CN1064944A

CN1064944A - Electric circuit for photoelectric color-imeter

Info

Publication number: CN1064944A
Application number: CN 92106884
Authority: CN
Inventors: 金则明
Original assignee: Individual
Current assignee: Individual
Priority date: 1992-04-10
Filing date: 1992-04-10
Publication date: 1992-09-30

Abstract

The present invention relates to a kind of electric circuit for photoelectric color-imeter according to photoelectric effect and Beer law design, it adopt a four-operational amplifier LM324 to finish to amplify in the circuit and conversion and alternating current through magnetic saturation AC voltage-stabilizing reducing transformer (2) again through two-way voltage multiplying rectifier filtering circuit (3), supply with two integrated package of pressure-stabilizing (4) (5) respectively.That this circuit has is cheap, integrated level is high, technical indicator is high, can carry out update to 581-G type photolometer easily.

Description

Electric circuit for photoelectric color-imeter

The present invention relates to a kind of electric circuit for photoelectric color-imeter according to photoelectric effect and Beer law design.Photolometer is a kind of instrument that is used for measuring colored solution concentration.

In the popular photolometer of existing direct-reading, the 581-G type is simple in structure with it, cheap advantage is very big in China's basis health unit owning amount, because the detection index system of this machine adopts the moving-coil string galvanometer, therefore it is fragile to exist performance, and sensitivity is low, linear, poor stability, major defects such as the photoelectric cell life-span is short, the many provinces and cities of China health organization has been assigned the notice of progressively eliminating.The product that replaces the 851-G type has DG211, DG811 type photolometer, and 721 type spectrophotometers, but all price is higher, can not AC/DC, be difficult to promote the popularization use.

Task of the present invention provides that a kind of circuit is simple, technical indicator is higher, cheap, integrated level is high, easy to operate, adapt to the wide popular electric circuit for photoelectric color-imeter of voltage range.

Task of the present invention is finished as follows: finish in the circuit with an integrated height, cheap four-operational amplifier LM324 and amplify and conversion work, 220 volts of alternating voltages are by magnetic saturation AC voltage-stabilizing reducing transformer, be transformed into DC voltage through two-way voltage multiplying rectifier filtering circuit again, supply with the electricity consumption of two-way integrated package of pressure-stabilizing, one the tunnel for operational amplification circuit, one the tunnel for the illuminator circuit, in the four-operational amplifier LM324 integrated package, one as bi-directional power change-over circuit, one as the photocurrent amplifying circuit, one as electronic switching circuit.

Photolometer adopts this circuit cheap, and the integrated level height, sees following table for details at the technical indicator height:

Annotate: 1,721 type spectrophotometers are middle-grade machine.

2, in the table 1,721 type pointer deviations belong to national standard, and this circuit pointer deviation is according to the standard code practical measurement.

3, in the table 2, data are that two machine actual detected draw.

This circuit can be assembled on the printed circuit board (PCB) than small size, connect 50 microamperes of direct-reading ammeters and become the tintmeter circuit unit, this assembly also can be used to replace 581-G type photolometer moving-coil string galvanometer system, unit to existing 581-G type photolometer, just can undergo technological transformation with a spot of fund, play the effect of upgrading.

Below in conjunction with accompanying drawing optimum implementation of the present invention is described in detail.

Fig. 1 is optimum implementation circuit theory diagrams of the present invention, and four-operational amplifier is an integrated package among the figure, and model is LM324.

Fig. 2 is an optimum implementation course of work block scheme of the present invention.

Fig. 3 is optimum implementation circuit printing plate figure of the present invention.

With reference to Fig. 1, Fig. 2,220 volts of alternating voltages are through attaching plug [1], become 6 volts of stable alternating voltages through magnetic saturation AC voltage-stabilizing reducing transformer [2] again, be divided into two-way through two-way voltage multiplying rectifier filtering circuit [3] again, supply with 8 volts of integrated package of pressure-stabilizing [4] and 6 volts of integrated package of pressure-stabilizing [5] respectively, bi-directional power change-over circuit [6] is connected into follower, W among the figure ₁Be bi-directional voltage balance adjustment potentiometer, this circuit has very low output resistance and profound negative feedback, this guarantees that just back level photocurrent amplifying circuit [7] steady operation is needed, photocurrent amplifying circuit [7] is connected into scale operation and amplifies, enlargement factor is adjustable continuously, PC is a selenium cell among the figure, because photoelectric cell only is operated in when hanging down loaded impedance, the linear of photocurrent and illuminance just can be best, therefore it directly is connected with end of oppisite phase with the operational amplifier in-phase end, utilizing this two terminal potential is zero characteristics, help obtaining good linear, promote photocurrent indicating circuit [10], between bi-directional power change-over circuit [6] and photocurrent amplifying circuit [7], be connected to acyclic homologically trioial economize on electricity road [8], between photocurrent amplifying circuit [7] and photocurrent indicating circuit [10], be connected to full scale regulating circuit [9], wherein W ₃Be full scale coarse adjustment, W ₄Be the full scale fine tuning, work in coordination and regulate the ammeter full scale that promptly 100%, 6 volt of regulator block [5] joins with electronic switching circuit [11].Electronic switch [11] is connected into degree of depth positive-feedback circuit, during start because C ₇Effect to make in-phase end be zero potential, output terminal is a negative potential, and through R ₁₂Control oneself BG ₂End, relay J is failure to actuate, and illuminator [12] does not work, when pressing logical K switch once ₂, C ₈On negative voltage be added to end of oppisite phase, positive potential appears in output terminal, and through R ₁₂Feedback is controlled oneself, BG ₂Conducting, the J adhesive, illuminator [12] is bright; Click K again ₂, C ₈Through R ₁₃The positive voltage that obtains is added to end of oppisite phase, and output terminal is a negative potential, and through R ₁₂Control oneself BG ₂End, the J outage, illuminator [12] extinguishes, finished the switching function of illuminator [12], the light that illuminator [12] sends shines on the colorimetric solution through light-filtering glass, and the illumination that sees through solution is to photoelectric cell, and illuminator indication illuminating circuit [13] is connected between electronic switching circuit [11] and the illuminator [12], [14] be power supply indication illuminating circuit, [15] are power switches.For the photolometer of circuit of the present invention can use direct supply, the present invention's design has 9 volts of direct current jacks [16].[17] be dc protection circuit, to prevent that the direct supply both positive and negative polarity from connecing electric current anti-and that cause because of the direct supply brownout and pouring in down a chimney.Start shooting for the photolometer that makes circuit of the present invention at every turn and to play a bent music, and also having one in the four-operational amplifier does not use, the present invention designs 3 volts of reduction voltage circuits [18] and music horn circuit [19], because the music-integrating block operating voltage only needs 3 volts, and working current is bigger, so 3 volts of reduction voltage circuits [18] are connected into follower, 4 volts of voltages of output terminal are added to transistor BG ₁Base stage obtains 3.3 volts of voltages for music horn circuit [19] at its emitter.So far, this circuit of function of four-operational amplifier LM324 exhausts.

Claims

1, a kind of electric circuit for photoelectric color-imeter, its feature one is to finish in the circuit with a four-operational amplifier LM324 to amplify and conversion work, wherein one as bi-directional power change-over circuit [6], one as photocurrent amplifying circuit [7], one as electronic switching circuit [11], two is that 220 volts of alternating voltages are through magnetic saturation AC voltage-stabilizing reducing transformer [2], become DC voltage through two-way voltage multiplying rectifier filtering circuit [3] again, supply with two-way integrated package of pressure-stabilizing [4], [5], one the tunnel for operational amplification circuit [6], [7], and one the tunnel for illuminator circuit [11], [12].

2,, it is characterized in that design has 9 volts of direct current jacks [16] by the described electric circuit for photoelectric color-imeter of claim 1.

3,, it is characterized in that design has dc protection circuit [17] by the described electric circuit for photoelectric color-imeter of claim 2.

4,, it is characterized in that design has 3 volts of reduction voltage circuits [18] and music horn circuit [19] by claim 1 or 2 or 3 described electric circuit for photoelectric color-imeter.