The push button switch (English name: push-button switch) refers to a switch that pushes the transmission mechanism with a button to make the movable contact and the static contact open or close and realize circuit switching. The push button switch is a main electric appliance with a simple structure and a wide application.
In the electrical automatic control circuit, it is used to manually send out control signals to control contactors, relays, electromagnetic starters, and the like.
basic introduction
There are many types of button switches, which can be divided into ordinary button type and mushroom head type.
Self-locking, self-resetting, rotary shank, with indicator light, illuminated symbol and key type, etc. [1] has single button, double button, three button and different combinations, generally using modular structure. It consists of a button cap, a return spring, a bridge contact and a casing. It is usually made into a composite type with a pair of normally closed contacts and normally open contacts. Some products can increase the number of contacts by series connection of multiple components. There is also a self-contained button that automatically holds the closed position when pressed and can only be turned on after a power failure.
The push button switch can perform basic control such as start, stop, forward and reverse, shifting, and interlocking. Usually each push button switch has two pairs of contacts. Each pair of contacts consists of a normally open contact and a normally closed contact. When the button is pressed, the two pairs of contacts act simultaneously, the normally closed contact opens, and the normally open contact closes.
In order to indicate the function of each button and avoid misoperation, the button caps are usually made into different colors to distinguish them, and the colors are red, green, black, yellow, blue, white, and the like. For example, red indicates a stop button, green indicates a start button, and the like. The main parameters, type, mounting hole size, number of contacts and current capacity of the push button switch are described in detail in the product manual.