CN2160342Y

CN2160342Y - Measurer for biological impedance

Info

Publication number: CN2160342Y
Application number: CN 93228321
Authority: CN
Inventors: 高维纬; 王明顺; 付永久; 孙阳; 陈昕; 尚超
Original assignee: Shenyang Sport University
Current assignee: Shenyang Sport University
Priority date: 1993-05-28
Filing date: 1993-05-28
Publication date: 1994-04-06
Anticipated expiration: 2003-05-28

Abstract

The utility model provides a measurer for biological impedance, which is the same as foreign existing measurers for biological impedance. The utility model, as well as the foreign existing measurers, is composed of a sine-wave output circuit, a testing circuit, an A/D converter, a single chip machine, a memorizer, a display, etc. The utility model is characterized in that the signal source of the utility model adopts a digital oscillating source, and namely, the sine-wave output circuit and the testing circuit are different from the prior art. Compared with the prior art, the signal source of the utility model adopts the digital oscillating source, and thus the utility model has the advantages of stable signal frequency, high measuring precision, etc. The utility model is applied to biomedical researches to provide necessary data of the impedance in organism for the biomedical researches.

Description

Measurer for biological impedance

This utility model belongs to a kind of device that is used for the test organism impedance.

Bio-impedance has been effectively applied to require the measuring technique of bio-impedance in practice in the biomedical research as a kind of biological indicator, must be that measuring process is safe and reliable, and measurement result is accurate, just can be promoted widely.Domestic still do not have enterprise so far and produce this quasi-instrument.Though similar products are abroad arranged, it measures the simulation oscillating circuit composition that the required elements such as instrument source employing RLC of bio-impedance are formed, and makes it have certain problem at aspects such as frequency accuracies, and its result directly influences the certainty of measurement and the accuracy of bio-impedance.

The purpose of this utility model provides a kind of bio-impedance tester, and its signal source adopts digital oscillation source, so its certainty of measurement height.

The purpose of this utility model is achieved in that it is the same with external existing bio-impedance tester, all form by sinusoidal wave output circuit, test circuit, A/D, single-chip microcomputer, memorizer and display etc., feature of the present utility model is: its signal source adopts digital oscillation source, be that sinusoidal wave output circuit is different with prior art with test circuit, introduce the composition and the principle of these two circuit below respectively.

1, sinusoidal wave output circuit

It is made up of digital signal oscillation source, digital divider circuit, waveform generation and filter circuit and output driving circuit;

1.1, the digital signal oscillation source

Form digital signal oscillation source (being typical circuit) by crystal oscillator JT1, two resistance and two electric capacity and inverter ic 13A, its output termination inverter ic 13:B, with signal carry out anti-phase after, send into the input of frequency dividing circuit, be the CLK end of IC14, produce the very high digit pulse of frequency this moment;

1.2, frequency dividing circuit is made up of binary counter IC14 and decade computer IC15, signal is delivered to the CLK end of IC15 again behind the two divided-frequency of IC14, ten minutes frequency through IC15, the frequency of pulse is lowered, send into the input of Waveform generating circuit, be i.e. the CLK of IC16 end;

1.3, the composition of Waveform generating circuit

Can preset N exponent counter IC16's

End meets R18, R17, R16 and R15 respectively, connects with R14 in back in parallel, and it becomes digital pulse signal into the staircase waveform of near sinusoidal ripple, send filter circuit;

1.4, filter circuit forms (being typical circuit) by amplifier IC17 and two capacitor C 10, C11, it carries out filtering to staircase waveform, is sine wave of C10 place output at its outfan, send output driving circuit;

1.5, output driving circuit forms inverting amplifier (being typical circuit) by amplifier IC11 and three resistance and a potentiometer.The sinusoidal signal that the amplification filtering circuit comes, and drive output, finish sinusoidal signal voltage V0 output.

2, test circuit

It is made up of variable connector, difference amplification, rectification circuit and filter circuit;

2.1, variable connector served as by analog multichannel switch IC5, its A, B end input signal is from the specific outfan of single-chip microcomputer, Vo voltage is introduced the X0 of IC5 through R16, and directly introduces Y1, meets X0, X1, Y1 and the Y2 of IC5 respectively with organism electrodes in

contact

1,2,3,4;

2.2, differential amplifier circuit forms (being typical circuit) by amplifier IC6 and four resistance, receives the analog sinus signals of X, the Y output among the IC5, through its amplification, send rectification circuit;

2.3, rectification circuit forms (being typical circuit) by amplifier IC12 and D1, D2, R4 and potentiometer W1, its output ripple direct current signal send filter circuit;

2.4, filter circuit is made up of R3 and C3, and the pulsating direct current signal is become stable direct current signal, send A/D, single-chip microcomputer to go to handle.

This utility model compared with prior art because its signal source adopts digital oscillation source, so it has, and signal frequency is stable, the certainty of measurement advantages of higher.

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

Fig. 1 is an electric theory diagram of the present utility model.

Fig. 2 is the theory diagram of sinusoidal wave output circuit.

Fig. 3 is the theory diagram of test output circuit.

Fig. 4 is the electrical schematic diagram of sinusoidal wave output circuit.

Fig. 5 is the electrical schematic diagram of test output circuit.

Referring to Fig. 1, it is the same with existing bio-impedance tester, all form by sinusoidal wave output circuit, test circuit, A/D, single-chip microcomputer, memorizer and display etc., feature of the present utility model is: its signal source adopts digital oscillation source, be that sinusoidal wave output circuit is different with prior art with test circuit, introduce the composition and the principle of these two circuit below respectively.

1, sinusoidal wave output circuit (referring to Fig. 2):

1.1, digital signal oscillation source (referring to Fig. 4):

Form digital signal oscillation source (being typical circuit) by crystal oscillator JT1, two resistance R 19, R20 and two capacitor C 13, C14 and inverter ic 13:A4069, its output termination inverter ic 13:B, with signal carry out anti-phase after, send into the input of frequency dividing circuit, be the CLK end of IC14, produce the very high digit pulse of frequency this moment;

1.2, frequency dividing circuit is made up of binary counter IC14 74LS393 and decade computer IC15 4017, signal is behind the two divided-frequency of IC14, deliver to the CLK end of IC14 again, ten minutes frequency through IC15, the frequency of pulse is lowered, send into the input of Waveform generating circuit, i.e. the CLK of IC16 end;

1.3, the composition of Waveform generating circuit

Can preset N exponent counter IC16's 4018

1.5, output driving circuit forms inverting amplifier (being typical circuit) by amplifier IC11 and three resistance R 11, R10, R8 and potentiometer W6.The sinusoidal signal that the amplification filtering circuit comes, and drive output, finish sinusoidal signal voltage V0 output.

2, test circuit (referring to Fig. 3):

2.1, referring to Fig. 5, variable connector is served as by analog multichannel switch IC5 4052, its A, B end input signal is from the specific outfan of single-chip microcomputer 8031, Vo voltage is introduced the X0 of IC5 through R16, and directly introduces Y1, meets Xo, X1, Y1 and the Y2 of IC5 respectively with organism electrodes in

contact

1,2,3,4;

2.2, differential amplifier circuit forms (being typical circuit) by amplifier IC6 and four resistance R 10, R9, R22, R23, receives the analog sinus signals of X, the Y output among the IC5, through its amplification, send rectification circuit;

2.3, rectification circuit forms (being typical circuit) by amplifier IC12 and D1, D2, R4 and resistor W1, its output ripple direct current signal send filter circuit;

Claims

1, a kind of bio-impedance tester, it is made up of A/D converter, single-chip microcomputer and memorizer, display etc., it is characterized in that: further comprising sinusoidal wave output circuit and test circuit,

(1), sinusoidal wave output circuit

(1.1), digital signal oscillation source

Form the digital signal oscillation source by crystal oscillator JT1, two resistance and two electric capacity and inverter ic 13A, its output termination inverter ic 13: B, with signal carry out anti-phase after, send into the input of frequency dividing circuit, i.e. the CLK of IC14 end;

(1.2), frequency dividing circuit is made up of binary counter IC14 and decade computer IC15, signal is delivered to the CLK end of IC15 again behind the two divided-frequency of IC14, through the ten minutes of IC15 frequently, send into the input of Waveform generating circuit, i.e. the CLK of IC16 end;

(1.3), the composition of Waveform generating circuit

Q1, Q2, Q3, the Q4 end that can preset N exponent counter IC16 meets R18, R17, R16 and R15 respectively, connects with R14 in back in parallel, and it becomes digital pulse signal into the staircase waveform of near sinusoidal ripple, send filter circuit;

(1.4), filter circuit is made up of amplifier IC17 and two capacitor C 10, C11, is sine wave of C10 place output at its outfan, send output driving circuit;

(1.5), output driving circuit forms inverting amplifier by amplifier IC11 and three resistance and a potentiometer, drives output sinusoidal signal voltage V0;

(2), test circuit

(2.1), variable connector is served as by analog multichannel switch IC5, its A, B end input signal is from the specific outfan of single-chip microcomputer, Vo voltage is introduced the X0 of IC5 through R16, and directly introduces Y1, meets Xo, X1, Y1 and the Y2 of IC5 respectively with organism electrodes in contact 1,2,3,4;

(2.2), differential amplifier circuit is made up of amplifier IC6 and four resistance, receives the analog sinus signals of X, the Y output among the IC5, through its amplification, send rectification circuit;

(2.3), rectification circuit is made up of amplifier IC12 and D1, D2, R4 and resistor W1, its output ripple direct current signal send filter circuit;

(2.4), filter circuit is made up of R3 and C3, and the pulsating direct current signal is become stable direct current signal, send A/D to go to handle.

2, bio-impedance tester according to claim 1 is characterized in that:

IC13 selects 4069

IC14 selects 74LS393

IC15 selects 4017

IC16 selects 4018

Single-chip microcomputer selects 8031.