Axial flow fan

Abstract

An axial flow fan comprises a cylindrical machine shell (8), a motor (2) is placed in the machine shell, a front end cover of the motor is connected with a supporting disc (5), a plurality of battens (4) are symmetrically connected to the outer circle of the supporting disc, the outer ends of the battens are connected to the inner wall of a shell, a housing (3) is arranged on the motor in a sleeved mode, the housing is connected with the supporting disc, and the outer diameter of the housing is equal to the diameter of a hub (7) of an impeller. The left end of the housing is closed, and the closed end is hemispherical. The fan has the advantages that the battens are symmetrically distributed in the machine shell, airflow can evenly flow at an inlet of the impeller, the pneumatic performance of the fan is improved, the connecting motor is fixed to the machine shell through the battens on the supporting disc, stress of the connecting motor is even, and when the fan rotates, vibration is not prone to occurring; the battens can be arranged at a certain deflection angle, so that the total pressure of the ventilator level can be improved; the motor is sleeved with the housing, so that random disturbance of the motor to airflow can be avoided; the closed end of the cover shell is hemispherical, so that sudden contraction of air inlet can be avoided.

Description

Technical Field

[0001] This utility model relates to an axial flow fan. Background Technology

[0002] Axial flow fans typically consist of a cylindrical casing, impeller, and motor. The impeller is connected to the motor, which is housed within the casing. The connection method involves a V-shaped bracket inside the casing, with one end of each bracket leg fixed to the inner wall of the casing and the other end connected to the motor's base. This connection structure is simple and easy to manufacture. However, the brackets cannot be symmetrically distributed within the casing, resulting in uneven airflow at the impeller inlet. Irregular surfaces such as the motor housing's cooling fins and junction box can also cause random disturbances to the airflow, leading to a decrease in the fan's aerodynamic performance. Furthermore, the fan is prone to vibration during rotation. Utility Model Content

[0003] To solve the above-mentioned technical problems, this utility model designs an axial flow fan, which enables the airflow to flow evenly at the impeller inlet, improves the aerodynamic performance of the fan, and reduces the vibration when the fan rotates.

[0004] The technical solution adopted by this utility model is an axial flow fan, which includes a cylindrical casing 8, a motor 2 placed in the casing, and the motor shaft connected to an impeller 9. The feature is that the front end cover of the motor is connected to a support plate 5, and multiple strips 4 are symmetrically connected on the outer circle of the support plate. The number of strips is less than the number of blades 6 of the impeller. The outer ends of the strips are connected to the inner wall of the casing. A cover 3 is fitted on the motor and connected to the support plate. The outer diameter of the cover is equal to the diameter of the impeller hub 7. The left end of the cover is closed and the closed end is hemispherical.

[0005] Its beneficial effects are as follows: the symmetrical distribution of the strips inside the casing allows for uniform airflow at the impeller inlet, improving the aerodynamic performance of the fan; the motor is fixed to the casing on the support plate via multiple strips, resulting in uniform force distribution and reducing vibration during fan rotation; the strips can be set at a certain deflection angle, which helps to improve the total pressure of the fan stage; the motor is covered with a casing to prevent random disturbances to the airflow; and the closed end of the casing is hemispherical to prevent sudden contraction of the air intake. Attached Figure Description

[0006] Figure 1 This is a schematic diagram of the structure of this utility model.

[0007] Figure 2 for Figure 1 A-direction view.

[0008] Figure 3 for Figure 1 View B.

[0009] Attached diagram symbols: 1-Flare mouth, 2-Motor, 3-Cover, 4-Strip, 5-Support plate, 6-Blade, 7-Hub, 8-Casing, 9-Impeller, 10-Base. Detailed Implementation

[0010] An axial flow fan includes a cylindrical casing 8, which is fixedly placed on a base 10. A motor 2 is placed inside the casing, and the motor shaft is connected to an impeller 9. The motor's front end cover is connected to a support plate 5. Multiple strips 4 are symmetrically connected to the outer circle of the support plate. The number of strips 4 is less than the number of blades 6 of the impeller 9. For example, if the number of blades is 10 to 15, the number of strips is 4 to 8. The outer ends of the strips 4 are connected to the inner wall of the casing 8. A cover 3 is fitted onto the motor. The support plate has a stop extending to the left. The cover 3 is connected to the stop of the support plate 5. The outer diameter of the cover and the diameter of the support plate are equal to the diameter of the impeller hub 7. The left end of the cover is closed, and the closed end is hemispherical.

[0011] The symmetrically distributed strips inside the casing allow for uniform airflow at the impeller inlet, improving the fan's aerodynamic performance. The motor is fixed to the casing via multiple strips on the support plate, ensuring even stress distribution and minimizing vibration during fan rotation. A cover is fitted over the motor to prevent irregular surfaces such as the motor housing's cooling fins and junction box from disturbing the airflow. The hemispherical closed end of the cover prevents sudden air intake contraction.

[0012] To achieve better air intake, the left end of the casing is a flared opening 1, with a rounded transition between the flared opening and the cylinder.

[0013] The strip has a certain deflection angle, that is, the surface of the strip rotates around the diameter line of the casing by a certain angle. The deflection angle can be selected between 15 degrees and 60 degrees, preferably 30 degrees. Its function is to make the airflow generate negative swirl at the impeller inlet, so as to improve the total pressure of the fan stage.

Claims

1. An axial flow fan, comprising a cylindrical casing (8), in which a motor (2) is housed, the motor shaft being connected to an impeller (9), characterized in that, The front cover of the motor is connected to the support plate (5). Multiple strips (4) are symmetrically connected on the outer circle of the support plate. The number of strips is less than the number of blades (6) of the impeller. The outer ends of the strips are connected to the inner wall of the housing. A cover (3) is fitted on the motor. The cover is connected to the support plate. The outer diameter of the cover is equal to the diameter of the impeller hub (7). The left end of the cover is closed, and the closed end is hemispherical.

2. The axial flow fan according to claim 1, characterized in that, The left end of the casing is a flared mouth (1), and there is a rounded transition between the flared mouth and the cylindrical part.

3. The axial flow fan according to claim 1 or 2, characterized in that, The strip has a certain deflection angle of 30 degrees.

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