The working principle of the electromagnetic coil

Overview

Solenoid valves are the most commonly used control elements in fluid systems and can be used to cut, release, meter, distribute or mix gases and liquids. Key features include:
■ Fast and safe opening and closing
■ High reliability
■ Long service life
■ The material used has good compatibility with various media.
■ Low power consumption
■ Compact structure
The most commonly used actuators are direct acting actuators, but pivotal armature actuators and rocker actuators are sometimes used.

The working principle of the electromagnetic coil

Although the actuator system, mechanical structure and function are different, the basic components of the various actuators are the same. The main component of the electromagnetic coil is an electromagnet. When a current passes through a wire (such as an enameled wire), a magnetic field is generated around the wire. If the wire is made into a coil, the magnetic field will expand. In addition to the number of turns of the wire and the magnitude of the current, the magnetic circuit around the core of the electromagnetic coil also affects the magnitude of the magnetic force, but in general, the effect of polarity is negligible.

The magnetic field generated by the electromagnetic coil attracts the middle core, also known as the plunger. As long as there is current in the coil, the core will not move. Once the current in the coil disappears, the compression spring returns the core to its starting position.
The material used to make the core must meet the following conditions:
■ Has good magnetization performance
■ Low magnetic storage effect
■ Strong wear resistance
■ Strong chemical resistance
■ Good mechanical operation
The seal on the core ensures the opening and closing of the solenoid valve.