Micro-switch is a kind of fast switch actuated by pressure, also called sensitive switch. A kind of main electric appliance with short stroke and instantaneous action. Micro-switch is a small contact switch, which can be turned on with a light touch of the hand. It is often used in factories to protect the short circuit and overcurrent inside the big switch. When the external mechanical force acts on the operating button, the operating button moves downward and the spring is stretched through the retractor.