The temperature controller is made according to the principle of heat expansion and cold contraction of objects. Heat expansion and cold contraction are common objects, but different objects have different degrees of heat expansion and cold contraction. The two sides of the double gold sheet are conductors of different substances, which bend the double gold sheet at the changing temperature due to different degrees of expansion and contraction, and touch the set contact or switch, so that the set circuit (protection) begins to work.
This is the basic working principle and production idea of temperature controller.