Proximity Switch is a common industrial automation sensing device used to detect whether an object is approaching or leaving.
Proximity switches have the characteristics of non-contact detection and can achieve fast and accurate detection and feedback without touching the object being detected.
What is the working principle of proximity switch?
Proximity switches mainly detect objects by using electromagnetic induction, optical principles or ultrasonic waves.
The most common types of proximity switches are as follows:
1. Proximity switch
When the object to be detected approaches the sensing head, the magnetic field around the sensing head changes, and this change causes a change in the inductance inside the detection coil, thereby triggering a switching action.
2. Infrared sensor
When the object to be detected is close to the infrared sensor, the infrared beam will be reflected and scattered by the object, thereby changing the intensity and frequency of the light signal received by the detector, thereby achieving detection and triggering switch actions.
3. Ultrasonic sensor
This type of proximity switch uses the reflection of sound waves between the object and the sensor to detect the distance of the object.
When an object approaches an ultrasonic sensor, the sensor emits a beam of high-frequency sound waves, and then calculates the distance between the object and the sensor by receiving the time difference between the returned signals.
What are the application fields of proximity switches?
Proximity switches are widely used in industrial automation, machinery manufacturing, logistics and transportation and other fields.
1. Automatic door control
Using a proximity switch or infrared sensor, the door can be opened or closed automatically without manual touch, improving the convenience and safety of entering and exiting the door.
2. Production line control
Proximity switches can be used to monitor whether objects on the conveyor belt are operating normally, such as automatically starting and stopping the equipment after detecting that the object reaches a designated location to ensure the smooth operation of the production line.
3. Conveyor device control
By using proximity switches, the unloading operation can be automatically triggered when the goods arrive at a specific location, improving logistics efficiency and reducing manual intervention.
4. Machine safety control
Install proximity switches in key parts of the machine so that the machine can be shut down in time when an abnormality occurs to ensure the safety of operators.
Summarize
Proximity switches realize non-contact detection of objects through electromagnetic, optical or ultrasonic principles, and can be used in many fields, such as automatic door control, production line control, logistics device control, etc.
