Safe low-voltage load distribution circuit of clothes airing machine and load power supply system

Abstract

The utility model discloses a safe low-voltage load distribution circuit of a clothes airing machine and a load power supply system. The safe low-voltage load distribution circuit comprises a safe low-voltage conversion circuit, an MCU controller, a first load distribution module, a second load distribution module and a third load distribution module, the safe low-voltage conversion circuit outputs direct-current safe low voltage; a first power supply module of the first load distribution module comprises a boosting constant-current chip, and the boosting constant-current chip boosts a direct-current safe low voltage and outputs the direct-current safe low voltage to a load through a first short-circuit protection module; a second power supply module of the second load outputs to the load through a second short-circuit protection module; a third power supply module of the third load distribution module outputs to the load through a third short-circuit protection module and a fourth short-circuit protection module; the system has the advantages that the clothes airing machine load is powered by the human body safety voltage, independent short-circuit protection of each load distribution module is realized, electric shock and short-circuit fire are avoided, and the power utilization safety coefficient is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of electric clothes drying machine, especially relates to a clothes drying machine safety low-voltage load distribution circuit and load power supply system for distributing the load of clothes drying machine with safe low voltage and improving the power safety factor of clothes drying machine. BACKGROUND

[0002] The exposed parts of the electric clothes drying machine product, such as the body shell, drying rod and lifting assembly, are usually made of metal material, and the internal body is provided with functional parts such as motor, flat lamp, fan and sterilization lamp, which are generally fixed on the body, and once the functional parts are electrified, the aforementioned exposed parts will be electrified, which will cause a safety hazard of electric shock accident.

[0003] The existing functional parts of the electric clothes drying machine, such as motor, flat lamp, fan and sterilization lamp, are powered by mains, which is 220V alternating current in China. For example, the utility model patent with the authorization announcement number CN208819062U discloses a DC integrated clothes drying machine controller, wherein the load module includes a high-voltage input load, which is directly powered by the power supply. However, the voltage value of 220V mains is much higher than the safe voltage 36V that the human body can withstand, and once the functional parts are electrified, the threat to the personal safety of the user is unimaginable.

[0004] The current safety measures commonly used are to strengthen the insulation strength or increase the electrical distance between the functional parts and the metal exposed parts, and at the same time, a protective grounding wire is arranged on the shell of the product. However, the miniaturization of the overall size of the clothes drying machine product and the concealment of the installation are the inevitable trend of market development, and the increase of insulation strength or electrical distance has become a solution to the "anti-trend". On the other hand, many current electric clothes drying machines are installed on the ceiling or suspended ceiling instead of the balcony lamp, and many commercial housing balcony lamp installation positions do not reserve the grounding wire at the same time. This series of problems make it difficult to effectively solve the safety hazard of functional part load electrification.

[0005] In addition, the functional part load is powered by 220V mains, and since the voltage is high, once the load is short-circuited, the short-circuit current is also large, and the risk of fire of the clothes drying machine is relatively high. UTILITY MODEL CONTENTS

[0006] In view of the fact that the load of the functional components of the existing electric clothes drying machine is powered by 220V AC mains, there is a risk of electric shock accident caused by the electrification of the aforementioned exposed components due to leakage, the problem of large short-circuit current, and the current solution does not adapt to the market development trend of clothes drying machines, the technical problem to be solved by the utility model is to provide a clothes drying machine safety low-voltage load distribution circuit and load power supply system, which distributes the load of the clothes drying machine with safe low voltage, and provides an independent short-circuit protection circuit to improve the power safety factor of the clothes drying machine product.

[0007] The utility model adopts the technical scheme for solving the above technical problem: clothes drying machine safety low-voltage load distribution circuit, including safety low-voltage conversion circuit, and the MCU controller, first load distribution module, second load distribution module and third load distribution module powered by the safety low-voltage conversion circuit;

[0008] The safety low-voltage conversion circuit is used for connecting the mains power supply and outputting the direct-current safety low-voltage;The output port of the MCU controller is connected with the first load distribution module, the second load distribution module and the third load distribution module respectively;

[0009] The first load distribution module is used for connecting and controlling the lighting load, and includes the first power supply module and the first short-circuit protection module;The first power supply module includes a boost constant current chip, which boosts the direct-current safety low-voltage and outputs to the load through the first short-circuit protection module;

[0010] The second load distribution module is used for connecting and controlling the motor load, and includes the second power supply module and the second short-circuit protection module;The second power supply module outputs to the load through the second short-circuit protection module;

[0011] The third load distribution module is used for connecting and controlling the fan and the sterilization load, and includes the third power supply module, the third short-circuit protection module and the fourth short-circuit protection module;The third power supply module outputs to the load through the third short-circuit protection module and the fourth short-circuit protection module.

[0012] The preferred technical scheme for solving the above technical problem of the utility model is that the safety low-voltage conversion circuit is an ACDC converter, and the output direct-current safety low-voltage is 24V;The boost constant current chip boosts the direct-current safety low-voltage to 36V.

[0013] The preferred technical scheme for solving the above technical problem of the utility model is that the first output port of the MCU controller is connected with the E / P port of the boost constant current chip;

[0014] The CS / OVP port of the boost constant current chip is short-circuited with the GATE port, the CS / OVP port is connected with the gate of the first MOS tube through a first resistor, the GATE port is connected with the negative electrode of the second diode, and the positive electrode of the second diode is connected with the gate of the first MOS tube.

[0015] The FB port of the boost constant current chip is output to a load and grounded through a second resistor.

[0016] The preferred technical scheme for solving the above technical problems is that the source of the first MOS tube is grounded, the drain of the first MOS tube is connected with the DC safe low voltage through a first inductor, a node between the first inductor and the DC safe low voltage is grounded through a first polar capacitor, the drain of the first MOS tube is connected with the positive electrode of the first diode, the negative electrode of the first diode is connected with the first short-circuit protection module, a node between the negative electrode of the first diode and the first short-circuit protection module is grounded through a second polar capacitor.

[0017] The preferred technical scheme for solving the above technical problems is that the source of the first MOS tube is grounded, the drain of the first MOS tube is connected with the DC safe low voltage through a first inductor, a node between the first inductor and the DC safe low voltage is grounded through a first polar capacitor, the drain of the first MOS tube is connected with the positive electrode of the first diode, the negative electrode of the first diode is connected with the first short-circuit protection module, a node between the negative electrode of the first diode and the first short-circuit protection module is grounded through a second polar capacitor.

[0018] The preferred technical scheme for solving the above technical problems is that the first short-circuit protection module comprises a second MOS tube and a third triode.

[0019] The source of the second MOS tube is connected with the base of the third triode through a fifth resistor, the source of the second MOS tube is connected with the drain of the second MOS tube through a third resistor, and the gate of the second MOS tube is connected with the drain of the second MOS tube through a fourth resistor.

[0020] The gate of the second MOS tube is connected with the collector of the third triode through a sixth resistor, and the gate of the second MOS tube is connected with the emitter of the third triode through a first capacitor; the base of the third triode is connected with the emitter of the third triode through a seventh resistor.

[0021] A node between the fourth resistor and the first capacitor is connected with the positive electrode of a third diode, and the negative electrode of the third diode is connected with the drain of the second MOS tube.

[0022] The source of the second MOS tube and the emitter of the third triode are output to a load.

[0023] The preferred technical scheme for solving the above technical problems is that the circuit structures of the first short-circuit protection module, the third short-circuit protection module and the fourth short-circuit protection module are same.

[0024] The utility model discloses an optimal technical scheme which is adopted to solve the above technical problem, and the second power supply module includes integrated motor drive chip, and the integrated motor drive chip exports the direct current safety low voltage to load through the second short circuit protection module.

[0025] The first input port of the integrated motor drive chip is connected with the third output port of the MCU controller, and the second input port of the integrated motor drive chip is connected with the output end of the second short circuit protection module.

[0026] The utility model discloses an optimal technical scheme which is adopted to solve the above technical problem, and the second short circuit protection module includes eighth resistance, comparator and AND gate circuit, the negative input end of the comparator is connected with the output end of the integrated motor drive chip through eighth resistance, the positive input end of the comparator is connected with 2.5V direct current power supply, and the output end of the comparator is connected with the second input port of the AND gate circuit.

[0027] The first input port of the AND gate circuit is connected with the second output port of the MCU controller, and the output port of the AND gate circuit is connected with the second input port of the integrated motor drive chip.

[0028] The utility model discloses an optimal technical scheme which is adopted to solve the above technical problem, and the third power supply module includes integrated darlington chip, and the integrated darlington chip exports the direct current safety low voltage to load through the third short circuit protection module and the fourth short circuit protection module respectively.

[0029] The first input port of the integrated darlington chip is connected with the fourth output port of the MCU controller, and the second input port of the integrated darlington chip is connected with the fifth output port of the MCU controller.

[0030] The utility model discloses another technical scheme which is adopted to solve the above technical problem, and the airing machine safety low voltage load power supply system includes filter circuit, rectifier circuit and airing machine safety low voltage load distribution circuit.

[0031] The filter circuit is used for connecting commercial power supply, the rectifier circuit is connected with the filter circuit, and the safety low voltage conversion circuit is connected with the rectifier circuit to convert the commercial power supply after filtering through the filter circuit and rectification through the rectifier circuit and output direct current safety low voltage.

[0032] Compared with the prior art, the advantages of the utility model are: through a set of clothes drying machine safety low voltage load power supply system, the power supply of whole load can be realized to be below 36V of human body safety voltage, that is, through clothes drying machine safety low voltage load distribution circuit, realize by safety low voltage conversion circuit to direct current safety low voltage for clothes drying machine load power supply, connect and control three load distribution modules with MCU controller, break the power distribution mode of high voltage of existing clothes drying machine load power supply, relay low voltage, realize that even if load leakage, voltage of exposed metal part also can not exceed human body safety voltage, avoid the occurrence of electric shock accident.

[0033] In addition, each load distribution module adopts independent short circuit protection circuit, greatly reduces the probability of clothes drying machine fire accident caused by load short circuit, and can realize the shortening of the internal electrical distance of the clothes drying machine, so that the size of the clothes drying machine can be further developed to be small and intensive, which meets the market development trend of intelligent electrical appliances, and achieves two goals at once. BRIEF DESCRIPTION OF DRAWINGS

[0034] The utility model will be described in further detail below in combination with the drawings and preferred embodiments, but those skilled in the art will appreciate that these drawings are only drawn for the purpose of explaining the preferred embodiments and therefore should not be regarded as limiting the scope of the utility model. In addition, unless specifically indicated, the drawings only schematically show the composition or structure of the described objects and can include exaggerated display, and the drawings are not necessarily drawn to scale.

[0035] Figure 1 It is the electrical diagram of clothes drying machine load power supply system of prior art;

[0036] Figure 2 It is the circuit diagram of low voltage part of clothes drying machine load power supply system of prior art;

[0037] Figure 3 It is the electrical diagram of clothes drying machine load power supply system of one preferred embodiment of the utility model;

[0038] Figure 4 It is the general circuit diagram of clothes drying machine safety low voltage load distribution circuit;

[0039] Figure 5 It is the circuit diagram of first load distribution module of clothes drying machine safety low voltage load distribution circuit;

[0040] Figure 6 It is the circuit diagram of first power supply module of clothes drying machine safety low voltage load distribution circuit;

[0041] Figure 7 It is the circuit diagram of first short circuit protection module of clothes drying machine safety low voltage load distribution circuit;

[0042] Figure 8 A circuit diagram of a second load distribution module of a safe low-voltage load distribution circuit for a clothes drying machine;

[0043] Figure 9 A circuit diagram of a third load distribution module of a safe low-voltage load distribution circuit for a clothes drying machine;

[0044] Description of reference numerals:

[0045] Clothes drying machine load power supply system 100, high voltage part 101, low voltage part 102, clothes drying machine safe low voltage load power supply system 200, high voltage part 201, low voltage part 202, clothes drying machine safe low voltage load distribution circuit 300, first load distribution module 301, second load distribution module 302, third load distribution module 303, first power supply module 11, first short circuit protection module 12, second short circuit protection module 22, second power supply module 21, third power supply module 31, third short circuit protection module 32, fourth short circuit protection module 33. DETAILED DESCRIPTION

[0046] The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Those skilled in the art will appreciate that these descriptions are merely illustrative and exemplary and should not be construed as limiting the scope of protection of the present invention.

[0047] In the description of this utility model, it should be noted that the terms "upper," "lower," "front," "back," "left," "right," "inner," and "outer" and the like, indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, or are the directions or positional relationships in which the utility model product is typically placed when in use. These terms are intended solely to facilitate the description of this utility model and simplify the description, and are not intended to indicate or imply that the device or component referred to must have a specific direction, be constructed, or operate in a specific direction. Therefore, they should not be construed as limitations on this utility model. The terms "first" and "second" are used solely to facilitate understanding and have no other directional meanings, and should not be construed as limitations on this utility model.

[0048] like Figure 1 The following figure shows the electrical block diagram of a clothes drying machine load power supply system 100, commonly used in the prior art. The system comprises a high-voltage section 101 and a low-voltage section 102. High-voltage section 101 includes a filter circuit and a rectifier circuit. The filter circuit receives and filters the 220V AC power supply before directly powering loads such as the motor, lighting, fan, and sterilization system. Therefore, these loads are also included in high-voltage section 101.

[0049] The low-voltage section 102 includes a safe low-voltage converter circuit, an MCU controller, and relays. The rectifier circuit converts the AC-to-DC power from the AC mains after filtering by the filter circuit, and then outputs it to the safe low-voltage converter circuit, which converts it to a safe low-voltage DC power supply.

[0050] Combined with Figure 2 As can be seen from the circuit diagram of the low-voltage part 102 shown, the DC safe low voltage output by the safe low-voltage conversion circuit only powers the MCU controller and each relay. The MCU controller controls the operation start and stop of various loads by controlling each relay.

[0051] As can be seen, in the existing clothes drying machine load power supply system 100, since the motor, lighting, fan, and sterilization loads are powered by the high-voltage component 101, if a leakage occurs, the leakage voltage on the exposed parts of the clothes drying machine will be far higher than the human safety voltage, endangering personal safety. Similarly, if a short circuit occurs, the short-circuit current is also very large, which can easily cause the clothes drying machine and its components to catch fire, posing a significant electrical safety hazard.

[0052] like Figure 3 The figure shows a safe low-voltage load power supply system 200 for a clothes drying machine provided in this embodiment, which also includes a high-voltage portion 201 and a low-voltage portion 202. Similar to the existing clothes drying machine load power supply system 100, the high-voltage portion 201 includes a filter circuit and a rectifier circuit. The filter circuit is connected to the 220V AC power supply and performs filtering. The rectifier circuit is connected to the filter circuit and performs AC-to-DC rectification on the filtered 220V AC power supply.

[0053] The low-voltage section 202 includes the clothes drying machine's safe low-voltage load distribution circuit. The safe low-voltage converter circuit is connected to the rectifier circuit to convert the 220V AC power supply, filtered by the filter circuit and rectified by the rectifier circuit, into a safe low-voltage DC output, which serves as the power supply for the clothes drying machine's safe low-voltage load distribution circuit. This circuit supplies power to loads such as the motor, lighting, fan, and sterilization system, and controls their operation and shutdown.

[0054] It can be seen that in the safe low-voltage load power supply system 200 for the clothes drying machine provided in this embodiment, loads such as motors, lighting, fans and sterilization are powered by the low-voltage part 202. Therefore, loads such as motors, lighting, fans and sterilization are included in the low-voltage part 202. Even if leakage occurs, the leakage voltage carried by the exposed part of the clothes drying machine is lower than the safety voltage of the human body and will not cause harm to personal safety. Even if a short circuit occurs, the short-circuit current is very small, and it is difficult to cause a fire accident, thereby effectively improving the electrical safety factor of the clothes drying machine product.

[0055] like Figure 4As shown in the circuit diagram of the clothes drying machine safety low-voltage load distribution circuit 300 provided in the embodiment, the circuit includes a safety low-voltage conversion circuit (not shown in the figure), and an MCU controller, a first load distribution module 301, a second load distribution module 302, and a third load distribution module 303 powered by the safety low-voltage conversion circuit.

[0056] The safety low-voltage conversion circuit is connected to a 220V mains power supply through a rectifier circuit and a filter circuit, and outputs a direct-current safety low voltage. In the embodiment, the safety low-voltage conversion circuit adopts an ACDC converter, and the output direct-current safety low voltage is 24V. The MCU controller has five output ports GPIO, among which the first output port GPIO1 is connected to the first load distribution module 301, the second output port GPIO2 and the third output port GPIO3 are connected to the second load distribution module 302, and the fourth output port GPIO4 and the fifth output port GPIO5 are connected to the third load distribution module 303.

[0057] As shown in the circuit diagram of the clothes drying machine safety low-voltage load distribution circuit 300 provided in the embodiment, the circuit includes a safety low-voltage conversion circuit (not shown in the figure), and an MCU controller, a first load distribution module 301, a second load distribution module 302, and a third load distribution module 303 powered by the safety low-voltage conversion circuit. Figures 5 to 7 The first load distribution module 301 is used for connecting and controlling the lighting load CN3, and includes a first power supply module 11 and a first short-circuit protection module 12. In the embodiment, the first power supply module 11 includes a boost constant-current chip U1, which boosts the direct-current safety low voltage and outputs it to the lighting load CN3 through the first short-circuit protection module 12.

[0058] In the embodiment, the boost constant-current chip U1 boosts the direct-current safety low voltage 24V to 36V. Specifically, the first output port GPIO1 of the MCU controller is connected to the E / P port of the boost constant-current chip U1. The CS / OVP port of the boost constant-current chip U1 is short-circuited with the GATE port, the CS / OVP port is connected to the gate electrode G of the first MOS tube Q1 through the first resistor R1, the GATE port is connected to the negative electrode of the second diode D2, and the positive electrode of the second diode D2 is connected to the gate electrode G of the first MOS tube Q1, so that the first resistor R1 is connected in parallel between the positive and negative electrodes of the second diode D2.

[0059] The VCC port of the boost constant-current chip U1 is connected to a 5V direct-current power supply, the GND port is grounded, the FB port is output to the lighting load CN3 and grounded through the second resistor R2, the non-grounded end of the second resistor R2 is connected to a node between the FB port and the lighting load CN3, and is located at the front end of the first short-circuit protection module 12, and the grounded end of the second resistor R2 is grounded.

[0060] The source electrode S of the first MOS tube Q1 is grounded, and the drain electrode D of the first MOS tube is connected to the direct-current safety low voltage 24V through the first inductor L1. The node between the first inductor L1 and the direct-current safety low voltage 24V is grounded through the first polarized capacitor AEC1, wherein the negative electrode of the first polarized capacitor AEC1 is grounded.

[0061] The drain D of the first MOS Q1 is connected to the anode of the first diode D1, the cathode of the first diode D1 is connected to the first short-circuit protection module 12, and the node between the cathode of the first diode D1 and the first short-circuit protection module 12 is grounded through the second polarized capacitor AEC2, wherein the negative electrode of the second polarized capacitor AEC2 is grounded.

[0062] On the one hand, the first power supply module 11 boosts the direct-current safe low voltage 24V to 36V at the equipotential position of the cathode of the first diode D1 and the anode of the second polarized capacitor AEC2, and supplies power to the lighting load CN3 after passing through the first short-circuit protection module 12. On the other hand, the first output port GPIO1 of the MCU controller can realize the control function of turning on and off the lighting load, and when the first output port GPIO1 is at low level, the lighting is turned off, and when the first output port GPIO1 is at high level, the lighting is turned on.

[0063] As shown in Figure 7 The first short-circuit protection module 12 includes a second MOS Q2 and a third triode Q3. The source of the second MOS Q2 is connected to the base of the third triode Q3 through the fifth resistor R5, the source of the second MOS Q2 is connected to the drain of the second MOS through the third resistor R3, and the gate of the second MOS Q2 is connected to the drain of the second MOS Q2 through the fourth resistor R4.

[0064] The gate of the second MOS Q2 is connected to the collector of the third triode Q3 through the sixth resistor R6, the gate of the second MOS Q2 is connected to the emitter of the third triode Q3 through the first capacitor C1, and the base of the third triode Q3 is connected to the emitter of the third triode Q3 through the seventh resistor R7.

[0065] The node between the fourth resistor R4 and the first capacitor C1 is connected to the anode of the third diode D3, and the cathode of the third diode D3 is connected to the drain of the second MOS Q2. The source of the second MOS Q2 and the emitter of the third triode Q3 are output to the lighting load CN3.

[0066] The working principle of the first short-circuit protection module 12 is that, since the resistance value of the second resistor R2 is usually small, when the lighting load is short-circuited, the current flowing through the second resistor R2 is very large, which can easily cause the second resistor R2 to burn out and catch fire. After the introduction of the first short-circuit protection module 12, when the lighting load is short-circuited, there is no voltage difference between the base and the emitter of the third triode Q3, the third triode Q3 is disconnected, and at the same time the second MOS Q2 is disconnected, and the 36V voltage is grounded through the third resistor R3, thereby playing a role in short-circuit protection. After the short-circuit fault is eliminated, the second MOS Q2 and the third triode Q3 return to normal.

[0067] As shown in Figure 8As shown, the second load distribution module 302 is used for connecting and controlling the motor load CN1, and includes a second power supply module 21 and a second short-circuit protection module 22. The second power supply module 21 is output to the motor load CN1 through the second short-circuit protection module 22.

[0068] The second power supply module 21 includes an integrated motor drive chip U3, which outputs the direct-current safe low voltage 24V to the motor load CN1 through the second short-circuit protection module 22. The first input port IN1 of the integrated motor drive chip U3 is connected to the third output port GPIO3 of the MCU controller, and the second input port IN2 of the integrated motor drive chip U3 is connected to the output end of the second short-circuit protection module 22.

[0069] On the one hand, the second power supply module 21 supplies the motor load CN1 with the direct-current safe low voltage 24V through the integrated motor drive chip U3 and the second short-circuit protection module 22. On the other hand, the second output port GPIO2 and the third output port GPIO3 of the MCU controller can realize the control functions of starting and stopping and forward and reverse rotation of the motor load CN1. In the embodiment, specifically:

[0070] ①When the third output port GPIO3 is at high level and the second output port GPIO2 is at PWM waveform, the motor rotates forward;

[0071] ②When the third output port GPIO3 is at low level and the second output port GPIO2 is at PWM waveform, the motor rotates reversely;

[0072] ③When the second output port GPIO2 is at low level, no matter whether the third output port GPIO3 is at high level or low level, the motor stops running.

[0073] As shown in Figure 8 The second short-circuit protection module 22 includes an eighth resistor R8, a comparator IC1A and an AND gate circuit U4. The negative input end of the comparator IC1A is connected to the output end OUT2 of the integrated motor drive chip U3 through the eighth resistor R8, the positive input end of the comparator IC1A is connected to a 2.5V direct-current power supply, and the output end of the comparator IC1A is connected to the second input port (pin 2) of the AND gate circuit U4.

[0074] The first input port (pin 1) of the AND gate circuit U4 is connected to the second output port GPIO2 of the MCU controller, and the output port (pin 4) of the AND gate circuit U4 is connected to the second input port IN2 of the integrated motor drive chip U3.

[0075] The working principle of the second short-circuit protection module 22 is that when the motor load CN1 is short-circuited, the eighth resistor R8 acts as a sampling resistor, and its voltage increases sharply. When the voltage exceeds the reference voltage 2.5V of the comparator IC1A, the comparator IC1A outputs a low level. At this time, whether the second output port GPIO2 of the MCU controller is high or low, the output end of the AND gate circuit U4 is low. Therefore, the second input port IN2 of the integrated motor drive chip U3 inputs a low level, thereby disconnecting the motor load CN1, and playing a short-circuit protection role in a hardware manner, and the response speed is fast.

[0076] As shown in Figure 9 The third load distribution module 303 is used for connecting and controlling the fan load CN2 and the sterilization load CN4, and includes a third power supply module 31, a third short-circuit protection module 32, and a fourth short-circuit protection module 33. The third power supply module 31 outputs to the fan load CN2 through the third short-circuit protection module 32, and outputs to the sterilization load CN4 through the fourth short-circuit protection module 33.

[0077] The third power supply module 31 includes an integrated Darlington chip U2. The integrated Darlington chip U2 outputs the direct-current safe low voltage 24V to the fan load CN2 and the sterilization load CN4 through the third short-circuit protection module 32 and the fourth short-circuit protection module 33, respectively. The first input port IN1 of the integrated Darlington chip U2 is connected to the fourth output port GPIO4 of the MCU controller, and the second input port IN2 of the integrated Darlington chip U2 is connected to the fifth output port GPIO5 of the MCU controller.

[0078] On the one hand, the third power supply module 31 supplies the fan load CN2 and the sterilization load CN4 with the direct-current safe low voltage 24V through the integrated Darlington chip U2. On the other hand, the fourth output port GPIO4 and the fifth output port GPIO5 of the MCU controller realize the control function of opening and closing the fan load CN2 and the sterilization load CN4. In the embodiment, specifically:

[0079] ①When the fourth output port GPIO4 is low, the fan is closed, and when it is high, the fan is opened;

[0080] ②When the fifth output port GPIO5 is low, the sterilization lamp is closed, and when it is high, the sterilization lamp is opened;

[0081] In the embodiment, the circuit structures of the first short-circuit protection module 12, the third short-circuit protection module 32, and the fourth short-circuit protection module 33 are the same, so the circuit structures and working principles of the third short-circuit protection module 32 and the fourth short-circuit protection module 33 are not repeated here.

[0082] The utility model discloses a set of clothes drying machine safety low voltage load power supply system, can realize the power supply of whole load is all in the human body safety voltage 36V below, that is, through clothes drying machine safety low voltage load distribution circuit, realizes by safety low voltage conversion circuit with direct current safety low voltage for clothes drying machine load power supply, is connected with MCU controller and controls three load distribution module simultaneously, breaks the power distribution mode of existing clothes drying machine load power supply high voltage, relay low voltage. Therefore, realize the voltage of the exposed metal part of the vertical load leakage also does not exceed the human body safety voltage, avoid the occurrence of the electric shock accident.

[0083] In addition, each load distribution module adopts the short circuit protection circuit independent of each other, greatly reduces the clothes drying machine fire accident probability caused by load short circuit, can realize the shortening of clothes drying machine internal electrical distance simultaneously, makes the size of clothes drying machine can further to small, intensive development, meets the market development trend of intelligent electrical appliances, hits two birds with one stone.

[0084] It should be noted that similar reference numerals refer to similar items throughout the various figures, so once an item is defined in one figure, it can not be further defined and explained in subsequent figures.

[0085] The above clothes drying machine safety low voltage load distribution circuit and load power supply system are introduced, and the principle and implementation mode of the utility model are described by applying specific examples in the paper, and the above embodiment is only used for helping to understand the utility model and core idea. It should be pointed out that for ordinary skilled person in the art, on the premise of not departing from the principle of the utility model, the utility model can be improved and modified in several ways, and these improvements and modifications also fall within the protection scope of the utility model claims.

Claims

1. The safe low-voltage load distribution circuit of the clothes drying machine is characterized by: It includes a safe low voltage conversion circuit, and an MCU controller, a first load distribution module, a second load distribution module and a third load distribution module powered by the safe low voltage conversion circuit; The safe low voltage conversion circuit is used to connect to the mains power supply and output a DC safe low voltage; the output port of the MCU controller is respectively connected to the first load distribution module, the second load distribution module and the third load distribution module; The first load distribution module is used to connect and control the lighting load, including a first power supply module and a first short-circuit protection module; the first power supply module includes a boost constant current chip, which boosts the DC safety low voltage and outputs it to the load through the first short-circuit protection module; The second load distribution module is used to connect and control the motor load, and includes a second power supply module and a second short-circuit protection module; the second power supply module outputs to the load through the second short-circuit protection module; The third load distribution module is used to connect and control the fan and the sterilization load, and includes a third power supply module, a third short-circuit protection module and a fourth short-circuit protection module; The third power supply module is output to the load via the third short-circuit protection module and the fourth short-circuit protection module.

2. The safe low-voltage load distribution circuit for clothes drying machine according to claim 1, characterized in that: The safe low voltage conversion circuit is an ACDC converter, and the output DC safe low voltage is 24V; the boost constant current chip boosts the DC safe low voltage to 36V.

3. The safe low-voltage load distribution circuit for clothes drying machine according to claim 1, characterized in that: The first output port of the MCU controller is connected to the E / P port of the boost constant current chip; The CS / OVP port and the GATE port of the boost constant current chip are short-circuited, the CS / OVP port is connected to the gate of the first MOS tube via a first resistor, the GATE port is connected to the cathode of the second diode, and the anode of the second diode is connected to the gate of the first MOS tube; The FB port of the boost constant current chip is output to the load and is grounded through a second resistor.

4. The safe low-voltage load distribution circuit for clothes drying machine according to claim 3, characterized in that: The source of the first MOS transistor is grounded; the drain of the first MOS transistor is connected to the DC safety low voltage through a first inductor, and the node between the first inductor and the DC safety low voltage is grounded through a first polarized capacitor; The drain of the first MOS tube is connected to the anode of the first diode, and the cathode of the first diode is connected to the first short-circuit protection module; the node between the cathode of the first diode and the first short-circuit protection module is grounded through a second polarized capacitor.

5. The safe low-voltage load distribution circuit for clothes drying machine according to claim 1, characterized in that: The first short-circuit protection module includes a second MOS tube and a third transistor; The source of the second MOS transistor is connected to the base of the third transistor through a fifth resistor, the source of the second MOS transistor is connected to the drain of the second MOS transistor through a third resistor, and the gate of the second MOS transistor is connected to the drain of the second MOS transistor through a fourth resistor; The gate of the second MOS transistor is connected to the collector of the third transistor via a sixth resistor, and the gate of the second MOS transistor is connected to the emitter of the third transistor via a first capacitor; the base of the third transistor is connected to the emitter of the third transistor via a seventh resistor; The node between the fourth resistor and the first capacitor is connected to the anode of the third diode, and the cathode of the third diode is connected to the drain of the second MOS transistor; The source of the second MOS transistor and the emitter of the third transistor are output to a load.

6. The safe low-voltage load distribution circuit for clothes drying machine according to claim 1, characterized in that: The first short-circuit protection module, the third short-circuit protection module, and the fourth short-circuit protection module have the same circuit structure.

7. The safe low-voltage load distribution circuit for clothes drying machine according to claim 1, characterized in that: The second power supply module includes an integrated motor drive chip, and the integrated motor drive chip outputs the DC safe low voltage to the load through the second short-circuit protection module; The first input port of the integrated motor driver chip is connected to the third output port of the MCU controller, and the second input port of the integrated motor driver chip is connected to the output end of the second short-circuit protection module.

8. The safe low-voltage load distribution circuit for clothes drying machine according to claim 7, characterized in that: The second short-circuit protection module includes an eighth resistor, a comparator, and an AND gate circuit; the negative input terminal of the comparator is connected to the output terminal of the integrated motor driver chip through the eighth resistor, the positive input terminal of the comparator is connected to a 2.5V DC power supply, and the output terminal of the comparator is connected to the second input port of the AND gate circuit; The first input port of the AND gate circuit is connected to the second output port of the MCU controller, and the output port of the AND gate circuit is connected to the second input port of the integrated motor driver chip.

9. The safe low-voltage load distribution circuit for clothes drying machine according to claim 1, characterized in that: The third power supply module includes an integrated Darlington chip, and the integrated Darlington chip outputs the DC safe low voltage to the load via the third short-circuit protection module and the fourth short-circuit protection module respectively; The first input port of the integrated Darlington chip is connected to the fourth output port of the MCU controller, and the second input port of the integrated Darlington chip is connected to the fifth output port of the MCU controller.

10. The safe low-voltage load power supply system for clothes drying machine is characterized by: It comprises a filter circuit, a rectifier circuit and a safe low-voltage load distribution circuit for a clothes drying machine as claimed in any one of claims 1 to 9; The filtering circuit is used to connect to the mains power supply, the rectifier circuit is connected to the filtering circuit, and the safe low-voltage conversion circuit is connected to the rectifier circuit to convert the mains power supply after filtering by the filtering circuit and rectification by the rectifier circuit to output a DC safe low voltage.

Images