A proximity sensor is a position sensor which can be operated without mechanical contact with moving parts. When the object approaches the sensing surface of the proximity sensor and moves within the motion distance , the sensor can be operated without mechanical contact and any pressure applied to drive the direct current device or the computer ( plc ) device to provide control instructions. The proximity sensor is a switch-type sensor ( i.e . a contactless sensor ) . It carries properties of a travel sensor and a micro sensor. At the same time, it has sensing properties with reliable operation, stable performance, rapid frequency response, long service life, strong anti-interference capability, etc, and is waterproof, shockproof, corrosion resistant, etc. Products include inductance, capacitance, Holzer, AC and DC. 

The proximity sensor, also known as the contactless proximity sensor, is an ideal electronic sensor quantity sensor. When the metal detector is close to the sensing area of the proximity sensor, the sensor will send out electrical instructions quickly without contact, pressure, or spark, accurately reflecting the position and stroke of the motion mechanism. Even for general stroke control, its positioning accuracy, operating frequency, service life, ease of installation and adjustment, and adaptability to harsh conditions can outweigh general mechanical stroke sensors. With wide application in machine tools, metallurgy, chemical industry, textile and printing industries, it can be used as limit, counting, position control and automatic protection links in automatic control system.