CN1063164A

CN1063164A - Remote sensing tester for coil short-circuit

Info

Publication number: CN1063164A
Application number: CN 91100314
Authority: CN
Inventors: 袁贞高; 章妙富
Original assignee: EAST CHINA ELECTRIC WELDING MACHINE FACTORY
Current assignee: EAST CHINA ELECTRIC WELDING MACHINE FACTORY
Priority date: 1991-01-12
Filing date: 1991-01-12
Publication date: 1992-07-29

Abstract

The invention provides a kind of Growler; coil constitutes detecting head on bar magnet; the signal frequency that signal source adopted can make short-circuited coil produce maximum echo; therefore sensitivity is very high; detecting head need not and contacted by test coil during test; the detecting head of the tester before having overcome must coincide and be only applicable to the shortcoming of coil such as motor windings with tested iron-core coil; this tester is applicable to all kinds of coils; the coil that comprises no iron core and magnetic core; and can carry out on-line testing; also has anti-electric shock apparatus, with protection user's safety.

Description

Remote sensing tester for coil short-circuit

The present invention relates to the whether instrument of short circuit of a kind of test coil, relate in particular to a kind of instrument that adopts the short circuit of remote sensing technique test coil.

Chinese patent CN86200310 discloses a kind of middle and small motor short circuit in winding tester, it comprises test pulser, detecting head, short circuit signal amplifier and audible-visual annunciator, the principle of this instrument application electromagnetic coupled is tested, therefore when test, need detecting head is contacted with the motor windings iron core, placed restrictions on its range of application.

The object of the present invention is to provide a kind of highly sensitive, easy to use, can non-destructive testing the remote sensing tester for coil short-circuit of all kinds of coils.

Another object of the present invention is to provide a kind of remote sensing tester for coil short-circuit that can differentiate and call user's attention safety whether charged by test coil.

A further object of the present invention is to provide a kind of short circuit remote sensing tester of online coil, can test the coil that is connected in the circuit, and need not pull down coil, and this coil might form the loop with external circuit.

Designer of the present invention finds in test, all kinds of short-circuited coils produce tangible echo to the signal in this frequency range of 31.23～38.17MHz, therefore if measuring signal generator produces the signal in this frequency range, just can improve tester sensitivity greatly, thereby detecting head need not and contacted by test coil, as long as near by test coil.

Fig. 1 is the block scheme of remote sensing tester for coil short-circuit provided by the invention.

Fig. 2 is a kind of circuit diagram of realizing Fig. 1 block scheme.

Fig. 3 is the simplified electrical circuit diagram of signal generator and detecting head in Fig. 2 circuit.

Be described in detail the present invention below in conjunction with accompanying drawing.

Referring to Fig. 1, wherein detecting head 2 is by transmitting coil L₁, receiving coil L₂, bar magnet 11 forms two coil L₁And L₂On same bar magnet 11. It is the sine wave of 31.23～38.17MHz that measuring signal generator 1 produces frequency, by the transmitting coil L on the detecting head 2₁Test signal is outwards launched, and as being had short circuit phenomenon by test coil, short circuit and the coil sections closed-loop path that forms produces an echo is positioned at the receiving coil L on the detecting head 2₂Obtain this echo, this echo amplifies through the shaping of echo-signal shaping amplifier 5, drive circuit 10 drives optical display unit 6 corresponding light emitting diodes according to the amplitude level of amplifying the back echo signal through shaping, with the various degree of expression coil short, notifies the user by acoustic alarm device 7 simultaneously.

Because coil can be sneaked into foreign material in winding process, these foreign material might cause coil short, this short circuit can be eliminated by suitable means, coil can be utilized again, between this short circuit and circle and the circle, the echo amplitude that forms of direct short-circuit between layers is different, so drive circuit 6 can drive the different short-circuit conditions of corresponding diode displaying according to the different amplitudes of echo. The optical display unit 6 of present embodiment adopts secondary to show, to distinguish above-mentioned two kinds of situations. The echo-signal that same coil single turn short circuit and a few circle short circuit produce also has power, thereby the also degree of available a plurality of diode displaying coil shorts as required. Because when external circuit made coil form the loop, echo-signal was very big, its amplitude is greater than the short circuit of ordinary circumstance, so drive circuit 10 can be distinguished according to the amplitude of output signal after the shaping amplification.

As shown in Figure 1, this tester also adds a protection against electric shock circuit 8, is positioned at induction pole 9 on the detecting head 2 from being obtained coil charged signal by test coil, produces by protection against electric shock circuit 8 and drives signals, drive acoustic alarm device 7 sounding and dichromatic LED D variable color, call user's attention safety. Its principle illustrates according to Fig. 2, when by test coil with can jeopardize the alternating current of human body the time, induction pole 9 can obtain a signal, this signal adds to fet BG1 grid, makes fet BG1 conducting, also makes transistor BG4 conducting, dichromatic LED D₄Variable color, and driving acoustic alarm device 7 sounding, charged with the reminding user coil, acoustic alarm device 7 adopts CP13, KD13 as source of sound, under normal circumstances, the loudspeaker Y of acoustic alarm device 7 sends the sound of the source of sound that KP13 provides, when this instrument detects coil and has short circuit, 5 ends of CMOS9013 link to each other with the B point of CP13, make CP13 work.

Fig. 2 is a kind of physical circuit of block diagram shown in Figure 1, driving circuit 10 adopts the CMOS9013 integrated circuit, help reducing machine volume, the output signal of shaping amplifier 5 is delivered to 2 ends of CMOS9013, the output signal of protection against electric shock circuit 8 is delivered to 3 ends of CMOS9013, acoustic alarm device 7 adopts CP13, KD13 as source of sound, light emitting diode D ₁Be green, for this tester relay indicating light is held concurrently by the normal pilot lamp of test coil, because the incoming level that CMOS can be different according to 2 ends, in 10 ends and 8 ends output low level or be high level etc. simultaneously respectively, therefore, the light emitting diode D of yellow ₂Be connected with 10 ends of CMOS9013, represent when bright by the short circuit of test coil, red D owing to foreign material cause ₃Be connected with 8 ends of CMOS9013, represent tested coil short when bright, D ₂, D ₃When all not working, the expression coil does not have short circuit.

Fig. 3 is a measuring signal generator 1 and the circuit diagram of detecting head 2 through simplifying in the present embodiment.Adopt a kind of self-excited oscillation circuit in the present embodiment, because transmitting coil L ₁With receiving coil L ₂Be wound in the same way on the same bar magnet 11, therefore produce strong tight coupling, make circuit constantly produce self-sustained oscillation, oscillation frequency can be passed through capacitor C ₁Regulate, it is dropped in the 31.23-38.17MHz scope, the signal that vibration produces forwards launch along bar magnet 11, as if the place ahead had short circuit phenomenon by test coil, this short-circuited coil will produce an echo, coil L ₂Receive this echo, form a modulation signal at the A point, this modulation signal passes through capacitor C ₁Add to triode BG ₂Base stage, the signal that A is ordered is delivered to shaping amplifier 5.When the measuring signal frequency was 34.7MHz, effect was best, and present embodiment promptly adopts this frequency.

The power supply of this tester adopts No. 5 batteries of two joints, to reduce the volume of instrument, is easy to carry, and also can adopt external power supply.

Claims

1, a kind of Growler, be made up of measuring signal generator 1, detecting head 2, echoed signal shaping amplifier 5, driving circuit 10, optical display unit 6 and/or acoustic alarm device 7 and power supply, the signal frequency that it is characterized in that the measuring signal generator generation is in 31.23～38.17MHz scope.

2, Growler as claimed in claim 1, the optimum frequency that it is characterized in that test signal is 34.7MHz.

3, Growler as claimed in claim 1 is characterized in that detecting head 2 is by being wound with transmitting coil L ₁With receiving coil L ₂Bar magnet 11 form transmitting coil L ₁With receiving coil L ₂Coiling in the same way.

4, as claim 1 or 2 or 3 described Growlers, it is characterized in that also having the protection against electric shock circuit, be positioned at induction pole 9 on the detecting head 2 from by the test coil picked up signal, this signal adds to fet BG1 grid, make fet BG1 conducting, dichromatic LED D ₄Variable color, and drive acoustic alarm device 7 sounding.