Noise improvement device for a device air flow passage

Abstract

The utility model relates to noise reduction technical field discloses the noise improvement device suitable for equipment airflow channel, installs on the airflow channel of equipment original, including air inlet pipe, air outlet pipe, communication pipe, baffle and the first expansion chamber and second expansion chamber of series connection setting, the baffle separates the first expansion chamber and second expansion chamber, the air inlet pipe is linked with the first expansion chamber, the communication pipe passes through the baffle and the both ends of communication pipe are linked with the first expansion chamber and second expansion chamber respectively, the air outlet pipe is linked with the second expansion chamber. The utility model discloses two series connection design expansion chambers on the airflow channel of noise generating equipment, and the airflow with noise is reflected many times in the process of passing through two expansion chambers from the sound source, and the reflected sound wave and the sound wave of the noise of subsequent entering the expansion chamber interfere with each other, thereby reaches the effect of noise reduction.

Description

Technical Field

[0001] This utility model relates to the field of noise reduction technology, and in particular to a noise improvement device suitable for the airflow channel of equipment. Background Technology

[0002] In modern industrial production systems, the production workshop, as a core operational environment, directly impacts employee occupational health and corporate sustainable development. However, in specific production stages in industries such as food processing and machinery manufacturing, the high-frequency, high-amplitude noise generated by equipment operation is particularly prominent. During equipment operation, the combined effects of mechanical transmission friction, component vibration, and airflow disturbances result in noise levels far exceeding national standard limits. Prolonged exposure to such high-noise environments can cause multiple harms to employees' physical and mental health, indirectly leading to a 15%-20% reduction in production efficiency, while also increasing the risk of safety accidents caused by operational errors.

[0003] For automated belt conveyor systems used in the sterilization process of soft-bag pharmaceutical production, the noise generated is the result of a coupling effect of metal impact, structural vibration, and airflow disturbance. Some traditional noise reduction methods are only effective for low- to mid-frequency noise caused by vibration. For high-frequency noise (1000Hz-4000Hz) generated by airflow disturbance and metal impact during the operation of automated belt conveyor systems, the noise reduction effect is less than 5 dB. Sound insulation materials (such as rock wool) only reduce the sound of high-frequency noise by 15-20 dB, and noise reflection is easily formed inside the sound insulation cover, leading to local noise superposition.

[0004] Therefore, it is necessary to design a noise reduction device that targets the airflow noise characteristics of equipment and can effectively improve high-frequency noise. Utility Model Content

[0005] To address the problems existing in the prior art, where current noise reduction methods are ineffective in dealing with high-frequency noise generated by airflow disturbances, the purpose of this invention is to provide a noise reduction device suitable for the airflow channel of equipment. By setting two series-connected expansion chambers in the airflow channel of the noise-generating equipment, the sound waves are reflected multiple times as the noisy airflow passes through the two expansion chambers from the sound source. The reflected sound waves interfere with the noise sound waves that subsequently enter the expansion chambers, thereby achieving a noise reduction effect.

[0006] To achieve the above objectives, the technical solution of this utility model is as follows: A noise reduction device suitable for the airflow channel of equipment is installed on the original airflow channel of the equipment. It includes an inlet pipe, an outlet pipe, a connecting pipe, a partition, and a first expansion chamber and a second expansion chamber arranged in series. The partition separates the first expansion chamber and the second expansion chamber. The inlet pipe is connected to the first expansion chamber. The connecting pipe passes through the partition and its two ends are connected to the first expansion chamber and the second expansion chamber, respectively. The outlet pipe is connected to the second expansion chamber.

[0007] The present invention is further configured such that the volume of the first expansion chamber is smaller than the volume of the second expansion chamber.

[0008] The present invention is further configured such that the length of the connecting pipe in the first expansion chamber is less than the length of the connecting pipe in the second expansion chamber.

[0009] The present invention is further configured such that both the first expansion chamber and the second expansion chamber are cylindrical.

[0010] The present invention is further configured such that the air inlet pipe, air outlet pipe, connecting pipe, partition, first expansion chamber and second expansion chamber are all made of stainless steel.

[0011] The present invention is further configured such that: the cross-sectional area of ​​the air inlet pipe in the direction perpendicular to its own length is smaller than the cross-sectional area of ​​the first expansion chamber, and the cross-sectional area of ​​the air outlet pipe in the direction perpendicular to its own length is smaller than the cross-sectional area of ​​the second expansion chamber.

[0012] The present invention is further configured such that the depth of the air inlet pipe inserted into the first expansion chamber is adjustable, and the depth of the air outlet pipe inserted into the second expansion chamber is adjustable.

[0013] The present invention is further configured such that the central axes of the air inlet pipe and the air outlet pipe do not coincide with the central axis of the connecting pipe.

[0014] The present invention is further configured such that the connecting tube is spindle-shaped.

[0015] The present invention is further configured such that the opening of the connecting pipe in the first expansion chamber is in the shape of a flared mouth, and the opening diameter of the connecting pipe in the first expansion chamber is larger than the opening diameter of the connecting pipe in the second expansion chamber.

[0016] In summary, the beneficial effects achieved by this utility model are as follows: (1) This device is directly installed in the original airflow channel of the equipment, and only suppresses the aerodynamic noise source. It does not interfere with the original airflow channel structure and heat dissipation efficiency, and does not change the original structure and layout of the equipment. While achieving the noise reduction function, it does not affect the normal operation and maintenance of the equipment. It has the characteristics of convenient installation, no occupation of operating space, and low maintenance cost. (2) The noisy airflow goes from the inlet pipe to the first expansion chamber, from the first expansion chamber to the connecting pipe, from the connecting pipe to the second expansion chamber, and from the second expansion chamber to the outlet pipe. The airflow direction is changed repeatedly, and the repeated cross-sectional changes on the flow path are superimposed, which induces the sound waves to reflect continuously and generate interference. The interference cancels each other out, thereby achieving the suppression of aerodynamic noise. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the specification will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this utility model. For those skilled in the art, other drawings can be obtained based on these drawings.

[0018] Figure 1 This is a schematic diagram of the noise reduction device applicable to the airflow channel of the equipment in this utility model; Figure 2 This is a schematic diagram of the flow path in the noise reduction device applicable to the airflow channel of the equipment in this utility model, which is used for airflow with noise.

[0019] In the diagram: 1. Inlet pipe; 2. First expansion chamber; 3. Baffle; 4. Connecting pipe; 41. Collection port; 42. Reflection chamber; 5. Second expansion chamber; 6. Outlet pipe. Detailed Implementation

[0020] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, not all embodiments. For ease of explanation, the terms "vertical", "horizontal", "left", "right", "upper", "lower", "inner", "outer", "bottom", etc., used in this specification to indicate the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0021] Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0022] As attached Figure 1-2 As shown, this is a noise reduction device suitable for the airflow channel of equipment, installed on the original airflow channel of equipment that has an airflow channel and generates noise. The device includes an inlet pipe 1, an outlet pipe 6, a connecting pipe 4, a partition 3, and a first expansion chamber 2 and a second expansion chamber 5 arranged in series.

[0023] The first expansion chamber 2 and the second expansion chamber 5 are both cylindrical cavity structures. The partition 3 is a circular flat plate structure, which is located between the first expansion chamber 2 and the second expansion chamber 5, thereby separating the first expansion chamber 2 and the second expansion chamber 5.

[0024] In the direction perpendicular to the axis of the first expansion chamber 2 and the second expansion chamber 5, the cross-sectional areas of the two are equal, and the volume of the first expansion chamber 2 is smaller than the volume of the second expansion chamber 5.

[0025] The intake pipe 1 is inserted into and communicates with the first expansion chamber 2, thereby introducing noisy gas into the first expansion chamber 2. The length direction of the intake pipe 1 is parallel to the axial direction of the first expansion chamber 2, and the cross-sectional area of ​​the intake pipe 1 perpendicular to its own length direction is smaller than the cross-sectional area of ​​the first expansion chamber 2.

[0026] The connecting pipe 4 passes through the partition 3, and its two ends are connected to the first expansion chamber 2 and the second expansion chamber 5, respectively. The central axis of the connecting pipe 4 is parallel to but does not coincide with the axis of the intake pipe 1. In this embodiment, the axis of the intake pipe 1 is located at the upper part of the first expansion chamber 2, while the central axis of the connecting pipe 4 is located at the lower part of the first expansion chamber 2.

[0027] The connecting pipe 4 is provided with a collection port 41 with a funnel-shaped opening inside the first expansion chamber 2, and the larger diameter end of the collection port 41 faces the first expansion chamber 2, so that airflow and sound waves can enter the connecting pipe 4 from the collection port 41.

[0028] The connecting pipe 4 is generally spindle-shaped, and its length within the second expansion chamber 5 is greater than its length within the first expansion chamber 2. A spindle-shaped reflecting cavity 42 is located in the middle of the connecting pipe 4, and the diameter of the reflecting cavity 42 is greater than the maximum diameter of the collecting port 41. The diameter of the outlet of the connecting pipe 4 within the second expansion chamber 5 is smaller than the minimum diameter of the collecting port 41.

[0029] The exhaust pipe 6 is inserted into and connected to the second expansion chamber 5. The length direction of the exhaust pipe 6 is parallel to the axial direction of the intake pipe 1, and the cross-sectional area of ​​the exhaust pipe 6 perpendicular to its own length direction is smaller than the cross-sectional area of ​​the second expansion chamber 5.

[0030] The axis of the vent pipe 6 is parallel to but does not coincide with the axis of the connecting pipe 4. In this embodiment, the axis of the vent pipe 6 is located at the upper part of the second expansion chamber 5, while the central axis of the connecting pipe 4 is located at the lower part of the second expansion chamber 5.

[0031] In this invention, the air inlet pipe 1, air outlet pipe 6, connecting pipe 4, partition 3, first expansion chamber 2 and second expansion chamber 5 are all made of corrosion-resistant stainless steel and the surface is passivated, thereby ensuring that the entire device has long-term durability, airtightness and stability in a high temperature (>80 degrees) and high humidity sterilization environment.

[0032] In some other embodiments, the depth to which the intake pipe 1 is inserted into the first expansion chamber 2 and the depth to which the exhaust pipe 6 is inserted into the second expansion chamber 5 are both adjustable, thereby adjusting the effect of sound wave interference in the first expansion chamber 2 and the second expansion chamber 5 by adjusting the insertion depth of the intake pipe 1 and the exhaust pipe 6.

[0033] The implementation principle of the above embodiments is as follows: This device can be directly installed on the existing airflow channel of the noisy equipment via the inlet pipe 1 and the outlet pipe 6. The moment the noisy airflow enters the first expansion chamber 2 through the inlet pipe 1, the cross-section of the gas flow channel suddenly expands (acoustic impedance change), causing the sound waves to spread outwards. Upon contact with the inner wall of the first expansion chamber 2, the sound waves are reflected back towards the sound source, interfering with the diffused sound waves. Specifically, the part directly opposite the inlet pipe 1 is not the collection port 41 of the connecting pipe 4, but the baffle 3. The sound waves reflected by the baffle 3 directly interfere with the sound waves in the inlet pipe 1, partially canceling out the sound waves. The airflow in the first expansion chamber 2, along with the noise sound waves, enters the connecting pipe 4 through the collection port 41. The cross-section of the gas flow channel suddenly shrinks (acoustic impedance change), causing the sound waves to concentrate inwards. During the flow, they are continuously reflected, diffuse and interfere with each other in the reflection cavity 42 in the middle of the connecting pipe 4, and then enter the second expansion chamber 5 through the outlet of the connecting pipe 4. The cross-section of the gas flow channel suddenly expands again, resulting in even greater reflection and interference in the second expansion chamber 5, until it is discharged from the outlet pipe 6. At this time, the noise waves in the airflow are constantly reflected and interfere with each other to cancel each other out, thereby suppressing aerodynamic noise and effectively reducing the noise level.

[0034] Although preferred embodiments of the present invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the present invention. Clearly, those skilled in the art can make various alterations and modifications to the present invention without departing from its spirit and scope. Thus, if such modifications and modifications fall within the scope of the claims of the present invention and their equivalents, the present invention also intends to include such modifications and modifications.

Claims

1. A noise reduction device suitable for airflow channels in equipment, characterized in that, Installed on the original airflow channel of the equipment, it includes an inlet pipe (1), an outlet pipe (6), a connecting pipe (4), a partition (3), and a first expansion chamber (2) and a second expansion chamber (5) arranged in series. The partition (3) separates the first expansion chamber (2) and the second expansion chamber (5). The inlet pipe (1) is connected to the first expansion chamber (2). The connecting pipe (4) passes through the partition (3) and its two ends are connected to the first expansion chamber (2) and the second expansion chamber (5) respectively. The outlet pipe (6) is connected to the second expansion chamber (5).

2. The noise reduction device for equipment airflow channels according to claim 1, characterized in that, The volume of the first expansion chamber (2) is smaller than the volume of the second expansion chamber (5).

3. The noise reduction device for equipment airflow channels according to claim 2, characterized in that, The length of the connecting pipe (4) in the first expansion chamber (2) is less than the length of the connecting pipe (4) in the second expansion chamber (5).

4. The noise reduction device for equipment airflow channels according to claim 1, characterized in that, Both the first expansion chamber (2) and the second expansion chamber (5) are cylindrical.

5. The noise reduction device for equipment airflow channels according to claim 1, characterized in that, The air inlet pipe (1), air outlet pipe (6), connecting pipe (4), partition (3), first expansion chamber (2) and second expansion chamber (5) are all made of stainless steel.

6. The noise reduction device for equipment airflow channels according to claim 1, characterized in that, The cross-sectional area of ​​the air inlet pipe (1) perpendicular to its own length direction is smaller than the cross-sectional area of ​​the first expansion chamber (2), and the cross-sectional area of ​​the air outlet pipe (6) perpendicular to its own length direction is smaller than the cross-sectional area of ​​the second expansion chamber (5).

7. The noise reduction device for equipment airflow channels according to claim 1, characterized in that, The depth to which the air inlet pipe (1) is inserted into the first expansion chamber (2) is adjustable, and the depth to which the air outlet pipe (6) is inserted into the second expansion chamber (5) is adjustable.

8. The noise reduction device for equipment airflow channels according to claim 1, characterized in that, The central axes of the air inlet pipe (1) and the air outlet pipe (6) do not coincide with the central axis of the connecting pipe (4).

9. The noise reduction device for equipment airflow channels according to claim 1, characterized in that, The connecting tube (4) is spindle-shaped.

10. The noise reduction device for equipment airflow channels according to claim 9, characterized in that, The opening of the connecting pipe (4) in the first expansion chamber (2) is in the shape of a trumpet, and the diameter of the opening of the connecting pipe (4) in the first expansion chamber (2) is greater than the diameter of the opening of the connecting pipe (4) in the second expansion chamber (5).

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