Keyboard switch

• US 4,485,279 A
• Filed: 09/30/1982
• Issued: 11/27/1984
• Est. Priority Date: 02/16/1982
• Status: Expired due to Fees

• Current Assignee: ALPS Electric Company Limited (Alps Alpine Co., Ltd.)
• Original Assignee: ALPS Electric Company Limited (Alps Alpine Co., Ltd.)
• Inventors: Nakamura, Moritoshi
• Primary Examiner(s): Scott, J. R.
• Application Number:
  US06/431,386
• Time in Patent Office: 789 Days
• Field of Search: 200/5 A, 200/8 LR, 200/159 B, 200/306
• 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 2213/008 Flaps cut out forming valves

Abstract

A keyboard switch includes upper and lower substrates spaced from each other by a spacer having a plurality of spaces in which upper and lower contacts respectively on the upper and lower substrates are placed, respectively. An insulating sheet is sandwiched between the lower substrate and a base plate and has a plurality of slits aligned respectively in vent holes in the base plate and the lower substrate for preventing substantial passage therethrough of dirt or dust while allowing air to flow therethrough.

Claims

1. A keyboard switch comprising:

(a) a base plate having a plurality of first vent holes;

(b) an insulating sheet mounted on said base plate and a plurality of slits located respectively in alignment with said first vent holes for preventing substantial passage therethrough of dirt or dust while permitting air to flow therethrough;

(c) a first substrate mounted on said insulating sheet and having a plurality of second vent holes respectively in alignment with said first vent holes and said slits, said first substrate supporting a plurality of first contacts;

(d) an insulating spacer mounted on said first substrate and having a plurality of spaces in which said first contacts are positioned, respectively, said first vent holes, said slits and said second vent holes communicating with said spaces; and

(e) a second substrate mounted on said insulating spacer and having a plurality of second contacts placed in said spaces respectively in alignment with said first contacts.

2. A keyboard switch according to claim 1, wherein said first contacts have recessed edges, said second vent holes being located adjacent to said recessed edges, respectively.