Safety interlock switch e.g. for machine system safety door

摘要

The disclosure relates to a safety switch for a protective device serving a machine or system. The safety switch inside a switching head connected to a switch housing is provided with a drive device for a switch actuator (104), the drive device being actuated by a key which can be inserted into or withdrawn from the switching head. The safety switch is provided with a sensor (118) for detecting the presence and absence of the switching head and an actuating system in the switch housing (101). Said actuating system, in the event that the switching head becomes disconnected from the switch housing (101), and controlled by the sensor (118), exerts a force on the switch actuator (104) in the latter's direction of movement against a restoring force; the force exerted by the actuating system is either equal to or greater than said restoring force, depending on whether the switch actuator (104) is to be kept in the position previously adopted or restored to it.