Air volume keeping type silencer based on axial flow fan

Abstract

The invention discloses an air volume keeping type silencer based on an axial flow fan, relates to the technical field of axial flow fans, is used for solving the problem of conflict between air volume and noise of the axial flow fan at a high rotating speed, and is based on an outer shell, a transmission main shaft and turbine blades and takes an arc-shaped partition plate as a key structure, one end of the outer shell is provided with an arc-shaped air outlet, and a non-horizontal air channel is formed; the air channel is divided into a through air channel and a separation air channel through an arc-shaped partition plate, an air injection pipe, a semi-ventilation pipe and an airflow sensor are assembled on the arc-shaped partition plate, the air injection pipe is provided with an air injection air bag and a co-moving rubber sleeve, and an electrified electromagnetic assembly and a piston block are arranged in the semi-ventilation pipe. The air flow state is monitored in real time through the air flow sensor, the semi-ventilation pipe is triggered to be opened to achieve air flow division, the air injection air bag and the co-action rubber sleeve guide the divided air flow to be stably stacked, and on the premise that the blade rotating speed is not reduced and the exhaust air rate is guaranteed, vortex noise and air flow disturbance noise are restrained, and the air volume is not reduced.

Description

Technical Field

[0001] This invention relates to the field of axial flow fan technology, and more specifically to a volume-retaining silencer based on axial flow fans. Background Technology

[0002] The structure of an axial flow fan is not significantly different from that of a conventional fan. The difference lies in restricting the direction of airflow. The rotating impeller propels the gas like a propeller, allowing the gas to flow in a straight line along the fan axis. Its operation process has obvious disadvantages compared to conventional fans, namely the high noise generated during operation due to high wind noise, mechanical vibration, and airflow disturbance.

[0003] Assuming the overall structure is relatively stable, the main sources of noise are: when the blades rotate at high speed and cut the air, eddy noise is generated, especially in low-pressure axial flow fans, which is the main source of noise. Dust accumulation, deformation, or installation deviations on the blade edges can also cause airflow turbulence and increase wind noise. It can also be understood that the noise decibels are directly proportional to the blade rotation speed, and the blade rotation speed is directly proportional to the exhaust volume. If only the reduction of noise pollution in the workshop is considered, the workshop exhaust efficiency will inevitably be affected. In response to this problem, this invention proposes a solution. Summary of the Invention

[0004] The purpose of this invention is to provide a volume-retaining silencing device based on an axial flow fan. Without considering the shape of the blade structure and the installation strength, the higher the blade rotation speed, the higher the wind speed can be generated, but the noise generation will also be aggravated due to airflow disturbance and other problems.

[0005] The objective of this invention can be achieved through the following technical solution: a volume-retaining silencer based on an axial flow fan, comprising an outer shell, a drive shaft and turbine blades, wherein one end of the outer shell is configured as an arc-shaped air outlet, and a non-horizontal air passage is formed inside the outer shell through the arc-shaped air outlet, and an arc-shaped baffle is installed inside the outer shell corresponding to the arc-shaped air outlet. Corresponding to the non-horizontal air passage at the arc-shaped air outlet, an arc-shaped baffle forms a through air passage and a separate air passage. The arc-shaped baffle is equipped with a horizontally arranged air injection pipe and a semi-ventilation pipe respectively from top to bottom. An airflow sensor is provided on the outer wall of the arc-shaped baffle near the turbine blade. The position of the airflow sensor corresponds to the air injection pipe and the semi-ventilation pipe.

[0006] The configuration is further defined as follows: the transmission main shaft is arranged horizontally and passes through the arc-shaped partition, and the transmission main shaft and the arc-shaped partition are rotatably connected, and the turbine blade is installed at one end of the transmission main shaft.

[0007] The cross-section of the arc-shaped partition is curved to the left along the direction close to the arc-shaped air outlet.

[0008] The configuration is further defined as follows: an auxiliary pipe is arranged horizontally along the center point of the transmission main shaft, one end of the auxiliary pipe extends through to one end of the transmission main shaft and is equipped with an auxiliary impeller, and a second air groove is opened on the outer wall of the transmission main shaft corresponding to the position in the partition air passage.

[0009] A pressure-sensing piston assembly with a corresponding second air groove is further configured such that the inside of the transmission main shaft is located between the other end of the auxiliary passage pipe and the shaft.

[0010] The configuration is further defined as follows: the air injection pipe and the semi-ventilation pipe are positioned at different heights along the vertical direction, and the end of the air injection pipe and the semi-ventilation pipe corresponding to the air passage is open.

[0011] The configuration is further defined as follows: an air injection bladder and a cooperating rubber sleeve are respectively provided on the outer wall of the air separation channel corresponding to the air injection tube, and the cooperating rubber sleeve is symmetrically arranged along the position of the air injection bladder.

[0012] The following configuration is further provided: the airbag and the air tube are in a communication state, and a ball-head connector is provided at the intersection of the cooperating rubber sleeve and the air tube.

[0013] The configuration is further defined as follows: a first air groove is provided on the outer wall of the semi-ventilated pipe corresponding to the position of the dividing air passage, and an energized electromagnetic component and a piston block are respectively provided on both sides of the first air groove inside the semi-ventilated pipe.

[0014] The present invention has the following beneficial effects: Based on the structure of axial flow fans, an optimized method using arc-shaped baffles is first proposed. By constructing a smooth and curved main airflow channel through arc-shaped baffles, airflow impact and turbulence formation are reduced, and basic vortex noise is lowered. Combined with the active control method of airflow sensors and semi-ventilated pipes, the separation air passage is opened only when airflow disturbance intensifies and noise increases for diversion and adjustment. This method not only consumes airflow kinetic energy and avoids airflow collision through the flexible guidance of the air injection bag and the cooperating rubber sleeve, but also ensures that the main airflow channel is unobstructed under normal conditions, achieving a dynamic balance between "high speed, high air volume" and "low noise".

[0015] The overall structure does not require modification to the core transmission components and blade structure of the axial flow fan. Functional upgrades are achieved only through air duct optimization and airflow adjustment components, adapting to axial flow fan scenarios with different speed specifications. The mechanical structure and electronic control components work together. The passive fine-tuning of the pressure-sensing piston assembly and the active diversion of electromagnetic control are combined to adapt to changes in airflow pressure and avoid secondary disturbances. This is how the active airflow diversion method is proposed. In the process of active diversion, the combination of active "inflation" and natural swing of the rubber sleeve (in accordance with the airflow direction) can be used to further suppress noise generation by consuming the "kinetic energy" of the airflow. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the air volume retention type silencer device based on an axial flow fan proposed in this invention; Figure 2 For the present invention Figure 1 Cross-sectional view of the inner and outer shells; Figure 3 For the present invention Figure 2 The front view; Figure 4 This is a cross-sectional view of the air injection pipe corresponding to the arc-shaped partition in this invention; Figure 5 This is a cross-sectional view of the semi-ventilation pipe corresponding to the arc-shaped partition in this invention; Figure 6 This is a cross-sectional view of the transmission spindle in this invention.

[0018] In the diagram: 1. Outer shell; 2. Arc-shaped partition; 3. Drive shaft; 4. Turbine blades; 5. Semi-ventilation pipe; 6. Injection pipe; 7. Injection airbag; 8. Coordinating rubber sleeve; 9. Piston block; 10. Electromagnetic assembly; 101. Arc-shaped air outlet; 102. Through air passage; 103. Separated air passage; 501. First air slot; 11. Second air slot; 12. Pressure-sensing piston assembly; 13. Auxiliary pipe. Detailed Implementation

[0019] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] Example 1: Without considering the blade structure and installation strength, higher blade rotation speed can generate higher wind speeds, but airflow disturbances and other issues can also exacerbate noise generation. This invention proposes an optimization scheme to address the relationship between noise levels and blade rotation speed: Reference Figures 1-6The air volume retention type silencer based on the axial flow fan in this embodiment includes an outer shell 1, a transmission main shaft 3 and turbine blades 4. One end of the outer shell 1 is set as an arc-shaped air outlet 101, and a non-horizontal air passage is formed inside the outer shell 1 through the arc-shaped air outlet 101. An arc-shaped baffle 2 is installed inside the outer shell 1 corresponding to the arc-shaped air outlet 101. The non-horizontal air passage at the arc-shaped air outlet 101 is formed by the arc-shaped baffle 2 to form a through air passage 102 and a separation air passage 103. The arc-shaped baffle 2 is equipped with a horizontally arranged air injection pipe 6 and a semi-ventilation pipe 5 along the top to bottom direction. An airflow sensor is provided on the outer wall of the arc-shaped baffle 2 near the turbine blade 4. The position of the airflow sensor corresponds to the air injection pipe 6 and the semi-ventilation pipe 5.

[0021] Basic principle explanation: After the axial flow fan starts (powered by the motor), the motor drives the transmission main shaft 3 to rotate at high speed, which in turn drives the turbine blades 4 installed at one end of the main shaft to rotate synchronously. The structure of the turbine blades 4 must conform to the aerodynamic principle. Its rotation process is like a propeller pushing gas, so that the air forms a continuous airflow along the direction of the fan axis. The airflow enters the interior of the outer casing 1 from the air inlet of the fan. Under the driving force of the turbine blades 4, it flows along the air passage inside the casing to the arc-shaped air outlet 101, realizing the gas conveying function. It should be further explained that, without considering the installation stability of the overall structure, the structural strength / characteristics of the blades, etc., the airflow state during operation is directly related to the blade rotation speed: the higher the blade rotation speed, the greater the thrust on the air, the faster the airflow speed, and the greater the exhaust volume of the fan. However, at the same time, the high-speed rotating blades will cut the air, causing the airflow to form vortices on the blade surface and edges. In addition, when the airflow flows in the air duct, it will rub against the inner wall of the casing and the blade surface, which will further aggravate the airflow turbulence. These factors work together to produce the main noise during the operation of the axial flow fan. The noise decibels are positively correlated with the blade rotation speed, that is, the higher the rotation speed and the greater the airflow, the more prominent the noise problem. In this regard, the present invention mainly improves the sound-absorbing structure, which is essentially to change the airflow direction. Auxiliary structures such as sound insulation cotton can also be added at the air outlet. However, the key content of the present invention lies in the sound-absorbing method introduced in Embodiments 2 and 3. Its basic principle is to achieve the dual goals of noise reduction and air volume preservation by optimizing the air duct structure. One end of the outer shell 1 is set as an arc-shaped air outlet 101, so that a non-horizontal air duct is formed inside the shell. At the same time, an arc-shaped baffle 2 is installed inside the arc-shaped air outlet 101 to divide the non-horizontal air duct into a through air duct 102 and a separate air duct 103. Its essence is to reduce the degree of airflow "collision".

[0022] Example 2: Based on the technical principles proposed in Example 1, the influence of the arc-shaped baffle on airflow is first explained: The transmission main shaft 3 is arranged horizontally and passes through the arc-shaped partition 2, and the transmission main shaft 3 and the arc-shaped partition 2 are rotatably connected. The turbine blade 4 is installed at one end of the transmission main shaft 3. The cross-section of the arc-shaped partition 2 is curved to the left along the direction close to the arc-shaped air outlet 101.

[0023] Solution Description: The key component of this embodiment lies in the arc-shaped partition 2. One end of the outer casing 1 is configured as an arc-shaped air outlet 101, creating a non-horizontal air passage within the casing. Simultaneously, the arc-shaped partition 2 is installed inside the arc-shaped air outlet 101, dividing the non-horizontal air passage into a through air passage 102 and a partition air passage 103. The through air passage 102 is a continuously connected main airflow channel, maintaining unobstructed flow throughout to ensure stable and efficient airflow from the inlet to the outlet, serving as the fundamental channel for guaranteeing the fan's exhaust volume. The partition air passage 103 is a non-through auxiliary adjustment channel. Under normal conditions, it is in a closed state, and airflow is only allowed to enter when the semi-ventilation pipe 5 is opened. This avoids the main airflow being diverted and affecting the air volume under normal conditions. The air injection pipe 6 and the semi-ventilation pipe 5 installed on the arc-shaped partition 2 work together with the airflow sensor. The airflow sensor monitors the airflow speed, pressure and disturbance status in the through airway 102 in real time. When it detects that the airflow turbulence is intensifying and the noise is about to increase, it triggers the semi-ventilation pipe 5 to open, guiding part of the airflow into the separation airway 103 for adjustment, suppressing noise generation from the source, and achieving the synergy of "maintaining air volume" and "precise noise reduction". In addition to the above, the following points are added: The transmission main shaft 3 passes through the arc-shaped partition 2 horizontally, and the two remain rotatably connected. This ensures that when the transmission main shaft 3 drives the turbine blades 4 to rotate, it is not subject to mechanical interference from the arc-shaped partition 2, thus guaranteeing the smooth operation of the main shaft. The cross-section of the arc-shaped partition 2 is curved to the left along the direction close to the arc-shaped air outlet 101. This structure is adapted to the contour of the arc-shaped air outlet 101. Its function is to define the boundary between the through air passage 102 and the partition air passage 103, while optimizing the airflow path of the through air passage 102. Under normal conditions, the partition air passage 103 is in a closed state due to the closure of the semi-ventilation pipe 5, and the airflow only flows along the through air passage 102. The airflow in the air passage 102 is smoothed by the curvature of the arc-shaped baffle 2, which makes the inner wall of the air passage 102 a smooth curve. When the airflow flows in it, it can move smoothly along the wall surface, avoiding sudden turning or impact. This reduces the impact and friction between the airflow and the baffle wall, thus achieving the purpose of initial noise reduction by reducing impact. When the airflow sensor detects that the airflow disturbance in the air passage 102 is aggravated, the semi-ventilation tube 5 is opened, and part of the airflow enters the separation air passage 103 from the air passage 102. At this time, the curvature of the arc-shaped baffle can also guide the airflow in the separation air passage 103 to flow smoothly, avoiding the split airflow from becoming turbulent again. It is understandable that the left-curved arc-shaped baffle 2 creates a smooth airflow channel for the through air duct 102, guiding the main airflow to flow smoothly along the curve, avoiding turbulence or collisions in the airflow within the air duct, reducing the formation of vortices behind the blades from the root, and reducing vortex noise. The arc-shaped baffle 2 divides the main airflow channel (through air duct 102) and the auxiliary regulating channel (separation air duct 103). Under normal conditions, the separation air duct 103 is closed, and the main airflow channel is not disturbed, ensuring that the exhaust volume is stable when the blade speed remains unchanged, thus achieving the basic requirement of "maintaining air volume". When the separation air duct 103 is activated, the curved structure of the arc-shaped baffle 2 can guide the diverted airflow to flow smoothly, avoiding collisions between the diverted airflow and the main airflow at the air outlet, further reducing airflow disturbance noise.

[0024] Example 3: In conjunction with the initial airflow interference process in Example 2, the following "active interference" method is proposed for the overall airflow: An auxiliary pipe 13 is horizontally arranged along the center point of the transmission main shaft 3. One end of the auxiliary pipe 13 extends through to one end of the transmission main shaft 3 and is equipped with an auxiliary impeller. A second air groove 11 is formed on the outer wall of the transmission main shaft 3 corresponding to the position in the partition air passage 103. A pressure-sensing piston assembly 12 corresponding to the second air groove 11 is arranged between the inside of the transmission main shaft 3 and the other end of the auxiliary pipe 13. The air injection pipe 6 and the semi-ventilation pipe 5 are at different heights in the vertical direction, and the ends of the air injection pipe 6 and the semi-ventilation pipe 5 corresponding to the ends of the air passage 102 are open. The air inlet tube 6 is shaped like an inlet. On the outer wall of the partition airway 103, an air inlet bladder 7 and a cooperating rubber sleeve 8 are respectively provided. The cooperating rubber sleeve 8 is symmetrically arranged along the position of the air inlet bladder 7. The air inlet bladder 7 and the air inlet tube 6 are in a communication state. A ball head connector is provided at the intersection of the cooperating rubber sleeve 8 and the air inlet tube 6. A first air groove 501 is provided on the outer wall of the partition airway 103. An energized electromagnetic component 10 and a piston block 9 are respectively provided on both sides of the first air groove 501 inside the semi-ventilation tube 5.

[0025] Solution Description: The overall process includes the following stages: S1: The semi-ventilation tube 5 is at a different height from the air injection tube 6 in the vertical direction. One end of it, corresponding to the through-passage duct 102, is open. A first air groove 501 is formed on the outer wall of the corresponding partition duct 103. An energized electromagnetic component 10 and a piston block 9 are arranged on both sides of the first air groove 501. When the airflow sensor detects that the airflow disturbance in the through-passage duct 102 is aggravated (the noise is about to increase), it will transmit an electrical signal to the energized electromagnetic component 10, which will be energized to generate a magnetic force. The magnetic force attracts the piston block 9 along the semi-ventilation tube 5. Axial movement opens the first air slot 501. At this time, part of the airflow in the through airway 102 enters the pipe through the opening end of the semi-ventilation pipe 5, and then flows into the dividing airway 103 through the first air slot 501, completing the diversion action. When the airflow returns to stability, the energized electromagnetic component 10 is de-energized, the magnetic force disappears, the piston block 9 resets and closes the first air slot 501, the dividing airway 103 returns to the closed state, and the airflow only flows along the through airway 102. This stage is a simple active interference process, which is essentially an airflow diversion process. S2: The inflation tube 6 is always connected to the through airway 102. When the semi-ventilation tube 5 is opened and the airflow enters the partition airway 103, the inflation tube 6 introduces part of the main airflow through the opening end of the through airway 102 to inflate the inflation bladder 7. After the inflation bladder 7 expands, the cooperating rubber sleeves 8 on both sides become movable under the action of the ball joint connector, and there is an airflow state in the partition airway 3. The ball joint connector pushes the cooperating rubber sleeves 8 on both sides to move synchronously or asynchronously, forming a curved structure that adapts to the split airflow. The structure can guide the split airflow in the dividing airway 103 to flow in a preset direction, so that the split airflow can be smoothly superimposed with the main airflow in the through airway 102 at the air outlet, avoiding the collision of the two airflows due to the difference in flow direction and flow rate, and suppressing disturbance noise. Secondly, the rubber sleeve 8 can also collide with the inflatable airbag 7. Since both are made of rubber, they will not make obvious noise even if they collide. The purpose is to "consume" the kinetic energy of the airflow by consuming kinetic energy, which also avoids the collision of the two airflows due to the difference in flow direction and flow rate, suppresses disturbance noise, and ensures stable airflow. S3: This section is supplementary to the overall solution: If only the air passage 102 maintains the airflow direction and the transmission shaft 3 maintains a uniform rotation speed, the resulting wind speed is relatively stable. Therefore, under the influence of this wind speed, the auxiliary passage 13 will also rotate in a directional manner. The pressure-sensing piston assembly 12 is essentially a physical pressure-sensing method composed of a piston structure and a spring. When the wind speed is relatively stable, some airflow will also be injected into the transmission shaft 3 through the auxiliary passage 13, generating leftward pressure on its piston structure. However, referring to... Figure 5This can be understood as follows: the greater the wind speed, the greater the leftward pressure generated. Therefore, in the initial state, the piston structure completely blocks the first air groove 501 under the elastic potential energy of the spring. However, under the action of the leftward pressure, the piston structure moves to the left, which may open the first air groove 501. Thus, the piston structure resets under the action of elastic potential energy. This can be further understood as follows: if the airflow pressure in the dividing air passage 103 is abnormal (the diverted airflow is violently disturbed), the feeding structure in the pressure-sensing piston assembly 12 moves axially along the auxiliary passage 13 under the action of pressure, adjusting the airflow flow of the auxiliary passage 13, and then fine-tuning the airflow speed in the dividing air passage 103, so that the flow rate of the diverted airflow and the main airflow tend to match, further suppressing airflow turbulence. This part belongs to the mechanical passive adjustment method, which is only a fine-tuning action and does not affect the airflow volume. It mainly stabilizes the airflow.

[0026] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to specific implementations. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A volume-retaining silencer based on an axial flow fan, comprising a housing (1), a drive shaft (3), and turbine blades (4), characterized in that, One end of the outer shell (1) is set as an arc-shaped air outlet (101), and a non-horizontal air passage is formed inside the outer shell (1) through the arc-shaped air outlet (101). An arc-shaped partition (2) is installed inside the outer shell (1) corresponding to the arc-shaped air outlet (101). The non-horizontal air passage corresponding to the arc-shaped air outlet (101) is formed by the arc-shaped baffle (2) to form a through air passage (102) and a separation air passage (103). The arc-shaped baffle (2) is equipped with a horizontally arranged air injection pipe (6) and a semi-ventilation pipe (5) respectively from top to bottom. An airflow sensor is provided on the outer wall of the arc-shaped baffle (2) near the turbine blade (4). The position of the airflow sensor corresponds to the air injection pipe (6) and the semi-ventilation pipe (5).

2. The air volume retention type silencer based on an axial flow fan according to claim 1, characterized in that, The transmission main shaft (3) is arranged in the horizontal direction and passes through the arc-shaped partition (2), and the transmission main shaft (3) and the arc-shaped partition (2) are rotatably connected. The turbine blade (4) is installed at one end of the transmission main shaft (3).

3. The air volume retention type silencer based on an axial flow fan according to claim 1, characterized in that, The cross-section of the arc-shaped partition (2) is curved to the left along the direction close to the arc-shaped air outlet (101).

4. The air volume retention type silencer based on an axial flow fan according to claim 1, characterized in that, An auxiliary pipe (13) is arranged horizontally along the center point of the transmission main shaft (3). One end of the auxiliary pipe (13) extends through to one end of the transmission main shaft (3) and is equipped with an auxiliary impeller. A second air groove (11) is opened on the outer wall of the transmission main shaft (3) corresponding to the position of the partition air passage (103).

5. The air volume retention type silencer based on an axial flow fan according to claim 4, characterized in that, A pressure-sensing piston assembly (12) corresponding to the second air groove (11) is provided between the inside of the transmission main shaft (3) and the other end of the auxiliary passage pipe (13).

6. The air volume retention type silencer based on an axial flow fan according to claim 1, characterized in that, The air injection pipe (6) and the semi-ventilation pipe (5) are positioned at different heights along the vertical direction, and the ends of the air injection pipe (6) and the semi-ventilation pipe (5) corresponding to the through airway (102) are open.

7. The air volume retention type silencer based on an axial flow fan according to claim 6, characterized in that, The air injection tube (6) is provided with an air injection bladder (7) and a cooperating rubber sleeve (8) on the outer wall of the partition airway (103), respectively. The cooperating rubber sleeve (8) is symmetrically arranged along the position of the air injection bladder (7).

8. The air volume retention type silencer based on an axial flow fan according to claim 7, characterized in that, The air-filled bladder (7) and the air-filled tube (6) are in a state of communication. A ball-head connector is provided at the intersection of the cooperating rubber sleeve (8) and the air-filled tube (6).

9. The air volume retention type silencer based on an axial flow fan according to claim 6, characterized in that, The semi-ventilated pipe (5) is provided with a first air groove (501) on the outer wall of the partition airway (103), and an energized electromagnetic component (10) and a piston block (9) are respectively provided on both sides of the first air groove (501) inside the semi-ventilated pipe (5).

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