CN2212209Y

CN2212209Y - Circuit fault detector of motor vehicle

Info

Publication number: CN2212209Y
Application number: CN 94230111
Authority: CN
Inventors: 于福海
Original assignee: Individual
Current assignee: Individual
Priority date: 1994-08-31
Filing date: 1994-08-31
Publication date: 1995-11-08
Anticipated expiration: 2004-08-31

Abstract

The utility model relates to a detecting device used for searching the fault of the circuit part of a vehicle quickly, comprising a testing part for a circuit fault and a voltage testing part, wherein, the voltage testing part is a voltage comparator which comprises double differential circuits and which detects high and low potential. The detecting device has multi detecting functions, high detecting precision, and convenient and easy use.

Description

Circuit fault detector of motor vehicle

The utility model relates to and be used for quick judgement, search motor vehicle, particularly the pick-up unit of the circuit part sources of trouble such as automobile, motorcycle, tractor and boats and ships.

For the driver, motor vehicle " casting anchor on the way " is headachy thing, particularly the fault that partly occurs of the motor circuit people that do not enrich service experience is difficult to find the source of trouble, and service kit is auxiliary to be able to on-call maintenance if having this moment, will greatly facilitate the driver.People at first utilize multimeter to detect, and are relatively heavier because of its volume is big though multimeter is multiple functional, use very inconvenient.In the Chinese patent literature once repeatedly with regard to this field the related detection technology was disclosed, " the automobile-used circuit detector " of Chinese patent CN91211041, it is test signal to be amplified through amplifying circuit drive audio oscillator circuit warning formation, this circuit only has whether the testing circuit live wire has whether electricity, generator generate electricity, the simple function of circuit and switch on and off, but can't detect fault under-voltage in the circuit or that overvoltage causes; " the motor vehicles tester " that another Chinese patent CN88218343 provides, having fault concurrently detects, the function of voltage detecting, this tester has the voltage detecting circuit of same composition by multichannel and forms by being serially connected with the connecting and disconnecting of the circuit testing circuit that direct supply upper flow resistance forms, wherein each road voltage detecting circuit all is made up of switch triode, set different voltage benchmarks by the current-limiting resistance of the different resistances that connect on the base stage, giving signal by the light emitting diode that is serially connected with each road ce utmost point shows, though this tester circuit structure is fairly simple, but wherein added direct supply, use inconvenience, and utilize the switch performance of triode to carry out voltage detecting, precision is low, and electronic component is more.In view of this, the defective that existing motor circuit pick-up unit exists makes it very undesirable in the use.

Goal of the invention of the present utility model is to provide a kind of intuitively automobile circuit fault-signal, have multifunctional detecting device simple in structure, a kind of motor circuit fault detector circuit test and voltage tester, that can accurately detect that has concurrently particularly is provided.

The motor circuit fault detector that the utility model provides, comprise fault part of detecting, voltage tester part and function switch and be used to obtain the detecting head of detection signal, it is characterized in that dual-electricity-limiting pressure ratio that voltage tester partly is made up of two difference channels than the circuit cross-over connection between detecting head, respectively by the positive of two difference channels, reversed-phase output to fault part of detecting output action signal; Be provided with driving circuit between fault part of detecting and the voltage tester part.

In this programme,, adopt the constant current source difference channel to form the dual-electricity-limiting pressure ratio in the operating voltage part of detecting than circuit for further improving the voltage detecting precision of this detecting device.

The motor circuit fault detector of technique scheme, the signal of detecting head input both had been the power supply signal of this circuit, was again the test signal of this circuit, had created condition for the simplification of circuit, had made things convenient for the detection of motor vehicles in travelling again; Because its voltage tester partly adopts difference channel, zero point drift and the low problem of comparison precision that common valve threshold voltage switching tube circuit exists have been eliminated, improved common-mode rejection ratio, reduced the detection error, and setting voltage limit value with the need, utilize switch can realize that the fault of multiple function detects again; Utilize sound and light alarm, show more directly perceived.

Fig. 1 is the circuit theory diagrams of this motor circuit fault detector

Fig. 2 is the profile state figure of this motor circuit fault detector

Specify the utility model detecting device below in conjunction with above-mentioned accompanying drawing:

As shown in the figure, this motor circuit fault detector comprises fault part of detecting, operating voltage part of detecting, function switch K and detecting head, wherein detecting head is divided into probe 1 and the shim 2 that links to each other with ground, the detection signal that probe 1 imports is as the original signal of circuit working, and shim 2 can directly link to each other with the motor vehicle shell and obtain ground signalling; Wherein the fault part of detecting can be used for audible alarm for the audio oscillator circuit of various ways, in the present embodiment, has adopted typical stable multi-oscillation circuit, and its output terminal drives news Chinese percussion instrument HTD load.When function switch K with after J links to each other, shim 2 ground wires, can carry out the fault detect of quality, circuit breaker or the short circuit of various relays, switch, fuse, bulb, and by light emitting diode D1, pilot lamp 8 Homeway.com Chinese percussion instruments 5 among Fig. 2 be should give audible alarm mutually, realize the detection of fault.

Another major part of the present utility model is the operating voltage part of detecting, two differential voltage comparator circuits that it is made up of identical difference pipe V10, the V11 of parameter and V20, V21, form the dual-electricity-limiting pressure ratio than circuit, by resistance R 01～R04 and stabilivolt D as core _WThe reference circuit cross-over connection that constitutes between detecting head, two component volt circuit R _W1, R1 and R _W2, the R2 cross-over connection between probe 1 and shim 2 wiring, and respectively by its dividing potential drop node E, F to two difference comparator circuit input voltage comparison signals, change resistance R _W1, R _W2Be used to adjust the voltage limit value; By with reference edge A respectively positive, anti-phase two output terminal M, N point out the difference comparison signal, be used for driving circuit fault test part.For improving the driving force of this voltage comparator circuit, output terminal M, N link to each other with the base stage of miniwatt PNP driving tube V01, V02 respectively, drive the audio oscillator circuit of circuit test part by the amplifying signal of the ce utmost point, different photochromic light emitting diode D01, D02 of two pipe ce utmost point loops serial connections wherein give acousto-optic jointly with news Chinese percussion instrument HTD in the audio oscillator circuit and show.

In the present embodiment, in order further to improve the common-mode rejection ratio of difference channel, improve the voltage detecting precision, adopt the constant current source difference channel in the above-mentioned voltage comparator circuit, promptly constant current tube V1, V2 are respectively as the constant current source of difference channel V10, V11 and V20, V21.

Switch 6 among function switch K Fig. 2 is linked to each other with the I end, promptly be connected with the voltage comparator circuit positive source.Probe 1 links to each other with the positive source of vehicle battery or dynamo governor, and the A point of this input voltage in reference circuit forms the reference voltage V of two difference channels _A, the E on bleeder circuit, F point forms corresponding comparative voltage V _E, V _F, compare with A point reference voltage simultaneously.Under-voltage as inserting battery tension when probe 1, V then _F＜V _A, V _A＞V _E, the output potential that M point and N are ordered makes driving tube V01 end respectively, makes pipe V02 by by transferring conducting to, starts the news Chinese percussion instrument HTD sounding in the audio oscillator circuit, makes red light emitting diodes D02 conducting, and pilot lamp 3 is luminous, sends under-voltage indication; When the regulation voltage of battery tension that is obtained by probe 1 or dynamo governor is higher than operate as normal pressure value, this moment V _E＞V _A, V _A＜V _F, then M point current potential changes low by height, and N point current potential keeps electronegative potential, and driving tube V01 makes gold-tinted diode D01 conducting by by transferring conducting to, and pilot lamp 4 is luminous, and news Chinese percussion instrument HTD reports to the police, and expression voltage has surpassed the operate as normal value.Detect whether battery tension normal, whether the regulation voltage of generator in normal range.

In the present embodiment; as shown in drawings; for guaranteeing that this detector circuit body element is not destroyed by reverse voltage under the situation of probe 1 access reverse voltage; be connected a unidirectional conducting diode D2 between probe 1 and the function switch K; be connected the reverse-voltage protection circuit that a current-limiting resistance R3 and a reverse protection diode D3 form between probe 1 and the shim 2, by pilot lamp 7 luminous demonstrations.

Claims

1, a kind of motor circuit fault detector, comprise fault part of detecting, voltage tester part, function switch (K) and detecting head (1,2) form, it is characterized in that voltage tester partly is by two difference channels (V10, V11, V20, V21) the dual-electricity-limiting bit comparison circuit cross-over connection that constitutes is between detecting head, by resistance (R01～R04) and stabilivolt (D _W) constitute its reference voltage circuit, two groups of resistor voltage divider circuits (RW1, R1, R respectively from cross-over connection in detecting head between (1,2) _W2, R2) dividing potential drop node (E, F) import comparative voltage separately, and respectively with reference edge (A) homophase, anti-phase output difference actuating signal driving circuit fault test part.

2, detecting device according to claim 1 is characterized in that guaranteeing the accurate of test for improving the comparison precision of voltage tester part, adopts the constant current source difference channel in the voltage tester part.

3, detecting device according to claim 1 and 2 is characterized in that also being connected between the detecting head (1,2) reverse-voltage protection circuit (D2, D3, R3).