Switch apparatus including a pair of beam-type switches

Abstract

A manually operable switch apparatus for a machine having at least one mode of operation actuated by a control circuit includes a spaced pair of switches which are simultaneously manually operable without the application of exertive contact by an operator. Preferably, each switch includes an infrared emitter spaced from an infrared receiver, and a single or double pole, double throw relay actuated when the beam between the emitter and receivers are broken, so as to cause actuation of an alternative mode of machine operation. The use of switches which do not require exertive contact obviates the injury to wrist and finger tendons experienced by machine operators when conventional palm buttons are employed on machines requiring repetitive operator manipulations. The use of a spaced pair of such switches requires that the operator place both hands on the switches in order to operate the machine, so that the operator cannot inadvertently place a hand in or adjacent to the machine during operation, thus serving to prevent injury to the worker. Such a switch apparatus is substantially more reliable then conventional mechanical and pneumatic switches, subject to significantly less breakdown in use.

Dependencies are inferred from the claim text.