Brushless coreless motor

Abstract

The invention relates to the technical field of motors, and provides a brushless coreless motor which comprises a shell, a stator assembly arranged in the shell and a rotor assembly supported on the shell. The shell comprises a first cover plate, a second cover plate and a shell body clamped between the cover plates; the rotor assembly is supported on the first cover plate and the second cover plate and is rotationally connected; the brushless coreless motor further comprises a first bearing and a second bearing, the first bearing is a ball bearing, the second bearing is an oil bearing, the side, close to the shell body, of the first cover plate is recessed to form a first groove, the side, close to the shell body, of the second cover plate is recessed to form a second groove, and the peripheral side of the first bearing is fixed to the first groove. The peripheral side of the second bearing is fixed in the second groove; the two ends of the rotor assembly are fixedly inserted into the inner circumferential sides of the first bearing and the second bearing respectively. Compared with the prior art, the axial and radial movement of the motor rotor is kept in a reasonable interval, and the rotation stability of the motor is improved.

Description

Technical Field

[0001] The invention relates to the technical field of motors, and in particular to a brushless coreless motor. Background Art

[0002] Brushless hollow cup motors have been widely used in the fields of motors and generators due to their compact structure, high power density, high working efficiency, and significant energy saving and consumption reduction benefits. In recent years, the industrial field has an increasingly urgent demand for equipment that uses brushless hollow cup motors to directly drive loads. The widespread application of these brushless hollow cup motor direct-drive equipment will produce immeasurable energy-saving benefits.

[0003] In the related art, most of the existing brushless hollow cup motors include a housing, a rotor, and a stator wound around the rotor at intervals, and the housing is composed of a cover plate and a housing body, wherein the part where the rotor of the brushless hollow cup motor is connected to the housing usually uses bearings to provide axial and radial positioning of the rotor. However, the front and rear ends of the rotor of the existing brushless hollow cup motor both use ball bearings to provide axial and radial positioning, wherein the radial movement of the shaft is subject to the radial movement of the inner and outer rings of the ball bearing. If the radial movement of the inner and outer rings of the ball bearing is too small, it will affect the rolling efficiency of the steel ball, thereby causing the instability of the motor rotation. At the same time, the use of the ball bearing structure also puts forward higher requirements on the process of the inner and outer rings and the steel ball.

[0004] Therefore, it is necessary to provide a new brushless hollow cup motor to solve the above technical problems. Summary of the invention

[0005] The object of the present invention is to provide a brushless hollow cup motor with better axial and radial movement control and rotation stability.

[0006] In order to achieve the above object, the present invention provides a brushless hollow cup motor, which includes a housing, a stator assembly fixed in the housing, and a rotor assembly supported by the housing and forming a rotation connection; The housing comprises a first cover plate, a second cover plate and a hollow housing body sandwiched between the first cover plate and the second cover plate; The stator assembly is fixed to the inner circumference of the housing body and is spaced around the outer circumference of the rotor assembly; Two ends of the rotor assembly are respectively supported on the first cover plate and the second cover plate, and are respectively rotatably connected with the first cover plate and the second cover plate; The brushless hollow cup motor also includes a first bearing and a second bearing, the first bearing is a ball bearing, the second bearing is an oil-containing bearing, the first cover plate is recessed on one side close to the shell body to form a first groove, the second cover plate is recessed on one side close to the shell body to form a second groove coaxially arranged with the first groove, the outer peripheral side of the first bearing is fixed in the first groove, and the outer peripheral side of the second bearing is fixed in the second groove; the two ends of the rotor assembly are respectively inserted and fixed to the inner peripheral side of the first bearing and the inner peripheral side of the second bearing.

[0007] Preferably, the first cover plate includes a first cover plate body and a first fixing ring formed by protruding and extending from one side of the first cover plate body close to the outer shell body, and a second fixing ring formed by protruding and extending from one side of the first fixing ring close to the outer shell body, the first fixing ring abuts against the outer shell body, the second fixing ring is inserted into the open end of the outer shell, the first groove is formed on the inner circumference of the second fixing ring, and the outer circumference of the first bearing is welded and fixed in the first groove.

[0008] Preferably, the second cover plate includes a second cover plate body and a third fixing ring formed by protruding and extending from one side of the second cover plate body close to the outer shell body, the second groove is formed on the inner circumference of the third fixing ring, and the outer circumference of the second bearing is riveted and fixed in the second groove.

[0009] Preferably, the stator assembly includes a stator coil coaxially arranged with the shell body and fixed to the inner circumference of the shell body.

[0010] Preferably, the rotor assembly includes a rotating shaft rotatably connected to the first cover plate and the second cover plate respectively, an iron core sleeved and fixed to the rotating shaft, and a permanent magnet sleeved and fixed to the iron core; the permanent magnet is spaced apart from the stator assembly.

[0011] Preferably, the brushless coreless motor further comprises a circuit board, the circuit board is fixed to a side of the second cover plate away from the first cover plate, the stator assembly is electrically connected to the circuit board, and the circuit board is provided with an output terminal.

[0012] Preferably, the brushless coreless motor further comprises a casing with a hollow structure, the casing is sleeved and fixed on the outer peripheral side of the shell, and the casing is made of magnetic conductive material.

[0013] Preferably, a through hole is provided on one side of the housing, and a wire for connecting the outlet terminal extends to the outside of the housing through the through hole.

[0014] Preferably, the brushless hollow cup motor also includes a sensor assembly, which is used to detect the rotation data of the rotor assembly. The sensor assembly includes a sensor magnet fixed on one end of the rotor assembly away from the second bearing and a Hall sensor fixed on a side of the circuit board close to the second cover plate; the Hall sensor and the sensor magnet are arranged relative to each other.

[0015] Compared with the prior art, the brushless hollow cup motor of the present invention comprises a housing, a stator assembly fixed in the housing, and a rotor assembly supported by the housing and rotatably connected; the housing comprises a first cover plate, a second cover plate, and a hollow housing body sandwiched between the first cover plate and the second cover plate; the stator assembly is fixed to the inner circumference of the housing body and is arranged at intervals around the outer circumference of the rotor assembly; the two ends of the rotor assembly are respectively supported by the first cover plate and the second cover plate, and are respectively rotatably connected with the first cover plate and the second cover plate; the brushless hollow cup motor also comprises a first bearing and a second bearing, the first bearing is a ball bearing, the second bearing is an oil-containing bearing, the first cover plate is concave on one side close to the housing body to form a first groove, the second cover plate is concave on one side close to the housing body to form a second groove coaxially arranged with the first groove, the outer circumference of the first bearing is fixed in the first groove, and the outer circumference of the second bearing is fixed in the second groove; the two ends of the rotor assembly are respectively inserted and fixed to the inner circumference of the first bearing and the inner circumference of the second bearing. In the above structure, the axial movement of the motor is controlled by the ball bearing at the front end of the rotor, and the radial movement of the motor is controlled by the oil-containing bearing at the rear end of the rotor. The mixed combination of the two bearings ensures that the axial and radial movement of the motor rotor remains in a reasonable range, reduces the abnormal noise caused by the unstable rotation of the motor, and improves the stability of the motor rotation. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. 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 work, among which: Figure 1 A schematic diagram of the three-dimensional structure of a brushless coreless motor provided in an embodiment of the present invention; Figure 2 A three-dimensional structural exploded view of a brushless coreless motor provided by an embodiment of the present invention; Figure 3 Another perspective exploded view of the brushless coreless motor provided by an embodiment of the present invention; Figure 4for Figure 1 AA line section view; Figure 5 A schematic diagram of the assembly structure of the first bearing and the second bearing provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] Please combine Figures 1 to 5 ,in, Figure 1 A schematic diagram of the three-dimensional structure of a brushless coreless motor provided in an embodiment of the present invention, Figure 2 The three-dimensional structure exploded diagram of the brushless hollow cup motor provided by the embodiment of the present invention is as follows: Figure 3 Another perspective exploded view of the brushless coreless motor provided by the embodiment of the present invention. Figure 4 for Figure 1 AA line cross-sectional view, the embodiment of the present invention provides a brushless hollow cup motor 100, which includes a housing 1, a stator assembly 2 fixed in the housing 1, and a rotor assembly 3 supported by the housing 1 and forming a rotation connection; The housing 1 comprises a first cover plate 11, a second cover plate 12 and a hollow housing body 13 sandwiched between the first cover plate 11 and the second cover plate 12; The stator assembly 2 is fixed to the inner circumference of the housing body 13 and is spaced around the outer circumference of the rotor assembly 3; Two ends of the rotor assembly 3 are respectively supported on the first cover plate 11 and the second cover plate 12, and are rotatably connected with the first cover plate 11 and the second cover plate 12 respectively; For details, please refer to Figure 2 and Figure 3 The brushless hollow cup motor 100 also includes a first bearing 4 and a second bearing 5, the first bearing 4 is a ball bearing, the second bearing 5 is an oil-containing bearing, the first cover plate 11 is recessed on one side close to the shell body 13 to form a first groove 111, the second cover plate 12 is recessed on one side close to the shell body 13 to form a second groove 121 coaxially arranged with the first groove 111, the outer peripheral side of the first bearing 4 is fixed in the first groove 111, and the outer peripheral side of the second bearing 5 is fixed in the second groove 121; the two ends of the rotor assembly 3 are respectively inserted and fixed to the inner peripheral side of the first bearing 4 and the inner peripheral side of the second bearing 5.

[0019] In the above structure, the side where the first bearing 4 is located is the front end of the brushless hollow cup motor 100, and the side where the second bearing 5 is located is the rear end of the brushless hollow cup motor 100. The front end ball bearing controls the axial movement of the motor, and the rear end oil-containing bearing controls the radial movement of the motor. The combination of the two bearings ensures that the axial movement and radial movement of the motor rotor are kept within a reasonable range, thereby improving the stability of the motor rotation and reducing the abnormal noise caused by the unstable rotation of the motor.

[0020] Preferably, please refer to Figure 5 As shown in the assembly structure diagram, in the embodiment of the present invention, the first cover plate 11 includes a first cover plate body 112 and a first fixing ring 113 formed by protruding and extending from one side of the first cover plate body 112 close to the shell body 13, and a second fixing ring 114 formed by protruding and extending from one side of the first fixing ring 113 close to the shell body, the first fixing ring 113 abuts against the shell body 13, the second fixing ring 114 is inserted into the open end of the shell 1, the first groove 111 is formed on the inner peripheral side of the second fixing ring 114, and the outer peripheral side of the first bearing 4 is welded and fixed in the first groove 111; The second cover plate 12 includes a second cover plate body 122 and a third fixing ring 123 formed by extending and protruding from one side of the second cover plate body 122 close to the housing body, the second groove 121 is formed on the inner circumference of the third fixing ring 123, and the outer circumference of the second bearing 5 is riveted and fixed in the second groove 121. For a bearing structure of a ball bearing, welding fixation can ensure the stability of the connection and fixation between the outer ring of the bearing and the first cover plate 11, and does not affect the rotation of the inner ring of the bearing, so as to ensure the axial stability of the ball bearing in the motor; for a bearing structure of an oil-containing bearing, riveting fixation can ensure that the gap between the bearing and the groove of the second cover plate 12 is controlled, so as to ensure the radial stability of the oil-containing bearing in the motor.

[0021] Ginseng Figure 2 and Figure 3 As shown, the stator assembly 2 includes a stator coil 21 coaxially arranged with the housing body 13 and fixed to the inner circumference of the housing body 13. In the embodiment of the present invention, the stator coil 21 and the rotor assembly 3 generate a magnetic field to each other, thereby driving the rotor assembly 3 to rotate.

[0022] The rotor assembly 3 includes a rotating shaft 31 that is rotatably connected to the first cover plate 11 and the second cover plate 12, an iron core 32 that is sleeved and fixed to the rotating shaft 31, and a permanent magnet 33 that is sleeved and fixed to the iron core 32. The permanent magnet 33 is spaced apart from the stator assembly 2. The stator assembly 2 and the stator coil 21 generate a magnetic field to drive the rotating shaft 31 to rotate between the first cover plate 11 and the second cover plate 12, thereby achieving a motor rotation effect.

[0023] The brushless coreless motor 100 further includes a circuit board 6 , which is fixed to a side of the second cover plate 12 away from the first cover plate 11 . The stator assembly 2 is electrically connected to the circuit board 6 , and an output terminal 61 is provided on the circuit board 6 .

[0024] The brushless hollow cup motor 100 also includes a casing 7 with a hollow structure, which is fixed on the outer peripheral side of the shell. The casing 7 is made of magnetic conductive material. The magnetic conductive material design of the casing is conducive to improving the magnetic strength of the stator assembly 2 to improve the motor performance.

[0025] A through hole 71 is provided on one side of the housing 7 , and a wire connected to the outlet terminal 61 extends to the outside of the housing 7 through the through hole 71 .

[0026] In the embodiment of the present invention, the position of the through hole 71 makes the position of the motor outlet clear, which is convenient for assembly and reduces the complexity of motor assembly.

[0027] The brushless hollow cup motor 100 also includes a sensor assembly 8, which is used to detect the rotation data of the rotor assembly 3. The sensor assembly 8 includes a sensor magnet 81 that is sleeved and fixed on one end of the rotor assembly 3 away from the second bearing 5 and a Hall sensor 82 that is fixed on a side of the circuit board 6 close to the second cover plate 12; the Hall sensor 82 is arranged relative to the sensor magnet 81.

[0028] In the embodiment of the present invention, the rotation data of the rotating shaft 31 is collected by the sensor magnet 81, and the Hall sensor 82 senses and collects data with the sensor magnet 81. The Hall sensor 82 processes the rotation data. After the circuit board 6 uniformly collects the sensor data, the processed data is transmitted to an external device for display, so as to facilitate the motor control.

[0029] Compared with the prior art, the brushless hollow cup motor of the present invention comprises a housing, a stator assembly fixed in the housing, and a rotor assembly supported by the housing and rotatably connected; the housing comprises a first cover plate, a second cover plate, and a hollow housing body sandwiched between the first cover plate and the second cover plate; the stator assembly is fixed to the inner circumference of the housing body and is arranged at intervals around the outer circumference of the rotor assembly; the two ends of the rotor assembly are respectively supported by the first cover plate and the second cover plate, and are respectively rotatably connected with the first cover plate and the second cover plate; the brushless hollow cup motor also comprises a first bearing and a second bearing, the first bearing is a ball bearing, the second bearing is an oil-containing bearing, the first cover plate is concave on one side close to the housing body to form a first groove, the second cover plate is concave on one side close to the housing body to form a second groove coaxially arranged with the first groove, the outer circumference of the first bearing is fixed in the first groove, and the outer circumference of the second bearing is fixed in the second groove; the two ends of the rotor assembly are respectively inserted and fixed to the inner circumference of the first bearing and the inner circumference of the second bearing. In the above structure, the axial movement of the motor is controlled by the ball bearing at the front end of the rotor, and the radial movement of the motor is controlled by the oil-containing bearing at the rear end of the rotor. The mixed combination of the two bearings ensures that the axial and radial movement of the motor rotor remains in a reasonable range, reduces the abnormal noise caused by the unstable rotation of the motor, and improves the stability of the motor rotation.

[0030] The above description is only an implementation mode of the present invention. It should be pointed out that, for ordinary technicians in this field, improvements can be made without departing from the creative concept of the present invention, but these all belong to the protection scope of the present invention.

Claims

1. A brushless hollow cup motor, comprising a housing, a stator assembly fixed in the housing, and a rotor assembly supported by the housing and forming a rotational connection; The housing comprises a first cover plate, a second cover plate and a hollow housing body sandwiched between the first cover plate and the second cover plate; The stator assembly is fixed to the inner circumference of the housing body and is spaced around the outer circumference of the rotor assembly; The two ends of the rotor assembly are respectively supported on the first cover plate and the second cover plate, and are respectively rotatably connected with the first cover plate and the second cover plate; characterized in that: The brushless hollow cup motor also includes a first bearing and a second bearing, the first bearing is a ball bearing, the second bearing is an oil-containing bearing, the first cover plate is recessed on one side close to the shell body to form a first groove, the second cover plate is recessed on one side close to the shell body to form a second groove coaxially arranged with the first groove, the outer peripheral side of the first bearing is fixed in the first groove, and the outer peripheral side of the second bearing is fixed in the second groove; the two ends of the rotor assembly are respectively inserted and fixed to the inner peripheral side of the first bearing and the inner peripheral side of the second bearing.

2. The brushless coreless motor according to claim 1, characterized in that: The first cover plate includes a first cover plate body and a first fixing ring formed by protruding and extending from one side of the first cover plate body close to the outer shell body, and a second fixing ring formed by protruding and extending from one side of the first fixing ring close to the outer shell body, the first fixing ring abuts against the outer shell body, the second fixing ring is inserted into the open end of the outer shell, the first groove is formed on the inner circumference of the second fixing ring, and the outer circumference of the first bearing is welded and fixed in the first groove.

3. The brushless coreless motor according to claim 1, characterized in that: The second cover plate includes a second cover plate body and a third fixing ring formed by protruding and extending from one side of the second cover plate body close to the outer shell body, the second groove is formed on the inner circumference of the third fixing ring, and the outer circumference of the second bearing is riveted and fixed in the second groove.

4. The brushless coreless motor according to claim 1, characterized in that: The stator assembly includes a stator coil which is coaxially arranged with the housing body and fixed to the inner circumference side of the housing body.

5. The brushless coreless motor according to claim 1, characterized in that: The rotor assembly comprises a rotating shaft which is rotatably connected with the first cover plate and the second cover plate respectively, an iron core which is sleeved and fixed on the rotating shaft, and a permanent magnet which is sleeved and fixed on the iron core; the permanent magnet is spaced apart from the stator assembly.

6. The brushless coreless motor according to claim 1, characterized in that: The brushless coreless motor further comprises a circuit board, which is fixed to a side of the second cover plate away from the first cover plate, the stator assembly is electrically connected to the circuit board, and an output terminal is provided on the circuit board.

7. The brushless coreless motor according to claim 6, characterized in that: The brushless coreless motor further comprises a casing with a hollow structure, the casing is sleeved and fixed on the outer peripheral side of the shell, and the casing is made of magnetic conductive material.

8. The brushless coreless motor according to claim 7, characterized in that: A through hole is provided on one side of the housing, and a wire connected to the outlet terminal extends to the outside of the housing through the through hole.

9. The brushless coreless motor according to claim 6, characterized in that: The brushless hollow cup motor also includes a sensor assembly, which is used to detect the rotation data of the rotor assembly. The sensor assembly includes a sensor magnet fixed on one end of the rotor assembly away from the second bearing and a Hall sensor fixed on a side of the circuit board close to the second cover plate; the Hall sensor and the sensor magnet are arranged relative to each other.

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