A stator assembly and a brush-type hollow cup motor comprising the same

Abstract

This utility model discloses a stator assembly and a brushed hollow cup motor including the stator assembly. The assembly includes a stator shaft with a central shaft hole, a front end cover at one end of the stator shaft, and a magnetic ring on the outer periphery of the stator shaft. The stator shaft is made of a magnetically conductive material, while the front end cover is made of a non-magnetically conductive material. The formed stator shaft is die-cast in a front end cover mold to form an integral stator base. The contact surface between the stator shaft and the front end cover has an axial limiting structure and a circumferential limiting structure. In this utility model, the stator shaft and the front end cover are made of different materials, which ensures smooth magnetic field flow inside the motor and prevents magnetic leakage at the ends. Simultaneously, the stator shaft and the front end cover are formed into an integral structure through die-casting, and the axial and circumferential limiting structures ensure the stability of their connection, preventing the stator shaft from detaching from the front end cover.

Description

Technical Field

[0001] This utility model relates to the field of motor design technology, and in particular to a stator assembly and a brushed hollow cup motor including the stator assembly. Background Technology

[0002] Currently, the front cover of brushed hollow cup motors is mostly an integrated structure (such as the front cover in patent number CN206117460U) or a press-fit structure (such as the front cover and magnet sleeve in patent number CN215498489U).

[0003] Because the integrated structure is formed in one piece, non-magnetic materials are usually used to prevent magnetic leakage at the ends. Therefore, there is a situation where the stator shaft (equivalent to the tubular bearing housing in patent number CN206117460U) is not magnetic. The non-magnetic stator shaft will affect the smooth passage of the magnetic field, resulting in excessive loss of motor performance.

[0004] Press-fit structures often use glue to fix the stator shaft (equivalent to the magnetic sleeve in patent number CN215498489U) to the front cover. Due to vibrations during motor operation, the stator shaft and front cover may fall off or rotate. Furthermore, the stator shaft has many processing steps and high process requirements, resulting in excessively high costs. Utility Model Content

[0005] To address the technical problems of significant performance loss or easy detachment of the stator shaft from the front end cover in existing brushed coreless motors, this utility model provides a stator assembly and a brushed coreless motor comprising the assembly to solve the aforementioned problems.

[0006] This utility model proposes a stator assembly, including a stator shaft with a central shaft hole, a front end cover located at one end of the stator shaft, and a magnetic ring located on the outer periphery of the stator shaft. The stator shaft is made of a magnetically conductive material, and the front end cover is made of a non-magnetically conductive material. The formed stator shaft is placed in a front end cover mold and die-cast to form an integral stator seat. The contact surface between the stator shaft and the front end cover has an axial limiting structure and a circumferential limiting structure.

[0007] In an optional embodiment of this utility model, the stator shaft includes a shaft segment and a disk segment located at one end of the shaft segment, the magnetic ring is connected to the shaft segment, and the disk segment is connected to the front end cover.

[0008] In an optional embodiment of this utility model, the axial limiting structure consists of a mutually cooperating annular groove and a convex ring.

[0009] In an optional embodiment of this utility model, the annular groove is located on the outer periphery of the disc segment, and the convex ring is located on the inner periphery of the front end cover.

[0010] In an optional embodiment of this utility model, the circumferential limiting structure consists of mutually cooperating grooves and protrusions, and one or more circumferential limiting structures are arranged along the circumferential direction.

[0011] In an optional embodiment of this utility model, the groove is located on the outer periphery of the disc segment and extends axially, while the protrusion is located on the inner periphery of the front end cover.

[0012] In an optional embodiment of this utility model, the inner circumference of the front end cover also has limiting bosses located at both ends of the disc segment, so that the disc segment is covered by the front end cover; the limiting boss located at the outer end of the stator shaft cooperates with the bearing.

[0013] In an optional embodiment of this utility model, the stator shaft is die-cast.

[0014] In an optional embodiment of this utility model, the magnetic ring and the disk segment are sandwiched between the two ends of one of the limiting bosses, and the inner circumferential surface of the limiting boss is connected to the shaft segment.

[0015] This utility model also proposes a brushed hollow cup motor, including the stator assembly described above.

[0016] The beneficial effects of this utility model are: (1) The stator shaft and the front cover of the stator assembly described in this utility model are made of different materials, which not only ensures the smooth magnetic field inside the motor, but also avoids magnetic leakage at the end. At the same time, the stator shaft and the front cover are formed into an integral structure by die casting process, and the axial and circumferential limiting is used to ensure the stability of the connection between the two, and to prevent the stator shaft and the front cover from falling off.

[0017] (2) In this utility model, the stator shaft and the front end cover are directly die-cast, which greatly reduces the cost and processing time.

[0018] (3) In this utility model, the disc segment at the end of the stator shaft is connected to the front cover, and the front and rear ends of the disc segment are blocked by the limiting boss. This can not only wrap the disc segment inside the front cover, making the connection between the stator shaft and the front cover tighter, but also achieve a good anti-magnetic leakage effect. Attached Figure Description

[0019] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0020] Figure 1 This is an exploded view of a specific embodiment of the brushed hollow cup motor described in this utility model; Figure 2 This is an internal sectional view of a specific embodiment of the brushed hollow cup motor described in this utility model; Figure 3 This is a schematic diagram of the stator base in the stator assembly described in this utility model; Figure 4 This is a perspective view of the stator shaft in the stator assembly described in this utility model; Figure 5 This is a schematic diagram of the front end cover in the stator assembly described in this utility model.

[0021] In the diagram, 1 is the stator base, 101 is the stator shaft, 1011 is the shaft segment, 1012 is the disc segment, 102 is the front end cover, 2 is the magnetic ring, 3 is the shaft hole, 4 is the groove, 5 is the protrusion, 6 is the bearing, 7 is the front limit boss, 8 is the rear limit boss, 9 is the rear end cover, 10 is the housing, 11 is the rotor assembly, 12 is the rotating shaft, 13 is the stator assembly, 14 is the annular groove, and 15 is the convex ring. Detailed Implementation

[0022] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0023] Example 1 like Figure 2 and Figure 3 As shown, a stator assembly includes a stator shaft 101 with a central shaft hole 3, a front end cover 102 located at one end of the stator shaft 101, and a magnetic ring 2 located on the outer periphery of the stator shaft 101. The stator shaft 101 is made of a magnetically conductive material, such as 20 steel, while the front end cover 102 is made of a non-magnetically conductive material, such as hard aluminum. The stator shaft 101 not only provides mechanical support for the magnetic ring 2, but also, since the stator shaft 101 is in direct contact with the point where the magnetic field of the magnetic ring is most concentrated, if the magnetic conductivity is not strong, the magnetic field strength will be greatly reduced. Therefore, the magnetic conductivity of the stator shaft 101 helps to concentrate the magnetic field energy and smoothly pass through to form a low-resistance magnetic circuit, thereby greatly improving the performance of the motor.

[0024] The stator shaft 101 is first manufactured independently. After molding, the stator shaft 101 is placed in the front cover mold and die-cast to form an integral stator seat 1. Since the two parts are manufactured sequentially rather than directly as a single piece, different materials can be used. The contact surface between the stator shaft 101 and the front cover 102 has an axial limiting structure and a circumferential limiting structure. The stator shaft 101 and the front cover 102 are die-cast together. Compared to traditional methods relying on glue or fasteners for fixation, the integral stator seat 1 in this invention has higher connection strength. Simultaneously, the axial and circumferential limiting structures can effectively limit and bear force during motor vibration, preventing breakage at the connection between the stator shaft 101 and the front cover 102, thus preventing them from separating.

[0025] Stator shaft 101: like Figure 3 As shown, the stator shaft 101 includes a shaft segment 1011 and a disk segment 1012 located at one end of the shaft segment 1011. The magnetic ring 2 is connected to the shaft segment 1011, and the disk segment 1012 is connected to the front end cover 102. The outer diameter of the disk segment 1012 is larger than the outer diameter of the shaft segment 1011. The axial limiting structure and the circumferential limiting structure are located on the disk segment 1012. Enlarging the cross-section of the disk segment 1012 can increase the contact area and improve the connection strength.

[0026] To reduce process costs and processing time, the stator shaft 101 is preferably formed by die casting.

[0027] Front cover 102: The front cover 102 extends axially, and the disc section 1012 of the stator shaft 101 is fixed to the rear half of the inner circumference of the front cover 102. The front half of the inner circumference of the front cover 102 is engaged with the bearing 6.

[0028] like Figures 3-5 As shown, the axial limiting structure may be, but is not limited to, a mutually cooperating annular groove 14 and a convex ring 15. The annular groove 14 and the convex ring 15 are respectively located on the contact surfaces of the disk segment 1012 and the front end cover 102. In this embodiment, the annular groove 14 is located on the outer periphery of the disk segment 1012, and the convex ring 15 is located on the inner periphery of the front end cover 102. The convex ring 15 is inserted into the annular groove 14.

[0029] like Figures 3-5 As shown, the circumferential limiting structure can be, but is not limited to, mutually cooperating grooves 4 and protrusions 5, and one or more circumferential limiting structures are arranged along the circumferential direction. The groove 4 is a non-annular structure, thus it can play a circumferential limiting role. In this embodiment, four grooves 4 are arranged in an array along the circumferential direction. The grooves 4 are located on the outer periphery of the disc segment 1012 and extend axially, while the protrusions 5 are located on the inner periphery of the front end cover 102. In a preferred embodiment, the groove 4 is an arc-shaped groove, and the protrusion 5 is also correspondingly arc-shaped. This can avoid stress concentration at the connection between the two and also increase the contact area.

[0030] Example 2 Based on Embodiment 1, the inner circumference of the front cover 102 also has limiting bosses located at both ends of the disk segment 1012, so that the disk segment 1012 is covered by the front cover 102; the limiting boss located at the outer end of the stator shaft 101 cooperates with the bearing 6. For ease of description, in this embodiment, the two limiting bosses are named the front limiting boss 7 and the rear limiting boss 8, respectively. The front limiting boss 7 abuts against the front end of the disk segment 1012, and the rear limiting boss 8 abuts against the rear end of the disk segment 1012. The bearing 6 is installed on the inner circumference of the front limiting boss 7.

[0031] Compared to Embodiment 1, in this embodiment, the front cover 102 and the stator shaft 101 are not connected to each other solely by the limiting structure on the circumferential surface, such as... Figure 3 As shown, the two limiting bosses can directly clamp the disc segment 1012 in the middle. When the motor vibrates, the limiting bosses can withstand a large bending force, avoiding the stator shaft 101 and the front cover 102 from breaking at the circumferential contact surface and causing them to separate.

[0032] In a further design, the magnetic ring 2 and the disk segment 1012 are sandwiched between the two ends of one of the limiting bosses, the inner circumferential surface of which is connected to the shaft segment 1011. For example... Figure 2 and Figure 3 As shown, the rear limiting boss 8 is located between the magnetic ring 2 and the disk segment 1012. The inner circumferential surface of the rear limiting boss 8 extends to the surface of the shaft segment 1011. On the one hand, it can play a role in structural stability. On the other hand, the rear limiting boss 8 is part of the front cover 102 and is also made of non-magnetic material. Therefore, the rear limiting boss 8 can completely shield the end of the magnetic ring 2 and prevent the magnetic field from leaking out from the disk segment 1012.

[0033] Example 3 A brushed coreless motor includes the stator assembly 13 described above. For example... Figure 1 As shown, the brushed hollow cup motor includes a rear end cover 9, a housing 10, a rotor assembly 11, a rotating shaft 12, and a stator assembly 13. The rotor assembly 11 is located on the outer periphery of the magnetic ring 2 of the stator assembly 13. The rear end cover 9, the stator assembly 13, and the housing 10 are fixed together. The rotating shaft 12 passes through the shaft hole 3 along the axial direction. The rotating shaft 12 is rotatably engaged with the rear end cover 9 and the front end cover 102 of the stator assembly 13 through the bearing 6.

[0034] Through the design of the stator assembly 13 described in this utility model, the brushed hollow cup motor not only improves its performance, but also reduces processing costs and greatly improves processing efficiency.

[0035] In this specification, the illustrative expressions of the terms do not necessarily refer to the same embodiments. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments.

[0036] Based on the above-described preferred embodiments of this utility model, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the technical concept of this utility model. The technical scope of this utility model is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A stator assembly, characterized in that: The stator shaft (101) includes a stator shaft (101) with a central shaft hole (3), a front end cap (102) located at one end of the stator shaft (101), and a magnetic ring (2) located on the outer periphery of the stator shaft (101). The stator shaft (101) is made of a magnetic material, and the front end cap (102) is made of a non-magnetic material. The formed stator shaft (101) is placed in the front end cap mold and die-cast to form an integral stator seat (1). The contact surface between the stator shaft (101) and the front end cap (102) has an axial limiting structure and a circumferential limiting structure.

2. The stator assembly according to claim 1, characterized in that: The stator shaft (101) includes a shaft segment (1011) and a disk segment (1012) located at one end of the shaft segment (1011). The magnetic ring (2) is connected to the shaft segment (1011), and the disk segment (1012) is connected to the front end cover (102).

3. The stator assembly according to claim 2, characterized in that: The axial limiting structure consists of a matching annular groove (14) and a convex ring (15).

4. The stator assembly according to claim 3, characterized in that: The annular groove (14) is located on the outer periphery of the disc segment (1012), and the convex ring (15) is located on the inner periphery of the front end cover (102).

5. The stator assembly according to claim 2, characterized in that: The circumferential limiting structure consists of a groove (4) and a protrusion (5) that cooperate with each other, and one or more circumferential limiting structures are arranged along the circumferential direction.

6. The stator assembly according to claim 5, characterized in that: The groove (4) is located on the outer periphery of the disk segment (1012) and extends axially, while the protrusion (5) is located on the inner periphery of the front cover (102).

7. The stator assembly according to claim 2, characterized in that: The inner circumference of the front cover (102) also has limiting bosses located at both ends of the disk segment (1012) so that the disk segment (1012) is covered by the front cover (102); the limiting boss located at the outer end of the stator shaft (101) cooperates with the bearing (6).

8. The stator assembly according to claim 1, characterized in that: The stator shaft (101) is die-cast.

9. The stator assembly according to claim 7, characterized in that: The magnetic ring (2) and the disk segment (1012) are sandwiched between the two ends of one of the limiting bosses, and the inner circumferential surface of the limiting boss is connected to the shaft segment (1011).

10. A brushed hollow cup motor, characterized in that: Includes the stator assembly (13) as described in any one of claims 1-9.

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