SU1751699A1 - Apparatus for finding short-circuited turns in inductive members - Google Patents

Abstract

Usage: in the field of test equipment for detecting short-circuited turns in inductive elements. SUMMARY OF THE INVENTION: The device comprises a power source 1, an auto-generator 3 comprising a transformer 5, a matching element 6, a voltage divider 7, a control pulse generation unit 9, a duration analysis block 11, an amplitude analysis unit 10, a switch. 4 and block 12 processing. 1-3-5-6-7-8-9-10-12- 13,9-11-12. Zil.

Description

The invention relates to measuring technique and can be used to detect short-circuited turns in the coils of transformers, inductors and other inductance elements 5 mainly during the manufacturing process.

The aim of the invention is to increase the control performance while maintaining the high reliability of control 10 for various types of inductive elements.

Figure 1 shows a block diagram of the proposed device; in FIG. 2 - stress diagrams at various points of the device; in FIG. 3 - design of the transformer of the oscillator.

The device contains a power source 1, a self-oscillator 2. connected to a power source through a variable resistor 20 3, a transformer 4 on a ferrite core, a matching element 5, the output of which is connected to the input of the voltage divider 6, the output of which is connected via block 7 to block 8 the control pulse, pulse analysis blocks 9 and 10 in amplitude and duration, respectively, whose inputs are parallelized and the outputs are connected to the measurement results processing block 11, and an indication block 30 12.

Figure 2 shows: 13 - voltage diagram at the output of the oscillator: 14 - voltage diagram at the input of the control pulse generation block; 15 - 35 diagram of the voltage at the output of the control pulse forming unit.

The transformer of the oscillator (Fig.Z) consists of a frame that serves to lay the windings of the oscillator - primary 16 and 40 of the control 17, a protective casing 18 that protects the ferrite core 19 from breakdowns, and a secondary winding 20.

The device operates as follows. 45

When the device is turned on, the oscillator generates harmonic oscillations, which are supplied through the transformer 4 (winding III) to the matching element 5. The winding II together with the switch 50 is used to control the operation of the device. A test inductive element is put on the free end of the ferrite core. Variable resistor 3 is used to set the operating mode 55 of the oscillator 2. The operating mode is selected most sensitive to a short-circuited coil on a ferrite core.

After the matching device, the signal of the oscillator is fed to the input of a voltage divider, which is a group of variable resistors connected in parallel and serves to select the level of the signal supplied through switch 7 to the control pulse generation unit 8. The number of resistors is determined by the number and type of tested inductive elements.

Need to select the input signal level of the control formation unit? This impulse is caused by the fact that when donning an inductive element to the free end of the ferrite core, this element introduces the detuning of the self-oscillator. .

Block 8 of the formation of the control pulse generates a pulse of a certain amplitude and duration, which arrives at the pulse analysis blocks of amplitude 9 and duration 10. If there is a short-circuited coil in the tested inductive element, the oscillations of the oscillator are reduced, a complete generation failure is possible, therefore, the control pulse changes its duration and amplitude or completely disappears.

The control pulse analysis units in amplitude 9 and duration 10 generate signals arriving at the measurement result processing unit 11, which, according to the measurement result, gives a signal for indication.

The proposed device allows you to test various types of inductive elements for the presence of short-circuited turns without connecting them to the device and provides high reliability control even in the presence of one short-circuited coil in the inductive element.

Claims (2)

Claim 1. A device for detecting short-circuited turns in inductive elements, containing a power source, a self-oscillator, a transformer with a ferrite core, a processing unit, an indication unit. the power source is connected to the power terminals of the oscillator, the output of which is connected to the primary winding of the transformer, the output of the processing unit is connected to the display unit, characterized in that, in order to increase the monitoring performance. a matching element, a voltage divider, a control pulse generation unit are introduced into it. analysis blocks in duration and in amplitude, switch, transformer secondary winding is connected to the input of the matching element, the output of which is through 5 1751699. the voltage divider and the control pulse generation unit are connected to the inputs of the analysis units in duration and amplitude, the outputs of which are connected to the corresponding inputs of the processing unit, 5 the oscillator contains a circuit for adjusting the excitation threshold, the control winding of the transformer is connected to the closing contacts of the switch. 2. The device according to p. 1, with the exception that in order to increase sensitivity, the transformer is made in the form of a protective casing, in the lower part of which there is a frame with primary and control windings wound on it, inside the protective casing there is a ferrite core with a secondary winding wound on it. ''