Because the displacement sensor can be made according to different principles and different methods, without
Inductance type proximity switch
The same displacement sensor on the object of the "perception" method is also different, so the common proximity switches have the following:
Passive Proximity switch
This switch does not require a power supply, through magnetic induction control switch closed state. When the magnetic or iron trigger is close to the switching magnetic field, the internal magnetic force of the switch controls the closure. Features: No power, non-contact, maintenance-free, environmental protection.
Eddy Current Type Proximity switch
This switch is sometimes called an inductive proximity switch. It is the use of conductive objects near this can produce electromagnetic field close to the switch, the inside of the object generated eddy current. The eddy current reacts to the proximity switch, which changes the internal circuit parameters of the switch, thereby recognizing that there is no conductive object moving close to the control of the switch's pass or break. The object that the proximity switch can detect must be a conductive body.
1. Principle: By inductance coil and capacitor and transistor composition oscillator, and produce an alternating magnetic field, when a metal object close to this magnetic field will produce eddy current in the metal object, resulting in oscillation stop, this change is amplified after the conversion into a transistor switch signal output.
2. Features: A, good anti-interference performance, high switching frequency, greater than 200HZ. B, can only induction metal
3. Used in a variety of mechanical equipment for position detection, counting signal pickup.