Abstract: A push-in bulb base for use in a bayonet-type bulb socket. The push-in base does not require turning of the bulb base to engage the retaining bayonets of the bulb base in the L-shaped retaining slot of the bulb socket. The push-in bulb base has integrally formed flexible retainers which flex inward during installation and then flex back to their normal position to engage the L-shaped retaining slots of the bulb socket. An integrally formed alignment rib prevents the bulb base from being inserted into the bulb socket in a position that would prohibit the engagement of the retainer with the L-shaped retaining slot.

Abstract: A machine operator control station circuit which uses capacitive proximity switches to replicate the function of mechanical switches used in prior art control stations. A monitoring circuit for monitoring the "on" state of the capacitive proximity switches used in a two hand industrial machine control station is disclosed. The circuit also reduces the chance of unintended operation of the machine being controlled as a result of emitted or conducted radio frequency interference which might be detected by the capacitive proximity switches. An isolation transformer provides an isolated power supply for the monitoring circuit. The monitoring circuit includes a first capacitive proximity switch for detecting the presence of one of the machine operator's hands, and a second capacitive proximity switch for detecting the presence of the other of the machine operator's hands. Each proximity switch has a monitoring circuit for monitoring the length of time the proximity switch remains in the activated or "on" state.

Abstract: The rotational optical switch of the present invention includes a switch enclosure, a light conductor, an optical shutter, a torsion spring biasing the shutter towards a bistable state, and a shutter actuator. The switch enclosure generally encloses the remaining components. The light conductor is received in the switch enclosure and extends between the enclosure and a transceiver, which provides a signal reflective of the state of the optical shutter. The optical shutter is pivotally mounted within the switch enclosure and is bistable between a reflective state which reflects light into the light conductor, and a nonreflective state which does not reflect light into the light conductor. The shutter pivots on arms to either end of a support cylinder which have knife edges. The shutter actuator is pivotally connected to the optical shutter by the torsion spring to cause the optical shutter to snap between the bistable states. The optical shutter has two reflectors in opposite reflective states.