CN2154519Y

CN2154519Y - Detector for electrochemistry micro-current

Info

Publication number: CN2154519Y
Application number: CN 93238447
Authority: CN
Inventors: 孙洪超
Original assignee: Individual
Current assignee: Individual
Priority date: 1993-04-06
Filing date: 1993-04-06
Publication date: 1994-01-26
Anticipated expiration: 2003-04-06

Abstract

The utility model relates to a detector which is composed of a sounding level indicating and driving integrated circuit, a triggering circuit, an integrated circuit of flicker music, a buzzer, an indicating luminous tube for electric current value, a display luminous tube for electric current flow direction, a detecting potentiometer, peripheral resistors and capacitors. The utility model utilizes the luminous tubes to indicate the value and the flow direction of electric current and music is accompanied, and therefore, the utility model is modern teaching demonstration experiment equipment of middle school electrochemistry of combination of teaching and recreation and a modern teaching appliance worthy of generalization.

Description

Detector for electrochemistry micro-current

The utility model relates to the little current detecting instrument of a kind of galvanochemistry that is used to impart knowledge to students.

In the galvanochemistry teaching, the experimental facilities operation inconvenience that textbook is arranged, the mathematics purpose phenomenon that experiment will reach is not obvious, as: the solution conductivity experiment, adopt the 220V AC power, bulb brightness is judged the power of this solution conductivity according to the observation, operation inconvenience, poor safety performance; The galvanic principles experiment adopts galvanometer to detect the generation of electric current, and the student is difficult for determining the electronics flow direction according to the yawing moment of galvanometer pointer; Utilize the detection of weak current that these experimental facilitiess produce fruit battery and galvanic corrosion powerless especially.Therefore, the experiment checkout equipment in the middle school chemistry experiment teaching is anxious to be solved.

The purpose of this utility model is to utilize electronic technology and emitting components, designs and a kind ofly qualitatively judges size of current, analog current direction, is applicable to whole lecture experiments of middle school galvanochemistry and student experimenting, and the detector that detects little electric current.

The little current detecting instrument of this galvanochemistry is indicated drive integrated circult, comparison trigger circuit, flicker music integrated circuit, hummer by sound level, size of current indication light emitting diode, current direction show light emitting diode, detect potentiometer and peripheral resistance capacitance formation, measured signal is taken out by detecting on the potentiometer, one the road delivers to and rings level indication drive integrated circult, and this circuit shows that output terminal links to each other with size of current indication light emitting diode respectively.Another road links to each other with trigger input signal anode, trigger input signal negative terminal links to each other with power supply by a resistor, trigger output termination flicker music integrated circuit trigger end, this circuit flicker indication output end connects current direction respectively and shows light emitting diode, and the music output terminal links to each other with hummer.The detector front end has four terminals, is to exchange AC, direct current DC positive supply 1.5V end and GND end respectively.

The principle of work of this detector is, when being added to after amplifying in the inner 5 step voltage comparers in sound level indication driving circuit, measured signal compares with reference voltage, and by the diode displaying comparative result, can judge the strong and weak degree of measured signal according to the luminotron number of lighting, when the comparative level of sound level indication driving circuit output is added on the trigger end of trigger, the trigger circuit output state flip, the work of flicker music integrated circuit, the light emitting diode that links to each other with its flicker output signal end circulates luminous, the simulation electronic flow direction, simultaneously, the hummer melody that strikes up, send dulect musical sound, acousto-optic and usefulness, vivid and interesting, intuitively, simple and direct, be suitable for detecting little electric current in whole lecture experiments of middle school galvanochemistry and the student experimenting, be a kind of stable performance, safe and reliable, detection sensitivity is high, and volume is little, detector low in energy consumption.It integrates intuitive and interest, is the model electrochemical teaching experimental equipment that teachers and students love.

Provide embodiment below in conjunction with accompanying drawing:

Fig. 1 is the little current detecting instrument electrical schematic diagram of galvanochemistry

Fig. 2 is a wiring diagram

Level indication driving circuit IC1 adopts the homemade sound equipment biserial 16 pin sound levels indication of D1405 drive integrated circult, this integrated circuit is by the Pyatyi voltage comparator, direct current amplifier and mu balanced circuit constitute, measured signal is imported by 3 pin, after amplifying, buffering is added to the inverting input of Pyatyi voltage comparator, compare with reference voltage then, and by indicating the light emitting diode D1～D6 of drive output to show size of current with level, according to the number of the light emitting diode of lighting, can judge the power of measured signal.Tested size of current is as follows with the corresponding relation of the light emitting diode number of lighting:

Tested electric current (μ A) 0.05 0.10 0.15 0.20 0.30

Light light emitting diode number 12346

Trigger circuit IC2 adopts homemade four to compare LM339, get 1/4th and make trigger, the 50mV reference voltage adds to the inverting input of comparer, and measured signal is gone up by test side potentiometer R1 and taken out, and delivers to 3 pin of IC1 and the in-phase input end of IC2 respectively, when static, be output as low-voltage, triggerless voltage is as input signal V+〉during V-, the comparer upset, the output triggering level.

Flicker integrated circuit (IC) 3 adopts the homemade music flicker of KD-07 integrated circuit.After trigger end TR adds trigger voltage, circuit working, 7 LED light emitting diodes that its flicker output terminal D7～D13 connects respectively circulate luminous, and so as to the simulation electronic flow direction, simultaneously, the hummer Y that links to each other with its sound equipment output terminal begins to gather melody.

This little current detecting instrument test lead be divided into AC, DC ,+four terminals of 1.5V, GND.Select corresponding test lead for use according to different detected objects.

The utility model applicating example:

One, electric conductivity experiment: will+1.5 and DC(be used to test direct current signal) two test clips press from both sides graphite electrode respectively, and insert in the distilled water simultaneously, adjust SA(R1), make luminotron just light one, insert liquid to be measured (fused mass) then successively, intuitively determine measured object electric conductivity power according to the number that luminotron is lighted, also can compare different material electric conductivity power under the same conditions.

Two, galvanic principles and electrochemical corrosion experimental:

1, galvanic principles: with " DC " test clamping connection copper zinc original battery positive pole, " GND " test clamping connection copper zinc original battery negative pole, luminotron is lighted, and the direction that the mobile luminous simulation electronic of D7-D13 flows is with musical sound.With the exchange of two test clips, circuit is not worked.Use the high sensitivity of this instrument, also can detect the melon and fruit battery, the weak current that the flowerpot battery is produced.

2, the metal activity relatively: two kinds of clean metal to be compared are used as electrode insert in the suitable electrolyte solution, be connected on " DC " and " GND " two test clips on two electrodes respectively, LED lighted, then " GND " electrode of being connect is more active.

3, oxygen uptake corrosion: be placed on the glass plate with the copper wire electrode with iron wire and (do not contact), " DC " test clamping connection copper wire, " GND " test clamping connection iron wire, regulate SA(R1), make the LED luminotron light one, near positive pole, remove a small amount of MnO2 powder then, drip 1-2 and drip hydrogen peroxide, as seen the number of elements lighted of LED luminotron increases, and increases to show electric current, and corrosion is quickened.

4, anti-electrochemical corrosion experimental: in the primary element loop that iron, carbon electrode are formed, serial connection one joint dry cell, negative pole connects the ferroelectric utmost point, and visible former luminous LED extinguishes, and proves that direction of current changes, and iron is protected.

Three, " AC " test clip of this detector cooperates " GND " test clip also to can be used for detecting faint AC signal.The detecting device that also can be used for photoelectric effect experiment.

Claims

1, the little current detecting instrument of galvanochemistry, it is characterized in that by sound level indication drive integrated circult IC1, trigger circuit IC2, flicker music integrated circuit IC3, hummer Y, size of current indication luminotron, current direction shows luminotron, detecting potentiometer and peripheral resistance capacitance constitutes, measured signal is taken out by detecting on the potentiometer, one the road delivers to sound level indication drive integrated circult, this circuit shows that output terminal links to each other with size of current indication light emitting diode respectively, another road links to each other with trigger input signal anode, trigger input signal negative terminal links to each other with power supply by a resistor, trigger output termination flicker music integrated circuit trigger end, this circuit flicker indication output end connects current direction respectively and shows light emitting diode, and the music output terminal links to each other with hummer, the detector front end has four terminals, be respectively to exchange the AC end, direct current DC end, positive power source terminal and ground (GND) end.

2, the little electric current of galvanochemistry as claimed in claim 1 is examined then instrument, it is characterized in that IC1 selects for use D1405, IC2 to select for use LM339, IC3 to select KD-07 for use, the positive power source terminal of detector front end is 1.5V, size of current indication luminous component output terminal most significant digit two light emitting diodes of having connected.