Brushless coreless motor
By using a limiting structure to fix the front cover and outer shell in the brushless hollow cup motor by welding, and by pressing the bracket and outer shell together, the problem of motor wire output position deviation is solved, and the precise and uniform motor wire output position is achieved, thus improving production efficiency.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- AAC MICROTECH (CHANGZHOU) CO LTD
- Filing Date
- 2024-11-12
- Publication Date
- 2026-05-21
AI Technical Summary
In existing brushless coreless motors, the connection between the front cover, bracket, and housing is made by threaded connection, which leads to inconsistent deviations in the cable outlet position, affecting the motor's fixation effect and resulting in a poor user experience.
A limiting structure is used to weld and fix the front cover and the outer shell together, and the bracket and the outer shell are pressed and fixed together, forming a foolproof feature chain to ensure that the motor output position is accurate and uniform, and simplifying the design of the clamping fixture.
It achieves precise and uniform motor output position, reduces the use of jigs and fixtures, saves costs, and improves production efficiency.
Smart Images
Figure CN2024131609_21052026_PF_FP_ABST
Abstract
Description
Brushless Hollow Cup Motor Technical Field
[0001] This invention relates to the field of motor technology, and more particularly to a brushless hollow cup motor. Background Technology
[0002] Brushless coreless motors, due to their compact structure, high power density, high efficiency, and significant energy-saving benefits, have been widely used in electric motors and generators. In recent years, the industrial sector has seen an increasingly urgent demand for equipment that directly drives loads using brushless coreless motors. The widespread application of these brushless coreless motor direct-drive devices will generate immeasurable energy-saving benefits. Technical issues
[0003] In related technologies, most existing brushless coreless motors include a front cover, a rotor, a stator wound at intervals around the rotor, and a support. The front cover and the support are respectively located at opposite ends of the stator, and the motor rotates through the mutual drive of the stator and rotor. The stator includes a housing fixed to the front cover and windings fixed inside the housing. The rotor generally includes a shaft and magnets fixed to the outer periphery of the shaft, and the motor rotates through the mutual drive of the magnets and windings. However, the existing front cover, support, and housing are connected by threaded connections. Threaded connections cannot accurately position the relative positions of the three components, and this limitation leads to inconsistent deviations in the wire exit positions. Furthermore, simply adding additional clamps to assist in precise adjustment of the motor wire exit positions affects the positions of the four fixing holes on the front cover, ultimately causing the motor to fail to be fixed, resulting in a poor user experience.
[0004] Therefore, it is necessary to provide a new brushless coreless motor to solve the above-mentioned technical problems. Technical solutions
[0005] The purpose of this invention is to provide a brushless hollow cup motor with a simple structure, which facilitates ensuring accurate and uniform motor output position, saves costs, and improves production efficiency.
[0006] To achieve the above objectives, the present invention provides a brushless coreless motor, comprising a housing, a stator assembly fixed to the housing, and a rotor assembly supported on and rotatably connected to the housing. The stator assembly is arranged around the rotor assembly and spaced apart from it. The brushless coreless motor further includes a front cover and a bracket respectively mounted on both ends of the housing, a circuit board fixed to the side of the bracket away from the housing, and a lead-out terminal fixed to the side of the circuit board away from the housing. The front cover is fixed to one end of the housing by a first limiting structure through a snap-fit and welding, and the bracket is fixed to the other end of the housing by a second limiting structure through a snap-fit and pressing. The rotor assembly is rotatably connected to the front cover and the bracket.
[0007] Preferably, the outer casing includes a hollow cylindrical outer casing body, an annular connecting portion extending radially inward from one end of the outer casing body, and a positioning hole penetrating the connecting portion; the front cover includes a front cover body, an annular first boss protruding from the side of the front cover body near the outer casing, a second boss protruding from the side of the first boss near the outer casing, a positioning post protruding from the side of the first boss near the outer casing, and a through hole penetrating the second boss along its axial direction; the connecting portion abuts against the first boss on the side near the front cover, the inner side of the connecting portion is sleeved on the outer periphery of the second boss, and the positioning post is inserted and fixed in the positioning hole; the positioning hole and the positioning post together constitute the first limiting structure; the stator assembly is fixed to the inner wall of the outer casing body, and one end of the rotor assembly is inserted into the through hole and forms a rotatable connection.
[0008] Preferably, the outer casing further includes a plurality of limiting grooves formed by a recess in the other end of the outer casing body along its axial direction, and limiting walls formed in each of the limiting grooves and extending protruding towards the support; the support includes a support body, an annular contact portion extending protruding from the side of the support body away from the outer casing, a limiting protrusion formed protruding from the outer periphery of the support body, and a clearance groove formed by a recess in the outer periphery of the support body. The limiting protrusion and the clearance groove are distributed circumferentially along the support body, and the limiting protrusion is located at the opening of the clearance groove. The support body is inserted into one end of the outer casing body and fixed to the inner sidewall of the outer casing body. The contact portion abuts against the outer casing body on the side near the outer casing body. The limiting protrusion is disposed in the limiting groove, and the limiting wall is disposed in the clearance groove. The limiting protrusion, the limiting groove, the limiting wall, and the clearance groove together constitute the second limiting structure; the other end of the rotor assembly is supported on the support body and forms a rotatable connection.
[0009] Preferably, the bracket further includes at least two third protrusions extending from the side of the bracket body away from the outer shell; the circuit board includes a circuit board body and at least two slot structures formed by the recesses of the circuit board body at intervals, and each of the third protrusions is respectively disposed in one of the slot structures.
[0010] Preferably, the stator assembly includes a coil winding that is coaxially arranged with and fixed to the housing.
[0011] Preferably, the rotor assembly includes a rotating shaft that is rotatably connected to the front cover and the bracket, an iron core sleeved and fixed to the rotating shaft, and a permanent magnet sleeved and fixed to the iron core; the permanent magnet and the stator assembly are spaced apart from each other.
[0012] Preferably, the brushless hollow cup motor further includes a first bearing, which is sleeved and fixed to one end of the rotating shaft near the front cover, and the outer periphery of the first bearing is fixed inside the front cover.
[0013] Preferably, the brushless hollow cup motor further includes a second bearing, which is sleeved on the end of the rotating shaft away from the front cover, and the outer periphery of the second bearing is fixed inside the bracket.
[0014] Preferably, the brushless hollow cup motor further includes a sensor assembly for detecting the rotation data of the rotating shaft. The sensor assembly includes a sensor magnet sleeved and fixed to one end of the rotating shaft away from the second bearing and a Hall sensor fixed to the side of the circuit board near the bracket; the Hall sensor and the sensor magnet are spaced apart from each other.
[0015] Preferably, the brushless hollow cup motor further includes a protective cover, which is respectively fitted and fixed to the front cover and the outer shell; a clearance position is provided on one side of the protective cover, and the outgoing terminal on the circuit board is located within the clearance position. Beneficial effects
[0016] Compared with the prior art, in the brushless coreless motor of the present invention, the stator assembly is fixed inside the housing, and the stator assembly is arranged around and spaced from the rotor assembly, forming a rotatable connection between the rotor assembly and the housing. The brushless coreless motor also includes a front cover and a bracket respectively installed at both ends of the housing, a circuit board fixed to the side of the bracket away from the housing, and a terminal block fixed to the side of the circuit board away from the housing. The front cover and the housing are fixed to one end of the housing by a first limiting structure through a snap-fit and welding, and the bracket and the housing are fixed to the other end of the housing by a second limiting structure through a snap-fit and pressing. The rotor assembly is rotatably connected to the front cover and the bracket respectively. By fixing the housing by snap-fit and welding the front cover and the housing by the first limiting structure, and fixing the housing by snap-fit and pressing the bracket and the housing by the second limiting structure, the front cover, housing, bracket, and circuit board are designed with anti-mistake features at specific positions to form an anti-mistake feature chain, which together achieves the uniformity of the motor's terminal block position. At the same time, by integrating these features into the components themselves, the design of the fixture is simplified, the use of fixtures is reduced, and costs are indirectly saved and production efficiency is improved. Attached Figure Description
[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort, wherein:
[0018] Figure 1 is a three-dimensional structural schematic diagram of the brushless hollow cup motor provided in an embodiment of the present invention;
[0019] Figure 2 is an exploded three-dimensional view of the brushless hollow cup motor provided in an embodiment of the present invention;
[0020] Figure 3 is a cross-sectional view along line AA in Figure 1;
[0021] Figure 4 is a schematic diagram of the outer shell provided in an embodiment of the present invention;
[0022] Figure 5 is a schematic diagram of the structure of the bracket provided in an embodiment of the present invention.
[0023] Among them, 100 is a brushless hollow cup motor; 1 is a shell; 11 is the shell body; 12 is a connecting part; 13 is a limiting groove; 14 is a limiting wall; 15 is a positioning hole; 2 is a stator assembly; 3 is a rotor assembly; 31 is a permanent magnet; 32 is an iron core; 33 is a rotating shaft; 4 is a front cover; 41 is the front cover body; 42 is the first boss; 43 is the second boss; 44 is a positioning post; 45 is a through hole; 5 is a bracket; 51 is the bracket body; 52 is a contact part; 53 is a limiting protrusion; 54 is a clearance groove; 55 is the third boss; 6 is a circuit board; 61 is the circuit board body; 62 is a slot structure; 7 is a wire outlet terminal; 8 is the first bearing; 9 is the second bearing; 10 is a sensor assembly; 101 is a sensor magnet; 102 is a Hall sensor; 20 is a protective cover; 201 is a clearance position. Embodiments of the present invention
[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0025] Referring to Figures 1 to 5, this embodiment of the invention provides a brushless coreless motor 100, which includes a housing 1, a stator assembly 2 fixed to the housing 1, and a rotor assembly 3 supported on and rotatably connected to the housing 1. The stator assembly 2 is arranged around the rotor assembly 3 and spaced apart from the rotor assembly 3. The brushless coreless motor 100 also includes a front cover 4 and a bracket 5 respectively installed at both ends of the housing 1, a circuit board 6 fixed to the side of the bracket 5 away from the housing 1, and a terminal 7 fixed to the side of the circuit board 6 away from the housing 1. The front cover 4 and the housing 1 are fixed to one end of the housing 1 by a first limiting structure through a snap-fit and welding, and the bracket 5 and the housing 1 are fixed to the other end of the housing 1 by a second limiting structure through a snap-fit and pressing. The rotor assembly 3 is rotatably connected to the front cover 4 and the bracket 5.
[0026] The outer casing 1 is used to fix the stator assembly 2 and support the rotation of the rotor assembly 3. The rotor assembly 3 is driven to rotate by the mutual magnetic field generated by the stator assembly 2 and the rotor assembly 3, so as to realize the rotation of the whole motor.
[0027] Specifically, by fixing the stator assembly 2 inside the housing 1, the stator assembly 2 is arranged around the rotor assembly 3 and spaced apart from the rotor assembly 3, forming a rotatable connection between the rotor assembly 3 and the housing 1; the brushless hollow cup motor 100 also includes a front cover 4 and a bracket 5 respectively installed at both ends of the housing 1, a circuit board 6 fixed to the side of the bracket 5 away from the housing 1, and a terminal 7 fixed to the side of the circuit board 6 away from the housing 1; the front cover 4 and the housing 1 are fixed to one end of the housing 1 by a first limiting structure through a snap-fit and welding, and the bracket 5 and the housing 1 are fixed to the housing 1 by a second limiting structure through a snap-fit and pressing. At the other end of the shell 1, the rotor assembly 3 is rotatably connected to the front cover 4 and the bracket 5 respectively. The front cover 4 and the shell 1 are fixed by welding together through the first limiting structure, and the bracket 5 and the shell 1 are fixed to the shell 1 by forming a locking and pressing connection through the second limiting structure. This makes the front cover 4, the shell 1, the bracket 5 and the circuit board 6 designed with anti-foolproof features at specific positions to form an anti-foolproof feature chain, which together realizes the uniformity of the outlet position of the motor's outlet terminal 7. At the same time, it integrates the characteristics of the components themselves, simplifies the design of the fixture, reduces the use of fixtures, and indirectly saves costs and improves production efficiency.
[0028] In this embodiment, the outer shell 1 includes a hollow columnar outer shell body 11, an annular connecting portion 12 extending radially inward from one end of the outer shell body 11, and a positioning hole 15 formed through the connecting portion 12.
[0029] In this embodiment, the front cover 4 includes a front cover body 41, a first protrusion 42 extending annularly from the side of the front cover body 41 near the outer shell 1, a second protrusion 43 extending from the side of the first protrusion 42 near the outer shell 1, a positioning post 44 protruding from the side of the first protrusion 42 near the outer shell 1, and a through hole 45 formed by penetrating the second protrusion 43 along the axial direction of the second protrusion 43; the connecting part 12 abuts against the first protrusion 42 on the side near the front cover 4, the inner side of the connecting part 12 is sleeved on the outer periphery of the second protrusion 43, and the positioning post 44 is inserted and fixed in the positioning hole 15. The positioning hole 15 and the positioning post 44 together constitute the first limiting structure; the stator assembly 2 is fixed to the inner side wall of the outer shell body 11, and the rotor assembly 3 is disposed in the through hole 45 and forms a rotatable connection; the first boss 42 of the front cover 4 abuts against the end face of the outer shell 1, the second boss 43 is disposed in the outer shell 1, and the positioning post 44 is inserted into the positioning hole 15, so that the positioning post 44 and the positioning hole 15 form a foolproof fit, thereby facilitating the assembly between the front cover 4 and the outer shell 1.
[0030] In this embodiment, the outer casing 1 further includes a plurality of limiting grooves 13 formed by a recess on the periphery of the other end of the outer casing body 11, and a limiting wall 14 extending from the side of each limiting groove 13 near the bracket 5. The front cover 4 is fixed to the connecting part 12, the stator assembly 2 is fixed to the inner sidewall of the outer casing body 11, and the bracket 5 is disposed in the other end of the outer casing body 11 and is snapped and fixed with the limiting wall 14. The outer casing body 11 is used to fix the stator assembly 2, and the connecting part 12 is welded and fixed to the front cover 4, so that the front cover 4 and the outer casing 1 are well fixed as a whole. The limiting grooves 13 and the limiting wall 14 form a foolproof connection with the bracket 5, ensuring that the motor output position is accurate and uniform.
[0031] In this embodiment, the bracket 5 includes a bracket body 51, an annular contact portion 52 extending from the side of the bracket body 51 away from the outer shell 1, a limiting protrusion 53 protruding from the outer periphery of the bracket body 51, and a relief groove 54 recessed from the outer periphery of the bracket body 51. The limiting protrusion 53 and the relief groove 54 are distributed circumferentially along the bracket body 51, and the limiting protrusion 53 is located at the opening of the relief groove 54. The bracket body 51 is inserted into one end of the outer shell body 11 and fixed to the inner sidewall of the outer shell body 11. The contact portion 52 abuts against the outer shell body 11 on the side near the outer shell body 11. The limiting protrusion 53 is disposed in the limiting groove 13, and the limiting wall 14 is disposed in the relief groove 54. The limiting protrusion 53, the limiting groove 13, the limiting wall 14, and the clearance groove 54 together constitute the second limiting structure; the other end of the rotor assembly 3 is supported on the bracket body 51 and forms a rotatable connection. By setting the limiting wall 14 in the clearance groove 54, the limiting protrusion 53 is locked in the limiting groove 13, realizing the foolproof cooperation between the limiting groove 13 and the limiting protrusion 53. The limiting groove 13 and the limiting protrusion 53 are designed with foolproof features at specific positions to form a foolproof feature chain, which together realizes the uniformity of the motor output position.
[0032] Optionally, the limiting protrusion 53 can be a limiting block or a limiting post, etc.
[0033] In this embodiment, the bracket 5 further includes at least two third protrusions 55 extending from the side of the bracket body 51 away from the outer shell 1; the circuit board 6 includes a circuit board body 61 and at least two slot structures 62 formed by recesses in the circuit board body 61 at intervals, with each third protrusion 55 disposed within one of the slot structures 62. The third protrusions 55 and the slot structures 62 form a foolproof chain, resulting in good mutual positioning between the bracket 5 and the circuit board 6, facilitating the alignment of the wire exit position of the terminal 7 with the direction of the front cover 4 and the limiting protrusion 53, thus achieving uniformity in the motor wire exit position.
[0034] In this embodiment, the stator assembly 2 is a coil winding coaxially arranged with and fixed to the housing 1. The coil winding and the rotor assembly 3 generate a magnetic field to drive the rotor assembly 3 to rotate.
[0035] In this embodiment, the rotor assembly 3 includes a rotating shaft 33 rotatably connected to the front cover 4 and the bracket 5, an iron core 32 fixed to the rotating shaft 33, and a permanent magnet 31 fixed to the iron core 32; the permanent magnet 31 is spaced apart from the stator assembly 2. The stator assembly 2 and the permanent magnet 31 generate a magnetic field with each other, driving the rotating shaft 33 to rotate between the front cover 4 and the bracket 5, thereby achieving the motor rotation effect.
[0036] In this embodiment, the brushless hollow cup motor 100 further includes a first bearing 8, which is sleeved and fixed to one end of the rotating shaft 33 near the front cover 4, and the outer periphery of the first bearing 8 is fixed inside the front cover 4. The first bearing 8 reduces the friction between the rotating shaft 33 and the front cover 4, thereby improving the rotation efficiency of the rotating shaft 33.
[0037] In this embodiment, the brushless hollow cup motor 100 further includes a second bearing 9, which is sleeved on the end of the rotating shaft 33 away from the front cover 4, and the outer periphery of the second bearing 9 is fixed inside the bracket 5. The second bearing 9 supports the rotating shaft 33 within the bracket 5, ensuring good rotational stability at both ends of the rotating shaft 33.
[0038] In this embodiment, the brushless hollow cup motor 100 further includes a sensor assembly 10. The sensor assembly 10 is used to detect the rotation data of the rotating shaft 33. The sensor assembly 10 includes a sensor magnet 101 sleeved and fixed to the end of the rotating shaft 33 away from the second bearing 9, and a Hall sensor 102 fixed to the side of the circuit board 6 near the bracket 5. The Hall sensor 102 and the sensor magnet 101 are spaced apart. The rotation data of the rotating shaft 33 is collected by the sensor magnet 101, and the sensor magnet 101 and the Hall sensor 102 transmit signals to each other. The rotation data is processed by the Hall sensor 102, and the processed data is transmitted to an external device for display.
[0039] In this embodiment, the brushless hollow cup motor 100 further includes a protective cover 20, which is respectively sleeved and fixed to the front cover 4 and the outer shell 1; a clearance position 201 is provided on one side of the protective cover 20, and the outgoing terminal 7 on the circuit board 6 is located in the clearance position 201. This facilitates the outgoing terminal 7 to exit the circuit.
[0040] Compared with the prior art, in the brushless coreless motor of the present invention, the stator assembly is fixed inside the housing, and the stator assembly is arranged around and spaced from the rotor assembly, forming a rotatable connection between the rotor assembly and the housing. The brushless coreless motor also includes a front cover and a bracket respectively installed at both ends of the housing, a circuit board fixed to the side of the bracket away from the housing, and a terminal block fixed to the side of the circuit board away from the housing. The front cover and the housing are fixed to one end of the housing by a first limiting structure through a snap-fit and welding, and the bracket and the housing are fixed to the other end of the housing by a second limiting structure through a snap-fit and pressing. The rotor assembly is rotatably connected to the front cover and the bracket respectively. By fixing the housing by snap-fit and welding the front cover and the housing by the first limiting structure, and fixing the housing by snap-fit and pressing the bracket and the housing by the second limiting structure, the front cover, housing, bracket, and circuit board are designed with anti-mistake features at specific positions to form an anti-mistake feature chain, which together achieves the uniformity of the motor's terminal block position. At the same time, by integrating these features into the components themselves, the design of the fixture is simplified, the use of fixtures is reduced, and costs are indirectly saved and production efficiency is improved.
[0041] The above description is merely an embodiment of the present invention. It should be noted that those skilled in the art can make improvements without departing from the inventive concept of the present invention, but these improvements all fall within the protection scope of the present invention.
Claims
1. A brushless cupless motor comprising a housing, a stator assembly fixed to said housing, and a rotor assembly supported by said housing and in rotational connection with said housing, said stator assembly being disposed about and spaced from said rotor assembly; characterized in that, The brushless hollow cup motor further includes a front cover and a bracket respectively installed at both ends of the housing, a circuit board fixed to the side of the bracket away from the housing, and a wire outlet terminal fixed to the side of the circuit board away from the housing; the front cover and the housing are fixed to one end of the housing by a first limiting structure through a snap-fit and welding, and the bracket and the housing are fixed to the other end of the housing by a second limiting structure through a snap-fit and pressing; the rotor assembly is rotatably connected to the front cover and the bracket respectively.
2. The brushless, hollow cup motor of claim 1, wherein, The outer casing includes a hollow cylindrical outer casing body, an annular connecting portion extending radially inward from one end of the outer casing body, and a positioning hole penetrating the connecting portion; the front cover includes a front cover body, an annular first boss protruding from the side of the front cover body near the outer casing, a second boss protruding from the side of the first boss near the outer casing, a positioning post protruding from the side of the first boss near the outer casing, and a through hole penetrating the second boss along its axial direction; the connecting portion abuts against the first boss on the side near the front cover, the inner side of the connecting portion is sleeved on the outer periphery of the second boss, and the positioning post is inserted and fixed in the positioning hole; the positioning hole and the positioning post together constitute the first limiting structure; the stator assembly is fixed to the inner wall of the outer casing body, and one end of the rotor assembly is inserted into the through hole and forms a rotatable connection.
3. The brushless, hollow cup motor of claim 2, wherein, The outer casing further includes a plurality of limiting grooves formed by a recess in the other end of the outer casing body along its axial direction, and limiting walls formed in each limiting groove and extending protruding towards the support; the support includes a support body, an annular contact portion extending protruding from the side of the support body away from the outer casing, a limiting protrusion formed protruding from the outer periphery of the support body, and a clearance groove formed by a recess in the outer periphery of the support body. The limiting protrusion and the clearance groove are distributed circumferentially along the support body, and the limiting protrusion is located at the opening of the clearance groove. The support body is inserted into one end of the outer casing body and fixed to the inner sidewall of the outer casing body. The contact portion abuts against the outer casing body on the side near the outer casing body. The limiting protrusion is disposed in the limiting groove, and the limiting wall is disposed in the clearance groove. The limiting protrusion, the limiting groove, the limiting wall, and the clearance groove together constitute the second limiting structure; the other end of the rotor assembly is supported on the support body and forms a rotatable connection.
4. The brushless, hollow cup motor of claim 3, wherein, The bracket further includes at least two third protrusions extending from the side of the bracket body away from the outer shell; the circuit board includes a circuit board body and at least two slot structures formed by the recesses of the circuit board body at intervals, and each of the third protrusions is respectively disposed in one of the slot structures.
5. The brushless, hollow cup motor of claim 1, wherein, The stator assembly includes coil windings that are coaxially arranged with and fixed to the housing.
6. The brushless, hollow cup motor of claim 1, wherein, The rotor assembly includes a rotating shaft that is rotatably connected to the front cover and the bracket, an iron core that is sleeved and fixed to the rotating shaft, and a permanent magnet that is sleeved and fixed to the iron core; the permanent magnet and the stator assembly are spaced apart from each other.
7. The brushless, hollow cup motor of claim 6, wherein, The brushless hollow cup motor also includes a first bearing, which is sleeved and fixed to one end of the rotating shaft near the front cover, and the outer periphery of the first bearing is fixed inside the front cover.
8. The brushless, hollow cup motor of claim 6, wherein, The brushless hollow cup motor also includes a second bearing, which is sleeved on the end of the rotating shaft away from the front cover, and the outer periphery of the second bearing is fixed inside the bracket.
9. The brushless, hollow cup motor of claim 6, wherein, The brushless hollow cup motor also includes a sensor assembly for detecting the rotation data of the rotating shaft. The sensor assembly includes a sensor magnet sleeved and fixed to one end of the rotating shaft away from the second bearing and a Hall sensor fixed to the side of the circuit board near the bracket; the Hall sensor and the sensor magnet are spaced apart from each other.
10. The brushless, hollow cup motor of claim 1, wherein, The brushless hollow cup motor also includes a protective cover, which is respectively fitted and fixed to the front cover and the outer shell; a clearance position is provided on one side of the protective cover, and the outgoing terminal on the circuit board is located in the clearance position.