A composite impedance silencing ventilation device for grain bins

Abstract

This utility model discloses an impedance composite silent ventilation device for grain storage, comprising a low-noise power unit and an impedance composite ventilation duct unit. The low-noise power unit includes a silent circulating fan, a vibration-damping base installed below it, a canvas flexible connector between the air outlet of the silent circulating fan and the impedance composite ventilation duct unit, and a noise-reducing metal cover covering the exterior of the low-noise power unit. The impedance composite ventilation duct unit includes a sound-absorbing vent unit sealed to the canvas flexible connector, and an impedance composite sound-absorbing pipe section connected in series with the sound-absorbing vent unit. The impedance composite sound-absorbing pipe section includes an outer shell, a perforated inner tube disposed inside the outer shell, a sound-absorbing and heat-insulating layer filled between the outer shell and the perforated inner tube, and a protective layer covering the inner wall surface of the perforated inner tube. In summary, this utility model has the advantages of compact structure, fire and dust resistance, safety and reliability, convenient maintenance, high noise reduction efficiency, and smooth ventilation.

Description

Technical Field

[0001] This utility model belongs to the field of grain safe storage technology, specifically relating to an impedance composite silent ventilation device for grain warehouses. Background Technology

[0002] Grain silos require regular mechanical ventilation during grain storage to regulate temperature and humidity, prevent mold and pests, and ensure grain quality and storage safety. The ventilation system typically consists of circulation ducts, fans, and vents. During operation, the aerodynamic noise and mechanical vibration noise generated by the fans will propagate along the ducts, significantly increasing the noise level inside and outside the silo. This not only affects the working environment of staff but also easily disturbs noise-sensitive areas such as surrounding residential areas and office areas. Long-term operation can also lead to equipment structural fatigue and resonance risks.

[0003] Currently, the common noise reduction method is to install ordinary silencers or simple soundproof covers at the fan outlet. However, such structures have many shortcomings. Ordinary silencers are difficult to directly integrate with the circulating ventilation systems commonly used in grain silos. The installation process can easily damage the original insulation layer structure. In addition, their silencing frequency band is narrow, and their effect on suppressing low-frequency noise is limited. Furthermore, the sound-absorbing materials used in some silencers have poor fire resistance and moisture resistance, which can easily cause fiber shedding and dust pollution during operation. This not only affects the lifespan of the equipment but also poses risks of grain contamination and safety hazards. Therefore, the existing grain silo ventilation systems have significant deficiencies in terms of noise reduction efficiency, interface compatibility, and safety and hygiene, and cannot meet the needs of existing grain storage.

[0004] To address this, we propose an impedance composite silent ventilation device for grain storage, which can efficiently collect and reliably transmit the sound of pest activity inside the grain pile, solving the problems of complex installation, insufficient noise reduction effect, and low safety performance in existing technologies. Utility Model Content

[0005] In view of this, this utility model proposes an impedance composite silent ventilation device for grain warehouses, which is applied to the field of grain safe storage technology to solve the existing technical problems of complex installation process, insufficient noise reduction effect and low safety performance.

[0006] To achieve the above-mentioned technical objectives, the specific technical solution adopted by this utility model is as follows: An impedance composite silent ventilation device for grain storage includes a low-noise power unit and an impedance composite ventilation duct unit. The low-noise power unit drives the ventilation airflow, and the impedance composite ventilation duct unit achieves silent airflow delivery. The low-noise power unit includes a silent circulating fan, a vibration-damping base installed below it, a canvas flexible connector between the outlet of the silent circulating fan and the impedance composite ventilation duct unit, and a noise-reducing metal cover covering the exterior of the low-noise power unit. The impedance composite ventilation duct unit includes a silencer vent unit sealed to the canvas flexible connector, and an impedance composite silencer pipe section connected in series with the silencer vent unit. The impedance composite silencer pipe section includes an outer shell, a perforated inner tube disposed inside the outer shell, a sound-absorbing and heat-insulating layer filled between the outer shell and the perforated inner tube, and a protective layer covering the inner wall surface of the perforated inner tube. The impedance composite silencer pipe section is arranged in the same direction as the airflow direction to achieve broadband attenuation of airflow noise without increasing ventilation resistance.

[0007] Furthermore, the perforated inner tube has uniformly distributed through holes on its wall, with an opening rate in the range of 15% to 25%. The sound-absorbing and heat-insulating layer is made of hydrophobic centrifugal glass wool, and the protective layer is alkali-free glass fiber cloth.

[0008] Furthermore, both the outer casing and the silencer vent unit are equipped with outer tubes. The outer diameters of the outer tubes in the outer casing and the silencer vent unit are the same, and the two ends of the corresponding outer tubes are connected by flanges to form a sealed channel.

[0009] Furthermore, the inner wall of the noise-reducing metal casing is equipped with a conical sound-absorbing structure layer to absorb the medium and high frequency noise generated by the operation of the silent circulating fan.

[0010] Furthermore, the impedance composite ventilation duct unit is coaxially arranged with the grain warehouse circulation ventilation main, and the outer shell is equipped with a heat insulation sleeve to reduce heat loss and maintain a stable airflow temperature inside the ventilation duct.

[0011] Furthermore, the outlet end of the perforated inner tube is equipped with a guide cone structure aligned with the airflow direction. The guide cone is conical or trumpet-shaped and is used to guide the airflow to be discharged evenly along the tube wall, thereby reducing turbulence and lowering ventilation resistance.

[0012] By adopting the above technical solution, this utility model can also bring the following beneficial effects: 1. This utility model discloses an impedance composite silent ventilation device for grain storage, which is equipped with a low-noise power unit and an impedance composite ventilation duct unit. Through the synergistic structure of the silent circulating fan, vibration damping base, and canvas flexible connector, the mechanical vibration and aerodynamic noise during operation are effectively reduced, weakening noise propagation at the source. The ventilation duct part of the impedance composite ventilation duct unit adopts an impedance composite sound-absorbing pipe section structure. The perforated inner pipe, sound-absorbing insulation layer, and protective layer are matched to form a broadband sound-absorbing system, which reflects and attenuates low-frequency noise and effectively absorbs mid- and high-frequency noise. The airflow is evenly distributed and the flow resistance is small. At the same time, a guide cone structure is set at the air outlet of the pipe section to make the airflow smoothly discharged along the pipe wall, further reducing turbulence and improving the silent effect. It has the advantages of compact structure, high noise reduction efficiency, and smooth ventilation.

[0013] 2. This utility model discloses an impedance composite silent ventilation device for grain storage, which adopts modular sealed connection of different components. The silencer ventilation port unit and the silencer pipe section are connected by flanges, which makes installation and maintenance convenient. The outer shell and noise reduction metal cover are made of corrosion-resistant and non-combustible materials. The sound-absorbing layer is covered with alkali-free glass fiber cloth. An external heat insulation sleeve is provided to effectively prevent heat loss and dust diffusion. The entire system operates stably for a long time and is not affected by seasonal temperature differences and humidity changes in the storage room. It can maintain continuous silence and efficient ventilation performance in complex grain storage environments. It has the advantages of fireproof and dustproof, safe and reliable and easy to maintain. Attached Figure Description

[0014] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 This is a schematic diagram of the structure of an impedance composite silent ventilation device for grain storage mentioned in this utility model; Figure 2 This is a schematic diagram of the impedance composite ventilation duct unit in this embodiment; Figure 3 This is a schematic diagram of the module frame of an impedance composite silent ventilation device for grain storage in this embodiment; In the diagram: 1. Silent circulating fan; 2. Vibration damping base; 3. Canvas flexible connector; 4. Noise-reducing metal cover; 5. Noise-absorbing ventilation unit; 6. Impedance composite silencer pipe section; 601. Outer shell; 602. Perforated inner pipe; 603. Sound-absorbing and heat-insulating layer; 604. Protective layer. Detailed Implementation

[0016] The embodiments of this utility model will now be described in detail with reference to the accompanying drawings.

[0017] The following specific examples illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of this utility model, not all of them. This utility model can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this utility model. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. 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.

[0018] It should be noted that various aspects of embodiments within the scope of the appended claims are described below. It will be apparent that the aspects described herein can be embodied in a wide variety of forms, and any particular structure and / or function described herein is merely illustrative. Based on this invention, those skilled in the art will understand that one aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number of aspects set forth herein can be used to implement the device and / or practice the method. Additionally, this device and / or method can be implemented using other structures and / or functionalities besides one or more of the aspects set forth herein.

[0019] It should also be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. The drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components. In actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0020] Furthermore, specific details are provided in the following description to facilitate a thorough understanding of the examples. However, those skilled in the art will understand that the described aspects can be practiced without these specific details. Example 1

[0021] like Figures 1 to 3As shown, a grain silo-type impedance composite silent ventilation device includes a low-noise power unit and an impedance composite ventilation duct unit. The low-noise power unit consists of a silent circulating fan 1, a vibration-damping base 2 installed below the silent circulating fan 1, a canvas flexible connector 3 located between the outlet of the silent circulating fan 1 and the inlet of the impedance composite ventilation duct unit, and a noise-reducing metal cover 4 covering the exterior of the low-noise power unit. The silent circulating fan 1, as the power source of the entire grain silo-type impedance composite silent ventilation device, adopts a low-noise, high-efficiency impeller structure, which can maintain a stable airflow at a low speed. The vibration-damping base 2 adopts a design that combines a rubber vibration isolation layer with a composite elastic support component, and has an anti-slip pad at the bottom, which can effectively reduce mechanical vibration and noise propagation. The canvas flexible connector 3 absorbs operating vibration and displacement differences through a flexible fabric layer, preventing resonance and air impact noise from propagating along the impedance composite ventilation duct unit, while ensuring a sealed connection.

[0022] The noise-reducing metal cover 4 covers the entire exterior of the low-noise power unit. The inner wall of the noise-reducing metal cover 4 is covered with a conical sound-absorbing structure layer. The noise-reducing metal cover 4 adopts a detachable and fixed method for easy maintenance. The conical sound-absorbing structure layer is formed by bonding perforated galvanized sheet, fiberglass felt and flame-retardant composite layer. It is used to absorb the medium and high frequency noise generated by the silent circulating fan 1 during operation and further reduce residual noise during the operation of the device. The exterior of the noise-reducing metal cover 4 is equipped with a protective net to prevent collision with foreign objects and facilitate handling and installation.

[0023] The impedance composite ventilation duct unit includes a silencer vent unit 5 sealed to the canvas flexible connector 3 and an impedance composite silencer pipe section 6 connected in series with the silencer vent unit 5. The two are connected by a flange to form a sealed channel. The silencer vent unit 5 is arranged coaxially with the grain silo circulating ventilation main. Guide grilles are set at the inlet and outlet positions of the silencer vent unit 5 to evenly distribute the airflow and prevent the airflow from deflecting and turbulence.

[0024] The impedance composite silencer section 6 consists of an outer shell 601, a perforated inner tube 602, a sound-absorbing and heat-insulating layer 603, and a protective layer 604. The perforated inner tube 602 is located inside the outer shell 601. The tube wall of the perforated inner tube 602 has uniformly distributed through-holes with an opening rate of 15%–25%. The uniform arrangement of the through-holes allows for multiple reflections and dissipation of sound energy in the perforated area, achieving broadband noise reduction. The perforated inner tube 602 is made of stainless steel, and its inner wall is anodized to enhance corrosion resistance. A guide cone structure is installed at the outlet end of the perforated inner tube 602. The guide cone structure is conical and aligned with the airflow direction, guiding the airflow smoothly out along the tube wall, reducing turbulence and ventilation resistance. The guide cone structure and the perforated inner tube 602 are connected by a detachable flange for easy cleaning and replacement.

[0025] A sound-absorbing and heat-insulating layer 603 is filled between the outer shell 601 and the perforated inner tube 602. The sound-absorbing and heat-insulating layer 603 is made of hydrophobic centrifugal glass wool; rock wool or composite porous fiber materials can also be selected as needed to improve moisture resistance. A protective layer 604 covers the inner wall surface of the perforated inner tube 602. The protective layer 604 is made of alkali-free glass fiber cloth to prevent fiber particles from entering the airflow and maintain air cleanliness. The outer shell 601 is made of galvanized steel plate, and its outer surface is coated with an anti-corrosion layer. The outer shell 601 of the impedance composite ventilation duct unit is covered with an insulation sleeve to reduce heat loss and maintain a stable airflow temperature within the duct. The entire impedance composite ventilation duct unit adopts a modular design, and is segmented and combined according to the grain silo volume and airflow requirements.

[0026] During operation, after the silent circulating fan 1 starts, air enters the canvas flexible connector 3 through the outlet of the silent circulating fan 1 supported by the vibration damping base 2. The flexible interface of the canvas flexible connector 3 absorbs the vibration generated during operation, and the airflow sequentially enters the silencer ventilation unit 5 and the impedance composite silencer pipe section 6. In the silencer ventilation unit 5, the air is evenly distributed by the guide grille, and then passes through the composite acoustic impedance structure formed by the perforated inner pipe 602 and the sound-absorbing and heat-insulating layer 603. The noise is reflected multiple times between the porous layers and absorbed. The mid-to-high frequency noise generated by the operation of the silent circulating fan 1 and the airflow it produces is significantly reduced, thereby greatly reducing the noise of the entire grain silo impedance composite silent ventilation device during operation. In summary, the grain silo impedance composite silent ventilation device of this utility model achieves full suppression from the noise source to the propagation path through the synergistic effect of the low-noise power unit, the impedance composite ventilation pipe unit, and the canvas flexible connector 3. It has the advantages of compact structure, fireproof and dustproof, safe and reliable, convenient maintenance, high noise reduction efficiency, and smooth ventilation.

[0027] The above description is merely a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the scope of the claims.

Claims

1. A composite impedance-type silent ventilation device for grain silos, characterized in that: The system includes a low-noise power unit and an impedance composite ventilation duct unit. The low-noise power unit drives the ventilation airflow, and the impedance composite ventilation duct unit achieves silent airflow delivery. The low-noise power unit includes a silent circulating fan, a vibration-damping base installed below it, a canvas flexible connector between the outlet of the silent circulating fan and the impedance composite ventilation duct unit, and a noise-reducing metal cover covering the exterior of the low-noise power unit. The impedance composite ventilation duct unit includes a silencer vent unit sealed to the canvas flexible connector and an impedance composite silencer pipe section connected in series with the silencer vent unit. The impedance composite silencer pipe section includes an outer shell, a perforated inner tube disposed inside the outer shell, a sound-absorbing and heat-insulating layer filled between the outer shell and the perforated inner tube, and a protective layer covering the inner wall surface of the perforated inner tube. The impedance composite silencer pipe section is oriented in the same direction as the airflow direction to achieve broadband attenuation of airflow noise without increasing ventilation resistance.

2. The impedance composite silent ventilation device for grain silos according to claim 1, characterized in that: The perforated inner tube has uniformly distributed through holes on its wall, with an opening rate in the range of 15% to 25%. The sound-absorbing and heat-insulating layer is made of hydrophobic centrifugal glass wool, and the protective layer is alkali-free glass fiber cloth.

3. The impedance composite silent ventilation device for grain silos according to claim 2, characterized in that: Both the outer casing and the silencer vent unit are equipped with an outer tube. The outer diameter of the outer tube in the outer casing and the silencer vent unit is the same, and the two ends of the corresponding outer tube are connected by flanges to form a sealed channel.

4. The impedance composite silent ventilation device for grain silos according to claim 3, characterized in that, The inner wall of the noise-reducing metal casing is provided with a conical sound-absorbing structure layer, which is used to absorb the medium and high frequency noise generated by the operation of the silent circulating fan.

5. The impedance composite silent ventilation device for grain silos according to claim 4, characterized in that: The impedance composite ventilation duct unit is arranged coaxially with the grain warehouse circulation ventilation main, and the outer shell is equipped with a heat insulation sleeve to reduce heat loss and maintain a stable airflow temperature inside the ventilation duct.

6. The impedance composite silent ventilation device for grain silos according to claim 5, characterized in that: The outlet end of the perforated inner tube is provided with a guide cone structure that is aligned with the airflow direction. The guide cone is conical or trumpet-shaped and is used to guide the airflow to be discharged evenly along the tube wall, so as to reduce turbulence and reduce ventilation resistance.

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