Silent generator set with multi-stage noise reduction mechanism

Abstract

The utility model discloses a silent generator set with a multi-stage noise reduction mechanism. The silent generator set comprises an outer shell, a power unit, a multi-stage noise reduction assembly and an installation frame. The outer shell adopts a double-layer structure and an elastic connecting piece to reduce vibration transmission, and the power unit is installed through a damping cushion block and a sliding rail and is convenient to maintain. The multi-stage noise reduction assembly comprises a first-stage silencer, a second-stage resonant cavity and a third-stage sound absorption plate which are used for controlling high-frequency noise, intermediate-frequency noise and low-frequency noise respectively. The air inlet flow guide cover and the air outlet axial flow fan optimize the airflow path, and airflow noise is reduced. The supporting legs are adjustable and are provided with anti-skid rubber pads, so that the stability is improved. Through multi-stage noise reduction and structure optimization, the noise problem is remarkably improved, the system is suitable for industrial and civil scenes, and quiet and comfortable experience is provided.

Description

Technical Field

[0001] This utility model relates to the field of power generation equipment and noise reduction technology, and in particular to a silent generator set with a multi-stage noise reduction mechanism. Background Technology

[0002] Generator sets are widely used in various industrial and civilian applications, especially in situations requiring continuous power supply, where noise levels are a major concern. Traditional generator sets generate significant noise during operation due to engine combustion, mechanical vibration, and airflow disturbances, particularly at night or in noise-sensitive environments. To reduce noise, some generator sets employ single noise reduction structures, such as adding sound-absorbing materials or installing silencing channels within the casing. However, due to the complex sources and wide frequency spectrum of noise, single noise reduction measures often fail to achieve ideal quiet operation. Furthermore, existing noise reduction designs typically focus on noise control in specific frequency bands while neglecting the sound propagation characteristics of other frequency bands, resulting in limitations in overall noise reduction performance and room for improvement in user experience. Utility Model Content

[0003] The purpose of this utility model is to provide a silent generator set with a multi-stage noise reduction mechanism, which solves the problems mentioned in the background art.

[0004] This invention is implemented as follows: a silent generator set with a multi-stage noise reduction mechanism. The generator set mainly consists of an outer shell, a power unit housed inside the outer shell, multi-stage noise reduction components connected to the power unit, and a mounting frame for fixing and supporting the various components. The outer shell adopts a double-layer structure design: the outer layer is a protective shell made of metal, and the inner layer is a sound insulation layer made of high-density sound-absorbing material. The two layers are fixedly connected by elastic connectors, which are evenly distributed between the inner and outer layers to reduce vibration transmission. The power unit includes an engine and a generator, both fixed to the mounting frame by vibration-damping pads. The bottom of the mounting frame has a slide rail embedded in a guide groove at the bottom of the outer shell, allowing the power unit to move horizontally within the guide groove for easy inspection and maintenance.

[0005] The multi-stage noise reduction assembly includes a primary muffler, a secondary resonant cavity, and a tertiary sound-absorbing panel. The primary muffler is located at the engine exhaust port and contains multiple inclined baffles coated with a high-temperature sound-absorbing layer. The baffles form a tortuous airflow channel to reduce high-frequency noise. The secondary resonant cavity is located behind the primary muffler and contains multiple resonant tubes of different diameters. The length and diameter of the resonant tubes are designed according to a specific frequency range to specifically absorb mid-frequency noise. The tertiary sound-absorbing panel is located on the inner wall of the outer casing. The panel is made of multi-layered composite material, including a surface microporous sound-absorbing membrane, a middle honeycomb sound-absorbing core, and a bottom damping layer. These three layers are bonded together using a hot-pressing process, effectively absorbing low-frequency noise and suppressing resonance.

[0006] The top of the outer casing has an air inlet, inside which is installed a flow guide. The flow guide has an arc-shaped design and contains spiral guide vanes coated with sound-absorbing material to guide the airflow smoothly into the casing and to initially attenuate airflow noise. The side walls of the outer casing have air outlets, inside which are installed axial flow fans. The blades of the axial flow fan have a biomimetic design with tiny grooves on their surface to reduce noise generated by airflow turbulence. The axial flow fan is bolted to the inner side wall of the outer casing, and its motor is isolated from the casing by rubber vibration damping sleeves to further reduce mechanical vibration noise.

[0007] The mounting frame has adjustable height support feet at its four corners, which are threaded to the frame. Each foot has a rubber pad with anti-slip texture on its bottom to enhance overall stability and reduce ground vibration feedback. An access door is located on the front of the housing, connected to it by hinges with built-in damping mechanisms to control the door's opening and closing speed. The access door is surrounded by a flexible sealing strip to effectively prevent noise leakage.

[0008] This invention utilizes the synergistic effect of multi-stage noise reduction components to employ different noise reduction measures for high-frequency, mid-frequency, and low-frequency noise, achieving effective noise control across the entire frequency band. The double-layer structure design of the outer casing, combined with the application of elastic connectors, significantly reduces the propagation of vibration noise. The power unit, installed using a combination of vibration-damping pads and slide rails, ensures operational stability while facilitating subsequent maintenance. The biomimetic blade design of the axial flow fan and the spiral guide vanes of the air guide shroud work together to reduce the impact of airflow noise. The height-adjustable design of the support feet and the anti-slip treatment of the rubber pads enhance the adaptability of the equipment in different operating environments.

[0009] This invention features a compact structure and convenient installation. The connections between its components are clear and specific, enabling mass production through standardized manufacturing processes. Through the comprehensive application of the aforementioned technical means, this invention significantly improves the noise problem of generator sets, making it particularly suitable for noise-sensitive industrial and residential applications, providing users with a quieter and more comfortable experience. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the overall structure of the present invention, showing the layout relationship of the generator set's outer casing, power unit, multi-stage noise reduction components, and mounting frame. The top of the outer casing is provided with an air inlet and a guide shroud, while the side wall is provided with an air outlet and an axial flow fan.

[0011] Figure 2 This is an exploded view of the structure of a multi-stage noise reduction assembly, which shows in detail the arrangement and internal structure of the noise reduction components, including the first-stage muffler, the second-stage resonant cavity, and the third-stage sound-absorbing panel, highlighting the functional zones of each stage of the noise reduction assembly.

[0012] Figure 3 The diagram shows the connection details between the outer casing and the mounting frame, highlighting the fit between the bottom slide rail of the mounting frame and the guide groove of the outer casing, as well as the specific structure of the support feet and rubber pads.

[0013] The attached diagram is labeled as follows: 1. Outer casing; 2. Power unit; 3. Primary silencer; 4. Secondary resonant cavity; 5. Tertiary sound-absorbing panel; 6. Mounting frame; 7. Draft shield; 8. Axial flow fan; 9. Support feet; 10. Inspection door. Detailed Implementation

[0014] This utility model provides a silent generator set with a multi-stage noise reduction mechanism, the overall structure of which is as follows: Figure 1 As shown, the system includes an outer casing 1, a power unit 2, multi-stage noise reduction components, and a mounting frame 6. The outer casing 1 employs a double-layer structure: an outer protective shell made of metal and an inner sound insulation layer composed of high-density sound-absorbing material. The two layers are fixedly connected by elastic connectors. These elastic connectors are evenly distributed between the inner and outer layers and are specifically a bolt-and-rubber-washer structure used to reduce vibration transmission. The power unit 2 consists of an engine and a generator, both fixed to the mounting frame 6 by vibration-damping pads. The mounting frame 6 has a slide rail at its bottom, which is embedded in a guide groove at the bottom of the outer casing 1, allowing the power unit 2 to move horizontally within the guide groove for easy inspection and maintenance.

[0015] The multi-stage noise reduction assembly includes a primary silencer 3, a secondary resonant cavity 4, and a tertiary sound-absorbing panel 5, the specific arrangement of which is as follows: Figure 2As shown. The primary muffler 3 is located at the engine exhaust port and contains multiple inclined baffles. The surface of the baffles is coated with a high-temperature resistant sound-absorbing coating, and the baffles form a tortuous airflow channel. The primary muffler 3 is connected to the engine exhaust port via a flange, and a sealing gasket is provided on the flange to prevent gas leakage. The secondary resonant cavity 4 is located behind the primary muffler 3. Its cavity contains multiple resonant tubes of different diameters. The length and diameter of the resonant tubes are designed according to a specific frequency range. The resonant tubes are fixed to the inner wall of the secondary resonant cavity 4 by a bracket, and the bracket is connected to the inner wall by screws. The tertiary sound-absorbing panel 5 is located on the inner wall of the outer shell 1. The sound-absorbing panel 5 is made of multi-layer composite material, including a microporous sound-absorbing membrane on the surface, a honeycomb sound-absorbing core material in the middle layer, and a damping layer at the bottom. The three are combined into one piece by a hot-pressing process. The sound-absorbing panel 5 is fixed to the inner wall of the outer shell 1 by a snap-fit ​​structure. The snap-fit ​​structure is made of plastic and has a certain degree of elasticity to facilitate installation and disassembly.

[0016] The top of the outer casing 1 has an air inlet, inside which a guide shroud 7 is installed. The guide shroud 7 has an arc-shaped design and contains spiral guide vanes with sound-absorbing material coated on their surfaces. The guide shroud 7 is fixed to the top of the outer casing 1 with four bolts evenly distributed around its perimeter. The side wall of the outer casing 1 has an air outlet, inside which an axial flow fan 8 is installed. The blades of the axial flow fan 8 have a biomimetic design, with tiny grooves on their surface. The axial flow fan 8 is fixed to the inner side wall of the outer casing 1 with bolts. Its motor is isolated from the outer casing 1 by a rubber vibration damping sleeve, which is installed between the motor housing and the outer casing 1 with an interference fit. The axial flow fan 8 has five blades, each 10mm wide and 2mm thick, with a 72-degree angle between the blades. The tiny grooves on the blade surfaces are 0.5mm deep and 1mm wide.

[0017] The mounting frame 6 has adjustable support feet 9 at its four corners. The support feet 9 are connected to the mounting frame 6 via threads, and each support foot 9 has a rubber pad with anti-slip texture on its bottom. The height adjustment range of the support feet 9 is 0 to 50 mm, the thread pitch is 2 mm, and the height is adjusted by 2 mm per rotation. The front of the outer casing 1 has an access door 10, which is connected to the outer casing 1 via a hinge. The hinge has a built-in damping device consisting of hydraulic oil and a piston. The piston moves synchronously with the hinge's rotation axis to control the opening and closing speed of the access door 10. The access door 10 is surrounded by sealing strips made of flexible material, with a thickness of 3 mm and a width of 10 mm. The sealing strips are fixed to the perimeter of the access door 10 with adhesive.

[0018] The connection details between the outer casing 1 and the mounting frame 6 are as follows: Figure 3As shown, the slide rail at the bottom of the mounting frame 6 mates with the guide groove at the bottom of the outer casing 1. The slide rail has a T-shaped cross-section, and the guide groove has a U-shaped cross-section. The slide rail is embedded in the guide groove and fixed with bolts. The slide rail is 1000mm long, 20mm wide, and 10mm high. The guide groove is 1020mm long, 22mm wide, and 12mm high. A 1mm gap is left between the slide rail and the guide groove to facilitate sliding. The mounting frame 6 is made of aluminum alloy with a thickness of 5mm. Reinforcing ribs are provided at the four corners of the mounting frame 6. The reinforcing ribs are 10mm thick and 20mm wide, and are fixed to the mounting frame 6 by welding.

[0019] When the power unit 2 is running, the exhaust gas generated by the engine is discharged through the primary muffler 3. The exhaust gas flows through the tortuous airflow channel inside the primary muffler 3, and the baffles provide initial attenuation of high-frequency noise. After being treated by the primary muffler 3, the exhaust gas enters the secondary resonant cavity 4, where it flows through the resonant tube, which absorbs mid-frequency noise. The exhaust gas is finally discharged through the tertiary sound-absorbing plate 5, which absorbs low-frequency noise inside the outer casing 1 and suppresses resonance. The air guide shroud 7 on the top of the outer casing 1 guides external air to enter the interior of the outer casing 1 smoothly, and the spiral guide vanes inside the air guide shroud 7 provide initial attenuation of airflow noise. The axial flow fan 8 on the side wall of the outer casing 1 draws out the internal air. The biomimetic blade design and the tiny grooves on the blade surface of the axial flow fan 8 work together to reduce noise generated by airflow disturbance. The motor of the axial flow fan 8 is isolated from the outer casing 1 by a rubber damping sleeve, further reducing mechanical vibration noise.

[0020] The support feet 9 of the mounting frame 6 are height-adjustable according to ground conditions. Rubber pads at the bottom of the support feet 9 enhance the overall stability of the equipment and reduce ground vibration feedback. When the access door 10 is opened via hinges, the damping device built into the hinges controls the opening and closing speed of the access door 10, preventing damage caused by rapid closure. The sealing strips around the access door 10 effectively prevent noise leakage, ensuring that noise inside the housing 1 does not propagate to the external environment. The double-layer structure design of the housing 1, combined with the application of elastic connectors, significantly reduces the propagation of vibration noise. The power unit 2, installed using a combination of vibration damping pads and slide rails, ensures operational stability and facilitates subsequent maintenance. The biomimetic blade design of the axial flow fan 8 and the spiral guide vanes of the guide shroud 7 work together to reduce the impact of airflow noise. The height-adjustable design of the support feet 9 and the anti-slip treatment of the rubber pads enhance the adaptability of the equipment in different operating environments.

[0021] This invention relates to a silent generator set suitable for noise-sensitive industrial and civilian applications. Its compact structure and clearly defined component connections enable mass production through standardized manufacturing processes. The double-layer structure of the outer casing 1, combined with the application of elastic connectors, significantly reduces the propagation of vibration noise. The power unit 2, installed using a combination of vibration-damping pads and slide rails, ensures operational stability while facilitating subsequent maintenance. The biomimetic blade design of the axial flow fan 8 and the spiral guide vanes of the flow deflector 7 work together to reduce the impact of airflow noise. The height-adjustable design of the support feet 9 and the anti-slip treatment of the rubber pads enhance the adaptability of the equipment in different operating environments.

[0022] To enable those skilled in the art to fully understand and implement this utility model, the following supplementary explanation of the specific implementation principle of this utility model is provided in conjunction with a specific application scenario.

[0023] First, when the generator set starts running, the exhaust gas produced by the engine is discharged through the first-stage muffler 3. For example... Figure 2 As shown, the primary muffler 3 contains multiple inclined baffles, each coated with a high-temperature resistant sound-absorbing coating. The baffles form a tortuous airflow channel. As the exhaust gas passes through these baffles, the frequent changes in airflow direction gradually dissipate the energy of high-frequency noise, thus achieving initial attenuation. The key to this process lies in the design of the baffle's inclination angle and spacing, which effectively extends the flow path of the exhaust gas within the primary muffler 3, increasing the contact time between the noise and the sound-absorbing coating, thereby improving the noise reduction effect.

[0024] Subsequently, the exhaust gas, after being treated by the primary silencer 3, enters the secondary resonant cavity 4. The secondary resonant cavity 4 contains multiple resonant tubes of different diameters. The length and diameter of the resonant tubes are designed according to a specific frequency range to absorb mid-frequency noise. When the exhaust gas flows through the resonant tubes, the air column inside the tubes vibrates due to the resonance effect, thereby converting the energy of the mid-frequency noise into heat energy and dissipating it. The resonant tubes are fixed to the inner wall of the secondary resonant cavity 4 by supports. The screw connection between the supports and the inner wall ensures the stability of the resonant tubes while avoiding additional noise caused by vibration.

[0025] The exhaust gas is finally discharged through the three-stage sound-absorbing panel 5. For example... Figure 2As shown, the three-stage sound-absorbing panel 5 is installed on the inner wall of the outer casing 1 and is made of multi-layer composite material, including a surface microporous sound-absorbing membrane, a middle honeycomb sound-absorbing core material, and a bottom damping layer. When exhaust gas passes through the three-stage sound-absorbing panel 5, the energy of low-frequency noise is absorbed layer by layer, and the special structure of the honeycomb sound-absorbing core material effectively suppresses resonance. The sound-absorbing panel 5 is fixed to the inner wall of the outer casing 1 by a snap-fit ​​structure. The elastic design of the snap-fit ​​structure makes installation and disassembly more convenient, while ensuring a tight fit between the sound-absorbing panel 5 and the outer casing 1, preventing noise leakage.

[0026] Meanwhile, the air deflector 7 on the top of the outer casing 1 guides external air smoothly into the interior of the outer casing 1. The spiral-shaped guide vanes inside the air deflector 7 split and guide the airflow, and the sound-absorbing material coated on its surface further attenuates airflow noise. The air deflector 7 is fixed to the top of the outer casing 1 by four evenly distributed bolts, ensuring its stability during operation. The axial flow fan 8 on the side wall of the outer casing 1 extracts internal air; its blades feature a biomimetic design, with tiny grooves on the blade surface effectively reducing noise generated by airflow disturbance. The motor of the axial flow fan 8 is isolated from the outer casing 1 by a rubber vibration damping sleeve, further reducing the transmission of mechanical vibration noise.

[0027] During equipment operation, the slide rail at the bottom of the mounting frame 6 engages with the guide groove at the bottom of the outer casing 1, allowing the power unit 2 to move horizontally within the guide groove. This design not only facilitates inspection and maintenance but also ensures the smooth operation of the power unit 2 through the 1mm gap between the slide rail and the guide groove. The support feet 9 at the four corners of the mounting frame 6 are height-adjustable according to ground conditions. The rubber pads at the bottom of the support feet 9 enhance the overall stability of the equipment and reduce ground vibration feedback. The height adjustment range of the support feet 9 is 0 to 50mm, with a 2mm adjustment per rotation. This design significantly improves the adaptability of the equipment in different operating environments.

[0028] When the access door 10 is opened via the hinge, the damping device built into the hinge controls the opening and closing speed of the access door 10 to prevent damage caused by rapid closure. The sealing strip embedded around the access door 10 effectively prevents noise leakage, ensuring that noise inside the outer casing 1 does not propagate to the external environment. The sealing strip is made of flexible material, 3mm thick and 10mm wide, and is fixed to the perimeter of the access door 10 with adhesive, ensuring both sealing performance and easy replacement later.

[0029] In summary, this invention achieves effective noise control across the entire frequency band through the synergistic effect of multi-stage noise reduction components and the rational design of each part. The double-layer structure design of the outer shell 1, combined with the application of elastic connectors, significantly reduces the propagation of vibration noise; the power unit 2, through the combination of vibration damping pads and slide rails, ensures operational stability and facilitates subsequent maintenance; the biomimetic blade design of the axial flow fan 8 and the spiral guide vanes of the guide shroud 7 work together to reduce the impact of airflow noise; the height-adjustable design of the support feet 9 and the anti-slip treatment of the rubber pads further enhance the adaptability of the equipment in different operating environments. The comprehensive application of the above-mentioned technical means makes this invention widely applicable in noise-sensitive industrial and civilian scenarios.

[0030] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A silent generator set with a multi-stage noise reduction mechanism, characterized in that, The generator set includes an outer shell (1), a power unit (2) located inside the outer shell (1), a multi-stage noise reduction assembly connected to the power unit (2), and an installation frame (6) for fixing and supporting the components. The outer shell (1) adopts a double-layer structure design. The outer layer is a protective shell made of metal material, and the inner layer is a sound insulation layer made of high-density sound-absorbing material. The two layers are fixedly connected by elastic connectors. The power unit (2) includes an engine and a generator. The two are fixed on the installation frame (6) by vibration damping pads. The bottom of the installation frame (6) is provided with a slide rail, which is embedded in the guide groove at the bottom of the outer shell (1).

2. A silent generator set with a multi-stage noise reduction mechanism according to claim 1, characterized in that: The multi-stage noise reduction assembly includes a primary muffler (3), a secondary resonant cavity (4), and a tertiary sound-absorbing plate (5). The primary muffler (3) is located at the engine exhaust port and has multiple inclined baffles inside, forming a tortuous airflow channel between the baffles. The secondary resonant cavity (4) is located behind the primary muffler (3) and has multiple resonant tubes of different diameters inside. The tertiary sound-absorbing plate (5) is located on the inner wall of the outer shell (1) and is made of multiple layers of composite material, including a microporous sound-absorbing membrane on the surface, a honeycomb sound-absorbing core material in the middle layer, and a damping layer at the bottom.

3. A silent generator set with a multi-stage noise reduction mechanism according to claim 2, characterized in that: The baffle surface of the first-stage muffler (3) is coated with a high-temperature resistant sound-absorbing coating. The tortuous airflow channel between the baffles is used to guide the flow of exhaust gas. The resonant tube of the second-stage resonant cavity (4) is fixed to the inner wall of the cavity by a bracket. The bracket and the inner wall are connected by screws. The third-stage sound-absorbing plate (5) is fixed to the inner wall of the outer shell (1) by a snap-fit ​​structure. The snap-fit ​​structure is made of plastic.

4. A silent generator set with a multi-stage noise reduction mechanism according to claim 1, characterized in that: The top of the outer shell (1) is provided with an air inlet, and a guide shroud (7) is installed inside the air inlet. The guide shroud (7) is arc-shaped and has spiral guide vanes inside. The side wall of the outer shell (1) is provided with an air outlet, and an axial flow fan (8) is installed inside the air outlet. The blades of the axial flow fan (8) are biomimetic and have tiny grooves on the surface of the blades.

5. A silent generator set with a multi-stage noise reduction mechanism according to claim 4, characterized in that: The flow guide (7) is fixed to the top of the outer shell (1) by bolts. There are four bolts, which are evenly distributed around the flow guide (7). The axial flow fan (8) is fixed to the inner wall of the outer shell (1) by bolts. Its motor part is isolated from the outer shell (1) by rubber vibration damping sleeve.

6. A silent generator set with a multi-stage noise reduction mechanism according to claim 1, characterized in that: The four corners of the mounting frame (6) are provided with height-adjustable support feet (9). The support feet (9) are connected to the mounting frame (6) by threads. The bottom of the support feet (9) is provided with rubber pads, and the surface of the rubber pads is provided with anti-slip texture.

7. A silent generator set with a multi-stage noise reduction mechanism according to claim 1, characterized in that: The front side of the outer shell (1) is provided with an inspection door (10). The inspection door (10) is connected to the outer shell (1) by a hinge. The hinge has a built-in damping device. The inspection door (10) is surrounded by a sealing strip. The sealing strip is fixed around the inspection door (10) by an adhesive.

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