SU746351A1 - Apparatus for investigating magnetic-field topography - Google Patents

Description

(54) DEVICE FOR RESEARCH OF TOPOGRAPHY The invention relates to instrument engineering, it can be used to study the topography of magnetic fields. Devices are known that contain 1 power supply source, Hall sensors and Arithmetic, block 1. The disadvantage of such devices is low measurement accuracy. Of the known devices, the device closest to the technical essence of the invention comprises a power source, a phase shifter, a measuring probe with two perpendicularly arranged Hall sensors, and a coordinate stand 2. The disadvantage of these devices is low measurement accuracy. The purpose of the invention is to increase the measurement . This goal is achieved by the fact that a device containing a series-connected power source, a phase shifter and a measuring probe with two perpendicular Hall sensors, the input of the first of which is connected to the output of the power source, and the input of the second Hall sensor is connected by the output of the phase shifter, as well as the coordinate the stand, the output of the MAGNETIC FIELDS of which is connected to the third input of the measuring probe, two keys are introduced, connected in series, an adder, an amplifier, a rectifier And an indicator, the first input ummatora through the first switch connected to Yield first Hall sensor and the second input of the adder via a second switch coupled to an output of the second Hall sensor. The drawing shows the structure of a device for studying the topography of magnetic fields. The device contains a power source 1, a phase shifter 2, a measuring probe 3 with two perpendicularly located sensors W 4 and 5 Hall, keys 6 and 7, an adder 8, an amplifier 9, a rectifier 10, an indicator 11, a coordinate stand 12. The device works in the following way. Through the Hall sensor 4, which is connected directly to the power source 1, a current flows where 3 is the amplitude of the current; Yiw - frequency.

Between the second Hall sensor 5 and the power supply source 1, the phase shifter 2 is turned on, which shifts the current phase by goal 5i72, therefore the instantaneous power supply value of the second sensor varies in time according to the law -tg (t) jj coswt. In the study of topography, the measuring probe is placed on its floor in such a way that its axis, and hence also the plane of the sensors, are perpendicular to the plane of interest.

In this case, at the output of the sensors, the voltages and, (t) and MlH () vary in time according to the laws

. V W K | B | co5pJ-sinwt-B KJ sinu) t, (1)

4i, x) sin J costot b KJj cosott j L 2)

where K is the sensitivity coefficient of the sensors;

| In | | - module of the magnetic induction vector in the studied point of the plane;

p is the smallest angle between the normal to the plane of the first sensor and the magnetic induction vector at the studied point; . 6, B - normal and tangential components of the magnetic induction vector.

The voltages Udh and Ud arrive through the keys B and 7 at the inputs of the adder 8, the output voltage of which, with the keys closed, is proportional to the modulus of the magnetic induction vector

Uj. (T) Kt8 | J Sin (uyt + 45; (3)

A measuring block, consisting of a series-connected amplifier, rectifier and indicator a, is connected to the output of the adder. Depending on which keys are closed, the indicator registers, without changing the position of the measuring probe, the magnitude of the modulus, tangential and normal components of the magnetic induction vector in the explored point of the plane. ,

When the position of the probe 12 is changed with the help of the coordinate stand 12, the magnitude of the modulus and the relative magnitude of their magnetic induction vector is measured, i.e. The topography of the magnetic field is investigated.

 Introduction to the device of two keys connected in series adder and two inputs of the amplifier, rectifier and indicator, as well as connecting the output of the first Hall sensor through the first key to the first input of the adder, and the output of the second Hall sensor through the second key to the second input of the adder allows at the output of the adder, electrical signals whose voltage is proportional to the modulus or components of the magnetic induction vector (depending on the position of the keys). The subsequent processing of these .electric; the signals in the amplifier and the rectifier make it possible to record by the indicator, without changing the position of the probe and without additional calculations, the magnitudes of the modulus and components of the magnetic induction vector.

The proposed device makes it possible to reduce the laboriousness of the process of studying the topography of magnetic fields by a factor of 3–4 compared to existing devices and significantly reduces the influence of subjective factors on the results of the study.

Claims (2)

The invention The device for the study of the topography of magnetic fields, containing sequentially connected source of power, phase shifter and measuring probe with two perpendicular Hall sensors, the input of the first of which is connected to the output of the power source, and the input of the second Hall sensor connected to the output of the phase rotator, as well as coordinate stand, the output of which is connected to the third. 0 by the input of the measuring probe, in order to improve the accuracy of the Measurement, two keys are inserted into it, connected in series with an adder, amplifier, rectifier and indicator, the first input of the adder being connected via the first key to the output of the first Hall sensor and the second input of the adder through the second key is connected to the output of the second Hall sensor. Sources of information taken into account during the examination 1. N. Fevraleva. Hard magnetic materials and permanent magnets. KiHaykova Dumka, 1969, p. 110. ev, 55 2. USSR author's certificate No. 152193, cl. G 08 C 9/04, 1961.