Acousto-optic demonstration heat transfer device

Abstract

The sound and light demonstration heat transfer device consists of a heat conductor, a thermistor, an identification and drive circuit, an LED lamp group, and a voice control circuit; the thermistors of each basic unit circuit are successively connected to the heat conductor. As heat is transferred, heat is transferred from the end with a higher temperature to the end with a lower temperature. The LED lamp groups of different colors are successively lit, and numbers are sounded in a corresponding order. If the other end of the heat conductor is heated, the LED lamp group will be lit in reverse order, and the number sounding order will also be reversed. The sound and light display is vivid, specific, intuitive, eye-catching, novel and practical. The circuit is simple, the cost is low, it is stable and reliable. After the power supply is disconnected and the heat conductor is cooled with water, the experiment can be carried out again in a short time.

Description

Technical Field:

[0001] The present invention relates to the field of electronic control, and particularly to an acoustic-optical demonstration heat transfer device. Background Art:

[0002] In the existing sixth lesson of the second unit in the fifth grade textbook of primary school science, "How Heat is Transferred", in the experiment, matches are pasted with candles or vaseline. The dropping of the matches is affected by the amount of vaseline pasted and the firmness of the paste. Using an alcohol lamp for heating to conduct a heat transfer experiment is simple and convenient. However, when conducting a demonstration experiment, if the matches drop, since the matches are small and the students in the back row are far away, it is difficult to see clearly, and the demonstration effect is poor. Summary of the Invention:

[0003] The purpose of the present invention is to provide an electronic experimental demonstration device for heat transfer to solve the problem that in the heat transfer experiment using an alcohol lamp to heat a metal, matches are pasted on the heat conductor at intervals with candles or vaseline, and when using an alcohol lamp to heat the metal for the heat transfer experiment, the matches drop, the matches are small, and the demonstration effect is poor. As heat is transferred, heat is transferred from the end with a higher temperature to the end with a lower temperature. Thermistors are connected at intervals on the heat conductor. Utilizing the temperature characteristics of the thermistors, after the heat conductor is heated, through circuit recognition, LED lamp groups of different colors in each basic unit circuit are sequentially lit. If heating is performed at the other end of the heat conductor, the LED lamp groups are sequentially lit in the reverse direction, and at the same time, digital voice is emitted in the corresponding order. After the optocoupler output terminal is turned on and then off, it is convenient for subsequent control; the novel demonstration in a transformed form brings another scientific experience to students, can further stimulate students' curiosity and thirst for knowledge, is vivid, specific, intuitive and eye-catching, and has a good demonstration effect.

[0004] Acousto-optic demonstration heat transfer device, characterized in that it consists of a heat conductor 1, a thermistor 2, an identification drive circuit 3, an LED lamp group 4, and a voice control circuit 5; the positive pole of the power supply is connected to the heat conductor 1, the heat conductor 1 is connected to the sampling terminal of the precision voltage reference integrated circuit KA1 of the thermistor 2RT1 to the identification drive circuit 3, the sampling terminal of the precision voltage reference integrated circuit KA1 of the identification drive circuit 3 is connected to the resistor R7 to the negative pole of the power supply, the ground terminal of the precision voltage reference integrated circuit KA1 of the identification drive circuit 3 is connected to the negative pole of the power supply, the control terminal of the precision voltage reference integrated circuit KA1 of the identification drive circuit 3 is connected to the negative terminal of the input of the resistor R6 and the optocoupler PC2, the positive terminal of the input of the optocoupler PC2 is connected to the positive pole of the power supply, the positive terminal of the output of the optocoupler PC2 is connected to the positive pole of the power supply, the negative terminal of the output of the optocoupler PC2 of the identification drive circuit 3 is connected to the resistor R5, the LED lamp group 4TD1, to the negative pole of the power supply, the negative terminal of the output of the optocoupler PC2 of the identification drive circuit 3 is connected to the resistor R2 of the voice control circuit 5 and connected to the base of the triode Q1, the emitter of the triode Q1 is connected to the negative pole of the power supply, the collector of the triode Q1 is connected to the positive pole of the power supply through the resistor R1 and the input of the optocoupler PC1, the output of the optocoupler PC1 is connected to the two contact points at both ends of the "corresponding number" such as the button of the number "1" of the electronic voice calculator, and pay attention to the high and low ends of the signals at both contact points of the corresponding number button when connecting; the negative terminal of the output of the optocoupler PC2 of the identification drive circuit 3 is connected to the resistor R4 of the voice control circuit 5 and connected to the base of the triode Q2, the base of the triode Q2 is connected to the resistor R3 to the negative pole of the power supply, the capacitor C1 is connected in parallel with the resistor R3, the emitter of the triode Q2 is connected to the negative pole of the power supply, and the collector of the triode Q2 is connected to the base of the triode Q1; thus forming a basic unit circuit; multiple groups of basic unit circuits can be connected according to needs, and the thermistors of each basic unit circuit are sequentially connected to the heat conductor, that is, starting from the heat source end, the thermistors of each basic unit are connected at the spaced sampling points; the optocoupler output terminal of the voice control circuit 5 of the basic unit circuit is connected to the two contact points at both ends of the corresponding number button of the electronic voice calculator, and when the optocoupler output terminal of the voice control circuit 5 is turned on and then off, when heat is transferred, the corresponding sequence indicator lights up and the corresponding number makes a sound; the heat conductor can be made of metals with different shapes and materials.

[0005] Working process: In this case, taking four groups of unit circuits A, B, C, and D as examples, when conducting a demonstration experiment, the power supply is turned on, and one end or a point of it is heated with a heat source such as an alcohol lamp. As heat is transferred, heat transfers from the end with a higher temperature to the end with a lower temperature. If heat transfers from the left end Z of the heat conductor to the right end Y of the heat conductor, and there are thermistors connected at intervals on the heat conductor. When heating the left end Z point, heat transfers along the heat conductor. The thermistors RT1, RT2, RT3, and RT4 are connected in sequence. The thermistors are negative temperature coefficient thermistors, and their resistance values decrease as the temperature increases. Through the sampling and recognition of the precision voltage reference integrated circuit KA1, the LED lamp groups of each basic unit circuit are lit in sequence. The lamp groups can be composed of LED lamps of different colors. If the other end of the heat conductor is heated, the LED lamp groups will be lit in reverse sequence. The output ends of the optocouplers of the basic unit circuits are connected to both ends of the button of the "corresponding number" (when there are four groups of unit circuits, the numbers are 1, 2, 3, and 4) of the electronic voice calculator, and the contacts at both ends are connected to control the digital voice to sound in the corresponding sequence. After the output end of the optocoupler is connected and then disconnected, it is convenient for subsequent control;

[0006] Taking the basic unit circuit A as an example, heat transfers along the heat conductor. The resistance value of the thermistor RT1 decreases as the temperature increases. The precision voltage reference integrated circuit KA1 conducts, and through the optocoupler PC2, the LED lamp group TD1 emits light. The power supply makes the triode Q1 conduct through the output end of the optocoupler PC2 and the resistor R2. The output end of the optocoupler PC1 conducts, making the contacts at both ends of the button of the "corresponding number" with the number 1 connected to the electronic voice calculator conduct, controlling the digital voice to sound in the corresponding sequence, that is, the output end of the optocoupler PC1 conducts, that is, the contact end of the button with the number "1" connected to the electronic voice calculator conducts, and the electronic voice calculator sounds "1"; At the same time, the power supply charges the capacitor C1 through the optocoupler PC2 and the resistor R4. After the capacitor C1 is charged and delayed, the triode Q2 conducts, and the triode Q1 is kept cut off. The output end of the optocoupler PC1 is cut off and maintained until the power supply is cut off, which is convenient for subsequent unit circuit control; Similarly, the control process of the subsequent unit circuits is the same; After the experiment is completed, the heat source is cut off, the heat conductor cools, the resistance value of the thermistor becomes larger, the precision voltage reference integrated circuit KA1 is cut off, and the charging voltage of the capacitor C1 is discharged through the resistor R3, and the circuit is reset; Or after the power supply is cut off, the charging voltage of the capacitor C1 is discharged through the resistor R3; Wait for the next power-on and startup. The working processes of each group of unit circuits are the same.

[0007] Heat is transferred along the heat conductor. The resistance value of the thermistor RT1 decreases as the temperature rises. After being sampled and identified by the precision voltage reference integrated circuit, the LED lamp groups of each basic unit circuit are lit in sequence. The lamp groups can be composed of LED lamps of different colors. When connecting the output end of the optocoupler PC1 of the sound control circuit, pay attention to the high and low ends of the signals at both contact points of the corresponding digital button. The delay time is determined according to the need by the sizes of the delay capacitor C1 and the resistor R3. Ensure that the output end of the optocoupler PC1 of the sound control circuit is connected for 1 to 2 seconds and then disconnected, so as to facilitate subsequent sound control and other function controls.

[0008] Effect: The sound and light demonstration heat transfer device has a good demonstration experiment effect. The LED lamps have high brightness and low power consumption, enabling energy-saving demonstration. As heat is transferred, heat is transferred from the end with a higher temperature to the end with a lower temperature. The LED lamp groups of different colors are lit in sequence, and numbers are sounded in the corresponding order. If the other end of the heat conductor is heated, the LED lamp groups will be lit in reverse sequence, and the order of number sounding will also be reversed. The sound and light display is vivid, specific, intuitive, eye-catching, novel and practical. There is no matchstick dropping, and it is not affected by the amount of pasted vaseline and the paste fastness. The circuit is simple, with low cost, stable and reliable. After the power supply is disconnected and the heat conductor is cooled with water, the experiment can be carried out again in a short time. Description of the drawings:

[0009] Figure 1 It is a structural diagram of the sound and light demonstration heat transfer device of the present invention.

[0010] Figure 2 It is a schematic diagram of the sound and light demonstration heat transfer device of the present invention.

[0011] Figure 1 、 Figure 2 In [drawings], 1 is the heat conductor, 2 is the thermistor, 3 is the identification and drive circuit, 4 is the LED lamp group, 5 is the sound control circuit; in this case, four groups of basic unit circuits are taken as an example, where: TD1-4 are LED lamp groups for light emission display, C1-4 are capacitors, PC1-8 are optocouplers, Q1-8 are triodes, R1-28 are resistors, RT1-4 are thermistors, and KA1-4 are precision voltage reference integrated circuits. Specific implementation method:

[0012] The sound and light demonstration heat transfer device is composed of a heat conductor, a thermistor, an identification and drive circuit, an LED lamp group, and a sound control circuit; in this case, four groups of basic unit circuits are taken as an example, where: TD1-4 are LED lamp groups for light emission display, C1-4 are capacitors, PC1-8 are optocouplers, Q1-8 are triodes, R1-28 are resistors, RT1-4 are thermistors, and KA1-4 are precision voltage reference integrated circuits.

[0013] In addition to heating with open flames such as alcohol lamps and candles, electric heating can also be used, or directly heated with an electric soldering iron. Remove the soldering iron tip, and the heat conductor is directly fixed at the original position of the soldering iron tip. Multiple groups of basic unit circuits can be connected as needed. The thermistors of each basic unit circuit are sequentially connected to the heat conductor, that is, starting from the heat source end, thermistors are connected at the spaced sampling points; the heat conductor can be replaced with metal of other shapes. For example, the heat conductor can be a copper rod with a length of 15 cm and a cross-section of 1-4 square millimeters. The thermistors connected at the sampling points can be crimped or soldered with solder of a relatively high melting point. If the copper rod is shorter and smaller, and the interval of the thermistors is shorter, the experimental time can be saved.

[0014] Taking four groups of basic unit circuits as an example in this case, the basic unit circuits are A-D. First, take a basic unit circuit A as an example to illustrate. When doing a demonstration experiment, turn on the power supply and heat one end or a point thereof with a heat source such as an alcohol lamp. As heat is transferred, heat is transferred from the end with a higher temperature to the end with a lower temperature. If heat is transferred from the left end Z of the heat conductor to the right end Y of the heat conductor, thermistors are connected at intervals on the heat conductor. When heating the left end Z point, heat is transferred along the heat conductor. The thermistors RT1, RT2, RT3, and RT4 are connected in sequence. The thermistors are negative temperature coefficient thermistors, and their resistance values decrease as the temperature increases; through the sampling and recognition of the precision voltage reference integrated circuit KA1, the LED lamp groups of each basic unit circuit are sequentially lit. The lamp group can be composed of LED lamps of different colors. If heated at the other end of the heat conductor, the LED lamp group will be lit in reverse sequence. The output end of the optocoupler of the basic unit circuit is connected to both ends of the button of the "corresponding number" (when there are four groups of unit circuits, the numbers are 1, 2, 3, 4) of the electronic voice calculator to control the voice emission of the corresponding sequence of numbers. After the output end of the optocoupler is turned on and then turned off, it is convenient for subsequent control;

[0015] Taking the basic unit circuit A as an example, heat is transferred along the heat conductor. The resistance value of the thermistor RT1 decreases as the temperature rises. The precision voltage reference integrated circuit KA1 conducts, and through the optocoupler PC2, the LED lamp group TD1 emits light. The power supply makes the triode Q1 conduct through the output terminal of the optocoupler PC2 and the resistor R2. The output terminal of the optocoupler PC1 conducts, making the contacts at both ends of the button corresponding to the "corresponding digit" of the electronic voice calculator with the digit 1 connected, controlling the digital voice to sound in the corresponding order. That is, the output terminal of the optocoupler PC1 conducts, that is, the contacts at the button end of the digit "1" of the electronic voice calculator conduct, and the electronic voice calculator sounds "1"; at the same time, the power supply charges the capacitor C1 through the optocoupler PC2 and the resistor R4. After the capacitor C1 is charged and delayed, the triode Q2 conducts, and the triode Q1 is kept cut off. The output terminal of the optocoupler PC1 is cut off and maintained until the power supply is cut off, facilitating the control of subsequent unit circuits; after the experiment is completed, the heat source is cut off, the heat conductor cools, the resistance value of the thermistor becomes larger, the precision voltage reference integrated circuit KA1 is cut off, and the charging voltage of the capacitor C1 is discharged through the resistor R3, and the circuit is reset; or after the power supply is cut off, the charging voltage of the capacitor C1 is discharged through the resistor R3; wait for the next power-on and start. The working processes of each group of unit circuits are the same.

[0016] Through the sampling and recognition of the precision voltage reference integrated circuit, the LED lamp groups of each basic unit circuit are sequentially lit. The lamp group can be composed of LED lamps of different colors; when connecting the output terminal of the optocoupler, pay attention to the high and low ends of the signal at both ends of the corresponding digit button; the delay time is determined according to the need by the size of the delay capacitor C1 and the resistor R3; ensure that the output terminal of the optocoupler PC1 is connected for 1 to 2 seconds and then disconnected, so as to facilitate subsequent sound control and other function controls. The heat conductor can be replaced by metals of other shapes, and the power supply of this circuit can be powered by a 12V power supply.

[0017] The acousto-optic demonstration heat transfer device has a good demonstration experiment effect. The LED lamps have high brightness and low power consumption, and can be used for energy-saving demonstration. As heat is transferred, heat is transferred from the end with a higher temperature to the end with a lower temperature. The LED lamp groups of different colors are sequentially lit, and the digits sound in the corresponding order. If the other end of the heat conductor is heated, the LED lamp groups will be lit in reverse order, and the digital sound sequence will also be reversed. The acousto-optic display is vivid, specific, intuitive and eye-catching, novel and practical. There is no matchstick dropping, and it is not affected by the amount and adhesion strength of the pasted vaseline. The circuit is simple, with low cost, stable and reliable. After the power supply is disconnected and the heat conductor is cooled with water, the experiment can be carried out again in a short time.

Claims

1. Acousto-optic demonstration heat transfer device, Characterized in that, It consists of a heat conductor (1), a thermistor (2), an identification drive circuit (3), an LED lamp group (4), and a voice control circuit (5); the positive pole of the power supply is connected to the heat conductor (1), the heat conductor (1) is connected to the sampling terminal of the precision voltage reference integrated circuit KA1 of the thermistor (2) RT1 to the identification drive circuit (3), the sampling terminal of the precision voltage reference integrated circuit KA1 of the identification drive circuit (3) is connected to the resistor R7 to the negative pole of the power supply, the ground terminal of the precision voltage reference integrated circuit KA1 of the identification drive circuit (3) is connected to the negative pole of the power supply, the control terminal of the precision voltage reference integrated circuit KA1 of the identification drive circuit (3) is connected to the negative terminal of the input of the resistor R6 and the optocoupler PC2, the positive terminal of the input of the optocoupler PC2 is connected to the positive pole of the power supply, the positive terminal of the output of the optocoupler PC2 to the positive pole of the power supply, the negative terminal of the output of the optocoupler PC2 of the identification drive circuit (3) is connected to the resistor R5, the LED lamp group (4) TD1, to the negative pole of the power supply, the negative terminal of the output of the optocoupler PC2 of the identification drive circuit (3) is connected to the resistor R2 of the voice control circuit (5) to the base of the triode Q1, the emitter of the triode Q1 is connected to the negative pole of the power supply, the collector of the triode Q1 is connected to the positive pole of the power supply through the resistor R1 and the input of the optocoupler PC1, and the output of the optocoupler PC1 is connected to the two contact points at both ends of the corresponding digital button of the electronic voice calculator. When connecting, pay attention to the high and low ends of the signals at both contact points of the corresponding digital button; the negative terminal of the output of the optocoupler PC2 of the identification drive circuit (3) is connected to the resistor R4 of the voice control circuit (5) to the base of the triode Q2, the base of the triode Q2 is connected to the resistor R3 to the negative pole of the power supply, the capacitor C1 is connected in parallel with the resistor R3, the emitter of the triode Q2 is connected to the negative pole of the power supply, and the collector of the triode Q2 is connected to the base of the triode Q1; thus forming a basic unit circuit; multiple groups of basic unit circuits can be connected as needed, and the thermistors of each basic unit circuit are sequentially connected to the heat conductor, that is, starting from the heat source end, the thermistors of each basic unit are connected at the spaced sampling points; the optocoupler output terminal of the voice control circuit (5) of the basic unit circuit is connected to the two contact points at both ends of the corresponding digital button of the electronic voice calculator. When the optocoupler output terminal of the voice control circuit (5) is turned on and then off, when heat is transferred, the corresponding sequence indicator lights up and the corresponding number makes a sound; the heat conductor can be made of metals with different shapes and materials, and the circuit power supply is a 12V power supply.

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