Exhaust fan driving circuit and exhaust fan

Abstract

The utility model discloses an exhaust fan driving circuit and an exhaust fan, and relates to the technical field of exhaust fans, and the exhaust fan driving circuit comprises a rectification module which is used for converting an AC voltage output by a power supply into a DC voltage; the gear control module is used for outputting different control signals to switch operation gears of a motor of the exhaust fan; the driving module is used for driving a motor of the exhaust fan at different operation gears according to the control signal output by the gear control module; the energy storage power supply module is used for supplying power to the gear control module when the power supply is disconnected so as to maintain the operation of the gear control module; and the power supply voltage division module is used for outputting a first voltage signal and a second voltage signal, when the power supply is switched off, the second voltage signal changes, and the gear control module outputs a control signal different from the current control signal so as to switch the operation gear of the motor of the exhaust fan. The exhaust fan provided by the utility model is low in cost, conforms to the existing use habits of a user and can realize gear switching.

Description

TECHNICAL FIELD

[0001] The present application relates to the exhaust fan technical field, especially to an exhaust fan driving circuit and an exhaust fan. BACKGROUND

[0002] The exhaust fan is a common ventilation equipment, mainly used for removing indoor dirty air, adjusting indoor air circulation and improving indoor environment, and is an important ventilation equipment in household equipment.

[0003] In the related art, the exhaust fan has only two states of on and off, that is, only the control function of turning on and off. When having a meeting or taking a nap, the exhaust fan can only be turned off because of its loud noise, but this will affect ventilation. Therefore, multiple gears on the exhaust fan can solve this problem. However, when wiring a general household, only the two-gear line of the exhaust fan switch is involved, and the line for controlling the gears is not arranged after prying the wall, or the wall switch is replaced with a gear switch (such as a rotary knob), or a remote control exhaust fan is purchased. However, the remote control exhaust fan has high cost and the fan with lost remote control, which is more inconsistent with the use habits of ordinary people. CONTENT OF THE INVENTION

[0004] The present application aims to at least solve one of the technical problems in the prior art, and provides an exhaust fan driving circuit and an exhaust fan, which are low in cost, consistent with the existing use habits of users, and can realize gear switching.

[0005] In a first aspect, an exhaust fan driving circuit is provided, comprising a rectifier module, a gear control module, a driving module, an energy storage power supply module and a power supply voltage dividing module, wherein:

[0006] The rectifier module is configured to convert alternating voltage output by a power supply into direct current voltage;

[0007] The gear control module is configured to output a control signal to control the operation of a motor of the exhaust fan, and output different control signals to switch the operating gears of the motor of the exhaust fan;

[0008] The driving module is configured to drive the motor of the exhaust fan in different operating gears according to the control signal output by the gear control module, and the driving module is connected to the gear control module;

[0009] The energy storage power supply module is connected to the gear control module, and is configured to supply power to the gear control module when the power supply is disconnected, so as to maintain the operation of the gear control module;

[0010] The power supply voltage dividing module is configured to divide the direct current voltage output by the rectifier module, and output a first voltage signal and a second voltage signal. When the power supply is connected, the first voltage signal is configured to supply power to the gear control module. When the power supply is disconnected, the second voltage signal changes, and the gear control module outputs a control signal different from the current control signal in response to the change in the second voltage signal, so as to switch the running gear of the motor of the exhaust fan. The input end of the power supply voltage dividing module is connected to the output end of the rectifier module.

[0011] According to the technical scheme of the embodiments of the present application, the following beneficial effects are achieved. The rectifier module is configured to convert the alternating current voltage output by the power supply into a direct current voltage. The output end of the rectifier module is connected to the power supply voltage dividing module. The power supply voltage dividing module is configured to divide the direct current voltage output by the rectifier module into a first voltage signal for supplying power to the gear control module and a second voltage signal for responding to the gear control module. The voltage output stability is improved, and the running stability of the gear control module is enhanced. When the power supply is disconnected, the first voltage signal disappears, and the energy storage power supply module connected to the gear control module supplies power to the gear control module, so as to maintain the running of the gear control module. Since the power supply is disconnected, the second voltage signal changes, i.e. the potential of the second voltage signal decreases. After detecting the change in the second voltage signal, the gear control module starts to output a control signal different from the current control signal. At this time, the driving module connected to the gear switching module drives the motor of the exhaust fan to run at a different running gear based on the control signal different from the current control signal, so as to realize gear shifting of the exhaust fan. This is equivalent to that the user realizes gear shifting when pressing the power button during the running of the exhaust fan. At this time, when the user presses the power button again to connect the power supply, the first voltage signal continuously supplies power to the gear control module, and the exhaust fan continuously runs at the shifted gear, so as to complete the gear shifting operation of the exhaust fan. In this way, the user can realize gear shifting of the exhaust fan by only pressing the switch button without remote control, which conforms to the existing use habit of the user. The driving circuit of the motor of the exhaust fan does not need to increase the remote control circuit to increase the cost. The gear shifting can be realized only by the cooperation of the gear control module and the energy storage power supply module, which greatly reduces the cost of realizing gear shifting of the exhaust fan.

[0012] According to some embodiments of the present application, the energy storage power supply module includes an energy storage capacitor. When the power supply is connected and the first voltage signal supplies power to the gear control module, the first voltage signal simultaneously charges the energy storage capacitor.

[0013] When the power supply is disconnected, the energy storage capacitor supplies power to the gear control module.

[0014] According to some embodiments of the present application, when the power supply is disconnected, during the period in which the energy storage power supply module supplies power to the gear control module, if the power supply is connected again, the first voltage signal supplies power to the gear control module, and the driving module runs at the current running gear. If the power supply is not connected, the gear control module loses power, and the exhaust fan stops running.

[0015] According to some embodiments of the present application, the power supply voltage dividing module comprises a first diode, a first resistor, a second resistor and a third resistor, the power supply voltage dividing module divides the DC voltage output by the rectifier module to output a first voltage signal through the first resistor, divides the DC voltage output by the rectifier module to output a second voltage signal through the second resistor and the third resistor, one end of the first resistor is connected to one end of the first diode, the second resistor and the third resistor are connected to the other end of the first diode, the gear control module is connected to the connection point of the second resistor and the third resistor, and the second voltage signal is the potential of the connection point.

[0016] According to some embodiments of the present application, the gear control module comprises a control chip, the control chip is configured to: when the power supply is disconnected, the potential of the connection point decreases, and the control chip outputs a control signal different from the current control signal after detecting the decrease of the potential of the connection point.

[0017] According to some embodiments of the present application, the power supply voltage dividing module further comprises a voltage stabilizing diode, and the voltage stabilizing diode is used to stabilize the first voltage signal.

[0018] According to some embodiments of the present application, the control signal output by the gear control module comprises a first control signal and a second control signal, the running gears comprise a first running gear corresponding to the first control signal and a second running gear corresponding to the second control signal, when the power supply is disconnected, the control signal output by the gear control module is converted from the first control signal to the second control signal, and the running gear of the exhaust fan is converted from the first running gear to the second running gear.

[0019] According to some embodiments of the present application, the first control signal and the second control signal are pulse signals with different duty cycles.

[0020] According to some embodiments of the present application, the driving module comprises a driving chip and a fourth resistor, the output end of the driving chip is connected to the motor of the exhaust fan, one end of the fourth resistor is connected to the driving chip, and the other end of the fourth resistor is connected to the gear control module.

[0021] In the second aspect, the embodiments of the present application provide an exhaust fan, comprising a power switch and the exhaust fan driving circuit according to any one of the above.

[0022] Other features and advantages of the present application will be set forth in the following description, and in part will become apparent from the description, or can be learned by practice of the present application. The objects and other advantages of the present application will be realized and achieved by means of the structures particularly pointed out in the description and the claims. BRIEF DESCRIPTION OF DRAWINGS

[0023] The accompanying drawings are used to provide further understanding of the technical solutions of the present application and form a part of the specification, and are used to explain the technical solutions of the present application together with the embodiments of the present application, and do not constitute a limitation on the technical solutions of the present application.

[0024] The present application is further described below in conjunction with the accompanying drawings and embodiments.

[0025] Figure 1 is a structural schematic block diagram of an exhaust fan driving circuit provided by an embodiment of the present application;

[0026] Figure 2 is a structural diagram of an exhaust fan driving circuit provided by an embodiment of the present application. DETAILED DESCRIPTION

[0027] This part will describe the specific embodiments of the present application in detail, and the preferred embodiments of the present application are shown in the accompanying drawings, and the role of the drawings is to supplement the description of the text part of the specification, so that people can intuitively and visually understand each technical feature and the overall technical solution of the present application, but it cannot be understood as a limitation on the protection scope of the present application.

[0028] In the description of the present application, it should be understood that the orientation description, such as the orientation or position relationship indicated by up, down, front, back, left, right, etc. is based on the orientation or position relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element indicated must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0029] In the description of the present application, the meaning of several is one or more, and the meaning of multiple is more than two, greater than, less than, more than, etc. are understood as not including the number, and above, below, etc. are understood as including the number. If it is described as first, second, it is only for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features or the sequence of indicated technical features

[0030] In the description of the present application, unless otherwise explicitly limited, the words such as setting, installing, connecting, etc. should be understood in a broad sense, and the person skilled in the art can reasonably determine the specific meaning of the above words in the present application in combination with the specific content of the technical solution.

[0031] The present application is further described below in conjunction with the accompanying drawings and embodiments. Figures 1-2 The present application is further described below in conjunction with the accompanying drawings and embodiments.

[0032] As shown in Figure 1 , Figure 1The exhaust fan driving circuit provided by an embodiment of the present application comprises a rectifier module, a gear control module, a driving module, an energy storage power supply module and a power supply voltage division module.

[0033] The rectifier module is used to convert the alternating voltage output by the power supply into direct current voltage.

[0034] The gear control module is used to output control signals to control the motor of the exhaust fan to operate, and output different control signals to switch the operating gear of the motor of the exhaust fan.

[0035] The driving module is used to drive the motor of the exhaust fan in different operating gears according to the control signals output by the gear control module, and the driving module is connected to the gear control module.

[0036] The energy storage power supply module is connected to the gear control module, and is used to supply power to the gear control module when the power supply is disconnected, so as to maintain the operation of the gear control module.

[0037] The power supply voltage division module is used to divide the direct current voltage output by the rectifier module, and output a first voltage signal and a second voltage signal, when the power supply is powered, the first voltage signal is used to supply power to the gear control module, when the power supply is disconnected, the second voltage signal changes, and the gear control module outputs a control signal different from the current one in response to the change of the second voltage signal, so as to switch the operating gear of the motor of the exhaust fan, and the input end of the power supply voltage division module is connected to the output end of the rectifier module.

[0038] The input end of the rectifier module is connected to the alternating current power supply, for example, the alternating current mains power supply end, after being connected to the alternating current power supply end, the rectifier module can convert the alternating voltage input by the alternating current power supply end into direct current voltage, one end of the rectifier module connected to the alternating current power supply has a live wire end and a zero line end, in an embodiment, one end of the rectifier module connected to the alternating current power supply can be connected to the power switch button as the power input end, the power supply of the rectifier module by the alternating current power supply is controlled by the power switch button, the other end of the rectifier module is connected to the input end of the power supply voltage division module, the rectifier module can convert the alternating voltage input by the alternating current power supply end into direct current voltage, and then supply power to the power supply voltage division module through the input end of the power supply voltage division module.

[0039] In an embodiment, the rectifier module can convert the alternating voltage input by the alternating current power supply end into 24V direct current voltage, and then transmit it to the power supply voltage division module, that is, the input voltage of the power supply voltage division module is 24V.

[0040] The power supply voltage dividing module is configured to divide the direct current voltage output by the rectifier module, and output a first voltage signal and a second voltage signal. The output end of the power supply voltage dividing module outputting the first voltage signal is connected to the gear control module. When the power supply is on, the first voltage signal is used to supply power to the gear control module. When the power supply is off, the first voltage signal disappears, and the gear control module is powered by the energy storage power supply module. That is, the output end of the power supply voltage dividing module outputting the first voltage signal and the energy storage power supply module are both connected to the gear control module, and are used to supply power to the gear control module. The output end of the power supply voltage dividing module outputting the second voltage signal is connected to the gear control module. Unlike the first voltage signal, the second voltage signal is used to switch the response signal of the control signal output by the gear control module. Specifically, when the power supply is on, the second voltage signal changes, and the gear module detects that the second voltage signal is stable in one state. When the power supply is off, the second voltage signal changes, and the gear module detects that the second voltage signal changes, and outputs a control signal different from the current control signal to switch the running gear of the exhaust fan motor.

[0041] The gear control module can output different control signals to switch the running gear of the exhaust fan motor. It can be understood that the gear control module outputs different control signals in response to the change of the second voltage signal. That is, the running gear and the number of the exhaust fan motor correspond to the type and the number of the control signal, and the type and the number of the control signal correspond to the change type and the number of the second voltage signal. Therefore, the type and the number of the running gear of the exhaust fan motor can correspond to the change type and the number of the second voltage signal. For example, when the change type of the second voltage signal includes existence and disappearance, the running gear type of the exhaust fan motor can include one gear and two gears.

[0042] For example, when the power supply is on, the rectifier module converts the alternating voltage input by the alternating current power supply end into direct current voltage, and supplies power to the power supply voltage dividing module through the input end of the power supply voltage dividing module. The power supply voltage dividing module divides the direct current voltage output by the rectifier module, and outputs a first voltage signal and a second voltage signal. The first voltage signal supplies power to the gear switching module, and the second voltage signal is in a first state. When the gear switching module detects that the second voltage signal is in the first state, it outputs a corresponding first control signal. The driving module drives the motor of the exhaust fan in a first running gear according to the first control signal output by the gear control module.

[0043] When the power is off, the voltage input of the power supply voltage dividing module is disconnected, the first voltage signal disappears, the gear control module is powered by the energy storage power supply module so that the gear control module can continuously detect the state of the second voltage signal, the second voltage signal changes to the second state, and the gear switching module outputs the corresponding second control signal when detecting that the second voltage signal is in the second state, and the driving module drives the motor of the exhaust fan in the second operating gear according to the second control signal output by the gear control module;

[0044] After the power is off, during the period when the gear control module is powered by the energy storage power supply module, when the power is turned on again, the energy storage power supply module stops powering the gear control module, the gear switching module is powered by the first voltage signal, the gear switching module continuously outputs the second control signal, and the driving module continuously drives the motor of the exhaust fan in the second operating gear according to the second control signal output by the gear control module, thereby completing the gear shifting of the exhaust fan; if the power is not turned on again during the period when the gear control module is powered by the energy storage power supply module after the power is off, the energy storage power supply module consumes the stored energy, the gear switching module loses power and cannot output the second control signal, and the driving module stops driving the motor of the exhaust fan in the second operating gear, thereby completing the closing of the exhaust fan.

[0045] Therefore, in the embodiment, the exhaust fan has two different gears, the exhaust fan operates in one gear when the power is turned on, and operates in another gear when the power is turned on again during the period when the gear control module is powered by the energy storage power supply module after the power is turned off, thereby realizing the opening, closing and gear shifting functions of the exhaust fan through the switch button. For example, the switch button of the exhaust fan only has the options of opening and closing (one button can control opening and closing, or two buttons can control opening and closing respectively), when the user uses the exhaust fan, after pressing the opening button of the exhaust fan, the power is turned on, the first voltage signal powers the gear control module, and the exhaust fan is opened; after pressing the closing button of the exhaust fan during the operation of the exhaust fan, the opening button of the exhaust fan is not pressed during the period when the gear control module is powered by the energy storage power supply module, and the exhaust fan is closed; after pressing the closing button of the exhaust fan during the operation of the exhaust fan, the opening button of the exhaust fan is pressed during the period when the gear control module is powered by the energy storage power supply module, and the exhaust fan is gear shifted.

[0046] It should be noted that when the power supply is connected again, the state of the second voltage signal changes, and when the gear shifting module detects that the state of the second voltage signal changes, the output control signal does not change, so that the gear control module outputs a control signal different from the current control signal in response to the change of the second voltage signal. The condition can include that the second voltage signal changes when the power supply is disconnected. Therefore, the change of the second voltage signal when the power supply is connected will not cause the gear control module to output a control signal different from the current control signal.

[0047] In the exhaust fan driving circuit provided in some embodiments of the present application, as shown in Figure 2 The energy storage power supply module includes an energy storage capacitor C5. When the power supply is connected and the first voltage signal supplies power to the gear control module, the first voltage signal simultaneously charges the energy storage capacitor C5.

[0048] When the power supply is disconnected, the energy storage capacitor C5 supplies power to the gear control module.

[0049] It can be understood that the energy storage power supply module includes the energy storage capacitor C5, that is, the component for energy storage and power supply in the energy storage power supply module is the energy storage capacitor C5, and the two ends of the energy storage capacitor C5 are connected to the power input end of the gear control module for supplying power to the gear control module. In addition, the output end of the power supply voltage dividing module outputting the first voltage signal is connected to the gear control module, that is, the output end of the power supply voltage dividing module outputting the first voltage signal is connected to the positive and negative poles of the power input end of the gear control module, respectively. The output end of the power supply voltage dividing module outputting the first voltage signal and the two ends of the energy storage capacitor C5 are both connected to the positive and negative poles of the power input end of the gear control module. In an embodiment, the two ends of the energy storage capacitor C5 can be connected to the connection points of the output end of the power supply voltage dividing module outputting the first voltage signal and the positive and negative poles of the power input end of the gear control module. The two power input ends can be in parallel to facilitate quick switching of power supply.

[0050] Specifically, when the power supply is connected, the first voltage signal output by the power supply voltage dividing module supplies power to the gear control module. At this time, since the two ends of the energy storage capacitor C5 are connected to the connection points of the output end of the power supply voltage dividing module outputting the first voltage signal and the positive and negative poles of the power input end of the gear control module, the first voltage signal output by the power supply voltage dividing module simultaneously charges the energy storage capacitor C5.

[0051] When the power supply is disconnected, the first voltage signal output by the power supply voltage dividing module disappears. At this time, in order to maintain the operation of the gear control module, it is necessary to ensure the power input to the gear control module. Therefore, at the moment when the first voltage signal output by the power supply voltage dividing module disappears, the energy storage capacitor C5 supplies power to the gear control module.

[0052] It can be understood that, during the period of time when the gear control module is powered by the energy storage capacitor C5 after the power is disconnected, if the power is connected again, the gear switching module continuously outputs the second control signal, and the driving module continuously drives the motor of the exhaust fan at the second running gear according to the second control signal output by the gear control module, so as to complete the gear shifting of the exhaust fan. If the power is not connected again, after the energy stored in the energy storage capacitor C5 is consumed, the gear switching module loses power and cannot output the second control signal, and the driving module stops driving the motor of the exhaust fan at the second running gear, so as to complete the closing of the exhaust fan. Therefore, the discharge capacity of the energy storage capacitor C5 determines the gear shifting response time of the exhaust fan. For example, if the discharge capacity of the energy storage capacitor C5 can continuously power the gear control module for 1s, if the power is connected again within 1s, the gear shifting of the exhaust fan is realized, and if the power is not connected again within 1s, the closing of the exhaust fan is realized. Similarly, if the discharge capacity of the energy storage capacitor C5 can continuously power the gear control module for 2s, if the power is connected again within 2s, the gear shifting of the exhaust fan is realized, and if the power is not connected again within 2s, the closing of the exhaust fan is realized. The capacity of the energy storage capacitor C5 can be determined by the use of the exhaust fan.

[0053] In an embodiment, the energy storage capacitor C5 can be a 220 UF / 10V energy storage capacitor.

[0054] In the exhaust fan driving circuit provided in some embodiments of the present application, when the power is disconnected, if the power is reconnected during the period of time when the energy storage power supply module powers the gear control module, the first voltage division signal powers the gear control module, and the driving module operates at the current running gear. If the power is not connected, the gear control module loses power and the exhaust fan stops running.

[0055] It can be understood that, during the period of time when the gear control module is powered by the energy storage power supply module after the power is disconnected, if the energy storage power supply module includes the energy storage capacitor C5, the period of time when the gear control module is powered by the energy storage power supply module is the discharge time of the energy storage capacitor C5, and if the power is reconnected to power the gear control module.

[0056] When the power is disconnected, if the power is reconnected during the period of time when the energy storage power supply module powers the gear control module, the power voltage division module will re-output the first voltage division signal to power the gear control module, and the power supply of the gear control module by the energy storage power supply module stops. That is, only one of the power supply or the energy storage power supply module can power the gear control module at the same time. At this time, the power voltage division module will also re-output the second voltage division signal, that is, the second voltage division signal changes again. However, because the second voltage division signal changes at this time is when the power is connected, the gear control module will not change the output control signal, but will continuously output the same control signal as the current one, so that the driving module operates at the current running gear.

[0057] If the power supply is not reconnected, and the power stored in the energy storage power supply is consumed, neither the power supply nor the energy storage power supply can supply power to the gear control module, the gear control module loses power, the gear control module stops outputting the control signal, and the second voltage signal does not change, that is, the second voltage signal does not change before the power stored in the energy storage power supply is consumed, and the driving module stops driving the motor of the exhaust fan after failing to receive the control signal output by the gear control module.

[0058] It can be predicted that when the power supply is disconnected, if the power supply is not reconnected, the gear control module loses power and stops outputting the control signal; when the gear control module is about to lose power and stop outputting the control signal, the control signal output by the gear control module is the output signal after gear shifting, that is, after the second voltage signal changes when the power supply is disconnected, the gear control module outputs different control signals in response to the change of the second voltage signal; after the gear control module completely loses power and stops outputting the control signal, if the gear control module memorizes the current output state, after the gear control module is powered on again, the control signal output by the gear control module is still the control signal after gear shifting, and the exhaust fan operates at the gear after gear shifting, which does not conform to the normal use logic of the exhaust fan. Normally, the exhaust fan should operate at the same gear every time it is turned on again, because the use environment of the exhaust fan is relatively fixed, and the user's demand when normally using the exhaust fan is also relatively fixed. The gear shifting demand for the exhaust fan is usually because the exhaust capacity and motor noise of the exhaust fan will change after gear shifting, which is different from the normal use state of the exhaust fan.

[0059] Therefore, after the gear control module completely loses power and stops outputting the control signal, the gear control module will be reset, so that after the gear control module is powered on again, the control signal output by the gear control module is the initial control signal before gear shifting.

[0060] In an embodiment, the gear control module can also be configured to memorize the current output state after the gear control module completely loses power and stops outputting the control signal, so that after the gear control module is powered on again, the control signal output by the gear control module is still the control signal after gear shifting.

[0061] In the exhaust fan driving circuit provided in some embodiments of the present application, as shown in Figure 2As shown, the power supply voltage dividing module includes a first diode D1, a first resistor R5, a second resistor R6 and a third resistor R7. The power supply voltage dividing module divides the DC voltage output by the rectifier module to output a first voltage signal through the first resistor R5, and divides the DC voltage output by the rectifier module to output a second voltage signal through the second resistor R6 and the third resistor R7. One end of the first resistor R5 is connected to one end of the first diode D1, and the second resistor R6 and the third resistor R7 are connected to the other end of the first diode D1. The gear control module is connected to the connection point of the second resistor R6 and the third resistor R7, and the second voltage signal is the potential of the connection point.

[0062] Specifically, a sub-voltage dividing network is formed between the second resistor R6 and the third resistor R7, and another sub-voltage dividing network is formed between the equivalent resistance of the second resistor R6 and the third resistor R7 and the first resistor R5. The input ends of the two sub-voltage dividing networks, i.e. the input end of the power supply voltage dividing module, are connected to the output end of the rectifier module. The second resistor R6 is the resistor close to the input end of the power supply voltage dividing module. After the DC voltage output by the rectifier module is output to the input end of the power supply voltage dividing module, the power supply voltage dividing module first divides the DC voltage output by the rectifier module by the sub-voltage dividing network formed between the equivalent resistance of the second resistor R6 and the third resistor R7 and the first resistor R5. The first resistor R5 obtains a first divided voltage, and the equivalent resistance of the second resistor R6 and the third resistor R7 obtains a second divided voltage. Then, the second resistor R6 and the third resistor R7 divide the second divided voltage, so that the second resistor R6 obtains a third divided voltage and the third resistor R7 obtains a fourth divided voltage.

[0063] One end of the first resistor R5 is connected to one end of the first diode D1, which can be used for overvoltage protection. The other end of the first diode D1 is connected to the second resistor R6, and the other end of the first diode D1 is also connected to the input end of the power supply voltage dividing module. That is, the input end of the power supply voltage dividing module can be connected to the connection point of the first diode D1 and the second resistor R6. One end of the second resistor R6 is connected to the first diode D1, and the other end of the second resistor R6 is connected in series with the third resistor R7. The other end of the third resistor R7 is connected to the ground as a zero potential point.

[0064] It can be understood that the first voltage signal can be the first divided voltage obtained by the first resistor R5, and the second voltage signal can be the potential of the connection point of the second resistor R6 and the third resistor R7 to the ground. Since the signal input end of the gear control module is connected to the connection point of the second resistor R6 and the third resistor R7, the gear control module detects the potential of the connection point of the second resistor R6 and the third resistor R7 to the ground. When the power supply is disconnected, the gear control module detects that the potential of the connection point of the second resistor R6 and the third resistor R7 to the ground becomes zero, and then outputs a control signal different from the current control signal.

[0065] In an embodiment, the first resistor R5 can have a resistance of 4.7 kΩ, the second resistor R6 can have a resistance of 10 kΩ, and the third resistor R7 can have a resistance of 1.2 kΩ. The first diode D1 can be a B5819W diode.

[0066] In the exhaust fan driving circuit provided by some embodiments of the present application, as shown in Figure 2 The gear control module includes a control chip U3. When the power is disconnected, the potential of the connection point decreases. After the control chip U3 detects the decrease of the potential of the connection point, the control chip U3 outputs a control signal different from the current control signal.

[0067] Specifically, the gear control module includes a control chip U3. The energy storage power supply module is configured to supply power to the control chip U3. The first voltage signal output by the power supply voltage dividing module is configured to supply power to the control chip U3. The control chip U3 is configured to detect the second voltage signal. The control signal output by the control chip U3 is configured to control the motor of the exhaust fan. Specifically, the second port and the fifth port of the control chip U3 are configured to be the positive and negative poles of the chip power input end. The energy storage power supply module is connected to the second port and the fifth port of the control chip U3. The output end of the power supply voltage dividing module, i.e., the end of the first resistor R5 away from the first diode D1, is also connected to the second port and the fifth port of the control chip U3. The first port of the control chip U3 is configured to be a signal input end. The first port of the control chip U3 is connected to the connection point of the second resistor R6 and the third resistor R7. The sixth port of the control chip U3 is configured to be a signal output end. The sixth port of the control chip U3 is connected to the driving module to output the control signal to the driving module. In addition, the second port of the control chip U3 is grounded.

[0068] The control chip U3 is configured to, when the power is disconnected, the second voltage signal disappears, and the potential of the connection point of the second resistor R6 and the third resistor R7 decreases to zero. After the control chip U3 detects the disappearance of the second voltage signal, i.e., the decrease of the potential of the connection point of the second resistor R6 and the third resistor R7 to zero, the control chip U3 outputs a control signal different from the current control signal.

[0069] In an embodiment, the control chip U3 can be a chip in an SOT23-6 package.

[0070] In another embodiment, the control chip U3 can be a dimming chip in an SOT23-6 package.

[0071] In the exhaust fan driving circuit provided by some embodiments of the present application, as shown in Figure 2 The power supply voltage dividing module further includes a voltage stabilizing diode D3 configured to stabilize the first voltage dividing signal.

[0072] Specifically, the power supply voltage dividing module further comprises a voltage stabilizing diode D3, a negative electrode of the voltage stabilizing diode D3 is connected to a connection point of the first resistor R5 and a negative electrode of the power input terminal of the gear control module, and a positive electrode of the voltage stabilizing diode D3 is connected to a positive electrode of the power input terminal of the gear control module, so that the voltage stabilizing diode D3 can stabilize the first voltage dividing signal.

[0073] In an embodiment, the voltage stabilizing diode D3 can be a voltage stabilizing diode with a stable voltage of 5.1V.

[0074] In the exhaust fan driving circuit provided in some embodiments of the present application, the control signal output by the gear control module comprises a first control signal and a second control signal, the operating gears comprise a first operating gear corresponding to the first control signal and a second operating gear corresponding to the second control signal, when the power supply is disconnected, the control signal output by the gear control module is converted from the first control signal to the second control signal, and the operating gear of the exhaust fan is converted from the first operating gear to the second operating gear.

[0075] Specifically, the control signal output by the gear control module comprises a first control signal and a second control signal, the operating gears comprise a first operating gear corresponding to the first control signal and a second operating gear corresponding to the second control signal, when the power supply is powered, i.e. when the exhaust fan is powered on, the first voltage signal powers the gear control module, the second voltage signal does not change, the control signal output by the gear control module is the first control signal, at this time, the driving module drives the motor of the exhaust fan at the first operating gear corresponding to the first control signal according to the first control signal; when the power supply is disconnected, the energy storage power supply module powers the gear control module, the first voltage signal and the second voltage signal disappear, i.e. the second voltage signal changes, after the gear control module detects the change of the second voltage signal, it outputs a control signal different from the current one in response to the change of the second voltage signal, i.e. outputs the second control signal different from the current first control signal, so that the driving module drives the motor of the exhaust fan at the second operating gear corresponding to the second control signal according to the second control signal, and the operating gear of the exhaust fan is converted from the first operating gear to the second operating gear.

[0076] It can be understood that the first control signal and the second control signal are different, and the first control signal and the second control signal can be different in signal waveform, signal frequency or logic level, etc.; the first operating gear and the second operating gear are also different, and in the first operating gear and the second operating gear, the first operating gear can be high gear and the second operating gear can be low gear, or the first operating gear can be low gear and the second operating gear can be high gear, and when the exhaust fan operates at different gears, the motor of the exhaust fan can operate at different speeds.

[0077] In the exhaust fan driving circuit provided in some embodiments of the present application, the first control signal and the second control signal are pulse signals with different duty cycles.

[0078] Specifically, the first control signal and the second control signal are pulse signals with different duty cycles, i.e., pulse width modulation signals (PWM signals). The driving module is used to receive the detection pulse signal and drive the exhaust fan motor at different operating gears according to the duty cycle of the pulse signal.

[0079] In the exhaust fan driving circuit provided in some embodiments of the present application, Figure 2 As shown, the driving module includes a driving chip U2 and a fourth resistor R8. The output end of the driving chip U2 is connected to the exhaust fan motor. One end of the fourth resistor R8 is connected to the driving chip U2, and the other end of the fourth resistor R8 is connected to the gear control module.

[0080] Specifically, the driving module includes a driving chip U2 and a fourth resistor R8. The sixth port of the driving chip U2 is a signal input port, that is, a PWM input port. The third port and the fourth port of the driving chip U2 are control output ports, which are respectively connected to the control lines of the exhaust fan motor to realize control of the exhaust fan motor. The second port and the fifth port of the driving chip U2 are the power input ports of the driving chip U2. One end of the fourth resistor R8 is connected to the sixth port of the driving chip U2, and the other end of the fourth resistor R8 is connected to the gear control module.

[0081] In one embodiment, the driver chip U2 may be a MLX90411-24V driver chip, and the resistance of the fourth resistor R8 may be 1 k ohm.

[0082] A second aspect of the present application provides an exhaust fan, which includes any of the above-mentioned exhaust fan driving circuits.

[0083] The embodiments of the present application are described in detail above in conjunction with the accompanying drawings, but the present application is not limited to the above embodiments. Various changes can be made within the scope of knowledge possessed by ordinary technicians in the technical field without departing from the purpose of the present application.

Claims

1. An exhaust fan drive circuit, characterized by, The application relates to a power supply device for an exhaust fan, which comprises the following parts: a rectifier module for converting alternating voltage output by a power supply into direct current voltage; a gear control module for outputting control signals to control the motor of the exhaust fan to run and outputting different control signals to switch the running gear of the motor of the exhaust fan; a driving module for driving the motor of the exhaust fan in different running gears according to the control signals output by the gear control module, wherein the driving module is connected to the gear control module; an energy storage power supply module connected to the gear control module, which is used for supplying power to the gear control module when the power supply is disconnected to maintain the running of the gear control module; a power supply voltage dividing module for dividing the direct current voltage output by the rectifier module into first voltage signals and second voltage signals, wherein the first voltage signals are used for supplying power to the gear control module when the power supply is connected, and the second voltage signals change when the power supply is disconnected, and the gear control module outputs different control signals in response to the change of the second voltage signals to switch the running gear of the motor of the exhaust fan, and the input end of the power supply voltage dividing module is connected to the output end of the rectifier module.

2. The exhaust fan drive circuit according to claim 1, characterized by The energy storage power supply module comprises an energy storage capacitor, wherein the first voltage signals are used for charging the energy storage capacitor when the power supply is connected and the first voltage signals are used for supplying power to the gear control module. The energy storage capacitor supplies power to the gear control module when the power supply is disconnected.

3. The exhaust fan drive circuit according to claim 1, characterized by When the power supply is disconnected, the first voltage signals are used for supplying power to the gear control module during the period when the energy storage power supply module supplies power to the gear control module, if the power supply is connected again, the first voltage signals are used for supplying power to the gear control module, and the driving module runs in the current running gear, if the power supply is not connected, the gear control module loses power, and the exhaust fan stops running.

4. The exhaust fan drive circuit according to claim 1, characterized by The power supply voltage dividing module comprises a first diode, a first resistor, a second resistor and a third resistor, the power supply voltage dividing module divides the direct current voltage output by the rectifier module through the first resistor to output the first voltage signals, divides the direct current voltage output by the rectifier module through the second resistor and the third resistor to output the second voltage signals, one end of the first resistor is connected to one end of the first diode, the second resistor and the third resistor are connected to the other end of the first diode, the gear control module is connected to the connection point of the second resistor and the third resistor, and the second voltage signals are the potential of the connection point.

5. The exhaust fan drive circuit according to claim 4, characterized in that, The gear control module comprises a control chip, which is configured to: when the power supply is disconnected, the potential of the connection point decreases, and the control chip detects the decrease of the potential of the connection point and outputs different control signals.

6. The exhaust fan drive circuit according to claim 4, characterized by The power supply voltage dividing module further comprises a voltage stabilizing diode for stabilizing the first voltage signals.

7. The exhaust fan drive circuit according to claim 1, characterized by The control signals output by the gear control module comprise first control signals and second control signals, the running gears comprise first running gears corresponding to the first control signals and second running gears corresponding to the second control signals, when the power supply is disconnected, the control signals output by the gear control module are converted from the first control signals to the second control signals, and the running gears of the exhaust fan are converted from the first running gears to the second running gears.

8. The exhaust fan drive circuit according to claim 7, characterized in that, The first control signals and the second control signals are pulse signals with different duty ratios.

9. The exhaust fan drive circuit according to claim 1, characterized by The driving module comprises a driving chip and a fourth resistor, the output end of the driving chip is connected to the motor of the exhaust fan, one end of the fourth resistor is connected to the driving chip, and the other end of the fourth resistor is connected to the gear control module.

10. An exhaust fan characterized by, The exhaust fan driving circuit according to any one of claims 1 to 9, further comprising a power switch.

Images