Patent ID: 6664901
Filing Date: 2003-12-16
Classification: H01H

Abstract:
A keyboard input device comprising:a flexible film substrate; a conducting pattern provided on said film substrate, including a pair of fixed contact parts opposing each other; a hollow domed elastic spring member including a movable contact part provided on the ceiling thereof, the movable contact part being vertically movable; and a key-top for depressing the top of said elastic spring member; wherein said elastic spring member is mounted on said film substrate so that said movable contact part is disposed over the pair of said fixed contact parts, an air-passage hole is provided in said ceiling having said movable contact part, the air-passage hole being formed in the vertically moving direction of said movable contact part, and air-passage grooves communicating with said air-passage hole are formed in a direction perpendicular to the axis of said air-passage hole, the air-passage grooves being provided at least in one of the positions in said key-top at a portion thereof to be in contact with the top of said elastic spring member and in said elastic spring member at the top thereof, whereby the air in the hollow elastic spring member is discharged, when said key-top is pressed to deform said elastic spring member, to the outside of said elastic spring member through said air-passage hole and said air-passage grooves.