CN2398639Y

CN2398639Y - Intelligent inductometer

Info

Publication number: CN2398639Y
Application number: CN 99225184
Authority: CN
Inventors: 赵文成
Original assignee: Shenyang Institute of Aeronautical Engineering
Current assignee: Shenyang Institute of Aeronautical Engineering
Priority date: 1999-10-09
Filing date: 1999-10-09
Publication date: 2000-09-27
Anticipated expiration: 2009-10-09

Abstract

The utility model relates to an intelligent inductometer which is a necessary universal meter for pursuing jobs of electronics, electrotechnician, household appliances maintenance, etc. The intelligent inductometer is formed by the mode of taking an 89C51 SCM as a core and then being matched with an oscillation circuit and a liquid crystal display. A measured electrical inductance Lx, together with two reversers, forms a multivibrator; an output end of the multivibrator is directly connected with a pin of a timing count port T1 of the SCM 89C51, and collects signals input from the pin; a concrete numerical value of the measured electrical inductance Lx is obtained through calculation processing. The utility model has the advantages of wide measuring range, high resolution and self calibration, and is totally divided into seven measuring range segments. The power supply voltage changes between 3.6 volts and 8.0 volts; the measurement precision is scarcely affected.

Description

Intelligent inductance table

The utility model relates to a kind of intelligent inductance table, is the versatility instrument of being engaged in technician's indispensability of scientific researches such as electronics, electrician and experiment and work such as instrument and meter and home appliance repair.

At present, what sold on the market is digital inductance table all, on principle, is the digital analog mixed system.This system is in case design is definite, its function expansion is very difficult, have to be provided with a range shelves of working hard again in addition, bring many troubles to actual measurement, for a unknown in advance inductance, maximum theoretically measurement number of times equals its range shelves number, and this suffers untold misery for measure batch really.

The utility model utilizes singlechip technology, makes the secohmmeter intellectuality, and the wide-range that it had, high-resolution, self-alignment superperformance are that prior art can't realize.

To achieve these goals, the utility model has adopted following technical scheme: in the intelligent inductance table of wide-range, high-resolution, self calibration, just export a frequency and the big or small relevant pulse signal of outside tested inductance so outside tested inductance and the internal circuit of table are formed the oscillatory circuit back oscillatory circuit that powers on.System not hard to imagine is to be that core is mixed oscillatory circuit again and LCD is formed with the 89C51 single-chip microcomputer, and concrete circuit connecting relation is: tested inductance L _xForm a multivibrator with two reversers, two reversers can be taken from six reverser 74HC04, resistance R ₄An end and tested inductance L _xWith given capacitor C ₀An end link to each other resistance R ₄The other end be connected with (1) pin of six reverser 74HC04, (2) pin of six reversers links to each other with its (3) pin, simultaneously and tested inductance L _xThe other end link to each other.(4) pin of six reversers and given capacitor C ₀The other end connect.This end is the output terminal of multivibrator simultaneously.The timer counter mouth T of the output terminal of multivibrator and one-chip computer 89C51 ₁Pin directly links to each other, and one-chip computer 89C51 gathers the signal of this pin input, through computing, obtains measured capacitance L _xConcrete numerical value, this value is by the P of single-chip microcomputer 89C51 ₀Mouth output is sent apparent.One-chip computer 89C51P ₀Eight pins of mouth link to each other with the input pin of a slice XOR gate CD4030 with three liquid crystal driver CD4543 respectively, and concrete annexation is: single-chip microcomputer 89C51P ₀The P of mouth ₀₀, P ₀₁, P ₀₂, P ₀₃Be connected with individual position, input pin A, the B of hundred liquid crystal driver CD4543, C, D pin respectively, and P ₀₄, P ₀₅, P ₀₆, P ₀₇Then be connected with input pin A, B, C, the D of ten liquid crystal driver CD4543 respectively, so that the normal position measured, ten, hundred of showing.Kilobit of measurement result " 1 " and radix point are controlled by XOR gate CD4030.Three input pins of CD4030, promptly (8), (5) and (1) pin respectively with single-chip microcomputer 89C51P ₁The P of mouth ₁₀, P ₁₁, P ₁₂Connect, so as from three corresponding output terminals of CD4030 promptly (3), (4), (10) pin obtain kilobit numerical value and radix point the measurement result, like this under the control signal effect, just can be with complete the showing of measured result.Control signal is by write signal WR and the address bus signal P of single-chip microcomputer 89C51 ₂The P of mouth ₂₆, P ₂₇Combine together, concrete annexation is: the P of single-chip microcomputer 89C51 ₂₆Pin connects input pin (1) past and door 74HC08, P ₂₇Link to each other with the input pin (5) of 74HC08, the write signal WR pin of single-chip microcomputer 89C51 then is connected with the input pin (5) of six reverser 74HC04, output pin (6) then links to each other with above-mentioned two other input pin (2) and pins (3) with door respectively, two with output pin (3) and pins (6) then be connected with the control pin (1) of three liquid crystal driver CD 4543 respectively.Other two reversers and the resistance R of 74HC04 ₁, R ₂And capacitor C ₀Form another multivibrator together, for liquid crystal driver provides display drive signals, circuit theory is with last identical.

Tested inductance L _xScope be 0.00VH-19.99H, being divided into is seven range sections:

0.00VH-19.99VH

19.9VH-199.9VH

199VH-1999VH

1.99MH-19.99MH

19.9MH-199.9MH

199MH-1999MH

1.99H-19.99H

Native system can be according to tested inductance L _xSize, in measuring process, automatically change range.Measuring method is: after system powers on, automatically carry out school zero, to overcome the influence of system wiring inductance to measuring accuracy, by the time show at 0.00 o'clock, can normally measure.The normal measurement only needs test pencil is clipped in tested inductance L _xTwo ends, system just can measure and show automatically.

The utility model is owing to adopted intellectualized technology, and its characteristics are: 1, wide-range, measurement range: 0.00VH-19.99H.2, whole measuring process need not manual intervention, but automatically changes the range shelves under Single-chip Controlling.But 3, power on after automatic zero adjustment, with the distributed inductance that overcomes instrument itself tested inductance is produced measuring error.4, change between 3.6 volts-8.0 volts of the supply voltages, and measuring accuracy is influenced hardly.

The utility model is described in further detail below in conjunction with specific embodiment and accompanying drawing.

Fig. 1 is a block diagram of the present utility model.

Fig. 2 is an electrical schematic diagram of the present utility model.

Fig. 3 is the structural representation of the utility model housing.

With reference to Fig. 1,2, system is to be that core is mixed oscillatory circuit again and LCD is formed with the 89C51 single-chip microcomputer, and concrete circuit connecting relation is: tested inductance L _xForm a multivibrator with two reversers, two reversers can be taken from six reverser 74HC04, resistance R ₄An end and tested inductance L _xWith given capacitor C ₀An end link to each other resistance R ₄The other end be connected with the 1st pin of six reverser 74HC04, the 2nd pin of six reversers links to each other with its 3rd pin, simultaneously and tested inductance L _xThe other end link to each other.The 4th pin of six reversers and given capacitor C ₀The other end connect.This end is the output terminal of multivibrator simultaneously.The timer counter mouth T of the output terminal of multivibrator and one-chip computer 89C51 ₁Pin directly links to each other, and one-chip computer 89C51 gathers the signal of this pin input, through computing, obtains tested inductance L _xConcrete numerical value, this value is by the P of single-chip microcomputer 89C51 ₀Mouth output is sent apparent.One-chip computer 89C51P ₀Eight pins of mouth link to each other with the input pin of a slice XOR gate CD4030 with three liquid crystal driver CD4543 respectively, and concrete annexation is: single-chip microcomputer 89C51P ₀The P of mouth ₀₀, P ₀₁, P ₀₂, P ₀₃Be connected with individual position, input pin A, the B of hundred liquid crystal driver CD4543, C, D pin respectively, and P ₀₄, P ₀₅, P ₀₆, P ₀₇Then be connected with input pin A, B, C, the D of ten liquid crystal driver CD4543 respectively, so that the normal position measured, ten, hundred of showing.Kilobit of measurement result " 1 " and radix point are controlled by XOR gate CD4030.Three input pins of CD4030, promptly the 8th, 5 and 1 pin respectively with single-chip microcomputer 89C51P ₁The P of mouth ₁₀, P ₁₁, P ₁₂Connect, so that from i.e. the 3rd, 4,10 kilobit numerical value and the radix point that obtain the measurement results of three corresponding output terminals of CD4030, under the control signal effect, a slice CD4543 just can be with complete the showing of measured result like this.Control signal is by write signal WR and the address bus signal P of single-chip microcomputer 89C51 ₂The P of mouth ₂₆, P ₂₇Combine together, concrete annexation is: the P of single-chip microcomputer 89C51 ₂₆Pin connects toward linking to each other P with the input pin 1 of door 74HC08 ₂₇Link to each other with the input pin 5 of 74HC08, the write signal WR pin of single-chip microcomputer 89C51 then is connected with the input pin 5 of six reverser 74HC04,6 of output pins link to each other with the other input pin 2 and the pin 3 of door with above-mentioned two respectively, and two output pin 3 and 6 of pins with door are connected with the control pin 1 of three liquid crystal driver CD 4543 respectively.Other two reversers and the resistance R of 74HC04 ₁, R ₂, capacitor C ₀Form another multivibrator together, show the some drive signal for liquid crystal driver provides, circuit theory is with last identical.

With reference to Fig. 3, be provided with LCDs 4 on the top of housing 5; Power knob 3 is established in the left side; Test jack 1 is established in the bottom, tested inductance L _x2 insert on the test jack 1, circuit board by screw retention in housing 5.

Claims

1, a kind of intelligent inductance table is to be that core is mixed oscillatory circuit again and LCD is formed with the 89C51 single-chip microcomputer, it is characterized in that: tested inductance L _xForm a multivibrator with two reversers, two reversers can be taken from six reverser 74HC04, resistance R ₄An end and tested inductance L _xWith given capacitor C ₀An end link to each other resistance R ₄The other end be connected with (1) pin of six reverser 74HC04, (2) pin of six reversers links to each other with its (3) pin, simultaneously and tested inductance L _xThe other end link to each other (4) pin of six reversers and given capacitor C ₀The other end connect.This end is the output terminal of multivibrator simultaneously, the timer counter mouth T of the output terminal of multivibrator and one-chip computer 89C51 ₁Pin directly links to each other, one-chip computer 89C51P ₀Eight pins of mouth link to each other with the input pin of a slice XOR gate CD4030 with three liquid crystal driver CD4543 respectively, and concrete annexation is: single-chip microcomputer 89C51P ₀The P of mouth ₀₀, P ₀₁, P ₀₂, P ₀₃Be connected with individual position, input pin A, the B of hundred liquid crystal driver CD4543, C, D pin respectively, and P ₀₄, P ₀₅, P ₀₆, P ₀₇Then be connected with input pin A, B, C, the D of ten liquid crystal driver CD4543 respectively, three input pins of CD4030, promptly (8), (5) and (1) pin respectively with single-chip microcomputer 89C51P ₁The P of mouth ₁₀, P ₁₁, P ₁₂Connect, control signal is by write signal WR and the address bus signal P of single-chip microcomputer 89C51 ₂The P of mouth ₂₆, P ₂₇Combine the P of single-chip microcomputer 89C51 together ₂₆Pin connects input pin (1) past and door 74HC08, P ₂₇Link to each other with the input pin (5) of 74HC10, the write signal WR pin of single-chip microcomputer 89C51 then is connected with the input pin (5) of six reverser 74HC4, output pin (6) then links to each other with above-mentioned two other input pin (2) and pins (3) with door respectively, two output pin (3) and pins (6) with door then are connected other two reversers and the resistance R of 74HC04 respectively with the control pin (1) of three liquid crystal driver CD4543 ₁, R ₂Capacitor C ₀Form another multivibrator together, show the some drive signal, be provided with LCDs (4) on the top of housing (5) for liquid crystal driver provides; Power knob (3) is established in the left side; Test jack (1), tested inductance L are established in the bottom _x(2) insert on the test jack (1), circuit board by screw retention in housing (5).