A mixed flow fan

Abstract

The utility model relates to the pumping device or system technical field of elastic fluid discloses a mixed flow fan, include: casing, motor, impeller, set up air flow channel between casing and motor, impeller and motor shaft fixed connection, open first air hole in the thrust bearing, casing open second air hole, impeller rotates, produces gas flow, gas flows to air outlet from air flow channel, can take away the heat on the surface of motor, part of airflow enters motor inside from first air hole, then flows from second air hole, can take away the heat generated in the motor inside and bearing, solved the prior art in the pneumatic heat dissipation mode only can take away the heat on the surface of motor, and the heat in the motor cannot be taken away directly by the airflow, thereby leading to the local temperature rise of motor inside and bearing, influence the life of motor and bearing problem.

Description

Technical Field

[0001] This utility model relates to the technical field of pumping devices or systems for elastic fluids, and in particular to a mixed-flow fan. Background Technology

[0002] Axial flow fans and centrifugal fans are widely used in industrial ventilation, energy equipment, aerospace, and other fields, and are the two most common types of fans in the industrial sector. However, they each have performance limitations: axial flow fans typically have the advantage of high flow rate, but their single-stage pressure is relatively low; centrifugal fans can provide higher pressure, but their flow range is limited. In applications requiring both high flow rate and high pressure, multi-stage fans are often connected in series or other complex structures are used, resulting in a large system size and reduced efficiency. Mixed-flow fans theoretically combine the advantages of both. Their core function is to transport gas (air or flue gas) and provide pressure during the transport process. Mixed-flow fans combine the characteristics of axial flow fans and centrifugal fans. Their core working principle is that a motor drives an impeller to rotate at high speed, enabling directional gas flow.

[0003] Mixed-flow fans generate a significant amount of heat during high-speed operation, primarily from the motor and bearings. Ineffective heat dissipation during operation will negatively impact the overall lifespan of the fan, especially the motor and bearings. Currently, the most common heat dissipation method for mixed-flow fans is aerodynamic cooling. This method utilizes the airflow generated by the fan itself to cool it. The high-speed airflow flows directly over the motor housing, rapidly carrying away heat. This is the most direct and efficient cooling method for mixed-flow fans.

[0004] This pneumatic cooling method can directly remove heat from the surface of the motor. However, since the inside of the motor is enclosed, the heat inside the motor cannot be directly removed by the airflow, which may cause the temperature inside the motor and bearings to rise locally, thus affecting the lifespan of the motor and bearings. Utility Model Content

[0005] In view of this, the main purpose of this utility model is to provide a mixed-flow fan that can solve the problem that in the prior art, the pneumatic cooling method can only remove heat from the surface of the motor, while the inside of the motor is closed and the heat inside the motor cannot be directly removed by the airflow, which may lead to local temperature rise inside the motor and bearings, thereby affecting the life of the motor and bearings.

[0006] To achieve the above objectives, the technical solution of this utility model is implemented as follows: A mixed-flow fan includes: a housing, a motor, and an impeller, wherein an airflow channel is provided between the housing and the motor; and the impeller is fixedly connected to the motor shaft. The motor also includes: a motor housing, a stator, a rotor, a radial bearing, and a thrust bearing. The stator is fixedly connected inside the motor housing. The motor shaft is rotatably connected to the motor housing through the radial bearing and the thrust bearing. The rotor is fixedly connected to the motor shaft. The thrust bearing has a first vent hole, and the housing has a second vent hole; In a preferred embodiment, the radial bearing and the thrust bearing are air-floating pressure bearings.

[0007] In a preferred embodiment, the rotor is fixedly connected inside the motor shaft.

[0008] In a preferred embodiment, the motor shaft includes: an impeller shaft, an intermediate shaft, and a third shaft. The intermediate shaft is hollow, the rotor is fixedly connected inside the intermediate shaft, the impeller shaft is fixedly connected to one end of the intermediate shaft, and the third shaft is fixedly connected to the other end of the intermediate shaft. In a preferred embodiment, the impeller is fixedly connected to the impeller shaft, and the thrust disc of the thrust bearing is fixedly connected to the third shaft. In a preferred embodiment, the intermediate shaft is provided with a limiting protrusion, which can limit the position of the rotor.

[0009] In a preferred embodiment, an adjustment shim is provided between the rotor and the third shaft.

[0010] In a preferred embodiment, the impeller shaft and the intermediate shaft are connected by threads, the intermediate shaft and the third shaft are connected by threads, and the threads of the impeller shaft and the third shaft have opposite directions.

[0011] In a preferred embodiment, both the impeller shaft and the third shaft are hollow, and the impeller shaft and the third shaft are provided with vent holes.

[0012] The mixed-flow fan of this utility model has the following beneficial effects: The mixed-flow fan includes a housing, a motor, an impeller, and an airflow channel between the housing and the motor. The impeller is fixedly connected to the motor shaft. The motor also includes a motor housing, a stator, a rotor, a radial bearing, and a thrust bearing. The stator is fixedly connected inside the motor housing. The motor shaft is rotatably connected to the motor housing through the radial bearing and the thrust bearing. The rotor is fixedly connected to the motor shaft. A first vent hole is provided in the thrust bearing, and a second vent hole is provided in the housing.

[0013] The impeller of the mixed-flow fan rotates, generating airflow. The air flows from the airflow channel to the air outlet, which can carry away the heat from the surface of the motor. Some of the airflow enters the motor from the first vent and then flows out from the second vent, which can carry away the heat generated inside the motor and the bearings.

[0014] This invention solves the problem that in existing technologies, pneumatic cooling methods can only remove heat from the surface of the motor, while the heat inside the motor cannot be directly removed by the airflow, leading to localized temperature increases inside the motor and bearings, which in turn affects the lifespan of the motor and bearings. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art 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.

[0016] Figure 1 This is a schematic diagram of a mixed-flow fan structure according to one embodiment of the present disclosure; Figure 2 This is a schematic diagram of airflow in a mixed-flow fan according to one embodiment of the present disclosure; Figure 3 This is a schematic diagram of a motor structure according to one embodiment of the present disclosure; Figure 4 This is a schematic diagram of a motor shaft structure according to one embodiment of the present disclosure; Figure 5 This is a cross-sectional view of a motor shaft according to one embodiment of the present disclosure; Figure 6 This is a schematic diagram illustrating the calculation of the adjustment shim size according to one embodiment of the present disclosure.

[0017] [Explanation of Key Component Symbols] 1. Housing; 2. Motor; 21. Motor housing; 22. Stator; 23. Rotor; 24. Motor shaft; 25. Radial bearing; 26. Thrust bearing; 211. Second vent; 241. Impeller shaft; 242. Intermediate shaft; 243. Third shaft; 244. Limiting protrusion; 245. Adjusting shim; 246. Vent hole; 261. First vent; 262. Front thrust bearing; 263. Thrust plate; 264. Rear thrust bearing; 3. Impeller; 5. Airflow channel; 6. Air inlet; 7. Air outlet. Detailed Implementation

[0018] The mixed-flow fan of this utility model will be further described in detail below with reference to the accompanying drawings and embodiments.

[0019] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0020] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0021] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented, for example, in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0022] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0023] according to Figures 1-6As shown, this application discloses a mixed-flow fan, comprising: a housing 1, a motor 2, and an impeller 3. An airflow channel 5 is provided between the housing 1 and the motor 2, and the impeller 3 is fixedly connected to the motor shaft 24. The motor 2 of the mixed-flow fan drives the impeller 3 to rotate, generating airflow, causing air to enter from the air inlet 6, flow through the airflow channel 5 to the air outlet 7, and the airflow direction is as follows. Figure 2 As shown by the hollow arrow, the flowing air can carry away the heat from the surface of motor 2.

[0024] The motor 2 also includes: a motor housing 21, a stator 22, a rotor 23, a radial bearing 25, and a thrust bearing 26. The stator 22 is fixedly connected inside the motor housing 21. The motor shaft 24 passes through a hole in the center of the stator 22 and is rotatably connected to the motor housing 21 via the radial bearing 25 and the thrust bearing 26. The rotor 23 is fixedly connected to the motor shaft 24 and is located at the center of the stator 22. The thrust bearing includes: a front thrust bearing 262, a thrust plate 263, and a rear thrust bearing 264. The front thrust bearing 262 and the rear thrust bearing 264 are fixedly connected to the motor housing 21. The thrust plate 263 is located between the front thrust bearing 262 and the rear thrust bearing 264 and is fixedly connected to the motor shaft 24. The impeller 3 is located at the air inlet 6 of the fan, and the thrust bearing 26 is located at the air outlet 7 of the fan.

[0025] To facilitate heat dissipation inside the motor, the thrust bearing 26 has a first vent 261, and the housing has a second vent 211. As the airflow velocity decreases and the pressure increases after passing through the airflow channel 5, the pressure at the air outlet 7 of the mixed-flow fan is greater than the pressure at the air inlet 6. Under this pressure difference, some airflow enters the motor through the first vent 261 and then flows out through the second vent 211, merging with the main airflow generated by the mixed-flow fan. The airflow direction is as follows: Figure 2 As shown by the solid arrow, airflow passes through the inside of the motor, carrying away the heat generated inside the motor and bearings. This solves the problem in existing technologies where pneumatic cooling methods can only remove heat from the surface of the motor, while the heat inside the motor cannot be directly removed by the airflow, leading to localized temperature increases inside the motor and bearings, thus affecting the lifespan of the motor and bearings.

[0026] Because traditional bearings (such as rolling bearings or traditional sliding bearings) experience severe friction and wear at high speeds, requiring complex lubrication and cooling systems, resulting in high maintenance costs and limiting the improvement of rotational speed and lifespan; therefore, radial bearing 25 and thrust bearing 26 are air-floating pressure bearings. When motor 2 rotates at high speed, airflow through radial bearing 25 and thrust bearing 26 generates a dynamic pressure effect, forming a stable air film that supports motor shaft 24; To ensure unobstructed airflow within the motor, the rotor 23 is fixedly connected inside the motor shaft 24. The rotor 23 and the motor shaft 24 can be fixed using methods such as interference fit or a key.

[0027] To facilitate disassembly, maintenance, or replacement of the rotor 23, the motor shaft 24 includes an impeller shaft 241, an intermediate shaft 242, and a third shaft 243. The intermediate shaft 242 is hollow, and the rotor 23 is fixedly connected inside the intermediate shaft 242. The impeller shaft 241 is fixedly connected to one end of the intermediate shaft 242, and the third shaft 243 is fixedly connected to the other end of the intermediate shaft 242. When the rotor 23 needs maintenance or replacement, the impeller shaft 241 and the third shaft 243 are disassembled, and the rotor 23 can be removed from the intermediate shaft 242 by applying pressure or tapping.

[0028] Impeller 3 is fixedly connected to impeller shaft 241, and thrust bearing 26 thrust plate 263 is fixedly connected to third shaft 243.

[0029] To facilitate limiting the installation position of the rotor 23, the intermediate shaft 242 is provided with a limiting protrusion 244, which can limit the position of the rotor 23.

[0030] To accommodate the machining tolerances of rotor 23 and third shaft 243, an adjusting shim 245 is provided between rotor 23 and third shaft 243. The thickness of the adjusting shim can be determined according to the actual dimensions of the machined part, such as... Figure 6 As shown, the thickness of the adjusting shim 245 is calculated by subtracting the length L2 of the rotor from the length L1 from the protrusion 244 on the intermediate shaft 243 to the edge of the intermediate shaft 243, and then subtracting the length L3 of the mating between the third shaft 243 and the intermediate shaft 242. After the part is machined, the thickness of the adjusting shim can be calculated by measuring the lengths L1, L2, and L3. A single shim can be used, machined to achieve the desired thickness, or multiple shims can be stacked to achieve the required thickness.

[0031] The impeller shaft 241 and the intermediate shaft 242 are connected by threads, and the intermediate shaft 242 and the third shaft 243 are also connected by threads. The threads of the impeller shaft 241 and the third shaft 243 have opposite directions of rotation. If viewed from the air inlet 6 of the mixed-flow fan, when the motor shaft rotates clockwise, the thread of the impeller shaft 241 is left-handed, and the thread of the third shaft 243 is right-handed; if viewed from the air inlet 6 of the mixed-flow fan, when the motor shaft rotates counterclockwise, the thread of the impeller shaft 241 is right-handed, and the thread of the third shaft 243 is left-handed.

[0032] Both the impeller shaft 241 and the third shaft 243 are hollow, and vent holes 246 are provided on the impeller shaft 241 and the third shaft 243. When the motor 2 is working and the temperature rises, the expanding gas can flow out from the vent holes 246, which is beneficial to the gas pressure balance and promotes the air flow around the rotor 23, thereby reducing the temperature near the rotor 23. The above description is merely a preferred embodiment of the present utility model and is not intended to limit the scope of protection of the present utility model.

Claims

1. A mixed-flow fan, characterized in that, include: The device comprises a housing (1), a motor (2), and an impeller (3), with an airflow channel (5) provided between the housing (1) and the motor (2); the impeller (3) is fixedly connected to the motor shaft (24). The motor (2) further includes: a motor housing (21), a stator (22), a rotor (23), a radial bearing (25), and a thrust bearing (26). The stator (22) is fixedly connected inside the motor housing (21). The motor shaft (24) is rotatably connected to the motor housing (21) through the radial bearing (25) and the thrust bearing (26). The rotor (23) is fixedly connected to the motor shaft (24). The thrust bearing (26) has a first vent hole (261), and the housing has a second vent hole (211).

2. The mixed-flow fan according to claim 1, characterized in that, The radial bearing (25) and thrust bearing (26) are air-floating pressure bearings.

3. The mixed-flow fan according to claim 1, characterized in that, The rotor (23) is fixedly connected inside the motor shaft (24).

4. The mixed-flow fan according to claim 3, characterized in that, The motor shaft (24) includes: an impeller shaft (241), an intermediate shaft (242) and a third shaft (243). The intermediate shaft (242) is hollow. The rotor (23) is fixedly connected inside the intermediate shaft (242). The impeller shaft (241) is fixedly connected to one end of the intermediate shaft (242), and the third shaft (243) is fixedly connected to the other end of the intermediate shaft (242).

5. The mixed-flow fan according to claim 4, characterized in that, The impeller (3) is fixedly connected to the impeller shaft (241), and the thrust plate (263) of the thrust bearing (26) is fixedly connected to the third shaft (243).

6. The mixed-flow fan according to claim 4, characterized in that, The intermediate shaft (242) is provided with a limiting protrusion (244), which can limit the position of the rotor (23).

7. The mixed-flow fan according to claim 6, characterized in that, An adjusting shim (245) is provided between the rotor (23) and the third shaft (243).

8. The mixed-flow fan according to claim 4, characterized in that, The impeller shaft (241) and the intermediate shaft (242) are connected by threads, and the intermediate shaft (242) and the third shaft (243) are connected by threads. The threads of the impeller shaft (241) and the third shaft (243) are in opposite directions.

9. The mixed-flow fan according to claim 4, characterized in that, Both the impeller shaft (241) and the third shaft (243) are hollow, and the impeller shaft (241) and the third shaft (243) are provided with vent holes (246).

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