The operating principle of a magnetostrictive displacement sensor is based on the magnetostrictive effect, whereby a ferromagnetic material expands or contracts under the influence of an external magnetic field and returns to its original length when the external magnetic field is removed. Specifically, the sensor consists of a waveguide, a movable magnetic ring, and an electronics chamber. During measurement, the excitation module in the electronics chamber generates a current pulse. This pulse propagates through the waveguide, creating a circumferential magnetic field around the waveguide. When this magnetic field intersects with the magnetic field generated by the movable magnetic ring mounted on the waveguide, a mechanical strain wave pulse signal is generated inside the waveguide due to the magnetostrictive effect. This mechanical strain wave pulse signal propagates at a fixed speed and is quickly detected by the electronic chamber. Since the propagation time of the mechanical strain wave pulse signal within the waveguide is directly proportional to the distance between the movable magnetic ring and the electronic chamber, this distance can be determined by measuring the time, thereby enabling high-precision displacement measurement.

The following are the detailed steps of how a magnetostrictive displacement sensor works:

1. The excitation module in the electronic chamber generates a current pulse, which propagates through the waveguide and creates a circumferential magnetic field.

2. The magnetic field generated by the movable magnetic ring interacts with the circumferential magnetic field, triggering the magnetostrictive effect and producing a strain mechanical wave pulse signal.

3. The mechanical strain wave pulse signal propagates at a fixed speed and is detected by the electronic chamber.

4. By measuring the time difference and combining it with the wave velocity, the position of the moving magnetic ring is precisely calculated, thereby determining the displacement of the measured object.

Magnetostrictive displacement sensors, characterized by high precision, high reliability, long service life, and maintenance-free operation, are suitable for various harsh environments and complex application scenarios.