Large-air-volume low-noise air supply device based on composite air duct collaborative noise reduction

Abstract

The invention belongs to the technical field of air feeders, and discloses a large-air-volume low-noise air supply device based on composite air duct collaborative noise reduction, which comprises an air feeder shell, and further comprises a centrifugal fan unit arranged in the air feeder shell; according to the technical scheme, by arranging the noise reduction plate set, the buffering assembly and the hydraulic assembly, when the centrifugal fan set operates, air can enter the interior in a centrifugal mode and enter the top air opening in one side, air pressure can be concentrated on the top, the noise reduction plate set on the top is pushed upwards, at the moment, the buffering assembly and a buffering spring can buffer the large air pressure, and the noise reduction effect is improved. Hydraulic oil in the buffer assembly drives hydraulic oil in the communication groove to enter the hydraulic assembly, then the noise reduction plate sets at the bottom are driven to move downwards and are buffered through the buffer springs, finally, the upper noise reduction plate set and the lower noise reduction plate set move the same distance to keep air pressure balance, the air pressure is balanced smoothly, and the purposes of buffering, damping and noise reduction are achieved; damage to the shell is reduced, and the service life is prolonged.

Description

Technical Field

[0001] The present invention belongs to the technical field of air blowers, and specifically is a large air volume and low noise air supply device based on composite air duct collaborative noise reduction. Background Art

[0002] The high-volume, low-noise air supply device based on composite air duct collaborative noise reduction is an innovative solution developed in the current field of ventilation technology to meet the needs of high efficiency and quietness. It absorbs medium and high-frequency noise by laying sound-absorbing materials (such as glass wool, polyurethane foam) on the inner wall of the air duct with a thickness of ≥50mm. The high-volume air supply device is a type of air delivery equipment that focuses on high air volume output and optimized airflow distribution. It is widely used in industrial, commercial and civil fields.

[0003] The noise of existing large-volume air supply devices mainly comes from the fact that when the airflow is delivered upward through the rotation of the centrifugal impeller, a large amount of wind pressure is concentrated on the top, resulting in uneven pressure on the casing during air supply, causing the casing to vibrate and produce noise. The noise reduction is achieved through sound-absorbing materials and silencers, but it is impossible to eliminate the vibration of the casing caused by uneven wind pressure from the root, which will cause damage to the casing and reduce its service life. Therefore, it needs to be improved. Summary of the invention

[0004] In order to solve the problems raised in the above background technology, the present invention provides a large-volume, low-noise air supply device based on composite air duct collaborative noise reduction, which has the advantages of buffering and balancing wind pressure noise reduction.

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solutions: a large-volume, low-noise air supply device based on composite air duct collaborative noise reduction, comprising a blower housing, and also comprising: a centrifugal fan group, which is arranged inside the blower housing; a noise reduction mechanism, which is arranged on one side of the top of the inner cavity of the centrifugal fan group; wherein the noise reduction mechanism comprises a noise reduction plate group arranged at the top of the inner cavity of the centrifugal fan group, the outer end of the noise reduction plate group is elastically connected to the inner cavity of the centrifugal fan group through a buffer spring, a buffer component is arranged on the top of the noise reduction plate group, and the buffer component is located on the inner side of the buffer spring, a hydraulic component is arranged on the bottom of the noise reduction plate group, and the hydraulic component is located on the inner side of the buffer spring, and the buffer component is connected to the hydraulic component through a connecting groove.

[0006] Preferably, a composite air duct is provided at the top of one end of the centrifugal fan unit.

[0007] Preferably, the surface of the blower housing is provided with an air inlet mesh plate located on one side of the centrifugal fan unit.

[0008] Preferably, the noise reduction plate group includes a sliding sleeve, a noise reduction plate, a first telescopic plate and a first spring; The sliding sleeve is arranged on one side of the top of the inner cavity of the centrifugal fan unit, and the noise reduction plate is slidably connected to the inner cavity of the sliding sleeve through a first telescopic plate movably installed at the end, and the inner end of the first telescopic plate is elastically connected to the end of the noise reduction plate through a first spring.

[0009] Preferably, the buffer assembly comprises a first hydraulic cylinder, a movable plate and a sealing valve disc; The first hydraulic cylinder is arranged inside the centrifugal fan unit, and the first hydraulic cylinder is located on the inner side of the noise reduction plate, the movable plate is movably installed at the bottom of the inner cavity of the first hydraulic cylinder, the sealing valve flap is arranged inside the noise reduction plate, and the sealing valve flap is located directly below the first hydraulic cylinder.

[0010] Preferably, the sealing valve flap is made of rubber.

[0011] Preferably, the hydraulic assembly includes a second hydraulic cylinder, a hydraulic piston rod and a connecting pipe; The second hydraulic cylinder is fixedly installed inside the centrifugal fan unit, and the second hydraulic cylinder is located below the noise reduction plate. The hydraulic piston rod is movably installed in the inner cavity of the second hydraulic cylinder, and the top of the hydraulic piston rod is fixedly connected to the inner wall of the noise reduction plate. The second hydraulic cylinder is connected to the connecting groove through a connecting pipe.

[0012] Preferably, a sliding assembly is provided at the end of the first telescopic plate, and the sliding assembly includes a sliding roller and a sealing strip; The sliding rollers are arranged at both sides of the end of the first telescopic plate, and the outer ends of the sliding rollers are rollingly connected to the inner wall of the sliding sleeve seat, and the sealing strip is arranged at the inner end of the sliding sleeve seat.

[0013] Preferably, a buffer mechanism is provided inside the centrifugal fan unit and is located at the top of one side of the noise reduction plate group, and the buffer mechanism includes a buffer plate group, an air pressure cylinder and a pneumatic piston rod; The buffer plate group is movably sleeved on the top of the inner cavity of the centrifugal fan group, the air pressure cylinder is fixedly installed inside the blower housing, and the air pressure cylinder is located above the buffer plate group, the pneumatic piston rod is arranged on the top of the buffer plate group, and the top end of the pneumatic piston rod extends to the inside of the air pressure cylinder.

[0014] Preferably, the buffer plate group includes a buffer plate, a second telescopic plate and a second spring; The buffer plate is movably sleeved on the top of the inner cavity of the centrifugal fan unit, and the second telescopic plate is movably installed in the inner cavity at the end of the buffer plate. The second telescopic plate is elastically connected to the inside of the buffer plate through a second spring.

[0015] Compared with the prior art, the present invention has the following beneficial effects: The above technical solution is provided with a noise reduction plate group, a buffer assembly and a hydraulic assembly. When the centrifugal fan unit is running, the wind can enter the interior centrifugally and enter through the top air outlet on one side, and the wind pressure will be concentrated on the top, thereby pushing the top noise reduction plate group upward. At this time, the buffer assembly and the buffer spring will buffer the larger wind pressure, and then the hydraulic oil in the buffer assembly will drive the hydraulic oil in the connecting groove to enter the hydraulic assembly, and then drive the bottom noise reduction plate group downward and buffer through the buffer spring. Finally, the upper and lower noise reduction plate groups move the same distance to maintain wind pressure balance, so that the wind pressure can be smoothly balanced, achieving the purpose of buffering, shock absorption and noise reduction, reducing damage to the shell and improving service life.

[0016] The present invention provides a buffer plate group, an air cylinder and a pneumatic piston rod. The centrifugal fan group is operated to centrifugally rotate to guide the external wind into the interior, and enters the top of the guide side, so that the buffer plate group is driven to deflect, and the pneumatic piston rod is squeezed and moved, and then the gas inside the air cylinder is compressed. At this time, the gas inside the air cylinder can pre-buffer the concentrated upward wind pressure, thereby realizing pre-buffering and shock reduction of the top.

[0017] The present invention provides a noise reduction plate group, a sliding roller and a sealing strip. The noise reduction plate group is driven by wind pressure to extend and retract the end portion, which causes the sliding roller to roll along the inside of the noise reduction plate group, so that sliding friction is converted into rolling friction, thereby greatly improving the smoothness of sliding. In addition, the sealing strip can maintain the sealing performance of the end portion of the noise reduction plate group when sliding. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the structure of the present invention; Figure 2 It is a cross-sectional schematic diagram of the centrifugal fan unit of the present invention; Figure 3 It is a schematic diagram of the cross-sectional structure of the composite air duct pipe of the present invention; Figure 4 It is a schematic cross-sectional structural diagram of the buffer assembly of the present invention; Figure 5 for Figure 4 A schematic diagram of the local enlarged structure at point A in the middle; Figure 6 for Figure 4 A schematic diagram of the local enlarged structure at B in the middle; Figure 7 It is a cross-sectional structural schematic diagram of the noise reduction mechanism of the present invention; Figure 8 for Figure 7 A schematic diagram of the local enlarged structure at C in the middle; Fig. 9 It is a schematic structural diagram of the buffer spring of the present invention; Fig.10 for Fig. 9Schematic diagram of the local enlarged structure at point D in the middle.

[0019] In the figure: 1. blower housing; 2. centrifugal fan unit; 3. composite air duct; 4. air inlet mesh; 5. noise reduction mechanism; 501. noise reduction plate group; 5011. sliding sleeve; 5012. noise reduction plate; 5013. first telescopic plate; 5014. first spring; 502. buffer spring; 503. buffer assembly; 5031. first hydraulic cylinder; 5032. movable plate; 5033. sealing valve disc; 504. hydraulic assembly; 5041. second hydraulic cylinder; 5042. hydraulic piston rod; 5043. connecting pipe; 505. connecting groove; 6. sliding assembly; 601. sliding roller; 602. sealing strip; 7. buffer mechanism; 701. buffer plate group; 7011. buffer plate; 7012. second telescopic plate; 7013. second spring; 702. air cylinder; 703. pneumatic piston rod. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] like Figures 1 to 10 As shown, the present invention provides a large-volume, low-noise air supply device based on composite air duct collaborative noise reduction, including a blower housing 1, and also including: a centrifugal fan group 2, which is arranged inside the blower housing 1; a noise reduction mechanism 5, which is arranged on one side of the top of the inner cavity of the centrifugal fan group 2; wherein the noise reduction mechanism 5 includes a noise reduction plate group 501 arranged at the top of the inner cavity of the centrifugal fan group 2, the outer end of the noise reduction plate group 501 is elastically connected to the inner cavity of the centrifugal fan group 2 through a buffer spring 502, a buffer component 503 is arranged at the top of the noise reduction plate group 501, and the buffer component 503 is located on the inner side of the buffer spring 502, a hydraulic component 504 is arranged at the bottom of the noise reduction plate group 501, and the hydraulic component 504 is located on the inner side of the buffer spring 502, and the buffer component 503 is connected with the hydraulic component 504 through a connecting groove 505.

[0022] Through the operation of the centrifugal fan unit 2, the external wind can be centrifugally drawn into the inner part and concentrated to the top of one side, which will cause the top noise reduction plate group 501 to absorb the pressure upward through the buffer component 503 and the buffer spring 502, and then the hydraulic oil inside the buffer component 503 pushes the hydraulic oil in the connecting groove 505 to be introduced into the hydraulic component 504 to drive the bottom noise reduction plate group 501 downward, so that the two noise reduction plate groups 501 move the same distance and are under the same pressure, ultimately achieving the purpose of wind pressure balance.

[0023] like Figure 1 and Figure 3 As shown, a composite air duct 3 is arranged on the top of one end of the centrifugal fan unit 2.

[0024] The above solution is adopted: by providing a composite air duct pipe 3, the composite air duct pipe 3 is composed of a variety of composite materials, mainly sound-absorbing materials, and the length material requirements are mainly designed according to actual conditions.

[0025] like Figure 1 and Figure 2 As shown, the surface of the blower housing 1 is provided with an air inlet mesh plate 4 located on one side of the centrifugal fan unit 2 .

[0026] By adopting the above solution, the air intake mesh plate 4 is designed to filter the gas centrifugally sucked in by the centrifugal fan unit 2, thereby effectively blocking large particles and dust.

[0027] like Figure 6 , Figure 7 and Fig. 9 As shown, the noise reduction plate assembly 501 includes a sliding sleeve 5011, a noise reduction plate 5012, a first telescopic plate 5013 and a first spring 5014; The sliding sleeve 5011 is arranged on one side of the top of the inner cavity of the centrifugal fan unit 2, and the noise reduction plate 5012 is slidingly connected to the inner cavity of the sliding sleeve 5011 through a first telescopic plate 5013 movably installed at the end, and the inner end of the first telescopic plate 5013 is elastically connected to the end of the noise reduction plate 5012 through a first spring 5014.

[0028] The above solution is adopted: by providing a first spring 5014, the elastic force of the first spring 5014 can assist in pushing the noise reduction plate 5012 to move outward, and assist in pushing the first telescopic plate 5013 to move backward, so as to maintain the purpose of limiting the movement of the noise reduction plate 5012.

[0029] like Figure 4 and Figure 7 As shown, the buffer assembly 503 includes a first hydraulic cylinder 5031, a movable plate 5032 and a sealing valve disc 5033; The first hydraulic cylinder 5031 is arranged inside the centrifugal fan unit 2, and the first hydraulic cylinder 5031 is located on the inner side of the noise reduction plate 5012, the movable plate 5032 is movably installed at the bottom of the inner cavity of the first hydraulic cylinder 5031, and the sealing valve flap 5033 is arranged inside the noise reduction plate 5012, and the sealing valve flap 5033 is located directly below the first hydraulic cylinder 5031.

[0030] The above scheme is adopted: by providing a movable plate 5032, when the wind pressure is concentrated on the top and pushes the top noise reduction plate group 501 to move upward, the bottom end of the first hydraulic cylinder 5031 will squeeze and push the sealing valve flap 5033 to open, and then push the movable plate 5032 upward, so that the hydraulic oil in the inner cavity of the movable plate 5032 is introduced into the connecting groove 505, so that the hydraulic oil in the connecting groove 505 becomes larger and enters into the hydraulic assembly 504.

[0031] like Figure 4 and Figure 7 As shown, the sealing valve flap 5033 is made of rubber.

[0032] The above solution is adopted: by providing the sealing valve flap 5033, since rubber has good elastic recovery ability, when the sealing valve flap 5033 is released and flipped open, the bottom seal of the first hydraulic cylinder 5031 can be restored.

[0033] like Figure 7 and Figure 8 As shown, the hydraulic assembly 504 includes a second hydraulic cylinder 5041, a hydraulic piston rod 5042 and a connecting pipe 5043; The second hydraulic cylinder 5041 is fixedly installed inside the centrifugal fan unit 2, and the second hydraulic cylinder 5041 is located below the noise reduction plate 5012, the hydraulic piston rod 5042 is movably installed in the inner cavity of the second hydraulic cylinder 5041, and the top of the hydraulic piston rod 5042 is fixedly connected to the inner wall of the noise reduction plate 5012, and the second hydraulic cylinder 5041 is connected to the connecting groove 505 through the connecting pipe 5043.

[0034] The above scheme is adopted: by providing a connecting pipe 5043, when the hydraulic oil in the connecting groove 505 increases, the hydraulic oil at the bottom will be introduced into the second hydraulic cylinder 5041 through the connecting pipe 5043, so that the hydraulic pressure in the top inner cavity of the second hydraulic cylinder 5041 increases and pushes the hydraulic piston rod 5042 and the noise reduction plate 5012 downward, so as to balance the pressure on the two noise reduction plate groups 501 as a whole.

[0035] like Fig.10 As shown, a sliding assembly 6 is provided at the end of the first telescopic plate 5013, and the sliding assembly 6 includes a sliding roller 601 and a sealing strip 602; The sliding rollers 601 are arranged on both sides of the ends of the first telescopic plate 5013 , and the outer ends of the sliding rollers 601 are rollingly connected to the inner wall of the sliding sleeve 5011 , and the sealing strip 602 is arranged at the inner end of the sliding sleeve 5011 .

[0036] By adopting the above solution, by providing the sliding roller 601, when the end of the first telescopic plate 5013 moves inside the sliding sleeve 5011, the sliding roller 601 will convert the sliding friction into rolling friction, thereby reducing the friction force and improving the smoothness of movement.

[0037] like Figure 4 and Figure 5 As shown, a buffer mechanism 7 is provided inside the centrifugal fan unit 2 at the top of one side of the noise reduction plate group 501, and the buffer mechanism 7 includes a buffer plate group 701, an air pressure cylinder 702 and a pneumatic piston rod 703; The buffer plate group 701 is movably sleeved on the top of the inner cavity of the centrifugal fan group 2, the air pressure cylinder 702 is fixedly installed inside the blower housing 1, and the air pressure cylinder 702 is located above the buffer plate group 701, and the pneumatic piston rod 703 is arranged on the top of the buffer plate group 701, and the top end of the pneumatic piston rod 703 extends to the inside of the air pressure cylinder 702.

[0038] The above scheme is adopted: by providing an air pressure cylinder 702, since there is gas inside the air pressure cylinder 702, when the buffer plate group 701 is driven to rotate by wind pressure, the top of the pneumatic piston rod 703 slides inside the air pressure cylinder 702 to compress the gas. At this time, the gas can buffer the wind pressure and reduce the vibration effect on the centrifugal fan unit 2 as a whole.

[0039] like Figure 4 and Figure 5 As shown, the buffer plate set 701 includes a buffer plate 7011, a second telescopic plate 7012 and a second spring 7013; The buffer plate 7011 is movably sleeved on the top of the inner cavity of the centrifugal fan unit 2 , and the second telescopic plate 7012 is movably installed in the inner cavity at the end of the buffer plate 7011 . The second telescopic plate 7012 is elastically connected to the inside of the buffer plate 7011 through the second spring 7013 .

[0040] The above scheme is adopted: in the initial state, the end of the second telescopic plate 7012 away from the buffer plate 7011 is tightly in contact with the inner wall of the centrifugal fan unit 2. At this time, the second spring 7013 is in a compressed state, and the buffer plate 7011 and the second telescopic plate 7012 block the middle area formed by the two noise reduction plate groups 501. Then, due to the elastic force of the second spring 7013, the buffer plate 7011 can be pushed and deflected by the wind pressure, and the pneumatic piston rod 703 can be pushed out, so that the end portion is in smooth contact with the surface of one side of the top sliding sleeve 501, ensuring that the wind pressure can smoothly enter between the noise reduction plate groups 501.

[0041] The working principle and use process of the present invention: First, when the centrifugal fan unit 2 is started, the external wind will be centrifugally filtered through the air inlet mesh plate 4 and introduced into the interior of the centrifugal fan unit 2, and then concentratedly guided to the top of one side, thereby pushing the buffer plate group 701 to rotate and flip open as a whole. At this time, due to the elastic force of the second spring 7013, the second telescopic plate 7012 can be pushed out, so that the subsequent end of the buffer plate group 701 can contact one side of the top sliding sleeve 5011, so that the wind is smoothly guided to the middle area of ​​the two noise reduction plate groups 501. Since the buffer plate group 701 is flipped, it will drive the pneumatic piston rod 703 to move and squeeze the gas in the inner cavity of the air pressure cylinder 702, thereby achieving preliminary buffering of the concentrated wind pressure.

[0042] Then, the concentrated upward wind pressure will squeeze and push the top noise reduction plate 5012 to move upward, and the first telescopic plate 5013 can be driven to move in opposite directions through the auxiliary effect of the elastic force of the first spring 5014, and the sealing strip 602 at the end of the first telescopic plate 5013 will roll along the inclined surface of the inner cavity of the sliding sleeve 5011 to achieve the purpose of limiting the noise reduction plate 5012, and then the elastic force of the buffer spring 502 can buffer the wind pressure.

[0043] Finally, since the noise reduction plate 5012 is upward, the bottom end of the first hydraulic cylinder 5031 will push the sealing valve flap 5033 downward to open, releasing the seal on the bottom of the first hydraulic cylinder 5031, and the wind pressure will enter the first hydraulic cylinder 5031, thereby pushing the movable plate 5032 upward, and then pushing the hydraulic oil in the first hydraulic cylinder 5031 upward to the inside of the connecting groove 505, so that the liquid surface inside the connecting groove 505 is upward and the hydraulic oil is passed through the connecting pipe 5043 to the top of the inner cavity of the second hydraulic cylinder 5041, and then the hydraulic piston rod 5042 can be pushed to drive the bottom noise reduction plate group 501 downward as a whole, so that the force on the noise reduction plate group 501 is finally balanced, and the back-to-back buffering at the same distance occurs, which greatly reduces the vibration noise.

[0044] 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.

[0045] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A large air volume and low noise air supply device based on composite air duct collaborative noise reduction, comprising an air supply fan housing (1), characterized in that: Also includes: A centrifugal fan unit (2), wherein the centrifugal fan unit (2) is arranged inside the blower housing (1); A noise reduction mechanism (5), the noise reduction mechanism (5) being arranged on one side of the top of the inner cavity of the centrifugal fan unit (2); The noise reduction mechanism (5) comprises a noise reduction plate group (501) arranged at the top of the inner cavity of the centrifugal fan group (2); the outer end of the noise reduction plate group (501) is elastically connected to the inner cavity of the centrifugal fan group (2) via a buffer spring (502); a buffer component (503) is arranged at the top of the noise reduction plate group (501), and the buffer component (503) is located on the inner side of the buffer spring (502); a hydraulic component (504) is arranged at the bottom of the noise reduction plate group (501), and the hydraulic component (504) is located on the inner side of the buffer spring (502); and the buffer component (503) is connected to the hydraulic component (504) via a connecting groove (505).

2. The large air volume and low noise air supply device based on composite air duct collaborative noise reduction according to claim 1 is characterized in that: A composite air duct pipe (3) is arranged at the top of one end of the centrifugal fan unit (2).

3. The large air volume and low noise air supply device based on composite air duct collaborative noise reduction according to claim 1 is characterized in that: The surface of the blower housing (1) is provided with an air intake mesh plate (4) located on one side of the centrifugal blower unit (2).

4. The large air volume and low noise air supply device based on composite air duct collaborative noise reduction according to claim 1 is characterized in that: The noise reduction plate group (501) comprises a sliding sleeve (5011), a noise reduction plate (5012), a first telescopic plate (5013) and a first spring (5014); The sliding sleeve (5011) is arranged on one side of the top of the inner cavity of the centrifugal fan unit (2); the noise reduction plate (5012) is slidably connected to the inner cavity of the sliding sleeve (5011) via a first telescopic plate (5013) movably installed at the end; the inner end of the first telescopic plate (5013) is elastically connected to the end of the noise reduction plate (5012) via a first spring (5014).

5. The large air volume and low noise air supply device based on composite air duct collaborative noise reduction according to claim 1 is characterized in that: The buffer assembly (503) comprises a first hydraulic cylinder (5031), a movable plate (5032) and a sealing valve flap (5033); The first hydraulic cylinder (5031) is arranged inside the centrifugal fan unit (2), and the first hydraulic cylinder (5031) is located on the inner side of the noise reduction plate (5012); the movable plate (5032) is movably mounted on the bottom of the inner cavity of the first hydraulic cylinder (5031); the sealing valve flap (5033) is arranged inside the noise reduction plate (5012), and the sealing valve flap (5033) is located directly below the first hydraulic cylinder (5031).

6. The large air volume and low noise air supply device based on composite air duct collaborative noise reduction according to claim 5 is characterized in that: The sealing valve flap (5033) is made of rubber.

7. The large air volume and low noise air supply device based on composite air duct collaborative noise reduction according to claim 1 is characterized in that: The hydraulic assembly (504) comprises a second hydraulic cylinder (5041), a hydraulic piston rod (5042) and a connecting pipe (5043); The second hydraulic cylinder (5041) is fixedly installed inside the centrifugal fan unit (2), and the second hydraulic cylinder (5041) is located below the noise reduction plate (5012). The hydraulic piston rod (5042) is movably installed in the inner cavity of the second hydraulic cylinder (5041), and the top of the hydraulic piston rod (5042) is fixedly connected to the inner wall of the noise reduction plate (5012). The second hydraulic cylinder (5041) is connected to the connecting groove (505) via a connecting pipe (5043).

8. The large air volume and low noise air supply device based on composite air duct collaborative noise reduction according to claim 4 is characterized in that: A sliding assembly (6) is provided at the end of the first telescopic plate (5013), and the sliding assembly (6) comprises a sliding roller (601) and a sealing strip (602); The sliding roller (601) is arranged on both sides of the end of the first telescopic plate (5013), and the outer end of the sliding roller (601) is rollingly connected to the inner wall of the sliding sleeve (5011), and the sealing strip (602) is arranged at the inner end of the sliding sleeve (5011).

9. The large air volume and low noise air supply device based on composite air duct collaborative noise reduction according to claim 1 is characterized in that: The centrifugal fan unit (2) is provided with a buffer mechanism (7) located at the top of one side of the noise reduction plate group (501), and the buffer mechanism (7) comprises a buffer plate group (701), an air pressure cylinder (702) and a pneumatic piston rod (703); The buffer plate group (701) is movably sleeved on the top of the inner cavity of the centrifugal fan group (2), the air pressure cylinder (702) is fixedly installed inside the blower housing (1), and the air pressure cylinder (702) is located above the buffer plate group (701), the pneumatic piston rod (703) is arranged on the top of the buffer plate group (701), and the top end of the pneumatic piston rod (703) extends into the interior of the air pressure cylinder (702).

10. The large air volume and low noise air supply device based on composite air duct collaborative noise reduction according to claim 9, characterized in that: The buffer plate group (701) comprises a buffer plate (7011), a second telescopic plate (7012) and a second spring (7013); The buffer plate (7011) is movably sleeved on the top of the inner cavity of the centrifugal fan unit (2), and the second telescopic plate (7012) is movably installed in the inner cavity at the end of the buffer plate (7011). The second telescopic plate (7012) is elastically connected to the inside of the buffer plate (7011) via a second spring (7013).

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