Noise reduction and reinforcement structure for pipe wall

Abstract

The invention relates to the technical field of air pipe noise reduction and reinforcement, and discloses a pipe wall noise reduction and reinforcement structure which comprises a supporting mechanism, the supporting mechanism comprises a first fixing frame, an elastic assembly is fixedly connected to the outer wall of the first fixing frame, and a second fixing frame is fixedly connected to the outer wall of the side, away from the elastic assembly, of the first fixing frame. A first sliding frame is arranged at the top of the second fixing frame, a screw rod is rotatably connected to the inner wall of the first sliding frame, a fixing shaft is fixedly connected to the outer wall of the second fixing frame, and when the fan runs, the rectangular air pipe is reinforced through the supporting mechanism, vibration generated by the fan is absorbed through an elastic assembly, and the vibration generated by the fan is reduced; and the sound insulation sponge is reinforced through the adjusting assembly, so that the sound insulation sponge is more attached to the outer wall of the rectangular air pipe, and the noise blocking effect of the sound insulation sponge is improved.

Description

Technical Field

[0001] The invention relates to the technical field of air duct noise reduction and reinforcement, and in particular to a pipe wall noise reduction and reinforcement structure. Background Art

[0002] Rectangular duct is a common ventilation duct, which is widely used in the ventilation system of buildings. In order to reduce the noise and vibration of rectangular duct during operation, it is usually necessary to perform noise reduction and reinforcement treatment on it.

[0003] A patent application with application number CN202323229330.1 discloses a ventilation duct support and hanger reinforcement system, including a pipe composed of multiple sections of rectangular air ducts, wherein a right-angle reinforcement rib is arranged in the middle position of the rectangular air duct; an insulation layer is arranged on the pipe, the horizontal part of the pipe is fixed by a horizontal bracket, and the vertical part is fixed by a vertical bracket, and steel plates and anti-corrosion pads are arranged between the pipe and the horizontal bracket and the vertical bracket.

[0004] To sum up, when the rectangular air duct is used in an environment with strict noise requirements, when the fan is running, if the rectangular air duct is not effectively vibration-isolated, the vibration generated by the fan will be directly transmitted to the air duct, causing the air duct to vibrate and make noise. In the traditional way, the method of adding sound insulation sponge to the outer wall of the rectangular air duct has the problems of cumbersome reinforcement operation and inconvenient replacement, and if the sound insulation sponge cannot fit completely with the outer wall of the rectangular air duct, its noise blocking effect will be significantly weakened.

[0005] To this end, we proposed a pipe wall noise reduction and reinforcement structure. Summary of the invention

[0006] In view of the deficiencies of the prior art, the present invention provides a pipe wall noise reduction and reinforcement structure to solve the problems raised in the above background technology.

[0007] To achieve the above-mentioned object, the present invention provides the following technical solutions: a pipe wall noise reduction and reinforcement structure, comprising a supporting mechanism, the supporting mechanism comprising a first fixing frame, the outer wall of the first fixing frame is fixedly connected to an elastic component, the outer wall of the first fixing frame away from the elastic component is fixedly connected to a second fixing frame, a first sliding frame is arranged on the top of the second fixing frame, a screw is rotatably connected to the inner wall of the first sliding frame, and a fixed shaft is fixedly connected to the outer wall of the second fixing frame, and further comprising: The adjusting assembly includes a second sliding frame slidably connected to the fixed shaft, a second connecting rod is provided on the inner wall of the second sliding frame, a second spring is fixedly connected to the outer wall of the second sliding frame on one side close to the second fixed frame, an end of the second spring away from the second sliding frame is fixedly connected to the second fixed frame, and the inner wall of the second sliding frame on one side close to the second fixed frame is rotatably connected to the first connecting rod via a rotating shaft.

[0008] According to the above technical solution, the outer wall of the first sliding frame is rotatably connected to the first rotating rod via a rotating shaft, the end of the first rotating rod away from the first sliding frame is rotatably connected to the second rotating rod via a rotating shaft, and the end of the second rotating rod away from the first rotating rod is rotatably connected to the second fixed frame, the number of the first rotating rods is two, and the two first rotating rods are symmetrically arranged with the central axis of the first sliding frame as the center, and the first sliding frame approaches one side of the second fixed frame under the action of the screw, so that the first sliding frame squeezes the second rotating rod at the same time through the first rotating rod.

[0009] According to the above technical solution, the inner wall of the second connecting rod on the side away from the second sliding frame is rotatably connected to the second fixed frame, a second through hole is opened on the inner wall of the second connecting rod, and a pressure plate is rotatably connected to the outer wall of the second connecting rod on the side away from the second fixed frame through a rotating shaft. The inner wall of the second through hole is slidably connected to the second sliding frame, and the pressure plate applies different forces to the sound insulation sponge according to the different distances between the second sliding frame and the second fixed frame.

[0010] According to the above technical solution, a third through hole is opened on the inner wall of the pressure plate close to the second fixed frame, and a connecting shaft is fixedly connected to the outer wall of the pressure plate close to the second fixed frame. There are two connecting shafts, and the two connecting shafts are symmetrically arranged with the central axis of the limit plate as the center.

[0011] According to the above technical solution, one end of the connecting shaft away from the pressure plate passes through the second connecting rod and is fixedly connected to a limiting plate. A third spring is fixedly connected to the outer wall of the limiting plate on one side close to the second connecting rod. One end of the third spring away from the limiting plate is fixedly connected to the second connecting rod. The third spring is used for resetting the pressure plate.

[0012] According to the above technical solution, one end of the fixed shaft away from the second fixed frame is fixedly connected to a fixed block, the inner wall of the fixed block is fixedly connected to an arc rod, the inner wall of the arc rod is provided with a first through hole, the inner wall of the first through hole is slidably connected to the second sliding frame, the number of the fixed shafts is two, and the two fixed shafts are symmetrically arranged with the central axis of the second fixed frame as the center.

[0013] According to the above technical solution, one end of the arc rod away from the fixed block is rotatably connected to a clamping rod through a rotating shaft, and the outer wall of the clamping rod close to the arc rod is fixedly connected to a first spring, and one end of the first spring away from the clamping rod is fixedly connected to the arc rod. The angle of the clamping rod is adjusted by the first spring, so that the sound insulation sponge on the outer wall of the connecting pipe can be fixed more conveniently.

[0014] A rectangular air duct comprises: a connecting pipe, the outer wall of the connecting pipe is fixedly connected to a first fixing frame, the outer wall of the connecting pipe is fixedly connected to a flange, one end of the flange away from the connecting pipe is fixedly connected to a sealing ring, and the inner wall of the connecting pipe is fixedly connected to a sound absorbing board.

[0015] Compared with the prior art, the present invention provides a pipe wall noise reduction and reinforcement structure, which has the following beneficial effects: 1. The present invention provides a pipe wall noise reduction and reinforcement structure. When the fan is running, the rectangular air duct is reinforced by a supporting mechanism, the vibration generated by the fan is absorbed by an elastic component, and the sound insulation sponge is reinforced by an adjusting component, so that the sound insulation sponge is more closely fitted to the outer wall of the rectangular air duct, thereby increasing its noise blocking effect.

[0016] 2. The present invention sets a support mechanism and uses the screws on both sides to push synchronously, so that the first sliding frame moves toward the second fixed frame, thereby causing the first sliding frame to exert an extrusion effect on the second rotating rod by means of the first rotating rod, so that the second sliding frame can slide along the fixed axis toward one side of the fixed block, and the second sliding frame can enable the pressure plate and the clamping rod to clamp and fix the sound insulation sponge at the same time.

[0017] 3. The present invention provides an arc rod and a clamping rod. When the second sliding frame slides toward one side of the fixed block, the end of the arc rod away from the fixed block flips toward one side of the connecting pipe, so that the sound insulation sponge on the outer wall of the connecting pipe is clamped and fixed by the clamping rod, thereby improving the convenience of reinforcing the sound insulation sponge.

[0018] 4. The present invention sets an adjustment component. When the second sliding frame slides toward one side of the fixed block, the second connecting rod flips with the second fixed frame as the center. After the sound insulation sponge is squeezed by the pressing plate, the pressing plate is adjusted to a certain angle through the connecting shaft, thereby increasing the contact area between the pressing plate and the sound insulation sponge, and improving the squeezing force of the pressing plate on the sound insulation sponge, so that the sound insulation sponge and the outer wall of the rectangular air duct are more closely fitted. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings: Figure 1 It is a schematic diagram of the overall front structure of the present invention; Figure 2 It is a schematic diagram of the overall front cross-sectional structure of the present invention; Figure 3 It is a schematic diagram of the supporting mechanism and adjusting assembly structure of the present invention; Figure 4 For the present invention Figure 2A is a schematic diagram of the enlarged structure of the middle part; Figure 5 It is a schematic diagram of the support mechanism structure of the present invention; Figure 6 It is a schematic diagram of the support mechanism structure of the present invention; Figure 7 It is a schematic diagram of the structure of the regulating component of the present invention; Figure 8 It is a schematic diagram of the structure of the regulating component of the present invention.

[0020] In the figure: 1. supporting mechanism; 101. first fixed frame; 102. elastic component; 103. second fixed frame; 104. first sliding frame; 105. first rotating rod; 106. screw rod; 107. fixed shaft; 108. second rotating rod; 109. fixed block; 110. arc rod; 111. first through hole; 112. clamping rod; 113. first spring; 2. adjusting component; 201. second sliding frame; 202. first connecting rod; 203. second spring; 204. second connecting rod; 205. second through hole; 206. pressing plate; 207. third through hole; 208. connecting shaft; 209. limiting plate; 210. third spring; 301. connecting pipe; 302. flange; 303. sealing ring; 304. sound absorbing board. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0022] Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0023] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0024] Example 1: See Figure 1-Figure 6The present invention provides a technical solution: a pipe wall noise reduction and reinforcement structure, including a support mechanism 1, the support mechanism 1 includes a first fixed frame 101, the outer wall of the first fixed frame 101 is fixedly connected with an elastic component 102, the elastic component 102 is made of rubber and has a certain vibration reduction and noise reduction effect, the outer wall of the first fixed frame 101 away from the elastic component 102 is fixedly connected with a second fixed frame 103, the outer wall of the second fixed frame 103 away from the first fixed frame 101 is fixedly connected with a flange 302, thereby improving the stability of the second fixed frame 103, a first sliding frame 104 is arranged on the top of the second fixed frame 103, the inner wall of the first sliding frame 104 is rotatably connected with a screw 106, one end of the screw 106 away from the first sliding frame 104 is rotatably connected with the outer wall of the connecting pipe 301, and the distance between the first sliding frame 104 and the connecting pipe 301 can be adjusted by rotating the screw 106, and the outer wall of the second fixed frame 103 is fixedly connected with a fixed shaft 107, and also includes: The adjusting component 2 includes a second sliding frame 201 slidably connected to the fixed shaft 107, a second connecting rod 204 is arranged on the inner wall of the second sliding frame 201, a second spring 203 is fixedly connected to the outer wall of the second sliding frame 201 on one side close to the second fixed frame 103, an end of the second spring 203 away from the second sliding frame 201 is fixedly connected to the second fixed frame 103, and the inner wall of the second sliding frame 201 on one side close to the second fixed frame 103 is rotatably connected to the first connecting rod 202 via a rotating shaft. During the operation of the fan, the rectangular air duct is reinforced by the supporting mechanism 1, and the vibration generated by the fan during operation is absorbed by the elastic component 102 between the first fixed frame 101 and the second fixed frame 103. The sound insulation sponge is reinforced by the adjusting component 2, so that the sound insulation sponge fits more closely to the outer wall of the rectangular air duct, thereby enhancing its noise blocking effect.

[0025] The outer wall of the first sliding frame 104 is rotatably connected to the first rotating rod 105 via a rotating shaft, and the end of the first rotating rod 105 away from the first sliding frame 104 is rotatably connected to the second rotating rod 108 via a rotating shaft. The first sliding frame 104 approaches one side of the second fixed frame 103 under the action of the screw 106, so that the first sliding frame 104 squeezes the second rotating rod 108 through the first rotating rod 105 at the same time, and the end of the second rotating rod 108 away from the first rotating rod 105 is rotatably connected to the second fixed frame 103.

[0026] One end of the fixed shaft 107 away from the second fixed frame 103 is fixedly connected to a fixed block 109, and the inner wall of the fixed block 109 is fixedly connected to an arc rod 110. The inner wall of the arc rod 110 is provided with a first through hole 111, and the inner wall of the first through hole 111 is slidably connected to the second sliding frame 201. As the second sliding frame 201 slides toward the fixed block 109, the end of the arc rod 110 away from the fixed block 109 flips toward the connecting tube 301, and then the sound insulation sponge on the outer wall of the connecting tube 301 is clamped and fixed by the clamping rod 112, thereby improving the convenience of the sound insulation sponge reinforcement operation.

[0027] The end of the arc rod 110 away from the fixed block 109 is rotatably connected to the clamping rod 112 through a rotating shaft, and the outer wall of the clamping rod 112 close to the arc rod 110 is fixedly connected to the first spring 113. The angle of the clamping rod 112 is adjusted by the first spring 113, so that the sound insulation sponge on the outer wall of the connecting pipe 301 can be fixed more conveniently. The end of the first spring 113 away from the clamping rod 112 is fixedly connected to the arc rod 110, and the screw rods 106 on both sides synchronously push the first sliding frame 104 to move toward the second fixed frame 103, thereby allowing the first sliding frame 104 to apply a squeezing effect to the second rotating rod 108 by relying on the first rotating rod 105, so that the second sliding frame 201 can slide along the fixed axis 107 toward the side of the fixed block 109, and the second sliding frame 201 can realize the operation of clamping and fixing the sound insulation sponge simultaneously by the pressure plate 206 and the clamping rod 112.

[0028] The working principle of this embodiment is as follows: when the sound insulation sponge is used to reinforce the outer wall of the connecting tube 301, the sound insulation sponge is first completely wrapped around the outer wall of the connecting tube 301. Then, the screws 106 on both sides are rotated in the same direction at the same time. Driven by this action, the first sliding frame 104 begins to slide slowly toward one side of the connecting tube 301. As the first sliding frame 104 gradually descends, its outer wall exerts a strong squeeze on the second rotating rod 108 through the tightly connected first rotating rod 105. This squeeze is transmitted. When the second rotating rod 108 squeezes the first connecting rod 202, a chain reaction is triggered, so that the second sliding frame 201 slides smoothly along the fixed axis 107 toward one side of the fixed block 109. During the entire sliding process of the second sliding frame 201, the second spring 203 is continuously stretched and a certain amount of elastic potential energy is accumulated. When the second sliding frame 201 continues to slide toward the side of the fixed block 109, the arc rod 110 moves away from the first rotating rod 108. One end of the fixing block 109 is flipped toward the side of the connecting pipe 301. At this time, the sound insulation sponge on the outer wall of the connecting pipe 301 can be effectively clamped and fixed by the clamping rod 112. When the clamping rod 112 and the sound insulation sponge are in contact with each other, the clamping rod 112 will cause a certain degree of extrusion on the first spring 113. By means of this extrusion, the angle of the clamping rod 112 can be flexibly adjusted by the first spring 113. In this way, the contact area of ​​the clamping rod 112 on the sound insulation sponge is greatly improved, so that the sound insulation sponge can fit more closely with the outer wall of the rectangular air duct to achieve excellent sound insulation effect. When the sound insulation sponge needs to be replaced later, it is only necessary to rotate the screws 106 on both sides to cause the first sliding frame 104 to slide upward. In this way, the fixing state of the clamping rod 112 on the sound insulation sponge can be released, so that the sound insulation sponge can be replaced smoothly to ensure that the sound insulation device is always in good working condition.

[0029] Example 2: Please refer to Figure 7-Figure 8 On the basis of the first embodiment, the present invention provides a technical solution: the inner wall of the second connecting rod 204 away from the second sliding frame 201 is rotatably connected to the second fixed frame 103, the inner wall of the second connecting rod 204 is provided with a second through hole 205, the outer wall of the second connecting rod 204 away from the second fixed frame 103 is rotatably connected with a pressure plate 206 through a rotating shaft, the inner wall of the second through hole 205 is slidably connected to the second sliding frame 201, and the pressure plate 206 applies different forces to the sound insulation sponge according to the different distances between the second sliding frame 201 and the second fixed frame 103.

[0030] A third through hole 207 is formed on the inner wall of the pressing plate 206 close to the second fixing frame 103, and a connecting shaft 208 is fixedly connected to the outer wall of the pressing plate 206 close to the second fixing frame 103. The connecting shaft 208 makes the pressing plate 206 close to the second fixing frame 103 more stable during movement.

[0031] One end of the connecting shaft 208 away from the pressure plate 206 passes through the second connecting rod 204 and is fixedly connected to the limiting plate 209. The outer wall of the limiting plate 209 close to the second connecting rod 204 is fixedly connected with a third spring 210. The third spring 210 is used for resetting the pressure plate 206. One end of the third spring 210 away from the limiting plate 209 is fixedly connected to the second connecting rod 204. When the second sliding frame 201 slides toward the side of the fixed block 109, the second connecting rod 204 is flipped with the second fixed frame 103 as the axis. After the sound insulation sponge is squeezed by the pressure plate 206, the pressure plate 206 is adjusted to a certain angle with the help of the connecting shaft 208, thereby increasing the contact area between the pressure plate 206 and the sound insulation sponge, enhancing the squeezing force of the pressure plate 206 on the sound insulation sponge, and making the sound insulation sponge fit more closely to the outer wall of the rectangular air duct.

[0032] The working principle of this embodiment is as follows: in the process of the second sliding frame 201 moving toward the side of the fixed block 109, a sliding connection is formed between the outer wall of the second sliding frame 201 and the second through hole 205 on the inner wall of the second connecting rod 204. Under this action, the second connecting rod 204 can be flipped with the first fixed frame 101 as the center point. Then, the sound insulation sponge on the outer wall of the connecting tube 301 is squeezed and fixed by the pressing plate 206 at the bottom of the second connecting rod 204. When the second connecting rod 204 continues to flip toward the side of the connecting tube 301, the side of the pressing plate 206 close to the first fixed frame 101 will first contact the sound insulation sponge. As the second connecting rod 204 continues to act, the pressing plate 206 gradually expands the contact area with the sound insulation sponge. This gradually increasing contact area effectively enhances the squeezing force of the pressure plate 206 on the sound insulation sponge, thereby causing the sound insulation sponge to fit more closely to the outer wall of the rectangular air duct, thereby achieving better sound insulation effect. However, when the pressure plate 206 squeezes the sound insulation sponge excessively, the side of the pressure plate 206 close to the first fixing frame 101 will slide through the connecting shaft 208. This sliding action can cleverly avoid excessive squeezing of the sound insulation sponge by the side of the pressure plate 206 close to the first fixing frame 101, thereby protecting the sound insulation sponge from damage, while also ensuring the rationality and stability of the entire squeezing and fixing process, so that the sound insulation sponge can achieve a good fitting effect while not affecting its performance and service life due to excessive squeezing.

[0033] A rectangular air duct includes: a connecting pipe 301, the outer wall of the connecting pipe 301 is fixedly connected to a first fixing frame 101, the outer wall of the connecting pipe 301 is fixedly connected to a flange 302, the end of the flange 302 away from the connecting pipe 301 is fixedly connected to a sealing ring 303, and the inner wall of the connecting pipe 301 is fixedly connected to a sound absorbing panel 304.

[0034] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0035] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A pipe wall noise reduction and reinforcement structure, comprising a support mechanism (1), the support mechanism (1) comprising a first fixed frame (101), an outer wall of the first fixed frame (101) being fixedly connected to an elastic component (102), an outer wall of the first fixed frame (101) being fixedly connected to a second fixed frame (103) on a side away from the elastic component (102), a first sliding frame (104) being arranged on the top of the second fixed frame (103), an inner wall of the first sliding frame (104) being rotatably connected to a screw rod (106), and an outer wall of the second fixed frame (103) being fixedly connected to a fixed shaft (107), characterized in that: Also included are: The adjustment assembly (2) comprises a second sliding frame (201) slidably connected to a fixed shaft (107); a second connecting rod (204) is arranged on an inner wall of the second sliding frame (201); a second spring (203) is fixedly connected to an outer wall of the second sliding frame (201) on a side close to the second fixed frame (103); an end of the second spring (203) away from the second sliding frame (201) is fixedly connected to the second fixed frame (103); and an inner wall of the second sliding frame (201) on a side close to the second fixed frame (103) is rotatably connected to the first connecting rod (202) via a rotating shaft.

2. A pipe wall noise reduction and reinforcement structure according to claim 1, characterized in that: The outer wall of the first sliding frame (104) is rotatably connected to a first rotating rod (105) via a rotating shaft; one end of the first rotating rod (105) away from the first sliding frame (104) is rotatably connected to a second rotating rod (108) via a rotating shaft; and one end of the second rotating rod (108) away from the first rotating rod (105) is rotatably connected to the second fixed frame (103).

3. The pipe wall noise reduction and reinforcement structure according to claim 1, characterized in that: The inner wall of the second connecting rod (204) at one side away from the second sliding frame (201) is rotatably connected to the second fixed frame (103), and a second through hole (205) is formed on the inner wall of the second connecting rod (204).

4. A pipe wall noise reduction and reinforcement structure according to claim 3, characterized in that: The outer wall of the second connecting rod (204) at one side away from the second fixed frame (103) is rotatably connected to a pressing plate (206) via a rotating shaft, and the inner wall of the second through hole (205) is slidably connected to the second sliding frame (201).

5. The pipe wall noise reduction and reinforcement structure according to claim 4, characterized in that: A third through hole (207) is provided on an inner wall of the pressing plate (206) close to the second fixing frame (103), and a connecting shaft (208) is fixedly connected to an outer wall of the pressing plate (206) close to the second fixing frame (103).

6. The pipe wall noise reduction and reinforcement structure according to claim 5, characterized in that: One end of the connecting shaft (208) away from the pressing plate (206) passes through the second connecting rod (204) and is fixedly connected to the limiting plate (209).

7. The pipe wall noise reduction and reinforcement structure according to claim 6, characterized in that: A third spring (210) is fixedly connected to an outer wall of one side of the limiting plate (209) close to the second connecting rod (204), and one end of the third spring (210) away from the limiting plate (209) is fixedly connected to the second connecting rod (204).

8. The pipe wall noise reduction and reinforcement structure according to claim 7, characterized in that: One end of the fixed shaft (107) away from the second fixed frame (103) is fixedly connected to a fixed block (109); an inner wall of the fixed block (109) is fixedly connected to an arc-shaped rod (110); a first through hole (111) is formed on the inner wall of the arc-shaped rod (110); and the inner wall of the first through hole (111) is slidably connected to the second sliding frame (201).

9. The pipe wall noise reduction and reinforcement structure according to claim 8, characterized in that: One end of the arc-shaped rod (110) away from the fixed block (109) is rotatably connected to a clamping rod (112) via a rotating shaft; a first spring (113) is fixedly connected to an outer wall of a side of the clamping rod (112) close to the arc-shaped rod (110); and one end of the first spring (113) away from the clamping rod (112) is fixedly connected to the arc-shaped rod (110).

10. A rectangular air duct, characterized in that: include: A connecting pipe (301), the outer wall of the connecting pipe (301) being fixedly connected to the first fixing frame (101), the outer wall of the connecting pipe (301) being fixedly connected to a flange (302), one end of the flange (302) away from the connecting pipe (301) being fixedly connected to a sealing ring (303), and the inner wall of the connecting pipe (301) being fixedly connected to a sound absorbing panel (304).

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