Low-noise hair drier
By adopting a combined structure of the inner air duct and the outer air duct and the air guide column design in a high-speed hair dryer, the air flow diffusion is guided by the expansion section, which solves the air flow disorder and noise problems, and achieves the air uniformity and noise reduction in the air outlet section .
Patent Information
- Application Number
- CN202420149174.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-01-22
- Publication Date
- 2024-12-10
- Estimated Expiration
- 2034-01-22
AI Technical Summary
The existing high-speed hair dryer has installed air inlets in the inner recess of the front cover of the machine head, causing air flow to be chaotic and increasing noise, and the inner recessed air duct fails to effectively guide the air flow, so that the air flow forms a low-pressure zone in the middle of the air outlet section, increasing turbulence. Increase noise.
A low-noise hair dryer is designed, adopting a combined structure of an inner air duct and an outer air duct, where the inner air duct has an air inlet and an air outlet, and the inner diameter of the air inlet is larger than the air inlet, forming an expansion section to guide the air flow to diffuse and pass through the air guide The column guides the airflow into the outer air duct to reduce airflow disorder.
Through the guidance of the expansion section, the airflow forms a uniform airflow in the middle of the outlet section, reducing noise, and improving the uniformity and stability of the airflow, reducing turbulence, and improving the air uniformity of the outlet section.
Smart Images
Figure CN222129589U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of hair dryers, and in particular to a low-noise hair dryer. Background Art
[0002] Existing high-speed hair dryers usually have an annular air outlet on the front cover of the head to pressurize and speed up the airflow and make the blown airflow form a uniform cylindrical shape. The area on the front cover of the head of the existing high-speed hair dryer surrounded by the annular air outlet is usually also provided with an inner recessed portion sunken into the body, and the space in the inner recessed portion is connected to the middle area near the central axis of the air outlet section outside the front cover of the head. After the head of the machine discharges the airflow through the annular air outlet, the airflow is initially in the outer annular area of the air outlet section corresponding to the annular air outlet. The airflow will converge to form a cylindrical airflow only after traveling a certain distance. However, in the air outlet section close to the head of the machine, the airflow has just been discharged from the annular air outlet and has not yet converged to form a cylindrical airflow. There is a high-speed airflow in the outer area of the air outlet section, while the middle area of the air outlet section is surrounded by the outer high-speed airflow, resulting in a large difference in air velocity between the outer area and the middle area of the air outlet section, forming a low-pressure area in the middle area, and part of the airflow in the outer high-speed airflow will enter the middle area to form turbulence. Since the space in the inner recessed portion is connected to the middle area of the air outlet section to form the same space, the middle turbulent space is increased, the turbulence in the middle turbulent space is increased, the air vibration is intensified, and the noise is increased.
[0003] At present, there are high-speed hair dryers that have an air inlet on the inner concave part of the front cover of the head, so that part of the airflow in the head enters the space surrounded by the inner concave part through the air inlet and continues to be discharged forward. At this time, the space surrounded by the inner concave part becomes the inner concave part air duct. This part of the airflow enters the middle area of the air outlet section, which can reduce the pressure difference between the middle area and the peripheral high-speed airflow area, reduce the turbulence formed by the peripheral high-speed airflow entering the middle area, and thus reduce the noise. However, the inner concave part air duct is straight-cylindrical and roughly U-shaped as a whole to correspond to the middle area of the air outlet section, so the sizes of the inner concave part air duct and the air outlet are relatively large; and the air inlet is arranged on the bottom surface of the inner concave part. Since most of the airflow still needs to be blown out from the air outlet outside the inner concave part to ensure the performance of the high-speed hair dryer, only a small part of the airflow in the head is blown out from the inner concave part air duct, so the size of the air inlet on the inner concave part is relatively small. In this way, the process of airflow entering the inner recessed air duct through the air inlet is that a small amount of airflow instantly enters a large space through the small hole, and the smaller air inlet speeds up the airflow, so that the main tendency of the airflow is to move directly forward. When the airflow enters the inner recessed air duct, the inner diameter of the space where it is located instantly increases significantly, and the inner recessed air duct does not guide the airflow, so that the airflow still mainly moves according to its own flow trend and cannot be diffused more evenly in the inner recessed air duct, and part of the airflow randomly diffuses into the surrounding space to form chaotic turbulence, which causes the airflow to be more chaotic after being blown out from the air outlet of the inner recessed air duct, and still aggravates the noise. Utility Model Content
[0004] The utility model makes improvements on the problems existing in the above-mentioned prior art, that is, the purpose of the utility model is to provide a low-noise hair dryer, which can reduce the noise in the middle area near the central axis of the air outlet section outside the head.
[0005] The low-noise hair dryer of the utility model comprises a head with an air outlet and an air duct arranged in the head, the air duct comprises an inner air duct and an outer air duct arranged on the periphery of the inner air duct, the inner air duct and the outer air duct are both connected to the air inlet end of the head, the outer air duct is connected to the air outlet, the inner air duct has an air inlet and an air outlet with an inner diameter larger than the air inlet, and the inner diameter of at least part of the inner air duct increases from the air inlet end to the air outlet end, forming a flow expansion section to guide the airflow to diffuse toward the air outlet.
[0006] In one embodiment, the minimum inner diameter of the air inlet end of the expansion section is consistent with the inner diameter of the air inlet, and the maximum inner diameter of the air outlet end is consistent with the inner diameter of the air outlet, so that the expansion section guides the airflow to spread to cover the air outlet.
[0007] In one embodiment, the outlet end of the expansion section extends to the outlet or is connected to the outlet by a straight section whose inner diameter is consistent with the inner diameter of the outlet, and / or the inlet end of the expansion section extends to the inlet or is connected to the inlet by a straight section whose inner diameter is consistent with the inner diameter of the inlet.
[0008] In one embodiment, the flow expansion section includes more than two small flow expansion sections, and the more than two small flow expansion sections are arranged continuously, at intervals, or staggered along the flow direction of the airflow in the inner air duct.
[0009] In one embodiment, the inner air duct is a flow expansion section from the air inlet to the air outlet, so that the airflow from the air inlet to the air outlet is always guided and diffused by the flow expansion section.
[0010] In one embodiment, the air inlet and the air outlet are coaxially arranged along the flow direction of the airflow in the inner air duct, so that the inner diameter of the expansion section increases toward the periphery to guide the airflow to diffuse toward the periphery.
[0011] In one embodiment, the inner diameter of the expansion section gradually increases from the air inlet end to the air outlet end.
[0012] In one embodiment, the expansion section is a conical air duct, and the inner conical surface faces the air outlet.
[0013] In one embodiment, it also includes an air guide column arranged at the air inlet end of the head, which extends along the flow direction of the air flow in the air duct and blocks the air inlet of the inner air duct, so that most of the air flow is blocked by the outer wall of the air guide column and enters the outer air duct.
[0014] In one embodiment, the air guide column at least partially extends into the air inlet of the inner air duct, and the air guide column is spaced apart from the inner edge of the air inlet, so that part of the air flow enters the inner air duct along the outer wall of the air guide column.
[0015] Beneficial effects:
[0016] 1) After being guided and diffused by the expansion section, the airflow in the inner air duct of the utility model is diffused toward the air outlet from the small area airflow that was originally limited to the vicinity of the central axis of the air inlet when entering the inner air duct through the air inlet, to a uniform large area airflow. On the one hand, the coverage of the middle area of the air outlet section by the airflow is improved, so that as much airflow as possible is blown out from the middle area of the air outlet section, so that most of the middle area of the air outlet section can have a uniform airflow, thereby improving the air uniformity in the middle area of the air outlet section and reducing noise. On the other hand, guiding and diffusing the airflow can improve the uniformity of the airflow itself, avoid the airflow from diffusing at will and causing disorder, thereby reducing noise.
[0017] 2) In one embodiment of the utility model, the minimum inner diameter of the air inlet end of the expansion section is consistent with the inner diameter of the air inlet and the maximum inner diameter of the air outlet end is consistent with the inner diameter of the air outlet. The inner diameter size of the expansion section itself increases from the size of the air inlet to the size of the air outlet. There is no need for the rest of the internal air duct to compensate for the size deviation, so that the expansion section can directly correspond to and receive the airflow flowing out of the air inlet, and the expansion section can directly guide the airflow to diffuse to cover the air outlet, thereby achieving the purpose of smoothly and gently guiding the airflow to diffuse only by the expansion section.
[0018] 3) In one embodiment of the utility model, the change in the inner diameter of the inner air duct is only caused by the expansion section. When only a part of the inner air duct is the expansion section, the remaining sections of the inner air duct are straight sections with unchanged inner diameters, thereby avoiding the random diffusion or reverse contraction of the airflow in the absence of proper guidance, thereby reducing the turbulence of the airflow itself to reduce noise.
[0019] 4) In one embodiment of the utility model, the inner air duct is a flow expansion section from the air inlet to the air outlet. The airflow is always guided and diffused by the flow expansion section in the inner air duct. The degree of diffusion of the airflow in the inner air duct from the air inlet to the air outlet per unit flow distance is reduced, thereby further improving the stability and uniformity of the airflow diffusion, further reducing the turbulence of the airflow, and further reducing the noise. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] In order to more clearly illustrate the technical solution of the embodiments of the present application, the drawings required for use in the embodiments of the present application are briefly introduced below.
[0021] Figure 1 is a cross-sectional view of the nose;
[0022] Figure 2 is a three-dimensional schematic diagram of the machine head;
[0023] Figure 3 is a schematic diagram of an improved embodiment of the wind guide column;
[0024] Figure 4 is a schematic diagram of the low-noise hair dryer;
[0025] Figure numerals: 1. head, 11. air outlet, 2. inner air duct, 21. air inlet, 22. air outlet, 3. outer air duct, 4. air guide column, 5. heating element, 6. handle. DETAILED DESCRIPTION
[0026] The following specific embodiments are merely explanations of the present application and are not limitations of the present application. After reading this specification, those skilled in the art may make modifications to the embodiments without any creative contribution as needed. However, as long as they are within the scope of the claims of the present application, they are protected by the patent law.
[0027] Figure 1The utility model shows a low-noise hair dryer, comprising a head 1 with an air outlet 11 and an air duct arranged in the head 1, the air duct comprising an inner air duct 2 and an outer air duct 3 sleeved on the outer periphery of the inner air duct 2, the inner air duct 2 and the outer air duct 3 are both connected to the air inlet end of the head 1, and the airflow in the hair dryer enters the head 1 and is discharged outward through the outer air duct 3 and the inner air duct 2, the outer air duct 3 is connected to the air outlet 11, and the airflow discharged from the air outlet 11 through the outer air duct 3 plays a major role in drying hair to exert the main function of the hair dryer, so most of the airflow needs to be discharged through the outer air duct 3, and a small part of the airflow is discharged from the inner air duct 2, wherein the airflow discharged through the outer air duct 3 forms an annular high-speed airflow on the outer periphery of the air outlet section on the outside of the head 1, and the middle area near the central axis of the air outlet section is surrounded by the outer high-speed airflow. The inner air duct 2 has an air inlet 21 and an air outlet 22 whose inner diameter is larger than the air inlet 21. The air inlet 21 is relatively small to prevent the inner air duct 2 from occupying too much airflow, resulting in insufficient airflow in the outer air duct 3. The larger air outlet 22 can correspond to the middle area of the air outlet section outside the head 1. The airflow discharged through the inner air duct 2 enters the middle area of the air outlet section, which can reduce the air pressure difference between the outer area and the middle area of the air outlet section, thereby reducing the generation of turbulence in the middle area of the air outlet section; and in the utility model, the inner diameter of at least part of the inner air duct 2 increases from the air inlet end to the air outlet end, forming a flow expansion section to guide the airflow The airflow diffuses toward the air outlet 22. When the airflow enters the inner air duct 2 through the air inlet 21 and flows through the expansion section, whenever the inner diameter of the expansion section increases to a certain extent, the airflow will adaptively diffuse to a certain extent to fill the expansion section. In this way, as the expansion section continues to increase along the flow direction of the airflow, the airflow can continue to adaptively diffuse to keep the expansion section filled, thereby guiding the small-area airflow passing through the air inlet 21 toward the air outlet 22 to diffuse into a large-area airflow. In addition, the adaptive diffusion of the airflow is soft and uniform under the guidance of the expansion section, and the airflow itself has a high stability, which reduces the turbulence of the airflow itself. Therefore, after the airflow in the inner air duct 2 of the utility model is guided and diffused by the expansion section, it is changed from a small area of airflow limited to the vicinity of the central axis of the air inlet 21 when entering the inner air duct 2 through the air inlet 21 to a uniform large area of airflow diffused toward the air outlet 22. On the one hand, it improves the coverage of the middle area of the air outlet section by the airflow, so that as much airflow as possible is blown out from the middle area of the air outlet section, so that most of the middle area of the air outlet section can have a uniform airflow, thereby improving the air uniformity of the middle area of the air outlet section and reducing noise. On the other hand, guiding and diffusing the airflow can improve the uniformity of the airflow itself, avoid the airflow from diffusing randomly and causing self-disorder, thereby reducing noise. Among them, Figure 2 In a specific embodiment shown, the air outlet 11 on the head 1 is annular, corresponding to the outer air duct 3 surrounding the outer periphery of the inner air duct 2. The air outlet 11 and the outer air duct 3 can both be continuous annular structures or discontinuous annular structures.
[0028] Regarding the specific implementation of the flow expansion section, the inner air duct 2 can be a flow expansion section in the entire section from the air inlet 21 to the air outlet 22, or a partial section from the air inlet 21 to the air outlet 22 can be a flow expansion section. Figure 3 It shows a first embodiment in which the inner air duct 2 is a flow expansion section from the air inlet 21 to the air outlet 22. During the entire process of the airflow traveling in the inner air duct 2, the flow expansion section is always guided and diffused. The increase in the inner diameter of the flow expansion section from its own air inlet end to the air outlet end is completed through the entire inner air duct 2. In this way, the increase in the inner diameter of the flow expansion section is reduced for each unit distance of the airflow flowing from the air inlet 21 to the air outlet 22 in the inner air duct 2, that is, the degree of diffusion of the airflow in the inner air duct 2 from the air inlet 21 to the air outlet 22 is reduced, thereby further improving the stability and uniformity of the airflow diffusion, further reducing the turbulence of the airflow, and further reducing the noise. In the second embodiment in which some sections are expansion sections, the expansion section may have only one section, or may include more than two small expansion sections for guiding and diffusing the airflow respectively. The more than two small expansion sections may be arranged continuously, at intervals, or in an alternating manner along the airflow flow direction in the inner air duct 2, so that the more than two small expansion sections jointly guide the airflow to diffuse continuously, in stages, or locally within a unit time to achieve a total guided diffusion, wherein each small expansion section may be of the same or similar shape, or of different shapes, as long as the inner diameter increases from its own air inlet end to the air outlet end. It can be understood that when there are more than two small expansion sections, the expansion section is a total expansion section composed of the more than two small expansion sections.
[0029] The inner diameter of the air inlet 21 of the inner air duct 2 of the utility model is smaller than the inner diameter of the air outlet 22. The inner diameter of the air inlet 21 is smaller to prevent excessive airflow in the head 1 from entering the inner air duct 2 and excessively weakening the airflow flow of the outer air duct 3, and the air outlet 22 is larger to allow the airflow discharged from the inner air duct 2 to correspond to the middle area of the air outlet section as much as possible; when the airflow enters the inner air duct 2 through the air inlet 21, it is a small area airflow confined to the vicinity of the central axis of the air inlet 21. At this time, the airflow has the weakest coverage ability for the middle area of the air outlet section, and the function of the expansion section of the inner air duct 2 is to guide and diffuse the airflow, so that the airflow is evenly diffused to cover the maximum inner diameter of the air outlet end of the expansion section. At this time, the airflow has a higher degree of coverage of the middle area of the air outlet section, and has a better effect on reducing the noise in the middle area of the air outlet section. In the utility model, the inner air duct 2 as a whole extends from the air inlet 21 to the air outlet 22 along the direction of air flow, wherein the guidance and diffusion of the airflow is achieved only by the expansion section of the inner air duct 2, thereby ensuring a smooth and gentle guidance process and reducing airflow turbulence; if the minimum inner diameter at the air inlet end of the expansion section does not correspond to the inner diameter of the air inlet 21, and the maximum inner diameter at the air outlet end of the expansion section does not correspond to the inner diameter of the air outlet 22, then the connection between the expansion section and the air inlet 21 and between the expansion section and the air outlet 22 requires a sudden change in the inner diameter of the inner air duct 2 to be achieved, thereby compensating for the inner diameter size deviation. The sudden change in the inner diameter of the inner air duct 2 will cause random diffusion of the airflow, resulting in airflow turbulence and noise. Therefore, in one embodiment, the minimum inner diameter of the air inlet end of the expansion section is consistent with the inner diameter of the air inlet 21 and the maximum inner diameter of the air outlet end is consistent with the inner diameter of the air outlet 22. The inner diameter size of the expansion section itself increases from the size of the air inlet 21 to the size of the air outlet 22, and there is no need for the rest of the inner air duct 2 to compensate for the size deviation, so that the expansion section can directly correspond to and receive the airflow flowing out of the air inlet 21, and the expansion section can directly guide the airflow to diffuse to cover the air outlet 22, thereby achieving the purpose of smoothly and gently guiding the airflow to diffuse only by the expansion section.
[0030] In the above embodiment, the air inlet end of the expansion section corresponds to the air inlet 21 and the air outlet end corresponds to the air outlet 22. There is no size deviation. The airflow can be guided and diffused from the air inlet 21 to the air outlet 22 by relying solely on the expansion section. In this case, the guidance and diffusion of the airflow no longer requires the assistance of the rest of the inner air duct 2. Instead, the inner diameter size changes of the remaining sections of the inner air duct 2 except the expansion section should be avoided as much as possible, including the reduction of the inner diameter along the flow direction of the airflow in the inner air duct 2 or the sudden increase or decrease of the inner diameter like a cliff. The inner diameter size changes of the remaining sections are not only unhelpful to the guidance and diffusion of the airflow, but also affect the uniformity and stability of the airflow. Therefore, on the basis of the above-mentioned embodiments of the utility model, further improvements are made, in which the change in the inner diameter of the inner air duct 2 is only caused by the expansion section. When only part of the sections in the inner air duct 2 are expansion sections, the remaining sections of the inner air duct 2 are straight sections with unchanged inner diameters. For example, based on various implementations of the expansion section, the straight section with unchanged inner diameter can be located between adjacent small expansion sections and / or between the expansion section and the air inlet 21 and / or between the expansion section and the air outlet 22, so that when the airflow flows through the part outside the expansion section in the inner air duct 2, the inner diameter of the channel through which the airflow flows will not produce the above-mentioned inner diameter size change, thereby avoiding the random diffusion or reverse contraction of the airflow in the absence of proper guidance, thereby reducing the turbulence of the airflow itself to reduce noise. In the present embodiment, it can be understood that when the total expansion section in the inner air duct 2 includes more than two small expansion sections, the expansion section is the total expansion section. Specifically, it is preferred that the outlet end of the expansion section extends to the air outlet 22 or is connected to the air outlet 22 with a straight section having an inner diameter consistent with the inner diameter of the air outlet 22, so that the airflow flows toward the air outlet 22 after leaving the expansion section, and / or, the inlet end of the expansion section extends to the air inlet 21 or is connected to the air inlet 21 with a straight section having an inner diameter consistent with the inner diameter of the air inlet 21, so that the airflow flows toward the expansion section after passing through the air inlet 21.
[0031] The inner diameter of the expansion section in the utility model increases from the air inlet end to the air outlet end, and the direction in which the inner diameter increases toward the periphery depends on the positional relationship between the air inlet 21 and the air outlet 22. First, there are three embodiments of the positional relationship between the air inlet 21 and the air outlet 22, namely, the projection of the air inlet 21 along the air flow direction in the inner air duct 2 is completely located within the range of the air outlet 22, or is partially located within the range of the air outlet 22, or is not at all within the range of the air outlet 22. Among them, the projection of the air inlet 21 along the air flow direction in the inner air duct 2 is completely located within the range of the air outlet 22, which is a preferred embodiment, which is conducive to the reasonable spatial allocation of the inner air duct 2 and the outer air duct 3 in the head 1, and reduces the influence of the inner air duct 2 on the air flow in the outer air duct 3. In this preferred embodiment, it can be further divided into two specific implementation modes. The first is that the air inlet 21 and the air outlet 22 are eccentrically arranged along the flow direction of the airflow in the inner air duct 2. In this way, the total increase degree of the inner diameter of the expansion section in all directions is inconsistent, which will weaken the uniformity of the airflow guidance and diffusion, weaken the effect of reducing airflow turbulence, and thus weaken the noise reduction effect; therefore, the second implementation mode is preferred, the air inlet 21 and the air outlet 22 are coaxially arranged along the flow direction of the airflow in the inner air duct 2, so that the inner diameter of the expansion section increases in all directions to guide the airflow to diffuse in all directions, and the total increase degree of the inner diameter of the expansion section in all directions is consistent. From the time the airflow enters the expansion section to the time it leaves the expansion section, from the result, the airflow diffuses in all directions and the total diffusion degree is consistent, which further improves the uniformity of the airflow, reduces airflow turbulence and reduces noise. In the present preferred embodiment, the total diffusion degree of the airflow in all directions is limited to be consistent. It can be understood that this is a limitation at both ends from the initial state to the final state, and the process of the inner diameter of the expansion section increasing in all directions along the airflow flow direction in the inner air duct 2 may not be uniform. This is based on the specific shape of the inner wall of the expansion section and the composition shape of the expansion section itself, that is, when the airflow flows in the expansion section, the degree of diffusion of the network in all directions per unit time may be uniform or inconsistent. Even locally, due to the shape of the inner wall of the expansion section, there may be a special situation where the inner diameter of the expansion section does not increase. However, even if such a special situation exists, it does not affect the overall trend and shape of the expansion section from the air inlet end to the air outlet end.
[0032] Furthermore, in one embodiment, the inner diameter of the expansion section gradually increases from the air inlet end to the air outlet end. In this way, the inner diameter of the expansion section always increases from the air inlet end to the air outlet end, avoiding the special situation that the local inner diameter of the expansion section does not increase, further improving the smoothness and softness of the expansion section for airflow guidance, ensuring the continuous diffusion of the airflow in the expansion section, further improving the uniformity of the airflow, reducing airflow turbulence to reduce noise. In this embodiment, it is required that the inner wall of the expansion section has a certain smoothness from the air inlet end to the air outlet end, such as an inclined straight shape, an inclined arc shape, etc. Further, it is preferred that the expansion section is a conical air duct, and the inner cone faces the air outlet 22. In this way, along the airflow flow direction in the inner air duct 2, the degree of increase of the inner diameter of the expansion section in all directions is always uniform, so that when the airflow flows in the expansion section, the degree of diffusion in all directions in any unit time is always uniform, further improving the uniformity of the airflow, thereby reducing noise. Furthermore, Figure 3 It is shown that in a preferred embodiment, the expansion section is a conical air duct, the inner conical surface faces the air outlet 22, and the inner air duct 2 from the air inlet 21 to the air outlet 22 is a expansion section.
[0033] In the utility model, the inner air duct 2 and the outer air duct 3 are both connected to the air inlet end of the head 1, so there is a problem of how to distribute the airflow in the head 1 between the inner air duct 2 and the outer air duct 3. In the utility model, the high-speed airflow output by the low-noise hair dryer is mainly discharged from the air outlet 11 through the outer air duct 3. Therefore, the airflow discharged from the outer air duct 3 is the key to ensuring the performance of the low-noise hair dryer, and the airflow discharged from the inner air duct 2 mainly plays the role of noise reduction and increasing the air output. In the utility model, the inner diameter of the air inlet 21 of the inner air duct 2 is smaller than the inner diameter of the air outlet 22. By reducing the inner diameter of the air inlet 21, the air flow rate entering the inner air duct 2 through the air inlet 21 is reduced to a certain extent. However, at the connection point between the inner air duct 2 and the outer air duct 3 and the air inlet end of the head 1, there are two channels for the airflow. The airflow lacks guidance when entering the inner air duct 2 or the outer air duct 3. On the one hand, it will cause airflow turbulence and aggravate noise. On the other hand, the inner air duct 2 may occupy too much airflow, resulting in insufficient airflow in the outer air duct 3, which may affect the performance of the hair dryer. Therefore, in one embodiment, the low-noise hair dryer further includes an air guide column 4 disposed at the air inlet end of the head 1, the air guide column 4 extending along the flow direction of the air flow in the air duct and shielding the air inlet 21 of the inner air duct 2, so that most of the air flow is blocked by the outer wall of the air guide column 4 and enters the outer air duct 3. It can be understood that the air guide column 4 only shields the air inlet 21 along the flow direction of the air flow in the air duct, rather than directly contacting and covering the air inlet 21, and part of the air flow can still enter the inner air duct 2 through the gap between the air guide column 4 and the air inlet 21; and this embodiment In the embodiment, since the air guide column 4 occupies the space at the air inlet end of the head 1 corresponding to the air inlet 21 of the inner air duct 2, most of the airflow at the air inlet end of the head 1 can only flow around the air guide column 4, that is, the air guide column 4 guides the airflow, so that most of the airflow is mainly located outside the air guide column 4, corresponding to the outer air duct 3, so that most of the airflow enters the outer air duct 3, ensuring the airflow flow in the outer air duct 3, thereby ensuring the performance of the hair dryer, and most of the airflow enters the outer air duct 3 under the guidance of the air guide column 4, which can reduce airflow turbulence to reduce noise. In this embodiment, the air guide column 4 is spaced apart from the inner air duct 2, and a small amount of airflow enters the inner air duct 2 through the gap between the air guide column 4 and the air inlet 21 of the inner air duct 2. The airflow needs to bend multiple times, and the airflow turbulence aggravates the noise. Therefore, an improved embodiment is obtained on the basis of the present embodiment. Figure 3It is shown that the air guide column 4 at least partially extends into the air inlet 21 of the inner air duct 2, and the air guide column 4 is spaced from the inner edge of the air inlet 21, so that part of the airflow enters the inner air duct 2 along the outer wall of the air guide column 4, and the outer wall of the air guide column 4 guides part of the airflow, thereby reducing the turbulence caused by multiple bending of the airflow, thereby further reducing the noise; in the embodiment of the present improvement, the outer diameter of the air guide column 4 gradually decreases along the flow direction of the airflow in the air duct, so that it can not only block the air inlet 21, but also allow the part with a smaller outer diameter to extend into the air inlet 21; based on the embodiment of the present improvement, further improvements are made, the outer wall of the air guide column 4 is in an outwardly convex arc shape along the flow direction of the airflow in the air duct, so that the airflow in the inner air duct 2 along the outer wall of the air guide column 4 has a certain wall attachment effect with the outer wall of the air guide column 4, thereby improving the guiding effect, and the outer periphery of the air guide column 4 is circular, thereby improving the smoothness of guiding the airflow entering the outer air duct 3 and reducing noise.
[0034] In one embodiment of the utility model, the heating element 5 in the head 1 is arranged in the outer air duct 3, and mainly heats the airflow in the outer air duct 3. Since the airflow in the outer air duct 3 mainly plays a drying role, the utilization rate of heat can be improved. In addition, the airflow entering the inner air duct 2 is not fully heated, so the temperature of the airflow discharged from the inner air duct 2 is relatively low. After the air outlet section outside the head 1 merges with the airflow with a higher temperature discharged from the outer air duct 3, the temperature of the air outlet section can be reduced to a certain extent. For a hair dryer, considering the user's body feeling, the temperature of the air outlet section cannot be too high. However, for the hair drying efficiency, the more heat carried in the airflow, the better. Therefore, the airflow in the inner air duct 2 has a neutralizing effect on the temperature of the air outlet section, so that the airflow discharged from the outer air duct 3 has room to further increase the temperature, thereby increasing the heating power of the heating element 5, so that the airflow per unit flow in the outer air duct 3 carries more heat, so that when the total temperature of the air outlet section remains unchanged, more heat is output, thereby improving the hair drying efficiency.
[0035] In a preferred embodiment of the utility model described above, the expansion section is a conical air duct, the inner conical surface faces the air outlet 22, and the inner air duct 2 is a flow expansion section from the air inlet 21 to the air outlet 22. Based on an improved implementation method obtained from this embodiment, the inner cavity of the head 1 is straight cylindrical along the flow direction of the airflow in the air duct, and a conical cylinder structure is arranged in the head 1 to form an inner air duct 2 in the conical cylinder structure, and an outer air duct 3 is formed between the conical cylinder structure and the inner wall of the head 1, so that not only the airflow in the inner air duct 2 is evenly guided and diffused, but also the inner diameter of the outer air duct 3 is gradually reduced along the flow direction of the airflow in the air duct, thereby realizing the acceleration of the airflow in the external air duct 3.
[0036] Figure 4 It is shown that in one embodiment of the utility model, the low-noise hair dryer also includes a handle 6 connected to the head 1, and the air inlet of the low-noise hair dryer can be arranged on the head 1 or on the handle 6, and the air inlet is connected to the air inlet end of the head 1.
[0037] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed in the present application, and these modifications or replacements should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.
Claims
1. A low-noise hair dryer, comprising a head with an air outlet and an air duct arranged in the head, the air duct comprising an inner air duct and an outer air duct sleeved on the periphery of the inner air duct, the inner air duct and the outer air duct are both connected to the air inlet end of the head, the outer air duct is connected to the air outlet, the inner air duct has an air inlet and an air outlet with an inner diameter larger than the air inlet, characterized in that: The inner diameter of at least part of the inner air duct increases from the air inlet end to the air outlet end, forming a flow expansion section to guide the air flow to diffuse toward the air outlet.
2. A low noise hair dryer according to claim 1, characterized in that: The minimum inner diameter of the air inlet end of the expansion section is consistent with the inner diameter of the air inlet, and the maximum inner diameter of the air outlet end is consistent with the inner diameter of the air outlet, so that the expansion section guides the air flow to diffuse and cover the air outlet.
3. A low noise hair dryer according to claim 2, characterized in that: The outlet end of the expansion section extends to the outlet or is connected to the outlet by a straight section whose inner diameter is consistent with the inner diameter of the outlet, and / or the inlet end of the expansion section extends to the inlet or is connected to the inlet by a straight section whose inner diameter is consistent with the inner diameter of the inlet.
4. A low noise hair dryer according to claim 1, characterized in that: The flow expansion section includes more than two small flow expansion sections, and the more than two small flow expansion sections are arranged continuously, at intervals, or staggered along the flow direction of the airflow in the inner air duct.
5. A low noise hair dryer according to claim 1, characterized in that: The inner air duct is a flow expansion section from the air inlet to the air outlet, so that the airflow is always guided and diffused by the flow expansion section from the air inlet to the air outlet.
6. A low noise hair dryer according to claim 1, characterized in that: The air inlet and the air outlet are coaxially arranged along the flow direction of the airflow in the inner air duct, so that the inner diameter of the expansion section increases in all directions to guide the airflow to diffuse in all directions.
7. A low noise hair dryer according to claim 1, characterized in that: The inner diameter of the expansion section gradually increases from the air inlet end to the air outlet end.
8. A low noise hair dryer according to claim 7, characterized in that: The expansion section is a conical air duct, and the inner conical surface faces the air outlet.
9. A low noise hair dryer according to claim 1, characterized in that: It also includes an air guide column arranged at the air inlet end of the head, which extends along the flow direction of the air flow in the air duct and blocks the air inlet of the inner air duct, so that most of the air flow is blocked by the outer wall of the air guide column and enters the outer air duct.
10. A low noise hair dryer according to claim 9, characterized in that: The air guide column at least partially extends into the air inlet of the inner air duct, and the air guide column is spaced apart from the inner edge of the air inlet, so that part of the air flow enters the inner air duct along the outer wall of the air guide column.