Why can electric kettles automatically power off?

Many families have used itElectric kettleThey are also often seen in hotels. The electric kettle is very convenient to use. When the tap water is loaded and the switch is pressed, the water will automatically turn off when it boils. The ability of the electric kettle to automatically turn off the power depends entirely on a material called bimetallic sheet.

1. Substances generally have the characteristics of thermal expansion and contraction, especially metals, but different metals have different coefficients of expansion. After increasing the same temperature, some metals show significant changes in thermal expansion, while others show no significant changes.

If a special fusion process is used to fuse two metal sheets with different expansion coefficients together, they will bend in one direction during heating and expansion, called bimetallic sheets.

3. Install the bimetallic sheet in a temperature sensitive area. When the water temperature in the electric kettle reaches 100 degrees, the bimetallic sheet bends to a certain extent, pushing some mechanical transmission components, forcing the switch to open and cut off the circuit.
4. Bimetal sheets have low cost and high reliability, and are widely used in situations where temperature control circuits need to be disconnected, such as rice cookers, ovens, and air switches.
FemaleAccording to practical applications, there are three or more types of metal fusion materials, which we still habitually refer to as bimetallic sheets.