A mixed flow ventilator

Abstract

A mixed-flow ventilation fan includes a base plate and a panel that snaps onto it. An exhaust pipe is connected to the rear of the base plate. An air inlet is provided on the panel, communicating with the exhaust pipe on the base plate. A motor mount is connected to the inner wall of the exhaust pipe via several guide vanes. The motor mount is fixed to the central axis of the exhaust pipe by the guide vanes. A drive motor is installed inside the motor mount, and a front fan blade is mounted on the main shaft of the drive motor. The front fan blade rotates inside the exhaust pipe, drawing in air from the air inlet and expelling it from the rear of the exhaust pipe. The beneficial effects of this invention are: the front fan blade is a mixed-flow fan blade, and combined with an optimized number of blades and a reasonable design of the inclination angle, curvature, and angle of attack of the inner and outer edges of the blades, the blades can efficiently perform work on the air during rotation, generating excellent airflow characteristics that balance large air volume and high air pressure.

Description

Technical Field

[0001] This utility model relates to the field of ventilation equipment technology, specifically a mixed-flow ventilation fan. Background Technology

[0002] Exhaust fans, as an important ventilation device, are widely used in various places such as homes, offices, and industrial production to improve indoor air quality and remove moisture, odors, and pollutants. Based on their working principle and structural characteristics, common exhaust fans can be mainly divided into axial flow, centrifugal, and mixed flow types. Axial flow exhaust fans typically have a large air volume but lower air pressure, suitable for short-distance, low-resistance ventilation; centrifugal exhaust fans can generate higher air pressure but relatively smaller air volume, suitable for long-distance ventilation requiring overcoming greater resistance.

[0003] Given the characteristics of the two types of ventilation fans mentioned above, mixed-flow ventilation fans have emerged. Mixed-flow ventilation fans combine the advantages of axial and centrifugal fans, aiming to achieve a better balance between airflow and air pressure, making them more adaptable to various application scenarios. However, despite their balanced design, existing mixed-flow ventilation fans generally still have some technical problems that urgently need to be solved.

[0004] Specifically, existing mixed-flow ventilation fans mainly face the following challenges and drawbacks:

[0005] 1. Many existing mixed-flow ventilation fans fail to fully optimize the airflow path through the fan's interior in their structural design. For example, the way the motor and its supporting structure (such as the motor mount and guide vanes) are positioned may significantly obstruct the airflow, causing eddies, backflows, or sudden changes in cross-section when the airflow enters or exits the fan, resulting in significant energy loss, which is directly manifested as reduced air volume and lower air pressure.

[0006] 2. Existing fan blade designs often fail to adequately consider aerodynamic efficiency, resulting in low work efficiency on air at the same rotational speed, and an inability to effectively convert electrical energy into kinetic and pressure energy. Furthermore, improper design of the structure, quantity, angle, and cross-sectional shape of the guide vanes (or rectifier blades) supporting the motor can not only fail to effectively guide airflow smoothly but also increase airflow resistance and even generate secondary vortices, further reducing airflow and pressure.

[0007] 3. Some existing mixed-flow ventilation fans have simple air inlet structures that fail to effectively pre-guide or rectify the airflow, resulting in significant turbulence when the air enters the fan, which reduces the uniformity and stability of the airflow and thus affects the overall intake efficiency and outlet air volume and pressure of the fan.

[0008] 4. Existing ventilation fans often have a high overall noise level during operation due to the interaction between airflow and the fan blades, guide vanes, and casing, as well as the mechanical noise generated by the high-speed rotation of the motor and fan blades. This affects the user experience, especially in places requiring a quiet environment (such as bedrooms and offices), where this drawback is more pronounced. Therefore, further improvements are necessary. Utility Model Content

[0009] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a mixed-flow ventilation fan that has a more compact structure, can significantly improve air volume and air pressure, reduce noise, improve energy efficiency, optimize structural integration, and improve installation convenience.

[0010] The purpose of this utility model is achieved through the following means: a mixed flow ventilation fan, which includes a base plate and a panel that is fastened to it. The tail end of the base plate is connected to an exhaust pipe. An air inlet is provided on the panel and communicates with the exhaust pipe on the base plate. A motor base is connected to the inner wall of the exhaust pipe through several guide vanes. The motor base is fixed on the central axis of the exhaust pipe by the guide vanes.

[0011] The motor housing contains a drive motor, and the main shaft of the drive motor is equipped with a front fan blade. The front fan blade rotates inside the exhaust pipe, drawing in air from the air inlet and expelling it from the tail of the exhaust pipe.

[0012] Furthermore, the air inlet is flared in shape, wider on the outside and narrower on the inside, and the air inlet is sealed to the end face of the exhaust pipe.

[0013] Furthermore, the air inlet is covered with several concentric guide rings of different diameters. The guide rings are conical rings with a smaller inner diameter and a larger outer diameter. The guide rings are connected to the panel through several radially distributed ribs.

[0014] Furthermore: a connecting frame is provided at the air inlet, and a decorative panel is installed on the end face of the connecting frame. The connecting frame isolates the air inlet duct between the panel and the decorative panel, and the air inlet duct is connected to the air inlet.

[0015] Furthermore, a horn-shaped tube with a larger outer diameter and a smaller inner diameter is provided at the center of the connecting frame.

[0016] Furthermore, the connecting frame extends outward with several docking seats, and correspondingly, the inner end face of the decorative panel is provided with several connecting seats, through which the decorative panel is inserted into the docking seats for connection.

[0017] Furthermore: the front wind blade includes a spherical hub; and a plurality of blades, the blades being mounted on the hub and a cylinder at the lower end of the hub, the blades extending radially on the hub, and the blades gradually decreasing in size from top to bottom in the vertical direction.

[0018] Furthermore, the outer cylindrical surface of the exhaust pipe is provided with a radially protruding connecting bevel, which is connected to the arc transition surface of the outer cylindrical surface of the exhaust pipe.

[0019] Furthermore, the guide vane has an axially extending arc-shaped wing structure.

[0020] Furthermore, the windward end of the guide vane is convex with an arc shape, while the leeward end is pointed.

[0021] The beneficial effects of this utility model are: 1. Simple structure, low production cost, and improved market competitiveness.

[0022] 2. The front fan blades are mixed-flow fan blades. Combined with an optimized number of blades and a reasonable design of the tilt angle, curvature, and angle of attack of the inner and outer edges of the blades, the blades can efficiently perform work on the air during rotation, generating excellent airflow characteristics that balance large air volume and high air pressure. It cleverly integrates the large air volume of an axial fan and the high air pressure of a centrifugal impeller, overcoming the limitations of single-type fan performance in existing technologies. This allows the ventilation fan to maintain ample ventilation volume while overcoming duct resistance and facilitating long-distance exhaust.

[0023] 3. The guide vane adopts an axially extending arc-shaped airfoil structure, with a rounded convex shape at the windward end and a pointed shape at the leeward end. This aerodynamically optimized guide vane structure effectively guides and rectifies the rotating airflow discharged from the front vane, converting the rotational kinetic energy of the airflow into effective pressure energy, thereby significantly increasing pressure and improving the overall static pressure efficiency of the fan. Simultaneously, it reduces airflow turbulence and energy loss, ensuring smooth and stable airflow, and also plays a positive role in reducing noise.

[0024] 4. The air inlet is designed in a trumpet shape with a larger outer diameter and a smaller inner diameter, and its connection with the end face of the exhaust pipe is sealed to ensure smooth airflow, reduce inlet turbulence and resistance, and thus improve air intake efficiency.

[0025] 5. Several concentric guide rings with different diameters are installed at the air inlet, and the guide rings are conical rings with smaller inner diameters and larger outer diameters. This guide ring structure can perform preliminary pre-rectification and guidance on the incoming air, so that the airflow enters the fan more evenly and stably, further reducing airflow resistance and increasing the overall air volume and air pressure.

[0026] 6. A radially protruding connection bevel is provided on the outer cylindrical surface of the exhaust pipe. This design enables the ventilation fan to achieve a simpler, faster, and more secure connection when docking with external pipes, without the need for complex fasteners or additional operations. This significantly improves installation efficiency, ensures the sealing of the connection and the stability of the system, effectively prevents air leakage and loosening, and extends the service life of the equipment. Attached Figure Description

[0027] Figure 1 This is an assembly effect diagram of the first embodiment of this utility model.

[0028] Figure 2 , 3 This is an assembly effect diagram of two embodiments of the present utility model.

[0029] Figure 4 , 5 This is an exploded view of the structure of two embodiments of this utility model.

[0030] Figure 6 This is a schematic diagram of the guide vane structure in this utility model.

[0031] Figure 7 This is a cross-sectional view of the guide vane structure in this utility model.

[0032] Figure 8 This is a cross-sectional view of the front windshield structure in this utility model.

[0033] Explanation of reference numerals in the attached drawings: 1. Base plate; 2. Front panel; 21. Air inlet; 22. Air guide ring; 23. Rib plate; 3. Exhaust pipe; 31. Connecting bevel; 32. Arc transition surface; 4. Air guide vane; 41. Windward end; 42. Leeward end; 5. Motor base; 6. Drive motor; 7. Front fan blade; 71. Fan hub; 72. Blade; 73. Column; 8. Connecting frame; 81. Horn; 82. Docking seat; 9. Decorative panel; 91. Air inlet duct; 92. Connecting seat. Detailed Implementation

[0034] The present invention will be further described in detail below with reference to the accompanying drawings. A mixed-flow ventilation fan includes a base plate 1 and a panel 2 that is fastened to it. An exhaust pipe 3 is connected to the rear end of the base plate 1. An air inlet 21 is provided on the panel 2 and communicates with the exhaust pipe 3 on the base plate 1. A motor base 5 is connected to the inner wall of the exhaust pipe 3 by a plurality of guide vanes 4. The motor base 5 is fixed on the central axis of the exhaust pipe 3 by the guide vanes 4. A drive motor 6 is installed in the motor base 5. A front fan blade 7 is installed on the main shaft of the drive motor 6. The front fan blade 7 rotates inside the exhaust pipe 3, drawing in air from the air inlet 21 and discharging it from the rear end of the exhaust pipe 3.

[0035] In this embodiment: when the drive motor 6 is powered on, its main shaft drives the front fan blade 7 to rotate at high speed. The rotation of the front fan blade 7 creates a negative pressure zone on one side of the air inlet 21 at its front end, thereby drawing outside air into the fan through the air inlet 21 on the panel 2. The drawn-in air enters the exhaust pipe 3 and flows through the rotating front fan blade 7. The front fan blade 7 performs work on the air, giving it kinetic energy and pressure. The guide vane 4 not only serves as a structural component supporting the motor mount 5 and the drive motor 6, but also performs preliminary rectification and guidance on the passing airflow. Finally, the accelerated and pressurized air is discharged from the tail of the exhaust pipe 3, realizing the forced airflow and ventilation function.

[0036] In this embodiment, the intake and exhaust of air are achieved through the basic coordination of the motor, fan blades, and air duct. The "mixed flow" concept it employs provides a foundation for subsequent optimization of air volume and air pressure.

[0037] In one embodiment: the air inlet 21 is flared in shape, with the outer part being larger than the inner part, and the air inlet 21 is sealed and connected to the end face of the exhaust pipe 3.

[0038] In this embodiment, the horn-shaped air inlet 21 effectively guides airflow smoothly into the fan. As air flows through the horn-shaped inlet, its velocity gradually increases, while reducing turbulence and energy loss at the inlet. The sealed connection with the exhaust pipe 3 ensures the integrity of the airflow path, preventing air backflow or leakage, and allowing all intake air to effectively pass through the core working area of ​​the fan.

[0039] The optimized geometry of the airflow inlet effectively reduces intake resistance, minimizes airflow turbulence, and improves intake efficiency and overall fan airflow. Simultaneously, the sealed connection ensures system airtightness, further enhancing air pressure and energy efficiency, and helping to reduce noise caused by air leakage.

[0040] In one embodiment: the air inlet 21 is covered with a plurality of concentric guide rings 22 of different diameters. The guide rings 22 are conical rings with smaller inner diameters and larger outer diameters. The guide rings 22 are connected to the panel 2 by a plurality of radially distributed ribs 23.

[0041] These concentric tapered air guide rings 22 pre-guide and pre-rectify the air before it enters the air inlet. As the air flows through the air guide rings, the tapered structure and concentric distribution of the rings can guide the dispersed air, which may have initial swirl, into a smoother and more uniform axial airflow, creating favorable airflow conditions for the efficient operation of the subsequent front vane 7.

[0042] This structure further optimizes the intake air quality, significantly reducing turbulence before the airflow enters the fan blades and lowering energy loss. This not only helps increase the actual airflow and air pressure of the fan, but also effectively reduces noise caused by airflow turbulence, improving the fan's operational stability and energy efficiency.

[0043] In one embodiment: a connecting frame 8 is provided at the air inlet 21, and a decorative panel 9 is installed on the end face of the connecting frame 8. The connecting frame 8 isolates an air inlet duct 91 between the panel 2 and the decorative panel 9, and the air inlet duct 91 is connected to the air inlet 21.

[0044] In this embodiment, an independent air intake duct 91 is constructed outside the air intake 21. External air first enters the air intake duct 91 through the reserved gaps or holes in the decorative panel 9, and is then guided to the air intake 21 along this channel, while the decorative panel 9 serves both aesthetic and protective functions.

[0045] This design provides a longer, controlled air intake path, which facilitates further buffering and rectification of airflow, reduces interference from the external environment, and helps reduce operating noise. At the same time, the decorative panel 9 enhances the overall aesthetics of the product and also protects the internal components. This structure offers more flexible appearance design and installation options for the product.

[0046] In one embodiment, a horn tube 81 with a larger outer diameter and a smaller inner diameter is provided at the center of the connecting frame 8.

[0047] In this embodiment, by setting a horn 81 at the center of the connecting frame 8, the air undergoes a secondary horn-shaped contraction before entering the main air inlet 21. This is similar to a two-stage air intake pretreatment, allowing the airflow to be further smoothly accelerated and guided before entering the core fan area. This helps to maximize air intake efficiency, thereby improving the overall performance of the fan (air volume and air pressure) and reducing noise.

[0048] In one embodiment: a plurality of docking seats 82 are provided on the connecting frame 8 extending outward, and correspondingly, a plurality of connecting seats 92 are provided on the inner end face of the decorative panel 9, and the decorative panel 9 is inserted into the docking seat 82 and connected thereto through the connecting seat 92.

[0049] In this embodiment, the quick positioning and reliable connection of the decorative panel are achieved through the plug-in engagement of the connecting seat 92 and the mating seat 82. This also greatly improves the ease of installation. Users can easily install or remove the decorative panel, which facilitates daily cleaning and maintenance, such as cleaning dust from the air inlet and replacing the decorative panel to suit different decorating styles.

[0050] In one embodiment: the front wind blade 7 includes a spherical hub 71; and a plurality of blades 72, the blades 72 being disposed on the hub 71 and a cylinder 73 at the lower end of the hub 71, the blades 72 extending radially on the hub 71, and the blades 72 gradually decreasing in size from top to bottom in the vertical direction.

[0051] In this embodiment: the spherical hub 71 and the lower cylinder 73: this combined structure provides a stable mounting base for the blade 72 and optimizes airflow at the blade root, reducing eddies and separation. The spherical design helps guide airflow smoothly into the blade.

[0052] Meanwhile, the radial and vertical dimensions of blade 72 gradually decrease: this special blade geometry allows the blade to generate not only axial thrust, similar to an axial fan, but also radial centrifugal force, similar to a centrifugal fan, during rotation. The gradual decrease in blade size from top to bottom likely indicates superior aerodynamic performance. Furthermore, the angle of attack and radii along both the radial and axial directions are optimized to adapt to varying airflow speeds and pressure distributions at different locations, achieving efficient energy conversion across the entire blade surface. This embodies the "mixed flow" principle, enabling the blade to simultaneously handle both high airflow and high air pressure output while effectively reducing operating noise.

[0053] In one embodiment: a radially protruding connecting bevel 31 is provided on the outer cylindrical surface of the exhaust pipe 3, and the connecting bevel 31 is connected to the arc transition surface 32 of the outer cylindrical surface of the exhaust pipe 3.

[0054] In this embodiment, the connecting bevel 31 forms a positioning and socketing structural feature. When the ventilation fan needs to be connected to external ducts, such as ventilation ducts or smoke exhaust pipes, the bevel can easily engage, connect, or act as a limiter with the interface of the external duct. The arc transition surface 32 ensures a smooth transition at the connection, which is beneficial for insertion and sealing.

[0055] This design simplifies the on-site installation process, making connections faster and more secure, and effectively ensuring the seal at the joints, reducing air leakage and improving the efficiency and stability of the entire ventilation system. At the same time, it reduces the need for additional connectors, lowering installation costs.

[0056] In one example, the guide vane 4 is an axially extending arc-shaped airfoil structure. While performing work on the air, the front vane 7 imparts rotational kinetic energy to the airflow. The axially extending arc-shaped airfoil 4 effectively converts the rotational kinetic energy of the airflow into static pressure energy as the airflow passes through, thereby achieving airflow pressurization. Its arc-shaped airfoil structure is aerodynamically optimized to achieve maximum rectification and pressurization with minimal energy loss.

[0057] Meanwhile, this guide vane design is a key auxiliary component for achieving high air pressure. It efficiently converts the rotational kinetic energy of the airflow into useful static pressure energy, significantly improving the fan's static pressure performance. Simultaneously, through rectification, it reduces airflow eddies and turbulence, helping to lower exhaust noise and improve airflow uniformity.

[0058] In one embodiment: the windward end of the guide vane 4 is convex with an arc shape, and the leeward end 42 is pointed.

[0059] This airfoil design is similar to the cross-section of an aircraft wing or a high-efficiency wind turbine blade. The rounded, convex leading edge at the windward end allows airflow to be smoothly separated and adhered to the surface of the guide vanes, reducing impact and turbulence. The pointed leeward end ensures that airflow leaves the blade surface cleanly and quickly, preventing vortex shedding and thus minimizing airflow drag and noise.

[0060] This structure further optimizes the aerodynamic performance of the guide vanes. It makes the guide vanes more efficient and reduces energy loss when guiding and pressurizing airflow. This refined blade design has a significant effect on reducing fan operating noise, while further improving pressurization efficiency and overall energy efficiency.

[0061] In summary, the mixed-flow ventilation fan provided by this utility model works by using a set of highly integrated and carefully designed components to efficiently achieve forced air circulation and ventilation.

[0062] First, outside air is guided and initially rectified through an optimized air inlet, ensuring that the airflow enters the fan smoothly with minimal resistance and turbulence.

[0063] Next, the core front fan blade 7 rotates at high speed driven by the drive motor 6. This mixed-flow fan blade design endows the airflow with the dual characteristics of large axial air volume and high radial air pressure. It effectively converts electrical energy into the kinetic and pressure energy of the airflow, overcoming the single performance bottleneck of traditional axial or centrifugal fans.

[0064] Subsequently, the airflow enters the guide vane 4 area. These guide vanes not only support the motor mount 5, but are themselves aerodynamically optimized axially extended arc-shaped airfoil structures, especially their rounded convex front end and pointed leeward end. Their core function is to efficiently convert the rotational kinetic energy imparted to the airflow by the front vane 7 into effective static pressure energy, thereby achieving "pressurization" of the airflow. At the same time, the guide vanes can further rectify the airflow, eliminate rotational components, and make the airflow smoother and more uniform.

[0065] Finally, the pressurized and rectified airflow is discharged from the tail of the exhaust pipe 3. The design of the radially protruding connecting bevel 31 and the arc transition surface 32 on the exhaust pipe 3 greatly simplifies the connection process between the ventilation fan and the external pipeline, ensures the firmness and airtightness of the connection, and improves the installation efficiency and system stability. Therefore, it can be widely used.

[0066] In summary, this invention, through comprehensive optimization and innovative integration of the air intake path, core mixing fan blades, high-efficiency pressurized guide vanes, and convenient duct connection methods, forms a collaborative and efficient working system. This system significantly improves the airflow and air pressure performance of the ventilation fan, while effectively reducing operating noise, increasing energy utilization efficiency, and greatly enhancing the ease of installation and maintenance. Thus, it completely solves many shortcomings of existing mixing fan products in terms of performance and user experience, providing a technologically advanced and highly practical mixing fan product.

[0067] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model.

Claims

1. A mixed-flow ventilation fan, comprising a base plate (1) and a panel (2) fastened thereto, wherein an exhaust pipe (3) is connected to the rear end of the base plate (1), and an air inlet (21) is provided on the panel (2) and communicates with the exhaust pipe (3) on the base plate (1), characterized in that: The inner wall of the exhaust pipe (3) is connected to a motor base (5) by a number of guide vanes (4), and the motor base (5) is fixed on the central axis of the exhaust pipe (3) by the guide vanes (4); The motor mount (5) is equipped with a drive motor (6), and a front fan blade (7) is mounted on the main shaft of the drive motor (6). The front fan blade (7) rotates inside the exhaust pipe (3), drawing in air from the air inlet (21) and discharging it from the tail of the exhaust pipe (3).

2. A mixed-flow ventilation fan according to claim 1, characterized in that: The air inlet (21) is shaped like a trumpet with a larger outer diameter and a smaller inner diameter, and the air inlet (21) is sealed and connected to the end face of the exhaust pipe (3).

3. A mixed-flow ventilation fan according to claim 1, characterized in that: The air inlet (21) is covered with several concentric guide rings (22) of different diameters. The guide rings (22) are conical rings with smaller inner diameters and larger outer diameters. The guide rings (22) are connected to the panel (2) by several radially distributed ribs (23).

4. A mixed-flow ventilation fan according to claim 1, characterized in that: A connecting frame (8) is provided at the air inlet (21). A decorative panel (9) is installed on the end face of the connecting frame (8). The connecting frame (8) isolates the air inlet channel (91) between the panel (2) and the decorative panel (9). The air inlet channel (91) is connected to the air inlet (21).

5. A mixed-flow ventilation fan according to claim 4, characterized in that: A horn tube (81) with a larger outer diameter and a smaller inner diameter is provided at the center of the connecting frame (8).

6. A mixed-flow ventilation fan according to claim 4, characterized in that: The connecting frame (8) has several docking seats (82) extending outward. Correspondingly, the inner end face of the decorative panel (9) has several connecting seats (92). The decorative panel (9) is inserted into the docking seat (82) and connected to it through the connecting seat (92).

7. A mixed-flow ventilation fan according to claim 1, characterized in that: The front wind vane (7) includes a spherical fan hub (71) and a plurality of blades (72), the blades (72) being mounted on the fan hub (71) and a cylinder (73) at the lower end of the fan hub (71), the blades (72) extending radially on the fan hub (71), and the dimensions of the blades (72) gradually decreasing from top to bottom in the vertical direction.

8. A mixed-flow ventilation fan according to claim 1, characterized in that: The outer cylindrical surface of the exhaust pipe (3) is provided with a radially protruding connecting bevel (31), which is connected to the arc transition surface (32) of the outer cylindrical surface of the exhaust pipe (3).

9. A mixed-flow ventilation fan according to claim 1, characterized in that: The guide vane (4) has an axially extended arc-shaped wing structure.

10. A mixed-flow ventilation fan according to any one of claims 1 or 9, characterized in that: The windward end (41) of the wind guide vane (4) is convex in an arc shape, and the leeward end (42) is pointed in a sharp angle shape.

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