Oven thermostat

Claim 1

A TEMPERATURE RESPONSIVE CONTROL DEVICE COMPRISING A HOUSING, AN EXPANSIBLE MEMBER ADJUSTABLY MOUNTED IN ONE WALL OF THE HOUSING, SAID MEMBER EXPANDING AND CONTRATING ACCORDING TO THE DIRECTION AND EXTENT OF TEMPERATURE CHANGE OF AN EXTERNAL BODY, AND MANUAL CONTROL MEANS COMBINED WITH THE EXPANSIBLE MEMBER FOR SETTING THE DESIRED TEMPERATURE OF THE DEVICE, FIXED SWITCH CONTACT MEANS MOUNTED WITHIN THE HOUSING, A SNAP-ACTING SPRING MECHANISM SUPPORTING MOVABLE SWITCH CONTACT MEANS, SAID SPRING MECHANISM BEING MOTIVATED BY THE EXPANSIBLE MEMBER FOR MAKING AND BREAKING AN ELECTRIC CIRCUIT THROUGH THE FIXED CONTACTS, AND A LOCK-OUT MECHANISM FOR DISABLING THE MOVABLE CONTACT MEANS IN AN OPEN CIRCUIT POSITION ONCE THE TEMPERATURE REACHES A PREDETERMINED MAXIMUM TEMPERATURE, SAID LOCK-OUT MECHANISM INCLUDING AN INSULATING PLATE CONNECTING THE SNAP-ACTING SPRING MECHANISM WITH THE MOVABLE CONTACT MEANS, A SPRING-BIASED PAWL SUPPORTED IN THE HOUSING FOR MOVEMENT TOWARD AND AWAY FROM THE SAID INSULATING PLATE, SAID PLATE INCLUDING A KEEPER PORTION THAT IS ADAPTED TO BE ENGAGED BY THE PAWL IN ONE POSITION OF THE CONTROL DEVICE FOR LOCKING THE MOVABLE CONTACT MEANS IN THE OPEN CIRCUIT POSITION, AND AN ADJUSTABLE CAMMING MEANS COMBINED WITH THE EXPANSIBLE MEMBER FOR COOPERATION WITH THE PAWL SO THAT IN ONE NORMAL POSITION THE PAWL IS HELD AWAY FROM THE SAID PLATE, ANOTHER POSITION OF THE EXPANSIBLE MEMBER AND HENCE THE CAM FREEING THE PAWL THEREFROM WHEREBY WHEN THE EXPANSIBLE MEMBER REACHES ITS POSITION OF MAXIMUM TEMPERATURE THE INSULATING PLATE MOVES UNTIL THE PAWL IS LOCKED THEREWITH TO PREVENT SUBSEQUENT CLOSING OF THE CONTACTS UNTIL THE POSITION OF THE EXPASIBLE MEMBER AND HENCE THE CAMMING MEANS IS CHANGED.