CN110365146A - Motor rotor, motor and motor rotor assembly method - Google Patents

Abstract

The present invention relates to electrical equipment technical field more particularly to the assembly method of motor rotor, motor and motor rotor, to improve the operating reliability and the torque that can bear of shaft of motor.The motor rotor includes shaft and the rotor core for being sheathed on shaft, rotor core is fixed with multiple circumferentially distributed permanent magnets, it is characterized in that, rotor core includes the mounting hole for being arranged shaft, the inner wall of mounting hole has the groove axially extended, the diameter of shaft is greater than the aperture of mounting hole, and the depth of groove is greater than the difference between the diameter of shaft and the aperture of mounting hole.

Description

Motor rotor, motor and motor rotor assembly method

technical field

The invention relates to the technical field of electric equipment, in particular to a motor rotor, a motor and an assembly method for the motor rotor.

Background technique

Due to the wide range of power that the motor can provide, it has been used in all aspects of modern social life with the development of the economy and the improvement of productivity. A motor is a device that converts electrical energy into mechanical energy. It uses the stator winding to generate a rotating magnetic field and acts on the rotor to form a magnetoelectric force rotating torque.

Usually, the above-mentioned stator winding is a energized coil, and the above-mentioned rotor includes a rotating shaft and a rotor electric core sheathed on the rotating shaft, and a plurality of permanent magnets are fixed on the rotor iron core. When the motor is working, the stator applies an electromagnetic field to the outside of the rotor. The above electromagnetic field drives the rotor core to rotate through the repulsion or attraction effect with the magnetic field generated by the permanent magnet fixed on the rotor core, thereby driving the shaft to rotate and converting electrical energy into Kinetic energy, and then output the kinetic energy to external machinery through the rotating shaft. Therefore, it is necessary to mechanically fix the rotor core and the rotating shaft, and in order to improve the reliability of the mechanical fixing between the rotating shaft and the rotor core and to increase the torque that the rotating shaft can withstand, it is necessary to increase the fixing strength between the rotating shaft and the rotor core.

Contents of the invention

The invention provides a motor rotor, a motor and an assembly method of the motor rotor, the fixing strength between the rotating shaft and the rotor iron core is improved, thereby improving the operation reliability of the motor and the torque that the rotating shaft can bear.

To this end, the embodiment of the present invention provides a motor rotor, the motor rotor includes: a rotating shaft and a rotor core sheathed on the rotating shaft, the rotor core is fixed with a plurality of permanent magnets distributed along the circumferential direction, so The rotor core includes a mounting hole where the rotating shaft is sleeved, and the inner wall of the mounting hole has a groove extending in the axial direction. Before being sleeved, the diameter of the rotating shaft is larger than the diameter of the mounting hole, and the groove The depth of the groove is larger than the difference between the diameter of the rotating shaft and the diameter of the mounting hole.

In this technical solution, the rotating shaft and the rotor core can realize interference assembly; as the interference between the rotating shaft and the mounting hole increases, the groove on the inner wall of the mounting hole can also increase the friction between the mounting hole and the rotating shaft, improving The tangential force between the mounting hole and the rotating shaft further improves the fixing strength between the rotating shaft and the rotor core, and increases the torque that can be transmitted between the mounting hole and the rotating shaft.

In a preferred technical solution, after the rotating shaft and the rotor core are sheathed, a corrugated structure protruding into the groove is formed in the area of the rotating shaft opposite to the groove.

In this embodiment, not only the interference between the rotating shaft and the mounting hole is increased, but also the convex structure on the rotating shaft and the groove can be clamped in the circumferential direction, the ability to transmit tangential force is further strengthened, and the rotating shaft is further improved. The fixed strength between the motor and the rotor core increases the torque that the shaft of the motor can withstand.

Specifically, the heat-pressing fit stress between the rotating shaft and the rotor core is smaller than the yield strength of the material of the rotating shaft and smaller than the yield strength of the rotor core material. The heat-pressing fixing fit stress will not cause damage to the material of the rotating shaft and the rotor core, thereby ensuring the fixing strength between the rotating shaft and the rotor core and effectively transmitting torque.

In one of the technical solutions, the groove includes a plurality of grooves distributed circumferentially along the inner wall of the installation hole. In this way, the fixing strength between the rotating shaft and the rotor core can be further improved.

In one of the technical solutions, the permanent magnets are arranged in such a manner that the magnetic pole directions of adjacent permanent magnets are opposite, and the number and position of the plurality of grooves are set to be opposite to a group of permanent magnets in which the magnetic pole directions are the same. The groove can be used as a mark to distinguish two sets of permanent magnets with opposite magnetic pole directions. When installing or replacing a permanent magnet, the operator can directly judge the magnetic pole direction of the permanent magnet according to the position of the groove without additional Detection work, improve work efficiency.

In a preferred technical solution, along the circumferential direction, the center of the groove and the center of the permanent magnet opposite to the groove deviate by a set angle; the motor rotor includes at least two rotor cores, from the Viewed from the shaft end of the rotating shaft, the assembly directions of two adjacent rotor cores are opposite and the grooves are connected.

In this scheme, the permanent magnets of the two rotor cores are staggered, and the space between the two adjacent permanent magnets can be supplemented with each other, so that the magnetic field of the rotor core tends to be uniform in the circumferential direction, and the uniformity of the rotation of the motor rotor can be improved. sex.

In one of the technical proposals, the rotor core further includes an anti-flux hole formed corresponding to each permanent magnet. Viewed from the shaft end of the rotating shaft, the cross-sectional shape of the anti-flux hole is an isosceles triangle, and the The vertex of the isosceles triangle points to the central position of the permanent magnet, the cross-sectional shape of the permanent magnet is a rectangle, and the groove is formed on: the extension line of the sides of the two ends of the rectangle, the side of the isosceles triangle The area enclosed by the extension lines of the two isosceles sides and the edge lines of the mounting hole. The magnetic field in this area is relatively weak, which can be regarded as the weak magnetic area of the rotor core, and the grooves are set in the weak magnetic area of the rotor core, which has little influence on the magnetic field of the rotor core, so that the rotor has good performance.

Based on the same inventive concept, the present invention also provides another motor rotor, which includes a rotating shaft and a rotor core sleeved on the rotating shaft, and the rotor core is fixed with a plurality of permanent magnets distributed along the circumferential direction , the rotor core includes a mounting hole sleeved with the rotating shaft, the inner wall of the mounting hole has a groove extending in the axial direction, the rotating shaft and the rotor core are assembled through a hot pressing process or a physical pressing process Assembled, and a corrugated structure protruding into the groove is formed in the area where the rotating shaft is opposite to the groove.

In this technical solution, not only the interference between the shaft and the mounting hole is increased, but also the convex structure on the shaft and the groove can be clamped in the circumferential direction, the ability to transmit tangential force is further strengthened, and the shaft is further improved. The fixed strength between the motor and the rotor core increases the torque that the shaft of the motor can withstand.

Specifically, the heat-pressing fit stress between the rotating shaft and the rotor core is smaller than the yield strength of the material of the rotating shaft and smaller than the yield strength of the rotor core material. The heat-pressing fixing fit stress will not cause damage to the material of the rotating shaft and the rotor core, thereby ensuring the fixing strength between the rotating shaft and the rotor core and effectively transmitting torque.

In one of the technical solutions, the groove includes a plurality of grooves distributed circumferentially along the inner wall of the installation hole. In this way, the fixing strength between the rotating shaft and the rotor core can be further improved.

In one of the technical solutions, the permanent magnets are arranged in such a manner that the magnetic pole directions of adjacent permanent magnets are opposite, and the number and position of the plurality of grooves are set to be opposite to a group of permanent magnets in which the magnetic pole directions are the same. The groove can be used as a mark to distinguish two sets of permanent magnets with opposite magnetic pole directions. When installing or replacing a permanent magnet, the operator can directly judge the magnetic pole direction of the permanent magnet according to the position of the groove without additional Detection work, improve work efficiency.

In a preferred technical solution, along the circumferential direction, the center of the groove and the center of the permanent magnet opposite to the groove deviate by a set angle; the motor rotor includes at least two rotor cores, from the Viewed from the shaft end of the rotating shaft, the assembly directions of two adjacent rotor cores are opposite and the grooves are connected.

In this scheme, the permanent magnets of the two rotor cores are staggered, and the space between the two adjacent permanent magnets can be supplemented with each other, so that the magnetic field of the rotor core tends to be uniform in the circumferential direction, and the uniformity of the rotation of the motor rotor can be improved. , thereby improving the uniformity of the rotation speed of the motor rotor.

In one of the technical proposals, the rotor core further includes an anti-flux hole formed corresponding to each permanent magnet. Viewed from the shaft end of the rotating shaft, the cross-sectional shape of the anti-flux hole is an isosceles triangle, and the The vertex of the isosceles triangle points to the central position of the permanent magnet, the cross-sectional shape of the permanent magnet is a rectangle, and the groove is formed on: the extension line of the sides of the two ends of the rectangle, the side of the isosceles triangle The area enclosed by the extension lines of the two isosceles sides and the edge lines of the mounting hole. The magnetic field in this area is relatively weak, which can be regarded as the weak magnetic area of the rotor core, and the grooves are set in the weak magnetic area of the rotor core, which has little influence on the magnetic field of the rotor core, so that the rotor has good performance.

The present invention also provides a motor, which includes the motor rotor in any one of the above technical solutions. The electric motor has high operating reliability, and the output torque is larger.

Based on the same inventive concept, the present invention also provides an assembly method of a motor rotor, which is applied to the motor rotor in the above technical solution, and specifically includes the following steps:

In the heating step of heating the rotor core, the heating temperature and duration are such that the diameter of the installation hole on the rotor core where the rotating shaft is sleeved is larger than the diameter of the rotating shaft;

a step of sheathing the heated rotor core on the rotating shaft to form the motor rotor;

In the cooling step of cooling the rotor of the electric motor, the area of the rotating shaft opposite to the groove extending in the axial direction on the inner wall of the mounting hole forms a corrugated structure protruding into the groove.

In this technical solution, the rotor core and the rotating shaft are installed through a hot pressing process to realize the interference assembly of the two, and the area where the rotating shaft is opposite to the groove forms a corrugated structure. The corrugated structure on the rotating shaft and the groove can be clamped in the circumferential direction, the ability to transmit tangential force is further strengthened, the fixing strength between the rotating shaft and the rotor core is further improved, and the bearing capacity of the rotating shaft of the motor can be improved. torque.

In a specific technical solution, the heating step specifically includes: heating at least two rotor cores, the rotor cores are fixed with a plurality of permanent magnets distributed along the circumferential direction, and along the circumferential direction of the rotor cores, The center of the groove and the center of the permanent magnet opposite to the groove set an angle of deviation;

The sheathing step specifically includes: respectively sheathing the heated rotor cores on the rotating shaft, wherein two adjacent rotor cores are installed in opposite directions, and the grooves of the at least two rotor cores connected.

In this technical scheme, the motor rotor is formed after installation, and the permanent magnets of the two rotor cores are staggered, so that the space between the two adjacent permanent magnets can be supplemented with each other, so that the magnetic field of the rotor core tends to be uniform in the circumferential direction. Improve the uniformity of the rotation of the motor rotor, thereby improving the uniformity of the rotation speed of the motor rotor.

Based on the same inventive concept, the present invention also provides an assembly method of a motor rotor, which is applied to the motor rotor in the above technical solution, and specifically includes the following steps:

The pressing step of pressing the rotating shaft into the rotor core, before pressing in, the diameter of the rotating shaft is larger than the diameter of the installation hole, and the depth of the groove is larger than the diameter of the rotating shaft and the mounting hole. The difference between the apertures of the holes, after being pressed in, the area of the rotating shaft opposite to the groove located on the inner wall of the installation hole and extending in the axial direction forms a corrugated structure protruding into the groove.

In this technical solution, the area where the rotating shaft is opposite to the groove can also form a corrugated structure. The corrugated structure on the rotating shaft and the groove can be clamped in the circumferential direction, the ability to transmit tangential force is further strengthened, the fixing strength between the rotating shaft and the rotor core is further improved, and the bearing capacity of the rotating shaft of the motor can be improved. torque.

Description of drawings

Fig. 1 shows the structural representation of the first embodiment of the motor rotor of the present invention;

Fig. 2 shows the schematic cross-sectional structure diagram of the first embodiment of the motor rotor of the present invention;

Fig. 3 shows the schematic cross-sectional structure diagram of the second embodiment of the motor rotor of the present invention;

Fig. 4 shows a partial enlarged view of place A in Fig. 3;

Fig. 5 shows a schematic cross-sectional structure diagram of a third embodiment of the motor rotor of the present invention;

Fig. 6 shows a schematic cross-sectional structure diagram of a fifth embodiment of the motor rotor of the present invention, the viewing direction is the first end face;

Fig. 7 shows a schematic cross-sectional structure diagram of a fifth embodiment of the motor rotor of the present invention, the viewing direction is the second end face;

Fig. 8 shows a schematic assembly diagram of a fifth embodiment of the motor rotor of the present invention;

Fig. 9 shows a partial schematic diagram of a seventh embodiment of the rotor core of the present invention;

Fig. 10 shows a partial schematic diagram of an eighth embodiment of the rotor core of the present invention.

Reference signs:

1-rotating shaft; 11-axis;

12-convex structure; 2-rotor core;

21-permanent magnet; 211-the first permanent magnet;

212-the second permanent magnet; 213-two end side edges of the permanent magnet;

22-mounting hole; 221-groove;

23-Interval area; 24-Anti-leakage magnetic holes;

241-two end side edges of the anti-leakage hole; 25-magnetic field weakening area.

Detailed ways

When the motor is working, the rotor is rotated by the stator and outputs torque to the external machine. In order to increase the torque that the motor shaft can withstand and maintain the reliability of the motor, it is necessary to increase the fixing strength between the rotor shaft and the rotor core. In the present invention, a groove is provided in the mounting hole of the rotor core, and the diameter of the rotating shaft is larger than that of the mounting hole, so that the rotating shaft and the rotor core can realize interference assembly; the groove structure can improve the friction between the mounting hole and the rotating shaft Increase the tangential force between the mounting hole and the rotating shaft, thereby further improving the fixing strength between the rotating shaft and the rotor core, and increasing the torque that can be transmitted between the mounting hole and the rotating shaft.

Further, in the present invention, the rotating shaft of the motor rotor and the rotor core can be assembled by hot pressing process. After the installation is completed, the rotating shaft is formed with a corrugated structure protruding into the groove. The corrugated structure on the rotating shaft and the groove can be clamped in the circumferential direction, the ability to transmit tangential force is further strengthened, the fixing strength between the rotating shaft and the rotor core is further improved, and the bearing capacity of the rotating shaft of the motor is increased. torque.

In order to understand the embodiments of the present invention more clearly, specific embodiments will be described in detail with reference to the accompanying drawings, wherein similar components or identical components are denoted by the same reference numerals.

Referring to Fig. 1, it is a motor rotor in the first embodiment of the present invention, which includes a rotating shaft 1 and a rotor core 2 sleeved on the rotating shaft 1;

Please refer to FIG. 2 , the rotor core 2 includes a plurality of permanent magnets 21 distributed along the circumferential direction and a mounting hole 22 for mounting the rotor core 2 to the rotating shaft 1 , the inner wall of the mounting hole 22 has a concave groove extending in the axial direction. Slot 221. The dotted line in Fig. 2 shows the processing size of the rotating shaft 1. Specifically, before the sheathing, the diameter of the rotating shaft 1 is larger than the diameter of the mounting hole 22, and the depth of the groove 221 is greater than the distance between the diameter of the rotating shaft 1 and the diameter of the mounting hole 22. In the difference, each size refers to the processing size, that is, the processing diameter of the rotating shaft 1 is larger than that of the mounting hole 22, and the distance between the bottom wall of the groove 221 and the axis of the rotating shaft 1 is larger than the diameter of the rotating shaft 1.

The following specifically describes the assembly process of the motor rotor in this embodiment:

Firstly, before installation, the diameter of the rotating shaft 1 is larger than the diameter of the mounting hole 22 , so that the interference fit between the rotating shaft 1 and the mounting hole 22 of the rotor core 2 can be realized. During installation, the rotating shaft 1 can be cooled and shrunk first to reduce the diameter of the rotating shaft 1 , and then the mounting hole 22 of the rotor core 2 is sleeved on the outer side of the rotating shaft 1 . Preferably, at this time, the rotating shaft 1 and the mounting hole 22 are an interference fit. When the temperature of the rotating shaft 1 returns to room temperature, the interference between the rotating shaft 1 and the mounting hole 22 can be increased, and the distance between the rotating shaft 1 and the rotor core 2 High fixing strength. In addition, during installation, the rotor core 2 can also be heated to make it expand, thereby increasing the diameter of the mounting hole 22, and then the mounting hole 22 of the rotor core 2 is sleeved on the outside of the rotating shaft 1. Preferably, the rotating shaft 1 and the mounting hole 22 are an interference fit. When the temperature of the rotor core 2 returns to room temperature, the interference between the shaft 1 and the mounting hole 22 can also be increased, and the fixing strength between the shaft 1 and the rotor core 2 is relatively strong. high.

In this embodiment, as the interference between the rotating shaft 1 and the mounting hole 22 increases, the groove 221 on the inner wall of the mounting hole 22 can also increase the friction between the mounting hole 22 and the rotating shaft 1, and improve the friction between the mounting hole 22 and the rotating shaft. 1, thereby further improving the fixing strength between the rotating shaft 1 and the rotor core 2, and increasing the torque that can be transmitted between the mounting hole 22 and the rotating shaft 1.

Specifically, the depth of the groove is larger than the difference between the diameter of the rotating shaft and the diameter of the installation hole. In this embodiment, the shape of the inner bottom surface of the groove may be a plane or a curved surface, which is not specifically limited. Here, the depth of the groove refers to the depth at the lowest point inside the groove. The depth of the groove needs to be able to accommodate the ribbed structure formed by the shaft.

Please refer to Fig. 3 and Fig. 4, in order to further improve the fixing strength between the rotating shaft 1 and the rotor core 2, and increase the torque that the rotating shaft of the motor can withstand, a second embodiment of the present invention is also provided, which is the same as the first embodiment The motor rotors provided by the above method are basically similar, the only difference is that in this embodiment, it is specifically pointed out that after the installation of the rotating shaft and the rotor core is completed, the convex structure 12 protruding into the groove 221 is formed on the rotating shaft 1 .

In this embodiment, there should be a large difference between the machining diameter of the rotating shaft 1 and the machining diameter of the mounting hole 22 . When installing the rotor, the shaft 1 and the rotor core 2 can be assembled by hot pressing, that is, the rotor core 2 is heated and expanded to increase the diameter of the mounting hole 22, and then the 22 mounting holes of the rotor core 2 are set It is arranged on the outside of the rotating shaft 1; preferably, at this time, the rotating shaft 1 and the mounting hole 22 are an interference fit, and when the temperature of the rotating shaft 1 returns to room temperature, since the diameter of the mounting hole 22 is quite different from the diameter of the rotating shaft 1, as the rotor iron As the temperature of the core 2 decreases, the diameter of the mounting hole 22 gradually recovers, and the rotating shaft 1 is pressed by the mounting hole 22, so that the area of the rotating shaft 1 opposite to the groove 221 of the mounting hole 22 is squeezed into the groove 221, thereby forming a protrusion. The corrugated structure 12 in the groove 221. Alternatively, the rotating shaft 1 and the rotor core 2 can also be assembled by physical press-fitting process, that is, without heating treatment, at normal temperature, physical press-fit assembly is performed to form the corrugated structure 12 protruding into the groove 221 .

In this embodiment, not only the interference between the rotating shaft 1 and the mounting hole 22 is increased, but also the convex corrugated structure 12 on the rotating shaft 1 and the groove 221 can be clamped in the circumferential direction, and the ability to transmit tangential force is further enhanced. The fixing strength between the rotating shaft 1 and the rotor core 2 is further improved, and the torque that the rotating shaft of the motor can bear is increased.

Specifically, the depth of the groove is larger than the difference between the diameter of the rotating shaft and the diameter of the installation hole. In this embodiment, the shape of the inner bottom surface of the groove may be a plane or a curved surface, which is not specifically limited. Here, the depth of the groove refers to the depth at the lowest point inside the groove. The depth of the groove can make the groove accommodate the corrugated structure formed on the rotating shaft.

In addition, in this embodiment, it is only necessary to form the groove 221 in the mounting hole 22 of the rotor core 2, and the rotating shaft 1 is a smooth cylindrical shape. No additional processing is required for the rotating shaft 1, and the manufacturing process is relatively simple. Can improve efficiency.

Considering that the excessive interference between the shaft 1 and the mounting hole 22 of the rotor core 2 may lead to material failure of the shaft 1 and/or the rotor core 2, the gap between the shaft 1 and the rotor core 2 The fitting stress of the hot-press fixing is smaller than the yield strength of the material of the rotating shaft 1 and smaller than the yield strength of the material of the rotor core 2 .

It should be pointed out that the above-mentioned yield strength refers to the yield strength required for material failure, not the deformation strength required for material deformation, and the hot-press fixing fit stress should be greater than the above-mentioned deformation strength but less than the yield strength. In this embodiment, the heat-pressing fixing stress will not cause damage to the material of the rotating shaft 1 and the rotor core 2, thereby ensuring the fixing strength between the rotating shaft 1 and the rotor core 2 and effectively transmitting torque.

Specifically, the above-mentioned hot-press fixing fit stress is calculated according to the following relational formula:

Among them, ΔR is the heat-pressing fit amount between the rotating shaft and the mounting hole, which is determined according to the relational formula ΔR=R _s K _s tR _r K _r t, R _s is the diameter of the rotating shaft, and R _r is the mounting hole The diameter of the hole, R ₂ is the distance between the bottom surface of the anti-leakage hole near the shaft and the axis of the shaft, K _s is the linear expansion rate of the shaft, K _r is the linear expansion rate of the rotor core, t is the ambient temperature, ρ _r is the Poisson's ratio of the rotor core, and ρ _s is the Poisson's ratio of the shaft.

It should be noted that, in this embodiment, the strength of the rotating shaft 1 should be smaller than that of the rotor core 2, so that when the temperature of the rotor core 2 returns to room temperature, the shape of the rotating shaft 1 changes to form a convex groove 221. The corrugated structure 12.

Please refer to Fig. 5. In order to further improve the fixing strength between the rotating shaft 1 and the rotor core 2, on the basis of the first embodiment, a third embodiment of the present invention is also provided. In this embodiment, the rotor core 2. A plurality of grooves 221 are distributed circumferentially along the inner wall of the mounting hole 22.

With the motor rotor provided in this embodiment, since a plurality of grooves 221 are distributed on the inner wall of the mounting hole 22, multiple sets of tangential forces can be provided in the circumferential direction of the rotating shaft 1 when the rotating shaft 1 is assembled in the mounting hole 22, thereby, by This can further improve the fixing strength between the rotating shaft 1 and the rotor core 2 .

Preferably, the above-mentioned plurality of grooves 221 are evenly distributed on the inner wall of the mounting hole 22, and since the tangential force provided by the grooves 221 is distributed evenly in the circumferential direction, the distance between the rotating shaft 1 and the rotor core 2 can also be improved. Uniformity of transmitted torque.

Please continue to refer to FIG. 5, further, in order to facilitate the installation of the permanent magnet 21, on the basis of the third embodiment, a fourth embodiment of the present invention is also provided. In this embodiment, according to the magnetic pole direction of the permanent magnet 21 during installation Differently, the permanent magnet 21 fixed on the rotor core 2 is divided into a first permanent magnet 211 and a second permanent magnet 212, and the first permanent magnet 211 and the second permanent magnet 212 are arranged at intervals from each other. The permanent magnets 211 are opposed one by one, or are respectively opposed to the second permanent magnets 212 one by one.

It should be noted that FIG. 5 only shows a specific implementation manner. In this implementation manner, the grooves 221 are respectively opposite to the first permanent magnets 211 , and the S poles of the first permanent magnets 211 face the direction of the installation hole 22 . Of course, in practical applications, the groove 221 may also be opposite to the permanent magnet 21 whose N pole faces the direction of the rotating shaft 1 .

In this embodiment, the groove 221 is only opposite to one of the first permanent magnet 211 or the second permanent magnet 212. Then, when the above-mentioned permanent magnet 21 is installed on the rotor core 2, the groove 221 is opposed to the groove 221 according to the preset position. If the magnetic poles of the permanent magnets 21 are fixed, the permanent magnets 21 can be installed directly, or the first permanent magnets 211 and the second permanent magnets 212 of the permanent magnets 21 can be spaced from each other. For example, in a specific embodiment shown in FIG. 5 , the permanent magnet 21 whose S pole is set to face the installation hole 22 is opposite to the groove 221 . Then, when assembling the rotor core 2, when encountering the assembly area opposite to the groove 221, the S pole of the permanent magnet 21 is made to face the installation hole 22, and when encountering an assembly area opposite to the groove 221, the permanent magnet 21 is turned toward the installation area. It is sufficient that the N pole of the magnet 21 faces the mounting hole 22 . The installation process is simplified, the assembly efficiency is improved, and the problem of assembly errors due to operator negligence can be reduced. In addition, when the permanent magnet 21 of the rotor core 2 is damaged and needs to be repaired and replaced, the maintenance personnel can directly determine the magnetic pole direction of the permanent magnet 21 according to the position of the groove 221 without additional detection work, which improves work efficiency.

Please refer to Fig. 6 to Fig. 8, on the basis of the first embodiment, a fifth embodiment of the present invention is also provided. In this embodiment, the motor rotor includes two rotor cores 2, and along the circumferential direction, each The center of the groove 221 of the rotor core 2 and the center deviation setting angle of the permanent magnet 21 opposite to the groove 221, observe the motor rotor from the shaft end of the rotating shaft 1, the assembly directions of the two rotor cores 2 are opposite and concave The slots 221 are opposite.

In this embodiment, the assembly directions of the two rotor cores 2 are opposite, as shown in Fig. 6 and Fig. The grooves 221 of the two rotor cores 2 are staggered. Rotate the circumferential direction of the rotor core 2, as shown in FIG. The permanent magnets 21 of the core 2 are offset. Since there is an interval area 23 between two adjacent permanent magnets 21 , the magnetic field at the above interval area 23 is weak, resulting in an uneven magnetic field in the circumferential direction of the rotor core 2 , which easily leads to uneven rotation of the rotor when the motor is working. In the embodiment of the present invention, the permanent magnets 21 of the two rotor cores 2 are staggered, so that the above-mentioned spaced areas 23 can be supplemented each other, so that the magnetic field of the rotor core 2 tends to be uniform in the circumferential direction, and the uniformity of the rotation of the motor rotor is improved. Thereby improving the uniformity of the rotational speed of the motor rotor.

In this embodiment, when the rotor cores 2 are installed, by observing the positions of the grooves 221 and making the grooves 221 of the two rotor cores 2 face each other, the permanent magnets 21 of the two rotor cores 2 can be staggered to facilitate Assembly operations for motor rotors. Specifically, at least the permanent magnet 21 of one rotor core 2 should be able to cover the corresponding interval area 23 of the other rotor core 2 . Design according to requirements, along the circumferential direction, the angle of deviation of the permanent magnets 21 of the two rotor cores 2 is α, then the set angle of the deviation between the center of the groove 221 and the center of the permanent magnet 21 opposite to the groove 221 is

Specifically, the opposite assembly directions of the two rotor cores 2 can be understood as: the end faces of the rotor core 2 are respectively the first end face and the second end face, when one rotor core 2 is assembled, the rotating shaft 1 extends from the direction of the first end face Insert the mounting hole 22 of the rotor core 2, when assembling another rotor core 2, the rotating shaft 1 extends into the mounting hole 22 of the rotor core 2 from the direction of the second end face. In the assembled motor rotor, the second end surface of one rotor core 2 is opposite to the second end surface of the other rotor core 2 , and the assembly directions of the two rotor cores 2 are opposite. FIG. 6 shows the first end surface of the rotor core 2 ; FIG. 7 shows the second end surface of the rotor core 2 .

Please continue to refer to FIG. 9. On the basis of the first embodiment, a sixth embodiment of the present invention is also provided. In this embodiment, on the rotor core 2, in the direction of each permanent magnet 21 facing the installation hole 22, A magnetic leakage prevention hole 24 is also provided, and the bottom wall of the groove 221 is separated from the magnetic flux leakage prevention hole by a set distance.

In this embodiment, providing the anti-leakage hole 24 can reduce the magnetic field of the permanent magnet 21 from diffusing toward the installation hole 22, increase the density of the magnetic field in the working area of the permanent magnet 21, and thus improve the working efficiency of the motor. Specifically, if the groove 221 communicates with the anti-leakage hole or the distance between the bottom wall of the groove 221 and the anti-leakage hole is too small, the strength of the rotor core 2 will be reduced, and it is easy to deform and fail. Therefore, in this embodiment, the bottom wall of the groove 221 is separated from the anti-leakage hole by a set distance, which can improve the strength of the rotor core 2 and increase the service life of the motor rotor.

The rotor core has a weak magnetic area around the permanent magnet and the anti-leakage hole, and the magnetic field line distribution in the weak magnetic area is less, and the magnetic flux density is smaller. The above-mentioned grooves are arranged in the magnetic field weakening area of the rotor core 2 , and have less influence on the magnetic field of the rotor core 2 , so that the rotor has good performance.

In a specific embodiment, the cross-sectional shape of the permanent magnet and the shape of the anti-leakage hole are indeterminate, but the magnetic field weakening region of the rotor core can be determined roughly according to the following method: along the circumferential direction, the two end side edges 213 of the permanent magnet The two end points are point A and point B respectively, and the two end points of the two end side edges 241 of the magnetic flux leakage prevention hole are point C and point D respectively, then, the two end sides of the magnetic flux leakage prevention hole opposite to the groove 221 The extension line of the line connecting point C and point D of edge 241, the extension line of point A and point B line connecting the two end side edges 213 of the permanent magnet adjacent to the groove 221 and the edge line of the mounting hole 22 are surrounded by The region is called the field weakening region 25 , in which the magnetic field generated by the permanent magnet 21 is relatively weak, and the groove 221 is arranged in the field weakening region 25 . In this embodiment, the groove 221 is located in the field-weakening area 25 of the permanent magnet 21 , which has little influence on the magnetic field of the rotor core 2 , so that the rotor has good performance.

Please refer to FIG. 10 , on the basis of the sixth embodiment, a seventh embodiment of the present invention is also provided. In this embodiment, viewed from the shaft end of the rotating shaft 1, the cross-sectional shape of the permanent magnet 21 is rectangular, which prevents magnetic flux leakage. The cross-sectional shape of the hole 24 is roughly an isosceles triangle, then the two end side edges 241 of the anti-leakage hole and the two end side edges 213 of the permanent magnet are straight lines, and the extension line of the two end side edges 213 of the permanent magnet, the anti-magnetic The extension lines of the two end edges 241 of the flux leakage hole and the edge lines of the installation hole 22 define a field weakening area 25 , which is the field weakening area 25 , and the groove 221 is located in the field weakening area 25 .

Specifically, the method of installing the permanent magnets on the rotor core is not limited. For example, the permanent magnets may be bonded to the peripheral side of the rotor core, or the permanent magnets may be embedded in the rotor core from the end surface of the rotor core.

The present invention also provides an electric motor, which includes the electric motor rotor in any of the solutions above. The running reliability of the electric motor is high, and the rotating shaft of the electric motor can bear larger torque.

Specifically, the motor may be a surface permanent magnet (SPM for short) motor, or an interior permanent magnet (IPM for short) motor.

Based on the same inventive concept, the present invention also provides an assembly method for the motor rotor in the above solution. Specifically, in one embodiment, the motor rotor includes a rotating shaft and a rotor core, the rotor core has a mounting hole, and the inner wall of the mounting hole has a groove, wherein the processing diameter of the rotating shaft is larger than the processing diameter of the mounting hole, and the processing depth of the groove is Greater than the difference between the machined diameter of the shaft and the machined diameter of the mounting hole. In this embodiment, the rotating shaft and the rotor core are assembled through a hot pressing process, and the assembly method includes:

The first step is a heating step, heating the rotor core, controlling the heating temperature and duration so that the diameter of the installation hole of the rotating shaft on the rotor core is larger than the machining diameter of the rotating shaft; the second step is the sleeve step, heating the heated The rotor core is sleeved on the outside of the shaft; the third step is the cooling step, cooling the rotor core to room temperature, as the temperature of the rotor core decreases, the rotor core shrinks when cooled, and the diameter of the mounting hole is restored, so that the shaft Under pressure, the area of the rotating shaft opposite to the axially extending groove located on the inner wall of the installation hole is pressed into the groove, forming a corrugated structure protruding into the groove. In this embodiment, the corrugated structure on the rotating shaft and the groove can be clamped in the circumferential direction, the ability to transmit tangential force is further strengthened, and the fixing strength between the rotating shaft and the rotor core is further improved, which can improve the performance of the motor. Torque that the shaft can withstand.

Further, in another embodiment, the motor rotor includes at least two rotor cores; along the circumferential direction, the center of the groove of the rotor core and the center of the permanent magnet opposite to the groove deviate by a set angle, and the sleeve The step specifically includes installing two adjacent rotor cores in opposite directions, and connecting the grooves of the two adjacent rotor cores.

Specifically, the opposite assembly directions of the two rotor cores can be understood as follows: the end faces of the rotor cores are respectively the first end face and the second end face, and when one rotor core is assembled, the rotating shaft extends into the rotor core from the direction of the first end face When assembling another rotor core, the rotating shaft extends into the mounting hole of the rotor core from the direction of the second end face. In the assembled motor rotor, if the second end surface of one rotor core is opposite to the second end surface of the other rotor core, the assembly directions of the two rotor cores are opposite.

In this embodiment, the assembly directions of the two rotor cores are opposite. When the permanent magnets of the two rotor cores face each other, the grooves of the two rotor cores are staggered. Rotate the direction of the rotor cores to make the two rotors The grooves of the iron core are opposite. Then the permanent magnets of the two rotor cores can be staggered. Since there is an interval area between two adjacent permanent magnets, the magnetic field at the above interval area is weak, resulting in an uneven magnetic field of the rotor core in the circumferential direction, and it is easy to cause uneven rotation of the rotor when the motor is working. In the embodiment of the present invention, the permanent magnets of the two rotor cores are staggered, so that the above-mentioned spaced areas can be supplemented with each other, so that the magnetic field of the rotor cores tends to be uniform in the circumferential direction, and the uniformity of the rotation of the motor rotor is improved, thereby improving the motor rotor. Uniformity of rotation speed.

In this embodiment, when installing the rotor cores, by observing the positions of the grooves and connecting the grooves of the two rotor cores, the permanent magnets of the two rotor cores can be staggered, which facilitates the assembly operation of the motor rotor. Specifically, the communication between the grooves of the two rotor cores means that the two grooves only need to have an overlapping portion, and at least the permanent magnet of one rotor core should cover the corresponding interval area of the other rotor core. Of course, in a preferred embodiment, the grooves of the above two rotor cores should face each other, so as to more accurately control the deflection angle of the two rotor cores in the circumferential direction.

Based on the same inventive concept, the present invention also provides another assembling method for the motor rotor in the above solution. Specifically, in one embodiment, the motor rotor includes a rotating shaft and a rotor core, the rotor core has a mounting hole, and the inner wall of the mounting hole has a groove, wherein the processing diameter of the rotating shaft is larger than the processing diameter of the mounting hole, and the processing depth of the groove is Greater than the difference between the machined diameter of the shaft and the machined diameter of the mounting hole. In this embodiment, the rotating shaft and the rotor core are assembled through a physical press-in process, and the assembly method includes:

The pressing step of pressing the rotating shaft into the rotor core. Before pressing in, the diameter of the rotating shaft is larger than the diameter of the mounting hole, and the depth of the groove is greater than the difference between the diameter of the rotating shaft and the diameter of the mounting hole. After pressing in, The area where the rotating shaft is opposite to the groove extending in the axial direction on the inner wall of the mounting hole forms a corrugated structure protruding into the groove.

In this technical solution, the area where the rotating shaft is opposite to the groove can also form a corrugated structure. The corrugated structure on the rotating shaft and the groove can be clamped in the circumferential direction, the ability to transmit tangential force is further strengthened, the fixing strength between the rotating shaft and the rotor core is further improved, and the bearing capacity of the rotating shaft of the motor can be improved. torque.

The specific implementation of the present invention has been described in detail above with reference to the accompanying drawings. Apparently, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.

Claims (17)

1. a kind of motor rotor, including shaft and the rotor core for being sheathed on the shaft, the rotor core is fixed with more A circumferentially distributed permanent magnet, which is characterized in that

The rotor core includes the mounting hole for being arranged the shaft, and the inner wall of the mounting hole is recessed with axially extending Slot, before being arranged, the diameter of the shaft is greater than the aperture of the mounting hole, and the depth of the groove is greater than the shaft Difference between diameter and the aperture of the mounting hole.

2. motor rotor according to claim 1, which is characterized in that the shaft and the rotor core are being arranged Afterwards, the convex stupefied structure protruded into the groove is formed in the shaft region opposite with the groove.

3. motor rotor according to claim 2, which is characterized in that the heat between the shaft and the rotor core It presses secure fit stress to be less than the yield strength of the rotating shaft material, and is less than the yield strength of the rotor core material.

4. motor rotor according to claim 1, which is characterized in that the groove includes the inner wall circumferential direction along mounting hole Multiple grooves of distribution.

5. motor rotor according to claim 4, which is characterized in that the permanent magnet is with the magnetic pole side of adjacent permanent magnet It is arranged to opposite mode, the quantity of the multiple groove and position are arranged to one group of permanent magnetism identical with wherein pole orientation Body is opposite one by one.

6. motor rotor according to claim 1, which is characterized in that along circumferential direction, the center of the groove and with The centre deviation set angle of the opposite permanent magnet of the groove；

The motor rotor includes at least two rotor cores, from the shaft end of the shaft, two neighboring rotor core Assembly direction it is opposite and groove is connected to.

7. motor rotor according to claim 1, which is characterized in that the rotor core further includes corresponding each permanent magnetism The leakproof bore that body is formed, from the shaft end of the shaft from, the cross sectional shape of the leakproof bore is isosceles triangle, and institute The apex angle for stating isosceles triangle is directed toward the center of the permanent magnet, and the cross sectional shape of the permanent magnet is rectangle, described recessed Slot is formed in: the extension line of the extended line of the side at the rectangle both ends, the waist edges such as two of the isosceles triangle, Yi Jisuo State the region that the edge line of mounting hole surrounds.

8. a kind of motor rotor, including shaft and the rotor core for being sheathed on the shaft, the rotor core is fixed with more A circumferentially distributed permanent magnet, which is characterized in that

The rotor core includes the mounting hole for being arranged the shaft, and the inner wall of the mounting hole is recessed with axially extending Slot, the shaft and the rotor core by heat pressing process assemble or physics be pressed into technique assembly, and the shaft with The opposite region of the groove is formed with the convex stupefied structure protruded into the groove.

9. motor rotor according to claim 8, which is characterized in that the heat between the shaft and the rotor core It presses secure fit stress to be less than the yield strength of the rotating shaft material, and is less than the yield strength of the rotor core material.

10. motor rotor according to claim 8, which is characterized in that the groove includes the inner wall week along mounting hole To multiple grooves of distribution.

11. motor rotor according to claim 10, which is characterized in that the permanent magnet is with the magnetic pole of adjacent permanent magnet Contrary mode is arranged, and the multiple number of recesses and position are arranged to one group identical with wherein pole orientation forever Magnet is opposite one by one.

12. motor rotor according to claim 8, which is characterized in that along circumferential direction, the center of the groove and with The centre deviation set angle of the opposite permanent magnet of the groove；

The motor rotor includes at least two rotor cores, from the shaft end of the shaft, two neighboring rotor core Assembly direction it is opposite and groove is connected to.

13. motor rotor according to claim 8, which is characterized in that the rotor core further includes corresponding to each forever The leakproof bore that magnet is formed, from the shaft end of the shaft, the cross sectional shape of the leakproof bore is isosceles triangle, and The apex angle of the isosceles triangle is directed toward the center of the permanent magnet, and the cross sectional shape of the permanent magnet is rectangle, described Groove is formed in: the extension line of the extended line of the side at the rectangle both ends, the waist edges such as two of the isosceles triangle, and The region that the edge line of the mounting hole surrounds.

14. a kind of motor, which is characterized in that including the described in any item motor rotors of such as claim 1~13.

15. a kind of assembly method applied to the motor rotor of claim 1 or 8, which is characterized in that including following step It is rapid:

To the heating stepses that the rotor core is heated, heating temperature and duration make to be arranged described turn on the rotor core The aperture of the mounting hole of axis is greater than the diameter of the shaft；

The rotor core after heating is sheathed on the shaft and is arranged step with form the motor rotor；

The cooling step of the cooling motor rotor, the shaft and the inner wall for being located at the mounting hole simultaneously axially extend The opposite region of groove forms the convex stupefied structure protruded into the groove.

16. assembly method according to claim 15, it is characterised in that:

The heating stepses specifically include: at least two rotor cores of heating, the rotor core, which is fixed with, multiple circumferentially to be divided The permanent magnet of cloth, and along the circumferential direction of the rotor core, the center of the groove and the permanent magnet opposite with the groove Centre deviation set angle；

The step that is arranged specifically includes: the rotor core after heating being sheathed on the shaft respectively, wherein two neighboring turn Sub- iron core is installed in opposite directions, and is connected to the groove of at least two rotor core.

17. a kind of assembly method applied to the motor rotor of claim 1 or 8, which is characterized in that including following step It is rapid:

The shaft is pressed into the indentation step of the rotor core, before indentation, the diameter of the shaft is greater than the peace The aperture in hole is filled, the depth of the groove is greater than the difference between the diameter of the shaft and the aperture of the mounting hole, is pressing After entering, the shaft region formation opposite with the groove for being located at the inner wall of the mounting hole and axially extending protrudes into described recessed Convex stupefied structure in slot.