If you want to know how a thing works, you must first understand its structure. Button is a control element with spring and can be automatically reset by manual operation. It is a kind of commonly used master component in control circuit. In the development process of button box, products with indicator light, key hole and emergency brake function are added.
Structure of button switch: the button is generally composed of button cap, return spring, bridge type moving contact, static contact, pillar connecting rod and shell. According to the opening and closing state of the button when it is not affected by external force, it can be divided into start button (normally open button), stop button (normally closed button) and composite button (i.e. button combined with normally open and normally closed contacts).