Rotor core rounding device, rotor core, and rounding method

Abstract

The application relates to the field of electric machines, and discloses a rotor core rounding device, a rotor core and a rounding method. The rotor core rounding device comprises a rounding assembly, the rounding assembly comprises a rotating base capable of rotating around an axis thereof, and a plurality of rounding fixing members uniformly and spacedly fixed to the outer periphery of the rotating base along the circumferential direction of the rotating base, and an iron core slot for inserting an iron core unit is formed between two adjacent rounding fixing members; one of the iron core slots is a starting iron core slot, the starting iron core slot is configured to be capable of limiting the starting iron core unit inserted therein along the circumferential direction and the radial direction of the rotating base; when the rotor core is in a flat state and the starting iron core unit is inserted into the starting iron core slot, the rotating base can rotate around the axis thereof to sequentially insert the remaining iron core units into the remaining iron core slots along the circumferential direction of the rotating base, so that the rotor core is switched from the flat state to the round state, the rounding efficiency of the rotor core can be improved, and the production cost is reduced.

Description

Technical Field

[0001] This invention relates to the field of motor technology, and in particular to a rotor core forming device, a rotor core, and a method for forming a round core. Background Technology

[0002] The rotor structure of an internal rotor motor includes a rotor core and magnets. A commonly used rotor core has multiple fan-shaped core units that are independently distributed along its circumference. Each core unit includes multiple fan-shaped rotor laminations that are stacked along the rotor core axis. When assembling the rotor structure, the rotor core is usually assembled first, and then the magnets are inserted between two adjacent core units along the rotor core axis. Finally, the rotor core and magnets are connected as one unit by injection molding using thermoplastic material.

[0003] However, all the rotor laminations in the aforementioned rotor core are independent of each other, and the processing of fan-shaped rotor laminations has the drawbacks of high waste and low material utilization. Therefore, related technologies have proposed chain rotor cores. Chain rotor cores have multiple core units distributed circumferentially, and adjacent core units are connected by external magnetic bridges. When assembling chain rotor cores, the chain rotor laminations are first assembled into a chain semi-finished product that extends in a straight line, and then the chain semi-finished product is rolled into a circular chain rotor core. Currently, the method of forming a circular chain rotor core is generally as follows: one end of the chain rotor core is hung on the positioning pin of the core mold through a buckle or positioning hole, and then the external magnetic bridges between adjacent core units are bent segment by segment along the circumferential direction. The external magnetic bridges are bent one by one, so that the core unit wraps around the outer ring of the core mold; after the chain rotor core is rounded, the outer clamp is closed and radially pressed to control the outer diameter, and then the ends of the chain rotor core are snapped together and welded. This method of forming a circle involves many steps and has low efficiency, leaving room for improvement. Summary of the Invention

[0004] The first technical problem solved by this invention is to provide a rotor core rounding device that can improve the rounding efficiency of rotor cores and reduce production costs.

[0005] The second technical problem solved by the present invention is to provide a rotor core that can improve the rounding efficiency of the rotor core and reduce production costs.

[0006] The third technical problem solved by this invention is to provide a method for forming a rotor core into a circle, which can improve the efficiency of forming the rotor core into a circle and reduce production costs.

[0007] The first technical problem mentioned above is solved by the following technical solution:

[0008] A rotor core forming device is provided. The rotor core is a chain-type core, comprising multiple core units connected in sequence. The rotor core has a straight state and a circular state. When the rotor core is in a straight state, the multiple core units are arranged in a straight line along a first direction. The core unit at one end of the rotor core in the first direction is the starting core unit. When the rotor core is in a circular state, a mounting groove for mounting permanent magnets is formed between two adjacent core units.

[0009] The rotor core forming device includes a rolling assembly, which includes a rotating base capable of rotating about its own axis and a plurality of rolling fixing members that are evenly spaced around the outer periphery of the rotating base along the circumference of the rotating base. A core slot is formed between two adjacent rolling fixing members for inserting the core unit. The core slot is provided in a one-to-one correspondence with the core unit, and the core slot can limit the core unit inserted into the core slot along the circumference of the rotating base.

[0010] One of the core slots is a starting core slot, which is configured to limit the starting core unit inserted therein at least along the circumferential and radial directions of the rotating base.

[0011] When the rotor core is in the straight state and the starting core unit is inserted into the starting core slot, the rolling assembly can rotate around the axis of the rotating base to insert the remaining core units into the remaining core slots along the circumference of the rotating base, so that the rotor core changes from the straight state to the circular state.

[0012] The rotor core rounding device of the present invention has the following advantages compared with the prior art:

[0013] The rotor core rounding device provided by this invention utilizes a starting core slot to limit the insertion of the initial core unit along the circumferential and radial directions of the rotating base. This prevents the initial core unit from wobbling during the rounding process of the chain rotor core, ensuring a better rounding effect. Then, the rolling assembly is controlled to rotate around the axis of the rotating base. During this rotation, the rolling assembly winds the rotor core, allowing the remaining core units to be inserted sequentially into the remaining core slots along the circumference of the rotating base. This transforms the rotor core from a straight to a circular state. Furthermore, because the core slot limits the insertion of the core unit along the circumference of the rotating base, the core unit cannot detach from the slot radially, ensuring the stability of the rounded rotor core. This eliminates the need for clamps to hold the rounded rotor core, simplifying the rounding process, improving rounding efficiency, and reducing production costs.

[0014] In one embodiment, the rolled fastener forms an outer circular surface along the sidewall of the rotating base that is radially away from the axis of the rotating base. The distance between two adjacent outer circular surfaces along the circumference of the rotating base is L11, and the dimension of the outer circular surface along the circumference of the rotating base is L12.

[0015] The core unit has two core sidewalls arranged opposite each other along the circumference of the rotor core. The rotor core in the circular state satisfies the following: the maximum distance between the two core sidewalls of the core unit along the circumference of the rotor core is L21, and the mounting slots are arranged parallel to each other along the circumference of the rotor core with a distance of L22.

[0016] L11>L21, L22>L12, L11+L12=L21+L22.

[0017] In one embodiment, the starting core unit is provided with an inner magnetic bridge at one end near the axis of the rotor core, and the inner magnetic bridge is provided with a rolled-out limiting fit portion protruding from one end along the circumference of the rotating base.

[0018] The number of the coiled fixing parts is 2P, where P is the number of pole pairs of the motor; the 2P coiled fixing parts are divided into one first coiled fixing part and 2P-1 second coiled fixing parts; along the rotation direction of the rotating base, the first coiled fixing part and the second coiled fixing part located downstream and adjacent to it form the starting iron core groove.

[0019] A rolling limiting groove is provided at the junction of the first rolling fixing member and the rotating base. The opening of the rolling limiting groove is connected to the starting iron core groove, and the rolling limiting groove is provided to pass through the first rolling fixing member along the axial direction of the rotating base.

[0020] The rolled-up limiting fitting part can be inserted into the rolled-up limiting groove along the axial direction of the rotating base, so that the inner magnetic bridge can be limited to the rolled-up limiting groove along the radial direction of the rotating base.

[0021] In one embodiment, the outer peripheral wall of the rotating base between two adjacent rolling fixing members forms an inner splicing surface, which is a plane perpendicular to the radial direction of the rotating base; the inner splicing surface can abut against the inner magnetic bridge of the core unit along the radial direction of the rotating base.

[0022] In one embodiment, along the radial direction of the rotating base, the groove sidewall of the roll-up limiting groove near the axis of the rotating base is located on the same plane as the inner circular surface that forms the starting iron core groove.

[0023] In one embodiment, the outer circular surface is a plane perpendicular to the radial direction of the rotating base, and the outer circular surface can abut against the outer magnetic bridge of the rotor core along the radial direction of the rotating base.

[0024] In one embodiment, the inner magnetic bridge has a circular profile surface on its side facing the axis of the core unit along the radial direction of the core unit.

[0025] The second rolling fixing member has a rolling guide surface on one of the two side walls that are arranged opposite each other along the circumference of the rotating base, and the side wall facing the same rotation direction as the rotating base has a rolling guide surface that is in contact with the inner rounding surface; the rolling guide surface can slide with the rounded contour surface.

[0026] In one embodiment, the rolling guide surface is an arc surface, and the axis of the rolling guide surface is parallel to the axis of the rotating base and both are located on the first plane;

[0027] The rotor core in a circular state satisfies the following: the inner side of the outer magnetic bridge is recessed and provided with an internal stress relief groove, the internal stress relief groove is symmetrically arranged about a second plane extending radially along the rotor core and about the axis of the rotor core, the outer magnetic bridge is symmetrically arranged about the second plane; the inner wall of the internal stress relief groove intersects the second plane at a first axis, the distance between the first axis and the axis of the rotor core is R1; the circular profile surface is an arc surface with the first axis as the central axis and a radius of R2.

[0028] The distance between the axis of the rolled guide surface and the axis of the rotating base is equal to R1, and the radius of the rolled guide surface is greater than or equal to R2.

[0029] In one embodiment, of the two sidewalls of the rolling fastener that are arranged opposite to each other along the circumference of the rotating base, the sidewall facing the opposite direction of rotation of the rotating base is a first limiting sidewall; the first limiting sidewall includes a first contact surface, which can abut against the core unit in the opposite direction of the rotation.

[0030] Of the two sidewalls of the first rolled fixing member that are arranged opposite each other along the circumference of the rotating base, the sidewall facing the same direction of rotation is the second limiting sidewall, and the second limiting sidewall includes a second contact surface; the second contact surface can abut against the core unit along the rotation direction of the rotating base.

[0031] In one embodiment, the first limiting sidewall includes at least two first contact surfaces arranged radially spaced along the rotating base. The first limiting sidewall satisfies the following: two adjacent first contact surfaces are connected by a first clearance surface, and the first clearance surface is recessed into the rolling fixing member along the circumference of the rotating base.

[0032] And / or, the second limiting sidewall includes at least two second contact surfaces arranged radially spaced along the rotating base, the second limiting sidewall satisfying that: two adjacent second contact surfaces are connected by a second clearance surface, the second clearance surface being recessed into the rolled fixing member along the circumference of the rotating base.

[0033] In one embodiment, the two side walls of the first rolled-up fixing member, which are arranged opposite each other along the circumference of the rotating base, are connected to the outer rounded surface through a first chamfered surface;

[0034] The second rolled-circle fixing member has two side walls that are arranged opposite each other along the circumference of the rotating base, and the side wall facing the opposite direction of rotation is connected to the outer round surface through the second chamfered surface;

[0035] Either the first chamfered surface or the second chamfered surface satisfies the following: in a plane perpendicular to the axial direction of the rotating base, the length of the orthographic projection of the chamfered surface is L0, L0 > (D1 - D2) / 6, where D1 is the maximum outer diameter of the rotor core and D2 is the minimum inner diameter of the rotor core; the included angle between the chamfered surface and the connected outer circular surface is α, α > 270 / P.

[0036] In one embodiment, the rotor core rounding device further includes:

[0037] A guide platform is located at one end of the rolling assembly along the first direction. The guide platform is used to keep the plurality of core units not inserted into the core slots in a straight state and to guide the movement of the portion of the rotor core in the straight state along the first direction; the first direction is perpendicular to the axial direction of the rotating base.

[0038] A driving component, the output end of which is connected to the rotating base, is used to drive the rolling component to rotate around the axis of the rotating base, so as to switch the rotor core from the straight state to the circular state.

[0039] In one embodiment, the guide platform is provided with a guide channel extending along a first direction, and the guide channel is provided through one end in the first direction to form an iron core outlet;

[0040] The guide channel has two limiting groove walls arranged opposite each other along the second direction. The portion of the rotor core in a straight state can be limited between the two limiting groove walls along the second direction and can move within the guide channel along the first direction. The axial direction, the first direction, and the second direction of the rotating base are perpendicular to each other.

[0041] In the second position, the rolling assembly is located outside the guide channel at one end of the core outlet along the first direction, and is positioned opposite to the core outlet along the first direction.

[0042] The second technical problem mentioned above is solved by the following technical solution:

[0043] The rotor core is switched from a straight state to a circular state using the rotor core forming device provided in any of the above embodiments.

[0044] The rotor core includes a plurality of core units arranged in sequence. The rotor core in the circular state satisfies the following: two adjacent core units are spaced apart, and any other two adjacent rotor cores are connected by an external magnetic bridge. The external magnetic bridge is located at one end of the core unit along the radial direction of the rotor core away from the rotor core axis to form a chain core.

[0045] The outer magnetic bridge can be bent and deformed so that the rotor core can switch from a straight state to a circular state; when the rotor core is in a straight state, multiple core units are arranged in a straight line along a first direction; when the rotor core is in a circular state, a mounting groove for mounting permanent magnets is formed between two adjacent core units.

[0046] Along the radial direction of the rotor core, an inner magnetic bridge is provided at one end of the core unit near the axis of the rotor core; along the radial direction of the core unit, the side of the inner magnetic bridge facing the axis of the core unit has a circular profile surface.

[0047] The inner side of the outer magnetic bridge is recessed and has an internal stress relief groove. The internal stress relief groove is symmetrically arranged about the second plane containing the axis of the rotor core. The outer magnetic bridge is symmetrically arranged about the second plane. The inner wall of the internal stress relief groove intersects the second plane at a first axis, which is parallel to the axis of the rotor core. The circular profile surface is an arc surface with the first axis as its central axis.

[0048] Compared with the prior art, the rotor core rounding device of the present invention has the following advantages:

[0049] The rotor core provided by the present invention sets the circular profile surface as an arc surface with the first axis as the central axis. During the process of the rotor core switching from a flat state to a circular state, the circular profile surface and the circular guide surface of the rotor core circularization device are slidably engaged to guide the core unit, thereby improving the circularization accuracy when the rotor core is switched from a flat state to a circular state using the rotor core circularization device.

[0050] In one embodiment, an external stress relief groove is provided in the outer recess of the external magnetic bridge. The external stress relief groove is symmetrically arranged about the second plane, and the inner wall of the groove of the external magnetic bridge intersects with the second plane.

[0051] In one embodiment, along the radial direction of the core unit, the side of the inner magnetic bridge facing the axis of the core unit also has a limiting profile surface that connects with the circular profile surface.

[0052] The limiting profile surface is a plane perpendicular to the radial direction of the rotor core, and the limiting profile surface can abut against the inner circular surface of the rotor core forming device along the radial direction of the rotor core.

[0053] The third technical problem mentioned above is solved by the following technical solution:

[0054] The method for forming a circular rotor core involves using the rotor core forming device provided in any of the above embodiments to switch the rotor core provided in any of the above embodiments from a flat state to a circular state; the method for forming a circular rotor core includes the following steps:

[0055] When the rotor core is in a straight state, the starting core unit is inserted into the starting core slot along the axial direction of the rotating base;

[0056] The rolling assembly is controlled to rotate around the axis of the rotating base, so that the remaining core units are sequentially inserted into the remaining core slots along the circumference of the rotating base, thereby switching the rotor core from the straight state to the circular state.

[0057] The rotor core rounding method described in this invention has the following advantages compared with the prior art:

[0058] When the rotor core is in a straight state, the starting core unit is inserted into the starting core slot along the axial direction of the rotating base; then the rolling assembly is controlled to rotate around the axis of the rotating base, so that each core unit is sequentially inserted into each core slot along the radial direction of the rotating base, thus changing the rotor core from a straight state to a circular state, completing the circular assembly of the rotor core. The circular assembly efficiency of the rotor core is high, which helps to reduce the production cost of the rotor core.

[0059] In one embodiment, the rotor core forming device includes a guide platform, and the guide platform is provided with a guide channel;

[0060] When the rotor core is in a straight state, inserting the starting core unit into the starting core slot along the axial direction of the rotating base also includes the following steps:

[0061] All other core units are placed in the guide channel and limited to the two limiting groove walls of the guide channel along the second direction. The rolling limiting fitting part on the starting core unit is inserted into the rolling limiting groove on the rolling assembly along the axial direction of the rotating base. Attached Figure Description

[0062] Figure 1 A schematic diagram of the rotor core in a flat state provided in an embodiment of the present invention;

[0063] Figure 2 A schematic diagram of the structure of a rotor core in a circular state provided in an embodiment of the present invention;

[0064] Figure 3 An axial schematic diagram of a rotor core in a circular state provided for an embodiment of the present invention;

[0065] Figure 4 An axial schematic diagram of a permanent magnet installed on a rotor core in a circular state, provided for an embodiment of the present invention;

[0066] Figure 5 A diagram showing the positional relationship between the rotor core forming device and the rotor core in a straight state when the starting core is inserted into the starting core slot, as provided in an embodiment of the present invention (guide platform not shown).

[0067] Figure 6 for Figure 5 A magnified view of a portion of point A in the middle;

[0068] Figure 7 A schematic diagram of the first structure (guide platform not shown) showing the rotor core forming device and the rotor core in a circular state provided in an embodiment of the present invention.

[0069] Figure 8 for Figure 7 A magnified view of a portion of point B in the middle;

[0070] Figure 9 A schematic diagram of the second structure (guide platform not shown) showing the rotor core forming device and the rotor core in a circular state provided in an embodiment of the present invention.

[0071] Figure 10 This is an axial schematic diagram of the rotor core rounding device provided in an embodiment of the present invention;

[0072] Figure 11 for Figure 10 A magnified view of a portion of point C in the middle;

[0073] Figure 12 for Figure 3 A magnified view of a portion of point D in the middle;

[0074] Figure 13 A schematic diagram of the first structure (shown as a guide platform) of the rotor core forming device and the rotor core in a straight state cooperating when the starting iron core is inserted into the starting iron core slot, according to an embodiment of the present invention.

[0075] Figure 14 A schematic diagram of the second structure (shown as a guide platform) showing the cooperation between the rotor core rounding device and the rotor core in a straight state when the starting iron core is inserted into the starting iron core slot, as provided in an embodiment of the present invention.

[0076] Label Explanation:

[0077] 10. Core forming device; 11. Rotating base; 111. Inner rounding surface; 12. Rolling fixing component; 121. Outer rounding surface; 122. First limiting sidewall; 1221. First contact surface; 1222. First clearance surface; 123. Second chamfered surface; 12a. First rolling fixing component; 12a1. Second limiting sidewall; 12a11. Second contact surface; 12a12. Second clearance surface; 12a2. First chamfered surface; 12b. Second rolling fixing component; 12b1. Rolling guide surface; 13. Rolling limiting groove; 14. Core groove; 14a. Starting core groove; 14b. Non-starting groove; 15. Guide platform; 151. Guide channel; 1511. Core outlet; 1512. Limiting groove wall;

[0078] 20. Rotor core; 21. Core unit; 210. Core sidewall; 21a. Starting core unit; 21b. Non-starting core unit; 211. Inner magnetic bridge; 2110. Rolled-out limiting mating part; 2111. Circular profile surface; 2112. Limiting profile surface; 212. Outer magnetic bridge; 2121. Inner stress relief groove; 2122. Outer stress relief groove; 213. Mounting groove;

[0079] 30. Permanent magnet;

[0080] 100, First plane; 200, Second plane. Detailed Implementation

[0081] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0082] In the description of this invention, it should be understood that the terms "center", "upper", "lower", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0083] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0084] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0085] like Figures 1 to 4As shown, an embodiment of the present invention provides a rotor core 20, which includes a plurality of core units 21 connected in sequence. The rotor core 20 is a chain core, which has a straight state and a circular state. When the chain core is in the straight state, the plurality of core units 21 are arranged in a straight line along a first direction. The core unit 21 at one end of the rotor core 20 in the first direction is the starting core unit 21a. When the chain core is in the circular state, a mounting groove 213 for mounting a permanent magnet 30 is formed between two adjacent core units 21.

[0086] Specifically, the circular rotor core 20 satisfies the following conditions: two adjacent core units 21 are spaced apart, and any other two adjacent core units 21 are connected by an external magnetic bridge 212. The external magnetic bridge 212 is located at the end of the core unit 21 along the radial direction of the rotor core 20 away from the axis of the rotor core 20, forming a chain-like core. It should be noted that in this chain-like core, along the radial direction of the rotor core 20, the ends of two adjacent core units 21 near the axis of the rotor core 20 are spaced apart circumferentially along the rotor core 20, so that when the external magnetic bridge 212 bends and deforms, the rotor core 20 can switch from a straight state to a circular state.

[0087] For example, the core unit 21 is generally fan-shaped, and the permanent magnet 30 is arranged parallel to the two side walls of the rotor core 20 that are opposite to each other in the circumference. In other words, the permanent magnet 30 is generally a rectangular block, so that the mounting groove 213 is a rectangular groove that runs through the rotor core 20 in the axial direction. The permanent magnet 30 is inserted into the mounting groove 213 in the axial direction of the rotor core 20, and the permanent magnet 30 is sandwiched between the two opposite side walls of the mounting groove 213 in the circumference of the rotor core 20, so as to limit the permanent magnet 30 in the circumference of the rotor core 20. The permanent magnet 30 abuts against the outer magnetic bridge 212 radially outward along the rotor core 20. The core unit 21 is provided with an inner magnetic bridge 211 at one end of the rotor core 20 radially close to the axis of the rotor core 20. The permanent magnet 30 abuts against the inner magnetic bridge 211 radially inward along the rotor core 20, so that the permanent magnet 30 is sandwiched between the inner magnetic bridge 211 and the outer magnetic bridge 212 radially along the rotor core 20, thereby limiting the permanent magnet 30 radially along the rotor core 20.

[0088] It should be noted that the rotor core 20 includes multiple rotor laminations stacked sequentially along the axis. Each rotor lamination includes multiple fan-shaped lamination bodies. At least some of the rotor laminations are chain laminations, with multiple lamination bodies connected sequentially. All the rotor laminations are stacked sequentially along the axis and fixed together to form multiple core units 21 arranged in a straight line along the first direction, thus obtaining a rotor core 20 in a flat state. The structure of the chain laminations and how to fix all the rotor laminations together to obtain a rotor core 20 in a flat state are existing technologies in the art and will not be described in detail here.

[0089] like Figures 1 to 4 As shown, in some embodiments, the rotor core 20 in a circular state satisfies the following: the inner side of the outer magnetic bridge 212 is recessed with an inner stress relief groove 2121, the inner stress relief groove 2121 is symmetrically arranged about the second plane 200 about the axis of the rotor core 20, and the outer magnetic bridge 212 is symmetrically arranged about the second plane 200; the inner wall of the inner stress relief groove 2121 intersects the second plane 200 at the first axis.

[0090] The aforementioned internal stress relief groove 2121 makes the outer magnetic bridge 212 easy to bend and deform, which facilitates the rotor core 20 to switch from a straight state to a circular state. Moreover, during this process, the outer magnetic bridge 212 bends and deforms around the first axis.

[0091] For example, the internal stress relief groove 2121 is an arc-shaped groove, and the axis of the internal stress relief groove 2121 is located in the second plane 200 and parallel to the first axis.

[0092] In some embodiments, an external stress relief groove 2122 is recessed on the outer side of the outer magnetic bridge 212. The external stress relief groove 2122 is symmetrically arranged about the second plane 200, and the inner wall of the groove of the outer magnetic bridge 212 intersects the second plane 200. This arrangement makes the outer magnetic bridge 212 more prone to bending deformation, and during the process of the rotor core 20 changing from a straight state to a circular state, the outer magnetic bridge 212 bends and deforms around the first axis.

[0093] For example, the external stress relief groove 2122 is an arc-shaped groove, and the axis of the external stress relief groove 2122 is located in the second plane 200 and parallel to the first axis.

[0094] Embodiments of the present invention also provide a rotor core forming device for switching the rotor core 20 from a straight state to a circular state. For ease of description below, the core unit 21 at one end of the rotor core 20 in the first direction when it is in a straight state is referred to as the starting core unit 21a.

[0095] like Figures 3 to 11 As shown, the rotor core forming device includes a rolling assembly, which includes a rotating base 11 that can rotate around its own axis and a plurality of rolling fixing members 12 that are evenly spaced around the outer periphery of the rotating base 11 along the circumference. A core slot 14 is formed between two adjacent rolling fixing members 12 for inserting a core unit 21. The core slot 14 is arranged in a one-to-one correspondence with the core unit 21, and the core slot 14 can limit the core unit 21 inserted into the core slot 14 along the circumference of the rotating base 11.

[0096] Specifically, the rolled fixing member 12 extends radially along the rotating base 11. One end of the rolled fixing member 12 near the axis of the rotating base 11 is fixed to the outer peripheral wall of the rotating base 11. Along the circumference of the rotating base 11, the ends of two adjacent rolled fixing members 12 away from the axis of the rotating base 11 form the outer opening of the core groove 14. The outer opening of the core groove 14 is provided through the axial direction of the rotating base 11, so that the core unit 21 can be inserted into the core groove 14 from the outer opening.

[0097] One of the core slots 14 is the starting core slot 14a, which is configured to limit the insertion of the starting core unit 21a along the circumference and radial direction of the rotating base 11. When the rotor core 20 is in a straight state and the starting core unit 21a is inserted into the starting core slot 14a, the rolling assembly can rotate around the axis of the rotating base 11 to insert the remaining core units 21 into the remaining core slots 14 along the circumference of the rotating base 11, so that the rotor core 20 changes from a straight state to a circular state.

[0098] The rotor core rounding device provided in this embodiment of the invention limits the insertion of the initial core unit 21a in the starting core slot 14a along the circumferential and radial directions of the rotating base 11. This ensures that the initial core unit 21a will not wobble during the rounding process of the rotor core 20 after being inserted into the starting core slot 14a, which helps to ensure the rounding effect. Then, the rolling assembly is controlled to rotate around the axis of the rotating base 11. During the rotation of the rolling assembly around the axis of the rotating base 11, it can roll the rotor core 20, so that the remaining core units 21 will be inserted sequentially along the circumference of the rotating base 11. The remaining iron core slots 14 allow the rotor iron core 20 to switch from a flat state to a circular state. After the iron core unit 21 is inserted into the corresponding iron core slot 14, the iron core slot 14 can limit the iron core unit 21 inserted into the iron core unit 21 along the circumference of the rotating base 11, so that the iron core unit 21 cannot detach from the iron core slot 14 along the radial direction of the rotating base 11. This keeps the circular rotor iron core 20 stable, thus achieving the ability to hold the circular rotor iron core 20 without the need for clamps. This simplifies the process steps of circularizing the rotor iron core 20, thereby improving the circularization efficiency of the rotor iron core 20 and reducing production costs.

[0099] An embodiment of the present invention also provides a method for forming a rotor core into a circle, used to switch the rotor core 20 from a straight state to a circular state using the aforementioned rotor core forming device. This rotor core forming method includes the following steps:

[0100] S10. When the rotor core 20 is in a straight state, insert the starting core unit 21a into the starting core slot 14a along the axial direction of the rotating base 11.

[0101] S20. Control the rolling assembly to rotate around the axis of the rotating base 11, so that the remaining iron core units 21 are sequentially inserted into the remaining iron core slots 14 along the circumference of the rotating base 11, so that the rotor iron core 20 changes from a flat state to a circular state.

[0102] The rotor core rounding method provided in this embodiment of the invention involves inserting the initial core unit 21a into the initial core slot 14a along the axial direction of the rotating base 11 when the rotor core 20 is in a straight state; then controlling the rolling assembly to rotate around the axis of the rotating base 11, so that the remaining core units 21 are sequentially inserted into the remaining core slots 14 along the circumference of the rotating base 11, thereby changing the rotor core 20 from a straight state to a circular state. This method has the advantages of high efficiency in rounding the rotor core 20 and low production cost.

[0103] In some embodiments, the rolling fixing member 12 is integrally formed on the rotating base 11. This arrangement helps to reduce the number of parts and improve the assembly efficiency of the rotor core rounding device. It should be noted that in other embodiments, the rolling fixing member 12 can also be welded and fixed to the rotating base 11.

[0104] In some embodiments, such as Figure 6 and Figure 7 As shown, the rolled fixing member 12 forms an outer circular surface 121 on the side wall of the rotating base 11 that is radially away from the axis of the rotating base 11. The distance between two adjacent outer circular surfaces 121 along the circumference of the rotating base 11 is L11, and the dimension of the outer circular surface 121 along the circumference of the rotating base 11 is L12. The core unit 21 has two core side walls 210 arranged opposite each other along the circumference of the rotor core 20. The rotor core 20 in a circular state satisfies the following: the maximum distance between the two core side walls 210 of the core unit 21 along the circumference of the rotor core 20 is L21, the mounting slots 213 are arranged parallel to the opposite slot side walls along the circumference of the rotor core 20 and the distance is L22; L11 > L21, L22 > L12, L11 + L12 = L21 + L22.

[0105] By limiting L11 > L21, L22 > L12, and L11 + L12 = L21 + L22, the core unit 21 can be smoothly inserted into the core slot 14 during the rotation of the rotating base 11, thus preventing interference between the core unit 21 and the rolled fixing member 12.

[0106] In some embodiments, such as Figures 5 to 12 As shown, the inner magnetic bridge 211 has a rolled-out limiting fit part 2110 protruding from one end along the circumference of the rotating base 11.

[0107] The number of the coiled fixing parts 12 is 2P, where P is the number of pole pairs of the motor; the 2P coiled fixing parts 12 are divided into a first coiled fixing part 12a and 2P-1 second coiled fixing parts 12b; along the rotation direction of the rotating base 11, the first coiled fixing part 12a and the second coiled fixing part 12b located downstream and adjacent to it form an initial iron core groove 14a.

[0108] A rolling limiting groove 13 is provided at the junction of the first rolling fixing member 12a and the rotating base 11. The opening of the rolling limiting groove 13 is connected to the starting iron core groove 14a, and the rolling limiting groove 13 is provided to pass through the first rolling fixing member 12a along the axial direction of the rotating base 11. The rolling limiting mating part 2110 can be inserted into the rolling limiting groove 13 along the axial direction of the rotating base 11 so that the inner magnetic bridge 211 is limited to the rolling limiting groove 13 along the radial direction of the rotating base 11.

[0109] For example, each core slot 14 is provided through the axial direction of the rotating base 11, and the starting core unit 21a can be inserted into the starting core slot 14a along the axial direction of the rotating base 11 through either end of the starting core slot 14a.

[0110] With this configuration, the starting core unit 21a can be aligned with the starting core groove 14a along the axial direction of the rotating base 11, and the rolling limiting fitting part 2110 can be aligned with the rolling limiting groove 13 along the axial direction of the rotating base 11. This allows the starting core unit 21a to be inserted into the starting core groove 14a along the axial direction of the rotating base 11, while the rolling limiting fitting part 2110 is inserted into the rolling limiting groove 13 along the axial direction of the rotating base 11 until the starting core unit 21a is in place. The rolling limiting fitting part 2110 is then limited in the rolling limiting groove 13 along the radial direction of the rotating base 11 to prevent the starting core unit 21a from coming out of the starting core groove 14a along the radial direction of the rotating base 11. This facilitates the subsequent rotation of the rotating base 11, where each core unit 21 is sequentially inserted into each core groove 14 along the circumference of the rotating base 11.

[0111] For example, the inner magnetic bridge 211 has a rolled-up limiting fitting part 2110 at one end along the circumference of the rotor core 20, and correspondingly, a rolled-up limiting groove 13 is provided. It should be noted that, in some other embodiments, for the rotor core 20 scheme in which both ends of the inner magnetic bridge 211 along the circumference of the rotor core 20 are protruding and each forms a rolled-up limiting fitting part 2110, a rolled-up limiting groove 13 can also be provided at the junction of the first rolled-up fixing member 12a and the rotating base 11, and a rolled-up limiting groove 13 can also be provided at the junction of the second rolled-up fixing member 12b, which cooperates with the first rolled-up fixing member 12a to form the starting core groove 14a, and the rotating base 11. This allows the two rolled-up limiting fitting parts 2110 to be inserted into the two rolled-up limiting grooves 13 one-to-one during the process of inserting the starting core unit 21a into the starting core groove 14a along the axial direction of the rotating base 11.

[0112] For example, taking the inner magnetic bridge 211 having a rolled-up limiting fitting portion 2110 at one end along the circumference of the rotor core 20 as an example, the opening direction of the rolled-up limiting groove 13 is the same as the rotation direction of the rotating base 11. It should be noted that the opening direction of the rolled-up limiting groove 13 can also be opposite to the rotation direction of the rotating base 11.

[0113] In some embodiments, along the radial direction of the core unit 21, the inner magnetic bridge 211 has a limiting profile surface 2112 on its side facing the axis of the core unit 21. The limiting profile surface 2112 is a plane perpendicular to the radial direction of the rotor core 20. The limiting profile surface 2112 can abut against the permanent magnet 30 along the radial direction of the rotor core 20.

[0114] The outer peripheral wall of the rotating base 11 between two adjacent rolling fixing parts 12 forms an inner rounded surface 111, which is a plane perpendicular to the radial direction of the rotating base 11. The inner rounded surface 111 can abut against the limiting contour surface 2112 along the radial direction of the rotating base 11. With this configuration, after the iron core unit 21 is inserted into the iron core slot 14 during the rotation of the rotating base 11, the limiting contour surface 2112 can abut against the inner rounded surface 111 along the radial direction of the rotating base 11, thereby improving the rounding accuracy of the rotor iron core 20 from a flat state to a circular state using the rotor iron core rounding device.

[0115] In some embodiments, such as Figures 8 to 11 As shown, along the radial direction of the rotating base 11, the sidewall of the rolled-up limiting groove 13 near the axis of the rotating base 11 is located on the same plane as the inner circular surface 111 that forms the starting core groove 14a. This arrangement allows all the inner circular surfaces 111 on the rotating base 11 to be evenly distributed along the circumference of the rotating base 11, reducing the structural complexity of the rotating base 11 and the processing cost of the rotating base 11; moreover, it can improve the consistency of the inner magnetic bridges 211 of each core unit 21 of the rotor core 20.

[0116] In some embodiments, such as Figures 5 to 9 As shown, the outer circular surface 121 is a plane perpendicular to the radial direction of the rotating base 11, and the outer circular surface 121 can abut against the outer magnetic bridge 212 along the radial direction of the rotating base 11. This arrangement allows the outer magnetic bridge 212 to abut against the outer circular surface 121 along the radial direction of the rotating base 11 after the iron core unit 21 is inserted into the iron core slot 14 during the rotation of the rotating base 11, thereby improving the rounding accuracy when the rotor iron core 20 is switched from a flat state to a circular state using the rotor iron core rounding device.

[0117] In some embodiments, such as Figures 8 to 11 As shown, in a plane perpendicular to the axial direction of the rotating base 11, the length of the orthographic projection of the area where the outer circular surface 121 contacts the outer magnetic bridge 212 of the rotor core 20 in its flat state is greater than 0.5 mm. This arrangement ensures that when the starting core unit 21a is inserted into the starting core slot 14a along the axial direction of the rotating base 11, and the rotating base 11 has not yet started to rotate (i.e., the rotor core 20 is still entirely in a flat state), the contact area between the outer circular surface 121 and the outer magnetic bridge 212 is sufficiently large along the circumference of the rotating base 11. This ensures that after the rotating base 11 starts to rotate, the starting core unit 21a remains stably in the starting core slot 14a, facilitating the sequential insertion of the remaining core units 21 into the remaining core slots 14. This improves the rounding accuracy when the rotor core 20 is switched from a flat state to a circular state using the rotor core rounding device.

[0118] In some embodiments, such as Figures 6 to 11 As shown, along the radial direction of the core unit 21, the inner magnetic bridge 211 has a circular profile surface 2111 on the side facing the axis of the core unit 21; the second rolled-circle fixing member 12b has a rolled-circle guide surface 12b1 on the side wall facing the same rotation direction as the rotating base 11 in the two side walls that are arranged opposite each other in the circumferential direction of the rotating base 11, and the rolled-circle guide surface 12b1 is in contact with the inner side circular surface 111; the rolled-circle guide surface 12b1 can slide with the circular profile surface 2111.

[0119] During the rotation of the rotating base 11, as the core unit 21 is inserted into the core slot 14 radially along the rotating base 11, the sliding fit between the rolling guide surface 12b1 and the rounding profile surface 2111 guides the rounding profile surface 2111 to continuously approach the inner rounding surface 111 until the inner rounding surface 111 and the limiting profile surface 2112 abut against each other radially along the rotating base 11. This improves the stability of the core unit 21 during the process of inserting the core unit 21 radially into the core slot 14 along the rotating base 11, thereby improving the rounding accuracy when the rotor core 20 is switched from a flat state to a circular state using the rotor core rounding device.

[0120] Specifically, the rolled guide surface 12b1 is an arc surface, and the axis of the rolled guide surface 12b1 is parallel to the axis of the rotating base 11 and both are located on the first plane 100; the rotor core 20 in a circular state satisfies the following: the distance between the first axis and the axis of the rotor core 20 is R1; the circular profile surface 2111 is an arc surface with the first axis as the central axis and a radius of R2; the distance between the axis of the rolled guide surface 12b1 and the axis of the rotating base 11 is equal to R1, and the radius of the rolled guide surface 12b1 is greater than or equal to R2.

[0121] During the process of inserting the core unit 21 into the core slot 14, the outer magnetic bridge 212 bends and deforms around the first axis, so that the multiple core units 21 distributed along the first direction are continuously changed to be distributed circumferentially along the rotating base 11. The circular profile surface 2111 is set as an arc surface with the first axis as the central axis and a radius of R2, and the axis and radius of the circular guide surface 12b1 are determined accordingly. The sliding fit between the circular guide surface 12b1 and the circular profile surface 2111 is realized, so that the core... During the process of inserting unit 21 into the core slot 14, the sliding fit between the rolling guide surface 12b1 and the rounding profile surface 2111 guides the rounding profile surface 2111 to continuously approach the inner rounding surface 111 until the inner rounding surface 111 and the limiting profile surface 2112 abut along the rotating base 11, thereby improving the stability of the core unit 21 during the process of inserting the core unit 21 into the core slot 14, and thus improving the rounding accuracy when the rotor core 20 is switched from a flat state to a circular state using the rotor core rounding device.

[0122] For example, the radius of the rolled guide surface 12b1 is equal to R2. Figure 6 The small circle shown by the dashed line is a circle with radius R2 centered on the first axis of one of the rolled guide surfaces 12b1. Figure 6 The large circle in the middle dashed line is a circle with radius R1 centered on the axis of the rotating base 11. It should be noted that the radius of the rolled guide surface 12b1 can also be greater than R2. In this case, there is a difference between the radius of the rolled guide surface 12b1 and R2, but the difference is relatively small. This ensures that during the process of inserting the core unit 21 radially into the core slot 14 along the rotating base 11, the rolled guide surface 12b1 can still slide and engage with the circular profile surface 2111. The difference between the radius of the rolled guide surface 12b1 and R2 can be determined through repeated experiments and will not be specifically limited here.

[0123] In some embodiments, among the two sidewalls of the rolling fastener 12 arranged opposite to each other along the circumference of the rotating base 11, the sidewall facing the opposite direction of rotation of the rotating base 11 is a first limiting sidewall 122; the first limiting sidewall 122 includes a first contact surface 1221, which can abut against the core unit 21 in the opposite direction of rotation; among the two sidewalls of the first rolling fastener 12a arranged opposite to each other along the circumference of the rotating base 11, the sidewall facing the same direction of rotation is a second limiting sidewall 12a1, which includes a second contact surface 12a11; the second contact surface 12a11 can abut against the core unit 21 in the direction of rotation of the rotating base 11.

[0124] Specifically, for ease of description, the 2P core slots 14 are divided into one initial core slot 14a and 2P-1 non-initial slots 14b. The initial core slot 14a is formed between the first limiting sidewall 122 of the first rolling fixing member 12a and the second limiting sidewall 12a1 of a second rolling fixing member 12b adjacent to the first rolling fixing member 12a. The non-initial slots 14b are formed between the rolling guide surface 12b1 and the first limiting sidewall 122 located in a different rolling fixing member 12 and adjacent to it. The 2P core units 21 are divided into one initial core unit 21a and 2P-1 non-initial core units 21b.

[0125] This configuration allows the starting core unit 21a to be inserted into the starting core slot 14a and then clamped between the opposite side walls of the starting core slot 14a along the circumference of the rotating base 11. This confines the starting core unit 21a within the starting core slot 14a along the circumference of the rotating base 11, ensuring that the starting core unit 21a remains stably within the starting core slot 14a during the process of the rotor core 20 changing from a flat state to a circular state. This improves the rounding accuracy of the rotor core 20 when changing from a flat state to a circular state using the rotor core rounding device.

[0126] For the rotor core 20 in a circular state, along the radial direction of the core unit 21, the inner magnetic bridge 211 facing the axis of the core unit 21 also has a limiting profile surface 2112 that is connected to the circular profile surface 2111; the limiting profile surface 2112 is a plane perpendicular to the radial direction of the rotor core 20, and the limiting profile surface 2112 can abut against the inner circular surface 111 of the rotor core circularization device along the radial direction of the rotor core 20.

[0127] When the non-starting core unit 21b is inserted into the non-starting slot 14b, and the limiting profile surface 2112 of the inner magnetic bridge 211 located radially inside the non-starting core unit 21b abuts against the inner rounding surface 111 along the radial direction of the rotating base 11, since the rolling guide surface 12b1 and the inner rounding surface 111 are in contact, and the limiting profile surface 2112 and the rounding profile surface 2111 are in contact, and both the inner rounding surface 111 and the limiting profile surface 2112 are planar, once the limiting profile surface 2112 abuts against the inner rounding surface 111 along the radial direction of the rotating base 11, the non-starting core unit 21b cannot continue to rotate relative to the rotating base 11, and the non-starting core unit 21b has been rolled into place. At this time, the rounding profile surface 2111, which is in contact with the limiting profile surface 2112, simultaneously... The non-starting core unit 21b abuts against the rolled guide surface 12b1 that is connected to the inner rounded surface 111. At the same time, the non-starting core unit 21b abuts against the first limiting sidewall 122 that forms the non-starting slot 14b along the circumference of the rotating base 11, thereby limiting the non-starting core unit 21b that has been placed in the non-starting slot 14b along the circumference of the rotating base 11. Meanwhile, the outer magnetic bridge 212 abuts against the outer rounded surface 121 along the radial direction of the rotating base 11. The outer magnetic bridge 212 between the non-starting core unit 21b and the core unit 21 that has been placed in the core slot 14 will not continue to bend, so that the non-starting core unit 21b is stably kept in the non-starting slot 14b, thereby improving the rounding accuracy when the rotor core 20 is switched from a straight state to a circular state using the rotor core rounding device.

[0128] In some embodiments, such as Figures 8 to 11 As shown, the first limiting sidewall 122 includes at least two first contact surfaces 1221 arranged radially at intervals along the rotating base 11. The first limiting sidewall 122 satisfies the following: two adjacent first contact surfaces 1221 are connected by a first clearance surface 1222, and the first clearance surface 1222 is recessed into the rolled-up fixing member 12 along the circumferential direction of the rotating base 11.

[0129] By setting the first clearance surface 1222, interference between the first limiting sidewall 122 and the non-starting core unit 21b can be avoided during the insertion of each core unit 21 into the core slot 14, especially during the insertion of the non-starting core unit 21b into the non-starting slot 14b. The first limiting sidewall 122 is configured to include at least two first contact surfaces 1221 arranged radially at intervals along the rotating base 11. Multiple first contact surfaces 1221 can be used to circumferentially limit the core unit 21 inserted into the core slot 14, ensuring that the core unit 21 is stably held within its designated core slot 14. This improves the rounding accuracy when the rotor core 20 is switched from a straight state to a circular state using the rotor core rounding device.

[0130] In some embodiments, such as Figure 11As shown, the first contact surface 1221 is parallel to the axial direction of the rotating base 11 and is a plane extending along the axial direction of the rotating base 11. In the plane perpendicular to the axial direction of the rotating base 11, the length of the orthographic projection of the first contact surface 1221 is L31, where L31 > 1 mm. This configuration effectively utilizes the first contact surface 1221 to circumferentially limit the core unit 21 inserted into the core slot 14, while avoiding an excessively large contact area between the first limiting sidewall 122 and the core unit 21, which would affect the insertion of the core unit 21 into the core slot 14.

[0131] In some embodiments, such as Figures 8 to 11 As shown, the second limiting sidewall 12a1 includes at least two second contact surfaces 12a11 arranged radially at intervals along the rotating base 11. The second limiting sidewall 12a1 satisfies the following: two adjacent second contact surfaces 12a11 are connected by a second clearance surface 12a12, and the second clearance surface 12a12 is recessed into the rolled-up fixing member 12 along the circumferential direction of the rotating base 11.

[0132] By setting the second clearance surface 12a12, interference between the second limiting sidewall 12a1 and the starting core unit 21a can be avoided during the process of the starting core unit 21a being inserted into the starting core slot 14a, thereby improving the smoothness of the starting core unit 21a being inserted into the starting core slot 14a along the axial direction of the rotating base 11.

[0133] The second limiting sidewall 12a1 is configured to include at least two second contact surfaces 12a11 arranged radially at intervals along the rotating base 11. The multiple second contact surfaces 12a11 can be used to circumferentially limit the starting core unit 21a inserted into the starting core slot 14a, so that the starting core unit 21a is stably kept in the starting core slot 14a, thereby improving the rounding accuracy when the rotor core 20 is switched from a flat state to a circular state using the rotor core rounding device.

[0134] In some embodiments, such as Figure 11 As shown, the second contact surface 12a11 is parallel to the axial direction of the rotating base 11 and is a plane extending along the axial direction of the rotating base 11. In the plane perpendicular to the axial direction of the rotating base 11, the length of the orthographic projection of the second contact surface 12a11 is L32, where L32 > 1 mm.

[0135] This configuration effectively utilizes the first contact surface 1221 and the second contact surface 12a11 that form the starting iron core groove 14a to circumferentially limit the starting iron core unit 21a inserted into the starting iron core groove 14a, while avoiding excessive contact area between the second limiting sidewall 12a1 and the starting iron core unit 21a, which would affect the insertion of the starting iron core unit 21a into the starting iron core groove 14a.

[0136] In some embodiments, such as Figure 11As shown, the two side walls of the first circular fixing member 12a, which are arranged opposite each other along the circumference of the rotating base 11, are connected to the outer circular surface 121 through a first chamfered surface 12a2; the side wall of the second circular fixing member 12b, which is arranged opposite each other along the circumference of the rotating base 11, is connected to the outer circular surface 121 through a second chamfered surface 123; either the first chamfered surface 12a2 or the second chamfered surface 123 satisfies the following: in a plane perpendicular to the axial direction of the rotating base 11, the length of the orthographic projection of the chamfered surface is L0, L0 > (D1 - D2) / 6, where D1 is the maximum outer diameter of the rotor core 20 and D2 is the minimum inner diameter of the rotor core 20; the included angle between the chamfered surface and the connected outer circular surface 121 is α, α > 270 / P.

[0137] By limiting α and L0, L22 > L12, which prevents interference between the side of the core wall 210 away from the axis of the rotor core 20 and the first limiting side wall 122 and the second limiting side wall 12a1 during the process of inserting the core unit 21 into the core slot 14, thereby improving the smoothness of inserting the core unit 21 into the core slot 14.

[0138] In some embodiments, such as Figure 13 and Figure 14 As shown, the rotor core forming device further includes a guide platform 15 and a drive assembly. The guide platform 15 is located at one end of the rolling assembly along a first direction. The guide platform 15 is used to keep the multiple core units 21 not inserted into the core slots 14 in a straight state, and can guide the movement of the straight portion of the rotor core 20 along the first direction; the first direction is perpendicular to the axial direction of the rotating base 11. The output end of the drive assembly is connected to the rotating base 11, and the drive assembly is used to drive the rolling assembly to rotate around the axis of the rotating base 11, so as to switch the rotor core 20 from a straight state to a circular state.

[0139] Align the starting core unit 21a with the starting core groove 14a along the axial direction of the rotating base 11, and align the rolling limiting fitting part 2110 with the rolling limiting groove 13 along the axial direction of the rotating base 11; then push the rotor core 20 so that the starting core unit 21a is continuously inserted into the starting core groove 14a along the axial direction of the rotating base 11, and the rolling limiting fitting part 2110 is continuously inserted into the rolling limiting groove 13 along the axial direction of the rotating base 11, until the starting core unit 21a and the rolling limiting fitting part 2110 are both inserted into place. Then, the drive assembly is controlled to drive the rolling assembly to rotate around the axis of the rotating base 11. The non-starting core units 21b of the flat part of the rotor core 20 sequentially enter the non-starting slots 14b. During this process, the guide platform 15 keeps the multiple core units 21 that are not inserted into the core slots 14 flat and guides the movement of the flat part of the rotor core 20 toward the rolling assembly in the first direction, so as to improve the rounding accuracy when the rotor core 20 is switched from a flat state to a circular state by the rotor core rounding device.

[0140] Specifically, the guide platform 15 is provided with a guide channel 151 extending along a first direction, and the guide channel 151 is provided through at one end in the first direction to form a core outlet 1511; the guide channel 151 has two limiting groove walls 1512 arranged opposite to each other along a second direction, and the part of the rotor core 20 in a straight state can be limited between the two limiting groove walls 1512 along the second direction, and can move within the guide channel 151 along the first direction; the axial direction of the rotating base 11 and the first and second directions are perpendicular to each other. The rolling assembly is located outside the end of the guide channel 151 where the core outlet 1511 is located along the first direction, and is arranged opposite to the core outlet 1511 along the first direction.

[0141] In the rotor core rounding method provided in this embodiment of the invention, step S10 further includes the following step:

[0142] When the starting core unit 21a is inserted into the starting core groove 14a along the axial direction of the rotating base 11, the other core units 21 are placed in the guide channel 151 and limited between the two limiting groove walls 1512 of the guide channel 151 along the second direction, and the rolling limiting mating part 2110 is inserted into the rolling limiting groove 13 along the axial direction of the rotating base 11.

[0143] More specifically, the guide channel 151 is provided to form a loading port through the guide platform 15 on one side of the rotating base 11 along the axial direction. The rotor core 20, which is in a flat state, is placed on the side of the loading port of the guide platform 15 along the axial direction of the rotating base 11. The starting core unit 21a is aligned with the starting core groove 14a along the axial direction of the rotating base 11. The rolling and limiting mating part 2110 is aligned with the rolling and limiting groove 13 along the axial direction of the rotating base 11. The non-starting core unit 21b adjacent to the starting core unit 21a is aligned with the non-starting groove 14b adjacent to the starting core groove 14a along the axial direction of the rotating base 11.

[0144] Subsequently, the rotor core 20, which is in a straight state, is pushed along the axial direction of the rotating base 11, so that the starting core unit 21a is continuously inserted into the starting core slot 14a along the axial direction of the rotating base 11, and the rolling limiting mating part 2110 is continuously inserted into the rolling limiting slot 13 along the axial direction of the rotating base 11. At the same time, the non-starting core unit 21b adjacent to the starting core unit 21a is continuously inserted into the non-starting slot 14b adjacent to the starting core slot 14a along the axial direction of the rotating base 11. Other non-starting core units 21b are continuously inserted into the guide channel 151 through the feeding port along the axial direction of the rotating base 11 until all core units 21 are inserted into place.

[0145] Then, the drive assembly is controlled to drive the rolling assembly to rotate around the axis of the rotating base 11. The non-starting core units 21b of the rotor core 20 in the flat state pass through the core outlet 1511 and exit the guide channel 151 in sequence, and enter the non-starting slots 14b. During this process, the two limiting slot walls 1512 of the guide channel 151 keep the part of the rotor core 20 still in the guide channel 151 in a flat state, and guide the movement of the part of the rotor core 20 in the flat state towards the rolling assembly in the first direction, so as to improve the rounding accuracy when the rotor core 20 is switched from a flat state to a circular state by the rotor core rounding device.

[0146] In other embodiments, other structures may be used to keep the multiple core units 21 not inserted into the core slot 14 in a straight state and to guide the movement of the portion of the rotor core 20 in a straight state along a first direction. For example, two guide plates are set, which are spaced apart along the axial direction of the rotor core 20, forming a receiving space between the two guide plates. One end of the receiving space is connected to form the core outlet 1511. Guide grooves extending along the first direction are set on the opposite sides of the two guide plates along the axial direction of the rotor core 20. All guide grooves are connected at the same end along the first direction. Since each core unit 21 of the rotor core 20 has more than one magnetic isolation groove, two positioning rods can be provided for each core unit 21. Two guide grooves are set on each guide plate. The two positioning rods are inserted into different magnetic isolation grooves along the axial direction of the rotor core 20, and the two ends of each positioning rod are inserted into the guide grooves on the two guide plates respectively. The positioning rods slide in cooperation with the opposite side walls of the guide grooves along the second direction and the bottom wall of the guide grooves along the first direction. The first direction, the second direction and the axial direction of the rotating base 11 are perpendicular to each other. By utilizing the sliding engagement of the positioning rod along the first direction with the opposite side walls of the guide groove along the second direction and the bottom wall of the guide groove, and by inserting a positioning rod in each of the different magnetic isolation grooves on each core unit 21, the multiple core units 21 not inserted into the core groove 14 are kept in a straight state. The sliding engagement between the positioning rod and the guide groove along the first direction guides the movement of the part of the rotor core 20 that is kept in a straight state along the first direction.

[0147] In this embodiment of the invention, since the core unit 21 has a fan-shaped structure and each core unit 21 has its own axis, the axes of all core units 21 in the circular rotor core 20 are completely coincident, which means that the axes of the rotor core 20 are all coincident. The process of switching the rotor core 20 from a straight state to a circular state can be described as converging multiple parallel and non-coincident axes of multiple core units 21 into a completely coincident state. It should be noted that, considering the issue of circularity accuracy, the coincidence of the axes of the various core units 21 in the so-called circular rotor core 20 is not necessarily 100% coincident; errors are allowed. This error may be that the axes are parallel but have a slight gap, or it may be a slight skew. Considering the accuracy issue, in the straight rotor core 20, the axes of multiple core units 21 are parallel to each other, but not necessarily 100% parallel; slight skew errors are allowed.

[0148] In the specific implementation of the above embodiments, the technical features can be combined in any non-contradictory way. For the sake of brevity, not all possible combinations of the above technical features are described. However, as long as the combination of these technical features is not contradictory, it should be considered to be within the scope of this specification.

[0149] The specific embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A rotor core forming device, characterized in that, The rotor core (20) is a chain-type core, which includes multiple core units (21) connected in sequence. The rotor core (20) has a flat state and a circular state. When the rotor core (20) is in a flat state, the multiple core units (21) are distributed in a straight line along a first direction. The core unit (21) at one end of the rotor core (20) in the first direction is the starting core unit (21a). When the rotor core (20) is in a circular state, a mounting groove (213) for mounting permanent magnets (30) is formed between two adjacent core units (21). The rotor core forming device includes a rolling assembly, which includes a rotating base (11) capable of rotating around its own axis and a plurality of rolling fixing members (12) evenly spaced around the outer periphery of the rotating base (11) along the circumference of the rotating base (11). A core slot (14) for inserting the core unit (21) is formed between two adjacent rolling fixing members (12). The core slot (14) is provided in a one-to-one correspondence with the core unit (21), and the core slot (14) can limit the core unit (21) inserted into the core slot (14) along the circumference of the rotating base (11). One of the core slots (14) is a starting core slot (14a), which is configured to limit the starting core unit (21a) inserted therein at least along the circumferential and radial directions of the rotating base (11); When the rotor core (20) is in the flat state and the starting core unit (21a) is inserted into the starting core slot (14a), the rolling assembly can rotate around the axis of the rotating base (11) to insert the remaining core units (21) into the remaining core slots (14) in sequence along the circumference of the rotating base (11), so that the rotor core (20) changes from the flat state to the circular state.

2. The rotor core forming device according to claim 1, characterized in that, The rolled fixing member (12) forms an outer circular surface (121) on the side wall of the rotating base (11) that is radially away from the axis of the rotating base (11). The distance between two adjacent outer circular surfaces (121) along the circumference of the rotating base (11) is L11, and the dimension of the outer circular surface (121) along the circumference of the rotating base (11) is L12. The core unit (21) has two core sidewalls (210) arranged opposite each other along the circumference of the rotor core (20). The rotor core (20) in the circular state satisfies the following: the maximum distance between the two core sidewalls (210) of the core unit (21) along the circumference of the rotor core (20) is L21, and the mounting slots (213) are arranged parallel to each other along the circumference of the rotor core (20) with a distance of L22. L11>L21, L22>L12, L11+L12=L21+L22.

3. The rotor core forming device according to claim 2, characterized in that, The starting core unit (21a) is provided with an inner magnetic bridge (211) at one end near the axis of the rotor core (20), and the inner magnetic bridge (211) is provided with a rolled-out limiting fit part (2110) protruding from one end along the circumference of the rotating base (11). The number of the coiled fixing members (12) is 2P, where P is the number of pole pairs of the motor; the 2P coiled fixing members (12) are divided into a first coiled fixing member (12a) and 2P-1 second coiled fixing members (12b); along the rotation direction of the rotating base (11), the first coiled fixing member (12a) and the second coiled fixing member (12b) located downstream and adjacent to it form the starting iron core groove (14a). A rolling limiting groove (13) is provided at the junction of the first rolling fixing member (12a) and the rotating base (11). The opening of the rolling limiting groove (13) is connected to the starting iron core groove (14a), and the rolling limiting groove (13) is provided to pass through the first rolling fixing member (12a) along the axial direction of the rotating base (11). The roll-up limiting fitting part (2110) can be inserted into the roll-up limiting groove (13) along the axial direction of the rotating base (11) so that the inner magnetic bridge (211) can be limited in the roll-up limiting groove (13) along the radial direction of the rotating base (11).

4. The rotor core forming device according to claim 3, characterized in that, The outer peripheral wall of the rotating base (11) between two adjacent rolled fixing members (12) forms an inner side circular surface (111), which is a plane perpendicular to the radial direction of the rotating base (11); the inner side circular surface (111) can abut against the inner magnetic bridge (211) of the iron core unit (21) along the radial direction of the rotating base (11).

5. The rotor core forming device according to claim 4, characterized in that, Along the radial direction of the rotating base (11), the groove sidewall of the rolled limiting groove (13) near the axis of the rotating base (11) is located on the same plane as the inner circular surface (111) that forms the starting iron core groove (14a).

6. The rotor core forming device according to claim 4, characterized in that, The outer circular surface (121) is a plane perpendicular to the radial direction of the rotating base (11), and the outer circular surface (121) can abut against the outer magnetic bridge (212) of the rotor core (20) along the radial direction of the rotating base (11).

7. The rotor core forming device according to claim 6, characterized in that, Along the radial direction of the core unit (21), the inner magnetic bridge (211) has a circular profile surface (2111) on the side facing the axis of the core unit (21). The second rolled fixing member (12b) has a rolled guide surface (12b1) on one of the two side walls that are arranged opposite each other in the circumferential direction of the rotating base (11). The rolled guide surface (12b1) is in contact with the inner rounded surface (111). The rolled guide surface (12b1) can slide with the rounded contour surface (2111).

8. The rotor core forming device according to claim 7, characterized in that, The rolled guide surface (12b1) is an arc surface, and the axis of the rolled guide surface (12b1) is parallel to the axis of the rotating base (11) and both are located on the first plane (100). The rotor core (20) in a circular state satisfies the following: the inner side of the outer magnetic bridge (212) is recessed with an inner stress relief groove (2121), the inner stress relief groove (2121) is symmetrically arranged about a second plane (200) extending radially along the rotor core (20) and about the axis of the rotor core (20), the outer magnetic bridge (212) is symmetrically arranged about the second plane (200); the inner wall of the inner stress relief groove (2121) intersects the second plane (200) at a first axis, the distance between the first axis and the axis of the rotor core (20) is R1; the circular profile surface (2111) is an arc surface with the first axis as the central axis and a radius of R2; The distance between the axis of the rolled guide surface (12b1) and the axis of the rotating base (11) is equal to R1, and the radius of the rolled guide surface (12b1) is greater than or equal to R2.

9. The rotor core forming device according to claim 6, characterized in that, Of the two sidewalls of the rolled fixing member (12) arranged opposite to each other along the circumference of the rotating base (11), the sidewall facing the opposite direction of rotation of the rotating base (11) is the first limiting sidewall (122); the first limiting sidewall (122) includes a first contact surface (1221), which can abut against the core unit (21) in the opposite direction of the rotation. Of the two sidewalls of the first rolled fixing member (12a) arranged opposite each other along the circumference of the rotating base (11), the sidewall facing the same direction of rotation is the second limiting sidewall (12a1). The second limiting sidewall (12a1) includes a second contact surface (12a11). The second contact surface (12a11) can abut against the core unit (21) along the rotation direction of the rotating base (11).

10. The rotor core forming device according to claim 9, characterized in that, The first limiting sidewall (122) includes at least two first contact surfaces (1221) arranged radially at intervals along the rotating base (11). The first limiting sidewall (122) satisfies the following: two adjacent first contact surfaces (1221) are connected by a first clearance surface (1222), and the first clearance surface (1222) is recessed into the rolling fixing member (12) along the circumferential direction of the rotating base (11). And / or, the second limiting sidewall (12a1) includes at least two second contact surfaces (12a11) arranged radially spaced along the rotating base (11), the second limiting sidewall (12a1) satisfying that: two adjacent second contact surfaces (12a11) are connected by a second clearance surface (12a12), the second clearance surface (12a12) being recessed into the rolling fixing member (12) along the circumferential direction of the rotating base (11).

11. The rotor core forming device according to claim 9, characterized in that, The first rolled-circle fixing member (12a) has two side walls that are arranged opposite each other along the circumference of the rotating base (11) and are connected to the outer rounded surface (121) through a first chamfered surface (12a2); The second rolled-circle fixing member (12b) is arranged on two side walls opposite to each other along the circumference of the rotating base (11), and the side wall facing the opposite direction of the rotation is connected to the outer rounded surface (121) through the second chamfered surface (123); Either the first chamfered surface (12a2) and the second chamfered surface (123) satisfies the following: in a plane perpendicular to the axial direction of the rotating base (11), the length of the orthographic projection of the chamfered surface is L0, L0 > (D1 - D2) / 6, where D1 is the maximum outer diameter of the rotor core (20) and D2 is the minimum inner diameter of the rotor core (20); the included angle between the chamfered surface and the connected outer circular surface (121) is α, α > 270 / P.

12. The rotor core forming device according to claim 9, characterized in that, The rotor core rounding device also includes: A guide platform (15) is located at one end of the rolling assembly along the first direction. The guide platform (15) is used to keep the plurality of core units (21) not inserted into the core slot (14) in a straight state and to guide the movement of the portion of the rotor core (20) in the straight state along the first direction; the first direction is perpendicular to the axial direction of the rotating base (11). The drive assembly is connected to the rotating base (11) at its output end. The drive assembly is used to drive the rolling assembly to rotate around the axis of the rotating base (11) so as to switch the rotor core (20) from the straight state to the circular state.

13. The rotor core forming device according to claim 12, characterized in that, The guide platform (15) is provided with a guide channel (151) extending along a first direction, and the guide channel (151) is provided to form an iron core outlet (1511) at one end of the first direction. The guide channel (151) has two limiting groove walls (1512) arranged opposite to each other along the second direction. The part of the rotor core (20) in the straight state can be limited between the two limiting groove walls (1512) along the second direction, and can move in the guide channel (151) along the first direction. The axial direction, the first direction and the second direction of the rotating base (11) are perpendicular to each other. The rolling assembly is located outside the guide channel (151) at one end of the core outlet (1511) along the first direction, and is opposite to the core outlet (1511) along the first direction.

14. A rotor core, characterized in that, The rotor core (20) is switched from a straight state to a circular state using the rotor core forming device according to any one of claims 1 to 13; The rotor core (20) includes a plurality of core units (21) arranged in sequence. The rotor core (20) in the circular state satisfies the following: two adjacent core units (21) are spaced apart, and any other two adjacent rotor cores (20) are connected by an external magnetic bridge (212). The external magnetic bridge (212) is located at one end of the core unit (21) along the radial direction of the rotor core (20) away from the axis of the rotor core (20) to form a chain core. The outer magnetic bridge (212) can be bent and deformed so that the rotor core (20) can switch from a straight state to a circular state; when the rotor core (20) is in a straight state, multiple core units (21) are arranged in a straight line along the first direction; when the rotor core (20) is in a circular state, a mounting groove (213) for mounting permanent magnets (30) is formed between two adjacent core units (21). Along the radial direction of the rotor core (20), an inner magnetic bridge (211) is provided at one end of the core unit (21) near the axis of the rotor core (20); along the radial direction of the core unit (21), the inner magnetic bridge (211) has a circular profile surface (2111) on the side facing the axis of the core unit (21). The inner side of the outer magnetic bridge (212) is recessed and provided with an inner stress relief groove (2121). The inner stress relief groove (2121) is symmetrically arranged with respect to the second plane (200) about the axis of the rotor core (20). The outer magnetic bridge (212) is symmetrically arranged with respect to the second plane (200). The inner wall of the inner stress relief groove (2121) intersects the second plane (200) at a first axis, which is parallel to the axis of the rotor core (20). The circular contour surface (2111) is an arc surface with the first axis as the central axis.

15. The rotor core according to claim 14, characterized in that, The outer magnetic bridge (212) has an external stress relief groove (2122) recessed on its outer side. The external stress relief groove (2122) is symmetrically arranged about the second plane (200). The inner wall of the groove of the external magnetic bridge (212) intersects with the second plane (200).

16. The rotor core according to claim 14, characterized in that, Along the radial direction of the core unit (21), the inner magnetic bridge (211) also has a limiting profile surface (2112) that is connected to the circular profile surface (2111) on the side facing the axis of the core unit (21). The limiting profile surface (2112) is a plane perpendicular to the radial direction of the rotor core (20). The limiting profile surface (2112) can abut against the inner side of the circular surface (111) of the rotor core forming device along the radial direction of the rotor core (20).

17. A method for forming a circular rotor core, characterized in that, The rotor core (20) of any one of claims 14 to 16 is switched from a flat state to a circular state using the rotor core forming device according to any one of claims 1 to 13; the rotor core (20) forming method includes the following steps: When the rotor core (20) is in a straight state, the starting core unit (21a) is inserted into the starting core slot (14a) along the axial direction of the rotating base (11); Control the rolling assembly to rotate around the axis of the rotating base (11), so that the remaining core units (21) are sequentially inserted into the remaining core slots (14) along the circumference of the rotating base (11), so that the rotor core (20) switches from the straight state to the circular state.

18. The method for forming a round rotor core according to claim 17, characterized in that, The rotor core forming device includes a guide platform (15), and the guide platform (15) is provided with a guide channel (151). When the starting core unit (21a) is inserted into the starting core slot (14a) along the axial direction of the rotating base (11), it also Includes the following steps: All other core units (21) are placed in the guide channel (151) and limited in the second direction between the two limiting groove walls (1512) of the guide channel (151), and the rolling limiting fitting part (2110) on the starting core unit (21a) is inserted into the rolling limiting groove (13) on the rolling assembly along the axial direction of the rotating base (11).

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