Abstract: An automatic switch actuator is disclosed which may be used to test press-to-actuate type switches--for example, the key actuated switches of a computer keyboard. In the illustrated embodiment of the invention, a system of electrically operated valves are used to apply four different fluid pressures to selected pistons of an array of pneumatic cylinders. Each cylinder is mechanically connected to a plunger which is oriented so as to contact a selected key in an array of keys (i.e., a keyboard).

Abstract: A keyboard actuator for actuating the keys of a keyboard-operated apparatus including a plurality of fluid latching actuators supported to controllably and selectively actuate a key. In the preferred embodiment, each fluid actuator includes a latch and a piston. In response to fluid pressure, the latch releases the piston and the piston may be driven to actuate a key of the keyboard-operated apparatus. No return spring is used to cause a piston rod to rise to a position where it can be latched. The upward action of normally operative key effects the return of the piston rod to achieve latching.

Abstract: A keyboard actuator for actuating the keys of a keyboard-operated apparatus including a plurality of fluid actuators supported by a frame, a first plurality of fluid conduits in communication with one or more selected fluid actuators, and first and second valve means for applying fluid pressure to selected ones of the first and second plurality of fluid conduits in response to signals from the control means. The fluid actuators include latching means and piston means. In response to fluid pressure, the latching means releases the piston means and the piston means may be driven to actuate a key of the keyboard-operated apparatus.