Waterproof keyboard

• US 20050224326A1
• Filed: 04/06/2005
• Published: 10/13/2005
• Est. Priority Date: 04/07/2004
• Status: Active Grant

• Current Assignee: Keytec BV
• Original Assignee: Keytec BV
• Inventors: Oikawa, Hiroaki
• Granted Patent: US 7,012,206 B2
• Time in Patent Office: Days
• US Class Current: 200/302.100
• CPC Class Codes: H01H 13/063 Casings hermetically closed by a diaphragm through which passes an actuating member vacuum switches H01H33/66
• CPC Class Codes: H01H 2223/002 sealed
• CPC Class Codes: H01H 2223/003 Membrane embracing all keys
• CPC Class Codes: H01H 2231/044 Under water
• CPC Class Codes: H01H 2233/07 Cap or button on actuator part
• CPC Class Codes: H01H 9/041 Casings hermetically closed by a diaphragm through which passes an actuating member vacuum switches H01H33/66

Abstract

A waterproof keyboard includes a generally flat key panel supporting keytops thereon. Membranes support thereon key contacts and connecting circuits for the contacts, and are supported by a generally flat support base, corresponding in shape to the key panel. Between the membranes and the key panel, a waterproof layer is supported by the support base for sealing the membranes in cooperation with the base. The waterproof layer, made of a sheet of flexible synthetic resin, is pressed with an elongate elastic member against the edge portion of the support base. The key panel is fixed to the support base to cause the waterproof layer and support base to seal the membranes, which will surely be protected from dust and moisture.

Claims

1. A keyboard comprising:

a first frame having a generally rectangular planer shape for supporting a plurality of keytops;

a circuit support supporting a corresponding plurality of key contacts and connecting circuits for said corresponding plurality of key contacts;

a second frame having a planer shape corresponding to the planer shape of said first frame and constituting a base for supporting said circuit support;

a waterproof layer intervening between said circuit support and said first frame, when supported by said second frame, to seal said circuit support in cooperation with said second frame;

an elongate elastic member pressing said waterproof layer against an edge portion of said second frame; and

a fastener for fastening said first frame and said second frame to each other;

said waterproof layer being made of a flexible synthetic resin,

said fastener pressing said first frame and said second frame against each other with said elongate elastic member intervening between said first frame and said second frame to thereby cause said waterproof layer and said second frame to seal said circuit support, whereby said circuit support is protected from dust and moisture.

2. The keyboard in accordance with claim 1, wherein said waterproof layer is formed of an elastic synthetic resin, and has a dome-click mechanism molded integrally with said waterproof layer for closing said key contacts.

3. The keyboard in accordance with claim 1, further comprising a corresponding plurality of dome members formed of an elastic synthetic resin for respectively engaging with said plurality of keytops, said waterproof layer comprising a thin, extendible sheet of synthetic resin, said plurality of dome members being made of an elastic synthetic resin and positioned between said waterproof layer and said first frame.

4. The keyboard in accordance with claim 1, wherein said waterproof layer comprises a thin, extendible sheet of synthetic resin, and is positioned at substantially a same level as switch devices respectively including said plurality of key contacts in a direction perpendicular to a general plane formed by said second frame.

5. The keyboard in accordance with claim 3, wherein said circuit support comprises a membrane on which said plurality of key contacts and said connecting circuits are arranged, said waterproof layer being positioned at substantially a same level as said circuit support in a direction perpendicular to a general plane formed by said second frame.

6. A keyboard comprising:

a keytop support having a generally rectangular planer shape for supporting a plurality of keytops;

a circuit support supporting a corresponding plurality of key contacts and connecting circuits for said corresponding plurality of key contacts;

a frame having a contour corresponding to the planer shape for supporting said circuit support;

a waterproof layer intervening between said circuit support, when supported by said frame, and said keytop support for sealing said circuit support in cooperation with said frame;

an elongate elastic member fitted in an edge portion of said frame to press said waterproof layer against said edge portion;

a bottom plate positioned at a side opposite to said keytop support with respect to said circuit support, when supported by said frame, for closing an opening of said frame; and

a fixing device for sealing a clearance between said bottom plate and said frame and fixing said bottom plate to said frame;

said waterproof layer being made of a flexible synthetic resin, said elongate elastic member sealing said waterproof layer to an edge portion of said frame to thereby protect said circuit support from dust and moisture.

7. The keyboard in accordance with claim 6, wherein said fixing device includes a groove formed in said frame for receiving an edge of said bottom plate.

8. The keyboard in accordance with claim 6, wherein said fixing device includes a pressing member engaged with said frame to thereby support an edge of said bottom plate.