1、 Overview

Magnetostrictive sensor is a high-precision displacement sensor developed based on "magnetostrictive principle". It adopts non-contact measurement method and will not reduce the service life of the sensor due to friction, wear and other reasons. Its good environmental adaptability, reliability and stable work bring great convenience to users. Compared with conductive rubber, LVDT, resistive displacement sensor and other products, it has obvious advantages. Its output signal is a true absolute position output, not a proportional signal or a signal that needs to be amplified and processed again, so there is no signal drift or value change, so it is not necessary to re calibrate and maintain regularly like other displacement sensors; It is precisely because its output signal is an absolute value, so if the power supply is interrupted and reconnected, it will not pose a problem to the data reception, and there is no need to return to the zero position.

2、 Operating principle
The working principle of magnetostrictive sensor is shown in the figure below. The product is mainly composed of a measuring rod, an electronic chamber and a non-contact magnetic ring sleeved on the measuring rod. Magnetostrictive wire (waveguide wire) is installed in the measuring rod. The measuring rod is made of non-magnetic stainless steel tube, which reliably protects the waveguide wire. During operation, an initial pulse is generated by the electronic circuit in the electronic bin. When the initial pulse is transmitted in the waveguide wire, a rotating magnetic field moving along the direction of the waveguide wire is generated. When the magnetic field meets the permanent magnetic field in the magnetic ring, a magnetostrictive effect is generated, causing the waveguide wire to twist. This twist is sensed by the energy pickup mechanism installed in the electronic bin and converted into a corresponding return pulse, The time difference between the start pulse and the return pulse is calculated by the electronic circuit
(like the principle of radar ranging), the measured displacement can be accurately measured.