Lost motion keyswitch

Claim 1

A lost motion keyswitch comprising a housing having a bottom wall and an open upper end, a plunger having a tubular body extending downwardly in the housing and slidably engaging said housing for movement up and down therein, means limiting upward travel of the plunger to a predetermined elevated position, the lower end of said plunger body being spaced above said bottom wall while the plunger is in said elevated position, a pair of opposed spring contact strips extending through said bottom wall and projecting below it to form terminals, the contact strips also converging upwardly inside the plunger and having upper ends urged toward engagement with each other, a shuttle loosely disposed inside the plunger body and provided with a cross member extending between the contact strips, the inside of the plunger being provided with means for supporting the shuttle while the plunger is in said elevated position, and a coil spring inside the plunger below said shuttle-supporting means and encircling the contact strips but spaced therefrom, said spring normally holding the plunger in said elevated position with said cross member spreading the upper ends of the contacts apart, the plunger being provided with means normally spaced above the shuttle for moving the shuttle downwardly after the plunger has been depressed a predetermined distance, and the inner side of each contact strip being provided with a projection extending substantially from the point of engagement of the strip by the raised cross member downwardly a predetermined distance to hold the contacts apart until the descending cross member slides off the lower ends of said projections.