Key panel including key pad and strip of printed wiring material having various aspect ratios and method of making

• US 6,359,242 B1
• Filed: 07/07/2000
• Issued: 03/19/2002
• Est. Priority Date: 02/25/2000
• Status: Expired due to Fees

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Hewlett-Packard Company (HP Inc.)
• Inventors: Maple, Larry E.
• Primary Examiner(s): Scott, J. R.
• Application Number:
  US09/612,550
• Time in Patent Office: 620 Days
• Field of Search: 200/5.A, 200/5.R, 200/86.R, 200/512-517, 200/292, 200/293-296, 174/250-268, 361/679-681, 361/748, 361/749, 341/22-35
• 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 2229/022 Modular assembly
• CPC Class Codes: H01H 2229/034 Positioning of layers
• CPC Class Codes: H01H 2229/038 Folding of flexible printed circuit

Abstract

A key panel comprises a key pad having a number of key sites provided thereon that define an aspect ratio for the key pad. A strip of printed wiring material is positioned adjacent the key pad. A number of switch contact sites provided on the strip of printed wiring material define an aspect ratio for the strip of printed wiring material that is greater than the aspect ratio of the key pad. The strip of printed wiring material is provided with at least one fold therein so that each of the number of switch contact sites provided on the strip of printed wiring material is generally aligned with a corresponding one of the number of key sites provided on the key pad.

Claims

1. A key panel, comprising:

a key pad having a number of key sites provided thereon that define an aspect ratio for said key pad; and

a strip of printed wiring material positioned adjacent said key pad, said strip of printed wiring material having a number of switch contact sites provided thereon that define an aspect ratio for said strip of printed wiring material that is greater than the aspect ratio of said key pad, said strip of printed wiring material having at least one fold formed therein so that each of the number of switch contact sites provided on said strip of printed wiring material is generally aligned with a corresponding one of the number of key sites provided on said key pad.

2. The key panel of claim 1, further comprising a subpanel, said strip of printed wiring material being positioned in contact with said subpanel, said subpanel providing support for said strip of printed wiring material.

3. The key panel of claim 2, wherein said strip of printed wiring material is affixed to said subpanel.

4. The key panel of claim 1, wherein said strip of printed wiring material comprises:

a substrate; and

an electrical conductor adhered to said substrate, said electrical conductor forming the number of switch contact sites.

5. The key panel of claim 4, wherein each of the number of switch contact sites formed by said electrical conductor comprises a first electrically conductive trace and a second electrically conductive trace, said first and second electrically conductive traces being positioned in spaced-apart relationship on said substrate, and wherein each of the number of key sites provided on said key pad comprises an electrically conductive portion, the electrically conductive portion on each of the number of key sites contacting at least portions of both said first and second electrically conductive traces on said substrate when each of the number of key sites is depressed.

6. The key panel of claim 5, further comprising a bezel defining a number of openings therein aligned with the number of key sites provided on said key pad, said bezel being positioned over said key pad so that the number of key sites may be accessed by an operator through the number of openings provided in said bezel.

7. The key panel of claim 6, further comprising at least one alignment pin provided on said bezel, and wherein said key pad defines at least one through hole therein sized to receive said at least one alignment pin on said bezel and wherein said strip of printed wiring material defines at least one through hole therein sized to receive said at least one alignment pin on said bezel, said at least one alignment pin of said bezel aligning the key sites provided on said key pad with corresponding ones of the switch contact sites provided on said strip of printed wiring material.

8. The key panel of claim 1, wherein said strip of printed wiring material comprises a front side and a back side, each of said switch contact sites provided in said strip of printed wiring material being actuated from the front side of said strip of printed wiring material.

9. The key panel of claim 1, wherein said strip of printed wiring material comprises a front side and a back side, wherein at least one of the number of switch contact sites is provided on the front side of said strip of printed wiring material and wherein at least one of the number of switch contact sites is provided on the back side of said strip of printed wiring material.

10. The key panel of claim 9, wherein said key pad is positioned adjacent the front side of said strip of printed wiring material and further comprising a second key pad positioned adjacent the back side of said strip of printed wiring material.

11. The key panel of claim 1, wherein the number of switch contact sites on said strip of printed wiring material is at least equal to the number of key sites on said key pad.

12. The key panel of claim 1, wherein said key pad is fabricated from an elastomer.

13. The key panel of claim 1, wherein said key pad comprises a unitary member.

14. The key panel of claim 1, wherein said key pad comprises a silicone rubber material.

15. A key panel, comprising:

a key pad having a number of key sites arranged in a pattern so as to define an aspect ratio for said key pad; and

a strip of printed wiring material having a number of switch contact sites provided thereon so as to define an aspect ratio for said strip of printed wiring material that is greater than the aspect ratio of said key pad, said strip of printed wiring material having at least one fold formed therein so as to arrange in the pattern the number of switch contact sites provided on said strip of printed wiring material.

16. The key panel of claim 15, wherein said strip of printed wiring material comprises:

a substrate; and

an electrical conductor adhered to said substrate, said electrical conductor forming the number of switch contact sites.

17. The key panel of claim 16, wherein each of the number of switch contact sites formed by said electrical conductor comprises a first electrically conductive trace and a second electrically conductive trace, said first and second electrically conductive traces being positioned in spaced-apart relationship on said substrate, and wherein each of the number of key sites provided on said key pad comprises an electrically conductive portion, the electrically conductive portion on each of the number of key sites contacting at least portions of both said first and second electrically conductive traces on said substrate when each of the number of key sites is depressed.

18. A key panel, comprising:

key pad means for defining a number of key sites that define an aspect ratio for said key pad; and

printed wiring material means positioned adjacent said key pad means for providing a number of switch contact sites thereon that define an aspect ratio for said printed wiring material means that is greater than the aspect ratio of said key pad means and for aligning the switch contact sites with corresponding ones of the number of key sites defined by said key pad means.

19. A method for fabricating a key panel, comprising:

selecting a key pad having a number of key sites provided thereon that define an aspect ratio for said key pad;

selecting a strip of printed wiring material having a number of switch contact sites provided thereon that define an aspect ratio for said strip of printed wiring material that is greater than the aspect ratio of said key pad; and

folding said strip of printed wiring material so as to align ones of the number of switch contact sites with corresponding ones of the number of key sites.

20. A method for fabricating a key panel, comprising:

selecting a key pad having a number of key sites provided thereon that define an aspect ratio for said key pad;

fabricating a strip of printed wiring material having a number of switch contact sites provided thereon that define an aspect ratio for said strip of printed wiring material that is greater than the aspect ratio of said key pad; and

folding said strip of printed wiring material so as to align ones of the number of switch contact sites with corresponding ones of the number of key sites.