CN202939517U - Low-power consumption temperature control circuit of portable refrigerator - Google Patents

Abstract

The utility model discloses a low-power consumption temperature control circuit of a portable refrigerator. The temperature control circuit comprises a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a first diode, a voltage-stabilizing tube, a second diode, a slide rheostat, a second slide rheostat, a first voltage comparator, a voltage comparator, a first NAND gate, a second NAND gate, a triode, a storage battery and a solar cell panel.

Description

Low power consumption temperature control circuit for portable refrigerator

technical field

The utility model relates to the control field, in particular to a low-power consumption temperature control circuit of a portable refrigerator.

Background technique

At present, refrigerators have been popularized in every household, and recently car refrigerators have appeared on the market. People can also drink iced drinks in summer and bring food that is afraid of heat (such as meat) when traveling or working in the field. Make people enjoy life better. The car refrigerator has been well applied. But if you go to some suburban areas where cars can't reach, you can't meet the above needs. Therefore, need to develop a kind of portable energy-saving mini-refrigerator, to satisfy people's living needs.

Portable small refrigerators use solar photovoltaic power generation to convert light energy into electrical energy, and the output electrical energy is supplied to semiconductor refrigeration chips for direct cooling. It is characterized by portability, cleanliness, pollution-free and harmful, and long life. However, portable energy-saving small refrigerators are limited by power consumption. If the control circuit design is unreasonable, it is difficult to achieve the same cooling effect as a car refrigerator. Therefore, the low power consumption temperature control circuit of the portable energy-saving small refrigerator is an urgent problem to be solved.

Utility model content

The utility model provides a low power consumption temperature control circuit for a portable refrigerator, which is characterized in that it comprises: a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor Resistor, first diode, Zener tube, second diode, first sliding rheostat, second sliding rheostat, first voltage comparator, second voltage comparator, first NAND gate, second NAND Inverter, triode, storage battery and solar battery panel, wherein the positive pole of the solar battery panel is connected to the anode of the first diode, the cathode of the first diode is connected to the positive pole of the battery, and the negative pole of the solar battery panel is connected to the battery The positive pole of the battery is connected to the cathode of the voltage regulator tube, one end of the first resistor, one end of the second resistor and one end of the third resistor, and the negative pole of the battery is connected to the anode of the voltage regulator tube and the second diode Cathode, one end of the fourth resistor and one end of the fifth resistor, the other end of the first resistor is connected to the anode of the second diode, the non-inverting input end of the first voltage comparator and the negative input end of the second voltage comparator phase input end, the other end of the second resistor is connected to one fixed end of the first sliding rheostat, the other end of the fourth resistor is connected to the other fixed end of the first sliding rheostat, and the sliding end of the first sliding rheostat is connected to The inverting input terminal of the first voltage comparator, the other end of the third resistor is connected to a fixed end of the second sliding rheostat, the other end of the fifth resistor is connected to the other fixed end of the second sliding rheostat, the The sliding end of the second sliding rheostat is connected to the non-inverting input end of the second voltage comparator, the output end of the first voltage comparator is connected to an input end of the first NAND gate, and the output end of the second voltage comparator is connected to the first NAND gate. One input end of two NAND gates, the other input end of the second NAND gate is connected to the output end of the first NAND gate, and the output end of the second NAND gate is connected to the other input end of the first NAND gate and the base of the triode, the collector of the triode is connected to one end of the sixth resistor and one end of the load, the emitter of the triode is connected to the other end of the load, and the other end of the sixth resistor is connected to a 12V power supply.

Wherein, the load is a semiconductor refrigerator.

Wherein, the resistance value of the first resistor is 57 kohms, the resistance value of the second resistor is 770 kohms, the resistance value of the third resistor is 770 kohms, the resistance value of the fourth resistor is 100 kohms, The fifth resistor has a resistance value of 100 kohms and the sixth resistor has a resistance value of 5.1 kohms.

Wherein, the resistance range of the first sliding rheostat is 0-33 kohms and the resistance range of the second sliding resistor is 0-33 kohms.

Beneficial effect:

The low power consumption temperature control circuit of the portable refrigerator provided by the utility model is simple, stable and reliable, and can well solve the power consumption problem of the portable small refrigerator, so that this kind of refrigerator can achieve the expected refrigeration or heat preservation with the minimum power consumption Effect.

Description of drawings

FIG. 1 is a schematic schematic diagram of a low power consumption temperature control circuit of a portable refrigerator of the present invention.

Detailed ways

As shown in Figure 1, the low power consumption temperature control circuit of the portable refrigerator of the present invention includes: a first resistor 1, a second resistor 2, a third resistor 3, a fourth resistor 4, and a fifth resistor 5 , the first diode 6, the Zener tube 7, the second diode 8, the first sliding rheostat 9, the second sliding rheostat 10, the first voltage comparator 11, the second voltage comparator 12, the first and A NOT gate 13 , a second NAND gate 14 , a sixth resistor 15 , a triode 16 , a storage battery 17 and a solar panel 18 . In addition, the output end of the triode is connected to a load 19, where the load is a semiconductor refrigerator. Wherein, the anode of the solar battery panel 18 is connected to the anode of the first diode 6, the cathode of the first diode 6 is connected to the positive pole of the battery 17, the negative pole of the solar battery panel 18 is connected to the negative pole of the battery 17, and the positive pole of the battery 17 is connected to The cathode of the voltage regulator tube 7, one end of the first resistor 1, one end of the second resistor 2 and one end of the third resistor 3, the negative pole of the battery 17 is connected to the anode of the voltage regulator tube 7, the second diode 8 cathode, one end of the fourth resistor 4 and one end of the fifth resistor 5, the other end of the first resistor 1 is connected to the anode of the second diode 8, the non-inverting input end of the first voltage comparator 11 and the second The inverting input terminal of the voltage comparator 12, the other end of the second resistor 2 is connected to a fixed end of the first sliding rheostat 9, and the other end of the fourth resistor 4 is connected to the other fixed end of the first sliding rheostat 9 , the sliding end of the first sliding rheostat 9 is connected to the inverting input end of the first voltage comparator 11, the other end of the third resistor 3 is connected to a fixed end of the second sliding rheostat 10, and the fifth resistor 5 The other end of the second sliding rheostat 10 is connected to the other fixed end, the sliding end of the second sliding rheostat 10 is connected to the non-inverting input end of the second voltage comparator 12, and the output end of the first voltage comparator 11 is connected to the first An input terminal of the NAND gate 13, an output terminal of the second voltage comparator 12 is connected to an input terminal of the second NAND gate 14, and the other input terminal of the second NAND gate 14 is connected to the first NAND gate 13 The output terminal of the second NAND gate 14 is connected to the other input terminal of the first NAND gate 13 and the base of the triode 16, and the collector of the triode 16 is connected to one end of the sixth resistor 15 and the semi-conductor refrigerator. One end of the resistor 19, the emitter of the triode 16 is connected to the other end of the semiconductor refrigerator 19, and the other end of the sixth resistor 15 is connected to a 12V power supply.

Those skilled in the art know: the resistance values of the first resistor, the second resistor, the third resistor, the fourth resistor, the fifth resistor and the sixth resistor, the first sliding rheostat and the second sliding resistor The resistance range of the device can be set according to the actual design needs of the circuit.

In the present utility model, the resistance value of the first resistor is 57 kilohms, the resistance value of the second resistor is 770 kilohms, the resistance value of the third resistor is 770 kilohms, and the resistance value of the fourth resistor is 100 kohms, the resistance value of the fifth resistor is 100 kohms, the resistance value of the sixth resistor is 5.1 kohms, the resistance range of the first sliding rheostat is 0~33 kohms, and the resistance value of the second sliding resistor The resistance range is 0~33 kohms.

In addition, the 12V power supply connected to the other end of the sixth resistor can be realized through the combination of the storage battery 17 and the regulator tube 7 .

In addition, although the utility model discloses using solar panels to charge the storage battery, those skilled in the art know that the national grid can also be used to charge the storage battery.

The basic working principle of the utility model: first utilize the solar panel 18 to convert solar energy into electric energy, and charge the storage battery 17 through the first diode 6 . The first diode 6 can prevent the storage battery 17 from discharging through the solar panel 18 when the solar panel 18 does not generate electricity or a short circuit fault occurs. The storage battery 17 outputs a stable voltage through the regulator tube 7 . In the present invention, the stable voltage is 12V. The first resistor 1 acts as a voltage divider to prevent the second diode 8 from burning out. Near room temperature, every time the temperature rises by 1°C, the forward voltage drop of the diode decreases by 2-2.5mV. The low power consumption temperature control circuit of the present invention is based on the characteristic that the diode is sensitive to temperature. Diode 8 to detect the temperature of the portable small refrigerator. Taking the measured voltage and temperature across the second diode as an example, when the temperature is between -10 and 30°C, the voltage across the second diode varies linearly with temperature, and the variation range is UL ~UH, where UL=0V, UH=5V. The cooling stop temperature TWL (-10°C≤TWL≤30°C) is set through the first sliding rheostat 9, and the second resistor 2 and the fourth resistor 4 are voltage limiting resistors. When the resistance value of the first sliding rheostat 9 is adjusted from 0 to 33 kohms (that is, adjusted from zero to full scale), the voltage input to the first comparator 11 varies between UL~UH (0~5V). The start cooling temperature TWH (-10°C≤TWH≤30°C) is set through the second sliding rheostat 10, and the third resistor 3 and the fifth resistor 5 are voltage limiting resistors. When the resistance value of the second sliding rheostat 10 is adjusted from 0 to 33 kohms (that is, adjusted from zero to full scale), the voltage input to the second comparator 12 varies between UL~UH (0~5V).

For ease of description, a switch is shown in Fig. 1 of the present utility model, but those skilled in the art know that no matter whether the switch exists or not, it has no influence on the design of the low power consumption temperature control circuit of the portable refrigerator. If no switch is installed, it can be equivalently considered that the switch is normally closed. The following is a brief description of the working process of the low-power temperature control circuit of the portable refrigerator: when the switch is closed, before cooling, T≥TWH, when the semiconductor refrigerator is not working, that is, when the second NAND gate 14 outputs a low level, the The structure of the low-power temperature control circuit shows that in the next state, the second NAND gate 14 outputs a high level, the triode 16 is turned on, and the semiconductor refrigerator is controlled to start working; when the semiconductor refrigerator works, the second NAND gate When 14 outputs a high level, it can be seen from the structure of the low power consumption temperature control circuit that in the next state, the second NAND gate 14 outputs a high level, and the semiconductor refrigerator continues to work. When TWL≤T≤TWH and the second NAND gate 14 outputs a high level, the semiconductor refrigerator continues to work until T<TWL and the second NAND gate 14 outputs a high level, the next state the second NAND gate 14 outputs Low level, semiconductor refrigerator stops working. Wait for the portable refrigerator to heat up. When TWL≤T≤TWH, the second NAND gate 14 outputs a low level at this time, the semiconductor refrigerator does not work, and the portable refrigerator is in a heat preservation state; until T>TWH, the semiconductor refrigerator starts to work , in turn the process loop works.

Beneficial effect:

The low power consumption temperature control circuit of the portable refrigerator provided by the utility model is simple, stable and reliable, and can well solve the power consumption problem of the portable small refrigerator, so that this kind of refrigerator can achieve the expected refrigeration or heat preservation with the minimum power consumption Effect.

Claims (4)

1. A low power consumption temperature control circuit for a portable refrigerator, characterized in that it comprises: a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, The first diode, the Zener tube, the second diode, the first sliding rheostat, the second sliding rheostat, the first voltage comparator, the second voltage comparator, the first NAND gate, the second NAND gate, A triode, a storage battery and a solar cell panel, wherein the positive pole of the solar cell panel is connected to the anode of the first diode, the cathode of the first diode is connected to the positive pole of the storage battery, and the negative pole of the solar cell panel is connected to the negative pole of the storage battery, The positive pole of the battery is connected to the cathode of the Zener tube, one end of the first resistor, one end of the second resistor and one end of the third resistor, and the negative pole of the battery is connected to the anode of the Zener tube, the cathode of the second diode, and the third resistor. One end of the four resistors and one end of the fifth resistor, the other end of the first resistor is connected to the anode of the second diode, the non-inverting input of the first voltage comparator and the inverting input of the second voltage comparator , the other end of the second resistor is connected to one fixed end of the first sliding rheostat, the other end of the fourth resistor is connected to the other fixed end of the first sliding rheostat, and the sliding end of the first sliding rheostat is connected to the first The inverting input terminal of the voltage comparator, the other end of the third resistor is connected to a fixed end of the second sliding rheostat, the other end of the fifth resistor is connected to the other fixed end of the second sliding rheostat, and the second sliding The sliding end of the rheostat is connected to the non-inverting input end of the second voltage comparator, the output end of the first voltage comparator is connected to an input end of the first NAND gate, and the output end of the second voltage comparator is connected to the second NAND gate. One input terminal of the gate, the other input terminal of the second NAND gate is connected to the output terminal of the first NAND gate, and the output terminal of the second NAND gate is connected to the other input terminal of the first NAND gate and the transistor. The base, the collector of the triode is connected to one end of the sixth resistor and one end of the load, the emitter of the triode is connected to the other end of the load, and the other end of the sixth resistor is connected to a 12V power supply. 2. The low power consumption temperature control circuit of a portable refrigerator according to claim 1, wherein the load is a semiconductor refrigerator. 3. The low power consumption temperature control circuit of a portable refrigerator according to claim 1, wherein the resistance value of the first resistor is 57 kilohms, the resistance value of the second resistor is 770 kilohms, and the third resistor The resistor has a resistance of 770 kohms, the fourth resistor has a resistance of 100 kohms, the fifth resistor has a resistance of 100 kohms and the sixth resistor has a resistance of 5.1 kohms. 4. The low power consumption temperature control circuit of the portable refrigerator according to claim 1, characterized in that the resistance range of the first sliding rheostat is 0~33 kohms and the resistance range of the second sliding resistor is 0~33 kohms. 33 kohms.

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