SU756327A1 - Residual magnetization measuring device - Google Patents

Description

The invention relates to the field of magnetic measurements. The device, for example, can serve to control parameters interrelated with the residual magnetization.

A device is known in which the residual magnetization is measured using a fluxgate magnetometer after the sample is magnetized with a permanent magnet [1].

The disadvantages of the known devices are the presence of moving elements and the effect of the magnet field on the measurement results.

There is another device in which the residual magnetization is measured using a magnetometer, and the sample is magnetized by a magnetizing winding connected to a source of magnetizing current [2].

This device is subject to external magnetic fields, which, when examining samples of soft magnetic materials, are commensurate with the desired ones, which reduces the measurement accuracy.

In order to improve the accuracy of emulsion in a device containing a magnetizing winding connected to

2

a source of magnetizing current, an integrator, a key, a demagnetizing winding consisting of two identical, connected in series parts arranged symmetrically with respect to the axis of the magnetizing winding, and a source of demagnetizing current, and an integrator connected to a magnetizing winding

Squeeze through the key, and the demagnetizing winding is connected to the source of the demagnetizing current.

The windings are placed on the W-shaped symmetric magnetic core in the region

Contact with the sample, the distance between its poles decreases from the center to the edges, and the turns of the magnetizing winding are distributed along the rods of the magnetowire in proportion to

20 drops of magnetic stress on them and equally on the extreme rods.

FIG. 1 shows a block diagram of a device for measuring residual magnetization; in fig. 2

25 and 3 show the relative position of the windings with different shaped samples; in fig. 4 - the location of the windings on the magnetic core; Figure 5 shows the shape of the poles of the magneto30 wire (section A — A of Figure 4).

756327

A device for measuring residual magnetization contains a magnetizing winding 1 connected to a source of magnetizing current 2, a switch 3 for connecting to the magnetizing winding of integrator 4, a demagnetizing winding 5 consisting of two identical parts' 6-1 and 6-2, and a source of demagnetizing current 7 to which the demagnetizing winding is connected.

FIG. Figures 2 and 3 show the possible positions of windings 1 and 5 relative to the measured samples 8, the arrows on windings 1 and 5 coincide with their axis and for half of the demagnetizing winding 5 show the direction of the magnetic flux at a certain point in time.

The device works as follows.

First, the sample 8 is magnetized using a current pulse transmitted through the magnetizing winding 1 from the source of the magnetizing current 2. Then the integrator 4 is connected to the magnetizing winding 4 using a key 3 and the sample is demagnetized using a winding 5 through which the alternating, decreasing amplitude current. After degaussing the sample, an indication proportional to the value sought is obtained from the integrator.

The placement of the windings 1 and 5 on the W-shaped symmetric magnetic core 9 increases the sensitivity of the device and the accuracy of the measurements carried out near the lower boundary of the measured parameters. This is due to the fact that the magnetic circuit reduces the magnetic resistance, through which the residual magnetic flux closes, determined by the residual magnetization and this resistance.

When working on flat samples exceeding the size of the magnetic core 9, the latter is advisable to perform so that in the area of contact with the sample the distance between the poles 10, 11, 12 decreases from the middle to the edges due to the approach of the poles of the extreme rods to the middle. This reduces the size of the magnetized area due to less vybuchivanija flow of magnetization in the sample to the side of the poles of the magnetic circuit and, therefore, reduces the effect of the edge of the sample on the measurement with asymmetric installation of the magnetic circuit, for example near the edge of the sample. Reducing the influence of the edge is equivalent in this case to reducing the error.

The distribution of the turns of the magnetizing winding 1 along the rods of the magnetic conductor 9 is proportional to the drops of the magnetic voltage on them reduces the scattering fluxes during magnetization due to the fact that the magnetomotive force becomes distributed along the magnetization circuit more evenly.

Claims (2)

Claim 1. A device for measuring residual magnetization containing a magnetizing winding connected to a source of magnetizing current, characterized in that, in order to improve accuracy, an integrator, a key, demagnetizing winding consisting of two identical parts connected in series, are inserted into it symmetrically with respect to the axis of the magnetizing winding, and a source of demagnetizing current, with the integrator connected to the magnetizing winding through a key, and the demagnetizing winding connected to the source demagnetizing current. 2. Device by π. 1, characterized in that the windings are placed on the W-shaped symmetric magnetic core in the contact area of the magnetic circuit with the sample, the distance between its poles decreases from the center to the edges, and the turns of the magnetizing winding are distributed across the magnetic cores in proportion to the magnetic voltage drops on them and equally on the extreme rods .