CN2507094Y

CN2507094Y - Multi-purpose electric experiment box

Info

Publication number: CN2507094Y
Application number: CN 01222097
Authority: CN
Inventors: 骆乃光
Original assignee: Individual
Current assignee: Individual
Priority date: 2001-11-11
Filing date: 2001-11-11
Publication date: 2002-08-21
Anticipated expiration: 2011-11-11

Abstract

A multifunctional electricity experiment box for higher educational institutions relates to electricity experiment, comprising two slide wire resistors respectively cascade connected and parallel connected in an overall circuit for regulating voltage and current in an experiment circuit and displaying voltage and current through a standard voltmeter and a current meter. An external equipment can be power supplied in positive and negative directions through converting a switch, and can be cascade connected and parallel connected through a standard electric resistance box. The multifunctional electricity experiment box can accomplish more than ten experiments, in order to resolve the questions that at present, equipments are scattered during doing experiments, and temporary connection is needed.

Description

Multipurpose electricity test box

Technical field

The utility model relates to a kind of device that college student carries out Experiments of Electricity, especially for electromagnetics, and some experiments of calorifics and galvanochemistry aspect.

Background technology

A few days ago in colleges and universities and the relevant experiment of electricity, aspect physics as electric meter refitting, the sensitive galvanometer characteristic research, volt-ampere of characteristic diode research, and mechanical equivalent of heat experiment and some other experiments are aspect chemical, image current titration, electroanalysis etc., each colleges and universities all uses the electrotechnical apparatus that disperses, instrument and meter patch, and also nonidentical of the used equipment of each colleges and universities and instrument.These disperse the preliminary work of instrument to experiment, the arrangement after the experiment, and the instrument storage has inconvenience more.

Technology contents

The utility model adopts a kind of simple device, can finish the experiment of tens electricity aspects that relate to.

The utility model is connected in the entire circuit with rheostat after adopting the power supply input.Be connected in parallel on both ends of power with rheostat in addition again, shown with voltage table and reometer with that.This step just can be satisfied some experiment needs; Therefore just can draw with two terminals.Some requirement of experiment electric current had both needed forward, negate again to, need to add a dpdt double-pole double-throw (DPDT) reverser for this reason, can have binding post to draw again, to satisfy the part requirement of experiment.On above basis, increase a standard resistance box, can be used for the experiment of ammeter electric meter refitting.If increase a standard resistance box and a little resistance measuring resistance again, can be used for the sensitive galvanometer characteristic research.The precision of voltage table, reometer, measuring resistance and resistance box is depended in the accuracy of device.

Adopt present design, can dress up a multi-usage experimental box, just can experimentize as long as plug low-voltage dc power supply with minimum device.Also the conversion portion design that can become low-voltage dc power supply to civil power makes that plugging civil power can test in electricity test box.

Description of drawings

Fig. 1 is the specific embodiment of the utility model circuit diagram.

Fig. 2 is the circuit diagram after the minimizing part of devices.

Fig. 3 is the circuit diagram after increasing part of devices on Fig. 1 circuit base.

Fig. 4 is the circuit diagram that civil power converts D.C. regulated power supply to

In the drawings, 1. low-voltage DC supply socket 2. power meters 3. multirange standard voltmeters 4. multirange standard amperemeters 5. slide wire resistors 6. slide wire resistors 7. standard resistance boxs 8. standard resistance boxs 9. measuring resistances 10. single-pole double-throw switch (SPDT) K ₁Contact e is arranged, d 11. single-pole triple-throw (SPTT) K switch ₂12. single-pole triple-throw (SPTT) K switch ₃13. double-pole two is thrown reversing switch K ₄14. single-pole triple-throw (SPTT) K switch ₅15. button 16. 3 winding terminal: A, B, C, D, E, F and separately and binding post G and M 17. three terminal regulator LM317 18. three terminal regulator LM317 19. resistance 20. resistance 21. rectifier bridges pile 22. mains electricity input end, 23. frequency power transformers, 24. resistance, 25. adjustable resistances

Embodiment

Fig. 1 is an embodiment of the present utility model.

In Fig. 1, after low-voltage dc power supply inserts socket 1, can change electric current in the circuit and the voltage on the object being measured two ends by slide wire resistor 5 and 6, and show that by voltage table 3 and reometer 4 reversing switch 13 can give object being measured between binding post C and D with forward, reverse two kinds of electric currents.Switch 14 can make resistance box 7 insert or disconnecting circuit.It can finish following experiment:

Meter resistance is measured:

Fig. 1 is pressed in the position of the switch, ammeter to be measured meets binding post C, D, and cut-off switch 14 is regulated and slided resistor 6, make ammeter to be measured to full scale, write down the value of reometer 4, switch 14 points to L then, regulates slide wire resistor 5 and 6, and adjusting resistance box 7, the indicating value that reaches reometer 4 is constant, and the displayed value that makes tested ammeter is half of initial value, and then the indicating value of resistance box 7 is tested meter resistance value.More than adopt the half value method to measure meter resistance.Also can be after connecting tested ammeter between C, D, switch 14 points to m, writes down the value of reometer 4, removes tested ammeter, and switch 14 points to 1, regulates resistance box 7, makes reometer 4 indicating values constant, and the value of resistance box 7 is exactly the internal resistance value of ammeter.More than adopt the total head method to measure meter resistance.

Electric meter refitting becomes reometer:

Regulate rheochord 6 and make reometer 4 that a round values be arranged, regulate resistance box 7 and make the ammeter full scale that will reequip also show this value, then resistance value on the resistance box 7 and repacking make needs shunt resistance value in parallel.

The electric meter refitting voltage table:

In Fig. 1, switch 12 points to h, and switch 14 points to m, the ammeter one termination binding post C that needs are changed, another termination binding post M, because M and m communicate,, regulate rheochord 6 so tested table and resistance box 7 are connected in the circuit, make voltage table 3 that a round values be arranged, regulate resistance box 7, make the modified table full scale, then the indicating value of resistance box 7 is modified table and reaches this range and need series impedance.

Diode and the research of change resistance volt-ampere characteristic:

Switch points to m, the indirect diode of binding post C and D, switch 13 points to I (j), as this moment diode be forward bias, then switch 12 points to f, standardsizing rheostat 5 and 6, recording voltage, current relationship; Again switch 13 is pointed to j (I) switch 12 and point to h, standardsizing rheostat 5 and 6, recording voltage, current relationship.

Substitute diode with miniature bulb and can become the research of resistance volt-ampere characteristic.

Fig. 2 is another embodiment, and the difference of it and Fig. 1 embodiment only is to have reduced a reversing switch K ₄And K switch ₅With two binding post C and D, so Fig. 1 embodiment also can do down the example experiment:

The mechanical equivalent of heat is measured:

Switch 11 sensing C make in power meter 2 places in circuit in Fig. 2, and switch 10 points to e makes rheostat 6 cut out circuit, and binding post A and B indirect resistance silk are put into electric weight thermal capacitance device, by the quality and the intensification of water, voltage table, reometer, the power meter indicated value can be measured the mechanical equivalent of heat.

The mensuration of specific heat of liquid:

Switch points to identically when measuring with the mechanical equivalent of heat, and binding post A and the B two ends two groups of resistance wires that resistance is identical of connecting are put into two electric weight thermal capacitance devices respectively, put distilled water in one of them container, and another is put testing liquid and can be experimentized.

Voltage table is proofreaied and correct:

In Fig. 2, binding post A and B connect calibrated meter, and switch 11 points to a, and switch 10 points to d, and switch 12 points to h, regulate slide wire resistance 5 and 6 and make calibrated meter arrive full scale, the absolute error when difference of standard voltmeter and calibrated meter is full scale.

Reometer is proofreaied and correct:

In Fig. 2, calibrated meter is connected with binding post A and B, and switch 12 points to f, regulates slide wire resistance 5 and 6, makes calibrated meter absolute error when the difference of full scale and standard amperemeters is full scale.

Aspect galvanochemistry:

Amperometric titration:

Fig. 2 binding post A connects saturated calomel electroplax, and binding post B connects platinum electrode just can carry out amperometric titration.K ₁To b, K when finishing ₁Adopt one logical one to break.

The control cathode potential electrolysis is analyzed;

Switch 12 points to g, regulates 6, makes V to the needs current potential, and binding post G connects contrast electrode.

A connects platinum guaze, and B connects the spirality platinum filament just.

Electroanalysis:

Fig. 2 can be used for electroanalysis, and binding post A and B connect electroplax just.

Fig. 3 is another embodiment, and it is to increase a standard resistance box 8 and a little resistance measuring resistance 9 on Fig. 1 embodiment basis, adds binding post E and F again, can be used for the sensitive galvanometer characteristic research.

If Ig is the sensitive galvanometer current constant, Rg is the sensitive galvanometer internal resistance

Switch 14 points to O in Fig. 3, and voltage table points to f or h, and sensitive galvanometer meets binding post E and F.Make resistance box 7 and resistance box 8 resistances resistance during design much larger than measuring resistance 9.

The resistance of the accurate resistance 9 of bidding is Ro, and the resistance of resistance box 7 is R ₁, the resistance of resistance box 8 is R ₂, then have:

Ig＝U _Ro/(R ₂+Rg)

U _Ro＝RoU/(R ₁+Ro)

So

Ig＝RoU/(R ₁+Ro)(R ₂+Rg)

(wherein U is the voltage table reading, U _RoPressure drop for measuring resistance 9)

By changing slide wire resistance 6 and resistance box 8, the magnitude of voltage of the voltage table 3 that maintains the standard and the indicating value of resistance box 7 are constant, and de-connecting cube journey just can be in the hope of the value of Ig, Rg.

Fig. 4 is the circuit diagram that civil power is converted to low-voltage dc power supply.

After 22 inputs of civil power process socket and step-down transformer 23 step-downs, again by rectifier bridge heap 21 and capacitor C ₁Filtering becomes direct current; Three terminal regulator 17 and 18, resistance 19,20,24 and adjustable resistance 25 are formed the secondary mu balanced circuit.Resistance 20 should be greater than 2 with the resistance value ratio of resistance 19.Regulate the size of resistance 25 resistances, can change the voltage height that outputs to socket 1.Resistance 24 desirable 240 ohm, at this moment output voltage is calculated as follows:

[(resistance 25 resistances/resistance 24 resistances)+1] * 1.25V

Capacitor C ₂, C ₃Desirable 0.33uF, capacitor C ₄In order to improve the ripple of output.

Claims

1. multipurpose electricity test box, after the low-voltage dc power supply input, size by a slide wire resistance of connecting (5) Control current with circuit, and show with standard amperemeters, slide wire resistance (6) the control experiment part voltage height that another is connected in parallel in the circuit also has standard voltmeter (3) to carry out indicating value and shows; Circuit by switch (13) be docked at binding post (C) and (D) on experimental facilities carry out positive and negative two directions power supply, standard resistance box (7) can be docked at the experimental facilities that binding post (C) reaches (D) by switch (14) and carry out serial or parallel connection.

2. multipurpose electricity test box according to claim 1, its working power can be that civil power forms through converting low-voltage dc power supply to, and the civil power conversion partly can be contained in the multipurpose electricity test box casing.

3. multipurpose electricity test box according to claim 1 and 2 can save switch (13) and (14), resistance box (7), by binding post (A) and (B) connects that experimental facilities experimentizes.

4. multipurpose electricity test box according to claim 1 and 2 can also have measuring resistance (9), and resistance box (8) and button (15) are by binding post (E) and (F) sensitive galvanometer is carried out characteristic research.