A mounting structure for a brushless motor rotor

Abstract

This invention relates to an installation structure for a brushless motor rotor, comprising a rotor with a through-hole at its center for axially mounting a steel shaft onto the rotor; a magnet, fitted around the outer periphery of the rotor; and an elastic limiting structure surrounding the shaft hole on the rotor. The elastic limiting structure includes a limiting side and an elastic side arranged circumferentially, which together form an elastic limiting channel coaxial with the shaft hole. The limiting side is formed on a limiting claw, limiting the steel shaft radially; the elastic side is formed on an elastic claw, which can bend and deform relative to the shaft hole to create a dynamic gap between the elastic side and the steel shaft. The advantages of this invention are: by providing an elastic limiting structure, while maintaining the coaxiality of the steel shaft and rotor, dynamic gap compensation eliminates the gap between the rotor and the steel shaft in real time, maintaining dynamic contact with the steel shaft, avoiding radial wobble of the rotor and rigid collision with the steel shaft, and reducing the mechanical noise of the motor.

Description

Technical Field

[0001] This invention relates to the field of motor technology, and in particular to a mounting structure for a brushless motor rotor. Background Technology

[0002] In internal rotor brushless motors, the outer casing typically serves as the stator, while the internal components and the main shaft constitute the rotor assembly. During operation, the rotor assembly rotates, while the outer casing, acting as the stator, is fixed to the motor frame.

[0003] However, in existing brushless motors, the rotor is typically mounted on a steel shaft with a clearance fit, meaning there is a gap between the rotor and the steel shaft. Under this assembly relationship, when the rotor rotates under the magnetic force of the stator, it will be deflected, causing the wall of the rotor's central shaft hole to strike the steel shaft, generating noise. Summary of the Invention

[0004] To address the aforementioned problems in the prior art, this invention provides a mounting structure for a brushless motor rotor.

[0005] The above-mentioned problems of the present invention are solved by the following technical solutions:

[0006] A mounting structure for a brushless motor rotor, comprising,

[0007] The rotor has a through shaft hole at its center for axially mounting a steel shaft onto the rotor.

[0008] A magnet is fitted onto the outer circumference of the rotor and drives the rotor to rotate synchronously around axis L;

[0009] An elastic limiting structure is provided on the rotor around the shaft hole;

[0010] The elastic limiting structure includes a limiting side and an elastic side arranged circumferentially, and the limiting side and the elastic side together form an elastic limiting channel coaxial with the shaft hole.

[0011] The limiting side is formed on the limiting claw to limit the steel shaft in the radial direction; the elastic side is formed on the elastic claw, which can be bent and deformed relative to the shaft hole to create a dynamic gap between the elastic side and the steel shaft.

[0012] A further provision of the above technical solution is that the limiting claw is integrally formed on the rotor, and the rotors have at least two connection points;

[0013] The two connection points and the limiting side are arranged in a triangular structure when projected onto the same plane.

[0014] A further configuration of the above technical solution is as follows: the limiting claw includes a gripper with an arc-shaped cross-section, the gripper extending along the axis L; a limiting wall is radially formed on the back of the gripper; a first connecting point is provided on the gripper, and a second connecting point is provided on the limiting wall.

[0015] A further provision of the above technical solution is that: an elastic groove is axially provided on the rotor, and the shaft hole is formed at the bottom of the elastic groove; the gripper extends axially from the bottom of the elastic groove.

[0016] The first connecting point on the gripper is connected to the bottom of the groove, and the second limiting point on the limiting wall is connected to the groove wall of the elastic groove.

[0017] A further provision of the above technical solution is that the outer wall of the gripper and the bottom of the groove are connected by an arc-shaped concave surface.

[0018] A further feature of the above technical solution is that the limiting wall and the gripper have the same length along the axis L.

[0019] A further provision of the above technical solution is that: the elastic claw is also integrally formed on the rotor, and the first end of the elastic claw along the axis L direction is connected to the bottom of the groove; the elastic side is the arc-shaped surface on the elastic claw facing the steel shaft.

[0020] The elastic claw and the limiting claw have the same length along the axis L.

[0021] A further provision of the above technical solution is that: both the elastic side and the limiting side have inclined guide surfaces at their ends away from the shaft hole, and multiple guide surfaces surround to form a constricted inlet for inserting the steel shaft.

[0022] A further provision of the above technical solution is that the total number of the elastic claw and the limiting claw is at least three.

[0023] A further provision of the above technical solution is that: a clamping curved surface is provided on the elastic side and the limiting side, and the clamping curved surface is axially connected to the guide surface.

[0024] Compared with the prior art, the beneficial effects of the present invention are as follows: by setting up an elastic limiting structure, while maintaining the coaxiality of the steel shaft and the rotor, the gap between the rotor and the steel shaft is eliminated in real time through dynamic gap compensation, and the rotor is kept in dynamic contact with the steel shaft, avoiding the radial wobble of the rotor and the rigid collision with the steel shaft, thus reducing the mechanical noise of the motor. Attached Figure Description

[0025] Figure 1 This is an exploded structural diagram of the present invention.

[0026] Figure 2This is a schematic diagram of the structure of the present invention.

[0027] Figure 3 This is a radial cross-sectional view of the rotor.

[0028] Figure 4 This is an isometric sectional view of the rotor.

[0029] Figure 5 This is a schematic diagram of the rotor.

[0030] Figure 6 This is an axial cross-sectional view of the rotor.

[0031] The attached diagram is labeled as follows: 100, rotor; 101, shaft hole; 110, limiting claw; 120, elastic claw; 111, gripper; 112, limiting wall; 111.1, limiting side; 121, elastic side; 130, output teeth; 102, groove bottom; 103, groove wall; 104, elastic groove; 105, arc-shaped concave surface; 1, magnet; 2, steel shaft; a, first connection point; b, second connection point; c, guide surface; d, clamping curved surface. Detailed Implementation

[0032] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided below.

[0033] like Figure 1-6 As shown, this embodiment discloses a mounting structure for a brushless motor rotor.

[0034] include,

[0035] The rotor 100 has a through shaft hole 101 at its center for mounting the steel shaft 2 axially onto the rotor 100.

[0036] Magnet 1 is fitted onto the outer periphery of rotor 100 and drives rotor 100 to rotate synchronously around axis L;

[0037] An elastic limiting structure is provided on the rotor 100 around the shaft hole 101;

[0038] The elastic limiting structure includes a limiting side 111.1 and an elastic side 121 arranged circumferentially, and the limiting side 111.1 and the elastic side 121 together form an elastic limiting channel coaxial with the shaft hole 101.

[0039] The limiting side 111.1 is formed on the limiting claw 110 and limits the steel shaft 2 in the radial direction; the elastic side 121 is formed on the elastic claw 120, and the elastic claw 120 can be bent and deformed relative to the shaft hole 101 so that there is a dynamic gap between the elastic side 121 and the rotating shaft.

[0040] The above is the basic scheme of this embodiment.

[0041] Specific reference Figure 1 and Figure 2 As shown, in this embodiment, the rotor 100, magnet 1, and steel shaft 2 are arranged coaxially, with their central axes completely overlapping. The steel shaft 2 extends axially through the entire interior of the rotor 100 and maintains a clearance fit with the shaft hole 101 of the rotor 100, ensuring relative rotation between them. The magnet 1 is configured as a ring structure and is mounted on the outer circumferential surface of the rotor 100 through a limiting structure, forming a complete magnetic pole array. When the rotor 100 begins to rotate under the action of the stator magnetic field, the steel shaft 2 remains stationary due to its fixed installation, thus generating relative rotational motion between the rotor 100 and the steel shaft 2.

[0042] During continuous operation of the rotor 100, due to the combined effects of periodically changing electromagnetic and centrifugal forces, the rotor 100 will experience radial swaying of a certain amplitude. To prevent this swaying from causing a violent collision between the inner wall of the rotor 100 and the outer surface of the steel shaft 2, this embodiment features an elastic limiting structure specifically designed around the outer periphery of the steel shaft 2. This elastic limiting structure is integrated with the rotor 100 body, thus enabling it to rotate synchronously with the rotor 100. The purpose of the elastic limiting structure is to effectively reduce the clearance between the steel shaft 2 and the rotor 100, and more importantly, to provide elastic buffering when the rotor 100 sways, significantly reducing the impact force and frequency between the rotor 100 and the steel shaft 2, thereby greatly reducing the mechanical noise generated during equipment operation.

[0043] In this embodiment, the elastic limiting structure includes a limiting side 111.1 that directly contacts the outer surface of the steel shaft 2 and an elastic side 121. The limiting side 111.1, through its rigidity, limits the radial position of the steel shaft 2, effectively ensuring a strict concentricity between the steel shaft 2 and the rotor 100. The elastic side 121, through the elastic deformation capability of the elastic claw 120, maintains a tight contact with the outer wall of the steel shaft 2. When the rotor 100 experiences slight radial wobble during high-speed rotation, the elastic side 121 undergoes a corresponding radial displacement along with the movement of the steel shaft 2. This displacement creates a dynamically variable gap between the elastic side 121 and the outer wall of the steel shaft 2. Due to the elastic recovery characteristics of the elastic claw 120 material, the elastic side 121 maintains continuous contact with the outer wall of the steel shaft 2. This elastic contact, combined with the rigid constraint of the limiting side 111.1, forms a radial clamping force on the steel shaft 2. Through this ingenious dual-action mechanism, the system can eliminate any possible dynamic gaps in real time, ensuring that the rotor 100 will not wobble in the clamped state.

[0044] Based on the above settings, the dynamic stability of rotor 100 during high-speed operation is significantly improved, while the vibration frequency during motor operation is effectively reduced, thereby improving the operating accuracy and service life of the entire transmission system.

[0045] Specifically, the limiting claw 110 is integrally formed on the rotor 100, and the rotors 100 have at least two connection points;

[0046] The two connection points and the limiting side 111.1 are arranged in a triangular structure when projected onto the same plane.

[0047] Specific reference Figure 4 As shown, this embodiment fully utilizes the highly stable mechanical properties of a triangular structure, designing the limiting claw 110 to connect to the rotor 100 via two independent connection points. When projected axially, these two fixed connection points, along with any selected portion on the limiting side 111.1 surface, will inevitably form a complete triangle. This three-point planar arrangement not only ensures the connection strength of the limiting claw 110 on the rotor 100, providing stable limiting support for the steel shaft 2 and guaranteeing the coaxiality between the steel shaft 2 and the rotor 100, but also effectively prevents displacement or deformation of the steel shaft 2 relative to the rotor 100 during operation through the stability principle of the triangle, thereby greatly improving the reliability and durability of the entire mechanical system.

[0048] In this embodiment, the limiting claw 110 includes a gripper 111 with an arc-shaped cross-section, the gripper 111 extending along the axis L; a limiting wall 112 is radially formed on the back of the gripper 111; a first connecting point a is provided on the gripper 111, and a second connecting point b is provided on the limiting wall 112.

[0049] Preferably, in this embodiment, the radial cross-section of the limiting claw 110 is set to an approximately T-shaped structure, which can effectively enhance its mechanical properties. Specifically, the first connecting point a is arranged in the axial direction of the limiting claw 110, while the second connecting point b is arranged in the radial direction. Through this spatial arrangement, a stable triangular support structure is naturally formed between the limiting claw 110 and the limiting side 111.1. This triangular structure has excellent mechanical properties and can significantly improve the stability and load-bearing capacity of the overall device.

[0050] As a preferred embodiment, both the first connecting point a and the second connecting point b adopt a surface connection design. This large-area contact connection can effectively disperse stress and avoid local stress concentration. At the same time, the shape of the first connecting point a is completely consistent with the radial cross-section of the gripper 111, which greatly improves the tightness of the fit between the components, thereby further enhancing the reliability and service life of the entire mechanism.

[0051] In this embodiment, in order to protect the elastic limiting structure and prevent it from being interfered with by components in the external space, the rotor 100 is provided with an elastic groove 104 axially, and the shaft hole 101 is formed in the bottom 102 of the elastic groove 104; the gripper 111 extends axially from the bottom 102 of the elastic groove 104.

[0052] The first connecting point a on the gripper 111 is connected to the bottom of the groove 102, and the second limiting point on the limiting wall 112 is connected to the groove wall 103 of the elastic groove 104.

[0053] Preferably, the elastic limiting structure is completely disposed and accommodated within the internal space of the elastic groove 104, and its overall structure does not exceed the boundary range of the elastic groove 104. In this embodiment, the elastic groove 104 is formed on the first side end face of the rotor 100, and an opening structure for easy assembly is formed on this side end face. At the same time, an output tooth 130 for power transmission is formed on the second side end face of the rotor 100. The elastic limiting structure is specifically formed in the bottom region of the elastic groove 104, and its main body extends from the bottom 102 of the groove towards the opening direction. This design ensures both the limiting function and the compactness of the structure.

[0054] To ensure the connection strength and reliability of the limiting claw 110 in actual operation, in this embodiment, the outer end of the limiting wall 112 in the radial direction is connected to the groove wall 103 of the elastic groove 104. That is to say, the limiting wall 112 maintains a stable connection with the rotor 100 body throughout its entire length extension direction. This full-length connection design significantly improves the integrity and load-bearing capacity of the structure.

[0055] Preferably, in this embodiment, the outer wall of the gripper 111 and the bottom of the groove 102 are connected by an arc-shaped concave surface 105.

[0056] Specific reference Figure 3 As shown, the cross-sectional design of the gripper 111 adopts an arc-shaped structure, specifically, its outer wall presents an outwardly convex arc-shaped surface. This arc-shaped outer wall is connected to the groove bottom 102 through an inwardly recessed transition area. Based on this design, the convex arc-shaped outer wall and the recessed transition surface form a continuous and smooth stress transmission path, which can effectively disperse external loads. At the same time, this structure significantly enhances the overall support strength and deformation resistance of the gripper 111. When the gripper 111 is subjected to external forces, this optimized design can effectively suppress the generation of bending deformation, thereby ensuring that the gripper 111 always maintains stable limiting performance and avoids functional failure due to deformation.

[0057] Preferably, in this embodiment, the limiting wall 112 and the gripper 111 have the same length along the axis L.

[0058] Based on this configuration, in this embodiment, the design of the limiting wall 112 provides stable and reliable support for the gripper 111 at any position along its length, and this support extends throughout the entire working stroke of the gripper 111. In other words, the limiting wall 112 can form a uniform distribution of support force on the entire limiting side 111.1 of the gripper 111, thereby effectively ensuring the concentricity accuracy between the limiting side 111.1 and the shaft hole 101. This support mechanism not only prevents the gripper 111 from shifting or deforming during operation, but also ensures that the gripper 111 receives consistent support at all positions along its length, thereby improving the stability and accuracy of the entire clamping system.

[0059] Preferably, in this embodiment, the limiting wall 112 is connected to the middle of the outer wall of the gripper 111.

[0060] In this embodiment, the elastic claw 120 is specifically configured as follows: the elastic claw 120 is also integrally formed on the rotor 100, and the first end of the elastic claw 120 along the axis L direction is connected to the groove bottom 102; the elastic side 121 is the arc-shaped surface on the elastic claw 120 facing the steel shaft 2.

[0061] The elastic claw 120 and the limiting claw 110 have the same length along the axis L.

[0062] Preferably, in this embodiment, the elastic claw 120 and the gripper 111 maintain the same overall structural design. This allows the elastic side 121 formed on the elastic claw 120 and the limiting side 111.1 formed on the limiting claw 110 to be joined together to form a complete clamping space.

[0063] Based on the above configuration, the elastic claw 120 and the limiting claw 110 can generate a uniformly distributed clamping force when clamping the steel shaft 2, thereby ensuring that the magnitude and direction of the force on the steel shaft 2 at each contact point remain consistent. This uniform force distribution effectively avoids problems such as positional displacement or shape deformation of the steel shaft 2 that may be caused by uneven local force distribution, significantly improving the stability and reliability of the clamping process.

[0064] In this embodiment, the outer wall of the elastic claw 120 and the bottom of the groove 102 are also connected by an arc-shaped concave surface 105.

[0065] In this embodiment, in order to facilitate the smooth installation of the steel shaft 2, inclined guide surfaces c are provided on the ends of the elastic side 121 and the limiting side 111.1 that are away from the shaft hole 101, and multiple guide surfaces c surround to form a constricted inlet for the steel shaft 2 to be inserted.

[0066] Reference Figure 5 As shown, the guide surface c is arranged on one side of the open end of the elastic groove 104, and its structure is a gradually narrowing conical shape along the insertion direction of the steel shaft 2. This structural design provides effective guidance for the installation process of the steel shaft 2. Through the conical narrowing structure of the guide surface c, it can be ensured that the steel shaft 2 maintains the correct movement trajectory during insertion, and is ultimately accurately positioned coaxially with the elastic groove 104. This guiding structure not only simplifies the installation operation, but also improves the assembly accuracy and reliability, allowing the steel shaft 2 to be smoothly inserted into the predetermined position without deviation or jamming.

[0067] To ensure contact between the limiting side 111.1, the elastic side 121, and the steel shaft 2, in this embodiment, the elastic side 121 and the limiting side 111.1 are provided with a clamping curved surface d, which is axially connected to the guide surface c.

[0068] Preferably, the minimum inner diameter of the clamping curved surface d is smaller than the diameter of the steel shaft 2.

[0069] Specific reference Figure 6As shown, a clamping surface d is connected to the constricted end of the guide surface c. The clamping surface d has a radially convex shape of a continuous arc bulging towards the center, creating a progressive clamping effect. Specifically, at least one specific clamping point is provided on the clamping surface d, and the inner diameter of the clamping space formed at the clamping point is smaller than the actual diameter of the steel shaft 2. As the steel shaft 2 is gradually inserted along the guide surface c, as the shaft advances, once it reaches the predetermined position in the clamping space, the outer surface of the steel shaft 2 exerts a radially outward pushing force on the clamping surface d. This interaction force causes the clamping surface d to elastically deform and expand outward, thus ensuring that the clamping point maintains continuous and stable close contact with the outer surface of the steel shaft 2 while maintaining a certain contact pressure, forming a reliable clamping effect.

[0070] Preferably, in this embodiment, the total number of the elastic claw 120 and the limiting claw 110 is at least three.

[0071] In this embodiment, at least one limiting claw 110 and one elastic claw 120 are provided. The three claws form a stable three-point contact system on the outer circumference of the steel shaft 2. When these claws contact the outer circumferential surface of the steel shaft 2, reliable mechanical contact points are formed at three different locations on the steel shaft 2. Utilizing the inherent stability principle of triangular geometry, the geometric characteristic of defining a plane by three points allows the entire limiting elastic structure to generate a uniformly distributed radial clamping force on the steel shaft 2. This multi-claw cooperative design not only improves the reliability of clamping but also ensures that the steel shaft 2 receives balanced constraint force in all radial directions, thereby achieving precise control and stable fixation of the radial position of the steel shaft 2.

[0072] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A mounting structure of a brushless motor rotor, comprising, a rotor (100) provided with a through shaft hole (101) in the center for mounting a steel shaft (2) to the rotor (100) in the axial direction; a magnet (1) sleeved on the outer periphery of the rotor (100) and driving the rotor (100) to rotate synchronously around the axis L; characterized in that an elastic limiting structure is arranged around the shaft hole (101) on the rotor (100); the elastic limiting structure comprises a limiting side (111.1) and an elastic side (121) arranged in the circumferential direction, which together form an elastic limiting channel coaxial with the shaft hole (101); the limiting side (111.1) is formed on a limiting claw (110) and limits the steel shaft (2) in the radial direction; the elastic side (121) is formed on an elastic claw (120), which can be deformed to make the elastic side (121) and the steel shaft (2) have a dynamic gap.

2. The mounting structure of a brushless motor rotor according to claim 1, characterized by: the limiting claw (110) is integrally formed on the rotor (100), and the rotor (100) has at least two engagement points; the projections of the two engagement points and the limiting side (111.1) on the same plane are arranged in a triangular structure.

3. The mounting structure of a brushless motor rotor according to claim 2, characterized by: the limiting claw (110) comprises a clamping claw (111) with an arc-shaped cross section, which extends along the axis (L); the back of the clamping claw (111) is radially formed with a limiting wall (112); the clamping claw (111) is provided with a first engagement point (a), and the limiting wall (112) is provided with a second engagement point (b).

4. The mounting structure of a brushless motor rotor according to claim 3, characterized by: an elastic groove (104) is arranged axially on the rotor (100), and the shaft hole (101) is formed on the groove bottom (102) of the elastic groove (104); the clamping claw (111) extends axially from the groove bottom (102) of the elastic groove (104); the first engagement point (a) on the clamping claw (111) engages with the groove bottom (102), and the second engagement point (b) on the limiting wall (112) engages with the groove wall (103) of the elastic groove (104).

5. The mounting structure of a brushless motor rotor according to claim 4, characterized by: the outer wall of the clamping claw (111) and the groove bottom (102) are connected by an arc-shaped concave surface (105).

6. The mounting structure of a brushless motor rotor according to claim 3, characterized by: the length of the limiting wall (112) and the clamping claw (111) in the direction of the axis L is consistent.

7. The mounting structure of a brushless motor rotor according to claim 4, characterized by: the elastic claw (120) is also integrally formed on the rotor (100), and the first end of the elastic claw (120) in the direction of the axis (L) engages with the groove bottom (102); the elastic side (121) is an arc surface on the side of the elastic claw (120) facing the steel shaft (2); the length of the elastic claw (120) and the limiting claw (110) in the direction of the axis (L) is consistent.

8. The mounting structure of a brushless motor rotor according to claim 1 or 7, characterized by: The elastic side (121) and the limiting side (111.1) are provided with inclined guide surfaces (c) at the end away from the shaft hole (101), and a plurality of guide surfaces (c) are enclosed to form a necked guide entrance for the steel shaft (2) to be inserted.

9. The mounting structure of a brushless motor rotor according to claim 1, characterized by: The total number of the elastic claws (120) and the limiting claws (110) is at least three.

10. The mounting structure of a brushless motor rotor according to claim 8, characterized by: The elastic side (121) and the limiting side (111.1) are provided with a clamping curved surface (d) which is connected to the guide surface (c) in the axial direction.

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