High-speed, low-noise, pressure-boosting air duct structure

Abstract

To provide a high-speed, low-noise, pressure-boosting air duct structure that can effectively rectify airflow, reduce the generation of turbulence, and reduce wind resistance and energy loss, thereby effectively improving the blowing wind speed and blowing distance and reducing operating noise. [Solution] The high-speed, low-noise, pressure-boosting air duct structure includes a motor frame with an accommodation cavity, an air duct housing, a fan, multiple blades (40), and a wind net. An air duct is provided within the air duct housing. The fan includes a motor (31) and a rotating drum (32). The wind net includes a fixed drum (51) and multiple guide vanes. The ends of the multiple guide vanes near the second end evenly surround the fixed drum diagonally, and each guide vane is bent into an arcuate shape along the axial direction of the fixed drum from the side near the second end to the side near the first end. By bending each guide vane into an arcuate shape along the axial direction of the fixed drum, an arcuate wind guide structure is formed.

Description

[Technical Field]

[0001] The present invention relates to the technical field of fans, and more particularly to a high-speed, low-noise, pressure-increasing air duct structure. [Background technology]

[0002] Current designs for micro air duct systems, such as portable seat fans and handheld fans, increasingly use high-speed motors (e.g., 13,000 rpm), but the resulting noise and airflow efficiency issues are becoming increasingly prominent. Conventional air duct structures typically employ silencer structures or silicone seals to reduce noise, which not only increase the system's volume and weight but also increase assembly complexity. Especially in applications requiring miniaturization and weight reduction, these additional structures often fail to meet actual needs. Furthermore, typical oblique wind net designs primarily use linear guide vanes, which are unable to guide or control the airflow direction, resulting in high turbulence intensity, significant energy loss, unstable wind speeds, and high noise (typically ≥ 65 dB when operating at 13,000 rpm).

[0003] In view of the above, there is a need to provide a high-speed, low-noise, pressure-boosting air duct structure to overcome the above deficiencies. Summary of the Invention [Problem to be solved by the invention]

[0004] The purpose of this invention is to provide a high-speed, low-noise, pressure-boosting air duct structure that improves the problems of existing micro air ducts, such as unstable wind speed and high noise, and aims to significantly reduce system noise and improve outlet wind speed and airflow uniformity. [Means for solving the problem]

[0005] In order to achieve the above object, the present invention a motor frame having an accommodation cavity, wherein positions on the motor frame that form openings on both sides of the accommodation cavity are defined as a first end and a second end, respectively; an air duct housing having an air duct provided therein, one end of which is fixed to the second end to connect the air duct to the accommodating cavity, and the other end of which serves as an outlet; a wind net including a fixed drum provided near the second end of the motor frame and a plurality of guide vanes connected between the fixed drum and an inner wall of the accommodating cavity, wherein ends of the plurality of guide vanes near the second end evenly surround the fixed drum in a diagonal direction, and each of the guide vanes is bent into an arc surface along the axial direction of the fixed drum from a side near the second end to a side near the first end; a fan provided in the accommodating cavity, the fan including a motor and a rotary drum, the motor being provided in the fixed drum and driving the rotary drum to rotate; and a plurality of vanes uniformly fixed to the outer surface of the rotary drum.

[0006] In one preferred embodiment, an end of the guide vane near the second end is radially offset with respect to the stationary drum and does not pass through the center of a cross section of the stationary drum.

[0007] In one preferred embodiment, the blade has at least one sawtooth on an edge thereof closer to the second end.

[0008] In one preferred embodiment, the number of the guide vanes is five to nine.

[0009] In one preferred embodiment, the number of the blades is 7 to 11.

[0010] In one preferred embodiment, the cross-sectional area of ​​the air duct decreases with increasing distance from the motor frame, and the diameter ratio of the end of the air duct closer to the motor frame to the end farther from the motor frame is 1:0.70 to 1:0.80.

[0011] In one preferred embodiment, an air duct nozzle extending into the air duct is provided on the side of the stationary drum closer to the air duct housing.

[0012] In one preferred embodiment, a first bearing and a second bearing are provided within the fixed drum and spaced apart in the axial direction, a drive shaft is provided within the rotating drum, and the drive shaft is inserted into and fixed to the first bearing and the second bearing, the motor includes a coil rotor and a magnet stator, the coil rotor is fixed to the drive shaft, and the magnet stator is fixed to the inner wall of the fixed drum.

[0013] In one preferred embodiment, the motor frame has a rounded chamfer on the side located at the first end.

[0014] In one preferred embodiment, the air duct housing further includes a wind direction adjustment ring, wherein the inner wall of the end of the air duct housing remote from the motor frame is provided with an annular groove that is recessed inward and partially spherical, the outer surface of the wind direction adjustment ring is protruding outward to fit into the annular groove, and rotation shafts are provided on both sides opposite the wind direction adjustment ring, and the end of the air duct housing remote from the motor frame is provided with rotation grooves that fit the rotation shafts, and the rotation shafts are inserted into the rotation grooves so that the wind direction adjustment ring can rotate within the annular groove around the straight line on which the two rotation shafts exist. [Effects of the Invention]

[0015] The high-speed, low-noise, boosted air duct structure provided by this invention has each guide vane bent into an arcuate surface along the axial direction of the fixed drum, forming an arcuate air guide structure, which effectively straightens the airflow, reduces turbulence, and reduces wind resistance and energy loss, thereby effectively improving the blowing air intensity and blowing distance and reducing operating noise. [Brief explanation of the drawings]

[0016] In order to more clearly explain the technical solutions of the embodiments of the present invention, the following will briefly describe the drawings necessary for the embodiments. It should be understood that the following drawings only illustrate some embodiments of the present invention and should not be considered as limiting the scope thereof. Those skilled in the art can obtain other related drawings based on these drawings without any creative efforts. [Figure 1] 1 is a perspective view of the high-speed, low-noise, pressure-boosting air duct structure provided by the present invention; [Figure 2] FIG. 2 is an exploded perspective view of the high-speed, low-noise, pressure-increasing air duct structure shown in FIG. [Figure 3] FIG. 2 is a vertical cross-sectional view of the high-speed, low-noise, pressure-boosting air duct structure shown in FIG. [Figure 4] FIG. 4 is a vertical cross-sectional view of the high-speed, low-noise, pressure-increasing air duct structure shown in FIG. 3, with part of the structure hidden, taken at a different angle. [Figure 5] FIG. 2 is a top view of the windscreen of the high-speed, low-noise, pressure-increasing air duct structure shown in FIG. 1. [Figure 6] 6 is a view of the wind net shown in FIG. 5 in the motor frame as viewed from the arrow AA. [Figure 7] FIG. 2 is a perspective view of the rotating drum and blades of the high-speed, low-noise, pressure-boosting air duct structure shown in FIG. 1. DETAILED DESCRIPTION OF THE INVENTION

[0017] In order to make the objectives, technical solutions and beneficial technical effects of the present invention more clearly understood, the present invention will be described in more detail below with reference to the drawings and specific embodiments. It should be understood that the specific embodiments described herein are for the purpose of illustrating the invention, but are not for the purpose of limiting the invention.

[0018] It should also be understood that the terminology used in the specification of the present invention is for the purpose of describing particular embodiments only, and is not intended to limit the present invention. As used in the specification of the present invention and the claims, the singular forms "a," "one," and "the" are intended to include the plural forms unless the context clearly dictates otherwise.

[0019] It should be further understood that the term "and / or," as used in the specification and appended claims, means and includes any and all possible combinations of one or more of the associated listed items.

[0020] In an embodiment of the present invention, a high-speed, low-noise, pressure-boosting air duct structure 100 is provided, which can be applied to micro air duct systems such as portable seat fans and handheld fans, and has the advantages of high rotation speed, long blowing distance, and low operating noise.

[0021] As shown in FIGS. 1 to 7, the high-speed, low-noise, pressure-increasing air duct structure 100 includes a motor frame 10 having an accommodating cavity 101, an air duct housing 20, a fan 30, a plurality of blades 40, and a wind net 50.

[0022] The motor frame 10 is generally cylindrical. The accommodating cavity 101 is coaxially formed inside the motor frame 10 and has a cylindrical shape. Both axial ends of the accommodating cavity 101 penetrate the motor frame 10, forming two openings. To facilitate the description of the positions of each component, the positions on the motor frame 10 that form the openings on both sides of the accommodating cavity 101 are defined as a first end 11 and a second end 12, respectively. The first end 11 is the location of the air inlet. Furthermore, the side of the motor frame 10 located at the first end 11 is chamfered to form a bell-mouth structure 102, which effectively increases the airflow, improving the airflow rate by approximately 1.2 times compared to a structure without the chamfer. It also effectively pre-compresses the airflow and reduces turbulence. Meanwhile, because the diameter of the accommodating cavity 101 remains unchanged, it stabilizes the laminar flow and reduces speed fluctuations.

[0023] An air duct 201 is provided within the air duct housing 20. The air duct 201 is generally conical in shape with a truncated top. One end of the air duct housing 20 is fixed to the second end 12, connecting the air duct 201 to the accommodation cavity 101, and the other end is an air outlet 202. The overall flow direction of the airflow is from the external environment to the first end 11 of the motor frame 10, the second end 12, the air duct 201, the air outlet 202, and back to the external environment.

[0024] Furthermore, the cross-sectional area of ​​the air duct 201 decreases with increasing distance from the motor frame 10, forming a tapered air duct. The diameter ratio of the end of the air duct 201 closest to the motor frame 10 to the end farther from the motor frame 10 is 1:0.70 to 1:0.80, preferably 1:0.75. This tapered air duct accelerates the discharged air to approximately 8 m / s, suppresses airflow separation, and extends the discharge distance. Combined with the bell-mouth structure 102 at the first end 11 of the motor frame 10, this creates a two-stage tapered structure for the entire motor frame 10 and air duct housing 20, synergistically reducing turbulence and lowering measured noise to 53.8 dB (less than the industry average of 60 dB).

[0025] The wind net 50 includes a fixed drum 51 disposed near the second end 12 of the motor frame 10, and a plurality of guide vanes 52 connected between the fixed drum 51 and the inner wall of the receiving cavity 101. The number of guide vanes 52 is 5 to 9, preferably 7. The ends of the guide vanes 52 near the second end 12 evenly surround the fixed drum 51 diagonally. The ends of the guide vanes 52 near the second end 12 are radially offset from the fixed drum 51 and do not pass through the center of the cross section of the fixed drum 51. Each guide vane 52 is bent in an arc shape along the axial direction of the fixed drum 51 from the side near the second end 12 to the side near the first end 11. The bending direction is opposite to the rotation direction of the blades 40, i.e., the arc shape is disposed toward one side of the blades 40, thereby reducing turbulent energy loss, increasing the blowing speed, and reducing operating noise.

[0026] In one embodiment, an air duct nozzle 60 is provided on the side of the fixed drum 51 closest to the air duct housing 20, extending into the air duct 201. The air duct nozzle 60 is generally conical in shape and can redirect the radial airflow to flow axially, avoiding excessive wind resistance, ensuring efficient airflow discharge, and directing the airflow along a predetermined path, thereby avoiding energy loss due to airflow collisions and turbulence within the air duct 201.

[0027] The fan 30 is disposed within the housing cavity 101 and includes a motor 31 and a rotating drum 32. The rotating drum 32 is attached to the side of the motor frame 10 away from the air duct housing 20, which can improve the balance stability of the motor 31, reduce vibration, and reduce current and noise.

[0028] Here, motor 31 is provided inside fixed drum 51 and rotates rotating drum 32. Specifically, first bearing 53 and second bearing 54 are provided inside fixed drum 51 and spaced apart in the axial direction. Drive shaft 33 is provided inside rotating drum 32 and is inserted into and fixed to first bearing 53 and second bearing 54. Motor 31 includes coil rotor 311 and magnet stator 312, with coil rotor 311 fixed to drive shaft 33 and magnet stator 312 fixed to the inner wall of fixed drum 51. Therefore, when coil rotor 311 is energized and rotates, drive shaft 33 is rotated about its own central axis, and further, rotating drum 32 is rotated relative to drive shaft 33.

[0029] As shown in FIG. 7, multiple blades 40 are fixed evenly to the outer surface of the rotating drum 32. The number of blades 40 is 7 to 11, preferably 9. At least one sawtooth 401 is provided on the edge of each blade 40 closer to the second end 12. Typically, the multiple sawtooth 401 are belt-like, which can reduce air noise and vibration when the blade 40 rotates at high speed, and extend the life of the blade 40. Here, the projections of two adjacent blades 40 in the axial direction of the rotating drum 32 do not partially overlap.

[0030] In one embodiment, as shown in FIG. 2 , the high-speed, low-noise, pressure-boosting air duct structure 100 further includes a wind direction adjustment ring 70. The inner wall of the air duct housing 20 at the end remote from the motor frame 10 is provided with an inwardly recessed, partially spherical annular groove 203. The outer surface of the wind direction adjustment ring 70 is convex outward to fit into the annular groove 203, so that the wind direction adjustment ring 70 cannot slip out of the annular groove 203 along both axial ends. Rotation shafts 71 are provided on both sides opposite the wind direction adjustment ring 70, and rotation grooves 204 that fit the rotation shafts 71 are opened at the end of the air duct housing 20 remote from the motor frame 10. The rotation shafts 71 are inserted into the rotation grooves 204 so that the wind direction adjustment ring 70 can rotate within the annular groove 203 around the line on which the two rotation shafts 71 exist, thereby changing the direction in which the air duct 201 blows outward within a certain range.

[0031] Furthermore, because the principles of fluid dynamics are not yet fully understood, the above-described structure, which was achieved through a fortuitous inspiration and continuous improvement efforts, cannot be accurately explained by detailed mathematical modeling as to why it has the above-described advantages and functions. However, CFD verification and actual sample testing can provide more reliable verification. Below, we will explain the significant advances and substantial features of the improved structure of the present invention compared to the prior art using an illustrative example including specific parameters. Example 1

[0032] (1) Two-stage tapered air duct structure: The diameter of the bell-mouth structure 102 at the first end 11 of the motor frame 10 gradually changes from 36.6 mm to 33.6 mm, thereby pre-compressing the airflow and reducing turbulence intensity. The accommodation cavity 101 in the motor frame 10 is cylindrical, with a diameter maintained at 33.6 mm to stabilize the laminar flow and reduce velocity fluctuations. The diameter of the air duct 201 in the air duct housing 20 gradually changes from 33.6 mm to 27.0 mm to speed up the discharge and suppress airflow separation.

[0033] (2) The motor 31 is a brushless motor, and its parameters are: operating voltage DC4V / 1.6A, diameter 15.6mm / height 40mm, copper-based heat dissipation housing, PWM speed control (20,500 rpm ±2%), maximum rotation diameter of the blades 40: 33mm, and a total of 9 blades.

[0034] (3) The wind net 50 is provided with seven guide vanes 52 each having an arcuate surface bent in the axial direction.

[0035] The fan manufactured in Example 1 was subjected to various tests under a bare motor, and the test results are shown in Table 1 below.

[0036] [Table 1]

[0037] As can be seen from the table above, compared to the existing design, the improved design of the present invention has a faster air velocity at the same blowing distance, i.e., a longer blowing distance, a lower rotation speed, less power consumption, and less noise for the same motor operating parameters. Here, at a voltage of 4V, the power can be controlled to about 6.5W and the rotation speed can be controlled to over 20,000 rpm.

[0038] As described above, the high-speed, low-noise, pressure-boosting air duct structure 100 provided by the present invention has each guide vane 52 bent into an arcuate surface along the axial direction of the fixed drum 51, thereby forming an arcuate air guide structure, which effectively straightens the airflow, reduces turbulence, and reduces wind resistance and energy loss, thereby effectively improving the blowing air intensity and blowing distance and reducing operating noise.

[0039] The present invention is not limited to the details described in the specification and embodiments, and further advantages and modifications will readily occur to those skilled in the art. Accordingly, without departing from the spirit and scope of the general concept as defined by the appended claims and their equivalents, the present invention is not limited to the specific details, representative apparatus, and illustrative examples shown and described herein. [Explanation of symbols]

[0040] 100 High-speed, low-noise, pressure-boosting air duct structure 10 Motor Frame 101 Storage Cavity 102 Bellmouth structure 11 1st end 12 2nd end 20 Air duct housing 201 Air Duct 202 Air Outlet 203 Annular groove 204 Rotating groove 30 fans 31 Motor 311 Coil rotor 312 Magnet stator 32 Rotating Drum 33 Drive shaft 40 Feathers 401 Sawtooth 50 Windbreaker Net 51 Fixed drum 52 Guide vane 53 First bearing 54 Second bearing 60 Air Duct Nozzle 70 Wind direction adjustment ring 71 Rotation axis

Claims

1. A high-speed, low-noise, pressure-increasing air duct structure, a motor frame having an accommodation cavity, wherein positions on the motor frame that form openings on both sides of the accommodation cavity are defined as a first end and a second end, respectively; an air duct housing having an air duct provided therein, one end of which is fixed to the second end to connect the air duct to the accommodating cavity, and the other end of which serves as an outlet; a wind net including a fixed drum provided near the second end of the motor frame and a plurality of guide vanes connected between the fixed drum and an inner wall of the accommodating cavity, wherein ends of the plurality of guide vanes near the second end evenly surround the fixed drum in a diagonal direction, and each of the guide vanes is bent into an arc surface along the axial direction of the fixed drum from a side near the second end to a side near the first end; a fan provided in the accommodating cavity, the fan including a motor and a rotary drum, the motor being provided in the fixed drum and driving the rotary drum to rotate; and a plurality of vanes fixed evenly to the outer surface of the rotating drum.

2. 2. The high-speed, low-noise, pressure-increasing air duct structure according to claim 1, wherein an end portion of the guide vane near the second end is radially offset from the fixed drum and does not pass through a center of a cross section of the fixed drum.

3. 2. The high-speed, low-noise, pressure-increasing air duct structure according to claim 1, wherein at least one sawtooth is provided on an edge portion of the vane that is closer to the second end.

4. 2. The high-speed, low-noise, pressure-increasing air duct structure according to claim 1, wherein the number of the guide vanes is 5 to 9.

5. 2. The high-speed, low-noise, pressure-increasing air duct structure according to claim 1, wherein the number of the blades is 7 to 11.

6. 6. The high-speed, low-noise, pressure-boosting air duct structure according to claim 5, wherein the cross-sectional area of ​​the air duct decreases with increasing distance from the motor frame, and the diameter ratio of the end of the air duct close to the motor frame to the end remote from the motor frame is 1:0.70 to 1:0.

80.

7. 2. The high-speed, low-noise, pressure-boosting air duct structure according to claim 1, wherein an air duct nozzle extending into the air duct is provided on the side of the fixed drum closer to the air duct housing.

8. 2. The high-speed, low-noise, pressure-boosting air duct structure according to claim 1, wherein a first bearing and a second bearing are provided within the fixed drum and spaced apart in the axial direction, a drive shaft is provided within the rotating drum, the drive shaft being inserted into and fixed within the first bearing and the second bearing, the motor including a coil rotor and a magnet stator, the coil rotor being fixed to the drive shaft, and the magnet stator being fixed to an inner wall of the fixed drum.

9. 2. The high-speed, low-noise, pressure-increasing air duct structure according to claim 1, wherein a rounded chamfer is formed on the side of the motor frame located at the first end.

10. 2. The high-speed, low-noise, pressure-boosting air duct structure according to claim 1, further comprising an airflow direction adjustment ring, wherein an inner wall of the air duct housing at an end remote from the motor frame is provided with an annular groove that is recessed inward and partially spherical, an outer surface of the airflow direction adjustment ring is convex outward to fit into the annular groove, and rotation shafts are provided on both sides opposite the airflow direction adjustment ring, and a rotation groove that fits the rotation shaft is opened at the end of the air duct housing remote from the motor frame, and the rotation shaft is inserted into the rotation groove so that the airflow direction adjustment ring can rotate within the annular groove around a straight line on which the two rotation shafts exist.

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