How does the rice cooker know whether the rice is cooked?

There is a magnetic control device in the center of the heating plate of the rice cooker. There is a magnet inside. Its Curie point is 105 degrees. When it reaches 105 degrees, the magnet will temporarily lose its magnetism. The magnetic control device, the switch and the hand button form a magnetic control device. Switch. The surface of the heating plate is designed to be spherical, and the pot is low enough to fit it. When you put down the pot and press the button, the magnet will close, and the switch will be turned on. The water will be heated until it is almost cooked and the rice will be absorbed. But it is not complete yet. Dry. Since the pot is low and the center is high, there is no water first, and the stability rises to 105 degrees. [It cannot rise to 105 degrees when there is water] The magnet loses its magnetism, and the switch jumps. The rice is cooked by the residual heat of the heating plate. .A bimetallic temperature control switch is also connected in parallel to the magnetic switch. Its control point is 65 degrees for automatic heat preservation. The principle of the new rice cooker is similar, but with the addition of electronic time control.