Motor rotor

Abstract

The invention, which relates to the technical field of the motor, discloses a motor rotor comprising an iron core structure and a rotating shaft. A center hole is formed in the center of the end face, arranged in the axial direction, of the iron core structure in a penetrating mode, a plurality of cooling grooves are formed in the hole wall of the center hole of the iron core structure in the circumferential direction, and the cooling grooves extend in the axial direction of the iron core structure and penetrate through the iron core structure. The rotating shaft penetrates through the center hole to be fixedly connected with the iron core structure, the rotating shaft and the cooling grooves jointly define a plurality of first flow channels, and the first flow channels are used for allowing cooling media flowing out of a speed reducer of the motor to pass through; according to the technical scheme, the first flow channel is defined by the multiple cooling grooves and the rotating shaft together, and when the cooling medium flows through the first flow channel, the position, close to the center hole, of the iron core structure and the rotating shaft are well cooled, so that thermal deformation of the rotor is reduced, the operation stability of the rotor is improved, and rotor abrasion and noise generation are reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of motors, and in particular to a motor rotor. Background Art

[0002] With the rapid development of the new energy vehicle industry, permanent magnet synchronous motors are being used more and more widely in the field of new energy vehicles. With the development of technology, the power density and speed of motors are getting higher and higher, which puts forward new requirements for the cooling of motor rotors. When the motor rotor rotates at high speed, eddy current loss will be generated, causing the rotor to heat up, which in turn reduces the magnetic properties of the magnet, resulting in a decrease in the torque, power, and anti-demagnetization ability of the motor.

[0003] The existing motors are provided with weight-reducing holes that penetrate along the axial direction of the rotor core. When cooling, the cooling medium passes through the weight-reducing holes for cooling. Poor effect will cause thermal deformation of the rotor, thereby generating additional vibration during the movement process, reducing the working efficiency of the equipment, and aggravating the wear of the rotor. In addition, since the motor rotor is a special structure arranged by stacking rotor punching sheets, there are fewer channels for the cooling medium to pass through, the cooling method of the motor rotor is single and the cooling effect is poor. Summary of the invention

[0004] The main purpose of the present invention is to provide a motor rotor, aiming to achieve a good cooling effect.

[0005] To achieve the above-mentioned purpose, the motor rotor proposed in the present invention includes an iron core structure and a rotating shaft; the iron core structure is provided with a center hole at the center of the end face thereof arranged along its axial direction, and the hole wall of the center hole of the iron core structure is provided with a plurality of cooling grooves along its circumference, and each cooling groove extends along the axial direction of the iron core structure and passes through the iron core structure; the rotating shaft passes through the center hole and is fixedly connected to the iron core structure, and the rotating shaft and the plurality of cooling grooves jointly define a plurality of first flow channels, and the first flow channels are used for the cooling medium flowing out of the reducer of the electric motor to pass through.

[0006] In one embodiment, the core structure is provided with a plurality of second hole groups and a plurality of third hole groups along its axially arranged end surface, and the plurality of second hole groups and the plurality of third hole groups are alternately arranged along the circumferential side of the center hole; each second hole group includes two second flow channels that penetrate the core structure along the axial direction of the core structure, and each third hole group includes two third flow channels that penetrate the core structure along the axial direction of the core structure, and the fluid flow direction of the second flow channel is opposite to the fluid flow direction of the third flow channel; each second flow channel and each third flow channel are connected to the first flow channel.

[0007] In one embodiment, the motor rotor also includes two magnetic isolation plates, which are relatively arranged at the two ends of the core structure along its axial direction and are against the core structure. At least one first connecting groove and multiple second connecting grooves are formed on the end surfaces of the two magnetic isolation plates facing each other. The first connecting groove is located in the middle of the magnetic isolation plate and is connected to the first flow channel. Some of the multiple second connecting grooves are connected to the second flow channel, and the remaining parts are connected to the third flow channel. The two magnetic isolation plates include a first magnetic isolation plate and a second magnetic isolation plate. In the first magnetic isolation plate, a connecting groove is arranged between the multiple second connecting grooves connected to the second flow channel and the first connecting groove, and the multiple second connecting grooves connected to the third flow channel are through-arranged. In the second magnetic isolation plate, a connecting groove is arranged between the multiple second connecting grooves connected to the third flow channel and the first connecting groove, and the multiple second connecting grooves connected to the second flow channel are through-arranged.

[0008] In one embodiment, each second connecting groove is connected to two second flow channels in the second hole group or two third flow channels in the third hole group.

[0009] In one embodiment, the size of the second communicating groove matches the size of the corresponding second flow channel or the third flow channel.

[0010] In one embodiment, the cross-sectional area of ​​the second communicating groove arranged through-through is arranged to decrease along the fluid flow direction.

[0011] In one embodiment, the rotating shaft has an inlet channel extending along the axial direction of the rotating shaft. A plurality of radial flow diversion holes are opened on the circumference of the rotating shaft, and each radial flow diversion hole is respectively connected to the first flow channel and the inlet channel.

[0012] In one embodiment, a front bearing oblique oil hole and a rear bearing oblique oil hole are respectively opened at the two ends of the axial arrangement of the rotating shaft. One end of the front bearing oblique oil hole is connected to the inlet channel, and the other end is used to correspond to the front bearing of the motor. One end of the rear bearing oblique oil hole is connected to the inlet channel, and the other end is used to correspond to the rear bearing of the motor.

[0013] In one embodiment, the core structure includes an iron core and a plurality of magnets; the iron core forms a plurality of magnet holes, and a center hole is set in the middle of the iron core; the plurality of magnets are inserted one by one into the plurality of magnet holes, and each magnet and the hole wall of the magnet hole jointly define a second flow channel or a third flow channel.

[0014] In one embodiment, each magnetic steel includes a plurality of magnetic steel segments arranged in a staggered manner along the axial direction of the core structure.

[0015] The technical solution of the present invention defines a first flow channel through multiple cooling grooves and a rotating shaft. When the cooling medium flows through the first flow channel, the position of the core structure close to the center hole and the rotating shaft are well cooled to reduce thermal deformation of the rotor, improve rotor operation stability, and reduce rotor wear and noise generation. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0017] Figure 1 A schematic diagram of the overall structure of an embodiment of a motor rotor provided by the present invention;

[0018] Figure 2 for Figure 1 A cross-sectional view of the motor rotor along the axial direction;

[0019] Figure 3 for Figure 1 Schematic diagram of the cross section of the rotating shaft;

[0020] Figure 4 for Figure 1 Schematic diagram of the cross section of the core structure;

[0021] Figure 5 for Figure 1 A schematic diagram of the structure of the first magnetic isolation plate;

[0022] Figure 6 A schematic diagram of the flow direction of the cooling medium in an embodiment of the motor rotor provided by the present invention.

[0023] Description of Figure Numbers:

[0024] 100. Motor rotor; 1. Core structure; 11. Core; 111. Center hole; 112. Cooling groove; 113. First flow channel; 114. Magnetic steel hole; 115. Second flow channel; 116. Third flow channel; 117. Small round hole; 118. Weight reduction hole; 118A. Marking groove; 12. Magnetic steel; 2. Rotating shaft; 21. Inlet channel; 22. Radial diverter hole; 23. Front bearing oblique oil hole; 24. Rear bearing oblique oil hole; 3. Magnetic isolation plate; 31. First connecting groove; 32. Connecting groove; 331. Second connecting groove (through); 332. Second connecting groove (not through); 34. Positioning groove.

[0025] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0028] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of the features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0029] With the rapid development of the new energy vehicle industry, permanent magnet synchronous motors are being used more and more widely in the field of new energy vehicles. With the development of technology, the power density and speed of motors are getting higher and higher, which puts forward new requirements for the cooling of motor rotors. When the motor rotor rotates at high speed, eddy current loss will be generated, causing the rotor to heat up, which in turn reduces the magnetic properties of the magnet, resulting in a decrease in the torque, power, and anti-demagnetization ability of the motor.

[0030] The existing motors are provided with weight-reducing holes that penetrate along the axial direction of the rotor core. When cooling, the cooling medium passes through the weight-reducing holes for cooling. Poor effect will cause thermal deformation of the rotor, thereby generating additional vibration during the movement process, reducing the working efficiency of the equipment, and aggravating the wear of the rotor. In addition, since the motor rotor is a special structure arranged by stacking rotor punching sheets, there are fewer channels for the cooling medium to pass through, and the cooling method of the motor rotor is single.

[0031] Based on this, the present application proposes a motor rotor 100 to achieve a good cooling effect.

[0032] In one embodiment of the present invention, please refer to Figure 1 , Figure 2 and Figure 4 The motor rotor 100 includes an iron core structure 1 and a rotating shaft 2; a center hole 111 is provided at the center of the end face of the iron core structure 1 arranged along its axial direction, and a hole wall of the center hole 111 of the iron core structure 1 is provided with a plurality of cooling grooves 112 along its circumferential direction, and each cooling groove 112 extends along the axial direction of the iron core structure 1 and is arranged through the iron core structure 1; the rotating shaft 2 passes through the center hole 111 and is fixedly connected to the iron core structure 1, and the rotating shaft 2 and the plurality of cooling grooves 112 jointly define a plurality of first flow channels 113, and the first flow channels 113 are used for the cooling medium flowing out of the reducer of the electric motor to pass through.

[0033] The technical solution of the present invention defines a first flow channel 113 together with a plurality of cooling grooves 112 and the rotating shaft 2. When the cooling medium flows through the first flow channel 113, the core structure 1 near the center hole 111 and the rotating shaft 2 are well cooled to reduce thermal deformation of the rotor, improve rotor operation stability, and reduce rotor wear and noise generation.

[0034] There is no restriction on the shape and size of the cooling groove 112 , and its cross section may be square, arc-shaped or other shapes. When designing its shape and size, the motor rotor 100 is required to achieve a good cooling effect and meet the strength requirements of the motor rotor 100 .

[0035] It should be noted that the size of the center hole 111 needs to be compatible with the size of the rotating shaft 2, and an interference fit can be achieved for reliable connection. The flow channel is a channel for passing a cooling medium, and the cooling medium includes air, cooling oil, a water-based solution or other fluids. The cooling medium flowing out of the reducer of the motor is a cooling medium that flows out for cooling the outer splines of the reducer. In this embodiment, the connection method between the reducer of the motor and the first flow channel 113 is not limited.

[0036] In one embodiment of the present invention, please refer to Figure 4 and Figure 6(The direction of the arrow in the figure is the flow direction of the cooling medium), the core structure 1 is provided with a plurality of second hole groups and a plurality of third hole groups along its axially arranged end face, and the plurality of second hole groups and the plurality of third hole groups are alternately arranged along the circumferential side of the center hole 111; each second hole group includes two second flow channels 115 that penetrate the core structure 1 along the axial direction of the core structure 1, and each third hole group includes two third flow channels 116 that penetrate the core structure 1 along the axial direction of the core structure 1, and the fluid flow direction of the second flow channel 115 is opposite to the fluid flow direction of the third flow channel 116; each second flow channel 115 and each third flow channel 116 are connected to the first flow channel 113. With such arrangement, the cooling medium cools the inside of the battery core structure when passing through the first flow channel 113, and cools the peripheral part of the center hole 111 when passing through the second flow channel 115 or the third flow channel 116. The first flow channel 113, the second flow channel 115 and the third flow channel 116 all penetrate the core structure 1 axially, providing a longer tortuous cooling flow channel with good heat dissipation effect; the cooling medium in the second flow channel 115 flows from one end to the other end of the motor rotor 100, and the temperature of the cooling medium gradually increases along the flow direction of the cooling medium, while the cooling medium in the adjacent third flow channel 116 flows in the opposite direction to the cooling medium in the second flow channel 115, realizing convection, and the temperature of the cooling medium also gradually increases along the flow direction of the cooling medium in the third flow channel 116, so that the temperature of the cooling medium is evenly distributed along the axial direction of the motor, and the motor rotor 100 is evenly cooled.

[0037] Specifically, in each second hole group, the two second flow channels 115 extend along the direction from the edge of the core structure 1 toward the center of the core structure 1 and are arranged close to each other; in each third hole group, the two third flow channels 116 extend along the direction from the edge of the core structure 1 toward the center of the core structure 1 and are arranged close to each other, and in the cross section of the core structure 1, the two second flow channels 115 in the second hole group or the two third flow channels 116 in the third hole group form a "V" shape.

[0038] In one embodiment of the present invention, please refer to Figure 5 and Figure 6The motor rotor 100 also includes two magnetic isolation plates 3, which are relatively arranged at the two ends of the core structure 1 along its axial direction and are against the core structure 1. A first connecting groove 31 and a plurality of second connecting grooves are formed on the end surfaces of the two magnetic isolation plates 3 facing each other. The first connecting groove 31 is located in the middle of the magnetic isolation plate 3 and is connected to the first flow channel 113. Part of the plurality of second connecting grooves is connected to the second flow channel 115, and the remaining part is connected to the third flow channel 116; the two magnetic isolation plates 3 include a first magnetic isolation plate and a second magnetic isolation plate. In the first magnetic isolation plate, a connecting groove 32 is arranged between the plurality of second connecting grooves 332 connected to the second flow channel 115 and the first connecting groove 31, and the plurality of second connecting grooves 331 connected to the third flow channel 116 are through-arranged. In the second magnetic isolation plate, a connecting groove 32 is arranged between the plurality of second connecting grooves 332 connected to the third flow channel 116 and the first connecting groove 31, and the plurality of second connecting grooves 331 connected to the second flow are through-arranged. With such arrangement, the cooling medium has two flow directions, one of which is: passing through the first flow channel 113, the first connecting groove 31 on the first magnetic isolation plate, the connecting groove 32 on the first magnetic isolation plate, the second connecting groove 332 on the first magnetic isolation plate, the third flow channel 116, and the second connecting groove 331 which is set through the second magnetic isolation plate in sequence; the other flow direction is: passing through the first flow channel 113, the first connecting groove 31 on the second magnetic isolation plate, the connecting groove 32 on the second magnetic isolation plate, the second connecting groove 332 on the second magnetic isolation plate, the second flow channel 115, and the second connecting groove 331 which is set through the first magnetic isolation plate in sequence, so as to realize the convection of the cooling medium; and the second connecting groove 331 which is set through is located at the end faces of the two magnetic isolation plates 3, and is thrown to the inner side of the winding of the motor stator when flowing out, so that the motor stator winding can also be cooled in both directions.

[0039] Specifically, the first magnetic isolation plate is the same as the second magnetic isolation plate, but during installation, the second connecting groove 331 that penetrates the first magnetic isolation plate is arranged opposite to the second connecting groove 332 that does not penetrate the second magnetic isolation plate, and the second connecting groove 332 that does not penetrate the first magnetic isolation plate is arranged opposite to the second connecting groove 331 that penetrates the second magnetic isolation plate.

[0040] In a feasible embodiment, an annular first communicating groove 31 is formed on the magnetic isolation plate 3, and the first communicating groove 31 is connected to the plurality of first flow channels 113. In this way, the cooling medium of the plurality of first flow channels 113 is mixed when entering the same communicating groove, and has the same temperature when it is divided and flows into each second flow channel 115 or third flow channel 116 again, so that uniform cooling is performed.

[0041] In another feasible embodiment, a plurality of first connecting grooves 31 are formed on the magnetic isolation plate 3, each first connecting groove 31 corresponds to a first flow channel 113, and the first flow channel 113 corresponds to the second flow channel 115 or the third flow channel 116 relative to the rotating shaft 2, and the non-through second connecting groove 332 is connected to the second flow channel 115 or the third flow channel 116 corresponding to the first flow channel 113, and the connecting groove 32 extends on the magnetic isolation plate 3 to connect the above-mentioned second connecting groove 332 and the second connecting groove 33. If the motor rotor 100 generates heat unevenly, the left side of the motor rotor 100 centered on the rotating shaft 2 generates high heat, while the right side generates low heat. In this arrangement, the cooling medium passing through the first flow channel 113 on the left side of the motor rotor 100 flows to the second flow channel 115 or the third flow channel 116 on the right side of the motor rotor 100, and the cooling medium passing through the first flow channel 113 on the right side of the motor rotor 100 flows to the second flow channel 115 or the third flow channel 116 on the right side of the motor rotor 100, thereby achieving uniform heat dissipation and having a longer connecting groove 32, which can also cool the end of the battery core structure.

[0042] Furthermore, the motor rotor 100 is provided with a weight-reducing hole 118 extending axially through the cell structure between the central hole 111 and the second flow channel 115 or the third flow channel 116 . The weight-reducing hole 118 is connected to the first connecting groove 31 to further cool the motor rotor 100 .

[0043] In one embodiment of the present invention, each second connecting groove is connected to two second flow channels 115 in the second hole group or two third flow channels 116 in the third hole group. In this way, one end of the two second flow channels 115 in each second hole group is connected to the same second connecting groove, and one end of the two third flow channels 116 in each third hole group is connected to the same second connecting groove.

[0044] The number of the second connecting grooves on the first magnetic isolation plate and the second magnetic isolation plate is reduced, the energy loss of the cooling medium is reduced, and the process difficulty is reduced.

[0045] In one embodiment of the present invention, the size of the second communication groove is matched with the size of the corresponding second flow channel 115 or the third flow channel 116. Such a configuration makes it possible for the cooling medium in the second flow channel 115 or the third flow channel 116 to have a smaller pressure loss when entering the second communication groove, and makes it possible for the cooling medium in the second communication groove to have a smaller pressure loss when entering the second flow channel 115 or the third flow channel 116, thereby reducing the pressure requirement for the cooling medium when entering the motor rotor 100.

[0046] In a feasible embodiment, the two second flow channels 115 in each second hole group or the two third flow channels 116 in each third hole group correspond to a second connecting groove. If the second connecting groove is connected to the two second flow channels 115, its channel cross-sectional size is equal to the channel cross-sectional size of the two second flow channels 115, and the two second flow channels 115 can be smoothly connected at the same time. If the second connecting groove is connected to the two third flow channels 116, its channel cross-sectional size is equal to the channel cross-sectional size of the two third flow channels 116, and the two third flow channels 116 can be smoothly connected at the same time.

[0047] In one embodiment of the present invention, the cross-sectional area of ​​the second connecting groove 331 is reduced along the fluid flow direction. This arrangement can increase the flow rate of the cooling medium flowing out of the second connecting groove 331, while reducing the temperature of the cooling medium flowing out, so that the cooling medium has an ideal flow rate and temperature to cool the winding.

[0048] In a feasible embodiment, the second connecting groove 331 arranged through-through has a first groove section and a second groove section away from the core structure 1, the size of the first groove section is adapted to the size of the corresponding second flow channel 115 or the third flow channel 116, and the size of the second groove section is smaller than the size of the first groove section.

[0049] In another feasible embodiment, the cross-sectional area of ​​the through-going second connecting groove 331 is gradually reduced along the fluid flow direction, and the cross-sectional area of ​​the second connecting groove 331 close to the iron core 11 is adapted to the size of the corresponding second flow channel 115 or third flow channel 116 .

[0050] In one embodiment of the present invention, please refer to Figure 2 The rotating shaft 2 has an inlet channel 21, which extends along the axial direction of the rotating shaft 2. A plurality of radial diverter holes 22 are provided on the circumferential side of the rotating shaft 2. Each radial diverter hole 22 is connected to the first flow channel 113 and the inlet channel 21. In this way, the cooling medium passes through the inlet channel 21 and is diverted to each first flow channel 113 through the radial diverter holes 22 to achieve uniform distribution of the cooling medium.

[0051] It should be noted that the rotating shaft 2 has an output end, and the inlet channel 21 of the output end of the rotating shaft 2 is provided with an internal spline, which cooperates with the external spline of the reducer, and the cooling medium flowing out of the external spline of the reducer enters the inlet channel 21 of the rotating shaft 2.

[0052] In a feasible embodiment, one end of the radial diversion hole 22 is connected to the center position of the hole section of the first flow channel 113, so that the flow length of the cooling medium flowing along the first flow channel 113 to the two ends of the rotating shaft 2 (the length of the radial diversion hole 22 reaching the second flow channel 115 and the length of the radial diversion hole 22 reaching the third flow channel 116) are equal to achieve uniform cold cutting.

[0053] See also Figure 6 In one embodiment of the present invention, the rotating shaft 2 is provided with a front bearing oblique oil hole 23 and a rear bearing oblique oil hole 24 at the two ends of the axial arrangement thereof, one end of the front bearing oblique oil hole 23 is connected to the inlet channel 21, and the other end is used to correspond to the front bearing of the motor, and one end of the rear bearing oblique oil hole 24 is connected to the inlet channel 21, and the other end is used to correspond to the rear bearing of the motor. With such an arrangement, while the motor rotor 100 is oil-cooled, the lubricating oil flow is divided to the front bearing and the rear bearing at the front and rear of the motor through the arrangement of the front bearing oblique oil hole 23 and the rear bearing oblique oil hole 24, so as to lubricate the front bearing and the rear bearing respectively.

[0054] Wherein, the cooling medium is selected as lubricating oil.

[0055] It should be noted that the front bearing and the rear bearing of the motor are sleeved on both ends of the rotating shaft 2 along its axial direction to support the rotating shaft 2 and reduce the friction during its rotation.

[0056] In one embodiment of the present invention, please refer to Figure 4 The iron core 11 forms a plurality of magnetic steel holes 114, and a central hole 111 is provided in the middle of the iron core 11; a plurality of magnetic steels 12 are inserted into the plurality of magnetic steel holes 114 one by one, and each magnetic steel 12 and the hole wall of the magnetic steel hole 114 jointly define a second flow channel 115 or a third flow channel 116. In this way, the hole wall of the magnetic steel hole 114 and the magnetic steel 12 jointly define the second flow channel 115 or the third flow channel 116, so that the cooling medium can directly contact the magnetic steel 12 for cooling, thereby improving the cooling effect on the magnetic steel 12.

[0057] Accordingly, when assembling the core structure 1, the magnetic steel 12 slot cannot be injection molded, and the magnetic steel 12 needs to be installed in the magnetic steel 12 slot of the rotor core 11 by gluing or mechanical fixing, thereby leaving space to form the second flow channel 115 or the third flow channel 116.

[0058] In one embodiment of the present invention, each magnetic steel 12 includes a plurality of magnetic steel segments arranged in a staggered manner along the axial direction of the core structure 1. In this way, the plurality of magnetic steel segments are arranged in a staggered manner, and the contact area between the cooling medium in the second flow channel 115 or the third flow channel 116 and the groove of the magnetic steel 12 is larger, and the cooling effect is better.

[0059] Furthermore, along the axial direction of the core 11 , multiple segments of magnetic steel 12 are arranged in staggered slots to form a “V”-shaped magnetic pole on the axial interface of the core structure 1 .

[0060] Specifically, during assembly, a plurality of punching sheets are stacked along the axial direction of the punching sheets to form the iron core 11, and then a plurality of magnetic steel segments are formed by staggering the stacked iron cores 11 along the axial direction of the iron core 11.

[0061] See also Figure 4 The punching sheet has two mutually perpendicular center lines (the center lines are indicated by unmarked arrows in the figure), and there are two pairs of small circular holes 117 on the rotor core 11, one pair forms an angle a with the center line (the direction of the connection line of the two small circular holes is indicated by an arrow marked a in the figure), and the other pair forms an angle b with the other center line (the direction of the connection line of the two small circular holes is indicated by an arrow marked b in the figure); there are a number of weight-reducing holes 118 on the punching sheet, and the weight-reducing hole 118 has two marking grooves 118A in the straight line direction of the pair of small circular holes 117 with an included angle of a, and has one marking groove 118A in the straight line direction of the pair of small circular holes 117 with an included angle of b, and the position of the marking groove 118A is not on the symmetrical center line, so as to facilitate the determination of the front and back of the punching sheet; and a pair of positioning grooves 34 are provided on the inner end surface of the magnetic isolation plate 3 close to the core structure 1. With such arrangement, when assembling and press-fitting the first stack of iron cores 11, the pair of small circular holes 117 at angle a are aligned with the positioning groove 34 of the magnetic isolation plate 3; when press-fitting the second stack of iron cores 11, the pair of small circular holes 117 at angle b are aligned with the positioning groove 34 of the magnetic isolation plate 3; when press-fitting the third stack of iron cores 11, the iron cores 11 are first turned over, and then the pair of small circular holes 117 at angle b are aligned with the positioning groove 34 of the magnetic isolation plate 3; when press-fitting the fourth stack of iron cores 11, the iron cores 11 are first turned over, and then the pair of small circular holes 117 at angle a are aligned with the positioning groove 34 of the magnetic isolation plate 3; the fifth stack is the same as the fourth stack, the sixth stack is the same as the third stack, the seventh stack is the same as the second stack, and the eighth stack is the same as the first stack. In this way, the motor rotor 100 forms a plurality of stacked cores 11 with the angles of the small circular holes 117 and the positioning grooves 34 of the magnetic isolation plate 3 being a, b, -b, -a, -a, -b, b, a in sequence, thus forming a plurality of staggered magnetic steel segments, i.e., "V"-shaped oblique poles. When stacking the second magnetic isolation plate, rotate it 90° relative to the first magnetic isolation plate so that it is aligned with the pair of small circular holes 117 at angle b on the eighth stacked core 11 and the positioning grooves 34 of the magnetic isolation plate 3, and finally press the steel ring onto the rotating shaft 2, and axially fix and tighten the motor rotor 100 through interference fit.

[0062] In one embodiment of the present invention, four second hole groups and four third hole groups are alternately arranged along the circumferential side of the center hole 111, the second hole group is formed by two N-pole magnetic steels 12 inserted in the corresponding magnetic steel holes 114, and the third hole group is formed by two S-pole magnetic steels 12 inserted in the corresponding magnetic steel holes 114. Correspondingly, four through second connecting grooves 331 and four non-through second connecting grooves 332 are arranged on each magnetic isolation plate 3, one end of each second hole group corresponding to the N-pole magnetic steel 12 is connected to a non-through second connecting groove 332 on the first magnetic isolation plate, and the other end is connected to a through second connecting groove 331 on the second magnetic isolation plate, and one end of each third hole group corresponding to the S-pole magnetic steel 12 is connected to a non-through second connecting groove 332 on the second magnetic isolation plate, and the other end is connected to a through second connecting groove 331 on the first magnetic isolation plate.

[0063] As a result, the cooling medium has the following flow direction:

[0064] 1. The center hole of the outer spline of the reducer - the inlet channel 21 - the radial flow diversion hole 22 - the first flow channel 113 - the first connecting groove 31 on the first magnetic isolation plate - the connecting groove 32 on the first magnetic isolation plate - the second connecting groove 332 that is not through on the first magnetic isolation plate - the second hole group corresponding to the N-pole magnetic steel - the through second connecting groove 331 on the second magnetic isolation plate - the outflow cooling stator winding on one side of the second magnetic isolation plate;

[0065] 2. The center hole of the outer spline of the reducer - the inlet flow channel 21 - the radial diverter hole 22 - the first flow channel 113 - the first connecting groove 31 on the second magnetic isolation plate - the connecting groove 32 on the second magnetic isolation plate - the second connecting groove 332 that is not through on the second magnetic isolation plate - the second hole group corresponding to the N-pole magnetic steel - the through second connecting groove 331 on the first magnetic isolation plate - the outflow on one side of the first magnetic isolation plate to cool the stator winding;

[0066] 3. Reducer external spline center hole - inlet channel 21 - front bearing oblique oil hole 23;

[0067] 4. Reducer external spline center hole - inlet channel 21 - rear bearing oblique oil hole 24.

[0068] The above description is only an exemplary embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A motor rotor, characterized in that: include: An iron core structure, wherein a center hole is provided through the center of an end surface of the iron core structure arranged along the axial direction thereof, and a hole wall of the center hole of the iron core structure is provided with a plurality of cooling grooves along its circumference, each of the cooling grooves extending along the axial direction of the iron core structure and penetrating the iron core structure; and, A rotating shaft passes through the central hole and is fixedly connected to the core structure. The rotating shaft and the plurality of cooling grooves together define a plurality of first flow channels, and the first flow channels are used for the cooling medium flowing out of the reducer of the electric machine to pass through.

2. The motor rotor according to claim 1, characterized in that: The core structure is provided with a plurality of second hole groups and a plurality of third hole groups along the axial end surface thereof, and the plurality of second hole groups and the plurality of third hole groups are alternately arranged along the circumference of the central hole; Each of the second hole groups includes two second flow channels penetrating the core structure along the axial direction of the core structure, and each of the third hole groups includes two third flow channels penetrating the core structure along the axial direction of the core structure, and the fluid flow direction of the second flow channel is opposite to the fluid flow direction of the third flow channel; Each of the second flow channels and each of the third flow channels are communicated with the first flow channel.

3. The motor rotor according to claim 2, characterized in that: The motor rotor further comprises two magnetic isolation plates, which are arranged at two ends of the core structure along the axial direction thereof and are opposed to the core structure. At least one first connecting groove and a plurality of second connecting grooves are formed on the end surfaces of the two magnetic isolation plates facing each other. The first connecting groove is located in the middle of the magnetic isolation plates and is connected to the first flow channel. Part of the plurality of second connecting grooves is connected to the second flow channel, and the remaining part is connected to the third flow channel. The two magnetic isolation plates include a first magnetic isolation plate and a second magnetic isolation plate. In the first magnetic isolation plate, a connecting groove is arranged between the multiple second connecting grooves connected to the second flow channel and the first connecting groove, and the multiple second connecting grooves connected to the third flow channel are arranged in a through-type arrangement. In the second magnetic isolation plate, a connecting groove is arranged between the multiple second connecting grooves connected to the third flow channel and the first connecting groove, and the multiple second connecting grooves connected to the second flow channel are arranged in a through-type arrangement.

4. The motor rotor according to claim 3, characterized in that: Each of the second connecting grooves is connected to two second flow channels in the second hole group or two third flow channels in the third hole group.

5. The motor rotor according to claim 3, characterized in that: The size of the second communicating groove matches the size of the corresponding second flow channel or the third flow channel.

6. The motor rotor according to claim 3, characterized in that: The cross-sectional area of ​​the second communicating groove arranged through the fluid is reduced along the fluid flow direction.

7. The motor rotor according to claim 2, characterized in that: The rotating shaft has an inlet channel, which extends along the axial direction of the rotating shaft. A plurality of radial flow diversion holes are opened on the circumferential side of the rotating shaft, and each of the radial flow diversion holes is communicated with the first flow channel and the inlet channel respectively.

8. The motor rotor according to claim 7, characterized in that: The rotating shaft is respectively provided with a front bearing oblique oil hole and a rear bearing oblique oil hole at the positions of the two ends of its axial arrangement. One end of the front bearing oblique oil hole is connected to the inlet channel, and the other end is used to correspond to the front bearing of the motor. One end of the rear bearing oblique oil hole is connected to the inlet channel, and the other end is used to correspond to the rear bearing of the motor.

9. The motor rotor according to claim 2, characterized in that: The core structure comprises: An iron core is formed with a plurality of magnetic steel holes, wherein the center hole is arranged in the middle of the iron core; and A plurality of magnetic steels are inserted one by one into the plurality of magnetic steel holes, and each of the magnetic steels and the hole wall of the magnetic steel hole jointly define the second flow channel or the third flow channel.

10. The motor rotor according to claim 9, characterized in that: Each of the magnetic steels includes a plurality of magnetic steel segments arranged in a staggered manner along the axial direction of the core structure.

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