Timed electric switch

Abstract From the Canadian patent

A timed electric switch in a housing preferably for direct current loads such as for heating elements in vehicle windows, in which manually closable contacts supply current to the load and also to a timing circuit which may be digital which completes a circuit through a holding solenoid for the contacts. After a predetermined time or count has been achieved in the timing circuit, the current supply through the holding solenoid, is interrupted thereby releasing the contacts. Provision is also made for allowing the second and subsequent timing periods to differ from the first timing period such as by independently supplying a potential to the timing circuit, such as through the vehicle …