hand dryer

Abstract

The present invention discloses a hand dryer. The hand dryer comprises a housing, the housing being provided with an air outlet, and an air duct leading to the air outlet formed within the housing. The housing also houses a circuit board, a motor electrically connected to at least one of the circuit boards, and fan blades driven by the motor. The at least one circuit board is disposed within the air duct and arranged to divide the air duct into at least two sub-ducts, each of which extends along the direction of the air duct and communicates with the air outlet. Compared with the prior art, the hand dryer is smaller in size and reduces noise.

Description

Technical field

[0001] The present invention relates to electrical appliances, in particular to a hand dryer. [Background Technology]

[0002] Hand dryers are generally classified into two types: heating-type and high-speed air-drying types. Each type has its own unique characteristics. Heating-type hand dryers typically have high heating power, exceeding 1000W, while using a very low motor power of less than 200W. This type of hand dryer typically features high air temperatures, relying on the high-temperature air to remove moisture from the hands. This method of hand drying is relatively slow, typically taking over 30 seconds.

[0003] High-speed hand dryers are characterized by very high wind speeds, reaching over 130 m / s, drying hands in around 10 seconds. Their heating power is also relatively low, at only a few hundred watts. The heating function is solely for comfort and has little impact on drying speed. They are generally used in office buildings and public spaces and are wall-mounted.

[0004] The hand dryer housing houses a motor, fan, and a circuit board with various electrical components. The motor rotates to draw air from the fan into the air duct. To allow the fan-generated air to flow out through the duct, existing hand dryers incorporate guide vanes within the duct. This results in large overall size and high cost for existing high-speed hand dryers. Furthermore, the swirling airflow through the duct creates a high level of noise. The hand dryer also takes up a significant amount of space when in use.

[0005] Therefore, it is necessary to improve the prior art to overcome the above defects. [Summary of the invention]

[0006] An object of the present invention is to provide a hand dryer which has a small size and reduces noise.

[0007] The purpose of the present invention is achieved through the following technical solutions:

[0008] An embodiment of the present invention provides a hand dryer, which has a shell, the shell is provided with an air outlet, an air duct leading to the air outlet is formed in the shell, and the shell also accommodates a circuit board, a motor electrically connected to at least one of the circuit boards, and fan blades driven by the motor. At least one of the circuit boards is arranged in the air duct and is arranged to divide the air duct into at least two sub-air ducts, wherein each of the sub-air ducts extends along the extension direction of the air duct and is connected to the air outlet.

[0009] In one embodiment, the circuit board that divides the air duct into at least two sub-air ducts extends axially along the air duct.

[0010] In one embodiment, the central axis of the output shaft of the motor and the circuit board extending in the axial direction of the air duct are located in the same plane.

[0011] In one embodiment, the circuit board is arranged above the air outlet or below the air outlet.

[0012] In one embodiment, the hand dryer includes at least two circuit boards arranged separately.

[0013] In one embodiment, at least one of the circuit boards is arranged above another of the circuit boards.

[0014] In one embodiment, at least one of the circuit boards is arranged on the inner side of the air outlet at an angle relative to a plane perpendicular to the axial direction of the air duct.

[0015] In one embodiment, the minimum distance between the two circuit boards ranges from 3.6 mm to 4.2 mm.

[0016] In one embodiment, the distance between the two circuit boards gradually increases toward the air outlet.

[0017] In one embodiment, the circuit boards are all arranged in the air duct.

[0018] In one embodiment, at least one of the circuit boards is a power board, and at least another of the circuit boards is a main control board; the power board is electrically connected to the motor, and the main control board is electrically connected to the motor.

[0019] In one embodiment, the main control board is arranged on the inner side of the air outlet at an angle relative to a plane perpendicular to the axial direction of the air duct.

[0020] In one embodiment, the main control board includes at least two sub-circuit boards spaced apart from each other.

[0021] In one embodiment, the two sub-circuit boards are parallel to each other.

[0022] In one embodiment, the main control board is circular, and the power board is rectangular.

[0023] In one embodiment, a power component is provided on at least one of the circuit boards, and the power component is arranged on a side of the circuit board facing the air duct.

[0024] In one embodiment, the housing includes an upper housing and a lower housing, wherein the motor and the fan blades are accommodated in the lower housing, and at least one circuit board is accommodated in the upper housing.

[0025] In one embodiment, the air duct is arranged in the upper shell; the upper shell is in fluid communication with the lower shell; and an air inlet communicating with the air duct is provided on the lower shell.

[0026] In one embodiment, the main control board, the power board, the motor, and the fan blades are arranged from top to bottom.

[0027] In one embodiment, the shell further includes at least one side branch shell, and the side branch shell is provided with an exhaust hole communicating with the air outlet, and the side branch shell is arranged at a preset angle to the shell.

[0028] In one embodiment, the hand dryer is a stand-alone device.

[0029] Compared to existing technologies, this invention offers the following advantages: By placing a circuit board within the air duct, the duct is divided into two sub-ducts, diverting the airflow within the duct. This eliminates air swirl, directing the airflow into two uniform, upward streams, and reducing noise. Furthermore, by placing the circuit board directly within the duct, it eliminates the need for additional space within the housing, further reducing the size of the hand dryer, making it more compact and lowering costs. This also reduces the space required for placement of the hand dryer, making it more convenient to use.

Brief Description of the Drawings

[0030] Figure 1 It is a perspective view of a hand dryer according to an embodiment of the present invention.

[0031] Figure 2 2 is a schematic diagram of the internal structure of a hand dryer according to an embodiment of the present invention.

[0032] Figure 3 yes Figure 1 Cross-sectional view of AA in the figure.

[0033] Figure 4 This is a schematic diagram of a first layout of two circuit boards of the hand dryer of the present invention.

[0034] Figure 5 1 is a schematic diagram of a second layout of two circuit boards of a hand dryer according to an embodiment of the present invention.

[0035] Figure 6 2 is a schematic diagram of a third layout of two circuit boards of a hand dryer according to an embodiment of the present invention.

[0036] Figure 7 2 is a schematic diagram of a fourth layout of two circuit boards of a hand dryer according to an embodiment of the present invention.

[0037] Figure 8 2 is a schematic diagram of a fifth layout of two circuit boards of a hand dryer according to an embodiment of the present invention.

[0038] Figure 9 FIG. 4 is a circuit module diagram of a hand dryer according to an embodiment of the present invention.

[0039] Among them, 100, hand dryer; 1, shell; 11, upper shell; 12, lower shell; 110, air outlet; 13, branch shell; 131, exhaust vent; 141, exhaust vent; 14, branch shell; 3, motor; 4, fan blades; 2, air duct; 21, sub-air duct; 22, sub-air duct; 5, circuit board; 6, circuit board; 61, power element; 7, receiving base; 121, air inlet; 120, air inlet channel. [Specific implementation method]

[0040] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, each embodiment of the present invention will be described in detail below with reference to the accompanying drawings. However, those skilled in the art will appreciate that in each embodiment of the present invention, many technical details are provided to help readers better understand the present application. However, even without these technical details and various changes and modifications based on the following embodiments, the technical solutions claimed in the present application can still be implemented.

[0041] In the following description, for the purpose of illustrating the various disclosed embodiments, certain specific details are set forth in order to provide a thorough understanding of the various disclosed embodiments. However, those skilled in the relevant art will recognize that the embodiments may be practiced without one or more of these specific details. In other cases, well-known devices, structures, and techniques associated with this application may not be shown or described in detail to avoid unnecessarily obscuring the description of the embodiments.

[0042] Unless the context requires otherwise, throughout the specification and claims, the word "comprise" and variations such as "include" and "have" should be construed as having an open, inclusive meaning, ie, should be interpreted to mean "including, but not limited to."

[0043] The following will describe in detail various embodiments of the present invention in conjunction with the accompanying drawings to provide a clearer understanding of the objectives, features and advantages of the present invention. It should be understood that the embodiments shown in the accompanying drawings are not intended to limit the scope of the present invention, but are only intended to illustrate the essential spirit of the technical solution of the present invention.

[0044] Reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, the appearances of "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any manner in one or more embodiments.

[0045] As used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. It should be noted that the term "or" is generally employed in its sense including "and / or" unless the context clearly dictates otherwise.

[0046] In the following description, in order to clearly show the structure and working mode of the present invention, many directional words will be used for description, but words such as "front", "back", "left", "right", "outside", "inside", "outward", "inward", "up", and "down" should be understood as convenient terms and should not be understood as restrictive terms.

[0047] The following describes embodiments of the present invention with reference to the accompanying drawings. Figure 1 and Figure 2 As shown, the hand dryer 100 comprises a housing 1. The housing 1 comprises an upper housing 11, a lower housing 12, and two branch housings 13 and 14 connected to the upper housing 11. The upper housing 11 is positioned above the lower housing 12. The upper and lower housings 11 and 12 are cylindrical structures with a hollow space. It is understood that the housing 1 is not limited to a structure consisting of a spliced ​​upper and lower housing. It can also be a spliced ​​left and right part, or a one-piece housing with a partition layer inside the housing to separate the interior of the housing into two accommodating chambers.

[0048] In this embodiment, the shell 1 includes an upper shell 11 and a lower shell 12 as an example for specific explanation. The upper shell 11 and the lower shell 12 are roughly cylindrical, and it should be understood that they can also be other shapes. Each shell can be made of plastic, or a combination of plastic and metal, or any suitable material. The two side branch shells are respectively located on both sides of the upper shell 11 and are arranged at a preset angle. The angle between the two side branch shells can be 180°, 160° or 150°, etc. Exhaust ports 131 and 141 are respectively provided on the side branch shell 13 and the side branch shell 14, and air outlet channels are respectively provided in the side branch shell 13 and the side branch shell 14. The exhaust port is connected to the corresponding air outlet channel. As a result, wind can flow through the air outlet channel and blow out from the exhaust port.

[0049] The upper shell 11 and the lower shell 12 are fluidically connected to each other and fixed to each other by self-tapping screws, and a sealing ring is provided at the joint of the upper shell 11 and the lower shell 12. In another embodiment, the upper shell 11 and the lower shell 12 can be fixedly connected to each other by a threaded connection method or a snap-on method. An air outlet 110 is provided on the side wall of the upper shell 11 and passes through it, and the air outlet 110 is connected to the air duct 2. The air outlet 110 is located at the upper part of the side wall of the upper shell 11. The air outlet 110 is an elongated opening. An air duct 2 is formed in the upper shell 11 and is fluidically connected to the air outlet 110. The air duct 2 extends from bottom to top to the air outlet 110. The wind generated by the fan blades 4 can flow to the air outlet 110 through the air duct 2 and be blown out from the air outlet.

[0050] The lower shell 12 contains a motor 3 and fan blades 4 driven by the motor 3, and the motor 3 and the fan blades 4 are in the upper shell 11. An air inlet 121 is provided at the bottom of the lower shell 12, and the lower shell 12 is provided with an air inlet channel 120, and the air inlet 121 is connected to the air inlet channel 120. The motor 3 drives the fan blades 4 to rotate, allowing the gas to enter the air inlet channel 120 from the air inlet 121, forming a high-speed airflow into the air duct 2, and then flows from the air outlet 110 into the air outlet channel of the side branch shell, and finally the air is discharged through the exhaust ports on the two side branch shells. It can be understood that there can be only one side branch shell, or three side branch shells can be provided. In another embodiment, a side branch shell can be connected to the upper shell 11, and other air outlet shells can be extended in different directions on the side branch shell according to the requirements of the air outlet direction. The other various structures of the hand dryer will not be described in detail here.

[0051] like Figure 1 、 Figure 2 and Figure 3 As shown, the circuit board 5 is arranged within the air duct 2, below the air outlet 110, and the circuit board 6 is positioned inside the air outlet 110. The circuit board 5 divides the air duct 2 into a sub-duct 21 and a sub-duct 22. Both sub-ducts extend along the direction of the air duct 2 and communicate with the air outlet 110. The circuit board 5 can extend within the air duct 2 at an angle to the axis of the air duct 2 or parallel to the axis of the air duct 2. This eliminates the need for the circuit board 5 to occupy additional space within the housing 1, saving space. This allows for a more compact hand dryer. Furthermore, since the circuit board 5 is directly within the air duct 2, heat dissipation from the various components on the circuit board 5 is facilitated. Furthermore, the circuit board 5 acts as a diverter within the air duct 2, diverting the airflow into two upward-flowing streams, each passing through the sub-duct 21 and the sub-duct 22. This eliminates airflow swirl and reduces noise. It is understood that multiple circuit boards can be positioned within the air duct 2. It is also understood that the circuit board 5 can be positioned against the sidewall of the air duct 2.

[0052] As can be seen from the above, the separate placement of the circuit boards and motor allows for a more rational layout of the circuit boards and motor within the housing, effectively utilizing the space within the housing and reducing space waste. This, in turn, reduces the size of the hand dryer, making it more compact and lowering costs. This also reduces the placement space required for the hand dryer during use, making it more convenient. Furthermore, the circuit boards are positioned away from the air inlet duct 120, thereby undisturbed the air intake area of ​​the air inlet duct 120, reducing wind resistance, lowering noise, and improving air intake efficiency.

[0053] Alternatively, as Figure 2 and Figure 3As shown, the circuit board 5 extends axially along the air duct 2. In this case, the circuit board 5 is parallel to the axis of the air duct 2, allowing airflow from both sub-air ducts to flow smoothly from the air outlet 110 into the corresponding outlet channel. Furthermore, the central axis of the output shaft of the motor 3 can be coplanar with the circuit board 5 extending axially within the air duct 2, thereby more evenly dividing the airflow into two streams. The air duct 2 can be cylindrical, which can better accommodate the circuit board 5 and ensure smoother airflow. Of course, the air duct 2 can also have other shapes, such as a rectangular parallelepiped or a spherical shape.

[0054] Preferably, if Figure 2 and Figure 3 As shown, the central axis of the motor 3's output shaft is coaxial with the axis of the air duct 2. The plane where the circuit board 5 lies divides the air outlet 110 into two sections. The two sections of the air outlet 110 are connected to two sub-air ducts of equal size. In other words, the circuit board 5 evenly divides the air duct 2 into two sections. This allows airflow to flow more evenly from both sides of the hand dryer. This also improves the balance of the two sides of the hand dryer, facilitating its stable placement.

[0055] In some embodiments, the central axis of the output shaft of the motor 3 may also deviate from the circuit board 5 extending axially along the air duct 2 .

[0056] Furthermore, if Figure 2 and Figure 3 As shown, the housing 1 also houses a separate circuit board 6 and a circuit board 5, each with different functions. Both circuit boards 6 and 5 are located within the housing 1, with circuit board 6 positioned above circuit board 5 and inside the air outlet 110. Thus, the airflow from the air duct 2 can be guided toward the air outlet 110 via circuit board 6. More specifically, circuit board 6 is arranged inside the air outlet 110 at an angle relative to a plane perpendicular to the axial direction of the air duct 2. Preferably, the distance between the two circuit boards gradually increases toward the air outlet 110, meaning that circuit board 6 is tilted upward toward the side of the air outlet 110.

[0057] Since the circuit board 6 is provided with a plurality of circuit elements, or the circuit board 6 is placed in different orientations, the distances between each point on the circuit board 6 and the circuit board 5 may be at least partially different. Figure 4As shown, the minimum distance h between circuit boards 5 and 6 ranges from 3.6mm to 4.2mm, such as 3.8mm, 3.9mm, or 4.0mm. Furthermore, the longitudinal distance M between the top edge of circuit board 6 and the top of the housing cavity satisfies the condition 3.8mm≤h≤(M-3.5mm), where 3.8mm represents the minimum distance between circuit boards 5 and 6, and 3.5mm at the top edge of circuit board 6 represents the minimum safe creepage clearance. This minimum distance between the separated circuit boards 5 and 6 ensures a safe distance between them, prevents remixing of the previously separated airflows and causes energy loss, and meets the requirements of miniaturization.

[0058] like Figure 2 and Figure 3 As shown, circuit board 6 is circular, while circuit board 5 is rectangular. Hooks are provided on the inner wall of the upper housing 11, and the circuit boards have latches that engage with the hooks, securing the boards to the upper housing 11. In another embodiment, the two circuit boards can be fastened to the upper housing 11 using bolts. The circular circuit boards avoid right-angled airflow and minimize flow losses.

[0059] Alternatively, as Figure 2 、 Figure 3 and Figure 9 As shown, circuit board 6 is the main control board, and circuit board 5 is the power board. The power board is electrically connected to the motor 3 and the main control board, and supplies power to the main control board and the power board. The main control board is electrically connected to the motor 3, so that the power supply is supplied to the main control board and the motor 3 respectively through the power board. The main control board can control the working state of the motor, such as heat, wind speed, working time, etc. By controlling the motor through the main control board, it is also possible to match a higher-power motor and increase the wind speed. In addition, a relatively large capacitor is provided on the power board, and the power board takes up more space. Placing it in the air duct 2 can make the space planning in the housing 1 more reasonable. At the same time, the power board generates more heat, and placing it in the air duct 2 is more conducive to its heat dissipation.

[0060] It is understandable that the circuit board 6 and the circuit board 5 may also be other types of circuit boards, at least one of which controls the motor 3. Alternatively, in addition to the circuit board 6 and the circuit board 5, other circuit boards may be used to control the motor 3, and the motor 3 is not limited to being controlled only by the main control board.

[0061] Several circuit components are provided on the side of the main control board (i.e., circuit board 6) facing the power board (i.e., circuit board 5), at least some of which are power components 61, such as IGBT (or high-voltage MOS), driver chips, and MCUs. These power components are placed on the side of the main control board (i.e., circuit board 6) facing the power board (i.e., circuit board 5), and are placed at one end near the air outlet 110, so that the airflow flowing out of the air duct 2 can blow towards the power components 61, allowing the power components 61 to dissipate heat more effectively. At this time, within the housing 1, the main control board (i.e., circuit board 6), the power board (i.e., circuit board 5), the motor 3, and the fan blades 4 are arranged from top to bottom. The airflow formed by the fan blades 4 flows sequentially from bottom to top through the power board (i.e., circuit board 5) and the main control board (i.e., circuit board 6), dissipating heat. It is understandable that power components can also be provided on other circuit boards, and the power components are arranged on the side of the circuit board facing the air duct 2, so that the airflow in the air duct 2 can flow through the power components, dissipating heat from the power components.

[0062] The main control board (i.e., circuit board 6) includes at least two spaced-apart sub-circuits. The two sub-circuits are parallel to each other, one sub-circuit board is located above the other sub-circuit board, and the two sub-circuits are spaced apart from each other. Adhesive tape or an insulating rubber pad may be placed between the two sub-circuits.

[0063] It is understandable that the circuit board 5 can also be the main control board and the circuit board 6 can be the power board. The main control board and the power board can be arranged according to actual needs.

[0064] In addition, in addition to the circuit board 5 and the circuit board 6 , other circuit boards may be arranged in the hand dryer according to usage requirements and placed in the upper shell 11 or the lower shell 12 .

[0065] Furthermore, a portion of the area between the side of the motor 3 and the housing can be left empty to accommodate a circuit board. This circuit board can be used to control the motor 3, connect to a power supply, or house other functional circuit boards. In this case, the volume of the lower housing area of ​​the hand dryer is increased, but the volume of the upper housing area is reduced, allowing the hand dryer to have different sizes and be suitable for different environments.

[0066] Furthermore, each circuit board is separated from the motor 3. It is understandable that the circuit board 5 can also be close to the motor 6.

[0067] It's understood that, in addition to being placed inside the air duct 2 and air outlet 110, the circuit board can also be placed elsewhere according to a reasonable spatial layout, which can also make the internal structure of the hand dryer more compact, as will be further explained below. Furthermore, to allow the drying device to be placed directly on a countertop, a receiving base 7 is connected to the bottom of the lower housing 12, making the hand dryer a standalone device. This allows it to be moved to a suitable location at any time according to usage needs, facilitating cleaning of the hand dryer and the area where it is placed.

[0068] Alternatively, in the hand dryer, the fan blades 4, motor 3, circuit board 5, and circuit board 6 may be arranged sequentially from top to bottom. In this case, the air duct 2 is positioned below the fan blades 4, the air outlet 110 is positioned below the air duct 2, and the circuit board 5 is positioned above the air outlet. A branch housing having an air outlet duct is positioned adjacent to the air outlet 110 and is also positioned below the air duct 2.

[0069] Figure 5-Figure 8 Schematic diagrams showing various different layouts of the circuit board of the hand dryer of the present invention. Figure 5 In the layout shown in FIG. 7 , the circuit board 5 and the circuit board 6 are both arranged in the air duct 2 . In this case, both circuit boards are located below the air outlet 110 .

[0070] like Figure 5 As shown, circuit board 5 divides air duct 2 into sub-duct 21 and sub-duct 22. Circuit board 6 and circuit board 5 are positioned opposite each other, with the duct axis passing between them. This prevents interference between circuit boards 5 and 6, and allows airflow to flow normally along one side of circuit board 5 and 6. It is understood that circuit boards 5 and 6 can also be positioned not in the center of air duct 2 but offset to one side of the duct axis. Adjacent circuit boards can also be separated by foam.

[0071] Alternatively, circuit boards 5 and 6 may be arranged obliquely within air duct 2, each at a certain angle to the duct axis. Airflow may flow from the side of circuit board 6 facing away from the circuit board to air outlet 110, from the side of circuit board 5 facing away from circuit board 6 to air outlet 110, or between circuit boards 5 and 6.

[0072] Alternatively, as Figure 6 As shown, the planes where the circuit boards 5 and 6 are located can be cross-set, and there is a preset angle between the circuit boards 5 and 6, which is a different angle such as 30°, 70°, or 90°.

[0073] Or, as Figure 7As shown, the circuit board 5 and the circuit board 6 are arranged opposite to each other and are both attached to the side wall of the air duct 2, and the air duct 2 is formed between the circuit board 5 and the circuit board 6. It can be understood that the circuit board 5 and the circuit board 6 can also be adjacent and attached along the side wall of the air duct 2.

[0074] It is understandable that the number of circuit boards can be more than 2, and can be 3 or 4, and arranged in different arrangements in the air duct 2. The number of circuit boards can also be 1, arranged in the air duct 2, or arranged at other locations in the housing 1.

[0075] When the air duct 2 is located above the air outlet 110 , all circuit boards are also located above the air outlet, and the circuit boards can be arranged according to the actual shape of the drying setting.

[0076] Figure 8 Another circuit board layout diagram of the hand dryer of the present invention is shown. Figure 8 As shown, the circuit boards 5 and 6 in this hand dryer are arranged inside the air outlet 110, tilted relative to a plane perpendicular to the axial direction of the air duct. Circuit boards 5 and 6 may or may not be parallel to each other. Without circuit boards in the air duct, airflow can flow smoothly. It is understood that there may be more than two circuit boards, perhaps three or four, all of which are located inside the air outlet 110.

[0077] As can be seen from the above embodiments, when at least two circuit boards are provided, the electrical components can be arranged separately on different circuit boards. The volume of a single circuit board is reduced compared to the volume of the circuit board in the original hand dryer. Multiple circuit boards can be arranged within the housing according to the shape of the hand dryer, rationally utilizing the space within the housing and reducing space waste. This can further reduce the size of the hand dryer, making it more compact and reducing costs. During use, the hand dryer also requires less space for placement, making it more convenient to use.

[0078] Furthermore, the hand dryer can be provided with a battery pack, which supplies power to the motor and the circuit boards. Of course, the hand dryer can also be powered by an external power supply.

[0079] These and other changes can be made to the embodiments in light of the above detailed description.In general, in the claims, the terms used should not be construed as limited to the specific embodiments disclosed in the specification and claims, but should be construed to include all possible embodiments along with the full scope of equivalents to which these claims are entitled.

Claims

1. A hand dryer comprising a housing, the housing being provided with an air outlet, an air duct leading to the air outlet being formed in the housing, and the housing further accommodating a circuit board, a motor electrically connected to at least one of the circuit boards, and fan blades driven by the motor, wherein: At least one circuit board is arranged in the air duct and is arranged to divide the air duct into at least two sub-air ducts, wherein each sub-air duct extends along the extension direction of the air duct and is connected to the air outlet; The circuit board for dividing the air duct into at least two sub-air ducts is located below the air outlet and above the motor, and divides the air outlet into two parts, and the two parts of the air outlet are respectively connected to the two sub-air ducts.

2. The hand dryer according to claim 1, characterized in that The circuit board that divides the air duct into at least two sub-air ducts extends axially along the air duct.

3. The hand dryer according to claim 2, characterized in that The central axis of the output shaft of the motor and the circuit board extending in the axial direction of the air duct are located in the same plane.

4. The hand dryer according to claim 3, characterized in that The hand dryer includes at least two circuit boards that are arranged separately.

5. The hand dryer according to claim 4, characterized in that: At least one of the circuit boards is arranged above another of the circuit boards.

6. The hand dryer according to claim 4, characterized in that At least one of the circuit boards is arranged on the inner side of the air outlet at an angle relative to a plane perpendicular to the axial direction of the air duct.

7. The hand dryer according to claim 5, characterized in that The minimum distance between the two circuit boards ranges from 3.6 mm to 4.2 mm.

8. The hand dryer according to claim 6, characterized in that The distance between the two circuit boards gradually increases toward the air outlet.

9. The hand dryer according to claim 4, characterized in that The circuit boards are all arranged in the air duct.

10. The hand dryer according to claim 4, characterized in that At least one of the circuit boards is a power board, and at least another of the circuit boards is a main control board; the power board is electrically connected to the motor, and the main control board is electrically connected to the motor.

11. The hand dryer according to claim 10, characterized in that The main control board is arranged on the inner side of the air outlet at an angle relative to a plane perpendicular to the axial direction of the air duct.

12. The hand dryer according to claim 10, characterized in that The main control board includes at least two sub-circuit boards spaced apart from each other.

13. The hand dryer according to claim 12, characterized in that The two sub-circuit boards are parallel to each other.

14. The hand dryer according to claim 10, characterized in that The main control board is circular, and the power board is rectangular.

15. The hand dryer according to claim 1, characterized in that At least one of the circuit boards is provided with a power element, and the power element is arranged on a side of the circuit board facing the air duct.

16. The hand dryer according to claim 1, characterized in that The housing includes an upper housing and a lower housing, wherein the motor and the fan blades are accommodated in the lower housing, and at least one circuit board is accommodated in the upper housing.

17. The hand dryer according to claim 16, characterized in that The air duct is arranged in the upper shell; the upper shell is in fluid communication with the lower shell; and an air inlet communicating with the air duct is opened on the lower shell.

18. The hand dryer according to claim 11, characterized in that The main control board, the power board, the motor, and the fan blades are arranged from top to bottom.

19. The hand dryer according to claim 1, characterized in that The shell further includes at least one side branch shell, and an exhaust hole communicating with the air outlet is opened on the side branch shell, and the side branch shell is arranged at a preset angle with the shell.

20. The hand dryer according to claim 1, characterized in that The hand dryer is an independent device.

Images