SU1283646A1 - Electromagnetic transducer - Google Patents

Abstract

The invention relates to non-destructive testing and can be used to control the quality of ferromagnetic objects. The purpose of the invention is to improve the control accuracy and to obtain a signal in a discrete form-me — achieved by reducing the transducer instability by using a second set of jumpers with a measuring winding. Electromagnetic transducer is installed so that one of its circuits interacts with a controlled part, and the other with an exemplary one. With the same magnetic properties of both parts, the readout of the reversible counter does not change. If the magnetic properties are different, the number of pulses produced by the remagnetization of jumpers in the respective circuits of the magnetic circuit will be different. This difference is proportional to the difference in the magnetic properties of the parts and is recorded by a reversible counter. 1 il. ®

Description

N9

00 WITH Od 4 O)

The invention relates to non-destructive testing and can be used to control the quality of ferromagnetic objects.

. The purpose of the invention is to improve the accuracy of control and receive the signal in a discrete form.

The goal is achieved by reducing the transducer instability by using a second set of jumpers with a measuring winding.

The drawing shows an electromagnetic converter.

The converter contains a double-circuit magnetic circuit 1 made of a material with a magnetisation curve ensuring its operation on a linear portion of the magnetization curve. A central winding 3 is placed on the central core 2 of the magnetic circuit 1. In both magnetic circuits, sets 4 and 5 of jumpers are made of a material with a rectangular hysteresis loop. Sets 4 and 5 of the jumpers are covered, respectively, by measuring windings 6 and 7. One circuit of the magnetic circuit 1 is closed by a controlled ferromagnetic part 8, and the other - by-10

15

20

25

a similar process takes place, but the output pulses in the measuring windings have the opposite polarity. These pulses are fed to the inputs of the limiter amplifiers 10 and II, and then the positive pulses are immediately, and the negative ones after insertion are HE elements 12 and 13 input elements OR 14 and 15 The output pulses of one channel from the stroke of the element OR 14 are fed to the summing input, and the other channel of the output of the element OR 15 is the subtracting input of the reversible counter 16 pulses. Thus, in both of the sawtooth current periods, bursts of pulses arrive at the input of the counter.

If the magnetic resistances of the part to be turned 8 and the reference part 9 are equal, then the magnetic fluxes of the circuits of the magnetic circuit are the same. Therefore, equal to the number of jumpers in sets 4 and 5, i.e. the number of pulses induced in windings 6 and 7 is the same. In the result of the reversal counter of the 16 pulses, O is recorded.

When changing the characteristics of koi

detail 9. Measuring objj of the part to be rolled 8 changes its

35

40

skeins 7 and 8 are connected to the inputs of limiting amplifiers 10 and 11, the outputs of which directly and through the elements NOT 12 and 13 are connected to the inputs of the elements OR 14 and 15. The output of the element OR 14 is connected to the summing element, and the element OR 15 - to to the subtractive inputs of the reversible counter of 16 pulses.

The limiting amplifiers 10 and II, the elements are NOT 12 and 13, the elements OR 14 and 15 form two identical pulse shapers.

Electromagnetic converter works as follows.

The exciting winding 3 powers-from the saw-tooth generator 17. Magnetic flux occurs in the magnetic circuit 1, which closes in one circuit through the set 4 jumpers and monitored item 8, and in the other through set 5 jumpers and sample 9. As a result of remaking the jumpers in the measuring windings 6 and 7, bursts of pulses, with the number of pulses in the bursts being determined by the number of paramagnetic jumpers. When changing the polarity of the sawtooth current

magnetic resistance, which causes a redistribution of the magnetic flux between the circuits. At a constant current amplitude in the exciting volume 3, this leads to an increase in the number of remagnetized jumpers in one circuit and a decrease in the other. As a result, the counter 16 records the difference in the number of pulses, which uniquely determines the value of the controlled parameter.

Changes in the amplitude of the current of drift and temperature lead to identical increments of magnetic fluxes in the circuits and, therefore, do not affect the value of the output code recorded in the reversible counter 16.

Claims (1)

Invention Formula Electromagnetic transducer containing exciting winding, two-circuit magnetic circuit, made of material with induction for saturation, ensuring its operation in a linear part of the magnetization curve, a set of jumpers from a material with a rectangular hysteresis loop, placed in one of the contours ten 15 20 25 a similar process takes place, but the output pulses in the measuring windings have opposite polarity. These pulses are fed to the inputs of the limiting amplifiers 10 and II, and then the positive pulses are directly, and the negative ones, after inversion, by the elements HE 12 and 13 arrive at the inputs of the elements OR 14 and 15. The output pulses of one channel from the output of the OR 14 element are fed to the summing input, and the other channel from the output of the OR 15 element — the subtracting input of the reversible counter of 16 pulses. Thus, in both half-periods of the sawtooth current, bursts of pulses arrive at the counter inputs. If the magnetic resistances of the monitored part 8 and the model part 9 are equal, then the magnetic fluxes in the circuits of the magnetic circuit are the same. Therefore, an equal number of jumpers in sets 4 and 5 are magnetized, i.e. the number of pulses induced in windings 6 and 7 is the same. As a result, O is recorded in the reversible counter of 16 pulses. When the characteristics of the co-controlled part 8 change, its magnetic resistance, which causes a redistribution of the magnetic flux between the circuits. When the current amplitude is constant in the exciting winding 3, this leads to an increase in the number of magnetized jumpers in one circuit and a decrease in the other. As a result, counter 16 records the difference number of pulses that uniquely determine the value of the monitored parameter. Changes in the magnitude of the switching current and temperature lead to the same increments of the magnetic fluxes in the circuits and therefore do not affect the value of the output code recorded in the reversible counter 16. Invention Formula Electromagnetic transducer containing exciting winding, two-circuit magnetic circuit, made of material with saturation induction, ensuring its operation in the linear part of the magnetization curve, a set of jumpers made of material with a rectangular hysteresis loop, placed in one of the contour 1283 and measuring The core of the magnetic circuit, the winding encompassing a set of jumpers, and the exciting winding are placed on the central core of the magnetic circuit, characterized in that, in order to increase the accuracy of measurement and obtain a signal in discrete form, it is equipped with a second set of jumpers similar to the first. installed in another circuit of the magnetic circuit, the second measuring winding covering the second set of jumpers, a reversible pulse counter connected by inputs to the outputs of the respective measuring windings through identical pulse shapers. 57 1 II //