Refrigerator heating wire power modulation circuit

Abstract

The invention discloses a refrigerator heating wire power modulation circuit which comprises a controller used for outputting a control signal to control a heating wire of a refrigerator to work, a switch module used for outputting power supply voltage of the heating wire according to the control signal output by the controller, and a power supply module used for supplying power to the heating wire according to the power supply voltage. The output capacitor is used for receiving the power supply voltage output by the switch module for charging and supplying power to the heating wire through discharging; the input end of the switch module is used for being connected with a power supply end, the control end of the switch module is connected with the control signal output end of the controller, and the output end of the switch module is connected with the power supply end of the heating wire; the first end of the output capacitor is connected with the output end of the switch module, and the second end of the output capacitor is grounded. According to the invention, continuous power supply to the heating wire can be realized through the output capacitor, temperature fluctuation of the heating wire caused by repeated start and stop of the heating wire is avoided, and continuous adjustment of the heating power is realized.

Description

Technical Field

[0001] The invention relates to the technical field of refrigerators, and in particular to a refrigerator heating wire power modulation circuit. Background Art

[0002] With the popularity of frost-free refrigerators, more and more refrigerators use air cooling mode for refrigeration. In air-cooled refrigerators, frost will form on the evaporator, which will affect the refrigeration efficiency of the refrigerator. Usually, a defrosting heating wire is used to defrost the evaporator.

[0003] The current defrost heating wire control method is switch control, which controls the heating wire by repeatedly switching on and off. This control method causes large temperature fluctuations when the heating wire switch is switched, and the power of the heating wire cannot be controlled. Summary of the invention

[0004] The purpose of the embodiment of the present invention is to provide a refrigerator heating wire power modulation circuit, which can realize continuous adjustable heating power of the heating wire and small temperature fluctuation.

[0005] An embodiment of the present invention provides a refrigerator heating wire power modulation circuit, comprising:

[0006] The controller is used to output a control signal to control the operation of the heating wire of the refrigerator:

[0007] A switch module, used for outputting a power supply voltage of the heating wire according to a control signal output by the controller;

[0008] An output capacitor, used to receive the power supply voltage output by the switch module for charging, and to supply power to the heating wire by discharging;

[0009] The input end of the switch module is used to connect to the power supply end, the control end of the switch module is connected to the output end of the control signal of the controller, and the output end of the switch module is connected to the power supply end of the heating wire; the first end of the output capacitor is connected to the output end of the switch module, and the second end of the output capacitor is grounded.

[0010] Preferably, the circuit further includes a temperature acquisition module;

[0011] The controller collects the temperature of the heating wire through the temperature collection module, and outputs a control signal to the switch module according to the collected temperature.

[0012] As a preferred solution, the circuit further includes an inductor:

[0013] The first end of the output capacitor is connected to the output end of the switch module, specifically:

[0014] The first end of the output capacitor is connected to the output end of the switch module through the inductor.

[0015] Preferably, the switch module specifically includes a driving unit and a switch unit;

[0016] The driving unit is used to drive the switch unit;

[0017] The switch unit is used to control the switch module to be turned on or off;

[0018] The input end of the switch unit serves as the input end of the switch module, and the output end of the switch unit serves as the output end of the switch module;

[0019] The control end of the switch unit is connected to the input end of the drive unit, the output end of the drive unit is grounded, and the control end of the drive unit serves as the control end of the switch module.

[0020] As an improvement of the above solution, the switch module further includes a voltage stabilizing unit;

[0021] The voltage stabilizing unit is used to stabilize the output end of the switch module;

[0022] The output end of the switch unit is connected to the input end of the voltage stabilizing unit, and the output end of the voltage stabilizing unit is grounded.

[0023] Preferably, the driving unit comprises a first switch tube, a first resistor, a second resistor and a third resistor;

[0024] The first end of the first resistor serves as the input end of the driving unit, the second end of the first resistor is connected to the input end of the first switch tube, the second end of the first switch tube is grounded, the control end of the first switch tube is connected to the first end of the second resistor, and the second end of the second resistor serves as the control end of the driving unit;

[0025] The control end of the first switch tube is also grounded through the third resistor.

[0026] As a preferred solution, the switch unit includes a second switch tube and a fourth resistor;

[0027] The input end of the second switch tube serves as the input end of the switch unit, the output end of the second switch tube serves as the output end of the switch unit, and the control end of the second switch tube serves as the control end of the switch unit;

[0028] The input end of the second switch tube is also connected to its control end through the fourth resistor.

[0029] Preferably, the voltage stabilizing unit specifically includes a voltage stabilizing tube;

[0030] The anode of the voltage regulator tube serves as the input end of the voltage regulator unit, and the cathode of the voltage regulator tube serves as the output end of the voltage regulator unit.

[0031] As an improvement of the above solution, the voltage stabilizing unit further includes a third switch tube and a fifth resistor:

[0032] The input end of the third switch tube is connected to the anode of the voltage regulator tube, the output end of the third switch tube is connected to the cathode of the voltage regulator tube, and the control end of the third switch tube is connected to the control end of the switch unit through the fifth resistor.

[0033] Preferably, the temperature acquisition module specifically includes a thermistor, a sixth resistor, a seventh resistor and a first capacitor;

[0034] The thermistor is installed close to the heating wire;

[0035] The first end of the sixth resistor is used to connect to the power supply end, and the second end of the sixth resistor is grounded through the thermistor;

[0036] The second end of the sixth resistor is also connected to the first end of the seventh resistor, and the second end of the seventh resistor is connected to the temperature collection end of the controller;

[0037] The second end of the seventh resistor is also grounded through the first capacitor.

[0038] Compared with the prior art, the refrigerator heating wire power modulation circuit disclosed in the present invention includes a controller for outputting a control signal to control the operation of the heating wire of the refrigerator: a switch module for outputting the power supply voltage of the heating wire according to the control signal output by the controller; an output capacitor for receiving the power supply voltage output by the switch module for charging, and supplying power to the heating wire by discharging; the input end of the switch module is used to connect the power supply end, the control end of the switch module is connected to the output end of the control signal of the controller, and the output end of the switch module is connected to the power supply end of the heating wire; the first end of the output capacitor is connected to the output end of the switch module, and the second end of the output capacitor is grounded. The present application can realize continuous power supply to the heating wire through the output capacitor, avoid repeated starting and stopping of the heating wire, resulting in temperature fluctuations generated by the heating wire, and realize continuous regulation of the heating power. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 is a structural schematic diagram of a refrigerator provided by an embodiment of the present invention;

[0040] Figure 2 is a schematic structural diagram of a refrigeration system of a refrigerator provided in an embodiment of the present invention;

[0041] Figure 3is a schematic structural diagram of a refrigerator heating wire power modulation circuit provided by the present invention in a first embodiment;

[0042] Figure 4 is a schematic diagram of the structure of a voltage conversion circuit provided by an embodiment of the present invention;

[0043] Figure 5 A schematic diagram of the structure of a refrigerator heating wire power modulation circuit provided by the present invention in a second embodiment;

[0044] Figure 6 A schematic diagram of the structure of a refrigerator heating wire power modulation circuit in a third embodiment provided by the present invention;

[0045] Figure 7 A schematic diagram of the structure of a refrigerator heating wire power modulation circuit in a fourth embodiment provided by the present invention;

[0046] Figure 8 A schematic diagram of the structure of a refrigerator heating wire power modulation circuit in a fifth embodiment provided by the present invention;

[0047] Fig. 9 A schematic diagram of the structure of a sixth embodiment of a refrigerator heating wire power modulation circuit provided by the present invention;

[0048] Fig.10 It is a schematic diagram of the structure of the temperature acquisition module provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0049] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0050] In the description of the present application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0051] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0052] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0053] See also Figure 1 , is a structural schematic diagram of a refrigerator provided by an embodiment of the present invention. The embodiment of the present invention provides a refrigerator, including a box body 101, in which a storage chamber 102 is provided, including a refrigerator chamber and / or a freezer chamber for storing items with preservation or freezing requirements, and also includes a refrigeration system 104 for performing refrigeration operations of the refrigerator.

[0054] It should be noted that the refrigerator performs refrigeration operation through the refrigeration system to provide cold energy to the storage chamber so as to maintain the storage chamber at a constant low temperature. Figure 2 , is a schematic diagram of the refrigeration system structure of the refrigerator provided in an embodiment of the present invention, the refrigeration system is composed of a compressor 201, a condenser 202, a drying filter 203, a capillary 204, and an evaporator 205, and the working structure of the refrigeration system includes a compression process, a condensation process, a throttling process and an evaporation process.

[0055] The compression process is as follows: plug in the power cord of the refrigerator, and when the box needs to be cooled, the compressor starts to work, and the low-temperature, low-pressure refrigerant is sucked into the compressor, compressed into high-temperature, high-pressure superheated gas in the compressor cylinder, and then discharged into the condenser; the condensation process is as follows: the high-temperature, high-pressure refrigerant gas dissipates heat through the condenser, the temperature continues to drop, and is gradually cooled to a saturated vapor at room temperature and high pressure, and further cooled to a saturated liquid, and the temperature no longer drops. The temperature at this time is called the condensation temperature. The pressure of the refrigerant remains almost unchanged during the entire condensation process; the throttling process is as follows: the condensed refrigerant saturated liquid flows into the capillary after the moisture and impurities are filtered out by the drying filter, and the refrigerant is throttled and depressurized through it, and the refrigerant becomes a wet vapor at room temperature and low pressure; the evaporation process is as follows: it then begins to absorb heat and vaporize in the evaporator, which not only reduces the temperature of the evaporator and its surroundings, but also turns the refrigerant into a low-temperature, low-pressure gas. The refrigerant coming out of the evaporator returns to the compressor again, repeating the above process, transferring the heat in the refrigerator to the air outside the box, and achieving the purpose of refrigeration.

[0056] It should be noted that the above embodiment is only a specific structure and working principle of a conventional refrigerator. The refrigerator disclosed in this embodiment may also have the structure of the above-mentioned existing refrigerator to achieve corresponding functions.

[0057] The refrigerator cools down the storage room through the evaporator of the refrigeration system. With the promotion and use of air-cooled refrigerators, more and more refrigerators use air-cooled models for refrigeration. In order to avoid frost on the evaporator affecting the refrigeration efficiency, air-cooled refrigerators will defrost the evaporator through the defrosting heating wire. However, when the defrosting heating wire is controlled by the existing air-cooled refrigerator, the operation of the heating wire is generally controlled when frost forms on the evaporator, and the heating is stopped when there is no frost on the evaporator. During the operation of the refrigerator, the heating wire is controlled by repeatedly switching on and off. This control process cannot directly power the heating wire. In order to achieve a frost-free effect, the heating wire needs to be started repeatedly. When starting or stopping, the temperature of the heating wire changes greatly.

[0058] In view of the above-mentioned defects of the prior art, the present application proposes a refrigerator heating wire power modulation circuit, wherein the circuit includes a controller for outputting a control signal to control the operation of the refrigerator heating wire:

[0059] A switch module, used for outputting a power supply voltage of the heating wire according to a control signal output by the controller;

[0060] An output capacitor, used to receive the power supply voltage output by the switch module for charging, and to supply power to the heating wire by discharging;

[0061] The input end of the switch module is used to connect to the power supply end, the control end of the switch module is connected to the output end of the control signal of the controller, and the output end of the switch module is connected to the power supply end of the heating wire; the first end of the output capacitor is connected to the output end of the switch module, and the second end of the output capacitor is grounded.

[0062] When this embodiment is implemented, see Figure 3 , is a schematic structural diagram of a refrigerator heating wire power modulation circuit provided by the present invention in a first embodiment.

[0063] The circuit includes a heating wire T, a controller, a switch module and an output capacitor C;

[0064] The heating wire T is installed close to the evaporator and defrosts the evaporator by heating the evaporator.

[0065] The controller is used to output control signals to control the operation of the heating wire T:

[0066] The switch module is used to output the power supply voltage of the heating wire according to the control signal output by the controller;

[0067] The output capacitor C is used to receive the power supply voltage output by the switch module for charging, and to supply power to the heating wire T through discharge;

[0068] The circuit structure is specifically as follows: the input terminal IN of the switch module is used to connect the power supply VCC1, the output terminal OUT of the switch module is connected to the power supply terminal of the heating wire, that is, the first end of the heating wire, the second end of the heating wire is grounded, and the control signal output terminal Heat-con of the controller is connected to the control terminal CON of the switch module. The first end of the output capacitor C is connected to the output end of the switch module, and the second end of the output capacitor C is grounded.

[0069] It should be noted that the switch module is specifically a device component that can output the power supply voltage of the heating wire according to the control signal output by the controller, and can be specifically composed of a switch tube, and can also be composed of other modules that can achieve the above functions.

[0070] The controller needs to be powered by the power supply end during specific operation. Since the external power supply end is powered by 12V as a whole, but the rated voltage of the power supply end of the controller is 5V, a voltage conversion circuit is required to convert the voltage and output the converted voltage to the power supply port VDD of the controller.

[0071] See also Figure 4 , is a schematic diagram of the structure of a voltage conversion circuit provided by an embodiment of the present invention. The voltage conversion circuit includes a voltage converter, a second capacitor and a third capacitor. An input terminal 1 of the voltage converter is connected to a 12V power supply, and an output terminal 3 of the voltage converter serves as a voltage output terminal of the voltage conversion circuit.

[0072] The output terminal 3 of the voltage converter is also connected to the first terminal of the second capacitor C2 and the first terminal of the third capacitor C3, and the second terminal of the second capacitor C2 and the second terminal of the third capacitor C3 are grounded. The voltage conversion module also includes a ground terminal 2. The 12V power supply voltage is converted into a 5V power supply voltage by the voltage conversion circuit and output to the power supply port VDD of the controller.

[0073] When the controller is working, it outputs a PWM control signal through the control signal output terminal Heat-con. The PWM control signal controls the switch module to be turned on or off. When the switch module is turned on, the supply voltage at its input end is loaded onto the output capacitor C to charge the output capacitor. When the switch module is turned off, the supply voltage on the input end cannot charge the output capacitor. After the output capacitor is charged, it supplies power to the heating wire through discharge.

[0074] By controlling the duty cycle of the PWM control signal, the charging and discharging time of the output capacitor is controlled, thereby determining the voltage output to the heating wire T. When the output duty cycle is large, the voltage of the heating wire is high, and when the output duty cycle is small, the voltage of the heating wire is low. The heating power can be continuously adjusted by the characteristics of the heating wire having different powers at different voltages.

[0075] The output capacitor can provide continuous power to the heating wire, thus avoiding repeated starting and stopping of the heating wire, which may cause temperature fluctuations in the heating wire.

[0076] In another embodiment provided by the present invention, the circuit further includes a temperature acquisition module;

[0077] The controller collects the temperature of the heating wire through the temperature collection module, and outputs a control signal to the switch module according to the collected temperature.

[0078] When this embodiment is implemented, see Figure 5 , is a schematic structural diagram of a refrigerator heating wire power modulation circuit provided by the present invention in a second embodiment;

[0079] The circuit also includes a temperature acquisition module, which is installed close to the heating wire T and connected to the signal acquisition terminal AD of the controller.

[0080] The temperature acquisition module is used to acquire the temperature of the heating wire, and convert the acquired temperature data into corresponding electrical signals, and output them to the controller.

[0081] In the specific implementation, the controller outputs the corresponding PWM signal to the switch module, controls the switch module to be turned on or off, and outputs the corresponding power supply voltage to the heating wire by charging the output capacitor, so that the heating wire works with the corresponding heating power to defrost the evaporator. In this process, the temperature of the heating wire is monitored, and the temperature value of the heating wire at this time is matched with the heating temperature required by the refrigerator in the current state. When the temperature of the heating wire is too high, the duty cycle of the output PWM signal is reduced to reduce the heating power of the heating wire. When the temperature of the heating wire is too low, the duty cycle of the output PWM signal is increased to increase the heating power of the heating wire.

[0082] The temperature of the heating wire is collected by the temperature acquisition module and fed back to the controller so that the controller can accurately monitor the temperature of the heating wire, control the duty cycle of the control signal accordingly, and realize precise control of the power of the heating wire to achieve the best defrosting effect and reduce power consumption.

[0083] In another embodiment of the present invention, the circuit further includes an inductor:

[0084] The first end of the output capacitor is connected to the output end of the switch module, specifically:

[0085] The first end of the output capacitor is connected to the output end of the switch module through the inductor.

[0086] When this embodiment is implemented, see Figure 6 , is a schematic structural diagram of a refrigerator heating wire power modulation circuit provided by the present invention in a third embodiment; the circuit also includes an inductor L.

[0087] The output terminal OUT of the switch module is connected to the first end of the inductor L, and the second end of the inductor L is connected to the first end of the output capacitor C.

[0088] When the control signal output by the controller controls the switch module to turn on, the VDD1 input at the input end of the switch module is loaded on both ends of the output capacitor C through the switch module and the inductor L to charge the output capacitor C. When the control signal output by the controller controls the switch module to turn off, the voltage at the input end of the switch module cannot be loaded on both ends of the output capacitor C, and the output capacitor C is charged through the freewheeling function of the inductor L.

[0089] The rate of current change is limited by the freewheeling function of the inductor. When the switch module switches from off to on or from on to off, the freewheeling inductor will store or release electrical energy to slow down the rate of change of the current, which can protect the circuit from the impact of sudden changes in voltage and current, improve the stability of the circuit, and charge the output capacitor through the freewheeling function of the inductor, which can improve the utilization of electrical energy and increase the power of the heating wire.

[0090] In another embodiment provided by the present invention, the switch module specifically includes a driving unit and a switch unit;

[0091] The driving unit is used to drive the switch unit;

[0092] The switch unit is used to control the switch module to be turned on or off;

[0093] The input end of the switch unit serves as the input end of the switch module, and the output end of the switch unit serves as the output end of the switch module;

[0094] The control end of the switch unit is connected to the input end of the drive unit, the output end of the drive unit is grounded, and the control end of the drive unit serves as the control end of the switch module.

[0095] When this embodiment is implemented, see Figure 7 , is a schematic diagram of the structure of the refrigerator heating wire power modulation circuit provided by the present invention in the fourth embodiment; the switch module specifically includes a driving unit and a switch unit;

[0096] The driving unit is used to drive the switch unit, and the switch unit is used to control the switch module to be turned on or off; the switch module is switched on or off by the driving unit driving the switch unit to be turned on or off.

[0097] Specifically, the input terminal IN1 of the switch unit serves as the input terminal IN of the switch module and is connected to the power supply VCC1, and the output terminal OUT1 of the switch unit serves as the output terminal OUT of the switch module and is connected to the first end of the output capacitor C;

[0098] The control terminal CON1 of the switch unit is connected to the input terminal IN2 of the drive unit, the output terminal OUT2 of the drive unit is grounded, and the control terminal CON2 of the drive unit serves as the control terminal CON of the switch module and is connected to the control signal output terminal Heat-con.

[0099] The controller controls the driving unit to be turned on or off by outputting a control signal to the driving unit. After the driving unit is turned on, it drives the switch unit to be turned on, thereby realizing the conduction of the switch module and outputting the power supply at the input end of the switch module to the output capacitor. After the driving unit is turned off, the switch unit is also turned off, thereby controlling the switch module to be turned off.

[0100] Through the control of the driving unit and the switch unit, the power supply VCC1 input to the switch module can be separated from the control signal output terminal Heat-con of the controller, thereby avoiding the influence of the power supply voltage on the controller, protecting the controller and improving the circuit stability.

[0101] In another embodiment provided by the present invention, the switch module further includes a voltage stabilizing unit;

[0102] The voltage stabilizing unit is used to stabilize the output end of the switch module;

[0103] The output end of the switch unit is connected to the input end of the voltage stabilizing unit, and the output end of the voltage stabilizing unit is grounded.

[0104] When this embodiment is implemented, see Figure 8 , is a schematic diagram of the structure of the refrigerator heating wire power modulation circuit provided by the present invention in the fifth embodiment; the switch module also includes a voltage stabilizing unit;

[0105] The voltage stabilizing unit is used to stabilize the output terminal OUT of the switch module to ensure the stability of the voltage output by the switch module, avoid the influence of voltage mutation on the working performance of the heating wire, and maintain the stability of the heating work.

[0106] Specifically, the output terminal OUT1 of the switch unit is connected to the input terminal IN3 of the voltage stabilizing unit, and the output terminal OUT3 of the voltage stabilizing unit is grounded.

[0107] It should be noted that the voltage stabilizing unit may be specifically composed of a voltage stabilizing diode, or may be composed of other voltage stabilizing devices.

[0108] In another embodiment of the present invention, the driving unit includes a first switch tube, a first resistor, a second resistor and a third resistor;

[0109] The first end of the first resistor serves as the input end of the driving unit, the second end of the first resistor is connected to the input end of the first switch tube, the second end of the first switch tube is grounded, the control end of the first switch tube is connected to the first end of the second resistor, and the second end of the second resistor serves as the control end of the driving unit;

[0110] The control end of the first switch tube is also grounded through the third resistor.

[0111] When this embodiment is implemented, see Fig. 9 , is a schematic diagram of the structure of the refrigerator heating wire power modulation circuit provided by the present invention in the sixth embodiment; the driving unit includes a first switch tube Q1, a first resistor R1, a second resistor R2 and a third resistor R3;

[0112] The first end of the first resistor R1 serves as the input end of the driving unit, the second end of the first resistor R1 is connected to the input end of the first switch tube Q1, the second end of the first switch tube Q1 is grounded, the control end of the first switch tube Q1 is connected to the first end of the second resistor R2, and the second end of the second resistor R2 serves as the control end of the driving unit; the control end of the first switch tube is also grounded through the third resistor R3.

[0113] It should be noted that, in the embodiment provided Fig. 9 In the embodiment, the first switch tube is specifically an NPN transistor. In other embodiments, the first switch tube may be specifically other switch tubes, such as a MOS tube or a field effect tube.

[0114] By dividing the voltage of the first resistor, the second resistor and the third resistor, when a high potential is input to the control terminal of the first switch tube, the switch tube is turned on to realize the conduction of the driving unit. In addition, by limiting the current of the first resistor, the second resistor and the third resistor, when the driving module is turned on, it is prevented that the current passing through the first switch tube is too large, resulting in damage to the first switch tube, and the circuit stability can be improved.

[0115] In another embodiment provided by the present invention, the switch unit includes a second switch tube and a fourth resistor;

[0116] The input end of the second switch tube serves as the input end of the switch unit, the output end of the second switch tube serves as the output end of the switch unit, and the control end of the second switch tube serves as the control end of the switch unit;

[0117] The input end of the second switch tube is also connected to its control end through the fourth resistor.

[0118] When this embodiment is implemented, see Fig. 9 The switch unit includes a second switch tube Q2 and a fourth resistor R4.

[0119] The input end of the second switch tube Q2 serves as the input end of the switch unit, the output end of the second switch tube Q2 serves as the output end of the switch unit, and the control end of the second switch tube Q2 serves as the control end of the switch unit;

[0120] The input end of the second switch tube Q2 is also connected to the control end of the second switch tube Q2 through a fourth resistor R4.

[0121] It should be noted that, in the embodiment provided Fig. 9 In the embodiment, the second switch tube is specifically a MOS tube. In other embodiments, the second switch tube may be specifically other switch tubes, such as a triode or a field effect tube.

[0122] By dividing the voltage between the fourth resistor and the first resistor, when the first switch tube is turned on, the turn-on condition of the first switch tube and the second switch tube can be formed, so that the switch unit is turned on.

[0123] In the specific application of the switch module and the drive module, the first resistor R1 and the second resistor R2 are selected as resistors with a resistance of 4.7K, the third resistor R3 and the fourth resistor R4 are selected as resistors with a resistance of 47K, the power supply voltage of the input end of the switch module is 12V, and the controller outputs a PWM control signal through the control signal output end Heat-con, and controls the conduction or cutoff of the first switch tube Q1 through current limiting by the second resistor R2 and current shunting by the third resistor R3.

[0124] When the first switch tube Q1 is turned on, the 12V supply voltage is divided by the fourth resistor R4 and the first resistor R, and a 1.1V voltage is generated at the control end of the second switch tube Q2, that is, the G pole. At this time, the voltage difference between the control end and the input end of the second switch tube Q2, that is, the GS, is 10.9V. The second switch tube Q2 is turned on, and the 12V supply voltage charges the output capacitor C through the second switch tube Q2 and the inductor L.

[0125] When the first switch tube Q1 is turned off, the 12V voltage is added to the control end of the second switch tube Q2, that is, the G pole, through the fourth resistor R4. At this time, the voltage difference between the control end and the input end of the second switch tube Q2, that is, GS, is 0 volts. The second switch tube Q2 is turned off, and the output capacitor is charged through the freewheeling function of the inductor.

[0126] In another embodiment provided by the present invention, the voltage stabilizing unit specifically includes a voltage stabilizing tube;

[0127] The anode of the voltage regulator tube serves as the input end of the voltage regulator unit, and the cathode of the voltage regulator tube serves as the output end of the voltage regulator unit.

[0128] In the specific implementation of this embodiment, the controller is working in a specific manner. Fig. 9 , the voltage stabilizing unit specifically includes a voltage stabilizing tube D;

[0129] The anode of the voltage regulator tube D serves as the input terminal IN3 of the voltage regulator unit, and the cathode of the voltage regulator tube D serves as the output terminal OUT3 of the voltage regulator unit.

[0130] The voltage regulator tube can ensure the stability of the voltage output by the switch module, avoid the influence of voltage mutation on the working performance of the heating wire, and maintain the stability of the heating work.

[0131] In another embodiment of the present invention, the voltage stabilizing unit further includes a third switch tube and a fifth resistor:

[0132] The input end of the third switch tube is connected to the anode of the voltage regulator tube, the output end of the third switch tube is connected to the cathode of the voltage regulator tube, and the control end of the third switch tube is connected to the control end of the switch unit through the fifth resistor.

[0133] When this embodiment is implemented, see Fig. 9The voltage stabilizing unit further includes a third switch tube Q3 and a fifth resistor R5:

[0134] The input end of the third switch tube Q3 is connected to the anode of the voltage regulator tube D, the output end of the third switch tube Q3 is connected to the cathode of the voltage regulator tube D, and the control end of the third switch tube Q3 is connected to the control end CON1 of the switch unit through the fifth resistor R5.

[0135] It should be noted that, in the embodiment provided Fig. 9 In the embodiment, the third switch tube is specifically a MOS tube. In other embodiments, the third switch tube may be specifically other switch tubes, such as a triode or a field effect tube.

[0136] When the first switch tube Q1 is turned on, the 12V supply voltage is divided by the fourth resistor R4 and the first resistor R, and a 1.1V voltage is generated at the control end of the second switch tube Q2, that is, the G pole. At this time, the voltage difference between the control end and the input end, that is, the GS, of the second switch tube Q2 is 10.9V, and the second switch tube Q2 is turned on. At the same time, the 1.1V voltage is added to the control end, that is, the G pole, of the third switch tube Q3 through the fifth resistor R5. At this time, the voltage difference between the control end and the input end, that is, the GS, of the third switch tube Q3 is 1.1V, and the third switch tube Q3 is turned off. The second switch tube Q2 is turned on, and the 12V supply voltage charges the output capacitor C through the second switch tube Q2 and the inductor L.

[0137] When N1 is turned on, 12V is divided by R12 and R13, and a 1.1V voltage is generated at the G pole of MOS1. At this time, the GS voltage difference of MOS1 is 10.9V, and the MOS1 switch is turned on. At the same time, the 1.1V voltage is added to the G pole of MOS2 through R16. At this time, the GS voltage difference of MOS2 is 1.1V, and the MOS2 switch is turned off. When the MOS1 switch is turned on, the 12V power supply charges the capacitor E2 through the MOS1 switch and the L1 inductor.

[0138] When the first switch tube Q1 is turned off, the 12V voltage is added to the control end, i.e., the G pole, of the second switch tube Q2 through the fourth resistor R4, and is added to the control end, i.e., the G pole, of the third switch tube Q3 through the fifth resistor. At this time, the voltage difference between the control end and the input end, i.e., the GS, of the second switch tube Q2 is 0 volts, the second switch tube Q2 is turned off, the voltage difference between the control end and the input end, i.e., the GS, of the third switch tube Q3 is 12V, the third switch tube Q3 is turned on, and the output capacitor is charged through the freewheeling function of the inductor.

[0139] The third switch tube Q3 and the fifth resistor R5 are designed to replace the voltage regulator tube D. The energy loss generated when the current flows through the voltage regulator tube D when the second switch tube Q2 is turned on or off can be reduced, thereby improving the energy utilization efficiency of the circuit.

[0140] In another embodiment provided by the present invention, the temperature acquisition module specifically includes a thermistor, a sixth resistor, a seventh resistor and a first capacitor;

[0141] The thermistor is installed close to the heating wire;

[0142] The first end of the sixth resistor is used to connect to the power supply end, and the second end of the sixth resistor is grounded through the thermistor;

[0143] The second end of the sixth resistor is also connected to the first end of the seventh resistor, and the second end of the seventh resistor is connected to the temperature collection end of the controller;

[0144] The second end of the seventh resistor is also grounded through the first capacitor.

[0145] When this embodiment is implemented, see Fig.10 , is a schematic diagram of the structure of a temperature acquisition module provided in an embodiment of the present invention; the temperature acquisition module specifically includes a thermistor RTC, a sixth resistor R6, a seventh resistor R7 and a first capacitor C1;

[0146] The thermistor RTC is installed close to the heating wire T and is used to detect the temperature of the heating wire. The resistance value of the thermistor changes with the temperature.

[0147] It should be noted that the thermistor RTC may be a positive temperature coefficient thermistor or a negative temperature coefficient thermistor.

[0148] A first end of the sixth resistor R6 is used to connect to the power supply terminal VCC2, and a second end of the sixth resistor R6 is grounded via the thermistor RTC;

[0149] The second end of the sixth resistor R6 is also connected to the first end of the seventh resistor R7, and the second end of the seventh resistor R7 is connected to the temperature collection terminal AD of the controller; the second end of the seventh resistor R7 is also grounded through the first capacitor C1.

[0150] By dividing the voltage between the sixth resistor and the thermistor and detecting the voltage at the output end of the temperature acquisition module, the voltage dividing relationship between the thermistor and the sixth resistor can be determined, and then the resistance value of the thermistor can be determined by the resistance value of the sixth resistor. The specific problem of the thermistor can be determined by the resistance value of the thermistor, and then the temperature of the heating wire can be obtained.

[0151] The controller can accurately calculate the temperature of the heating wire according to the circuit parameters of the specific temperature acquisition module and the voltage intensity collected by the temperature acquisition terminal.

[0152] The above is a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several improvements and modifications without departing from the principle of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A refrigerator heating wire power modulation circuit, characterized in that: include: The controller is used to output a control signal to control the operation of the heating wire of the refrigerator: A switch module, used for outputting a power supply voltage of the heating wire according to a control signal output by the controller; An output capacitor, used to receive the power supply voltage output by the switch module for charging, and to supply power to the heating wire by discharging; The input end of the switch module is used to connect to the power supply end, the control end of the switch module is connected to the output end of the control signal of the controller, and the output end of the switch module is connected to the power supply end of the heating wire; the first end of the output capacitor is connected to the output end of the switch module, and the second end of the output capacitor is grounded.

2. The refrigerator heating wire power modulation circuit according to claim 1, characterized in that: The circuit also includes a temperature acquisition module; The controller collects the temperature of the heating wire through the temperature collection module, and outputs a control signal to the switch module according to the collected temperature.

3. The refrigerator heating wire power modulation circuit according to claim 1, characterized in that: The circuit also includes an inductor: The first end of the output capacitor is connected to the output end of the switch module, specifically: The first end of the output capacitor is connected to the output end of the switch module through the inductor.

4. The refrigerator heating wire power modulation circuit according to claim 1, characterized in that: The switch module specifically includes a driving unit and a switch unit; The driving unit is used to drive the switch unit; The switch unit is used to control the switch module to be turned on or off; The input end of the switch unit serves as the input end of the switch module, and the output end of the switch unit serves as the output end of the switch module; The control end of the switch unit is connected to the input end of the drive unit, the output end of the drive unit is grounded, and the control end of the drive unit serves as the control end of the switch module.

5. The refrigerator heating wire power modulation circuit as claimed in claim 4, characterized in that: The switch module also includes a voltage stabilizing unit; The voltage stabilizing unit is used to stabilize the output end of the switch module; The output end of the switch unit is connected to the input end of the voltage stabilizing unit, and the output end of the voltage stabilizing unit is grounded.

6. The refrigerator heating wire power modulation circuit according to claim 4, characterized in that: The driving unit includes a first switch tube, a first resistor, a second resistor and a third resistor; The first end of the first resistor serves as the input end of the driving unit, the second end of the first resistor is connected to the input end of the first switch tube, the second end of the first switch tube is grounded, the control end of the first switch tube is connected to the first end of the second resistor, and the second end of the second resistor serves as the control end of the driving unit; The control end of the first switch tube is also grounded through the third resistor.

7. The refrigerator heating wire power modulation circuit according to claim 4, characterized in that: The switch unit includes a second switch tube and a fourth resistor; The input end of the second switch tube serves as the input end of the switch unit, the output end of the second switch tube serves as the output end of the switch unit, and the control end of the second switch tube serves as the control end of the switch unit; The input end of the second switch tube is also connected to its control end through the fourth resistor.

8. The refrigerator heating wire power modulation circuit according to claim 5, characterized in that: The voltage stabilizing unit specifically includes a voltage stabilizing tube; The anode of the voltage regulator tube serves as the input end of the voltage regulator unit, and the cathode of the voltage regulator tube serves as the output end of the voltage regulator unit.

9. The refrigerator heating wire power modulation circuit according to claim 8, characterized in that: The voltage stabilizing unit further includes a third switch tube and a fifth resistor: The input end of the third switch tube is connected to the anode of the voltage regulator tube, the output end of the third switch tube is connected to the cathode of the voltage regulator tube, and the control end of the third switch tube is connected to the control end of the switch unit through the fifth resistor.

10. The refrigerator heating wire power modulation circuit according to claim 2, characterized in that: The temperature acquisition module specifically includes a thermistor, a sixth resistor, a seventh resistor and a first capacitor; The thermistor is installed close to the heating wire; The first end of the sixth resistor is used to connect to the power supply end, and the second end of the sixth resistor is grounded through the thermistor; The second end of the sixth resistor is also connected to the first end of the seventh resistor, and the second end of the seventh resistor is connected to the temperature collection end of the controller; The second end of the seventh resistor is also grounded through the first capacitor.

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