電磁閥的定義：電磁閥(Electromagnetic valve)是用電磁控制的工業設備，是用來控制流體的自動化基礎元件，屬于執行器，并不限于液壓、氣動。用在工業控制系統中調整介質的方向、流量、速度和其他的參數。電磁閥可以配合不同的電路來實現預期的控制，而控制的精度和靈活性都能夠保證。電磁閥有很多種，不同的電磁閥在控制系統的不同位置發揮作用，zui常用的是單向閥、安全閥、方向控制閥、速度調節閥等。The definition of solenoid valve: the Electromagnetic valve is an industrial equipment controlled by Electromagnetic control. It is an automatic basic component used to control the fluid. It belongs to the actuator and is not limited to hydraulic and pneumatic. Adjust the direction, flow, speed and other parameters of the medium in an industrial control system. The solenoid valve can cooperate with different circuits to achieve the expected control, and the control precision and flexibility can be guaranteed. There are many kinds of solenoid valves. Different solenoid valves play a role in different positions in the control system. The most common ones are one-way valve, safety valve, directional control valve, speed regulating valve and so on.

電磁閥的原理：電磁閥里有密閉的腔，在不同位置開有通孔，每個孔連接不同的油管，腔中間是活塞，兩面是兩塊電磁鐵，哪面的磁鐵線圈通電閥體就會被吸引到哪邊，通過控制閥體的移動來開啟或關閉不同的排油孔，而進油孔是常開的，液壓油就會進入不同的排油管，然后通過油的壓力來推動油缸的活塞，活塞又帶動活塞桿，活塞桿帶動機械裝置。這樣通過控制電磁鐵的電流通斷就控制了機械運動。The principle of electromagnetic valve, solenoid valve has closed cavity, in a different location to open a hole, each hole to connect different tubing, cavity piston is among, both sides are two electromagnets, which face the magnet coil electricity body which side will be attracted to, through to control the movement of the valve to open or close the different discharge of oil hole, and the oil hole is always open, hydraulic fluid will enter the different oil drain, and then through the oil pressure to push the cylinder piston, piston drives the piston rod, piston rod drive mechanism. This controls the mechanical movement by controlling the electrical current of the electromagnet.

電磁閥的分類：

大體有兩種：
1.電磁閥：采用分步直接式結構，使電磁力直接作用到主閥芯，在壓差等于零或真空時，亦能可靠動作，閥芯磨損能自動補償，大大地延長了使用壽命，低功耗，無泄漏，適用于制冷劑、蒸氣、水、空氣、油、真空等介質。
2. 特種電磁閥：超低溫電磁閥（適用于－196℃液氮）、高溫電磁閥（zui高溫度可達450℃）、防爆電磁閥（得把適用于易爆易燃的危險環境）、塑料王電磁閥（特別適用于酸堿、超凈流體介質）、信號電磁閥、常開電磁閥、單向電磁閥、帶手動電磁閥等。

簡單來講
所有的電磁閥都是將電信號轉成氣的動作（就是信號的轉換）

Classification of solenoid valves:

There are two general types:

1. Electromagnetic valve: the direct structure step by step, the electromagnetic force directly to the main valve core, the differential pressure is equal to zero or vacuum, can reliable action, the valve core can automatically compensate the wear and greatly prolong the service life, low power consumption, no leakage, applicable to the refrigerant, steam, water, air, oil, vacuum, etc.

2. Special solenoid valve: cryogenic solenoid valve (applicable to - 196 ℃, liquid nitrogen), high-temperature solenoid valve (the highest temperature can reach 450 ℃), explosion-proof solenoid valve (have to apply to explosive flammable dangerous environment), plastic king solenoid valve (especially suitable for acid and alkali, super clean fluid), signal solenoid valve, normally open solenoid valve, a one-way electromagnetic valve, electromagnetic valve with manual, etc.

simply

All solenoid valves are the act of converting electrical signals into gas (the signal conversion).