SU905892A1 - Magnetic core testing device - Google Patents

Description

The invention relates to computing and automation and can be used to measure parameters and take characteristics.

; ring magnetic cores,

especially miniature.

The closest technical solution to this invention is a device for monitoring magnetic cores, which contains a continuous needle, removable contacts, an excitation current pulse generator,

A measurement circuit and two adjustable air transformers to compensate for the various components of interference 1.

The disadvantages of this device are a high level of interference, since air transformers do not allow them to fully compensate, and the difficulty of setting up the device.

The purpose of the invention is to increase the reliability of the control.

This goal is achieved by the fact that in a device for controlling magnetic cores containing an excitation current generator, a measuring continuous needle with removable contacts and a measuring unit, through a transformer connected to the needle, the excitation current generator is connected to a continuous needle with a constant contact and one removable current contact located at the ends of a continuous needle, between which three potential contacts with the test core between two of them are placed evenly, and these The contacts are connected to two input windings of the transformer, connected in series with each other and all the way, with the connection point of the input windings connected to the middle potential contact, and the beginning of the input windings connected to the remaining two potential contacts.

The present device, thanks to the use of three removable potential contacts of the differential transformer, allows considerably, for example, 100 to 200 times, to reduce the level of interference and to simplify tuning.

25

The drawing shows a device for monitoring magnetic cores,

The device contains the excitation current generator 1, which through the resistor 2, a constant contact 3 and

removable current contact 4 is connected to measuring continuous needle 5. Potential removable contacts 6 are evenly distributed along needle 5 between current contacts 3 and 4. Two extreme potential removable contacts 6 are connected to the beginning of two input windings 7 and 8 of transformer 9. Ends of these windings 7 and 8 are interconnected and with the average potential contact 6, The test core 10 is placed between two potential removable contacts b, To the output winding I of the transformer the measuring unit 12 is connected.

The device works as follows.

In the absence of the test core 1.0, the generator 1 of the excitation current with the help of a resistor 2 creates the necessary alternating excitation current, which through contacts 3 and 4 goes to the measuring needle 5. The potential removable contacts b are evenly distributed, so that the voltage between the middle and upper contacts 6 is equal to the voltage between the lower and middle contacts 6. These two voltages are fed to two input windings 7 and 8 of the transformer 9, which are connected in series and all the way. As a result of subtracting the input voltages on the output winding 11, a slight EMF noise is induced ..- In the presence of the test core 10, one of the windings (according to the drawing on the winding 8) additionally receives an EMF determined by the magnetic properties of the core 10, on the output winding 11 and falls on the measuring unit 12. As an instrument, an oscilloscope, an electronic voltmeter, can be used. etc. With a symmetrical arrangement of the extreme potential contacts 6 with respect to the average EMF, the interference on the output winding 11 is in the order of 1 10 μV, no less. The number of turns of the windings 7 and 8 W1 W2 11, windings 11-- W3 58. Almost the entire setting of this

the device is reduced to simg the location of potential contacts 6.

The device is intended for screening miniature magnetic cores with an external diameter (0.61 mg) used as analog storage elements with non-destructive reading information. Such elements are characterized by a low output level (in the order of 1 mV) and existing monitoring devices do not allow to screen them fairly accurately.

Claims (1)

1. Tsaplin D.V. The contact system of the machine for screening ferrite cores. Exchange of experience in radio communication-merger. Issue 3, 1979, p. 58 - 60, fig. 6 t t2