Brushless motor with compact structure

Abstract

The utility model discloses a brushless motor with a compact structure. A rotor assembly comprises a round cover-shaped rotating disc, a casing, a magnetic ring and a copper sleeve. A limiting outer ring and a limiting inner ring are arranged at the bottom of the turntable; the shell is sleeved on the limiting outer ring; the magnetic ring is arranged on the inner circumference of the shell; a limiting groove matched with the limiting inner ring is formed in the periphery of the copper sleeve; the stator assembly comprises a bottom plate, a stator core, a circuit board and an axis; the axle center is arranged in the copper sleeve in a penetrating manner and extends upwards out of the copper sleeve; an iron core mounting part is arranged on the periphery of the copper sleeve, and the stator iron core sleeves the iron core mounting part; the circuit board is bonded below the bottom plate; according to the utility model, the structure of the brushless motor is optimized, the loosening and vibration among parts can be reduced, and the stability of the whole structure is improved; the improved copper bush structure is favorable for improving the bearing assembly stability and high supporting rigidity, so that the rotor is higher in rotation stability, better in concentricity and higher in precision, and is favorable for miniaturizing the structure.

Description

Technical Field

[0001] The utility model relates to the technical field of brushless motors, in particular to a brushless motor with a compact structure. Background Art

[0002] Brushless motors are usually composed of fixed windings and rotating magnetic poles. Brushless motors are widely used in industries, automobiles, aerospace and other fields. In recent years, imaging devices such as projectors or cameras have become increasingly miniaturized and thinner, so the brushless motors used in them also need to become smaller accordingly. However, miniaturized brushless motors face some challenges in terms of concentricity, stability and assembly performance. Specifically, as the size decreases, the concentricity requirements between the various components of the brushless motor become more stringent. Minor errors or asymmetries may cause poor alignment between the rotor and the fixed components, affecting the operating efficiency and performance of the motor; in addition, smaller brushless motors are more susceptible to external environmental factors such as vibration, temperature changes, etc., which affect their stability and performance; at the same time, smaller brushless motors may increase the complexity and difficulty of assembly operations.

[0003] In practical applications, brushless motors in the prior art may sacrifice some performance indicators, such as durability and stability, to meet size and weight requirements due to limited design space for miniaturized brushless motors, resulting in low overall concentricity; at the same time, excessive use of screws and other fasteners can easily cause looseness during operation, resulting in high noise, low stability, and poor output accuracy.

[0004] Therefore, further research and development is needed to solve the problems of concentricity, stability and assembly performance in the above-mentioned prior art and improve its performance and reliability. Utility Model Content

[0005] Therefore, in order to solve the problems existing in the above-mentioned prior art, the purpose of the utility model is to provide a brushless motor with a compact structure, optimize the structure of the brushless motor, make the layout between the rotor assembly, the stator assembly, and the bearing structure more reasonable and compact, help reduce looseness and vibration between parts, and improve the stability of the overall structure.

[0006] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0007] A brushless motor with a compact structure, comprising:

[0008] The rotor assembly comprises a dome-shaped turntable, a housing, a magnetic ring and a copper sleeve; the housing is arranged below the turntable; a limit outer ring and a limit inner ring protruding toward the copper sleeve are arranged at the bottom of the turntable; the housing is sleeved on the limit outer ring; the magnetic ring is arranged on the inner periphery of the housing and is spaced from the end of the limit outer ring; a limit groove matching the limit inner ring is arranged on the outer periphery of the copper sleeve;

[0009] The stator assembly includes a bottom plate, a stator core, a circuit board, and an axis; the axis is inserted into the inner cavity of the copper sleeve and extends upward to the outside of the copper sleeve; the top of the turntable is sleeved on the outer periphery of one end of the axis extending outside the copper sleeve; a core mounting portion is concavely provided radially inwardly on the outer periphery of the copper sleeve, and the stator core is sleeved on the core mounting portion; the circuit board is bonded and arranged under the bottom plate;

[0010] A bearing structure is provided, wherein the bearing structure is located inside the copper sleeve and sleeved on the outer periphery of the shaft center; an upper sealing member and a lower sealing member are provided on the upper part and the lower part of the bearing structure respectively.

[0011] Furthermore, a cavity matching the outer diameter of the copper sleeve is provided on the inner side of the turntable, and the edge of the cavity extends downward to form the limiting inner ring; the upper part of the copper sleeve extends into the cavity, and the limiting groove is opposite to the gap of the limiting inner ring.

[0012] Furthermore, the side walls of the limiting outer ring and the limiting inner ring close to each other are respectively provided with outer inclined surfaces and inner inclined surfaces inclined in opposite directions.

[0013] Furthermore, a copper sleeve installation groove for installing the copper sleeve is provided at the center of the base plate; a mounting post adapted to the copper sleeve installation groove is provided on the copper sleeve; and the copper sleeve is embedded in the copper sleeve installation groove through the mounting post.

[0014] Furthermore, the bearing structure includes an upper bearing and a lower bearing; the inner wall of the copper sleeve is respectively provided with an upper bearing mounting portion and a lower bearing mounting portion adapted to the upper bearing and the lower bearing; the ends of the upper bearing and the lower bearing close to each other are respectively abutted against the upper bearing mounting portion and the lower bearing mounting portion.

[0015] Furthermore, the upper sealing member is a steel wire retaining ring arranged at the top of the upper bearing; and the lower sealing member is a corrugated washer arranged at the bottom of the lower bearing.

[0016] Furthermore, a relative magnetic gasket and an axial gasket are provided between the top of the copper sleeve and the inner top of the turntable; a first groove for installing the magnetic gasket is provided at the top of the copper sleeve, and a second groove for installing the axial gasket is provided at the inner top of the turntable.

[0017] Furthermore, the bearing structure is an oil-containing bearing, and a flexible oil-absorbing member is provided between the outer periphery of the oil-containing bearing and the inner wall of the copper sleeve.

[0018] Furthermore, the upper seal can also be an oil-stop gasket arranged on the top of the oil-containing bearing; the lower seal is a stop ring arranged at the bottom of the bearing structure; an axial blind hole is provided at the inner bottom of the copper sleeve, and a brake gasket is provided in the axial blind hole.

[0019] Furthermore, a plurality of limiting protrusions are provided at intervals along the circumferential direction of the outer circumference of the installation clamp column, and a plurality of limiting recesses adapted to the limiting protrusions are provided in the copper sleeve installation groove.

[0020] Furthermore, an insulating sheet is provided on the bottom plate.

[0021] Compared with the prior art, the beneficial effects of the present invention are at least in the following aspects:

[0022] 1. The utility model optimizes the structure of the brushless motor, so that the layout between the rotor assembly, the stator assembly, and the bearing structure is more reasonable and compact, which helps to reduce the looseness and vibration between the parts and improve the stability of the overall structure; in addition, the turntable and the copper sleeve structure are optimized respectively, and the design of the round cover turntable and the copper sleeve in the rotor assembly and the copper sleeve mounting groove and the mounting clamp in the stator assembly makes the alignment between the rotor and the stator more accurate; and the design of the limiting outer ring, the limiting inner ring, and the limiting groove can effectively control the relative position of the rotor and the stator, so that the rotor rotation stability is higher and the concentricity of the motor is greatly improved; the overall use of few connecting parts reduces the looseness of the connecting parts when the rotor rotates, eliminates the vibration and noise caused by the connection of multiple parts during operation, and has higher output accuracy, better concentricity, higher precision, and is conducive to miniaturization of the structure;

[0023] 2. Furthermore, the bearing structure and copper sleeve structure of the utility model are cleverly designed. By designing a bearing mounting portion on the inner wall of the copper sleeve and combining the use of an axial seal, the upper or lower part of the bearing structure can be respectively acted on by adsorption or compression to prevent axial separation during rotation, thereby reducing the axial clearance and providing a simpler and more effective axial positioning, which helps to reduce the axial displacement caused by vibration or external forces, improve the operating stability of the equipment, and avoid additional complex structures and maintenance costs. At the same time, the coaxial arrangement and positioning of the bearing and the copper sleeve can make the overall structure rotate at high speed and smoothly, further improving the concentricity of rotation, and meeting the application of thin products with high-precision output and high requirements for noise reduction.

[0024] 3. The utility model has reasonable overall design, low manufacturing cost, long service life, good economic benefits and is suitable for large-scale promotion. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram of the overall structure of a compact brushless motor in Embodiment 1 of the present utility model;

[0026] Figure 2 This is a schematic diagram of the overall structure of the compact brushless motor of Example 1 of the utility model;

[0027] Figure 3 This is a schematic cross-sectional view of the overall structure of the compact brushless motor of Embodiment 1 of the present utility model;

[0028] Figure 4 This is a schematic diagram of the overall structure of the turntable of the brushless motor with a compact structure in Example 1 of the utility model;

[0029] Figure 5 This is a schematic cross-sectional view of the overall structure of the turntable of the brushless motor with a compact structure in Embodiment 1 of the utility model;

[0030] Figure 6 This is a schematic diagram of the overall structure of the copper sleeve of the brushless motor with a compact structure in Example 1 of the utility model;

[0031] Figure 7 This is a schematic cross-sectional view of the overall structure of the copper sleeve of the brushless motor with a compact structure in Embodiment 1 of the utility model;

[0032] Figure 8 This is a schematic diagram of the overall structure of a compact brushless motor in Embodiment 2 of the present utility model;

[0033] Fig. 9 This is a schematic diagram of the overall structure of the compact brushless motor of Example 2 of the utility model;

[0034] Fig.10 This is a schematic cross-sectional view of the overall structure of a compact brushless motor according to Embodiment 2 of the present utility model;

[0035] Fig.11 This is a schematic diagram of the overall structure of the turntable of the brushless motor with a compact structure in Example 2 of the utility model;

[0036] Fig.12 This is a schematic cross-sectional view of the overall structure of the turntable of the brushless motor with a compact structure according to the second embodiment of the utility model;

[0037] Fig.13 This is a schematic diagram of the overall structure of the copper sleeve of the brushless motor with a compact structure in Example 2 of the utility model;

[0038] Fig.14 This is a schematic cross-sectional view of the overall structure of the copper sleeve of the brushless motor with a compact structure according to Example 2 of the utility model.

[0039] In the figure:

[0040] 1. Rotor assembly; 11. Turntable; 111. Position-limiting outer ring; 1111. Outer bevel; 112. Position-limiting inner ring; 1121. Inner bevel; 113. Cavity; 114. Second groove; 12. Casing; 13. Magnetic ring; 14. Copper sleeve; 141. Position-limiting groove; 142. Core mounting portion; 143. Mounting column; 1431. Position-limiting protrusion; 144. Upper bearing mounting portion; 145. Lower bearing mounting portion ; 146. First groove; 147. Axial blind hole; 2. Stator assembly; 21. Bottom plate; 211. Copper sleeve mounting groove; 212. Limiting recess; 22. Stator core; 23. Circuit board; 24. Axis; 3. Bearing structure; 31. Upper bearing; 32. Lower bearing; 33. Flexible oil absorber; 4. Upper seal; 5. Lower seal; 6. Magnetic gasket; 7. Axial gasket; 8. Brake gasket; 9. Insulating sheet. DETAILED DESCRIPTION

[0041] In order to facilitate the understanding of the utility model, the technical scheme and advantages of the utility model are further described in detail in combination with the accompanying drawings and embodiments. The specific structure and characteristics of the utility model are described in the following by way of example, which should not constitute any limitation to the utility model. At the same time, any of the technical features mentioned below (including implicit or disclosed), as well as any technical features directly displayed or implied in the figure, can continue to be arbitrarily combined or deleted between these technical features, so as to form more other embodiments that may not be directly or indirectly mentioned in the utility model. The preferred implementation of the utility model is shown in the accompanying drawings. However, the utility model can be implemented in many different forms and is not limited to the implementation described herein.

[0042] In the description of the present invention, unless otherwise specified, the terms "bottom", "upper", "lower", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0043] Example 1

[0044] like Figure 1-7 As shown, this embodiment 1 provides a brushless motor with a compact structure, which is applied to imaging devices such as cameras, and includes:

[0045] The rotor assembly 1 includes a dome-shaped turntable 11, a housing 12, a magnetic ring 13, and a copper sleeve 14; the housing 12 is arranged below the turntable 11; the bottom of the turntable 11 is provided with a limit outer ring 111 and a limit inner ring 112 protruding toward the copper sleeve 14; the housing 12 is sleeved on the limit outer ring 111; the magnetic ring 13 is arranged on the inner periphery of the housing 12, and is spaced apart from the end of the limit outer ring 111; specifically, the spacing between the magnetic ring and the end of the limit outer ring refers to a gap between the upper end of the magnetic ring and the lower end of the limit outer ring to avoid interference. The outer periphery of the copper sleeve 14 is provided with a limit groove 141 adapted to the limit inner ring 112;

[0046] The stator assembly 2 includes a base plate 21, a stator core 22, a circuit board 23, and an axis 24; the copper sleeve 14 is embedded in the copper sleeve mounting groove 211 through the mounting column 143, and the axis 24 is penetrated through the inner cavity of the copper sleeve 14 and extends upward to the outside of the copper sleeve 14; the top of the turntable 11 is sleeved on the outer periphery of one end of the axis 24 extending to the outside of the copper sleeve 14; the outer periphery of the copper sleeve 14 is radially concave with a core mounting portion 142, and the stator core 22 is sleeved on the core mounting portion 142; in this embodiment, the integrated core mounting portion is arranged on the outer periphery of the copper sleeve to better fix the stator core, reduce the use of fixing parts, and energize the stator core to drive the magnetic ring to drive the casing and the turntable to rotate.

[0047] Specifically, in this embodiment, the stator core 22 includes a composite enameled wire and a silicon steel sheet group, and its configuration and working principle can refer to the prior art, which will not be elaborated here; the circuit board 23 is bonded and arranged below the bottom plate 21; specifically, in this embodiment 1, the circuit board 23 can be bonded and arranged below the bottom plate 21 by adhesive in the prior art;

[0048] The bearing structure 3 is located inside the copper sleeve 14 and sleeved on the outer periphery of the shaft center 24; an upper seal 4 and a lower seal 5 are respectively disposed on the upper and lower parts of the bearing structure 3.

[0049] To be further detailed, a cavity 113 matching the outer diameter of the copper sleeve 14 is provided on the inner side of the turntable 11, and the edge of the cavity 113 extends downward to form the limiting inner ring 112; the upper part of the copper sleeve 14 extends into the cavity 113, and the limiting groove 141 is opposite to the gap of the limiting inner ring 112; specifically, the limiting groove 141 is opposite to the gap of the limiting inner ring 112, which means that a slight gap is left between the end of the limiting inner ring 112 and the notch of the limiting groove 141.

[0050] Preferably, the side walls of the limiting outer ring 111 and the limiting inner ring 112 that are close to each other are respectively provided with an outer inclined surface 1111 and an inner inclined surface 1121 that are inclined in opposite directions. In this embodiment, the design of the limiting outer ring, the limiting inner ring and the limiting groove can effectively control the relative position of the rotor and the stator, making the rotor more stable in rotation and greatly improving the concentricity of the motor;

[0051] Preferably, a copper sleeve installation groove 211 for installing the copper sleeve 14 is provided at the center of the bottom plate 21; a mounting post 143 matching the copper sleeve installation groove 211 is provided on the copper sleeve 14; the copper sleeve 14 is embedded in the copper sleeve installation groove 211 through the mounting post 143. To further improve its installation stability, a plurality of limiting protrusions 1431 are provided at intervals along the circumference of the outer periphery of the mounting post 143, and a plurality of limiting recesses 212 matching the limiting protrusions 1431 are provided in the copper sleeve installation groove 211.

[0052] Preferably, the bearing structure 3 includes an upper bearing 31 and a lower bearing 32; the inner wall of the copper sleeve 14 is provided with an upper bearing 31 mounting portion 144 and a lower bearing 32 mounting portion 145 respectively adapted to the upper bearing 31 and the lower bearing 32; the ends of the upper bearing 31 and the lower bearing 32 close to each other are respectively in contact with the upper bearing 31 mounting portion 144 and the lower bearing 32 mounting portion 145. In this embodiment, the upper bearing mounting portion and the lower bearing mounting portion formed in one piece in the copper sleeve are used to mount the upper bearing and the lower bearing, which, on the one hand, better ensures the coaxiality of the two bearings and greatly improves the concentricity of the utility model; on the other hand, it eliminates the problems such as vibration and noise caused by the connection of multiple components during operation, and the motor output accuracy is higher; at the same time, it is more conducive to improving the overall rotation flatness of the utility model, which is conducive to integrated processing and prolongs its service life.

[0053] In this embodiment, the upper bearing and the lower bearing are both roller bearings, and their working principles and installation methods can refer to the existing technology and will not be described in detail here.

[0054] To further improve the rotational stability, preferably, the upper seal 4 is a wire retaining ring arranged on the top of the upper bearing 31; the lower seal 5 is a corrugated washer arranged at the bottom of the lower bearing 32; in this way, by using an axial retaining ring, when the utility model is installed and locked with other components of the imaging device, the upper bearing and the lower bearing are simultaneously pressed onto the integrated bearing mounting portion of the copper sleeve, which can eliminate the vibration and noise problems caused by the bearing assembly gap; the bearing structure is coaxially arranged and positioned, so that the overall structure can rotate at high speed and smoothly.

[0055] Preferably, an insulating sheet 9 is provided on the bottom plate 21. In this embodiment, the circuit board 23 is an SMT circuit board or a PCB circuit board. At the same time, an insulating sheet is provided between the bottom plate and the copper sleeve to improve the safety of use.

[0056] Example 2

[0057] like Figure 8-14 As shown, this embodiment 2 provides a brushless motor with a compact structure, which can be applied to imaging devices such as projectors and cameras. The main differences between this embodiment 2 and embodiment 1 are:

[0058] The bearing structure 3 is an oil-containing bearing, and a flexible oil-absorbing member 33 is provided between the outer periphery of the oil-containing bearing and the inner wall of the copper sleeve 14. In this embodiment, the flexible oil-absorbing member can be a flexible member such as wool felt that can be used for absorbing lubricating oil. In other embodiments, other oil-absorbing members in the prior art that can achieve the same function can also be adopted, as long as they can meet the functions of the utility model.

[0059] Furthermore, a magnetic gasket 6 and an axial gasket 7 are arranged between the top of the copper sleeve 14 and the top of the inner side of the turntable 11; a first groove 146 for installing the magnetic gasket 6 is arranged on the top of the copper sleeve 14, and a second groove 114 for installing the axial gasket 7 is arranged on the top of the inner side of the turntable 11. In the present embodiment 2, an integrated oil-containing bearing is adopted, a wool oil absorber is arranged on the inner side of the copper sleeve, a stopper for convenient installation of the stator core is arranged on the outer periphery of the copper sleeve, the internal structure of the turntable is designed to cooperate with the stopper of the casing and the copper sleeve, and in addition, a magnetic gasket and an axial gasket that attract each other are arranged between the top of the copper sleeve and the turntable to prevent axial separation during rotation; the overall stability is higher, the rotation concentricity is better, the mute effect is better, and the practicality is stronger.

[0060] In addition, compared with mechanical stops or limit devices, magnetic adsorption provides simpler and more effective axial positioning, helping to reduce axial displacement caused by vibration or external forces, improving the operating stability of the equipment while avoiding additional complex structures and maintenance costs.

[0061] Furthermore, the upper seal 4 is an oil-stopping gasket arranged on the top of the oil-containing bearing; the lower seal 5 is a retaining ring arranged at the bottom of the bearing structure 3; the inner bottom of the copper sleeve 14 is provided with an axial blind hole 147, and a brake gasket 8 is arranged in the axial blind hole 147. In this embodiment, an oil-stopping gasket and a retaining ring are provided; the oil-stopping gasket can further prevent the oil of the bearing from overflowing during operation, and at the same time, the retaining ring is mainly used to prevent the axial displacement of the components during operation, resulting in the separation of the stator and the rotor; that is, in addition to the design of the magnetic gasket and the axial gasket, it is a structure that further eliminates the axial displacement, thereby better ensuring the rotation stability of the utility model.

[0062] It should be noted that the present invention also includes other elements or structures that can realize the function of a brushless motor. Other parts of the present invention not mentioned can refer to the prior art and will not be described in detail here.

[0063] The above-mentioned embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. For ordinary technicians in this field, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the attached claims and their equivalents.

Claims

1. A compact brushless motor, characterized in that: include: The rotor assembly comprises a dome-shaped turntable, a housing, a magnetic ring and a copper sleeve; the housing is arranged below the turntable; a limit outer ring and a limit inner ring protruding toward the copper sleeve are arranged at the bottom of the turntable; the housing is sleeved on the limit outer ring; the magnetic ring is arranged on the inner periphery of the housing and is spaced from the end of the limit outer ring; a limit groove matching the limit inner ring is arranged on the outer periphery of the copper sleeve; The stator assembly includes a bottom plate, a stator core, a circuit board, and an axis; the axis is inserted into the copper sleeve and extends upward to the outside of the copper sleeve; the top of the turntable is sleeved on the outer periphery of one end of the axis extending outside the copper sleeve; a core mounting portion is concavely provided radially inwardly on the outer periphery of the copper sleeve, and the stator core is sleeved on the core mounting portion; the circuit board is bonded and arranged under the bottom plate; A bearing structure is provided, wherein the bearing structure is located inside the copper sleeve and sleeved on the outer periphery of the shaft center; an upper sealing member and a lower sealing member are provided on the upper part and the lower part of the bearing structure respectively.

2. The compact brushless motor according to claim 1, characterized in that: A cavity matching the outer diameter of the copper sleeve is provided on the inner side of the rotating disk, and the edge of the cavity extends downward to form the limiting inner ring; the upper part of the copper sleeve extends into the cavity, and the limiting groove is opposite to the gap of the limiting inner ring.

3. The compact brushless motor according to claim 2, characterized in that: The side walls of the limiting outer ring and the limiting inner ring close to each other are respectively provided with an outer inclined surface and an inner inclined surface inclined in opposite directions.

4. The compact brushless motor according to claim 3, characterized in that: A copper sleeve installation groove for installing the copper sleeve is provided at the center of the bottom plate; a mounting clamping column matched with the copper sleeve installation groove is provided on the copper sleeve; and the copper sleeve is embedded and arranged on the bottom plate.

5. The compact brushless motor according to claim 4, characterized in that: The bearing structure comprises an upper bearing and a lower bearing; the inner wall of the copper sleeve is provided with an upper bearing mounting portion and a lower bearing mounting portion adapted to the upper bearing and the lower bearing respectively; the ends of the upper bearing and the lower bearing close to each other are respectively in contact with the upper bearing mounting portion and the lower bearing mounting portion.

6. The compact brushless motor according to claim 5, characterized in that: The upper sealing member is a steel wire retaining ring arranged on the top of the upper bearing; and the lower sealing member is a wave washer arranged on the bottom of the lower bearing.

7. The compact brushless motor according to claim 4, characterized in that: A relative magnetic gasket and an axial gasket are arranged between the top of the copper sleeve and the inner top of the turntable; a first groove for installing the magnetic gasket is arranged on the top of the copper sleeve, and a second groove for installing the axial gasket is arranged on the inner top of the turntable.

8. The compact brushless motor according to claim 7, characterized in that: The bearing structure is an oil-containing bearing, and a flexible oil-absorbing member is provided between the outer periphery of the oil-containing bearing and the inner wall of the copper sleeve.

9. The compact brushless motor according to claim 8, characterized in that: The upper seal is an oil-stopping gasket arranged on the top of the oil-containing bearing; the lower seal is a retaining ring arranged at the bottom of the bearing structure; an axial blind hole is arranged at the inner bottom of the copper sleeve, and a brake gasket is arranged in the axial blind hole.

10. The compact brushless motor according to claim 6, characterized in that: A plurality of limiting protrusions are arranged at intervals along the circumferential direction of the outer circumference of the installation clamp column, and a plurality of limiting recesses matched with the limiting protrusions are arranged in the copper sleeve installation groove.

Images