Split core with unequal tooth widths

Abstract

The utility model provides a kind of unequal tooth width split type iron core, including outer layer A iron core, inner layer B iron core and fastening support, all iron core teeth tooth width of A iron core is equal, outer circle closed slot is equipped on iron core tooth, all iron core teeth are integrally connected to form annular whole by outer circle closed slot;All iron core teeth tooth width of B iron core is equal, all iron core teeth are integrally connected to form annular whole by inner circle magnetic yoke;The iron core tooth of A iron core and B iron core is staggered and spaced arrangement, and the iron core tooth tooth width of A iron core and B iron core is unequal;A iron core and B iron core are made into double-layer split type unequal tooth width iron core structure by coaxial nesting, and the both ends of fastening support are respectively welded and fixed in A iron core inner wall and B iron core magnetic yoke outer wall.The utility model solves the problem of low slot fill factor, large torque fluctuation, large tooth slot torque and large noise of existing concentrated winding motor;Solve the problems of high single-tooth punching cost, poor reliability and other problems of split type iron core.

Description

Technical Field

[0001] This utility model relates to a split iron core with unequal tooth width, belonging to the field of motor technology, specifically to an iron core that can effectively reduce motor cogging torque, improve motor slot fill factor, and enhance manufacturability. Background Technology

[0002] With the increasing application of concentrated winding motors in robotics and electric motorcycles, higher requirements are being placed on the motor's high slot fill factor, cogging torque, noise reduction, automated production process, and reliability. Motor noise originates from two sources: mechanical operating noise and electromagnetic noise, with electromagnetic noise accounting for a larger proportion. Electromagnetic noise is typically caused by higher-order electromagnetic forces. In the early stages of motor design, noise reduction can be achieved by reducing motor torque fluctuations, cogging torque, and increasing stator stiffness (increasing slot fill factor).

[0003] Conventional integrated iron cores employ a concentrated winding structure using round copper wire (round type). The iron core is either wound or stacked. Due to the limitations of the integrated iron core structure, the maximum slot fill factor for machine winding can reach approximately 50% to 55%. If a tooth-yoke separated iron core structure is used, the slot fill factor for round or flat copper wire can reach 70% to 75%. However, concentrated windings are generally used in high-torque applications, resulting in a large number of teeth and coils. The cost is high after stamping and stacking individual teeth, and the cogging torque is relatively large. This type of winding is mostly suitable for products with low requirements for torque fluctuation and noise, such as some industrial motors, a few white goods, and low-speed electric motorcycle motors. Therefore, improving the slot fill factor and reducing motor torque fluctuation and noise are of great significance.

[0004] Currently, most concentrated winding motors adopt an integrated or split concentrated winding core structure. Among them, the integrated round wire motor has the disadvantage of large torque fluctuation, low slot fill factor, and excessive second air gap due to the limitation of parallel tooth size. The split concentrated winding core adopts a single tooth stamping and stacking, which has the problems of high manufacturing cost and low production efficiency.

[0005] In the prior art, Chinese Patent CN118137695A discloses a self-locking iron core with a separable toothed yoke, a motor, and a manufacturing process. This process uses a toothed yoke separation structure, where each tooth needs to be stamped before being stacked. The stamping of the teeth results in significant waste of silicon steel sheets at the edges and corners, leading to low production efficiency and requiring multiple stacking operations. It also requires high dimensional accuracy for each tooth, resulting in low production efficiency and a low pass rate, making automated production difficult. Chinese Patent CN119582500A discloses a high slot fill rate concentrated flat wire winding layout structure with equal cross-sectional area, which uses a toothed yoke separation semi-closed slot structure. However, compared to the fully closed slot structure of this patent, the semi-closed slot requires separate stamping of teeth at the axial slot openings before stacking. In addition, unequal width copper wires are used to improve the slot fill rate. From a practical process perspective, the production process is complex, the production efficiency is low, and it is almost impossible to achieve actual production. Utility Model Content

[0006] To solve the above-mentioned technical problems, this utility model provides a split iron core with unequal tooth width. The split iron core with unequal tooth width can improve the reliability of the motor, reduce the material cost and process cost of the motor, and facilitate automated production.

[0007] This utility model is achieved through the following technical solution.

[0008] This utility model provides a split iron core with unequal tooth width, comprising an outer A iron core, an inner B iron core, and a fastening bracket. All the iron core teeth of the A iron core have equal tooth widths and are provided with outer circular closed grooves. All the iron core teeth are integrally connected through the outer circular closed grooves to form a ring. All the iron core teeth of the B iron core have equal tooth widths and are integrally connected through an inner circular magnetic yoke to form a ring. The iron core teeth of the A iron core and the B iron core are arranged alternately, and the tooth widths of the iron core teeth of the A iron core and the B iron core are unequal. The A iron core and the B iron core are coaxially nested to form a double-layer split iron core structure with unequal tooth widths, and the two ends of the fastening bracket are respectively welded and fixed to the inner wall of the A iron core and the outer wall of the B iron core magnetic yoke.

[0009] The mating surfaces of the A core and the B core are provided with an axial clearance.

[0010] The B core has auxiliary grooves at the ends of its core teeth, forming an unequal height pole shoe structure.

[0011] Both core A and core B are integrally formed by stacking or winding silicon steel sheets, or by molding soft magnetic composite materials.

[0012] The copper wire coils are pre-wound and fitted onto the core teeth of core A and core B from opposite axial directions. Then, core A and core B are pressed together by a press.

[0013] This structure is suitable for motors with concentrated windings.

[0014] The beneficial effects of this utility model are: it solves the problems of low slot fill factor, large torque fluctuation, large cogging torque, and high noise in existing centralized winding motors; and it solves the problems of high cost and poor reliability of single-tooth stamping of split iron cores. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of this utility model;

[0016] Figure 2 This is a cross-sectional view of the present invention;

[0017] Figure 3 This is a schematic diagram of the core gap of this utility model;

[0018] Figure 4 This is a schematic diagram of the structure of the B-core of this utility model;

[0019] Figure 5 This is a schematic diagram of the coil being properly inserted into the teeth of the B-core iron core of this utility model;

[0020] Figure 6 This is a schematic diagram of the structure of the A-core of this utility model;

[0021] Figure 7 This is a schematic diagram of the coil being reverse-inserted onto the iron core teeth of the A-core of this utility model;

[0022] Figure 8 This is a schematic diagram of the structure of the auxiliary groove of this utility model;

[0023] Figure 9 This is a schematic diagram of the structure of the outer circular closed groove of this utility model;

[0024] Figure 10 This is a structural schematic diagram of the fastening bracket of this utility model. Detailed Implementation

[0025] The technical solution of this utility model is further described below, but the scope of protection is not limited to what is described.

[0026] like Figures 1-10As shown, for a concentrated winding motor, this utility model provides a split closed-slot iron core structure with unequal tooth widths and reversible coil windings. This structure includes an outer A core, an inner B core, and a fastening bracket. All the teeth of the A core have equal tooth widths and are provided with outer circular closed slots. All the teeth are integrally connected through these outer circular closed slots to form a ring. All the teeth of the B core have equal tooth widths and are integrally connected through an inner circular yoke to form a ring. The teeth of the A and B cores are arranged alternately, and the tooth widths of the A and B cores are unequal. The A and B cores are coaxially nested to form a double-layer split unequal tooth width iron core structure, and the two ends of the fastening bracket are welded and fixed to the inner wall of the A core and the outer wall of the B core yoke, respectively.

[0027] The mating surfaces of the A core and the B core are provided with an axial gap to ensure that the air gap magnetic flux density of the motor will not be significantly reduced.

[0028] The B core has an auxiliary groove at the end of the core tooth to form an unequal height pole shoe structure, which solves the problem of excessive magnetic leakage caused by using an outer circular closed groove.

[0029] Both the A core and the B core are integrally formed by stacking or winding silicon steel sheets, or by molding soft magnetic composite materials (such as SMC soft magnetic composite materials).

[0030] Preferably, the outer circular closed groove is suitable for iron core winding, eliminating the step of stamping and stacking the laminations, thus greatly improving material utilization and production efficiency.

[0031] Furthermore, the unequal tooth width combined with the outer circular closed slot structure can reduce the motor's cogging torque and torque fluctuation. The outer circular closed slot structure is suitable for core winding, eliminating the step of stamping and stacking laminations, which greatly improves material utilization and production efficiency. At the same time, by continuously adjusting the tooth width of core A and core B, the copper wire coil can be wound and placed into the core teeth of core A and core B from the positive and negative directions, ultimately pressing the two cores into one, maximizing the motor slot fill factor, and improving the motor's manufacturing process and reliability.

[0032] Specifically, the fastening bracket can ensure reliable cooperation between iron core A and iron core B, solving the problem of unreliable connection in the toothed yoke separation structure.

[0033] This structure is suitable for motors with concentrated windings.

[0034] The beneficial effects of this utility model are as follows:

[0035] 1. By adopting an A and B iron core with unequal tooth width structure, the coil is pre-wound and then reversed, which solves the problem of low slot fill factor in conventional concentrated winding motors, reduces motor cogging torque and torque fluctuation, and ultimately reduces noise.

[0036] 2. By adjusting the fit of the two tooth widths, the full coverage of the copper wire slots in the motor can be maximized, thereby improving the overall rigidity of the iron core, reducing the contact thermal resistance of the iron core, improving the heat dissipation capacity of the motor, and further reducing the operating noise of the motor.

[0037] 3. The A and B split iron core structure is adopted. The A iron core is integrated by the outer circle closed groove design, and the B iron core is integrated by the inner circle magnetic yoke design. Both iron cores can realize the winding structure, which solves the problems of complex single-punch stacking process, high single tooth machining accuracy requirements and low reliability of conventional tooth yoke separated structure iron core, and can effectively reduce the cogging torque of motor.

Claims

1. A split core with unequal tooth widths, characterized by: The structure includes an outer A core, an inner B core, and a fastening bracket. All the teeth of the A core have equal tooth widths and are provided with outer circular closed grooves. All the teeth are integrally connected through the outer circular closed grooves to form a ring. All the teeth of the B core have equal tooth widths and are integrally connected through an inner circular magnetic yoke to form a ring. The teeth of the A and B cores are arranged alternately and the tooth widths of the A and B cores are unequal. The A and B cores are coaxially nested to form a double-layered split unequal tooth width core structure, and the two ends of the fastening bracket are welded and fixed to the inner wall of the A core and the outer wall of the B core magnetic yoke, respectively.

2. The split core of unequal tooth widths as recited in claim 1, wherein: The mating surfaces of the A core and the B core are provided with an axial clearance.

3. The split core of unequal tooth widths as recited in claim 1, wherein: The B core has auxiliary grooves at the ends of its core teeth, forming an unequal height pole shoe structure.

4. The split core of unequal tooth widths as recited in claim 1, wherein: Both core A and core B are integrally formed by stacking or winding silicon steel sheets, or by molding soft magnetic composite materials.

5. The split core of unequal tooth widths as recited in claim 1, wherein: The copper wire coils are pre-wound and fitted onto the core teeth of core A and core B from opposite axial directions. Then, core A and core B are pressed together by a press.

6. The split core of claim 1 to 5, wherein: This structure is suitable for motors with concentrated windings.

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