Keyboard switch

A keyboard switch comprising:

• switch sheet means having contact pattern means formed thereon, said contact pattern means constituting switch means;
• a frame formed of metal sheet disposed on one side surface of said switch sheet means, said frame having an opening formed therethrough in an area covering said contact pattern means;
• a pair of first bearing means and a pair of second bearing means formed integrally with said frame by a drawing process, said pairs of first and second bearing means arranged so as to surround said opening and adjacent the periphery of said opening;
• a first link and a second link pivotally connected together intermediate their opposite ends to form a pantograph mechanism and movably engaged at their first ends with said pairs of first and second bearing means, respectively;
• a key top having third and fourth bearing means provided on its bottom surface, the second ends of said first and second links being movably engaged with the corresponding third and fourth bearing means so that said key top is supported by said first and second links for movement parallel to the plane of said frame;
• dome-like switch actuating means formed of rubber disposed within said opening in said frame in opposition to said contact pattern means and adapted to be elastically deformed by downward pressing of the key top to establish electrically conductive continuity through said contact pattern means and to allow the key top to return to its original position when the key top is released;
• and
• a plate formed of sheet metal disposed on the other side surface of said switch sheet means so as to sandwich the switch sheet means between the plate and said frame.