Temperature compensated time-delay switch

An actuator device for controlling the supply of power to a load as a function of a physical characteristic to be measured comprising:

• a housing;
• an electrical circuit mounted in said housing including a relay and a sensor for measuring said physical characteristic electrically connected between the supply of power and the load;
• a first bimetallic strip element mounted in said housing with one end fixed and the other end free to move in response to temperature change, thermally coupled to a heat accumulator element;
• a Positive Temperature Coefficient (PTC) heater element adapted to be connected in said electrical circuit to apply heat to said heat accumulator element upon being energized in said electrical circuit;
• a second bimetallic strip mounted in said housing with one end fixed and the other end free to move in response to temperature change;
• arranged adjacent to the first bimetallic strip element;
• and apart from said heat accumulator element to be subject primarily to only the environmental temperature, connector means for providing for mechanically linking of movement between said first and second bimetallic strip elements, a transfer mechanism positioned to be movable upon movement of said first bimetallic strip element and switching means for connecting and disconnecting said supply of power to said load actuatable upon a force applied by said transfer member.