PUSHBUTTON DIAPHRAGM SWITCH WITH IMPROVED DIMPLE ACTUATOR AND/OR CAPACITANCE-TYPE SWITCH CONTACT STRUCTURE

• US 3,643,041 A
• Filed: 12/30/1970
• Issued: 02/15/1972
• Est. Priority Date: 12/30/1970
• Status: Expired due to Term

• Current Assignee: Charles A. Jackson
• Original Assignee: Charles A. Jackson
• Inventors: Jackson, Charles A.
• Primary Examiner(s): Scott, J. R.
• Application Number:
  US05/102,803
• Time in Patent Office: 412 Days
• Field of Search: 200/1R,5A,DIG.1,159B
• 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 2201/026 non precious
• CPC Class Codes: H01H 2203/004 Rivet
• CPC Class Codes: H01H 2203/032 Metal foil
• CPC Class Codes: H01H 2209/07 metallic
• CPC Class Codes: H01H 2215/008 Part of substrate or membrane
• CPC Class Codes: H01H 2223/036 forming chamfered apertures for keys
• CPC Class Codes: H01H 2227/004 Membrane
• CPC Class Codes: H01H 2227/022 Collapsable dome
• CPC Class Codes: H01H 2239/006 Containing a capacitive switch or usable as such

Abstract

A faceplate is provided with a plurality of openings therein, each representing a digit to be used in a keyboard; a metal switch plate is positioned immediately beneath the faceplate and includes a plurality of dome-shaped resilient deformable dimples forming keys therein, each registering with and extending into a different one of said openings. An insulating plate, with holes therein registering with the dimples, separates the switch plate from a contact board that includes a plurality of contact buttons, each registering with one of the holes in the insulating plate. The dimples may be depressed by the fingertip of an operator to '"'"''"'"''"'"''"'"'snap'"'"''"'"''"'"''"'"' into contact with a corresponding contact button and will '"'"''"'"''"'"''"'"'snap'"'"''"'"''"'"''"'"' back to their original position when fingertip pressure is released.

Claims

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

a switchplate, having a plurality of resilient deformable dimples forming keys therein, each having a convex surface;

a contact board, positioned adjacent and parallel to said switchplate, having a plurality of electrical contacts, each registering with a different one of said dimples;

insulating means electrically insulating said contact board from said switchplate;

each of said dimples, when depressed by an operator'"'"''"'"'s fingertip depressing the convex surface thereof, contacting a corresponding one of said contacts, and when released snapping back to its original position.

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

a faceplate including a plurality of openings thereon;

a switchplate, positioned parallel to said faceplate, having a plurality of resilient deformable dimples forming keys therein, each having a convex surface registering with and extending into a different one of said openings;

a contact board, positioned adjacent and parallel to said switchplate, having a plurality of electrical contacts, each registering with a different one of said dimples;

insulating means electrically insulating said contact board from said switchplate;

each of said dimples, when depressed by an operator'"'"''"'"'s fingertip depressing the convex surface thereof, contacting a corresponding one of said contacts, and when released snapping back to its original position.

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

a faceplate, including a plurality of openings therein;

a metal switchplate, positioned parallel to said faceplate, having a plurality of dome-shaped resilient deformable dimples forming keys therein, each having a convex surface registering with and extending into a different one of said openings;

an insulating plate, positioned adjacent to and parallel to said switchplate, having a plurality of holes, each registering with a different one of said dimples;

a contact board, positioned adjacent to and parallel to said insulating plate, having a plurality of electrical contacts, each registering with a different one of said holes;

each of said dimples, when depressed by an operator'"'"''"'"'s fingertip depressing the convex surface thereof, extending through one of said holes and contacting a corresponding one of said contacts, and when released snapping back to its original position.

4. The combination set forth in claim 2, wherein each of said keys, when depressed, transmits a mechanical sensory feedback signal in the form of a snap sensation through the fingertip of the operator to indicate that the key has been properly depressed.

5. The combination set forth in claim 2, wherein said switchplate is a continuous flat metal sheet having a plurality of dome-shaped resilient deformable dimples therein.

6. The combination set forth in claim 2, wherein said switchplate comprises a continuous sheet of plastic material having a metallized surface thereon, said metallized surface including the concave surfaces of said dimples.

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

a faceplate, including a plurality of openings therein;

a switchplate positioned parallel to said faceplate, having a plurality of dome-shaped resilient deformable dimples forming keys therein, each having a convex surface registering with and extending into a different one of said openings;

an insulating plate positioned adjacent and parallel to said switchplate;

a contact board positioned adjacent and parallel to said insulating plate, having a plurality of electrical contacts, each registering with a different one of said dimples, a predetermined capacitance existing between each of said dimples and the corresponding electrical contact;

each of said dimples, when depressed by an operator'"'"''"'"'s fingertip depressing the convex surface thereof, contacting said insulating plate and changing the capacitance between the dimple and corresponding electrical contact.

8. The combination set forth in claim 7, wherein each of said keys, when depressed, transmit a mechanical sensory feedback signal in the form of a snap sensation through the fingertip of the operator to indicate that the key has been properly depressed.

9. The combination set forth in claim 7, wherein said switchplate comprises a continuous flat metal sheet having a plurality of dome-shapEd resilient deformable dimples therein.

10. The combination set forth in claim 7, wherein said switchplate comprises a continuous sheet of plastic material having a metallized surface thereon, said metallized surface including the concave surfaces of said dimples.