SU842666A1 - Device for checking part demagnetization - Google Patents

Description

I

The invention relates to measurement instrumentation and can be used to measure the magnetic fields of solenoids, conductors with current, to determine the level of residual magnetization of parts made of ferromagnetic materials in the course of nondestructive magnetic control.

A device for controlling the demagnetization level of parts is known, which contains a power step-down transformer, an electronic stabilizer on a two-cathode zener diode, an evoA magitouprav contact (reed switch) pushed inside the magnetic coil, adjustment resistance and indicator light.

Adjusting resistance, connected in series with the magnetizing coil, sets the required level of sensitivity.

C1.

However, the use of the simplest electronic stabilizer (voltage) on a two-anode Zener diode does not provide sufficient for precise measurements of the stability of a magnetic magnetizing field;

also leads to measurement instability.

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

This purpose is achieved in that a device containing a series-connected indicator and a magnetic contact placed inside the biasing coil is an alternating voltage generator, through a first switch connected to the indicator, a stabilizer whose input and output are connected via a second switch , connected to the input of the stabilizer and parallel to the biasing coil, two-section resistors connected in series with the biasing coil, a balance electronic key was inserted, he first input of which is connected to the output regulator, the output is connected to the bias coil and adjusting the two resistors, and the second input key associated with the alternator output voltage.

The drawing shows a functional diagram of the device.

Claims (2)

The device consists of an autonomous power supply 1; an indicator 2 connected in series with a reed switch 3 (a magnetically controlled contact placed inside the magnetizing coil 4, three switches 5-7 capacitors 8 and 9, electronic stand, id, generator 11 alternating voltage, electronic key 12 and TWO, adjusting resistors 1.1 and 1. The voltage of the power source 1 through the switch 5 is fed to the generator. 1.or 11, producing rectangular pulses with a frequency of 3-6 Hz and through the switch 6 of the type of work, having three groups of contacts a, bi c, a, electronic stabilizer 10 pa The capacitor 8 is connected in parallel with the input. Switch 6 can be in two positions: OP.A. and Demagnetize. In the Work position, contact a and "1kt, bi with open. In the Demagnetize position, contact a is open, bis contacts closed. Contact b connected to the output of the stabilizer 10, the stabilized voltage from which, via the electronic key 12, is applied to the adjusting resistors 13 and 14, the biasing coil 4. The symmetrical outputs of the generator 11 are connected to the corresponding inputs of the electronic key 12. Generation It controls the PRs and elektron.nym key 12, assembled in a bridge circuit, and Katushev ke 4 passes an alternating current rectangular shape. In parallel with the coil, a capacitor 9 is connected, which is necessary for smoothing the pulses differentiated by the coil. In parallel with the adjusting resistor 14 is connected to the switch 7. The device operates as follows. To prepare the device for operation, it is necessary to connect switch 5, switch 6 to the Work position. The capacitor 8 is charged until the voltage of the source 1 of the power supply., The generator 11 starts producing square impulses, and the electronic bridge key 12 commutes the stabilized voltage, creating an alternating current in the coil 4 and an alternating magnetic field corresponding to the magnetizing reed switch 3, which can have residual magnetization. To eliminate its influence on the accuracy of measurements, the reed switch 3 needs to be de-magnetised. Switch 6 should be turned to Degauss position. In this case, the capacitor 8 begins to discharge, and contact c increases the frequency of the generator 11 by a factor of 5 to 10. An alternating voltage with an exponentially decreasing amplitude is formed on the magnetizing coil 4. The switching of the capacitor 8 through the contact b directly to the input of the stabilizer 10 is carried out with the aim of creating the maximum magnetic field at the initial moment of demagnetization, the reed switch 3. Next, the switch 6 is switched to the Operation position, with which the capacitor 8 is charged again. Switch 7 is connected to the shunt of the adjusting resistor 14, and the reed switch 3 is moved in the earth's magnetic field, until the adjusting resistor 13 is moved so that the indicator and the light come on and go out. When Orienting the longitudinal axis of the reed switch along magnetic field lines, it closes, the indicator light flashes, and when perpendicular to the reed switch, indicator 2 is open and open. Then switch 6 is opened and the reed switch 3 is placed in a reference coil with a demagnetization level . The reed switch system - the reference coil is also moved in the Earth's magnetic field, until the resistor 14 has been turned on so that the indicator light comes on and goes out. Then the reed switch is removed from the reference coil. The device is ready to measure. When measuring, if the intensity of the controlled magnetic field exceeds the selected limit level, the reed switch 3 closes, the circuit of the indicator circuit 2. The invention The device for controlling the demagnetization of parts, containing an indicator connected in series and a magnetically controlled contact, placed inside the biasing coil, an alternating voltage generator, through a first switch connected to the indicator, a stabilizer, the input and output of which are connected through a second switch connected to the input of the stabilizer and parallel to the biasing coil, two control resistors connected in series with the biasing coil, in that, in order to increase the accuracy of control, it is additionally introduced balanced eloktronny key, the first input of which is connected to the output regulator, the output is connected to the bias coil and two adjusting resistors ,: and the second input key associated with vyhrdom alternator voltage. Sources of information taken into account in the examination 1. New physical methods of non-destructive quality control of products. Conference materials, MDNTP them. F.E. Dzerzhinsky, M., 1977, pp.142-145.