: 05/05/1998
• Est. Priority Date: 10/26/1993
• Status: Expired due to Fees

• Current Assignee: KO TA Koehn Tastatursysteme und Informationstechnologie GmbH
• Original Assignee: KO TA Koehn Tastatursysteme und Informationstechnologie GmbH
• Inventors: Koehn, Matthias-Reinhard
• Primary Examiner(s): Hofsass, Jeffery
• Assistant Examiner(s): Edwards, Jr., Timothy
• Application Number:
  US08/632,413
• Time in Patent Office: 741 Days
• Field of Search: 200/5 A, 200/86 R, 364/708.1, 364/709.01, 364/709.08, 364/709.11, 341/20, 341/22, 341/23, 361/749, 361/792, 361/793, 361/795, 174/254, 174/255
• US Class Current: 341/22
• CPC Class Codes: G06F 3/0202 Constructional details or processes of manufacture of the input device
• CPC Class Codes: G06F 3/0221 Arrangements for reducing keyboard size for transport or storage, e.g. foldable keyboards, keyboards with collapsible keys G06F3/0216 takes precedence; for keyboards integrated in a laptop computer G06F1/1666
• CPC Class Codes: G06F 3/033 Pointing devices displaced or positioned by the user , e.g. mice, trackballs, pens or joysticks; Accessories therefor digitisers characterised by the transducing means G06F3/041
• CPC Class Codes: G06F 3/0395 Mouse pads
• 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 2207/022 Plug
• CPC Class Codes: H01H 2207/032 Surface mounted component
• CPC Class Codes: H01H 2207/048 Inductive or infrared coupling
• CPC Class Codes: H01H 2209/03 elastomeric
• CPC Class Codes: H01H 2209/052 elastomeric
• CPC Class Codes: H01H 2209/074 elastomeric
• CPC Class Codes: H01H 2217/016 Pressure reduction membrane; Spreader layer
• CPC Class Codes: H01H 2223/052 reductible in size, e.g. for transportation

Abstract

A flat input keyboard for data processing machines or the like has the following successive layers, starting from the side facing away from the operation side: a supporting layer (10), an electric switching system (12, 16, 20) with electric contact spots that correspond to a keyboard pattern, a buffer layer (24) and a flexible elastic covering layer (26) provided on the operation side facing away from the electric switching system with a keyboard pattern (28). The supporting layer, the electric switching system, the buffer layer and the covering layer are interconnected at least along their circumference. The flat input keyboard is characterized in that the switching system is permanently flexible around roll axes as it is made up of segments (17) of at least one sheet, and is provided with a seamless casing (48) in a single piece since the supporting layer and the buffer layer are interconnected at their edges; the switching system is provided with flow openings (19) and the buffer layer and covering layer are interconnected over their whole surface. Also disclosed is a process for producing such a flat input keyboard.

Claims

1. Flat input keyboard for data processing machines or the like, which, starting on the side facing away from the operation side, has a supporting layer (10), an electric switching system (12, 16, 20) with electric contact spots corresponding to a keyboard pattern and a flexible elastic covering layer (26) having a keyboard pattern and provided on the operation side facing away from the electric switching system wherein the supporting layer (10), the multi layer electric switching system (12, 16, 20) and the covering layer (26) are interconnected at least along their circumference, wherein the electric switching system (12, 16, 20) is provided with desired bending lines, which are formed through segmentation (17) of individual or several sheet layers of the electric switching system.

2. Flat input keyboard according to claim 1 characterized by, that the supporting layer (10), the electric switching system (12, 16, 20), the buffer layer (24) and the covering layer (26) are formed in an essentially elongated manner;

and that the supporting layer (10) has at least on one side an essentially rigid first edge web (30,

     32) that runs parallel to the roll axis.

3. Flat input keyboard according to claim 1, characterized by, that the electric switching system (12, 16, 20) has a short-stroke keyboard with short-stroke keys rigidly affixed to a flexible board or the like.

4. Flat input keyboard according to claim 1, wherein the electric switching system (12, 16, 20) in a mold has flow openings for receiving plastic material therethrough in such a way to form in the in the final condition a single-piece seamless casing (48) for the electric switching system.

5. Flat input keyboard according to claim 4, characterized by a number of connecting webs passing through flow openings (19) in the electric switching system (12, 16, 20) so that the supporting layer (10), the buffer layer (24) and the covering layer (26) are joined to each other, thereby fixing the relative positions of the function elements of the electric switching system.

6. The method according to claim 5 further including the step of applying the keyboard pattern to the covering layer after the casting, injection molding or steaming and curing process as any necessary mold-removal has been completed.

7. Flat input keyboard according to claim 1, . . . unchanged first contact sheet (12) to which is applied at least zonally a first contact layer (14), next a spacing facility (16) provided with openings (18) that correspondingly match the keyboard pattern (28), and on the side facing towards the spacing facility (16) a second contact sheet (20) to which is applied at least zonally an electroconductive second contact layer (22).

8. Flat input keyboard according to claim 7, characterized by, that between the second contact sheet (20) and the covering layer (26) there is arranged an elastically yielding buffer layer.

9. Flat input keyboard according to either of claims 7 and 8, characterized by, that the spacing facility is at least partially comprised of the discrete spacing elements (16) surrounding the contact points corresponding to the keyboard pattern (28) and of the air ducts connecting these.

10. Flat input keyboard according to claim 9, characterized by, that the spacing elements (16) are essentially formed as a ring-shaped area.

11. Flat input keyboard according to either of claims 9 or 10, characterized by, that one of the contact sheets (12, 20) is at least zonally comprised of the discrete contact zones corresponding to the spacing elements (16).

12. Flat input keyboard according to claim 11, characterized by, that the contact zones are essentially formed as a ring-shaped area.

13. Flat input keyboard according to one of claims 9 through 10, characterized by, that one of the contact sheets (12, 20) carries all of the discrete electric conductors.

14. Flat input keyboard according to claim 13, characterized by, that at the contact spots corresponding to the keyboard pattern (28), the conductors reach into each other in a comb-like manner.

15. Flat input keyboard according to claim 14 characterized by, that the contact zones on the side facing towards the spacing elements have an essentially complete electroconductive coating and that at least one contact sheet (12, 20) carries the discrete electric conductors.

16. Flat input keyboard according to one of the preceding claims, characterized by, that the electric contact spots of the contact sheets (12, 20) are arranged in rows parallel to the roll axis.

17. Flat input keyboard according to one of the preceding claims, characterized by, that at least one of the sheets of the electric switching system (12, 16, 20) comprises a number of sheet segments (17) running parallel to the roll axis.

18. Flat input keyboard according to one of the preceding claims, characterized by, that at least one of the outer lying sheets of the electric switching system (12, 16, 20) in combination with the spacing facility (16) comprises a number of sheet segments (17) running parallel to the roll axis.

19. Flat input keyboard according to one of the preceding claims, characterized by, that all the sheets of the electric switching system (12, 16, 20) in combination comprise a number of sheet segments (17) running parallel to the roll axis.

20. Flat input keyboard according to claim 1 characterized by, that the supporting layer (10) has at least on one side a second edge web that is essentially perpendicular to the roll axis.

21. Flat input keyboard according to claim 2 or 20, characterized by, that at least the first edge webs (30, 32) are detachably connected to the supporting layer (10), the electric switching system (12, 16, 20), the buffer layer (24) the covering layer (26).

22. Flat input keyboard according to claim 2 or 20, characterized by, that at least the first edge webs (30, 32) are a fixed part of the casing (48).

23. Flat input keyboard according to claim 20 or 21, characterized by, that at least the second webs (30, 32) are flexibly formed around the roll axis.

24. Flat input keyboard according to one of claims 2 through 23, characterized by, that an illumination facility (36) which illuminates the keyboard pattern from the side is integrated in at least one of the edge webs (30, 32).

25. Flat input keyboard according to one of claims 2 through 23, characterized by, that there is a connector cable firmly integrated in one of the edge webs.

26. Flat input keyboard according to one of the preceding claims, characterized by a detachable plug connection (34) for connecting to a data processing unit or the like.

27. Flat input keyboard according to one of claims 2 through 26, characterized by, that the plug connection (34) is integrated in one of the edge webs (30, 32).

28. Flat input keyboard according to one of the preceding claims, characterized by, that a part of the keyboard pattern (28) of the covering layer (26) is formed as the operating area for a computer mouse (46).

29. Flat input keyboard according to one of the preceding claims, characterized by, that a control unit (38) is integrated in one of the edge webs (30, 32).

30. Flat input keyboard according to claim 29, characterized by, that the control unit (38) comprises an SMD module.

31. Flat input keyboard according to one of the preceding claims, characterized by, that there are optical display facilities integrated in a part of the keyboard pattern (28) the covering layer (26) or in the edge webs (30, 32).

32. Flat input keyboard according to one of the preceding claims, characterized by, that there are acoustic display facilities integrated in a part of the keyboard pattern (28) the covering layer (26) or in the edge webs (30, 32).

33. Flat input keyboard according to one of the preceding claims, characterized by, that there are transmitter and receiver units for digital signals integrated in a part of the keyboard pattern (28) the covering layer (26), the buffer layer (24) or in the edge webs (30, 32).

34. Flat input keyboard according to one of the preceding claims, characterized by, that there are power sources integrated in a part of the keyboard pattern (28) the covering layer (26), the buffer layer (24), the circumferential edge web or in the edge webs (30, 32).

35. Flat input keyboard according to one of the preceding claims, characterized by an accessory base formed as a support plate (40) and/or baseplate (44) for incorporating the supporting layer (10), the electric switching system (12, 16, 20), and if need be the edge webs (30, 32).

36. Flat input keyboard according to claim 35, characterized by, that the baseplate (44) has on its upper side a recess (42) with a level support area for receiving in a form-closed manner the supporting layer (10) and/or the support plate (40) and if need be the edge webs (30, 32).

37. Flat input keyboard according to one of the preceding claims, characterized by, that the electric switching system (12, 16, 20) has a sensor keyboard that is essentially free of mechanically movable function elements.

38. Flat input keyboard according to one of the preceding claims, characterized by extended air chambers corresponding to the keyboard pattern (28) for application under extreme pressure conditions or the like.

45. A flat input keyboard manufactured according to the method of claim 38 comprising:

starting on the side facing away from the operation side, a supporting layer, an electric switching system with electric contact spots corresponding to a keyboard pattern and a flexible elastic covering layer having a keyboard pattern and provided on the operation side facing away from the electric switching system, wherein the supporting layer, the electric switching system and the covering layer are interconnected at least along their circumference , wherein the electric switching system is provided with desired bending lines, which are formed through segmentation of individual or several sheet layers.

39. A method for manufacturing a flat input keyboard comprising the steps off;

casting an electric switching system in plastic material, forming the supporting layer the buffer layer, the covering layer and a continuous circumferential edge web of the casing, and joining the supporting layer, buffer layer, and covering layer to a single piece by the continuous circumferential edge web.

40. The method according to claim 39 wherein the step of casting includes the step of injection molding in a die mold closed on all sides.

41. The method according to claim 39, wherein the step of casting includes using a thermoplastic or thermosetting material.

43. The method according to claim 39 further including the step of:

using a polyurethane for the plastic material.

44. The method according to claim 39 further including the step of using a silicon for the plastic material.

46. The method according to claim 39, further comprising the step of elastically curing the plastic material.

47. The method according to claim 40, wherein the step of casting includes using a liquid castable and then curable elastomeric plastic material.

48. The method according to claim 47, further including the steps of using a casting mold, the inner dimensions at base level exceed the outer dimensions of the electric switching system on all sides by the width of the circumferential web to be formed, pouring into the casting mold first the covering layer and the buffer layer, allowing the first layer of the plastic material to at least partially cure;

leaving the at least partially cured covering layer and buffer layer in the mold;

introducing the electric switching system into the mold and placing said system on the supporting layer, providing a border the width of which corresponds to the circumferential web to be formed;

then adding further liquid castable plastic material wherein the circumferential edge strip is filled up and the electric switching system is covered to a height corresponding to the thickness of the supporting layer; and

then fully curing the entire plastic material and then removing the one-piece tightly enclosed flat input keyboard from the mold.

49. The method according to claim 39 further including the steps of making the parallel sections of the circumferential edge web parallel to the roll axis being made essentially rigid, and making the sections of the circumferential edge web that are perpendicular to the bending axis or roll axis essentially flexible.

50. The method according to claim 49, further including the step of making the rigid and flexible sections of the circumferential end web of the casing in different thicknesses.

51. The method according to claim 49 further including the step of using different materials for the rigid and flexible sections of the circumferential end web of the casing.

42. The method according to 39 claim further including the steps of using an electric switching system that has a multiplicity of openings both on the side where the supporting layer is to be provided as well as on the side where the covering layer and the buffer layer are to be provided;

and casting the casting material into these openings, curing the material for obtaining an elastic, single-piece, spatial matrix consisting of the supporting layer, the covering layer, the buffer layer, the circumferential edge web, the casing and joining webs for penetrating the electric switching system and fixing its function elements in spatially defined relative positions, joining the supporting layer, the covering layer, the buffer layer and the circumferential edge web through the openings in the electric switching system.