SU842651A1 - Method of magnetic field measuring - Google Patents

Description

(54)

SENSOR OF A GRADIENT OF A MAGNETIC FIELD

one

The inference relates to the technique of magnetic measurements and is intended to measure the tradition of magnetic fields .5

Magnetic field gradient sensors are known that contain two galvanomagnetic transducers spaced apart from each other in space by a certain exactly measured distance. The Hall electrodes of the transducers are included in the opposite way. The output signal when the sensor is placed in the measured magnetic field is proportional to the induction gradient of this field 1.

The disadvantage of this sensor is low sensitivity and accuracy of measurements.

A summer cottage is also known for measuring the gradient of a magnetic field, which contains two semiconductor parallel-arranged strips interconnected by a conductive jumper. The semiconductor strips are made of magitoresistive material and, together with the conductive bridges, are attached to a ceramic substrate. The output signal is differential from two signals, proportional to the values of semiconductor resistances, strips, depending on the magnitude of the magnet.

FIELD in their locations. The difference in induction values divided by the distance between the strips (gradiometer base) is taken as a measure of the magnitude of the gradient of the magnetic field 12.

The disadvantage of this device is the low measurement accuracy.

The purpose of the invention is to improve the measurement accuracy.

To achieve this goal, a magnetic field gradient sensor, containing two transducers in the form of semiconductor parallel strips connected by a conductive jumper and a support, is provided with two other elements, each of which is connected to a support and with a corresponding semiconductor strip made of a thermal resistance material.

The drawing shows a sensor for measuring a magnetic field gradient, a general view.

The sensor contains two semiconductor parallel strips 1 of thermo resistive material, conducting a jumper 2, elastic elements 3 connecting the semiconductor strips with the support 4.

The sensor works as follows. .

Through semiconductor strips 1,: A jumper 2 and conductive elastic elements 3 transmit a direct current in the case of alternating and alternating in the case of a constant magnetic field. The Ampere force acts on each arm consisting of the stripe and the conducting elastic element. In an inhomogeneous field, L T, acting on each arm, are different in magnitude and their resultant acting on a mechanical system consisting of two arms, connected by a conducting bridge 2, causes the system to oscillate, which is possible; due to the attachment of semiconductor strips 1 to the support 4 by elastic elements 3. Under the action of vibrations, the semiconductor strips are cooled in the environment, which leads to a change in their resistances D R and, consequently, the voltage of the lines 2 JUR. The output signal di, which is linearly dependent on the equalities 1 | e | 1 of the force f F, and, therefore, on the magnetic field induction difference in places located along the plane divided by the gradiometer base (the length of the passing crossover 1 point), determines the gradient of the magnetic field. .

Replacing in the proposed sensor for measuring the magnetic field gradient with semiconductor strips made of magnetoresistive material with semiconductor strips made of thermal resistance material and replacing the rigid attachment to the support by elastic with elastic conductive elements significantly increases the sensitivity and accuracy of measurements when the output signal is linearly dependent on the magnetic field gradient.

Claims (2)

1. Afanasyev Yu. And others. Magnetometric converters, devices, installations. L., Energie, 1972, p. 226. 2.Vayos G. Physics of galvanomagnetic semiconductor devices and their application. M.,: Energy, 1972, with. 265.