Method of reducing noise, control device, blow dryer

Abstract

Embodiments of this disclosure relate to a method, control device, and hair dryer for noise reduction. The hair dryer includes a motor and a power supply unit with a rectifier circuit; the motor includes a stator and a rotor. The method includes: detecting the output voltage of the rectifier circuit; determining whether the output voltage is less than a threshold; and, in response to the output voltage being less than the threshold, controlling the back electromotive force of the motor to be less than or equal to the output voltage. The proposed method prevents the hair dryer motor from entering an active deceleration process, thereby reducing noise generation.

Description

Technical Field

[0001] The embodiments of the present invention generally relate to a method, control device, and hair dryer for reducing noise, and more specifically, to a method, control device, and hair dryer for reducing noise of a high-speed, small-volume hair dryer. Background Technology

[0002] High-speed hair dryers are characterized by their small size and large air volume, and have become increasingly popular with consumers in recent years. However, due to their small size and extremely high motor speed (generally exceeding 100,000 revolutions per minute), noise has always been a difficult problem to solve. Summary of the Invention

[0003] The embodiments of this disclosure provide a method, control device, and hair dryer for reducing noise, which can minimize the active deceleration process of the hair dryer's motor, thereby at least partially solving the above-mentioned and other potential problems existing in the prior art.

[0004] The first aspect of this disclosure relates to a method for reducing noise in a hair dryer, the hair dryer including a motor and a power supply unit having a rectifier circuit, the motor including a stator and a rotor. The method includes: detecting the output voltage of the rectifier circuit; determining whether the output voltage is less than a threshold; and, in response to the output voltage being less than the threshold, controlling the back electromotive force of the motor to be less than or equal to the output voltage.

[0005] The above embodiments prevent the hair dryer motor from entering an active deceleration process, thereby reducing noise generation.

[0006] According to one embodiment, the threshold is the back electromotive force of the motor or a preset constant value. Through the above embodiment, noise generation can be reduced while ensuring the motor speed.

[0007] According to one embodiment, the method further includes: calculating the stator inductance component of the motor in the d-axis and the stator current component of the motor in the d-axis; obtaining the motor speed; and determining the back electromotive force based at least on the stator inductance component in the d-axis, the stator current component in the d-axis, and the motor speed. Through the above embodiment, a threshold is obtained through internal calculations by the controller, achieving real-time control.

[0008] According to one embodiment, determining the back electromotive force includes: determining the back electromotive force based on the stator inductance component on the d-axis, the stator current component on the d-axis, the motor speed, and a predetermined back electromotive force coefficient.

[0009] According to one embodiment, controlling the back electromotive force of the motor to be less than or equal to the output voltage includes reducing the stator current component of the motor along the d-axis. Through the above embodiment, the back electromotive force of the motor can be controlled while ensuring the motor speed.

[0010] According to one embodiment, reducing the stator current component of the motor in the d-axis includes: reducing the stator current component in the d-axis by setting the stator voltage component of the motor in the d-axis. Through the above embodiment, the stator current component in the d-axis is controlled by internal calculations of the controller, thereby improving control accuracy.

[0011] A second aspect of this disclosure relates to a computer-readable storage medium. This computer-readable storage medium stores a computer program that, when executed by a machine, implements the method as described in any of the foregoing embodiments.

[0012] A third aspect of this disclosure relates to a control device for a hair dryer, the hair dryer including a motor and a power supply unit having a rectifier circuit, the motor including a stator and a rotor. The controller includes: a voltage detection unit configured to detect the output voltage of the rectifier circuit; a control unit; and a memory coupled to the control unit and storing instructions for execution by the control unit, which, when executed by the control unit, cause the control device of the hair dryer to perform the steps of the method according to any of the foregoing embodiments.

[0013] According to one embodiment, the voltage detection unit includes a voltage divider resistor.

[0014] A fourth aspect of this disclosure relates to a hair dryer, comprising: a motor including a stator and a rotor; a power supply unit having a rectifier circuit; and a control device according to any of the foregoing embodiments. Attached Figure Description

[0015] The above and other objects, features, and advantages of embodiments of the present disclosure will become more readily understood from the following detailed description with reference to the accompanying drawings. Several embodiments of the present disclosure will be described by way of example and non-limitation in the drawings.

[0016] Figure 1 The circuit diagram of the power supply unit of the hair dryer is shown.

[0017] Figure 2 The waveforms of the power supply unit output voltage and the back electromotive force of the motor in a hair dryer in the prior art are shown.

[0018] Figure 3 A flowchart of a method for reducing hair dryer noise according to an embodiment of the present disclosure is shown.

[0019] Figure 4 A waveform diagram of the back electromotive force of an electric motor according to an embodiment of the present disclosure is shown.

[0020] Figure 5 A schematic diagram of a controller according to an embodiment of the present disclosure is shown.

[0021] Figure 6A block diagram schematically illustrates a control unit suitable for implementing embodiments of the present invention. Detailed Implementation

[0022] The principles of this disclosure will now be described with reference to various exemplary embodiments shown in the accompanying drawings. It should be understood that the description of these embodiments is merely intended to enable those skilled in the art to better understand and further implement this disclosure, and is not intended to limit the scope of this disclosure in any way. It should be noted that similar or identical reference numerals may be used in the figures where feasible, and similar or identical reference numerals may denote similar or identical functions. Those skilled in the art will readily recognize that alternative embodiments of the structures and methods described herein may be employed without departing from the principles of the invention as described herein.

[0023] The following will combine Figure 1 and Figure 2 This section details the problems existing in current hair dryer technologies. First, refer to... Figure 1 , Figure 1 The circuit diagram of the power supply unit of the hair dryer is shown.

[0024] like Figure 1 As shown, the power supply unit of the hair dryer includes a rectifier unit and a capacitor unit to power the hair dryer's motor. The rectifier unit converts the AC input voltage into DC voltage, while the capacitor unit maintains the DC voltage above a specific value. The larger the capacitance of the capacitor unit, the more stable the DC voltage, and the smaller the fluctuation in motor speed.

[0025] However, because hair dryers are handheld, their size is very limited. Therefore, currently only small-capacity capacitors can be used in hair dryers, resulting in large voltage fluctuations across the capacitors.

[0026] Figure 2 The waveforms of the output voltage of the power supply unit and the back electromotive force of the motor in a prior art hair dryer are shown. For example... Figure 2 As shown, the voltage Vout on the capacitor fluctuates greatly, causing the motor to passively accelerate / decelerate periodically, generating unpleasant noise.

[0027] Meanwhile, when the motor speed is very high, the back electromotive force E, which is proportional to the speed, will be very high, even exceeding the voltage Vout on the capacitor, as shown in time periods t1, t2, and t3. When this occurs, the motor actively charges the capacitor, further intensifying the motor's deceleration process and resulting in increased motor noise. This part of the deceleration is referred to in this disclosure as active motor deceleration.

[0028] To address the aforementioned issues, this disclosure controls the back electromotive force of the hair dryer's motor to be no greater than the output voltage of the power supply unit, thereby preventing the motor from charging the capacitor of the power supply unit and thus preventing the motor from entering an active deceleration process, thereby reducing noise generation.

[0029] The following will combine Figure 3 and Figure 4 This disclosure details the method for reducing hair dryer noise. First, refer to... Figure 3 , Figure 3 A flow chart illustrating a method for reducing hairdryer noise according to embodiments of the present disclosure is shown. It should be understood that method 100 can, for example, be implemented in... Figure 6 The described control unit 600 performs the action. It should be understood that method 100 may also include additional actions not shown and / or the actions shown may be omitted; the scope of the invention is not limited in this respect. Figure 3 As shown, in step 105, the output voltage of the rectifier circuit of the power supply unit of the hair dryer is detected. In some embodiments, the output voltage of the rectifier circuit is detected by setting up a resistor voltage divider network. In other embodiments, other voltage detection methods can also be used to detect the output voltage of the rectifier circuit, which can be determined according to specific design requirements and cost.

[0030] In step 110, it is determined whether the output voltage is less than a threshold.

[0031] At step 115, in response to the output voltage being less than a threshold, the back electromotive force of the motor is controlled to be less than or equal to the output voltage.

[0032] In some embodiments, the method further includes: returning to step 110 in response to the output voltage being not less than a threshold.

[0033] Through the above control method, the back electromotive force of the motor is always less than or equal to the output voltage of the power supply unit. The motor will not actively provide energy to the capacitor of the power supply unit, thus it will not actively decelerate and reduce the generation of noise.

[0034] Figure 4 A waveform diagram of the back electromotive force of a motor according to an embodiment of the present disclosure is shown. For example... Figure 4 As shown, the back electromotive force of the motor decreases accordingly during the time periods t1, t2, and t3 when the output voltage is less than the threshold, and is less than or equal to the output voltage of the power supply unit.

[0035] In some embodiments, the threshold is the back electromotive force (EMF) of the motor. The method for reducing hairdryer noise further includes: calculating the d-axis components of the motor's stator inductance and stator current, obtaining the motor's rotational speed, and determining the back EMF based at least on the d-axis components of the stator inductance and stator current, and the motor's rotational speed. Specifically, the back EMF is calculated based on the following formula:

[0036] E=(Psir+Ld Id) ω,

[0037] Where E is the back electromotive force, Psir is the back electromotive force coefficient, Ld is the stator inductance component on the d-axis, Id is the stator current component on the d-axis, and ω is the rotational speed.

[0038] With the above settings, the back electromotive force of the motor can be calculated in real time, thereby preventing the motor from entering the active deceleration process without reducing the motor speed.

[0039] In some embodiments, the threshold is a preset constant value. For example, the threshold can be set to the maximum value of the motor's back electromotive force. This setting eliminates the need for real-time calculation of the motor's back electromotive force, thus reducing the complexity of control. In other embodiments, the threshold can be set to other values, which can be determined based on specific design requirements and cost.

[0040] In some embodiments, controlling the back electromotive force of the motor to be less than or equal to the output voltage includes reducing the d-axis component of the motor's stator current. Reducing the d-axis component of the motor's stator current includes reducing the d-axis component of the stator current by setting the d-axis component of the motor's stator voltage. Specifically, the d-axis component of the stator current is reduced by setting the d-axis component of the motor's stator voltage based on the following formula:

[0041] Ud=R Id-Lq Iq ω,

[0042] Where Ud is the d-axis component of the stator voltage, R is the resistance of the stator coil, Id is the d-axis component of the stator current, Lq is the q-axis component of the stator inductance, Iq is the q-axis component of the stator current, and ω is the rotational speed.

[0043] By controlling the stator voltage component on the d-axis, the stator current component on the d-axis is indirectly controlled, thereby controlling the motor's back electromotive force E.

[0044] In other embodiments, the back electromotive force of the motor can be controlled in other ways, which can be determined based on specific design requirements and costs.

[0045] Another aspect of this disclosure relates to a computer-readable storage medium. This computer-readable storage medium stores a computer program that, when executed by a machine, implements the methods described in the foregoing embodiments.

[0046] Another aspect of this disclosure relates to a controller for a hair dryer. This will be discussed below in conjunction with... Figure 5 The controller for the hair dryer disclosed herein is described in detail. Figure 5 A schematic diagram of a controller according to an embodiment of the present disclosure is shown.

[0047] like Figure 5 As shown, the controller 200 includes a voltage detection unit 201 and a control unit 202. The voltage detection unit 201 is configured to detect the output voltage of the rectifier circuit. The controller 202 includes a memory 203 coupled to the control unit and storing instructions executed by the control unit to cause the control device of the hair dryer to perform the steps described in the foregoing embodiments.

[0048] In some embodiments, the voltage detection unit 201 includes a voltage divider resistor. In other embodiments, the voltage detection unit 201 may include other voltage detection devices, which may be determined based on specific design requirements and cost.

[0049] Another aspect of this disclosure relates to a hair dryer including a motor, a power supply unit, and a controller. The power supply unit includes a rectifier circuit. The controller includes a control unit as described in the foregoing embodiments.

[0050] Figure 6 A block diagram schematically illustrates a control unit 600 suitable for implementing embodiments of the present invention. The control unit 600 may be used to perform execution... Figure 3 Method 100 is shown. (e.g.) Figure 6 As shown, the control unit 600 includes a central processing unit (i.e., CPU 601), which can perform various appropriate actions and processes according to computer program instructions stored in read-only memory (i.e., ROM 602) or loaded from storage unit 608 into random access memory (i.e., RAM 603). The RAM 603 may also store various programs and data required for the operation of the electronic device 600. The CPU 601, ROM 602, and RAM 603 are interconnected via bus 604. An input / output interface (i.e., I / O interface 605) is also connected to bus 604.

[0051] Multiple components in electronic device 600 are connected to I / O interface 605, including: input unit 606, output unit 607, and storage unit 608. CPU 601 executes the various methods and processes described above, such as executing method 100. For example, in some embodiments, method 100 may be implemented as a computer software program stored on a machine-readable medium, such as storage unit 608. In some embodiments, part or all of the computer program may be loaded and / or installed on electronic device 600 via ROM 602 and / or communication unit 609. When the computer program is loaded into RAM 603 and executed by CPU 601, one or more operations of method 100 described above may be performed. Alternatively, in other embodiments, CPU 601 may be configured to execute one or more actions of method 100 by any other suitable means (e.g., by means of firmware).

[0052] It should be further noted that the present invention can be a method, apparatus, system, and / or computer program product. A computer program product may include a computer-readable storage medium having computer-readable program instructions loaded thereon for performing various aspects of the present invention.

[0053] Computer-readable storage media can be tangible devices capable of holding and storing instructions for use by an instruction execution device. Computer-readable storage media can be, for example, but not limited to, electrical storage devices, magnetic storage devices, optical storage devices, electromagnetic storage devices, semiconductor storage devices, or any suitable combination thereof. More specific examples (a non-exhaustive list) of computer-readable storage media include: portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), static random access memory (SRAM), portable compact disc read-only memory (CD-ROM), digital multifunction disc (DVD), memory sticks, floppy disks, mechanical encoding devices, such as punch cards or recessed protrusions storing instructions thereon, and any suitable combination thereof. The computer-readable storage media used herein are not to be construed as transient signals themselves, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through waveguides or other transmission media (e.g., light pulses through fiber optic cables), or electrical signals transmitted through wires.

[0054] The computer-readable program instructions described herein can be downloaded from computer-readable storage media to various computing / processing devices, or downloaded via a network, such as the Internet, local area network, wide area network, and / or wireless network, to an external computer or external storage device. The network may include copper transmission cables, fiber optic transmission, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge servers. A network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards them to the computer-readable storage media in the respective computing / processing device.

[0055] The computer program instructions used to perform the operations of this invention may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, state setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Smalltalk, C++, etc., and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The computer-readable program instructions may be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving a remote computer, the remote computer may be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or may be connected to an external computer (e.g., via the Internet using an Internet service provider). In some embodiments, electronic circuitry, such as programmable logic circuitry, field-programmable gate arrays (FPGAs), or programmable logic arrays (PLAs), is personalized by utilizing state information from the computer-readable program instructions. This electronic circuitry can execute the computer-readable program instructions to implement various aspects of the invention.

[0056] Various aspects of the present invention are described herein with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer-readable program instructions.

[0057] These computer-readable program instructions can be provided to a processor in a voice interaction device, a general-purpose computer, a special-purpose computer, or a processing unit of another programmable data processing device, thereby producing a machine such that, when executed by the processing unit of the computer or other programmable data processing device, these instructions create means for implementing the functions / actions specified in one or more blocks of the flowchart and / or block diagram. These computer-readable program instructions can also be stored in a computer-readable storage medium that causes a computer, programmable data processing device, and / or other device to operate in a particular manner; thus, the computer-readable medium storing the instructions comprises an article of manufacture that includes instructions for implementing aspects of the functions / actions specified in one or more blocks of the flowchart and / or block diagram.

[0058] Computer-readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device to cause a series of operational steps to be performed on the computer, other programmable data processing apparatus, or other device to produce a computer-implemented process, thereby causing the instructions executed on the computer, other programmable data processing apparatus, or other device to perform the functions / actions specified in one or more boxes of a flowchart and / or block diagram.

[0059] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of devices, methods, and computer program products according to various embodiments of the present invention. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of an instruction containing one or more executable instructions for implementing a specified logical function. In some alternative implementations, the functions marked in the blocks may occur in a different order than those shown in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, may be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.

[0060] The various embodiments of the present invention have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or technical improvements to the embodiments in the market, or to enable others skilled in the art to understand the embodiments disclosed herein.

[0061] The above are merely optional embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for reducing noise in a hair dryer, the hair dryer comprising a motor and a power supply unit having a rectifier circuit, the motor comprising a stator and a rotor, and the motor rotating at a speed of 100,000 revolutions per minute or more, the method comprising: Detect the output voltage of the rectifier circuit; Determine whether the output voltage is less than a threshold; In response to the output voltage being less than a threshold, the back electromotive force of the motor is controlled to be less than or equal to the output voltage. The threshold value is the back electromotive force of the motor or the maximum value of the back electromotive force of the motor. Controlling the back electromotive force of the motor to be less than or equal to the output voltage includes: reducing the stator current component of the motor on the d-axis.

2. The method according to claim 1, further comprising: Calculate the d-axis components of the motor's stator inductance and stator current. Get the motor speed; The back electromotive force is determined based at least on the components of the stator inductance on the d-axis, the components of the stator current on the d-axis, and the motor speed.

3. The method of claim 2, wherein determining the back electromotive force comprises: The back electromotive force is determined based on the stator inductance component on the d-axis, the stator current component on the d-axis, the motor speed, and a predetermined back electromotive force coefficient.

4. The method according to claim 1, wherein reducing the stator current component of the motor in the d-axis comprises: The stator current component on the d-axis is reduced by setting the stator voltage component of the motor on the d-axis.

5. A computer-readable storage medium having a computer program stored thereon, the computer program, when executed by a machine, implementing the method of any one of claims 1-4.

6. A control device for a hair dryer, the hair dryer comprising a motor and a power supply unit having a rectifier circuit, the motor comprising a stator and a rotor, the control device comprising: A voltage detection unit is configured to detect the output voltage of the rectifier circuit; Control unit; as well as A memory coupled to the control unit and storing instructions for execution by the control unit, which, when executed by the control unit, cause the control device of the hair dryer to perform the steps of the method according to any one of claims 1 to 4.

7. The control device according to claim 6, wherein the voltage detection unit (201) includes a voltage divider resistor.

8. A hair dryer, comprising: An electric motor, the electric motor comprising a stator and a rotor; The power supply unit has a rectifier circuit; as well as The control device according to any one of claims 6-7.

Images