Display board type switching device

• US 4,317,012 A
• Filed: 04/17/1980
• Issued: 02/23/1982
• Est. Priority Date: 04/26/1979
• Status: Expired due to Term

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Nissan Motor Co., Ltd.
• Inventors: Itoh, Toshiyuki
• Primary Examiner(s): Truhe, J. V.
• Assistant Examiner(s): Ginsburg, Morris
• Application Number:
  US06/141,192
• Time in Patent Office: 677 Days
• Field of Search: 200/5 A, 200/5 R, 200/159 R, 200/159 A, 200/262, 200/264, 200/267, 200/83 N, 338/99, 338/100, 338/114, 338/118, 340/365 R, 264/277, 264/236, 29/622
• US Class Current: 200/5.00A
• CPC Class Codes: B29C 45/02 Transfer moulding, i.e. transferring the required volume of moulding material by a plunger from a "shot" cavity into a mould cavity
• CPC Class Codes: B29C 70/68 by incorporating or moulding on preformed parts, e.g. inserts or layers , e.g. foam blocks mould constructions therefor B29C33/12; joining preformed parts by moulding B29C65/70
• CPC Class Codes: B29K 2021/00 Use of unspecified rubbers as moulding material
• CPC Class Codes: B29K 2105/24 crosslinked or vulcanised
• CPC Class Codes: B29K 2995/0005 Conductive
• CPC Class Codes: B29K 2995/0007 Insulating
• CPC Class Codes: B29L 2031/46 Knobs or handles , push-buttons, grips buttons for haberdashery B29L2019/00, press-buttons as fastening element B29L2031/7282
• 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 2201/036 Variable resistance
• CPC Class Codes: H01H 2205/022 Conductive rubber
• CPC Class Codes: H01H 2205/024 Means to facilitate positioning
• CPC Class Codes: H01H 2209/006 Force isolators
• CPC Class Codes: H01H 2227/012 Conductive rubber
• CPC Class Codes: H01H 2229/044 Injection moulding
• CPC Class Codes: H01H 2229/058 Curing or vulcanising of rubbers
• CPC Class Codes: H01H 2231/026 Car
• CPC Class Codes: H01H 2239/03 Avoiding erroneous switching
• CPC Class Codes: H03K 17/9643 using a plurality of detectors, e.g. keyboard

Abstract

A display board type switching device used for a vehicle or the like, in which pressure sensitive conducting rubber member (7) is integrally molded in a sheet (6) to form a substantially flat plate to rigidly fix the position of the pressure sensitive rubber member. A method for forming such sheet is also described.

Claims

1. A switching device, comprising;

a flexible display board having a number of switching positions,

a sheet member in parallel and slightly spaced relationship with said flexible display board,

a number of pressure sensitive conducting rubber members integrally molded with said sheet member and disposed in corresponding positions to said switching positions respectively,

a pair of electrodes at positions corresponding to and connectable through each of said rubber members,

a hard base plate having cutout holes at positions corresponding to said respective switching positions disposed between said flexible display board and said sheet member, and

conducting bodies at said switching positions respectively contactable with the upper side of said conducting rubber members.

2. A switching device according to claim 1, wherein said pair of electrodes are disposed on the lower side of said conducting rubber members and opposite said conducting bodies.

3. A switching device as claimed in claim 1 wherein one of said pair of electrodes is disposed at the corresponding one of said switching positions and on the upper side of said conducting rubber members, and the other of said pair of electrodes is disposed on the opposite side of said corresponding rubber member and electrode.

4. A switching device as claimed in claim 1, wherein said sheet member is made of silicon rubber.

5. A switching device as claimed in claim 1, wherein said sheet member is made of plastics.

6. A method for manufacturing a sheet member for a pressure sensitive display board switching device and having a number of pressure sensitive conducting rubber members integrally molded with said sheet member, comprising the steps of;

arranging the number of pressure sensitive conducting rubber members at corresponding switching positions in a lower mold,

extruding gel-like insulative rubber compound from an upper mold by an extruding mold, and

vulcanizing the insulative rubber compound in the lower mold and thereby forming a flat rubber sheet having substantially the same height as that of the pressure sensitive conducting rubber members with said conducting rubber members being embedded in the insulative sheet.

7. A method as claimed in claim 6, wherein the lower mold is provided with depressions for fixing the pressure sensitive rubber members at the corresponding switching positions.

8. A method as claimed in claim 6, wherein the pressure sensitive rubber members are placed in fixed position in the lower mold by using an insulative sheet provided with cut portions correspondingto the respective switching positions and each cut is slightly larger than the rubber member, and thereafter the insulative rubber compound is extruded into the mold to bind said pressure sensitive members to said insulative sheet.