CN219477699U - Rotor core and motor rotor comprising same - Google Patents

Abstract

The utility model discloses a rotor core and a motor rotor comprising the same, which are provided with an axial through shaft hole, and comprise a first end punching sheet and a second end punching sheet which are positioned at two axial ends, a plurality of middle cores positioned between the first end punching sheet and the second end punching sheet, and a plurality of first middle punching sheets alternately stacked with the middle cores. The first end punching sheet and the second end punching sheet are formed into a whole punching sheet by the magnetic pole, a first inner magnetic bridge positioned at the inner edge of the magnetic pole and a first outer magnetic bridge positioned at the outer edge of the magnetic pole, and the first middle punching sheet is formed into a whole punching sheet by the magnetic pole and a second inner magnetic bridge positioned at the inner edge of the magnetic pole. And the second end punching sheet is abutted with the end face of the permanent magnet of the motor rotor. The utility model solves the problem of insufficient strength in the traditional structure while ensuring the performance of the whole machine, improves the structural stability of the structure, effectively solves the abnormal problem of falling off of the permanent magnet after the permanent magnet is inserted by utilizing the end positioning of the second end punching sheet, and simultaneously facilitates the procedure operation.

Description

Rotor core and motor rotor comprising same

Technical Field

The utility model relates to the technical field of motor design, in particular to a rotor core and a motor rotor comprising the same.

Background

The permanent magnet brushless direct current motor has the advantages of high efficiency, energy saving and the like, is widely applied, replaces the traditional alternating current induction motor to be used in the field of air conditioning, and is a necessary trend of energy saving development in recent years.

The permanent magnet brushless direct current motor mainly comprises a stator assembly, a rotor assembly, an end cover and other parts, wherein the rotor assembly is arranged in the stator assembly, the rotor assembly is mainly formed by injection molding of a rotor core, a rotor shaft, a plurality of permanent magnets and PBT injection molding materials, the rotor core in the CN211530874U patent is formed by stacking a plurality of partition layer punching sheets and a plurality of integral connection layer punching sheets, the integral layer punching sheets are provided with shaft holes and permanent magnet mounting holes, and the integral layer connected punching sheets and fault punching sheets are overlapped along the axial direction; however, the outer parts of the rotor core punching sheets are not connected, so that the strength of the whole structure of the iron core is poor, the phenomena of deformation and the like after the punching sheets are extruded easily occur in the process of inserting magnetic steel, and meanwhile, the rotor punching sheets in faults are insufficient in whole strength, easy to deviate and the like after lamination due to small contact area of tooth parts of the iron core.

In addition, for the permanent magnet motor, a permanent magnet is utilized to provide a magnetic field, and the permanent magnet rotor can be generally divided into a surface-mounted permanent magnet rotor and an internal permanent magnet rotor according to different mounting modes of the permanent magnet and the rotor, and compared with the surface-mounted rotor, the internal permanent magnet rotor has the obvious advantages of reducing demagnetization of armature reaction and centrifugal force during high-speed operation, but the existing internal rotor is easy to cause the problems that the permanent magnet is difficult to position during the mounting of the permanent magnet, easy to fall off after insertion, the permanent magnet generates offset during the injection molding of PBT material, and the like, so that the overall performance of the rotor is influenced.

Disclosure of Invention

In order to solve the technical problems that in the prior art, the rotor core is poor in overall structural strength and easy to squeeze and deform due to the design of faults, the utility model provides a rotor core and a motor rotor comprising the rotor core.

The utility model provides a rotor iron core, which is provided with an axial through shaft hole, and comprises a first end punching sheet, a second end punching sheet, a plurality of middle iron cores and a plurality of first middle punching sheets, wherein the first end punching sheet and the second end punching sheet are positioned at two axial ends; the intermediate core is formed by stacking a plurality of second intermediate laminations.

The first end punching sheet, the second end punching sheet, the first middle punching sheet and the second middle punching sheet all comprise a plurality of magnetic poles which are arranged in a circumferential array, a permanent magnet positioning groove is formed between two adjacent magnetic poles in the circumference, the first end punching sheet and the second end punching sheet are formed into a whole punching sheet by the magnetic poles and a first inner magnetic bridge positioned at the inner edge of the magnetic poles and a first outer magnetic bridge positioned at the outer edge of the magnetic poles, the first middle punching sheet is formed into a whole punching sheet by the magnetic poles and a second inner magnetic bridge positioned at the inner edge of the magnetic poles, and the magnetic poles in the second middle punching sheet are not connected with each other.

And the length L of the permanent magnet positioning groove of the second end punching sheet is smaller than the width L1 of the permanent magnet, so that the second end punching sheet is abutted with the end face of the permanent magnet of the motor rotor.

Further, the first inner magnetic bridge width of the second end punch is greater than the first inner magnetic bridge width of the first end punch.

Further, the outer circumferential surfaces of the first inner magnetic bridge and the second inner magnetic bridge are polygonal surfaces, so that the cross section of the permanent magnet positioning groove is rectangular.

Further, L1-l=0.5 mm to 1mm.

Further, the inner circumferential surface of the magnetic pole in the second middle punching sheet is provided with an arc positioning tooth, the inner circumferential surface of the arc positioning tooth is an arc surface, and the arc length of the arc positioning tooth is gradually increased from one end close to the magnetic pole to one end far away from the magnetic pole.

Further, the circular arc positioning teeth are symmetrically arranged relative to the symmetry center of the magnetic pole.

The utility model provides a motor rotor which comprises the rotor core, a rotor shaft penetrating through the shaft hole and a permanent magnet inserted into the permanent magnet positioning groove.

Further, the contact surface of the permanent magnet and the permanent magnet positioning groove is provided with a positioning groove and a positioning lug which are matched with each other.

Further, the positioning convex blocks are protruded from one side of the permanent magnet positioning grooves to the direction of the permanent magnet, and the positioning grooves penetrate through two ends of the permanent magnet along the length direction of the permanent magnet.

Further, the cross section of the positioning lug is arc-shaped, and the diameter of the positioning lug is 1 mm-1.5 mm.

The beneficial effects of the utility model are as follows:

(1) The rotor core and the motor rotor comprising the same fully utilize the related combination structure of the inner magnetic bridge and the outer magnetic bridge in the punching sheets at the two ends, and the first middle punching sheet with the inner magnetic bridge is arranged between the middle iron cores of the faults, so that the problem of insufficient strength in the traditional structure is solved while the performance of the whole machine is ensured, the structural stability is improved, and meanwhile, the abnormal problem of falling off after the permanent magnet is inserted is effectively solved by utilizing the end positioning of the punching sheets at the second end, and meanwhile, the process operation is convenient.

(2) According to the rotor core and the motor rotor comprising the rotor core, the fan-shaped arc positioning teeth are designed on the inner peripheral surface of the magnetic pole in the second middle punching sheet, the arc positioning teeth of the magnetic pole after single lamination increase the contact area, the friction force of the magnetic pole and the bonding strength with PBT are increased after the PBT material is injection molded, and the overall strength of the magnetic pole is greatly improved.

(3) According to the rotor core and the motor rotor comprising the same, the permanent magnets and the permanent magnet positioning grooves are positioned through the concave-convex grooves, so that displacement caused by impact of PBT material on the permanent magnets in the injection molding process can be prevented, the magnetic performance loss caused by permanent magnet deflection is reduced, and the performance of the whole machine is improved.

Drawings

The utility model will be further described with reference to the drawings and examples.

Fig. 1 is an exploded view of a rotor core according to the present utility model;

FIG. 2 is a front view of a first end punch of the present utility model;

FIG. 3 is a front view of a first intermediate die of the present utility model;

fig. 4 is a perspective view of a prior art intermediate core.

Fig. 5 is a magnetic pole perspective view of the intermediate core of the present utility model;

FIG. 6 is a front view of a second end punch of the present utility model;

fig. 7 is an axial perspective sectional view of a rotor core according to the present utility model;

FIG. 8 is a schematic illustration of the positional relationship of the second end punch and the permanent magnet;

FIG. 9 is an enlarged view of the permanent magnet detent in the present utility model;

fig. 10 is a perspective view of a specific embodiment of a motor rotor according to the present utility model.

In the figure, 1, a first end punching sheet, 2, a second end punching sheet, 3, an intermediate iron core, 301, a second intermediate punching sheet, 302, arc positioning teeth, 4, a first intermediate punching sheet, 5, magnetic poles, 6, a permanent magnet positioning groove, 7, a first inner magnetic bridge, 8, a first outer magnetic bridge, 9, a second inner magnetic bridge, 10, a rotor iron core, 11, a shaft hole, 12, a rotor shaft, 13, a permanent magnet, 14, a positioning groove, 15 and a positioning lug.

Detailed Description

Embodiments of the present utility model are described in detail below, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the drawings are illustrative only and are not to be construed as limiting the utility model.

As shown in fig. 1 to 3 and 5 to 7, the rotor core 10 has an axial hole 11 passing through in the axial direction, and includes first and second end punches 1 and 2 at both ends in the axial direction, a plurality of intermediate cores 3 between the first and second end punches 1 and 2, and a plurality of first intermediate punches 4 stacked alternately with the intermediate cores 3; the intermediate core 3 is formed by stacking a plurality of second intermediate laminations 301.

The first end punching sheet 1, the second end punching sheet 2, the first middle punching sheet 4 and the second middle punching sheet 301 all comprise a plurality of magnetic poles 5 which are arranged in a circumferential array, a permanent magnet positioning groove 6 is formed between two magnetic poles 5 which are adjacent in circumference, the first end punching sheet 1 and the second end punching sheet 2 are formed into a whole punching sheet by the magnetic poles 5 and a first inner magnetic bridge 7 positioned at the inner edge of the magnetic poles 5, a first outer magnetic bridge 8 positioned at the outer edge of the magnetic poles 5, the first middle punching sheet 4 is formed into a whole punching sheet by the magnetic poles 5 and a second inner magnetic bridge 9 positioned at the inner edge of the magnetic poles 5, and the magnetic poles 5 in the second middle punching sheet 301 are not connected with each other.

And the length L of the permanent magnet positioning groove 6 of the second end punching sheet 2 is smaller than the width L1 of the permanent magnet 13, so that the second end punching sheet 2 is abutted with the end face of the permanent magnet 13 of the motor rotor.

The utility model consists of four rotor punching sheets, two end punching sheets at two ends are both formed by a single rotor punching sheet, the problem that the magnetic pole 5 is easy to deform caused by no outer magnetic bridge is solved by utilizing the first outer magnetic bridge 8, the combination of the first outer magnetic bridge 8 and the first inner magnetic bridge 7 is fully utilized to obtain the state of the best combination of the structure and the performance, a plurality of middle second middle punching sheets 301 are laminated along the axial direction, a plurality of magnetic poles 5 of a circumferential array form a middle iron core 3, at least one layer of the middle iron core 3 is provided with a first middle punching sheet 4 formed by the single rotor punching sheet, and the second inner magnetic bridge 9 in the first middle punching sheet 4 is utilized to stabilize the whole iron core structure. Finally, by reducing the size of the permanent magnet positioning groove 6 of the second end punching sheet 2, the second end punching sheet 2 positions the permanent magnet 13, when the permanent magnet 13 is inserted into the groove from top to bottom from the permanent magnet positioning groove 6 of the first end punching sheet 1, and when the permanent magnet 13 contacts the second end punching sheet 2, the second end punching sheet 2 can position the permanent magnet 13 to prevent the permanent magnet 13 from continuously moving downwards, thereby effectively solving the problem that the permanent magnet 13 falls off after being inserted, and simultaneously facilitating the procedure operation.

Example 1

As shown in fig. 1, a rotor core 10 has an axial through shaft hole 11, the rotor core 10 has a seven-layer structure formed by four rotor punching sheets, a first end punching sheet 1 of a first layer has an integral structure, and is provided with the shaft hole 11, a permanent magnet positioning slot 6, a first inner magnetic bridge 7, a second outer magnetic bridge and ten magnetic poles 5 arranged in a circumferential array, and tooth parts of the magnetic poles 5 face the shaft hole 11 (as shown in fig. 2).

The second, fourth and sixth layers are intermediate iron cores 3 formed by superposing a plurality of second intermediate punching sheets 301, and each layer of second intermediate punching sheet 301 is provided with a shaft hole 11, a permanent magnet positioning groove 6 and ten magnetic poles 5 which are arranged in a circumferential array. The second middle punching sheet 301 is a fault punching sheet, and the disconnection is mainly used for reducing the magnetic loss of the motor rotor and improving the performance of the whole machine.

A layer of first middle punching sheet 4 is arranged between the adjacent middle iron cores 3, namely, the third and fifth layers are the first middle punching sheet 4, the first middle punching sheet 4 is of an integral structure, a shaft hole 11, a second inner magnetic bridge 9, permanent magnet positioning slots 6 and ten magnetic poles 5 (shown in fig. 3) which are arranged in a circumferential array are arranged, and the first middle punching sheet 4 is used for stabilizing the integral iron core structure.

The second end punching sheet 2 of the seventh layer has the same structure as the first layer, and the difference is that the length L of the permanent magnet positioning groove 6 of the second end punching sheet 2 is smaller than the width L1 of the permanent magnet 13 (as shown in fig. 8), the length L of the permanent magnet positioning groove 6 refers to the radial dimension of the permanent magnet positioning groove 6, and the width L1 of the permanent magnet 13 refers to the dimension parallel to the length of the permanent magnet positioning groove 6 on the permanent magnet 13. The length L of the permanent magnet positioning slot 6 can be achieved by changing the width of the first inner magnetic bridge 7 or the first outer magnetic bridge 8, in this embodiment, the width of the first inner magnetic bridge 7 of the second end punch 2 is larger than the width of the first inner magnetic bridge 7 of the first end punch 1. The width of the first inner magnetic bridge 7 refers to the dimension along the radial direction of the second end punching sheet 2, and is also the dimension parallel to the length direction of the permanent magnet positioning slot 6. Preferably, L1-l=0.5 mm to 1mm, which can achieve a positioning effect and reduce magnetic loss.

In the rotor core 10 in the prior art, the outer circles of the punching sheets of the integral structure are not connected, the integral strength of the core is insufficient, and the first end punching sheet 1 and the second end punching sheet 2 of the utility model utilize the combination of an inner magnetic bridge and an outer magnetic bridge to avoid the deformation of the magnetic pole 5, so that the state of the best combination of the structure and the performance is obtained. In the rotor in the prior art, the permanent magnet 13 is positioned in a non-planar manner, but is positioned in a matched manner with the chamfer surface of the permanent magnet 13, so that the difficulty and cost of the actual production process can be increased, the chamfer size in the production process of the permanent magnet 13 cannot be accurate, and the performance and noise are affected due to poor matching precision after the permanent magnet 13 is assembled to the rotor core 10. The second end punching sheet 2 in the utility model not only has the function of improving strength, but also has the function of positioning, and prevents the permanent magnet 13 from falling off after being inserted.

Example two

On the basis of the first embodiment, the inner peripheral surface of the magnetic pole 5 in the second intermediate punching sheet 301 is provided with the circular arc positioning teeth 302, the inner peripheral surface of the circular arc positioning teeth 302 is a circular arc surface, and the arc length of the circular arc positioning teeth 302 gradually increases from one end close to the magnetic pole 5 to one end far from the magnetic pole 5. In the rotor core 10 of the prior art, the fault punching sheet has no circular arc positioning teeth, as shown in fig. 4, the inner peripheral surface of the fault punching sheet is square, and after a plurality of punching sheets are laminated, the tooth parts of the punching sheets have small contact areas, so that the problems of weak structural strength and easy noise generation of the rotor are caused.

In this embodiment, the tooth portion of the magnetic pole 5 is provided with the arc positioning tooth 302, so as to increase the strength of the iron core, and reduce the magnetic leakage through the design of the width of the gradient from outside to inside, specifically, as shown in fig. 5, the arc length D of the arc positioning tooth 302 is required to be within 2.0-2.5mm, the diameter of the arc positioning tooth 302 is equal to that of the shaft hole 11, the contact area of the arc positioning tooth 302 of the tooth portion of the magnetic pole 5 after lamination is increased, the friction force between punching sheets is increased, meanwhile, the bonding strength with the PBT is also increased after the PBT material is injection molded, the overall strength of the intermediate iron core 3 is greatly improved, the noise is reduced, and the overall effect is shown in fig. 8. Preferably, the circular arc positioning teeth 302 are symmetrically arranged relative to the symmetry center of the magnetic pole 5, so as to ensure uniform stress.

In this embodiment, the outer circumferential surfaces of the first inner magnetic bridge 7 and the second inner magnetic bridge 9 are polygonal surfaces so that the cross section of the permanent magnet positioning groove 6 is rectangular. As shown in fig. 2, 3 and 6, the outer circles of the first inner magnetic bridge 7 and the second inner magnetic bridge 9 are polygonal structures, and the inner circles are designed to be circular structures, so that strength is increased by using the polygonal structures of the outer circles, the difficulty of high-speed stamping is reduced by using the circular inner circles, and the circular positioning teeth 302 (shown in fig. 7) of the second middle stamping 301 are matched.

Example III

As shown in fig. 10, a motor rotor includes the above-described rotor core 10, a rotor shaft 12 passing through a shaft hole 11, and permanent magnets 13 inserted into permanent magnet positioning grooves 6. The permanent magnet 13 is inserted into the permanent magnet positioning groove 6, the rotor shaft 12 is placed into the shaft hole 11 of the rotor core 10, and PBT material is uniformly injected into the rotor core 10 through an injection mold, so that the motor rotor is formed.

Example IV

The existing built-in rotor is easy to have the problem that the permanent magnets 13 are offset when the PBT material is injected during the installation of the permanent magnets 13, so that the overall performance of the rotor is affected. This problem is mainly due to the fact that the permanent magnet 13 is not positioned effectively in the permanent magnet positioning groove 6, and therefore, the present embodiment is modified based on the third embodiment in that the contact surface of the permanent magnet 13 and the permanent magnet positioning groove 6 is provided with a positioning groove 14 and a positioning protruding block 15 which are matched with each other. The positioning groove 14 and the positioning protruding block 15 can be interchanged, in this embodiment, the positioning protruding block 15 is located on the permanent magnet positioning groove 6, and protrudes from one side of the permanent magnet positioning groove 6 toward the permanent magnet 13 (as shown in fig. 9), the positioning groove 14 is located on the permanent magnet 13, and penetrates through two ends of the permanent magnet 13 along the length direction of the permanent magnet 13 (as shown in fig. 8). Preferably, the cross section of the positioning lug 15 is arc-shaped, and the arc-shaped diameter of the positioning lug 15 is 1 mm-1.5 mm. The design of the arc surface can avoid scratching the surface of the permanent magnet 13 and causing magnetic loss.

As shown in fig. 8 and 9, the permanent magnet positioning slots 6 are provided with a positioning protruding block with a diameter of 1mm, and the corresponding permanent magnet 13 is provided with a positioning slot with the same size on one side, when the permanent magnet 13 is inserted into the permanent magnet positioning slot 6 of the rotor core 10, the positioning protruding block and the positioning slot can be tightly matched, the permanent magnet 13 is positioned, the permanent magnet 13 is prevented from being deviated, meanwhile, the operation of the procedure is also convenient, in the rotor injection molding process, due to the positioning of the positioning protruding block and the positioning slot, the displacement generated by the impact of the PBT material on the permanent magnet 13 in the injection molding process can be prevented, the magnetic property loss caused by the deviation of the permanent magnet 13 is reduced, and the performance and noise of the whole machine are improved.

In the description of the present utility model, it should be understood that the terms "center," "length," "width," "inner," "outer," "axial," "radial," and the like indicate orientations or positional relationships based on the orientation or positional relationships shown in the drawings, merely to facilitate description of the present utility model and simplify the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present utility model.

Furthermore, the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. In the description of the present utility model, it should be noted that, unless explicitly stated and limited otherwise, the term "connected" should be interpreted broadly, and for example, it may be a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium. The specific meaning of the above terms in the present utility model will be understood in specific cases by those of ordinary skill in the art. Furthermore, in the description of the utility model, unless otherwise indicated, the meaning of "a number" is one or more than one.

In this specification, a schematic representation of the terms does not necessarily refer to the same embodiment. Furthermore, the particular features, structures, materials, or characteristics may be combined in any suitable manner in any one or more embodiments.

With the above-described preferred embodiments according to the present utility model as an illustration, the above-described descriptions can be used by persons skilled in the relevant art to make various changes and modifications without departing from the scope of the technical idea of the present utility model. The technical scope of the present utility model is not limited to the description, but must be determined according to the scope of claims.

Claims (10)

1. A rotor core (10) having an axial through-hole (11), characterized in that: comprises a first end punching sheet (1) and a second end punching sheet (2) which are positioned at two axial ends, a plurality of middle iron cores (3) positioned between the first end punching sheet (1) and the second end punching sheet (2) and a plurality of first middle punching sheets (4) which are alternately stacked with the middle iron cores (3); the middle iron core (3) is formed by stacking a plurality of second middle punching sheets (301);

the first end punching sheet (1), the second end punching sheet (2), the first middle punching sheet (4) and the second middle punching sheet (301) all comprise a plurality of magnetic poles (5) which are arranged in a circumferential array, a permanent magnet positioning groove (6) is formed between two adjacent magnetic poles (5) in the circumference, the first end punching sheet (1) and the second end punching sheet (2) are formed into a whole sheet by the magnetic poles (5) and a first inner magnetic bridge (7) positioned at the inner edge of the magnetic poles (5), a first outer magnetic bridge (8) positioned at the outer edge of the magnetic poles (5), the first middle punching sheet (4) is formed into a whole sheet by the magnetic poles (5) and a second inner magnetic bridge (9) positioned at the inner edge of the magnetic poles (5), and the magnetic poles (5) in the second middle punching sheet (301) are not connected with each other;

and the length L of the permanent magnet positioning groove (6) of the second end punching sheet (2) is smaller than the width L1 of the permanent magnet (13), so that the second end punching sheet (2) is abutted with the end face of the permanent magnet (13) of the motor rotor.

2. The rotor core of claim 1, wherein: the width of the first inner magnetic bridge (7) of the second end punching sheet (2) is larger than that of the first inner magnetic bridge (7) of the first end punching sheet (1).

3. The rotor core of claim 1, wherein: the outer peripheral surfaces of the first inner magnetic bridge (7) and the second inner magnetic bridge (9) are polygonal surfaces, so that the cross section of the permanent magnet positioning groove (6) is rectangular.

4. The rotor core of claim 1, wherein: L1-L=0.5 mm to 1mm.

5. The rotor core of claim 1, wherein: the inner peripheral surface of the magnetic pole (5) in the second middle punching sheet (301) is provided with an arc positioning tooth (302), the inner peripheral surface of the arc positioning tooth (302) is an arc surface, and the arc length of the arc positioning tooth (302) is gradually increased from one end close to the magnetic pole (5) to one end far away from the magnetic pole (5).

6. The rotor core as recited in claim 5, wherein: the circular arc positioning teeth (302) are symmetrically arranged relative to the symmetry center of the magnetic pole (5).

7. A motor rotor, characterized in that: a rotor core (10) comprising any one of claims 1-6, a rotor shaft (12) passing through the shaft hole (11), and permanent magnets (13) inserted into the permanent magnet positioning slots (6).

8. The motor rotor of claim 7, wherein: the contact surface of the permanent magnet (13) and the permanent magnet positioning groove (6) is provided with a positioning groove (14) and a positioning lug (15) which are matched with each other.

9. The motor rotor of claim 8, wherein: the positioning convex blocks (15) are protruded from one side of the permanent magnet positioning grooves (6) to the direction of the permanent magnet (13), and the positioning grooves (14) penetrate through two ends of the permanent magnet (13) along the length direction of the permanent magnet (13).

10. The motor rotor of claim 8, wherein: the cross section of the positioning lug (15) is arc-shaped, and the diameter of the positioning lug (15) is 1 mm-1.5 mm.