Patent ID: 6064020
Filing Date: 2000-05-16
Classification: H01H

Abstract:
A key switch comprising:a contact part which closes when pressed down;a housing disposed above said contact part;an elastic member disposed above said contact part for closing said contact part when pressed down and wherein said elastic member returns to an initial condition when released;a key top disposed above said elastic member, wherein said key top has a back surface;a first link member having a first engaging part rotatably engaged with said key top, a second engaging part slidably engaged with said housing, and a rotation fulcrum disposed at a center between said first engaging part and said second engaging part;a second link member having a third engaging part slidably engaged with said key top, and a fourth engaging part rotatably engaged with said housing, wherein said second link is rotatably engaged with said rotation fulcrum of said first link member at a center between said third engaging part and said fourth engaging part;wherein said first link member and said second link member are nested in each other in one plane when said key top is pressed down;wherein one of said first link member and said second link member is disposed inside the other, and wherein said elastic member is disposed inside both said first link member and said second link member;wherein said first link member and said second link member are formed in a frame-like shape; anda stopper provided on said back surface of said key top, wherein a part of said second link member is butted against said stopper when said key top ascends, and wherein said stopper has a height which sets a force required for disengaging said key top from one of said first and second link members to a desired strength.