A noise reduction fan mesh cover

Abstract

The present invention relates to a noise reduction fan mesh cover, comprising an outer support ring, support strips, and an inner support ring, wherein the support strips are arranged on the outer support ring and the inner support ring to form a mesh cover, wherein the support strips are provided with a noise reduction mechanism, wherein the noise reduction mechanism comprises a plurality of first hollow tubes, wherein one end of the adjacent first hollow tubes is interconnected through a second hollow tube to form a branch pipe silencer structure, wherein the other end of the first hollow tube is provided with a cutout, and the length of the first hollow tube is not completely the same, so that after the original noise enters the first hollow tube, due to the different propagation distances of the inner and outer sounds, the phase changes, and the original noise is interfered with at the outlet, thereby achieving a noise reduction effect. The present invention can not only ensure the safety protection function of the mesh cover by introducing a branch pipe silencer structure, but also effectively reduce the fluid noise generated by the high-speed rotation of the fan blades, and has a simple structure and does not require redundant operations.

Description

Technical Field

[0001] The invention relates to the technical field of noise control, and in particular to a noise-reducing fan grille for controlling the noise of a fan grille. Background Art

[0002] At present, the main function of household fan guards is safety precautions. First, they cover the fan blades to prevent people from touching the high-speed rotating fan blades and causing safety accidents; second, they prevent the high-speed rotating fan blades from falling off and causing harm to people around. There is no further development and utilization of its functions.

[0003] At present, the noise reduction method used by fans sold on the market is mainly to use high-efficiency motors to make them run more smoothly and thus reduce noise. This noise reduction method is not only costly, but also has no direct noise reduction effect on the fluid noise generated by the high-speed rotation of the fan blades. Summary of the invention

[0004] In view of the shortcomings of the prior art, the present invention aims to provide a noise-reducing fan guard. By introducing a branch pipe silencer structure, not only can the safety protection function of the guard be ensured, but also the fluid noise generated by the high-speed rotation of the fan blades can be effectively reduced. The structure is simple and no unnecessary operations are required.

[0005] The present invention is achieved through the following technical solutions.

[0006] A noise reduction fan mesh cover, comprising an outer support ring, support strips, and an inner support ring, wherein the support strips are arranged on the outer support ring and the inner support ring to form a mesh cover, and a noise reduction mechanism is provided on the support strips. The noise reduction mechanism comprises a plurality of first hollow tubes, one end of adjacent first hollow tubes are interconnected through a second hollow tube to form a branch tube silencer structure, and a cutout is provided at the other end of the first hollow tube. The lengths of the first hollow tubes are not completely the same, so that after the original noise enters the first hollow tube, the phase changes due to the different propagation distances of the internal and external sounds, and interference is generated on the original noise at the intersection of the original noises, thereby achieving a noise reduction effect.

[0007] A plurality of first hollow tubes are connected to construct a plurality of branch tube silencer structures, so that the plurality of silencer structures have a superimposed effect.

[0008] Specifically, the second hollow tube is arc-shaped.

[0009] Preferably, one end of the plurality of first hollow tubes is arranged in a circular array and the other end is arranged in an elliptical array, so that one end of the first hollow tube is located on the circle and the other end is located on the ellipse, thereby making the lengths of the plurality of first hollow tubes not completely the same. The first hollow tubes are connected to form an ellipse to form a branch pipe silencer structure of different lengths, which can adapt to different noise environments.

[0010] Preferably, one end of the plurality of first hollow tubes is arranged in a spiral array, and the other end is arranged in an elliptical array, so that one end of the first hollow tube is located on the spiral, and the other end is located on the ellipse, and then the lengths of the plurality of first hollow tubes are not exactly the same. Branch pipe silencer structures of different lengths are formed to adapt to different noise environments.

[0011] Preferably, a notch for installing the noise reduction mechanism is provided in the middle of the support bar, so that the support bar is decomposed into an inner support bar located on the inner side and an outer support bar located on the outer side, and the two ends of the noise reduction mechanism are respectively connected to the inner support bar and the outer support bar.

[0012] Preferably, the inner support bars are arranged in an elliptical array, with the ends of the inner support bars located on the ellipse, and the outer support bars are arranged in a circular array, so that the lengths of the first hollow tubes are not exactly the same.

[0013] Specifically, a cross cavity is formed at the connection between the first hollow tube and the second hollow tube.

[0014] Specifically, the outer support ring is circular.

[0015] Specifically, the inner support ring is circular.

[0016] Specifically, the support bar is a solid support bar.

[0017] Preferably, the cutout (6) is located on the inner side of the mesh cover.

[0018] Compared with the prior art, the advantages of the present invention are: the noise-reducing fan mesh cover, by introducing a branch pipe silencer structure, can not only ensure the safety protection function of the mesh cover, but also effectively reduce the fluid noise generated by the high-speed rotation of the fan blades. The structure is simple and no unnecessary operation is required. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the main structure of the present invention;

[0020] Figure 2 yes Figure 1 Illustration of some branch pipe silencer structures;

[0021] Figure 3 It is a schematic diagram of the main structure of another embodiment of the present invention.

[0022] In the figure: 1, outer support ring, 2, support strip, 3, inner support ring, 4, first hollow tube, 5, second hollow tube, 6, incision, 7, cross cavity;

[0023] 201, outer support bar, 202, inner support bar. DETAILED DESCRIPTION

[0024] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but they are not intended to limit the present invention.

[0025] Example 1

[0026] like Figure 1 and Figure 2 As shown, a noise reduction fan mesh cover includes an outer support ring 1, support bars 2, and an inner support ring 3. The support bars 2 are arranged on the outer support ring 1 and the inner support ring 3 to form a mesh cover. The support bars 2 are provided with a noise reduction mechanism. The noise reduction mechanism includes a plurality of first hollow tubes 4. One ends of adjacent first hollow tubes 4 are interconnected through second hollow tubes 5 to form a branch tube silencer structure. The other ends of the first hollow tubes 4 are provided with cutouts 6. The lengths of the first hollow tubes 4 are not exactly the same, so that after the original noise enters the first hollow tube 4, the phase changes due to the different internal and external sound propagation distances, which interferes with the original noise at the outlet to achieve a noise reduction effect.

[0027] After the original noise enters the first hollow tube 4, it intersects with the original noise entering from the adjacent first hollow tube 4 at the connection point between the first hollow tube 4 and the second hollow tube 5. Since part of the original noise only passes through the first hollow tube 4 to reach the connection point, while the other part of the original noise passes through the adjacent first hollow tube 4 and the second hollow tube 5 connected thereto to reach the connection point, due to the different sound propagation distances, the phase changes, and interference occurs at the intersection of two different waves, thereby achieving a noise reduction effect; or, the original noise enters from a certain cutout 6, passes through the first hollow tube 4 plus the second hollow tube 5 connected thereto, plus the first hollow tube 4 connected to the second hollow tube 5 and adjacent to the first hollow tube 4 where the original noise enters, and intersects with another new original noise that follows at the cutout 6 where the original noise exits. Since part of the noise passes through the hollow tubes and part does not, the phases are different, and interference occurs at the intersection of two different waves, thereby achieving a noise reduction effect.

[0028] A plurality of first hollow tubes 4 are connected to construct a plurality of branch pipe silencer structures, so that the plurality of silencer structures have a superimposed effect.

[0029] As a specific implementation, the second hollow tube 5 is arc-shaped.

[0030] As a preferred embodiment, one end of several of the first hollow tubes 4 is arranged in a circular array, and the other end is arranged in an elliptical array, so that one end of the first hollow tube 4 is located on the circle, and the other end is located on the ellipse, thereby making the lengths of several of the first hollow tubes 4 not completely the same. In this embodiment, one end of the first hollow tube 4 located in the direction of the outer support ring 1 is located on the circle, and the end located in the inner support ring 3 is located on the ellipse. The first hollow tubes 4 are connected to form an ellipse to form branch pipe silencer structures of different lengths, which can adapt to different noise environments. Connecting multiple first hollow tubes 4 into an ellipse to construct branch pipe silencer structures of different lengths can increase the frequency range of noise reduction and improve the noise reduction effect. The noise reduction mechanism can be connected to the support bar 2 at both ends after the support bar 2 is broken, or it can be directly installed on the unbroken support bar 2; when the support bar 2 is broken, the support bar 2 is connected at both ends of the noise reduction mechanism, and its structure is the same as the structure described in the next paragraph.

[0031] As a preferred embodiment, a notch for installing the noise reduction mechanism is provided in the middle of the support bar 2, so that the support bar 2 is decomposed into an inner support bar 202 located on the inner side and an outer support bar 201 located on the outer side, and the two ends of the noise reduction mechanism are respectively connected to the inner support bar 202 and the outer support bar 201, and the inner support bar 202 is arranged in an elliptical array, and the end of the inner support bar 202 is located on the ellipse, and the outer support bar 201 is arranged in a circular array, so that the lengths of several of the first hollow tubes 4 are not exactly the same.

[0032] A cross cavity 7 is formed at the connection between the first hollow tube 4 and the second hollow tube 5 . The outer support ring 1 is circular, the inner support ring 3 is circular, and the support bar 2 is a solid support bar 2 .

[0033] The inlet of the branch pipe silencer structure is a cutout 6 which smoothly transitions from the horizontal support bar 2 to the first hollow pipe 4 during installation.

[0034] As a preferred embodiment, the cutout (6) is located inside the mesh cover.

[0035] Example 2

[0036] like Figure 3 As shown, the difference between Example 2 and Example 1 is that one end of the plurality of first hollow tubes 4 is arranged in a spiral array, and the other end is arranged in an elliptical array, so that one end of the first hollow tube 4 is located on the spiral, and the other end is located on the ellipse, and then the lengths of the plurality of first hollow tubes 4 are not completely the same. Branch pipe silencer structures of different lengths are formed to adapt to different noise environments.

[0037] The working principle of the branch pipe silencer structure is as follows:

[0038] When the mainstream fluid noise reaches the mesh, part of it will enter the first hollow tube 4 from the cutout 6. Due to the different sound propagation distances inside and outside the first hollow tube 4, the sound waves of a certain frequency have different phases. When the cross cavity 7 or the cutout 6 is combined, the sound waves with opposite phases cancel each other out, thereby achieving the effect of silencing. The silencing principle formula is as follows:

[0039]

[0040] Among them, f is the resonance frequency of the first hollow tube, n=1,2…, c0 is the speed of sound, Δl is the sound path difference of two waves interfering with each other at the cross cavity 7, one wave path is the length of a first hollow tube 4, and the other wave path is the sum of the lengths of the second hollow tube 5 connected thereto and another first hollow tube 4 connected to the second hollow tube 5, or Δl is the total length of a branch tube, or Δl is the difference between the total length of a branch tube and the distance between the two incisions 6 thereon. When the mainstream noise reaches this frequency, the maximum sound-absorbing effect can be achieved.

[0041] A plurality of first hollow tubes 4 are connected in parallel to construct a plurality of branch pipe silencer structures, so that the plurality of silencer structures have a superimposed effect.

[0042] Among them, the first hollow tube 4 and the second hollow tube 5 can have the same material and diameter, but different curvature; they can also have the same diameter but different materials and curvature; they can also have different diameters, materials and curvatures, but can ensure smooth transition of sound transmission.

[0043] By connecting a plurality of first hollow tubes 4 into an ellipse and constructing a branch tube silencer structure with different lengths, the frequency range of noise reduction can be increased and the noise reduction effect can be improved.

[0044] The above description is only a preferred embodiment of the present invention, and does not limit the implementation mode and protection scope of the present invention. For those skilled in the art, it should be aware that all solutions obtained by equivalent substitutions and obvious changes made using the description and illustrations of the present invention should be included in the protection scope of the present invention.

Claims

1. A noise reduction fan mesh cover, comprising an outer support ring (1), support strips (2), and an inner support ring (3), wherein the support strips (2) are arranged on the outer support ring (1) and the inner support ring (3) to form a mesh cover, characterized in that: The support bar (2) is provided with a noise reduction mechanism, the noise reduction mechanism comprising a plurality of first hollow tubes (4), one end of adjacent first hollow tubes (4) being interconnected via second hollow tubes (5) to form a branch tube noise reduction structure, the other end of the first hollow tubes (4) being provided with a cutout (6), the lengths of the first hollow tubes (4) being not completely the same, so that after the original noise enters the first hollow tube (4), due to the different propagation distances of the internal and external sounds, the phase changes, and interference is generated on the original noise at the intersection of the original noises, thereby achieving a noise reduction effect; The second hollow tube (5) is arc-shaped; A notch for installing the noise reduction mechanism is provided in the middle of the support bar (2), so that the support bar (2) is decomposed into an inner support bar (202) located on the inner side and an outer support bar (201) located on the outer side, and two ends of the noise reduction mechanism are respectively connected to the inner support bar (202) and the outer support bar (201).

2. The noise reduction fan guard according to claim 1, characterized in that: One end of the plurality of first hollow tubes (4) is arranged in a circular array, and the other end is arranged in an elliptical array, so that one end of the first hollow tube (4) is located on the circle, and the other end is located on the ellipse, thereby making the lengths of the plurality of first hollow tubes (4) not completely the same.

3. The noise reduction fan guard according to claim 1, characterized in that: One end of the plurality of first hollow tubes (4) is arranged in a spiral array, and the other end is arranged in an elliptical array, so that one end of the first hollow tube (4) is located on the spiral, and the other end is located on the ellipse, thereby making the lengths of the plurality of first hollow tubes (4) not completely the same.

4. The noise reduction fan guard according to claim 1, characterized in that: The inner support bars (202) are arranged in an elliptical array, with the ends of the inner support bars (202) located on the ellipse, and the outer support bars (201) are arranged in a circular array, so that the lengths of the plurality of first hollow tubes (4) are not exactly the same.

5. The noise reduction fan guard according to claim 1, characterized in that: A cross cavity (7) is formed at the connection between the first hollow tube (4) and the second hollow tube (5).

6. The noise reduction fan guard according to claim 1, characterized in that: The outer support ring (1) is circular.

7. The noise reduction fan guard according to claim 1, characterized in that: The inner support ring (3) is circular.

8. The noise reduction fan guard according to claim 1, characterized in that: The cutout (6) is located on the inner side of the mesh cover.

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