Neck-hung fan

Abstract

A neck-hanging fan is characterized by being provided with a first shell and an air blowing module. The first shell is made of a flexible material, the flexible material is cloth or a flexible rubber material, and the flexible rubber material is one or a combination of rubber, silica gel, TPE or TPU; an inner cavity of the first shell is of a hollow structure, and at least one air inlet and at least one air outlet are formed in the first shell; the first shell is made of a flexible material and can restrain and absorb broadband noise generated when the neck-hanging fan works.

Description

Technical Field

[0001] The invention relates to a design scheme of a neck hanging fan made of a flexible shell, and in particular to a scheme of propping up the shell by utilizing air pressure difference. Background Art

[0002] After the neck hanging fan was launched in 2020, it can free the hands of users to blow air to the head for heat dissipation, bringing users a sense of coolness and pleasure during cooking, running, traveling, and daily work, so its annual sales volume exceeds 10 million units. The structure of most products is basically the same as the utility model patent CN211059041U.

[0003] However, existing neck-hanging fans have the following three main problems that users generally complain about: the first is loud noise and irritation, because when the temperature exceeds 30℃, existing products will generally work in high-speed blowing mode, and the maximum continuous noise measured at the user's ear is 85~90dB@50Hz and 45~50dB@1.5kHz. Since high-volume low-frequency noise makes people feel sleepy, and the sound of 1~3kHz is the most sensitive to the human ear, the above noise will seriously affect the user's mood; the second is that the product weight is about 220~300g, and the area in contact with the skin is small. Many customers feel tired in the neck and their skin is oppressed and painful after wearing it; the third is that it is difficult to store and carry, because all current neck-hanging fans are made of U-shaped hard plastic, so the minimum size of the current neck-hanging fans is ≥15*20*6cm3, which cannot be put into the pocket of clothes, is difficult to put into a backpack, and will also take up a lot of space in a suitcase.

[0004] At the same time, there are three minor issues that have been complained about: the first minor issue is that the appearance is very homogeneous, which causes trouble for users who pursue individuality; the second minor issue is that the area where the user's skin contacts the existing neck hanging fan is prone to sweat accumulation and odor; the third minor issue is that the product cost is relatively high, which makes it difficult to promote in low-income countries and regions.

[0005] Therefore, the present invention proposes a neck hanging fan, which can simultaneously solve the above three major problems commonly complained by users and solve the other three minor problems. Summary of the invention

[0006] The present invention discloses a neck hanging fan, which is characterized in that it has a first shell and a blower module; the first shell is made of a flexible material, the flexible material is cloth or a thin-walled soft rubber material, and the soft rubber material is one or a combination of rubber, silicone, TPE or TPU; the inner cavity of the first shell is a hollow structure, and the first shell is provided with at least one air inlet and at least one air outlet; the blower module is arranged at the air inlet, the air intake of the blower module is connected to the outside air, and the air outlet of the blower module is connected to the inside of the first shell; the blower module has an electric fan and a control circuit module, and the control circuit module is used to control the start and stop of the electric fan; when the neck hanging fan is not working, the flexible material The first shell is in a deflated state, and when the neck hanging fan is working, outside air enters from the air inlet, and the formed airflow passes through the electric fan and then enters the first shell, and establishes air pressure in the inner cavity of the first shell, and the flexible material changes from a deflated state to an expanded state, and the airflow is blown out from the air outlet; in the expanded state, the shape of the first shell forms an open-loop annular structure or a closed-loop annular structure; the first shell absorbs the noise generated by the airflow through the dynamic deformation of the flexible material, and the first shell suppresses the vibration noise generated by the blower module through the low resonance frequency of the flexible material. The first shell has a thin-wall structure near the air outlet, and the corresponding cavity has a certain volume, so that the airflow at the air outlet is smooth and the noise at the air outlet is suppressed.

[0007] In order to facilitate the neck-hanging fan whose first shell is in the shape of an open-loop ring structure to be securely worn on the user's neck in the expanded state, especially when the user needs to use it while jogging, matching temporary locking modules are provided near the two end areas of the first shell, and the temporary locking modules are implemented by magnets, mechanical buckles, etc.; when the temporary locking module is locked, the first shell forms a closed-loop structure.

[0008] In order to improve the appearance when worn and reduce the entry of dust and hair, the air inlet of the neck-hanging fan disclosed in the present invention will face the user's body. In order to avoid the air inlet being blocked and thus making it impossible to inhale, at least one protruding structure is provided in the area of ​​the first shell close to the air inlet. When the neck-hanging fan is working, the protruding structure is used to press against the user's body to separate the air inlet from the user so that air can be inhaled.

[0009] In order to reduce the product quality and volume as much as possible, the first shell is made of a very thin material without its own support force. Therefore, when the neck hanging fan disclosed in the present invention is working, the air pressure inside the first shell is greater than the external air pressure. The first shell is supported by internal air to form a U-shape, a C-shape or an open ring with overlapping parts, and supports to form the convex structure. Preferably, when the neck hanging fan is working, the air inside the first shell supports to form the convex structure.

[0010] In order to reduce the vibration of the first shell due to the vibration of the air inside the first shell, thereby emitting noise to the outside world, a sound-absorbing layer is provided on the inner wall of the first shell. The material of the sound-absorbing layer is sound-absorbing and heat-generating fibers such as polyurethane fiber, rock wool fiber, or sheet-like artificial sponge material.

[0011] In the innovation and experimentation stage of the present invention, firstly, the inventor conducted a detailed study on the causes of the noise and found that there are two reasons: The first aspect is caused by the fan unit working. In order to control the volume, the existing hanging neck fan products use centrifugal fans with an impeller diameter of about 40mm. This centrifugal fan needs a speed of >2400rpm to provide the blowing volume and wind pressure required for high-speed blowing. At the same time, the number of blades on this impeller is about 20~30. Therefore, under the action of the airflow on the blade surface and the vortex separated from the blade surface, it will also generate low-volume high-frequency noise NH1 of 0.8~1.8kHz and discontinuous airflow AN of the same frequency; also because the current product uses hard plastic to make a diffuser volute type air duct near the impeller in order to control the volume and increase the wind pressure, the gas discharged from the impeller will immediately hit the inner wall of the air duct and then rebound to the impeller, so that the impeller, air and volute will produce broadband coupled vibration noise NW; the last point is that because each impeller has a center of gravity that deviates from the rotation axis, the impeller will produce eccentric vibration when it rotates, and then drive the product shell connected by rigid connection to produce vibration noise NL, and the volume of NL is proportional to the square of the rotation speed.

[0012] The second point is caused by the design defects of the air duct in the air outlet area. There are multiple air outlets on the two arms of the existing hanging neck fan products. In order to make each air outlet output the same wind, a gradually narrowing air duct is designed inside the two arms of the product and below the air outlet. When the discontinuous airflow AN flows in one direction from the air duct inlet and then turns about 90 degrees and flows out from the air outlet with a wall thickness of about 1 / 10 of the air outlet width, the discontinuous airflow AN will generate multiple 0.8~1.8kHz turbulence and mix together, thereby reducing the wind speed of the air outlet and generating the noise NH2 of the airflow hitting the product shell and the airflow hitting each other.

[0013] Therefore, the solution should be carried out in accordance with the above two aspects: First, we will think about and test the noise generated when the fan unit is working. Because the air volume = air outlet area x blade airflow velocity, under the premise that the required air volume remains unchanged, as long as a fan with a larger diameter impeller is used, the speed can be reduced. For example, by using a centrifugal fan with a diameter of 80mm, the same air volume as the existing 40mm diameter fan can be obtained at a speed of about 1200rpm and 1 / 2 of the existing blade airflow velocity, thereby obtaining a lower volume high-frequency noise NH1; and because the speed is reduced, the volume of the low-frequency noise HL will also be greatly reduced; at the same time, the inner wall of the product housing is kept as far away from the impeller as possible, and the existing volute is expanded or even eliminated, which can greatly reduce the generation of NW. After testing, when the distance between the inner wall of the product housing and the impeller is greater than the blade length, the coupling between the impeller, air and the product housing will be significantly reduced.

[0014] However, if an 80mm diameter fan is used to replace the existing 40mm diameter fan, and the blade length is about 10mm, then the neck hanging fan with patent authorization number CN211059041U structure will continue to be used, the volume will increase by about 2 times, the material cost will increase by 2 times, and the quality will increase by 2 times, which is not feasible at all.

[0015] Secondly, we considered and experimented with the noise caused by the design defects of the air duct in the air outlet area. Because the airflow with the lowest noise is laminar flow, the laminar flow has the highest wind speed when driving air at the same power, and the condition for obtaining laminar flow is stable airflow and a very short airflow duct. To obtain stable airflow, the airflow entering the air outlet needs to come from as many directions as possible in the shell of the hanging neck fan product, so the cavity in the product shell needs to be as large as possible and the current air duct needs to be removed; to make the airflow duct as short as possible, the product shell needs to be as thin as possible at the air outlet, and the slope from the shell near the air outlet to the air outlet should be as small as possible. In short, the thinner the product shell, the better. However, these two technical requirements are contradictory, because increasing the volume of the cavity in the product shell requires increasing the wall thickness of the product shell to ensure mechanical strength, while reducing the wall thickness of the product shell will lead to a significant reduction in mechanical strength.

[0016] In summary, it is impossible to achieve a low-noise neck-hanging fan by using the utility model patent CN211059041U structure, so a completely new idea and design solution is needed, which is why the idea of ​​using flexible material as the first shell came into being.

[0017] Through experiments, the inventors found that if a first shell with a U-shape, C-shape or an open ring with overlapping parts and a large internal cavity space after inflation is made of flexible material, and an air inlet is designed at the bottom of the U-shape, the leftmost part of the C-shape or the part opposite to the annular notch, and a fan with a diameter of 80mm and a thickness of 30mm is placed horizontally as the main part of the blower module, even if the 80mm diameter fan may work at 2400rpm to replace the two 40mm diameter fans in the existing neck hanging fan for blowing the same air volume, the fan and the first shell cannot form coupled vibration, so the NL is very low; and because most of the cavity in the first shell is away from the wind The vibration frequencies of the fan blades and the first shell are very low, and there is outside air outside the first shell that can serve as a buffer. Therefore, the coupled vibrations between the blades, the airflow and the first shell are also very weak, so NW is very low; also because the inner cavity of the first shell is very large, the discontinuous airflow AN generated by the fan blades can easily combine into a continuous airflow, and the vibration frequency of the first shell is very low, which is far from the frequency band of NH1. Therefore, it is basically difficult to be affected by the discontinuous airflow AN to generate NH2 noise; further, when the first shell contains a sound-absorbing layer made of sound-absorbing and heat-generating fibers such as polyurethane fibers, rock wool fibers, or sheet-like artificial sponge materials, the noise of NH1 will also be absorbed.

[0018] In addition, since the first shell is basically supported by the air in the cavity whose pressure is greater than the external air pressure, the outer wall of the first shell can be made very thin, and the air flowing out of the air outlet comes from all directions of the cavity, so the airflow flowing out of the air outlet is close to or is laminar flow, so the wind speed at the air outlet is the largest and the wind flow noise at the air outlet is the smallest.

[0019] In summary, the present invention uses flexible materials instead of hard materials to make the main shell of the neck hanging fan, which can effectively suppress various noises generated by the blower module and significantly reduce the turbulent noise at the air outlet. According to the actual prototype test, while providing the same cooling feeling as the existing neck hanging fan, the noise of the present invention is 50~55dB@50Hz and 30~35dB@2kHz, which is reduced by 35dB and 15dB respectively. The first common complaint problem has been solved.

[0020] At the same time, because the first shell of the neck-hanging fan made using the technology of the present invention is basically empty, a large number of existing hard plastic supporting structural parts of the neck-hanging fan can be saved, so the total mass is significantly reduced. According to the comparison of the actual prototypes, the mass of the neck-hanging fan made using the technology of the present invention can be reduced by about 50% compared with the existing neck-hanging fan, which is only about 110g. And because the first shell is flexible, it has a larger area in contact with the human body, so the pressure on the skin is significantly reduced, which is estimated to be reduced by more than 80%. Therefore, the neck-hanging fan made using the technology of the present invention is light in weight and low in pressure, and it is not easy for users to feel tired and painful. The second common complaint has been solved.

[0021] Preferably, when the first shell is made of cloth, because the surface of the cloth is covered with micropores, a small amount of air can also be released from the area close to the skin to help the skin in this area dissipate heat. This feature solves the small problem that the area close to the skin of the existing neck hanging fan is prone to sweat accumulation and odor.

[0022] Finally, when the neck hanging fan made by the technology of the present invention stops working, the first shell will deflate, and the user can easily fold it into a ball for storage. According to the actual test of the prototype, the minimum size of the present invention in the folded state is 8*8*5cm3, so it can be easily stuffed into the pocket of clothing. The third common complaint problem has been solved.

[0023] In actual production, since the first shell is made of very simple cloth sewing or soft plastic dipping process, there is no need to prepare complex plastic molds, so the production cost is significantly lower than the hard plastic materials and processes used in existing neck hanging fans. In addition, it is easy to achieve small batch customized production by sewing decorations or heat shrink film printing on the outer surface of the first shell, so the present invention is more suitable for the needs of the personalized market.

[0024] In summary, the neck-hanging fan disclosed by the present invention has the advantages of very low noise when in use, light weight and low pressure when hung around the neck, very small storage volume, low cost, skin-friendly and no sweat accumulation, and easy to achieve personalized customization. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is the state when the first embodiment of the present invention is not working.

[0026] Figure 2 This is the state when the first embodiment of the present invention is working.

[0027] Figure 3 It is the first cross-sectional view of the first embodiment of the present invention when it is working.

[0028] Figure 4 It is a second cross-sectional view of the first embodiment of the present invention when it is working.

[0029] Figure 5 Schematic diagram of a second embodiment of the present invention. DETAILED DESCRIPTION

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following is a brief introduction to the drawings required for the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention and do not limit the scope of application of the present invention. For ordinary technicians in the field, the present invention can be applied to other similar scenarios based on these drawings without creative work; as shown in this specification and claims, unless the context clearly indicates an exception, the words "one", "a", "a kind" and / or "the" do not specifically refer to the singular, but may also include the plural. In general, the terms "including" or "comprising" only indicate that the steps and elements that have been clearly identified are included, and these steps and elements do not constitute an exclusive list, and the method or device may also include other steps or elements. The term "based on" means "based at least in part". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one other embodiment".

[0031] In all the drawings of the specification, the dotted lines with arrows represent the direction of air flow.

[0032] Figure 1 and Figure 2 The first embodiment of the present invention is shown in two states: when not in operation and when in operation. When not in operation, the first housing 11 is deflated, while when in operation, the first housing 11 is bulged, and the convex structure 114 near the air inlet 111 is also bulged. In the first embodiment of the present invention, the first housing 11 is sewn with cloth.

[0033] When the first embodiment of the present invention is worn on the user's neck, the raised structure 114 presses against the user's body and raises or suspends the air inlet 111, so that the blowing module 12 can inhale air. Most of the inhaled air will pass through the air outlet 112 and blow toward the user, and a small amount of air will pass through the micropores on the surface of the first shell 11 and be blown out, including to the area that fits the user's body.

[0034] The first embodiment of the present invention is cut along the central axis of the air blowing module 12. Figure 3As shown, the blower module 12 includes a centrifugal fan 121, a secondary battery 122 for power supply, a control circuit module 123 for controlling the centrifugal fan 121 and charging and discharging the secondary battery 122, a dust cover 124 and a bracket 125; the bracket 125 and the dust cover 124 fix the blower module 12 at the air inlet 111 of the first shell 11, and the other parts of the blower module 12 are surrounded by the air chamber cavity 113 in the first shell 11, so that the centrifugal fan 121 can draw air from the outside of the first shell 11 through the air inlet 111 and send it into the air chamber cavity 113 to fill the air chamber cavity 113. There is a user controller 1231 on the control circuit module 123, and the user can operate the user controller 1231 by pressing, touching or remote control, and finally control the control circuit module 123 to start and stop the centrifugal fan 121 and adjust the speed of the centrifugal fan 121.

[0035] The first embodiment of the present invention is cut along the air outlet 112 (as shown in FIG. Figure 4 (Double-arrow dashed line view in the upper left corner) Figure 4 As shown, the air in the air chamber cavity 113, because the air pressure is higher than the outside air, will flow through the outer wall of the first shell 11 whose wall thickness is much smaller than the cross-sectional width of the air outlet 112 at the same pressure and speed from each direction on one side of the air outlet 112, thereby forming a stable laminar flow and blowing out in the direction away from the first shell 11.

[0036] In order to ensure that the first embodiment of the present invention can be worn more stably on the user's neck, Figure 5 As shown, a pair of magnets 115 are respectively arranged on the inner walls of the two ends of the first shell 11 to make a second embodiment. When worn on the neck, the two magnets 115 will fit each other due to the magnetic attraction after being close to each other, so that the first shell 11 is temporarily closed.

Claims

1. A neck hanging fan, characterized in that: It has a first shell and a blower module; The first shell is made of a flexible material, the flexible material is cloth or soft rubber material, and the soft rubber material is one or a combination of rubber, silicone, TPE or TPU; The inner cavity of the first shell is a hollow structure, and the first shell is provided with at least one air inlet and at least one air outlet; The air blowing module is arranged at the air inlet, the air inlet of the air blowing module is connected to the outside air, and the air outlet of the air blowing module is connected to the inside of the first shell; The blower module comprises an electric fan and a control circuit module, wherein the control circuit module is used to control the start and stop of the electric fan; When the neck hanging fan is not working, the flexible material is in a deflated state. When the neck hanging fan is working, outside air enters from the air inlet, the formed airflow passes through the electric fan and then enters the first shell, and air pressure is established in the inner cavity of the first shell, the flexible material changes from a deflated state to an expanded state, and the airflow is blown out from the air outlet; In the expanded state, the first shell is shaped into an open ring structure or a closed ring; The first shell absorbs the noise generated by the airflow through the dynamic deformation of the flexible material. The first shell suppresses the vibration noise generated by the blower module through the low resonance frequency of the flexible material. The first shell has a thin-wall structure near the air outlet, and the corresponding cavity has a certain volume, so that the airflow at the air outlet is stable and the noise at the air outlet is suppressed.

2. According to claim 1, the neck hanging fan is characterized in that: When the first shell shape forms an open-loop annular structure in the expanded state, the open-loop annular structure is U-shaped, C-shaped, or an open annular shape with overlapping parts.

3. The neck hanging fan according to claim 1, characterized in that: When the first shell is in an expanded state and forms an open-loop annular structure, a matching temporary locking module is provided near the two end regions of the first shell, and the temporary locking module is implemented by a magnet or a mechanical buckle; When the temporary locking module is locked, the first shell forms a closed loop structure.

4. The neck hanging fan according to claim 1, characterized in that: The first housing is provided with at least one protruding structure in an area close to the air inlet. When the neck hanging fan is working, the protruding structure is used to prevent the air inlet from being in close contact with the user's body surface.

5. A neck hanging fan according to claims 1 and 4, characterized in that: When the neck hanging fan is working, the air inside the first shell supports the convex structure.

6. The neck hanging fan according to claim 1, characterized in that: The inner wall of the first shell is provided with a sound-absorbing layer, and the material of the sound-absorbing layer is sound-absorbing and heat-generating fiber or sheet-like artificial sponge material.

7. The neck hanging fan according to claim 1, characterized in that: The sound-absorbing and heat-generating fibers are polyurethane fibers and rock wool fibers.

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