A noise reduction device for a nitrogen generator
By using helical blades and a multi-stage resonant cavity structure in the nitrogen generator exhaust port silencer, the problem of limited gas flow time was solved, achieving efficient noise reduction and cost control, adapting to various working conditions, and improving the versatility and stability of the device.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- GUANGZHOU KELI COMPRESSED AIR SYST ENG CO LTD
- Filing Date
- 2025-06-17
- Publication Date
- 2026-06-16
AI Technical Summary
Existing nitrogen generator exhaust silencers have limited gas flow time, resulting in poor noise reduction effect and high production cost.
By employing a helical blade and multi-stage resonant cavity structure, the gas flow path is adjusted through the helical blade, and the reflection and interference of the multi-stage resonant cavity are combined to extend the residence time of the gas in the silencer. The airflow is released in stages through the vent holes to achieve multi-stage noise reduction.
It significantly improves noise reduction within a limited space, reduces production costs, enhances the adaptability and durability of the device, enables it to adapt to different working conditions, and reduces the complexity of equipment maintenance and upgrades.
Smart Images
Figure CN224366549U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of nitrogen generator silencers, specifically a nitrogen generator noise reduction device. Background Technology
[0002] Nitrogen generator exhaust silencers are mainly used to reduce the noise of high-pressure gas generated during the exhaust process of nitrogen generators and improve the working environment. Common silencer types include resistive silencers, reactive silencers, and resistive-reactive composite silencers.
[0003] Existing silencers utilize multiple resonant cavities to effectively reduce noise at the nitrogen generator's exhaust port. However, a problem exists in practical use: the time it takes for the discharged high-pressure gas to pass through the silencer's pipe is related to the pipe's length and the gas flow rate. To increase the gas's transit time within the silencer and improve the silencing effect, the traditional approach is to lengthen the silencer pipe, customizing it to meet specific needs. This undoubtedly increases manufacturing and design costs. Therefore, the inventors urgently need to design an adjustment mechanism that can regulate the gas's flow time within the silencer pipe, thereby improving the silencer's environmental adaptability. Summary of the Invention
[0004] Based on this, the purpose of this utility model is to provide a noise reduction device for a nitrogen generator, so as to solve the technical problem of limited gas flow time inside the silencer pipe of the nitrogen generator exhaust port silencer.
[0005] To achieve the above objectives, this utility model provides the following technical solution: a noise reduction device for a nitrogen generator, comprising a silencer body, wherein a main silencer pipe and a secondary silencer pipe are provided inside the silencer body, a spiral blade is movably installed on the inner side of the main silencer pipe, the spiral blade is adapted to the main silencer pipe, an exhaust pipe is connected to the outer flange of the main silencer pipe, a gasket is provided at the end of the spiral blade near the exhaust pipe, and the connecting flange of the exhaust pipe presses against the gasket and the spiral blade.
[0006] By adopting the above technical solution, a spiral blade is movably installed inside the main silencer pipe, and combined with the flange-connected exhaust pipe and the pressure fixing structure of the gasket ring, the gas flow path can be dynamically adjusted within a limited space. The spiral blade forces the gas to form a swirling flow through its spiral shape, prolonging the residence time of the gas in the main silencer pipe, thereby enhancing the reduction of high-frequency noise.
[0007] Furthermore, the spiral blades are available in two, but not limited to, specifications to adapt to various usage environments.
[0008] By adopting the above technical solutions, the various specifications of the helical blades provide flexible adaptability to different operating conditions. For example, in high-flow-rate environments, helical blades with smaller blade spacing can be used to increase airflow resistance and extend the noise reduction path; while in low-flow-rate operating conditions, blades with larger spacing can be used to reduce pressure loss.
[0009] Furthermore, the internal cavity of the muffler body is divided into multiple resonant cavities by a first partition, a second partition, and a third partition.
[0010] By adopting the above technical solutions, multi-level reflection and interference of sound waves can be achieved. Resonant cavities of different sizes can attenuate noise of specific frequencies. For example, low-frequency noise is effectively absorbed in larger cavities due to wavelength matching, while medium and small cavities can suppress medium and high-frequency noise.
[0011] Furthermore, the main silencer tube and the auxiliary silencer tube are provided with several vent holes at equal intervals on their surfaces, which are connected to multiple external resonant cavities.
[0012] By adopting the above technical solution, the vent holes equidistantly opened on the surface of the main silencer pipe and the auxiliary silencer pipe promote the gas to enter the resonant cavity in stages through the uniform distribution of airflow inlets and outlets, avoiding eddy noise caused by local airflow concentration. At the same time, the impact intensity of airflow is reduced by releasing small flow rates multiple times. After the vent holes are connected to the resonant cavity, sound waves can penetrate the holes and enter the cavity, thereby achieving noise reduction through reflection cancellation and energy dissipation.
[0013] Furthermore, the main silencer pipe passes through the first partition and the second partition, and the auxiliary silencer pipe passes through the second partition and the third partition.
[0014] By adopting the above technical solution, the gas forms a multi-stage pressure reduction effect when flowing through different baffles. The first baffle in the front section of the main silencer pipe achieves initial noise reduction, and the second baffle further buffers the flow. The diversion of the auxiliary silencer pipe reduces the remaining noise through two-stage baffles.
[0015] Furthermore, the surface of the second partition is provided with flow holes for gas flow.
[0016] By adopting the above technical solution, the flow hole on the surface of the second partition plate balances the air pressure between adjacent resonant cavities, preventing gas from accumulating due to pressure difference and causing instantaneous impact noise. The hole allows a small amount of gas to flow slowly between the cavities, which maintains the independence of multi-cavity silencing and promotes the flexible release of sound wave energy through micro-airflow exchange.
[0017] Furthermore, the surface of the spiral blade is provided with several through holes.
[0018] By adopting the above technical solution, the through holes on the surface of the spiral blades generate local disturbances to the airflow, breaking the original continuous flow state and forcing the gas to form micro-turbulence when passing through the through holes, thereby accelerating the conversion of sound energy into heat energy. The combination of the through holes and the spiral path makes the airflow exhibit segmented acceleration and deceleration, further extending the effective noise reduction time.
[0019] In summary, the present invention has the following main advantages:
[0020] This invention utilizes spiral blades to allow high-pressure gas to enter the main silencer body and preferentially flow into the main silencer pipe. The airflow resistance and direction are actively controlled through the through holes on the surface of the spiral blades, forcing the airflow to disperse through the holes and move along the spiral path. This extends the gas flow path and residence time at the same flow rate, thereby enhancing the sound energy attenuation efficiency. The spiral blades are pressed and fixed by the exhaust pipe flange to ensure their positional stability and avoid displacement or vibration caused by airflow impact. Attached Figure Description
[0021] Figure 1 This is a three-dimensional structural diagram of the present invention;
[0022] Figure 2 This is a cross-sectional internal structure diagram of the present invention;
[0023] Figure 3 This is a schematic diagram of the internal structure of the present invention;
[0024] Figure 4 This utility model Figure 2 Enlarged structural diagram at point A;
[0025] Figure 5 This is a schematic diagram of another embodiment of the present invention.
[0026] In the diagram: 1. Muffler body; 2. Main muffler pipe; 3. Secondary muffler pipe; 401. First baffle; 402. Second baffle; 403. Third baffle; 404. Flow hole; 5. Spiral blade; 6. Gasket ring; 7. Exhaust pipe; 8. Through hole. Detailed Implementation
[0027] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention. Example
[0028] A noise reduction device for a nitrogen generator, such as Figure 1-5As shown, the muffler includes a main body 1, inside which are a main muffler pipe 2 and a secondary muffler pipe 3. A spiral blade 5 is movably mounted on the inner side of the main muffler pipe 2, and the spiral blade 5 is adapted to the main muffler pipe 2. An exhaust pipe 7 is connected to the outer flange of the main muffler pipe 2. A gasket 6 is provided at the end of the spiral blade 5 near the exhaust pipe 7. The connecting flange of the exhaust pipe 7 presses against the gasket 6 and the spiral blade 5. The spiral blade 5 is movably mounted inside the main muffler pipe 2, and combined with the flange-connected exhaust pipe 7 and the gasket 6 pressing and fixing structure, it can... The gas flow path is dynamically adjusted within the chamber. The spiral blades 5 force the gas to form a swirling flow through their spiral shape, prolonging the residence time of the gas in the main silencer pipe 2, thereby enhancing the reduction of high-frequency noise. At the same time, the setting of the main silencer pipe 2 and the auxiliary silencer pipe 3 allows for the separate processing of high-pressure gas, avoiding excessive load on a single pipeline. Combined with the overall structure of the silencer body 1, it can balance the airflow pressure and disperse noise energy. The presence of the gasket ring 6 further ensures the stable installation of the spiral blades 5, reduces structural wear caused by vibration, and improves the durability of the device.
[0029] See Figure 1 , Figure 2 , Figure 3 The helical blades 5 come in two, but not limited to, specifications to adapt to various operating environments. The multiple specifications of the helical blades 5 provide flexible adaptability to different operating conditions. For example, in high-flow-rate environments, helical blades with smaller blade spacing can be used to increase airflow resistance and extend the silencing path; while in low-flow-rate conditions, blades with larger spacing can be used to reduce pressure loss. At the same time, the replaceable blade structure simplifies the maintenance and upgrade process of the equipment. There is no need to replace the entire silencer body 1; only the helical blades 5 need to be replaced to match new operating requirements. This significantly reduces production costs and downtime, enhances the versatility of the device, and provides technical support for the diverse application scenarios of nitrogen generators.
[0030] See Figure 2 , Figure 3 The internal cavity of the silencer body 1 is divided into multiple resonant cavities by the first partition 401, the second partition 402, and the third partition 403, which can realize multi-level reflection and interference of sound waves. The resonant cavities of different sizes are targeted attenuation for noise of specific frequencies. For example, low-frequency noise is effectively absorbed in larger cavities due to wavelength matching, while medium and small cavities can suppress medium and high-frequency noise. At the same time, the structural separation of the partitions also forms an airflow buffer layer, which prevents high-pressure gas from directly impacting the silencer wall and reduces secondary noise generated by structural vibration. The multi-cavity collaborative operation not only expands the coverage of the noise reduction band, but also reduces the pressure load of a single cavity through layered energy dissipation, ensuring long-term stable operation of the device.
[0031] See Figure 2 , Figure 3The main silencer pipe 2 and the auxiliary silencer pipe 3 have several vent holes equidistantly opened on their surfaces, which are connected to multiple external resonant cavities. The vent holes equidistantly opened on the surfaces of the main silencer pipe 2 and the auxiliary silencer pipe 3 promote the gas to enter the resonant cavity in stages by uniformly distributing the airflow inlet and outlet, avoiding eddy noise caused by local airflow concentration. At the same time, the impact intensity of the airflow is reduced by releasing small flow rates multiple times. After the vent holes are connected to the resonant cavity, the sound waves can penetrate the holes and enter the cavity. Then, noise reduction is achieved through reflection cancellation and energy dissipation. Meanwhile, the equidistantly distributed holes ensure that the gas flow on the pipe surface is balanced, preventing structural resonance caused by flow velocity differences.
[0032] See Figure 2 , Figure 3 The main silencer pipe 2 passes through the first partition 401 and the second partition 402, while the secondary silencer pipe 3 passes through the second partition 402 and the third partition 403. This creates a multi-stage pressure reduction effect as the gas flows through different partitions. The initial section of the main silencer pipe 2 achieves initial noise reduction through the first partition 401, and is further buffered by the second partition 402. The flow diversion of the secondary silencer pipe 3 reduces the remaining noise through the two-stage partitions. At the same time, the through-type structure ensures physical isolation between the resonant cavities, avoids airflow short-circuiting, and ensures that the sound waves are fully attenuated within the cavity. Through the layered and progressive silencer path, this structure maximizes the use of the multi-cavity synergistic effect within a limited space, significantly improving the comprehensive reduction capability of high and low frequency noise.
[0033] See Figure 2 , Figure 3 The surface of the second partition 402 is provided with flow holes 404 for gas flow. The flow holes 404 on the surface of the second partition 402 balance the gas pressure between adjacent resonant cavities, preventing gas from accumulating due to pressure difference and causing instantaneous impact noise. The holes allow a small amount of gas to flow slowly between the cavities, which maintains the independence of multi-cavity silencing and promotes the flexible release of sound wave energy through micro-airflow exchange. At the same time, the distribution position and aperture size of the flow holes 404 are matched and set to suppress high-frequency noise while retaining the low-frequency silencing effect. This dynamic balance mechanism not only enhances the silencing stability, but also avoids structural deformation of local cavities due to excessive pressure, ensuring the reliability of the device under long-term high-pressure conditions. Example
[0034] See Figure 5 The surface of the spiral blade 5 has several through holes 8. The through holes 8 on the surface of the spiral blade 5 generate local disturbances to the airflow, breaking the original continuous flow state and forcing the gas to form micro-turbulence when passing through the through holes, thereby accelerating the conversion of sound energy into heat energy. The combination of the through holes 8 and the spiral path makes the airflow exhibit segmented acceleration and deceleration, further extending the effective noise reduction time. At the same time, the distribution of the through holes can adjust the airflow direction, causing some gas to obliquely impact the wall of the resonant cavity, exciting multi-mode sound field interference, and enhancing the low-frequency noise reduction effect.
[0035] The implementation principle of this embodiment is as follows: After high-pressure gas enters the silencer body 1, it first flows into the main silencer pipe 2, and then into the auxiliary silencer pipe 3. The spiral blades 5 inside the main silencer pipe 2 are fixed by the clamping action of the flange connection of the exhaust pipe 7. The through holes 8 on its surface can control the resistance of the airflow through the spiral blades 5, and at the same gas flow rate, extend the gas flow path and residence time. At the same time, the spiral blades 5 can be replaced with different specifications to adapt to different flow rate conditions. The gas enters multiple resonant cavities separated by the first partition 401, the second partition 402, and the third partition 403 through the vent holes on the surface of the main silencer pipe 2 and the auxiliary silencer pipe 3. Low-frequency noise is canceled by the sound wave reflection between the cavities. The flow hole 404 of the second partition 402 promotes the gas pressure balance between the cavities, while the structure of the auxiliary silencer pipe 3 that penetrates the partition further disperses the airflow impact, realizing multi-stage buffering and noise reduction. Overall, through the dynamic turbulence of the spiral blades 5, the interference of multiple resonant cavities, and the synergistic effect of the flow-dividing structure, the gas flow time and the silencing effect are optimized without significantly extending the pipeline.
[0036] Although embodiments of the present invention have been shown and described, these specific embodiments are merely explanations of the present invention and are not intended to limit the invention. The specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. After reading this specification, those skilled in the art may make modifications, substitutions, and variations to the embodiments as needed without departing from the principles and spirit of the present invention, provided that such modifications, substitutions, and variations are within the scope of the claims of the present invention and are protected by patent law.
Claims
1. A noise reduction device for a nitrogen generator, characterized in that: The device includes a muffler body (1), inside which a main muffler pipe (2) and a secondary muffler pipe (3) are provided. A spiral blade (5) is movably installed on the inner side of the main muffler pipe (2). The spiral blade (5) is adapted to the main muffler pipe (2). An exhaust pipe (7) is connected to the outer flange of the main muffler pipe (2). A gasket (6) is provided at the end of the spiral blade (5) near the exhaust pipe (7). The connecting flange of the exhaust pipe (7) presses against the gasket (6) and the spiral blade (5).
2. The noise reduction device for a nitrogen generator according to claim 1, characterized in that: The spiral blades (5) are available in two, but not limited to, specifications to adapt to various usage environments.
3. The noise reduction device for a nitrogen generator according to claim 1, characterized in that: The internal cavity of the muffler body (1) is divided into multiple resonant cavities by the first partition (401), the second partition (402), and the third partition (403).
4. The noise reduction device for a nitrogen generator according to claim 1, characterized in that: The main silencer tube (2) and the auxiliary silencer tube (3) have several vent holes at equal intervals on their surfaces, which are connected to multiple external resonant cavities.
5. The noise reduction device for a nitrogen generator according to claim 1, characterized in that: The main silencer pipe (2) passes through the first partition (401) and the second partition (402), and the auxiliary silencer pipe (3) passes through the second partition (402) and the third partition (403).
6. The noise reduction device for a nitrogen generator according to claim 3, characterized in that: The surface of the second partition (402) is provided with a flow hole (404) for gas flow.
7. The noise reduction device for a nitrogen generator according to claim 1, characterized in that: The surface of the spiral blade (5) is provided with several through holes (8).