An outer rotor electric motor

Abstract

The utility model discloses a kind of outer rotor motors, including motor and motor controller, motor includes shaft, stator assembly, outer rotor and sleeve seat, motor controller includes controller shell, a piece of control circuit board and electric reactor, and inductance capacitor, rectifier and several power switch tubes are provided on control circuit board;The top of cylindrical portion is installed at the bottom of bottom plate;In the inside of cavity, above bottom panel is divided into two areas, one of the areas installs control circuit board, and the other area installs electric reactor, and the axial height H1 of inductance capacitor is less than or equal to the axial height H2 of electric reactor;Power supply lead wire led out from stator assembly passes through wire hole on bottom plate and enters cavity and is electrically connected with control circuit board, power supply lead wire passes through wire protection sleeve, and wire protection sleeve is nested in wire hole. It can effectively reduce the axial height of entire outer rotor motor, and good sealing.

Description

Technical fields:

[0001] This utility model relates to an external rotor motor. Background technology:

[0002] A typical external rotor motor structure consists of two parts: the motor body and the motor controller. For a specific structure, see the utility model patent with patent number CN202121381434.2 and patent name: "A motor controller and its application in an external rotor motor". In this patent, the circuit board adopts a double-layer layout and the capacitors are relatively tall, resulting in a relatively high axial height and large size of the motor controller.

[0003] The market now demands a more compact structure for external rotor brushless motors, requiring a reduction in motor height to save installation space without affecting the motor's outer diameter.

[0004] The overall axial height of current external rotor motors is limited by the height of the electrolytic capacitor and the installation space and creepage distance required for the conductive plates, as detailed below:

[0005] 1. Electrolytic capacitors play a role in filtering, buffering, and protection in controllers. Reducing the height of electrolytic capacitors will affect the smooth operation and lifespan of the motor.

[0006] 2. When the stator assembly is connected to the circuit board in the controller using conductive plates, space needs to be reserved for the three-phase wire terminals to be plugged in and the corresponding creepage distance needs to be provided. For the specific structure, please refer to the utility model patent with patent number CN222915744U and patent name: A rotor and motor.

[0007] 3) The dustproof and waterproof sealing performance needs to be improved. Summary of the Invention:

[0008] The purpose of this utility model is to provide an external rotor motor that solves the technical problem that the total axial height of the existing external rotor brushless motor structure is too high, resulting in a large space required for installation, and the structure is not compact enough, which cannot meet the needs of customers with limited installation space.

[0009] The objective of this utility model is achieved through the following technical solution:

[0010] An external rotor motor includes a motor and a motor controller, wherein:

[0011] The motor includes a rotating shaft, a stator assembly, an outer rotor, and a sleeve base. The sleeve base includes a base plate and a sleeve that protrudes upward from the middle of the base plate. Bearing chambers are provided at both ends of the sleeve, and bearings are installed inside the bearing chambers. The rotating shaft is located inside the sleeve and supported on the bearings. The stator assembly is nested and installed outside the sleeve, and the outer rotor is sleeved outside the stator assembly.

[0012] The motor controller includes a controller housing, a control circuit board, and a reactor. The controller housing includes a bottom panel and a cylindrical part that protrudes axially from the edge of the bottom panel. The bottom panel and the cylindrical part form a cavity to accommodate the control circuit board. An opening is formed at the top of the cylindrical part. The control circuit board is equipped with inductors, capacitors, rectifiers, and several power switching transistors. The top of the cylindrical part is mounted on the bottom of the bottom panel.

[0013] The feature is that the cavity is divided into two areas above the bottom panel. One area is used to install the control circuit board, and the other area is used to install the reactor. The axial height H1 of the inductor and capacitor is less than or equal to the axial height H2 of the reactor.

[0014] In addition, the power leads from the stator assembly pass through the wire holes on the base plate and enter the cavity to connect electrically with the control circuit board. The power leads pass through the wire sleeve, which is nested in the wire hole.

[0015] Preferably, a groove is provided on the bottom panel, the iron core of the reactor is nested in the groove, a rectifier is arranged on the edge of the control circuit board, the rectifier is installed on the top of the L-shaped heat sink, the bottom of the L-shaped heat sink is tightly installed on the bottom panel, the L-shaped heat sink is located between the reactor and the control circuit board, and several power switching tubes are also arranged on the edge of the control circuit board and tightly attached to the inner wall of the cylindrical part for heat dissipation.

[0016] Preferably, an insulating seat is attached to the bottom surface of the base plate by screws, the insulating seat is pressed against the bottom of the cable sleeve, and the power lead passes through the insulating seat into the cavity.

[0017] Preferably, a dust cover is installed below the bearing chamber at the bottom of the sleeve seat, the dust cover seals the bottom of the sleeve seat, and the insulating seat presses against the bottom of the dust cover.

[0018] Preferably, an elastic sealing ring is installed between the dust cover and the inner wall of the bearing chamber.

[0019] Preferably, a second sealing ring is provided between the inner wall of the cylindrical part and the annular boss protruding on the bottom surface of the bottom plate.

[0020] Preferably, the cable sleeve includes a retaining plate portion and a sealing portion that protrudes axially from the middle of the retaining plate portion, a plurality of wire holes passing through the retaining plate portion and the sealing portion, and the middle of the power lead passing through the wire holes.

[0021] Preferably, a first sealing ring is provided inside the wire hole, and the first sealing ring is fitted over the power lead to seal the gap between the power lead and the inner wall of the wire hole.

[0022] Compared with the prior art, this utility model has the following advantages:

[0023] Effect 1: This utility model uses electrolytic capacitors with a relatively low height (i.e., capacitors with a slightly smaller capacitance value). In order not to affect the motor performance, a reactor is added to optimize harmonics and increase the power factor. Moreover, the axial height H1 of the inductor and capacitor is less than or equal to the axial height H2 of the reactor, which can reduce the axial height of the controller housing accordingly.

[0024] Effect 2: Using power leads instead of conductive plates, the power leads from the stator assembly pass through the wire passage holes on the base plate and enter the cavity to electrically connect with the control circuit board. The power leads pass through the protective sleeve, which is nested in the wire passage hole and blocks it. This saves space for the terminals on the control circuit board because the power leads use a wire core with its own insulation, allowing them to bend and coil. No creepage distance is required when the power leads pass through the bearing housing, reducing the height of the stator assembly. Simultaneously, the bearing housing does not need to be arched at the bottom, further reducing its height and thus lowering the overall axial height of the external rotor motor. Attached image description:

[0025] Figure 1 This is a perspective view of one embodiment of the present invention;

[0026] Figure 2 This is another perspective view of Embodiment 1 of this utility model;

[0027] Figure 3 This is a perspective view of the motor portion of Embodiment 1 of this utility model;

[0028] Figure 4 This is an exploded view of the motor portion of Embodiment 1 of this utility model;

[0029] Figure 5 This is a perspective view of the stator assembly according to Embodiment 1 of this utility model;

[0030] Figure 6 This is a perspective view of the motor controller according to Embodiment 1 of this utility model;

[0031] Figure 7 This is an exploded view of the motor controller according to Embodiment 1 of this utility model;

[0032] Figure 8 This is a top view of Embodiment 1 of this utility model;

[0033] Figure 9 yes Figure 8 AA section view;

[0034] Figure 10 yes Figure 9 A magnified view of part C;

[0035] Figure 11 yes Figure 8BB cross-sectional view. Detailed implementation method:

[0036] The present invention will now be described in further detail through specific embodiments and in conjunction with the accompanying drawings.

[0037] Example 1:

[0038] like Figures 1 to 11 As shown, this embodiment provides an external rotor motor, including a motor 8 and a motor controller 100, wherein:

[0039] The motor 8 includes a rotating shaft 81, a stator assembly 82, an outer rotor 83, and a sleeve base 84. The sleeve base 84 includes a base plate 841 and a sleeve 842 protruding upward from the middle of the base plate 841. Bearing chambers 843 are provided at both ends of the sleeve 842, and bearings 844 are installed inside the bearing chambers 843. The rotating shaft 81 is located inside the sleeve 842 and supported on the bearings 844. The stator assembly 82 is nested and installed outside the sleeve 842, and the outer rotor 83 is sleeved outside the stator assembly 82.

[0040] The motor controller 100 includes a controller housing 1, a control circuit board 2, and a reactor 3. The controller housing 1 includes a bottom panel 11 and a cylindrical portion 12 that protrudes axially from the edge of the bottom panel 11. The bottom panel 11 and the cylindrical portion 12 form a cavity 13 to accommodate the control circuit board 2. An opening 121 is formed at the top of the cylindrical portion 12. The control circuit board 2 is provided with inductors and capacitors 21, rectifiers 22, and several power switching transistors 23. The top of the cylindrical portion 12 is mounted on the bottom of the base plate 841.

[0041] The feature is that the cavity 13 is divided into two areas above the bottom panel 11. One area is used to install the control circuit board 2, and the other area is used to install the reactor 3. The axial height H1 of the inductor and capacitor 21 is less than or equal to the axial height H2 of the reactor 3.

[0042] In addition, the power lead 86 from the stator assembly 82 passes through the wire hole 8411 on the base plate 841 and enters the cavity 13 to be electrically connected to the control circuit board 2. The power lead 86 passes through the wire sleeve 9, which is nested in the wire hole 8411.

[0043] The advantages of this invention are as follows: 1. This invention uses a low-profile electrolytic capacitor 21 (i.e., a capacitor with a slightly smaller capacitance value). In order not to affect the motor performance, an inductor is added to optimize harmonics and increase the power factor. Moreover, the axial height H1 of the inductor capacitor 21 is less than or equal to the axial height H2 of the inductor 23, which can correspondingly reduce the axial height of the controller housing. 2. Power leads are used instead of conductive sheets. The power lead 86 led out from the stator assembly passes through the wire hole 8411 on the base plate 841 and enters the cavity 13 to be electrically connected to the control circuit board 2. The power lead 86 passes through the wire sleeve 9, which is nested in the wire hole 8411 and blocks the wire hole 8411. This saves space for the conductive sheet and the terminal on the control circuit board, because the power lead 86 uses a wire core with its own insulation, which can be bent and coiled for easy routing. When the power lead 86 passes through the bearing housing 84, no creepage distance is required, which can reduce the height of the stator assembly. At the same time, the bearing housing 84 does not need to be arched at the bottom, further reducing the height of the bearing housing, thereby reducing the overall axial height of the external rotor motor.

[0044] Preferably, a groove 111 is provided on the bottom panel 11, and the iron core 31 of the reactor 3 is nested in the groove 111 to prevent the reactor 3 from moving. A rectifier 22 is arranged on the edge of the control circuit board 2 and is mounted on the top of the L-shaped heat sink 24. The bottom of the L-shaped heat sink 24 is tightly mounted on the bottom panel 11. The L-shaped heat sink 24 is located between the reactor 3 and the control circuit board 2. Several power switching transistors 23 are also arranged on the edge of the control circuit board 2 and dissipate heat through the inner wall of the cylindrical part 12. This layout is compact and utilizes the heat dissipation of electronic components.

[0045] Preferably, an insulating seat 4 is attached to the bottom surface of the base plate 841 by screws. The insulating seat 4 is pressed against the bottom of the cable sleeve 9. The power lead 86 passes through the insulating seat 4 and enters the cavity 13. This makes installation convenient and can fix the cable sleeve 9.

[0046] Preferably, a dust cover 6 is installed below the bearing chamber 843 at the bottom of the sleeve seat 84. The dust cover 6 seals the bottom of the sleeve seat 84, and the insulating seat 4 is pressed against the bottom of the dust cover 6, which has a good dustproof effect and prevents dust from entering the motor controller.

[0047] Preferably, an elastic sealing ring 7 is installed between the dust cover 6 and the inner wall of the bearing chamber 843 to further improve the sealing performance.

[0048] Preferably, a second sealing ring 85 is provided between the inner wall of the cylindrical part 12 and the annular boss 8412 protruding on the bottom surface of the bottom plate 841 to further improve the sealing performance.

[0049] Preferably, the cable sleeve 9 includes a retaining plate portion 91 and a sealing portion 92 that protrudes axially from the middle of the retaining plate portion 91. A plurality of wire holes 93 pass through the retaining plate portion 91 and the sealing portion 92, and the power lead 86 passes through the wire 93 in the middle. The structure is simple and easy to install.

[0050] Preferably, a first sealing ring 94 is provided inside the wire hole 93. The first sealing ring 94 is fitted over the power lead 86 to seal the gap between the power lead 86 and the inner wall of the wire hole 93, thereby further improving the sealing performance.

[0051] The above embodiments are preferred embodiments of the present utility model, but the embodiments of the present utility model are not limited thereto. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present utility model are equivalent substitutions and are included within the protection scope of the present utility model.

Claims

1. An external rotor motor, comprising a motor (8) and a motor controller (100), wherein: The motor (8) includes a rotating shaft (81), a stator assembly (82), an outer rotor (83), and a sleeve base (84). The sleeve base (84) includes a base plate (841) and a sleeve (842) protruding upward from the middle of the base plate (841). Bearing chambers (843) are provided at both ends of the sleeve (842). Bearings (844) are installed inside the bearing chambers (843). The rotating shaft (81) is located inside the sleeve (842) and supported on the bearings (844). The stator assembly (82) is nested and installed outside the sleeve (842). The outer rotor (83) is sleeved outside the stator assembly (82). The motor controller (100) includes a controller housing (1), a control circuit board (2), and a reactor (3). The controller housing (1) includes a bottom panel (11) and a cylindrical part (12) axially protruding from the edge of the bottom panel (11). The bottom panel (11) and the cylindrical part (12) form a cavity (13) to accommodate the control circuit board (2). An opening (121) is formed at the top of the cylindrical part (12). The control circuit board (2) is provided with an inductor, a capacitor (21), a rectifier (22), and several power switching transistors (23). The top of the cylindrical part (12) is mounted on the bottom of the base plate (841). The feature is that the cavity (13) is divided into two areas above the bottom panel (11), one area is used to install the control circuit board (2), and the other area is used to install the reactor (3). The axial height H1 of the inductor and capacitor (21) is less than or equal to the axial height H2 of the reactor (3). In addition, the power lead (86) from the stator assembly (82) passes through the wire hole (8411) on the base plate (841) and enters the cavity (13) to be electrically connected to the control circuit board (2). The power lead (86) passes through the wire sleeve (9), which is nested in the wire hole (8411).

2. An external rotor motor according to claim 1, characterized in that: A groove (111) is provided on the bottom panel (11). The iron core (31) of the reactor (3) is nested in the groove (111). A rectifier (22) is arranged on the edge of the control circuit board (2). The rectifier (22) is installed on the top of the L-shaped heat sink (24). The bottom of the L-shaped heat sink (24) is tightly installed on the bottom panel (11). The L-shaped heat sink (24) is located between the reactor (3) and the control circuit board (2). Several power switching tubes (23) are also arranged on the edge of the control circuit board (2) and are cooled through the inner wall of the cylindrical part (12).

3. An external rotor motor according to claim 2, characterized in that: An insulating seat (4) is attached to the bottom surface of the base plate (841) by screws. The insulating seat (4) is pressed against the bottom of the wire sheath (9). The power lead (86) passes through the insulating seat (4) and enters the cavity (13).

4. An external rotor motor according to claim 1, 2, or 3, characterized in that: A dust cover (6) is installed below the bearing chamber (843) at the bottom of the sleeve seat (84). The dust cover (6) seals the bottom of the sleeve seat (84), and the insulating seat (4) presses against the bottom of the dust cover (6).

5. An external rotor motor according to claim 4, characterized in that: An elastic sealing ring (7) is installed between the dust cover (6) and the inner wall of the bearing chamber (843).

6. An external rotor motor according to claim 5, characterized in that: A second sealing ring (85) is provided between the inner wall of the cylindrical part (12) and the annular boss (8412) protruding on the bottom surface of the bottom plate (841).

7. An external rotor motor according to claim 6, characterized in that: The cable sleeve (9) includes a retaining plate (91) and a sealing part (92) that protrudes axially from the middle of the retaining plate (91). Several wire holes (93) pass through the retaining plate (91) and the sealing part (92), and the middle of the power lead (86) passes through the wire holes (93).

8. An external rotor motor according to claim 7, characterized in that: A first sealing ring (94) is provided inside the wire hole (93). The first sealing ring (94) is fitted over the power lead (86) to seal the gap between the power lead (86) and the inner wall of the wire hole (93).

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