Fan motor

Abstract

The present application relates to a kind of fan motor.A kind of fan motor, including shell, rotor assembly and stator assembly, the shell includes rear opening outer shell, inner shell in the outer shell and the cover made of heat conduction material for closing the outer shell opening, the rotation axis of the rotor assembly is rotationally supported on the outer shell, the rotation axis rear end is fixed with the inner shell, the inner shell inner side wall and outer shell front side inner wall between constitute the first chamber for accommodating stator assembly and rotor assembly, the inner shell outer side wall and cover rear side inner wall between constitute the second chamber for accommodating driver, the inner shell is equipped with several blades, when inner shell rotates along with rotation axis, blade rotates and blows to the second chamber side.The present application has good heat dissipation effect, can heat dissipation to adapter and driver integrated in the motor, and can keep the advantages of small volume, low cost.

Description

Technical Field

[0001] This invention relates to a motor for a fan. Background Technology

[0002] Chinese Patent Application No. 201620570015.6 discloses a waterproof and dustproof cooling fan device for an external rotor DC brushless motor, including a fixed base, a rotating shaft core, fan blades, ball bearings, and a rear cover. The fixed base extends inward to form a U-shaped cup with a recess. A central tube extends inward from the middle of the U-shaped cup to form a central tube. A stator assembly is fixedly installed on the outside of the central tube. A step extends out from the inside of the central tube, and ball bearings are fixedly installed at both ends of the step. The rotating shaft core is inserted into the ball bearings, and the fan blades are fixedly installed on the part of the rotating shaft core that extends out of the ball bearings. A rear cover is added to the mouth of the U-shaped cup, and a sealing gasket is added between the rear cover and the mouth of the U-shaped cup. The fan blades are installed inside the rotating shaft core, and a sealing ring is installed between the fan blades and the adjacent ball bearings. The sealing ring is pressed against the ball bearings by a stainless steel clip. These low-cost exhaust fans and electric fans typically use motors connected to AC power and are equipped with adapters to convert 220V AC power into low-voltage DC power. The motors have built-in drivers, which include several high-power electrical components. Generally, only heat dissipation fins are installed on the motor housing, resulting in poor heat dissipation performance. Summary of the Invention

[0003] The purpose of this invention is to provide a fan motor for heat dissipation via an adapter with better heat dissipation performance.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: a fan motor, comprising a housing, a rotor assembly, and a stator assembly. The housing includes a rearward-opening outer housing, an inner housing located within the outer housing, and a cover made of a heat-conducting material for closing the opening of the outer housing. The rotor assembly's rotating shaft is rotatably supported on the outer housing, and the rear end of the rotating shaft is fixed to the inner housing. The inner sidewall of the inner housing and the front inner wall of the outer housing form a first chamber for accommodating the stator assembly and the rotor assembly. The outer sidewall of the inner housing and the rear inner wall of the cover form a second chamber for accommodating the driver. The inner housing is provided with a plurality of blades. When the inner housing rotates with the rotating shaft, the blades rotate and blow air towards the second chamber.

[0005] This invention utilizes blades on the inner casing of the outer rotor to direct airflow towards the second chamber during motor operation. This airflow within the casing improves heat conduction, allowing the air to contact the cover and thus enhancing heat dissipation for the electrical components of the drive unit within the second chamber. Perforations can be made in the outer casing, inner casing, and cover to further improve heat dissipation. The cover can be made of conventional heat-conducting materials used in motor housing manufacturing, such as copper or aluminum alloy. The cover has a shield-shaped structure, which, compared to end plates, increases the contact area with hot air, further improving heat dissipation. Alternatively, existing motor heat dissipation structures, such as cooling fins, can be incorporated into the outer wall of the cover to enhance heat dissipation.

[0006] The present invention improves the inner shell structure, eliminating the need for fan blades at the rear end of the rotor assembly shaft. Instead, blades are installed on the inner shell, which improves heat dissipation while ensuring low production cost and small size of the motor of the present invention.

[0007] Preferably, the adapter is integrated into the second cavity. By integrating the adapter into the second cavity, i.e., by setting the electrical components of the adapter on the circuit board located in the second cavity, it is not necessary to have an adapter with a box outside the motor. Furthermore, the invention has a built-in heat dissipation structure, which can reduce the overall size of the motor while ensuring the normal operation of the adapter's electrical components.

[0008] Preferably, both the adapter and the driver are mounted on a circuit board, which is fixed within the second chamber. The blades are located at the rear end face of the inner housing, and the circuit board is situated on the rear side of the inner housing. The fact that the electrical components of both the adapter and the driver are mounted on a single circuit board further ensures the compact size of the motor of this invention. Furthermore, the circuit board's location on the rear side of the inner housing, within the airflow direction created by the rotation of the inner housing, ensures effective heat dissipation for the electrical components.

[0009] Preferably, the inner wall of the outer casing has two opposing L-shaped mating blocks. The circuit board is inserted between the two mating blocks, which facilitates the subsequent fastening of the circuit board to the outer casing.

[0010] Preferably, the rear end of the outer casing is provided with a boss for supporting the circuit board, and the rear end of the side wall of the outer casing is provided with a through-hole extending rearward, the through-hole being located behind the boss. The boss at the outer casing allows the circuit board to be installed after the motor stator and rotor are installed, facilitating electrical connection between the wires at the motor stator and rotor and the circuit board. Simultaneously, the through-hole facilitates the extension of the power cord, thus aiding in the assembly of the motor of this invention.

[0011] Preferably, the blades are located at the rear end of the inner shell, and the inner shell has several through-holes. The blades at the rear end of the inner shell facilitate airflow towards the rear of the inner shell. The through-holes on the inner shell facilitate airflow between the first chamber and the second chamber.

[0012] Preferably, the front end of the outer casing exposes the front end of the rotating shaft. The interior of the outer casing forms a rearward-extending cylindrical structure. The rotating shaft is rotatably supported on the outer casing by bearings. The front end of the outer casing forms a front bearing chamber, and the rear end of the inner side of the cylindrical structure forms a rear bearing chamber. The rotating shaft is rotatably supported in the front and rear bearing chambers by bearings respectively. The bearings are confined to the front side of the inner housing, with the inner ring of the rearmost bearing contacting and limiting the movement of the inner housing. The inner housing is used not only for positioning and fixing parts of the rotor assembly structure but also for limiting the bearings, making the motor structure of the present invention more compact.

[0013] Preferably, the inner housing has a forward-extending annular portion along its circumferential edge, and the rotor core of the rotor assembly is fixed to the circumferential inner wall of the annular portion. The inner diameter of the front bearing chamber is larger than the inner diameter of the cylindrical structure, and a limiting ring is provided at the front end of the inner wall of the front bearing chamber. The rear end face of the limiting ring contacts and limits the movement of the outer ring of the front bearing. By providing the annular portion, the fixing effect of the rotor core is improved, making the shaft more stable during rotation. The above configuration allows for a smaller inner diameter of the cylindrical structure and a larger front bearing, resulting in a smaller motor size while ensuring operational stability.

[0014] Preferably, the rear end of the outer shell and the front end of the cover have mating stop structures, the outer shell has a male stop structure, the cover has a female stop structure, and the front end of the cover has an open portion extending circumferentially outward from rear to front; the cover has a through second vent hole. After the outer shell and the cover are fitted together, they can be fixed together by bolts or other fasteners. The open portion facilitates the assembly of the outer shell and the cover made of metal material.

[0015] Preferably, the inner housing has several windows, one end of the blade is connected to the inner edge of the window, and the other end of the blade extends rearward. The blade and the aforementioned windows can be obtained by stamping the inner housing using sheet metal stamping. This configuration makes the motor of the present invention more cost-effective.

[0016] This invention has the advantages of good heat dissipation, which can dissipate heat from the adapter and driver integrated inside the motor, while maintaining small size and low cost. Attached Figure Description

[0017] Figure 1This is a cross-sectional view of the fan motor of Example 1.

[0018] Figure 2 This is a schematic diagram of the structure of the fan motor in Example 1 after removing the cover and circuit board.

[0019] Figure 3 A cross-sectional view of the fan motor in this embodiment 2.

[0020] Figure 4 This is a cross-sectional view of the fan motor of Example 3.

[0021] Figure 5 This is a schematic diagram of the structure of the fan motor housing and the circuit board in Embodiment 3.

[0022] Figure 6 This is a schematic diagram of the structure of the fan motor in Example 3 when the inner housing and outer housing are fixed. Detailed Implementation

[0023] The present invention will now be further described with reference to the accompanying drawings and specific embodiments.

[0024] Example 1

[0025] Depend on Figure 1 and Figure 2 As shown, this embodiment discloses a fan motor, including a housing, a rotor assembly, and a stator assembly. The rotor assembly includes a rotating shaft 11 and a rotor core 12. The stator assembly includes a stator core 21. The housing includes an outer shell 3, a cover 4, and an inner shell 5. The outer shell 3 has a rearward opening. The cover 4 is made of aluminum alloy and is used to close the opening of the outer shell 3. The inner shell 5 is rotatably supported and fixed inside the outer shell 3. The rotating shaft 11 is rotatably fixed to the outer shell 3 by two bearings, namely a front bearing 13 and a rear bearing 14. The inner shell 5 is fixed to the rear end of the rotating shaft 11. The rear end of the outer shell 3 and the front end of the cover 4 have mutually cooperating stop structures. The outer shell 3 has a male stop structure 34, and the cover 4 has a female stop structure 43. The front end of the cover has an open portion 44 extending circumferentially outward from rear to front. The outer shell 3 and the cover 4 are fixed together by fasteners.

[0026] The front end of the outer casing 3 forms a front bearing chamber with a forward opening. The middle part of the rotating shaft 11 is rotatably supported in the front bearing chamber by the front bearing 13. The front end of the rotating shaft 11 extends forward to the front side of the outer casing 3 and is used to fix the fan blade. A limiting ring 15 is also provided in the front bearing chamber. The limiting ring 15 is fixed in the front bearing chamber by means of retaining ring fixing, thread fixing, etc., and the rear end face of the limiting ring 15 contacts and limits the contact with the outer ring of the front bearing 13.

[0027] The front end of the outer casing 3 forms a rearwardly extending cylindrical structure 31. The stator core 21 is sleeved and fixed on the outer circumference of the cylindrical structure 31. The rotating shaft 11 is rotatably supported at the rear end of the cylindrical structure 31 via the rear bearing 14. The inner diameter of the front bearing chamber is larger than the inner diameter of the cylindrical structure 31, and the width of the front bearing 13 is larger than the width of the rear bearing 14.

[0028] The rear end of the rotating shaft 11 passes through the cylindrical structure 31 and is fixed to the inner housing 5. The inner housing 5 has a forward-extending annular portion 51 on its circumferential edge. The rotor core 12 is fixed to the inner circumferential wall of the annular portion 51 and sleeved on the outer circumferential side of the stator core 21. The rear bearing 14 is confined to the front side of the inner housing 5. The inner housing 5 has a forward-extending annular extension 54 at its center. The inner ring of the rear bearing 14 contacts and limits the extension 54. The extension 54 of the inner housing 5 is sleeved and fixed on the rotating shaft 11.

[0029] The inner housing 5 has several blades 50 at its rear end. When the inner housing 5 and the rotating shaft 11 rotate, the blades 50 rotate and blow air backward. The inner housing 5 has several through windows 53, each corresponding to a blade 50. One end of each blade 50 is connected to the inner edge of a window 53, and the other end of each blade 50 extends obliquely backward. The blades 50 are machined onto the inner housing 5 using sheet metal stamping. The inner housing 5 also has several through first vent holes 52.

[0030] In this embodiment, the inner wall of the inner housing 5 and the front inner wall of the outer housing 3 form a first chamber 100 for accommodating the stator assembly and the rotor assembly. The outer wall of the inner housing 5 and the rear inner wall of the cover 4 form a second chamber 200 for accommodating the driver. In this embodiment, the adapter is externally mounted. The electrical components of the driver are mounted on the circuit board. The inner wall of the outer housing 3 has several sets of mating structures. Each set of mating structures includes two mating blocks 35 arranged opposite each other with an L-shaped cross-section. The circuit board, on which the driver electrical components are fixed, is inserted between the two mating structures 35. The rear end of the side wall of the outer housing 3 has a through-hole 33 for leading out the power line (not shown in the figure) connected to the circuit board.

[0031] Example 2

[0032] Depend on Figure 3 As shown, the only difference between this embodiment and embodiment 1 is that the rear end of the cover 4 is provided with a second vent 45 that runs through the front and rear.

[0033] Example 3

[0034] Depend on Figures 4 to 6As shown, the difference between this embodiment and embodiment 1 is that: the second chamber 200 of this embodiment integrates an adapter, the electrical components of the adapter and the electrical components of the driver are set on the same circuit board 41, and the circuit board 41 is located behind the inner shell 5; a boss 32 for supporting the circuit board 41 is provided at the rear end of the inner wall of the outer shell 3, and a notch 33 of the outer shell 3 is located behind the boss 32; when the circuit board 41 is fixed on the boss 32 by fasteners, a second ventilation groove 42 is formed between the circuit board 41 and the inner wall of the outer shell 3.

[0035] This invention has the advantages of good heat dissipation, which can dissipate heat from the adapter and driver integrated inside the motor, while maintaining small size and low cost.

Claims

1. A fan motor, comprising a housing, a rotor assembly, and a stator assembly, characterized in that: The housing includes a rearward-opening outer housing, an inner housing located within the outer housing, and a cover made of a heat-conducting material for closing the opening of the outer housing. The rotor assembly's shaft is rotatably supported on the outer housing, and the rear end of the shaft is fixed to the inner housing. The inner sidewall of the inner housing and the front inner wall of the outer housing form a first chamber for accommodating the stator assembly and the rotor assembly. The outer sidewall of the inner housing and the rear inner wall of the cover form a second chamber for accommodating the driver. The inner housing is provided with a plurality of blades. When the inner housing rotates with the shaft, the blades rotate and blow air toward the second chamber. The circuit board is fixed in the second chamber, the blade is disposed at the rear end face of the inner shell, and the circuit board is located on the rear side of the inner shell; The inner wall of the outer shell is provided with two mating blocks that are arranged opposite each other and have an L-shaped cross-section; The blade is provided at the rear end of the inner shell, and the inner shell is provided with a plurality of through first vent holes; The front end of the outer shell exposes the front end of the rotating shaft, and the interior of the outer shell forms a rearwardly extending cylindrical structure; The rear end of the outer shell and the front end of the cover are provided with mutually cooperating stop structures. The outer shell is provided with a male stop structure, the cover is provided with a female stop structure, and the front end of the cover is provided with an open portion extending from back to front and outward in a circumferential direction. The cover is provided with a through second vent hole; The inner shell is provided with several windows, one end of the blade is connected to the inner edge of the window, and the other end of the blade extends to the rear.

2. The fan motor according to claim 1, characterized in that: The second chamber contains an adapter.

3. The fan motor according to claim 2, characterized in that: The adapter and driver are both mounted on a single circuit board.

4. The fan motor according to claim 1, 2, or 3, characterized in that: The rear end of the housing is provided with a boss for supporting the circuit board, and the rear end of the side wall of the housing is provided with a through notch that extends from the inside out and back, and the notch is located behind the boss.

5. The fan motor according to claim 1, 2, or 3, characterized in that: The rotating shaft is rotatably supported on the outer shell by bearings. The front end of the outer shell forms a front bearing chamber, and the rear end of the inner side of the cylindrical structure forms a rear bearing chamber. The rotating shaft is rotatably supported in the front bearing chamber and the rear bearing chamber by bearings respectively. The bearings are restricted to the front side of the inner shell, and the inner ring of the rear bearing contacts and limits the inner shell.

6. The fan motor according to claim 5, characterized in that: The inner housing has a forward-extending annular portion on its circumferential edge, and the rotor core of the rotor assembly is fixed to the circumferential inner wall of the annular portion; the inner diameter of the front bearing chamber is larger than the inner diameter of the cylindrical structure, and a limiting ring is provided at the front end of the inner wall of the front bearing chamber, and the rear end face of the limiting ring contacts and limits the outer ring of the front bearing.

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