Safety operating switch for Brinel testing machine - uses foot operated switch comprising proximity sensor for releasing machine function

摘要

The foot-operated switch comprises a proximity switch, responding to the proximity of the operator's foot and eliminating the need for direct contact. Pref. the proximity switch has a sensor responding to the proximity of a safety shoe. The machine may have a recess into which the operator's safety shoe can be inserted, the base of the recess containing a proximity sensor for the safety shoe. The proximity sensor pref. uses a HF coil exhibiting an inductance variation in response to the proximity of the safety shoe. ADVANTAGE - High safety factor at relatively low cost.