Key switch material selection and characteristics

The characteristics of the key switch, the key switch refers to the switch that uses the button to push the transmission mechanism, press or disconnect the moving contact and the static contact, and complete the circuit replacement. The key switch is a main command electrical appliance with a simple layout and a wide range of applications.

In electrical active control circuits, it is used to manually announce control signals to control contactors, relays, electromagnetic starters, etc. The key switch can complete start, stop, forward rotation, speed change and interlock. Typically, each key 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 move together, the normally closed contacts open and the normally open contacts close.

The principle of key switch

The AC power input enters DC through the rectification filter; the switching tube is controlled by a high-frequency PWM (pulse width modulation) signal, and DC is added to the primary level of the switching transformer; the switching transformer secondary induces high-frequency voltage, and the load is provided through the rectification filter; Certain outputs are fed back to the control circuit through a certain circuit to achieve a stable output. The key switch is a switch with a relatively complex layout, and its components include handles, slides, contacts, terminals, bandage springs, etc. The operation of the key switch is to transmit some keys to the handle, and then the handle controls the contacts and terminals to complete the switch control of the contacts.

There are two types of key switches: single-key switches and multi-key combination switches. The power switch in the TV usually adopts a one-button switch, which is divided into a self-locking self-resetting switch (press this switch to open the self-locking switch, then press the button to open the reset button (press the button to open the reset button), press the button to open the reset button (Press the button to open the reset button).The key combination button to open the key button is divided into self-locking lock type.

Selection of Key Switches

The data used for the key switch is excellent in flame retardancy, insulation, impact resistance and moisture resistance. The raw material has strong stability and is not easy to change color. In addition to high-grade plastics, key switches also have metal materials such as gold-plated, stainless steel, and copper, providing you with more and more choices.