Small axial flow fan

Abstract

The invention provides a small axial flow fan, and belongs to the technical field of fans, the small axial flow fan specifically comprises a shell, a rotor, a stator, a shaft, a shaft sleeve, a positioning sleeve and a circuit board assembly, the shaft is sleeved with a first bearing, a second bearing and the positioning sleeve, the positioning sleeve is located in the middle area of the shaft, a spring is arranged on the inner side of the positioning sleeve, and the spring sleeves the shaft; the first bearing and the second bearing are located on the two sides of the positioning sleeve respectively, the first bearing, the second bearing and the positioning sleeve are installed in the shaft sleeve, the stator is arranged outside the shaft sleeve, the rotor is installed on the outer side of the stator through a bearing support, and the shaft end conducts axial positioning on the rotor through a nut. The circuit board assembly is fixed in the metal shielding cavity, and the winding start and end of the stator are welded at the fixed position of the circuit board assembly. By means of the treatment scheme, the small axial flow fan can provide high rotating speed and large-air-volume air pressure in a complex environment while the small size is kept.

Description

TECHNICAL FIELD

[0001] The present application relates to the fan technical field, especially to a small axial flow fan. BACKGROUND

[0002] With the accelerated development of weapons and equipment, the power of components requiring heat dissipation increases year by year, and due to the installation space of air cooling equipment, the fan is required to perform rapid air cooling heat dissipation in a small space under high wind resistance. In view of the above requirements, a small high-speed axial flow fan with high speed and large air volume and wind pressure is provided. SUMMARY

[0003] Therefore, the present application provides a small axial flow fan, which at least partially solves the problem that the small volume direct current axial flow fan cannot generate large air volume and wind pressure in the prior art.

[0004] The present application provides a small axial flow fan, which comprises a shell, a rotor, a stator, a shaft, a shaft sleeve, a positioning sleeve and a circuit board assembly. The first bearing, the second bearing and the positioning sleeve are sleeved on the shaft, the positioning sleeve is located in the middle region of the shaft, the inner side of the positioning sleeve is provided with a spring, the spring is sleeved on the shaft, the first bearing and the second bearing are respectively located on the two sides of the positioning sleeve, the first bearing, the second bearing and the positioning sleeve are installed in the interior of the shaft sleeve, the exterior of the shaft sleeve is provided with the stator, the rotor is supported and installed on the exterior of the stator through the bearing, the shaft end is axially positioned to the rotor through the nut, the rear end of the shell is provided with a metal shielding cavity, the circuit board assembly is fixed in the metal shielding cavity, and the winding tail of the stator is welded at the fixed position of the circuit board assembly.

[0005] According to a specific implementation manner of the present application, the frame of the shell is provided with a guide vane, and the rotation direction of the guide vane is opposite to the rotation direction of the rotor.

[0006] According to a specific implementation manner of the present application, the guide vane is provided with a groove for leading out a wire.

[0007] According to a specific implementation manner of the present application, the fan blades of the rotor are prepared and formed in a manner of retaining the maximum outer diameter size and combining the overlapping of the fan blade projection surfaces.

[0008] According to a specific implementation manner of the present application, the bottom wall in the metal shielding cavity is provided with a boss, and the boss limits the circuit board assembly.

[0009] According to a specific implementation manner of the present application, the circuit board assembly is filled in the metal shielding cavity through the filling glue.

[0010] According to a specific implementation manner of the present application, the second bearing is arranged close to the nut, and a hole is arranged between the second bearing and the positioning sleeve.

[0011] According to a specific implementation manner of the embodiment of the present application, the first gasket is arranged between the hole collar and the positioning sleeve, and the second gasket is arranged between the hole collar and the second bearing.

[0012] According to a specific implementation manner of the embodiment of the present application, the shell and the shaft sleeve are integrally pressure die formed, and the rotor, the shaft and the rotor sleeve are integrally pressure die formed.

[0013] According to a specific implementation manner of the embodiment of the present application, the shaft sleeve and the stator are limited through the key groove.

[0014] Beneficial effects: The small axial flow fan in the embodiment of the present application, the axial flow fan fixes a series of rotating structural members such as the rotor, the bearing and the spring coaxially through the shaft sleeve, provides sufficient bearing pre-tightening force and reduces the rotational inertia, ensures that the rotor rotates stably and reduces self-vibration when the fan reaches 30000 rpm rotating speed. The integrally pressure die formed design of the shell and the shaft sleeve effectively improves the rigidity and coaxiality of the overall structure, reduces the influence of assembly error on the performance of the fan; the integrally pressure die formed of the rotor, the shaft and the rotor sleeve further optimizes the dynamic balance performance of the rotor, reduces the noise and energy loss in high-speed rotation. In order to meet the electromagnetic capacity requirement under the airborne, the circuit board assembly is installed in the closed metal cavity, electromagnetic shielding is achieved to the greatest extent, external electromagnetic interference is prevented to affect the normal work of the circuit, and stable operation of the fan in complex environment is ensured. The axial flow fan has excellent airflow characteristics and reliable structural strength, can be widely applied in aviation, aerospace, ship and high-end civil equipment, and has considerable market prospect and popularization value. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the embodiments will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0016] Figure 1 It is a structural schematic diagram of the small axial flow fan according to an embodiment of the present application. Figure 2 It is a structural schematic diagram of the rotor according to an embodiment of the present application. Figure 3 It is a structural schematic diagram of the shell according to an embodiment of the present application. Figure 4 It is an assembly schematic diagram of the stator assembly and the shell according to an embodiment of the present application. Figure 5 It is an assembly schematic diagram of the rotor and the shell according to an embodiment of the present application. Figure 6Fig. 1 is a schematic view of a circuit board assembly according to an embodiment of the present application.

[0017] Fig. 1 is a schematic view of a circuit board assembly according to an embodiment of the present application. DETAILED DESCRIPTION

[0018] The embodiments of the present application will be described in detail with reference to the drawings, wherein:

[0019] The above embodiments are only used to illustrate the technical solutions of the present application. It should be understood that, for those skilled in the art, the present application can be modified or equivalent substitutes can be used without departing from the spirit and scope of the present application. Therefore, the present application should not be limited to the above embodiments. The embodiments of the present application are described in detail below with reference to the drawings.

[0020] It should be noted that various aspects of the embodiments described below are within the scope of the claims. It should be apparent that the aspects described herein can be implemented in a very wide variety of forms and that any specific structure and / or function described herein is merely illustrative. Based on the teachings provided herein one skilled in the art will appreciate the various ways in which the aspects described herein can be implemented.

[0021] It should also be noted that the figures provided in the following embodiments are only schematic and that the dimensions of the various components are not necessarily to scale, and that the embodiments can have different configurations without departing from the spirit or essential characteristics of the present application. Furthermore, embodiments can have different configurations and can be implemented in various ways without departing from the spirit or essential characteristics of the present application.

[0022] Furthermore, in the following description, numerous specific details are set forth in order to provide a thorough understanding of the examples. However, it will be apparent to one skilled in the art that the aspects described herein can be practiced without these specific details.

[0023] The embodiment of the present application provides a small axial flow fan, and the small axial flow fan is described below with reference to the accompanying drawings Figures 1 to 6 in detail.

[0024] In one embodiment, with reference to Figure 1 , the small axial flow fan comprises a shell 1, a rotor 2, a stator 8, a shaft, a shaft sleeve 13, a positioning sleeve 3 and a circuit board assembly 12, the shaft is sleeved with a first bearing 4, a second bearing 10 and the positioning sleeve 3, the positioning sleeve 3 is located at a middle region of the shaft, an inner side of the positioning sleeve 3 is provided with a spring 5, the spring 5 is sleeved on the shaft, the first bearing 4 and the second bearing 10 are respectively located at two sides of the positioning sleeve 3, the first bearing 4, the second bearing 10 and the positioning sleeve 3 are installed inside the shaft sleeve 13, an outer side of the shaft sleeve 13 is provided with the stator 8, the rotor 2 is supported and installed on an outer side of the stator 8 through the bearing, a shaft end is axially positioned to the rotor 2 through a nut 11, a rear end of the shell 1 is provided with a metal shielding cavity, the circuit board assembly 12 is fixed in the metal shielding cavity, and a winding tail of the stator 8 is welded at a fixed position of the circuit board assembly 12.

[0025] In the embodiment, the axial flow fan coaxially fixes a series of rotating structural members such as the rotor 2, the bearing, the collar, the spring 5 and the gasket through the shaft sleeve 13, provides sufficient bearing pre-tightening force and reduces the rotational inertia, and ensures that the rotor 2 rotates stably and reduces self-vibration when the fan reaches a rotation speed of 30000 rpm. In order to meet the requirements of electromagnetic capacity on board, the circuit board assembly 12 is installed in a closed metal cavity, and electromagnetic shielding is achieved to the greatest extent.

[0026] Further, the circuit board assembly 12 is designed with a filter capacitor, copper is laid on the whole circuit board, circuit parts prone to radiation emission are arranged with the shortest distance, and the whole is installed and encapsulated in the metal shielding cavity of the shell 1.

[0027] Further, with reference to Figure 3 and Figure 6 , guide vanes are arranged on the frame of the shell 1, and a rotation direction of the guide vanes is opposite to a rotation direction of the rotor 2.

[0028] In specific implementation, seven vane guide vanes are designed on the frame end of the shell 1, and the rotation direction of the guide vanes is opposite to the rotation direction of the rotor 2, which is used for improving wind pressure and reducing aerodynamic noise.

[0029] Further, with reference to Figure 3 , the guide vanes are provided with grooves 14 for lead-out wires. Shielded wires are selected for the axial flow fan, and the grooves 14 for lead-out wires are designed, so that the lead-out wires are convenient to encapsulate and electromagnetically shield after being stretched out of the grooves 14.

[0030] Further, the fan blades of the rotor 2 are prepared and formed in a manner that the maximum outer diameter size is reserved and the fan blade projection surfaces are overlapped. Further, the fan blades of the rotor 2 are prepared and formed in a manner that the maximum outer diameter size is reserved and the fan blade projection surfaces are overlapped.

[0031] In implementation, referring to Figure 2 , the fan blades of the rotor 2 retain the maximum outer diameter size, and the fan projection surface overlap design maximizes the working area of the fan blades, achieving the design effect of large air volume, taking into account the requirements of air volume and air pressure. Among them, the coaxiality of the shaft is the highest, which ensures the coaxiality of the shaft and the shaft sleeve 13, and the positioning point designed by the extension of the shaft ensures the coaxiality of the whole support frame and the shell 1 during installation. The outer hub of the rotor 2 can be used for dynamic balance weight processing of the rotor 2.

[0032] Further, referring to Figure 3 , the bottom wall of the metal shielding cavity is provided with a boss 15, which limits the circuit board assembly 12. The cavity of the shell 1 is left with a boss 15 and a circuit board assembly 12 limiting and fixing, and the circuit board assembly 12 is entirely covered in the sealed metal cavity by pouring sealant, which has the effect of heat conduction and electromagnetic shielding.

[0033] Further, the circuit board assembly 12 is poured in the metal shielding cavity by pouring sealant.

[0034] Further, the second bearing 10 is arranged close to the nut 11, and the hole collar 7 is arranged between the second bearing 10 and the positioning sleeve 3, which supports the bearing.

[0035] Further, the first gasket 6 is arranged between the hole collar 7 and the positioning sleeve 3, and the second gasket 9 is arranged between the hole collar 7 and the second bearing 10.

[0036] Further, in order to meet the use requirements of the fan in harsh vibration environment, the shell 1 and the shaft sleeve 13 are integrally pressure cast, the rotor 2, the shaft and the rotor sleeve are integrally pressure cast, and the stator 8 is fixed by glue coating.

[0037] Further, the shaft sleeve 13 and the stator 8 are limited by the key groove.

[0038] In implementation, referring to Figure 4 , Figure 5 and Figure 6 , the end of the stator 8 winding is reserved through the wire hole of the shell 1, which is welded with the circuit board assembly 12 in the cavity. The stator 8 is installed on the shaft sleeve 13 of the shell 1, and the shaft sleeve 13 and the stator 8 are provided with key grooves for limiting to prevent circumferential rotation. The structure of the first bearing 4, the positioning sleeve 3, the second bearing 10 and other structure is installed in the shaft sleeve 13, and the rotor 2 is installed on the support frame assembly and fixed by the nut 11. The whole structure can be assembled without the circuit board assembly 12, avoiding repeated disassembly and debugging.

[0039] The embodiment provided by the application solves the problem that the small-size direct-current axial flow fan cannot generate large air volume and air pressure in the prior art. The composition structure mainly comprises a shell 1, a rotor 2, a positioning sleeve 3, a bearing, a spring 5, a hole ring 7, a stator 8, a nut 11, a circuit board assembly 12, a shaft sleeve 13 and a gasket. The axial flow fan coaxially fixes a series of rotating structural members such as the rotor 2, the bearing, the ring, the spring 5 and the gasket through the shaft sleeve 13, provides sufficient bearing pre-tightening force and reduces the rotational inertia, ensures that the rotor 2 rotates stably and reduces self-vibration when the fan reaches a rotation speed of 30000 rpm. On the basis of reserving the maximum outer diameter size, the fan blade projection surface overlap design maximizes the working area of the fan blade, and the design effect of large air volume is achieved. The frame end of the shell 1 is designed with guide vanes opposite to the rotation direction of the rotor 2 fan blades to improve the air pressure, and the base number leaf matching design is used to reduce the aerodynamic noise as much as possible. In order to meet the use requirements of the fan in a severe vibration environment, the fan blade and the shaft and the rotor sleeve, the shell 1 and the shaft sleeve 13 are processed by integral die casting, and the stator 8 is fixed by gluing. In order to meet the electromagnetic capacity requirement of the airborne, the circuit board assembly 12 is installed in a closed metal cavity to achieve the maximum electromagnetic shielding. The axial flow fan has excellent airflow characteristics and reliable structural strength, and can be widely applied in aviation, aerospace, ships and high-end civil equipment, and has considerable market prospect and popularization value.

[0040] The small-size axial flow fan with high rotation speed and large air pressure provided by the application improves the assembly sequence, improves the debugging convenience, improves the electromagnetic shielding capacity of the fan product, and ensures that the fan can provide high air volume and large air pressure in a small space on the basis of the traditional axial flow fan.

[0041] The above is only a specific embodiment of the application, but the protection scope of the application is not limited thereto, and any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the application, which should be covered within the protection scope of the application. Therefore, the protection scope of the application should be subject to the protection scope of the claims.

Claims

1. A small axial flow fan characterised in that, The application relates to a motor, which comprises a shell (1), a rotor (2), a stator (8), a shaft, a shaft sleeve (13), a positioning sleeve (3) and a circuit board assembly (12), the shaft is sleeved with a first bearing (4), a second bearing (10) and the positioning sleeve (3), the positioning sleeve (3) is located in the middle region of the shaft, the inner side of the positioning sleeve (3) is provided with a spring (5), the spring (5) is sleeved on the shaft, the first bearing (4) and the second bearing (10) are respectively located on the two sides of the positioning sleeve (3), the first bearing (4), the second bearing (10) and the positioning sleeve (3) are installed in the shaft sleeve (13), the outer side of the shaft sleeve (13) is provided with the stator (8), the rotor (2) is supported and installed on the outer side of the stator (8) through the bearings, the shaft end is axially positioned to the rotor (2) through a nut (11), the rear end of the shell (1) is provided with a metal shielding cavity, the circuit board assembly (12) is fixed in the metal shielding cavity, and the winding starting and ending heads of the stator (8) are welded at the fixed positions of the circuit board assembly (12).

2. The small axial flow fan according to claim 1, characterized by The frame of the shell (1) is provided with guide vanes, the rotation direction of the guide vanes is opposite to the rotation direction of the rotor (2).

3. The small axial flow fan according to claim 2, characterized by The guide vanes are provided with grooves (14) for leading out wires.

4. The compact axial fan of claim 1, wherein The fan blades of the rotor (2) are prepared and formed in the mode of retaining the maximum outer diameter size and combining the overlapping of the fan blade projection surfaces.

5. The compact axial fan of claim 1, wherein The bottom wall of the metal shielding cavity is provided with a boss (15) for limiting the circuit board assembly (12).

6. The small axial flow fan according to claim 5, characterized by The circuit board assembly (12) is filled in the metal shielding cavity through filling glue.

7. The compact axial fan of claim 1, wherein The second bearing (10) is arranged close to the nut (11), and a hole clamping ring (7) is arranged between the second bearing (10) and the positioning sleeve (3).

8. The compact axial fan of claim 1, wherein, A first gasket (6) is arranged between the hole clamping ring (7) and the positioning sleeve (3), and a second gasket (9) is arranged between the hole clamping ring (7) and the second bearing (10).

9. The compact axial fan of claim 1, wherein, The shell (1) and the shaft sleeve (13) are integrally pressure-cast, and the rotor (2), the shaft and the rotor sleeve are integrally pressure-cast.

10. The compact axial fan of claim 1, wherein, The shaft sleeve (13) and the stator (8) are limited through key grooves.

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