Push-button switch is a kind of press - to - action, release - to - reset used to switch on and off the small current circuit electrical equipment. Generally used in AC and DC voltage below 440V, current less than 5A control circuit, generally do not directly control the main circuit, can also be used in the interconnected circuit. There are many kinds of button switch structure, which can be divided into ordinary snap button type, mushroom head type, self-locking type, self-reset type, handle type, with indicator light type, with lamp symbol type and key type. There are single button, double button, i button and different combination forms. Generally, the water structure is used, which is composed of button cap, reset spring, static contact, moving contact and shell. It is usually made into compound type, with a pair of normally closed contact and normally open contact. Some products can increase the logarithm of contact through a plurality of components in series. There is also a self-supporting button, which can be automatically kept closed after being pressed, and can only be opened after power failure. In this article, the button switch manufacturer Yingshang Microelectronics mainly explains the button switch composition structure chart.
The structure of Push Button Switch: composed of button cap, reset spring, fixed contact, movable contact, shell and pillar connecting rod. The main categories are as follows:
1, normally open (dynamic) button switch, not pressed down, the contact is disconnected, pressed down when the contact closed through; When released, the push-button switch is reset and disconnected under the action of the reset spring. In the control circuit, normally open button is commonly used to start the motor, also known as the start button.
2, normally closed contact (breaking contact): refers to the original state (electrical equipment is not subjected to external force or coil is not energized), fixed contact and movable contact
Point the contact in the closed state.
3, normally closed (break) button switch and normally open button switch, the last press, the contact is closed, press the contact is disconnected; When the hand is released, the button switch is reset and closed under the action of the reset spring. Normally closed button is often used to control motor stop, also known as self-reset button.
4, normally open contact (dynamic contact): refers to the original state (electrical equipment is not subjected to external force or coil is not energized), fixed contact and movable contact
Point the contact in the separated state.
5, composite button switch: normally open and normally closed button switch combination into one of the button switch, that is, with normally closed contact and normally open contact. When not pressed down, normally closed contact is closed, normally open contact is disconnected. When the button is pressed, the normally closed contact is first disconnected, and the normally open contact is closed, which can be considered as a self-locking button; When the button switch is released, under the action of the reset spring, the normally open contact is first disconnected, and then the normally closed contact is closed. Composite buttons are used in interlocking control circuits.
