Gear adjusting method of range hood

Abstract

The invention discloses a gear adjusting method of a range hood, which comprises the following steps: controlling a power switch of the range hood to be turned on, monitoring external voltage of a power line of the range hood to obtain an actual external voltage value, and transmitting the actual external voltage value to a range hood controller; the controller selects control logic from preset gears according to the actual external voltage value, then the corresponding control switch is selected to be turned on, the draught fan operates according to the gears turned on by the controller, and when the external voltage changes, the draught fan is switched on by the controller. And the controller adjusts in real time according to the voltage change so as to intelligently switch the gears among the plurality of gears, so that the adjustment of the working voltage of the driving motor can be realized by adjusting the resistance value of the adjustable resistor connected in series with the fan, and the stable performance of the range hood is ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of household appliances, and in particular to a gear adjustment method for a range hood. Background Art

[0002] In the existing technology, most range hoods equipped with AC asynchronous motors do not have voltage detection and adjustment functions. The actual civilian voltage range is 198-242V, with a span of 44V. Voltage fluctuations have a great impact on the performance of AC motors. The higher the voltage, the greater the motor noise. When the voltage is low, the smoke extraction ability of the range hood will also decrease. The unstable performance caused by voltage will seriously affect the quality of the range hood. Summary of the invention

[0003] The present invention aims to solve at least one of the problems existing in the existing related technologies to a certain extent. To this end, the present invention proposes a gear adjustment method for a range hood. The method is simple and feasible. The external voltage of the range hood is detected and the appropriate gear is automatically matched according to the detected size of the external voltage of the range hood to control the range hood to work according to the matched gear information, thereby ensuring the stable performance of the range hood.

[0004] The above purpose is achieved through the following technical solutions:

[0005] A range hood gear adjustment method, the range hood comprising a fan drive motor and an adjustable resistor connected in series with an external power supply, the gear adjustment method comprising the following steps:

[0006] The adjustable resistor is pre-set with a plurality of different resistance access positions, and the resistance value of each position connected to the series circuit is different and is divided according to the voltage value of the external power supply; wherein the voltage boost adjustment ratio of the drive motor corresponding to the plurality of positions is negatively correlated with the voltage value of the external power supply;

[0007] Turning on the range hood;

[0008] Detecting the voltage of the external power supply of the range hood to obtain the current actual external voltage value;

[0009] Matching the current actual external voltage value with the external voltage values ​​corresponding to the plurality of gears, and acquiring the gear corresponding to the current actual external voltage value;

[0010] The adjustable resistor is connected to the series circuit according to the gear position, and the working voltage of the drive motor is adjusted to make the range hood work stably.

[0011] In some embodiments, the adjustable resistor is pre-set with a plurality of different resistance access positions, and the resistance value of each position connected to the series circuit is different and is divided according to the voltage value of the external power supply; wherein the step of the voltage boost adjustment ratio of the drive motor corresponding to the plurality of positions being negatively correlated with the voltage value of the external power supply comprises:

[0012] A reference gear is preset, and the reference gear is that when the actual external voltage value is 220V, the working voltage value of the fan is less than or equal to 198V, and the reference resistance value of the adjustable resistor is 15% of the actual resistance value of the fan;

[0013] A plurality of gears are pre-set in sequence from small to large according to the voltage value of the external power supply, and the voltage boost adjustment ratios of the drive motor corresponding to the plurality of gears decrease in sequence.

[0014] In some embodiments, the step of pre-setting a plurality of gears in ascending order according to the voltage value of the external power supply, and the step of decreasing the voltage boost adjustment ratios of the drive motor corresponding to the plurality of gears in descending order comprises:

[0015] In the first gear, the voltage value of the external power supply is greater than or equal to 100V and less than 200V, and the corresponding boost adjustment ratio of the drive motor is 12.5%;

[0016] In the second gear, the voltage of the external power supply is greater than or equal to 200V and less than 205V, and the corresponding boost adjustment ratio of the drive motor is 9.5%;

[0017] The third gear, the voltage value of the external power supply is greater than or equal to 205V and less than 210V, and the corresponding boost adjustment ratio of the drive motor is 7%;

[0018] The fourth gear, the voltage value of the external power supply is greater than or equal to 210V and less than 215V, and the corresponding boost adjustment ratio of the drive motor is 4.5%;

[0019] The fifth gear position has an external power supply voltage greater than or equal to 215V and less than 220V, and the corresponding drive motor voltage boost adjustment ratio is 2%;

[0020] The sixth gear position, the voltage value of the external power supply is greater than or equal to 220V and less than 225V, and the corresponding boost adjustment ratio of the drive motor is 0%;

[0021] In the seventh gear, the voltage of the external power supply is greater than or equal to 225V and less than 230V, and the corresponding boost adjustment ratio of the drive motor is -2.2%;

[0022] In the eighth gear, the voltage of the external power supply is greater than or equal to 230V and less than 235V, and the corresponding boost adjustment ratio of the drive motor is -4.4%;

[0023] The ninth gear position, the voltage value of the external power supply is greater than or equal to 235V and less than 240V, and the corresponding boost adjustment ratio of the drive motor is -6.6%;

[0024] In the tenth gear, the voltage value of the external power supply is greater than or equal to 240V and less than 300V, and the corresponding boost adjustment ratio of the drive motor is -8.5%.

[0025] In some embodiments, the step of connecting the adjustable resistor to the series circuit according to the gear position and adjusting the working voltage of the drive motor to enable the range hood to work stably includes:

[0026] The voltage adjustment ratio corresponding to the matched gear position is calculated by a calculation formula to obtain the adjustment resistance value;

[0027] The fan is controlled to work according to the calculated adjustment resistance value, and the working voltage of the driving motor is adjusted to enable the range hood to work stably.

[0028] In some embodiments, the adjustable resistance value is calculated by the following calculation formula: Ri=(R0+Rreference) / (1+ai)-R0, wherein Ri is the adjustable resistance value, R0 is the operating voltage value of the drive motor, Rreference is the reference resistance value of the adjustable resistor, and ai is the boost adjustment ratio of the drive motor corresponding to each gear.

[0029] In some embodiments, the step of connecting the adjustable resistor to the series circuit according to the gear position and adjusting the working voltage of the drive motor to make the range hood work stably includes:

[0030] Continuing to monitor the voltage of the external power supply of the range hood;

[0031] When the voltage of the external power supply of the range hood changes, the corresponding gear is matched to the gear among the multiple gears according to the voltage of the external power supply of the range hood;

[0032] The adjustable resistor is connected to the series circuit according to the gear position to adjust the working voltage of the drive motor, and this cycle is repeated to ensure that the range hood works stably.

[0033] In some embodiments, if the current actual external voltage value fails to match the external voltage values ​​corresponding to the plurality of gears, the range hood is turned off.

[0034] In some embodiments, a voltage sensor is provided at the input end of the power line of the range hood, and the external voltage condition of the range hood is acquired by detecting the voltage signal at the input end of the power line of the range hood.

[0035] In some implementations, a plurality of interfaces are respectively provided on the adjustable resistor, the plurality of interfaces are arranged corresponding to the plurality of gears, and each of the interfaces is electrically connected to the controller via a lead.

[0036] In some embodiments, a plurality of control switches are further included, and the plurality of control switches are respectively connected to the plurality of interfaces to control the switch of a single gear position.

[0037] In some embodiments, the length position of each of the interfaces is different.

[0038] Compared with the prior art, the present invention has at least the following beneficial effects:

[0039] 1. The gear adjustment method of the range hood of the present invention is simple and feasible. By detecting the external voltage of the range hood and automatically matching the appropriate gear according to the detected size of the external voltage of the range hood, the range hood is controlled to work according to the matched gear information, thereby ensuring the stable performance of the range hood. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0041] Figure 1 Schematic diagram of the process of the gear adjustment method in the embodiment of the present invention. DETAILED DESCRIPTION

[0042] To make the purpose, technical solution and advantages of the present invention clearer, the technical solution in the embodiment of the present invention will be clearly and completely described below in combination with the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, but not all of the embodiments. The components of the embodiment of the present invention can be arranged and designed in various different configurations.

[0043] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of the technical solution claimed for protection of the present invention.

[0044] Example:

[0045] like Figure 1 As shown, this embodiment provides a range hood gear adjustment method, the range hood includes a fan drive motor and an adjustable resistor connected in series, and at the same time, a plurality of interfaces are respectively provided on the adjustable resistor, the plurality of interfaces are arranged corresponding to the plurality of gears, each interface is electrically connected to the controller through a lead, and a plurality of control switches are respectively connected to the plurality of interfaces corresponding to control the switch of a single gear, and the length and position of each interface are different. Specifically, the adjustable resistor is made into a long strip, and 10 interfaces with different lengths and positions are led out, so as to adjust 10 different resistors, and each resistor interface is individually wired, and each interface is finally connected to the control switch of the circuit board through the lead.

[0046] In addition, a voltage sensor is provided at the input end of the power cord of the range hood. The voltage signal at the input end of the power cord of the range hood is detected to obtain the external voltage condition of the range hood. The voltage sensor transmits the external voltage value detected in real time to the controller of the range hood. The controller of the range hood matches the received external voltage value against the external voltage value corresponding to each gear, thereby matching it to the corresponding gear, and then selects to turn on the matched gear to control the fan to work. If the current actual external voltage value fails to match the set external voltage values ​​corresponding to multiple gears, the range hood is turned off.

[0047] In this embodiment, the power switch of the range hood is turned on, the external voltage of the range hood power line is monitored to obtain the actual external voltage value, and the actual external voltage value is transmitted to the range hood controller. The controller selects the control logic in the pre-set gear according to the actual external voltage value, and then selects to turn on the corresponding control switch. The fan operates at the gear turned on by the controller. When the external voltage changes, the controller adjusts in real time according to the voltage change to intelligently switch the gear among multiple gears. In this way, the resistance value of the adjustable resistor connected in series with the fan can be adjusted to achieve the adjustment of the driving motor working voltage, thereby ensuring the stable performance of the range hood. The method is simple and feasible. By detecting the external voltage of the range hood and automatically matching the appropriate gear according to the detected size of the external voltage of the range hood to control the range hood to work according to the matched gear information, the stable performance of the range hood is ensured.

[0048] The gear adjustment method in this embodiment includes the following steps:

[0049] In step S101, the adjustable resistor is pre-set with multiple different resistance access positions, and the resistance value of each position connected to the series circuit is different and is divided according to the voltage value of the external power supply; wherein the boost adjustment ratio of the drive motor corresponding to the multiple positions is negatively correlated with the voltage value of the external power supply.

[0050] In this embodiment, the adjustable resistor is pre-set with a plurality of different resistance access positions, and the resistance value of each position connected to the series circuit is different and is divided according to the voltage value of the external power supply; wherein the step of the voltage boost adjustment ratio of the drive motor corresponding to the plurality of positions being negatively correlated with the voltage value of the external power supply includes:

[0051] A reference gear is preset. When the actual external voltage is 220V, the working voltage of the fan is less than or equal to 198V, and the reference resistance value of the adjustable resistor is 15% of the actual resistance value of the fan.

[0052] A plurality of gears are pre-set in sequence from small to large according to the voltage value of the external power supply, and the voltage boost adjustment ratios of the drive motor corresponding to the plurality of gears decrease in sequence.

[0053] In this embodiment, a plurality of gears are pre-set in order from small to large according to the voltage value of the external power supply, and the step of decreasing the voltage boost adjustment ratio of the drive motor corresponding to the plurality of gears in order includes:

[0054] In the first gear, the voltage value of the external power supply is greater than or equal to 100V and less than 200V, and the corresponding boost adjustment ratio of the drive motor is 12.5%;

[0055] In the second gear, the voltage of the external power supply is greater than or equal to 200V and less than 205V, and the corresponding boost adjustment ratio of the drive motor is 9.5%;

[0056] The third gear, the voltage value of the external power supply is greater than or equal to 205V and less than 210V, and the corresponding boost adjustment ratio of the drive motor is 7%;

[0057] The fourth gear, the voltage value of the external power supply is greater than or equal to 210V and less than 215V, and the corresponding boost adjustment ratio of the drive motor is 4.5%;

[0058] The fifth gear position has an external power supply voltage greater than or equal to 215V and less than 220V, and the corresponding drive motor voltage boost adjustment ratio is 2%;

[0059] The sixth gear position, the voltage value of the external power supply is greater than or equal to 220V and less than 225V, and the corresponding boost adjustment ratio of the drive motor is 0%;

[0060] In the seventh gear, the voltage of the external power supply is greater than or equal to 225V and less than 230V, and the corresponding boost adjustment ratio of the drive motor is -2.2%;

[0061] In the eighth gear, the voltage of the external power supply is greater than or equal to 230V and less than 235V, and the corresponding boost adjustment ratio of the drive motor is -4.4%;

[0062] The ninth gear position, the voltage value of the external power supply is greater than or equal to 235V and less than 240V, and the corresponding boost adjustment ratio of the drive motor is -6.6%;

[0063] In the tenth gear, the voltage value of the external power supply is greater than or equal to 240V and less than 300V, and the corresponding boost adjustment ratio of the drive motor is -8.5%.

[0064] Step S102, turning on the range hood.

[0065] Step S103, detecting the voltage of the external power supply of the range hood to obtain the current actual external voltage value.

[0066] Step S104, matching the current actual external voltage value with the external voltage values ​​corresponding to the multiple gears, and acquiring the gear corresponding to the current actual external voltage value.

[0067] Step S105, connecting an adjustable resistor to the series circuit according to the gear position, and adjusting the working voltage of the driving motor to make the range hood work stably.

[0068] Specifically, the steps of connecting the adjustable resistor to the series circuit according to the gear position and adjusting the working voltage of the driving motor to make the range hood work stably include:

[0069] The corresponding voltage adjustment ratio of the matched gear is calculated through the calculation formula to obtain the adjustment resistance value;

[0070] The fan is controlled to work according to the calculated adjustment resistance value, and the working voltage of the driving motor is adjusted to make the range hood work stably.

[0071] In this embodiment, the adjustment resistance value is calculated by the following calculation formula: Ri=(R0+Rreference) / (1+ai)-R0, where Ri is the adjustment resistance value, R0 is the operating voltage value of the drive motor, Rreference is the reference resistance value of the adjustable resistor, and ai is the boost adjustment ratio of the drive motor corresponding to each gear.

[0072] In this embodiment, the steps of controlling the fan to work according to the calculated adjustment resistance value and adjusting the working voltage of the driving motor to make the range hood work stably include:

[0073] Continue to monitor the voltage of the external power supply of the range hood;

[0074] When the voltage of the external power supply of the range hood changes, the corresponding gear is matched among the multiple gears according to the voltage of the external power supply of the range hood;

[0075] According to the gear position, an adjustable resistor is connected to the series circuit to adjust the working voltage of the drive motor, and this cycle is repeated to ensure stable operation of the range hood.

[0076] More preferably, the operating voltage of the drive motor is adjusted by adjusting the resistance of the adjustable resistor connected in series with the fan drive motor. Since the adjustable resistor in series is in the shape of a long strip, the resistance of the adjustable resistor can be adjusted by connecting different lengths of the lead wire. The maximum adjustable resistor should meet the requirement of connecting the complete resistor in series. When the actual external voltage value is 220V, the operating voltage value of the drive motor is less than or equal to 198V. The reference resistance value Rreference of the adjustable resistor connected in the reference gear is calculated according to the resistance ratio. The reference resistance value of the adjustable resistor is greater than or equal to 11.11% of the actual resistance value of the fan. In order to meet the design requirements of the boost and buck gears at the same time, the reference resistance value of the adjustable resistor can be greater than or equal to 15% of the actual resistance value of the drive motor. Since the adjustment formula of the motor voltage is The working voltage value of the driving motor is R0, the external resistance value of the adjustable resistor is R, the external voltage value of the range hood is U, and the working voltage value of the driving motor is U0. According to the above calculation formula, the working voltage of the driving motor can be adjusted by adjusting the size of the adjustable resistor, and the adjustment of the working voltage of the driving motor changes at a ratio of 1 / (1+R / R0). The voltage adjustment ratio of the i-th gear among multiple gears is ai, and the adjustment resistance value is calculated by the following calculation formula: Ri=(R0+Rbase) / (1+ai)-R0, wherein Ri is the adjustment resistance value, R0 is the working voltage value of the driving motor, Rbase is the reference resistance value of the adjustable resistor, and ai is the boost adjustment ratio of the driving motor corresponding to each gear.

[0077] The gear information of multiple gears specifically includes:

[0078] In the first gear, the external voltage value is greater than or equal to 100V and less than 200V, and the voltage regulation ratio is 12.5%. Then, the above-mentioned calculation formula for adjusting the resistance value can be used to calculate R1=(R0+Rbase) / (1+12.5%)-R0, so that the working voltage value of the drive motor increases by 12.5% ​​relative to the base resistance value of the adjustable resistor;

[0079] In the second gear, the external voltage value is greater than or equal to 200V and less than 205V, and the voltage regulation ratio is 9.5%. Then, the above-mentioned calculation formula for adjusting the resistance value can be used to calculate R2=(R0+Rbase) / (1+9.5%)-R0, so that the working voltage value of the drive motor increases by 9.5% relative to the base resistance value of the adjustable resistor;

[0080] In the third gear, the external voltage value is greater than or equal to 205V and less than 210V, and the voltage regulation ratio is 7%. Then, the above-mentioned calculation formula for adjusting the resistance value can be used to calculate R3=(R0+Rbase) / (1+7%)-R0, so that the working voltage value of the drive motor increases by 7% relative to the base resistance value of the adjustable resistor;

[0081] In the fourth gear, the external voltage value is greater than or equal to 210V and less than 215V, and the voltage regulation ratio is 4.5%. Then, the above-mentioned calculation formula for adjusting the resistance value can be used to calculate R4=(R0+Rbase) / (1+4.5%)-R0, so that the working voltage value of the drive motor increases by 4.5% relative to the base resistance value of the adjustable resistor.

[0082] In the fifth gear, the external voltage value is greater than or equal to 215V and less than 220V, and the voltage regulation ratio is 2%. Then, the above-mentioned calculation formula for adjusting the resistance value can be used to calculate R5=(R0+Rbase) / (1+2%)-R0, so that the working voltage value of the drive motor increases by 2% relative to the base resistance value of the adjustable resistor.

[0083] The sixth gear, its external voltage value is greater than or equal to 220V and less than 225V. Since its voltage regulation ratio is 0%, the reference resistance value of the adjustable resistor at this time is based on the voltage ratio allocated to the drive motor at this time;

[0084] In the seventh gear, the external voltage value is greater than or equal to 225V and less than 230V, and the voltage regulation ratio is -2.2%. Then, the above-mentioned calculation formula for adjusting the resistance value can be used to calculate R7=(R0+Rbase) / (1-2.2%)-R0, so that the working voltage value of the drive motor is reduced by 2.2% relative to the base resistance value of the adjustable resistor.

[0085] In the eighth gear, the external voltage value is greater than or equal to 230V and less than 235V, and the voltage regulation ratio is -4.4%. Then, the above-mentioned calculation formula for adjusting the resistance value can be used to calculate R8=(R0+Rbase) / (1-4.4%)-R0, so that the working voltage value of the drive motor is reduced by 4.4% relative to the base resistance value of the adjustable resistor.

[0086] In the ninth gear, the external voltage value is greater than or equal to 235V and less than 240V, and the voltage regulation ratio is -6.6%. Then, the above-mentioned calculation formula for adjusting the resistance value can be used to calculate R9=(R0+Rbase) / (1-6.6%)-R0, so that the working voltage value of the drive motor is reduced by 6.6% relative to the base resistance value of the adjustable resistor.

[0087] For the tenth gear, the external voltage value is greater than or equal to 240V and less than 300V, and the voltage regulation ratio is -8.5%. Then, the above-mentioned calculation formula for adjusting the resistance value can be used to calculate R10=(R0+Rbase) / (1-8.5%)-R0, thereby reducing the working voltage value of the drive motor by 8.5% relative to the base resistance value of the adjustable resistor.

[0088] The above are only some embodiments of the present invention. For those skilled in the art, several modifications and improvements can be made without departing from the creative concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A method for regulating the motor voltage of a range hood, characterized in that: The range hood comprises a fan drive motor and an adjustable resistor connected in series with an external power source, and the gear adjustment method comprises the following steps: The adjustable resistor is pre-set with a plurality of different resistance access positions, and the resistance value of each position connected to the series circuit is different and is divided according to the voltage value of the external power supply; wherein the voltage boost adjustment ratio of the drive motor corresponding to the plurality of positions is negatively correlated with the voltage value of the external power supply; Turning on the range hood; Detecting the voltage of the external power supply of the range hood to obtain the current actual external voltage value; Matching the current actual external voltage value with the external voltage values ​​corresponding to the plurality of gears, and acquiring the gear corresponding to the current actual external voltage value; The adjustable resistor is connected to the series circuit according to the gear position, and the working voltage of the drive motor is adjusted to make the range hood work stably.

2. The range hood gear adjustment method according to claim 1, characterized in that: The adjustable resistor is pre-set with a plurality of different resistance access positions, and the resistance value of each position connected to the series circuit is different and is divided according to the voltage value of the external power supply; wherein the step of the voltage boost adjustment ratio of the drive motor corresponding to the plurality of positions being negatively correlated with the voltage value of the external power supply comprises: A reference gear is preset, and the reference gear is that when the actual external voltage value is 220V, the working voltage value of the drive motor is less than or equal to 198V, and the reference resistance value of the adjustable resistor is 15% of the actual resistance value of the fan; A plurality of gears are pre-set in sequence from small to large according to the voltage value of the external power supply, and the voltage boost adjustment ratios of the drive motor corresponding to the plurality of gears decrease in sequence.

3. The range hood gear adjustment method according to claim 2, characterized in that: The steps of pre-setting a plurality of gears in order from small to large according to the voltage value of the external power supply, and the voltage boost adjustment ratios of the drive motors corresponding to the plurality of gears decreasing in order include: In the first gear, the voltage value of the external power supply is greater than or equal to 100V and less than 200V, and the corresponding boost adjustment ratio of the drive motor is 12.5%; In the second gear, the voltage of the external power supply is greater than or equal to 200V and less than 205V, and the corresponding boost adjustment ratio of the drive motor is 9.5%; The third gear, the voltage value of the external power supply is greater than or equal to 205V and less than 210V, and the corresponding boost adjustment ratio of the drive motor is 7%; The fourth gear, the voltage value of the external power supply is greater than or equal to 210V and less than 215V, and the corresponding boost adjustment ratio of the drive motor is 4.5%; The fifth gear position has an external power supply voltage greater than or equal to 215V and less than 220V, and the corresponding drive motor voltage boost adjustment ratio is 2%; The sixth gear position, the voltage value of the external power supply is greater than or equal to 220V and less than 225V, and the corresponding boost adjustment ratio of the drive motor is 0%; In the seventh gear, the voltage of the external power supply is greater than or equal to 225V and less than 230V, and the corresponding boost adjustment ratio of the drive motor is -2.2%; In the eighth gear, the voltage of the external power supply is greater than or equal to 230V and less than 235V, and the corresponding boost adjustment ratio of the drive motor is -4.4%; The ninth gear position, the voltage value of the external power supply is greater than or equal to 235V and less than 240V, and the corresponding boost adjustment ratio of the drive motor is -6.6%; In the tenth gear, the voltage value of the external power supply is greater than or equal to 240V and less than 300V, and the corresponding boost adjustment ratio of the drive motor is -8.5%.

4. The range hood gear adjustment method according to claim 2, characterized in that: The step of connecting the adjustable resistor to the series circuit according to the gear position and adjusting the working voltage of the drive motor to enable the range hood to work stably includes: The voltage adjustment ratio corresponding to the matched gear position is calculated by a calculation formula to obtain the adjustment resistance value; The fan is controlled to work according to the calculated adjustment resistance value, and the working voltage of the driving motor is adjusted to enable the range hood to work stably.

5. The range hood gear adjustment method according to claim 4, characterized in that: The adjustable resistance value is calculated by the following calculation formula: Ri=(R0+Rbase) / (1+ai)-R0, wherein Ri is the adjustable resistance value, R0 is the working voltage value of the drive motor, Rbase is the reference resistance value of the adjustable resistor, and ai is the boost adjustment ratio of the drive motor corresponding to each gear.

6. The range hood gear adjustment method according to claim 1, characterized in that: The steps of connecting the adjustable resistor to the series circuit according to the gear position and adjusting the working voltage of the drive motor so that the range hood can work stably include: Continuing to monitor the voltage of the external power supply of the range hood; When the voltage of the external power supply of the range hood changes, the corresponding gear is matched to the gear among the multiple gears according to the voltage of the external power supply of the range hood; The adjustable resistor is connected to the series circuit according to the gear position to adjust the working voltage of the drive motor, and this cycle is repeated to ensure that the range hood works stably.

7. The range hood gear adjustment method according to claim 1, characterized in that: If the current actual external voltage value fails to match the external voltage values ​​corresponding to the multiple gears, the range hood is turned off.

8. The range hood gear adjustment method according to claim 1, characterized in that: A voltage sensor is provided at the input end of the power line of the range hood, and the external voltage condition of the range hood is obtained by detecting the voltage signal at the input end of the power line of the range hood.

9. The range hood gear adjustment method according to claim 1, characterized in that: A plurality of interfaces are respectively arranged on the adjustable resistor, the plurality of interfaces are arranged corresponding to the plurality of gears, and each of the interfaces is electrically connected to the controller via a lead.

10. The range hood gear adjustment method according to claim 9, characterized in that: It also includes a plurality of control switches, which are respectively connected to the plurality of interfaces to control the switch of a single gear position.

11. The range hood gear adjustment method according to claim 9, characterized in that: The length and position of each interface are different.

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