Internally-illuminable push-button switch unit

• US 5,573,107 A
• Filed: 08/08/1995
• Issued: 11/12/1996
• Est. Priority Date: 08/10/1994
• Status: Expired due to Term

• Current Assignee: Shin-Etsu Polymer Company Limited (Shin-Etsu Chemical Company Limited)
• Original Assignee: Shin-Etsu Polymer Company Limited (Shin-Etsu Chemical Company Limited)
• Inventors: Nakafuji, Noboru, Motoki, Toshihiro, Kiyosawa, Mikio, Nakano, Sadao
• Primary Examiner(s): Walczak, David J.
• Application Number:
  US08/512,554
• Time in Patent Office: 462 Days
• Field of Search: 200/314, 200/313, 200/311, 200/310, 200/512, 200/514, 200/517, 200/308
• US Class Current: 200/314
• CPC Class Codes: C09K 11/02 Use of particular materials as binders, particle coatings or suspension media therefor
• 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 13/785 characterised by the material of the contacts, e.g. conductive polymers
• CPC Class Codes: H01H 2201/032 Conductive polymer; Rubber
• CPC Class Codes: H01H 2205/006 mounted on spacer
• CPC Class Codes: H01H 2209/002 Materials
• CPC Class Codes: H01H 2209/038 transparent
• CPC Class Codes: H01H 2209/06 transparent
• CPC Class Codes: H01H 2209/082 transparent
• CPC Class Codes: H01H 2215/01 Part of spacer
• CPC Class Codes: H01H 2215/036 Metallic disc
• CPC Class Codes: H01H 2219/014 LED
• CPC Class Codes: H01H 2219/018 Electroluminescent panel
• CPC Class Codes: H01H 2219/034 Coloured areas
• CPC Class Codes: H01H 2221/05 Force concentrator; Actuating dimple
• CPC Class Codes: H01H 2221/07 transparent
• CPC Class Codes: H01H 2229/046 Multi-colour or double shot injection moulding
• CPC Class Codes: H05B 33/00 Electroluminescent light sources
• CPC Class Codes: H05B 33/10 Apparatus or processes specially adapted to the manufacture of electroluminescent light sources
• CPC Class Codes: H05B 33/12 : Light sources with substantially two-dimensional radiating surfaces
• CPC Class Codes: H05B 33/20 : characterised by the chemical or physical composition or the arrangement of the material in which the electroluminescent material is embedded
• CPC Class Codes: H05B 33/22 : characterised by the chemical or physical composition or the arrangement of auxiliary dielectric or reflective layers
• CPC Class Codes: H05B 33/26 : characterised by the composition or arrangement of the conductive material used as an electrode
• CPC Class Codes: H05B 33/28 : of translucent electrodes

Abstract

An improved internally-illuminable push-button switch unit is proposed, which is an assembly comprising:

(a) an upper sheet member integrally consisting of a first elastic sheet having such a light-transmissivity as to ensure image-visibility therethrough and a key-top part made from a light-transmitting synthetic resin having a Shore D hardness of at least 40 and protruded on the upper surface of the first elastic sheet;

(b) a lower sheet member integrally consisting of a second light-transmitting elastic sheet and a click-plate presser made from a light-transmitting material and protruded on the lower surface of the second elastic sheet, the lower sheet member being positioned below the upper sheet member;

(c) a light-conducting plate positioned below the lower sheet member;

(d) a click plate positioned below the lower sheet member;

(e) a circuit board positioned below the lower sheet member; and

(f) a light source positioned below the lower sheet member and above the circuit board,

at least either one of the first and the second elastic sheets being provided on at least one of the surfaces with a colored layer.

Claims

1. An internally-illuminable push-button switch unit which comprises, as an assembly:

(a) an upper sheet member integrally consisting of a first elastic sheet having such a light-transmissivity as to ensure image-visibility therethrough and a key-top part made from a light-transmitting synthetic resin having a Shore D hardness of at least 40 and protruded on an upper surface of the first elastic sheet;

(b) a lower sheet member integrally consisting of a second-light transmitting elastic sheet having an upper and a lower surface, and a click-plate presser made from a light-transmitting material and protruded on the lower surface of the second elastic sheet, the lower sheet member being positioned below the upper sheet member;

(c) a light-conducting plate having an upper surface adjacent the lower surface of the second light-transmitting elastic sheet and a lower surface positioned below the second light-transmitting elastic sheet;

(d) a click plate having an upper surface adjacent the lower surface of the light conducting plate and a lower surface positioned below the lower sheet member;

(e) a circuit board having an upper surface adjacent the lower surface of the click plate; and

(f) a light source positioned below the lower sheet member and above the circuit board, at least either one of the first and second elastic sheets being provided on at least one of the surfaces with a colored layer.

2. The internally-illuminable push-button switch unit as claimed in claim 1 in which at least either one of the first and the second elastic sheets is provided with a light-transmitting colored layer and a light-shielding colored layer having an opening through which the light-transmitting colored layer under illumination by the light source is seeable through the key-top part.

3. The internally-illuminable push-button switch unit as claimed in claim 1 in which the click plate has a movable contact point on the lower surface thereof and the circuit board has a pair of fixed contact points to face the movable contact point so as to be brought into contact with the movable contact point when the key-top part is pushed down.