Cooling system for oil cooling of motor rotor

Abstract

Provided in the present invention is a cooling system for oil cooling of a motor rotor. The cooling system comprises a rotor shaft, balancing plates, and an iron core assembly, wherein an inner hole is formed at one end of the rotor shaft, and two groups of oil holes are provided in a side wall of the rotor shaft and extend through same to the inner hole; the two balancing plates are connected to the side wall of the rotor shaft respectively at positions where the two groups of oil holes are formed, and each balancing plate is provided with inlet oil grooves in communication with the oil holes and outlet oil grooves provided in a penetrating manner; an oil channel is provided in an axial direction of each single iron core in the iron core assembly, and communicates the inlet oil groove and the outlet oil groove of the two balancing plates at the two ends of the single iron core; and cooling oil entering the inner hole enters the inlet oil grooves of the balancing plates along the oil holes of the rotor shaft, then enters the oil channels of the iron cores through the inlet oil grooves, and finally flows along the oil channels and flows out through the outlet oil grooves. In the present invention, cooling oil enters an iron core assembly inside a motor rotor for cooling, and the cooling oil flows in a symmetrical oil circuit of a motor rotor structure in opposite directions or in the same direction, so as to achieve the aim of introducing cooling oil into the motor rotor and achieving sufficient cooling.

Description

A motor rotor oil cooling system Technical Field

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

[0002] Passenger vehicles have entered the era of electrification, and oil-cooled motors have become a mainstream technology for electric vehicle drive systems. Traditionally, e-axle motors in passenger cars have been cooled and dissipated through water channels outside the motor housing, resulting in high thermal resistance and limited heat dissipation. Oil cooling of motors directs the cooling lubricant through the motor's interior and sprays it onto the motor surface, reducing thermal resistance and increasing the heat dissipation area. This improves cooling efficiency and e-axle performance.

[0003] For permanent magnet synchronous motors, the permanent magnet steel inside the motor rotor is one of the thermal bottlenecks. In order to fully utilize the advantages of oil cooling, it is of great significance to introduce cooling oil into the rotor and fully cool the rotor.

[0004] Summary of the Invention

[0005] In view of the shortcomings of the prior art described above, the present invention provides a motor rotor oil cooling system. By opening an oil circuit in the motor rotor structure, cooling oil is allowed to enter the iron core group inside the motor rotor for cooling, and the cooling oil flows in the symmetrical oil circuit of the motor rotor structure to solve the problem of introducing the cooling oil into the interior of the motor rotor for cooling and ensuring that the cooling oil sufficiently cools the motor rotor.

[0006] The present invention provides an oil-cooling system for a motor rotor, comprising a rotor shaft, a balancing disk and an iron core group. An inner hole is formed at one end of the rotor shaft, and two groups of oil holes are formed on the side wall of the inner hole; two balancing disks are respectively connected to the side walls of the rotor shaft where the two groups of oil holes are formed, and an inlet oil groove communicating with the oil holes and an outlet oil groove passing through the balancing disks are formed on the balancing disks; the iron core group is arranged around the circumferential outer side of the rotor shaft and is located between the two balancing disks, and the two ends of the iron core group are respectively connected to the two balancing disks. Several oil channels are provided in the group, which connect the inlet oil grooves and outlet oil grooves of the two balancing discs at both ends of the core unit. The cooling oil entering the inner hole enters the inlet oil groove of the balancing disc along the oil hole of the rotor shaft, then enters the oil channel of the core group through the inlet oil groove, and finally flows out through the outlet oil groove along the oil channel. The same end of adjacent oil channels is connected to the inlet oil groove and the outlet oil groove respectively, or to the two inlet oil grooves or the two outlet oil grooves respectively. In this way, the cooling oil can flow in opposite directions or in the same direction in adjacent oil channels.

[0007] In one embodiment of the present invention, the two groups of oil holes are evenly arranged on the side wall of the inner hole of the rotor shaft and are equal in number. The number of oil holes is equal to the number of iron core units in the iron core group; in terms of the circumferential angle of the rotor shaft, the angular difference between any adjacent oil holes in the two groups of oil holes is equal.

[0008] In one embodiment of the present invention, on a single balancing disk at one end of the core assembly, the same number of inlet oil grooves and outlet oil grooves are alternately arranged, and the sum of the number of the inlet oil grooves and the outlet oil grooves is equal to the number of core units.

[0009] In one embodiment of the present invention, at least one oil channel is defined in the core unit, and the plurality of oil channels are symmetrical about the circumference of the core assembly.

[0010] In one embodiment of the present invention, when the number of oil channels of the core unit is an odd number, the inlet oil groove and the outlet oil groove are respectively located at the two ends of the core unit; when the number of oil channels of the core unit is an even number, the inlet oil groove and the outlet oil groove are located at the same end of the core unit.

[0011] In one embodiment of the present invention, when the number of oil passages of the core unit is greater than one, a return oil groove is further provided on the balancing plate, and the return oil groove is connected to adjacent oil passages of the core unit.

[0012] In one embodiment of the present invention, an end of the outlet oil tank facing away from the core assembly faces the stator end winding of the motor.

[0013] In one embodiment of the present invention, in the core assembly, on the balancing disks at both ends of at least one pair of axially symmetrical core units, when the inlet oil groove and the outlet oil groove are located at the same end of the core unit; on the balancing disk at one end of the core unit, the end of the outlet oil groove facing away from the core unit is closed and connected to the inlet oil groove; on the balancing disk at the other end of the core unit, the outlet oil groove is opened on the return oil groove; so as to change the number of outlet oil grooves at both ends of the core assembly.

[0014] In one embodiment of the present invention, in the core group, on the balancing disks at both ends of at least one pair of axially symmetrical core units, when the inlet oil groove and the outlet oil groove are respectively located at the two ends of the core unit; on the balancing disk located at one end of the core unit, the end of the outlet oil groove facing away from the core unit is closed and connected to the return oil groove; on the balancing disk located at the other end of the core unit, the outlet oil groove is opened on the balancing disk, and the return oil groove is connected to the outlet oil groove or the inlet oil groove; thereby changing the number of outlet oil grooves at both ends of the core group.

[0015] In one embodiment of the present invention, the two groups of oil holes are axially symmetrically arranged on two axial sections of the rotor shaft and have different numbers. In the circumferential angle of the rotor shaft, the angle difference between any adjacent oil holes in the two groups of oil holes is equal.

[0016] The beneficial effects of the present invention are as follows: by opening an oil circuit in the motor rotor structure, cooling oil enters the iron core group inside the motor rotor for cooling, thereby enhancing the cooling effect on the motor rotor, and the cooling oil flows in the symmetrical oil circuit of the motor rotor structure, making the cooling effect more uniform. At the same time, by adjusting the number of oil circuit outlets of the motor rotor structure, the flow of cooling oil to the stator windings at both ends of the rotor is balanced.

[0017] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawings are incorporated into and constitute a part of the specification, illustrate embodiments consistent with the present invention, and together with the specification, are used to explain the principles of the present invention. Obviously, the drawings described below are only some embodiments of the present invention, and it is clear that a person skilled in the art can derive other drawings based on these drawings without inventive effort. In the drawings:

[0019] FIG1 is a schematic diagram of the motor rotor structure of the present invention;

[0020] FIG2 is a schematic diagram of the oil circuit structure of various parts of the motor rotor of the present invention;

[0021] FIG3 is a schematic structural diagram of the internal oil circuit of the motor rotor of the present invention;

[0022] FIG4 is a schematic structural diagram of the motor rotor structure of the present invention in an expanded oil circuit state;

[0023] Figure 5 (a) and (b) are schematic diagrams of the motor rotor structure of the present invention in the expanded state with different numbers of oil circuit groups;

[0024] Figure 6 (a), (b), and (c) are schematic structural diagrams of the motor rotor structure of the present invention in the expanded state when the oil outlet direction is changed;

[0025] FIG7 is a schematic structural diagram of the motor rotor structure of the present invention in an expanded state when the number of rotor shaft oil holes is changed.

[0026] In the figure: 1. Rotor shaft; 10. Inner hole; 11. Oil hole; 2. Balance plate; 21. Inlet oil groove; 22. Outlet oil groove; 23. Return oil groove; 3. Core assembly; 30. Core unit; 31. Oil channel. DETAILED DESCRIPTION

[0027] The following describes the embodiments of the present invention through specific examples. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following examples and the features in the examples can be combined with each other unless they conflict. It should also be understood that the terms used in the examples of the present invention are for the purpose of describing specific embodiments, not for the purpose of limiting the scope of protection of the present invention. The test methods for which specific conditions are not specified in the following examples are generally carried out under conventional conditions or under the conditions recommended by the manufacturers.

[0028] Please refer to Figures 1 to 7. It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention. Therefore, they have no technical significance. Any modification of the structure, change in the proportional relationship or adjustment of the size should still fall within the scope of the technical content disclosed by the present invention without affecting the efficacy and purpose that can be achieved by the present invention. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of description and are not used to limit the scope of the implementation of the present invention. Changes or adjustments in their relative relationships should also be regarded as the scope of the implementation of the present invention without substantially changing the technical content.

[0029] Please refer to Figures 1 to 6. The present invention provides an oil cooling system for a motor rotor, comprising a rotor shaft 1, a balancing disc 2, and an iron core group 3. An inner hole 10 is formed at one end of the rotor shaft 1, and two groups of oil holes 11 are formed on the side wall of the inner hole 10; the two balancing discs 2 are respectively connected to the side walls of the rotor shaft 1 where the two groups of oil holes 11 are formed, and an inlet oil groove 21 communicating with the oil holes 11 and an outlet oil groove 22 passing through the balancing discs 2 are formed on the balancing discs 2; the iron core group 3 is arranged around the circumferential outer side of the rotor shaft 1 and is located between the two balancing discs 2. The two ends of the iron core group 3 are respectively connected to the two balancing discs 2. Several oil passages 31 are provided in the inner portion of the core assembly 30. The oil passages 31 connect the inlet oil grooves 21 and outlet oil grooves 22 of the two balancing discs 2 at both ends of the core assembly 30. Cooling oil entering the inner hole 10 flows along the oil hole 11 of the rotor shaft 1 into the inlet oil groove 21 of the balancing disc 2, then passes through the inlet oil groove 21 into the oil passages 31 of the core assembly 3, and finally flows out through the outlet oil groove 22 along the oil passages 31. Adjacent oil passages 31 are connected at the same end to the inlet oil groove 21 and outlet oil groove 22, or to the two inlet oil grooves 21 or the two outlet oil grooves 22, respectively. This allows cooling oil to flow in both opposite and same directions in adjacent oil passages 31.

[0030] Furthermore, on a single balancing disk 2 at one end of the core group 3 , the same number of inlet oil grooves 21 and outlet oil grooves 22 are alternately arranged, and the sum of the number of the inlet oil grooves 21 and the outlet oil grooves 22 is equal to the number of the core monomers 30 .

[0031] In this embodiment, the motor rotor's cooling oil circuit is disposed within the motor's rotor shaft 1, the left and right balancing disks 2, and the motor rotor's iron core assembly 3. The iron core units 30 of the iron core assembly 3 are embedded with magnets and may be designed with four pairs of eight poles. As shown in Figure 2, four inlet oil grooves 21 are formed on the inner sides of the left and right balancing disks 2 (the sides contacting the iron core units 30). These inlet oil grooves 21 cooperate with the iron core units 30 to form a closed oil circuit for the balancing disk 2. The oil inlet of the inlet oil grooves 21 is aligned with the oil hole 11 of the rotor shaft 1, and the outlet of the inlet oil grooves 21 is aligned with the oil channel 31 on the iron core units 30. This ensures that after the cooling oil flows out of the oil hole 11 of the rotor shaft 1, it will flow into the interior of the rotor's iron core units 30 through the inlet oil grooves 21 on the balancing disk 2.

[0032] As shown in Figure 2, the core unit 30 has two sets of oil passages 31 of different shapes, located near the center of the core assembly 3, spaced evenly and symmetrically around the circumference. As shown in Figures 3 and 4, cooling oil flows from the inlet oil grooves 21 of the balancing discs 2 on both sides and into a set of oil holes 11 in the core assembly 3. Oil flowing in from the left side flows out from the right side, and vice versa. This alternating arrangement of oil passages 31 within the core unit 30 cools the magnets embedded in the core assembly 3.

[0033] It is worth mentioning that, in adjacent oil channels 31, the cooling oil is made to flow in opposite directions, so that the same number of inlet oil grooves 21 and outlet oil grooves 22 can be formed on the balancing disk 2 at both ends of the core group 3; in adjacent oil channels 31, the cooling oil is made to flow in the same direction, so that different numbers of inlet oil grooves 21 and outlet oil grooves 22 can be formed on the balancing disk 2 at both ends of the core group 3, and then inlet oil grooves 21 and outlet oil grooves 22 with different cross-sectional areas are formed on the balancing disk 2 at both ends of the core group 3, so as to adjust the flow parameters of the cooling oil in the balancing disk 2 at both ends accordingly to adapt to the working conditions.

[0034] It should be noted that the magnetic pole order of the core units 30 in the core assembly 3 is not limited; that is, the arrangement of N, S...N, S can be replaced with S, N...S, N. Furthermore, a skewed pole design is not implemented in the core assembly 3. However, this solution does not impose this limitation and may include corresponding designs, which will not be discussed here. The cross-sectional shapes of the oil holes 11, oil grooves, and oil passages 31 on the rotor shaft 1, balancing disk 2, and core units 30 are not limited and can be any other shape that satisfies the requirements for forming a flow path for the cooling oil. The shape and structure of the oil passages can also be adjusted to achieve better cooling performance.

[0035] Optionally, the locations of the first and second sets of oil passages 31 on the core unit 30 are not limited and may be located anywhere, including but not limited to within the large magnetic steel slots, within the small magnetic steel slots, near the magnetic steel slots, etc. Referring to FIG. 5 , a third set of oil passages 31 may be added to the core unit 30 , or only one set of oil passages 31 may be provided. The shape and location of the oil passages 31 also apply as described above.

[0036] Similarly, in addition to the four pairs of eight-pole core groups 3, this embodiment is also applicable to three pairs of six-pole rotors. The number of oil holes 11, oil grooves, and oil channels 31 in the oil circuits of the various components of the rotor can correspond to the number of rotor poles. Furthermore, in addition to permanent magnet synchronous motors, the cooling oil circuits of this embodiment are also applicable to asynchronous motors or electromagnetically excited motors.

[0037] Referring to FIG. 2 , in one embodiment, two groups of oil holes 11 are evenly arranged on the sidewalls of the inner bore 10 of the rotor shaft 1 , and are of equal number. The number of oil holes 11 is equal to the number of core units 30 in the core assembly 3 . In terms of the circumferential angle of the rotor shaft 1 , the angular difference between any adjacent oil holes 11 in the two groups of oil holes 11 is equal.

[0038] In this embodiment, cooling oil flows from the end of the rotor shaft 1 into the inner bore 10 of the rotor shaft 1. The rotor shaft 1 has oil holes 11 on two sections that mate with the left and right balancing discs 2. As shown in Figure 2, each section has four symmetrical oil holes 11. The angle between each oil hole 11 is 90°, and the two groups of oil holes 11 on the two sections have an angular difference of 45°. After entering the inner bore 10 of the rotor shaft 1, the cooling oil flows through the two groups of oil holes 11 into the inlet oil groove 21 of the balancing disc 2. By symmetrically distributing the oil holes 11 on the rotor shaft 1, the cooling oil, after entering the inlet oil groove 21 of the balancing disc 2, is evenly distributed along the left and right balancing discs 2 at both ends of the core assembly 3 and into each core unit 30.

[0039] Please refer to Figures 4 and 5. In one embodiment, at least one oil channel 31 is provided in the core unit 30, and the plurality of oil channels 31 are symmetrical about the circumference of the core assembly 3. That is, in the accompanying drawings, the oil channel 31 marked in the core unit 30 can indicate that the core unit 30 has only one oil channel marked as indicated by the oil channel 31, or multiple oil channels marked as indicated by the oil channel 31, without limitation. Similarly, it can be understood that the oil channel in the core unit 30 can consist of one oil channel 31 or multiple oil channels 31, with no limitation on the number. However, the overall circumferential symmetry must be maintained to achieve balanced cooling and maintain the stability of the rotor structure during operation.

[0040] Referring to Figures 4 and 5 , in one embodiment, when the core unit 30 has an odd number of oil passages 31, the inlet oil groove 21 and the outlet oil groove 22 are located at opposite ends of the core unit 30. When the core unit 30 has an even number of oil passages 31, the inlet oil groove 21 and the outlet oil groove 22 are located at the same end of the core unit 30. When the number of oil passages 31 in the core unit 30 is greater than one, a return oil groove 23 is further defined in the balancing plate 2 to connect adjacent oil passages 31 in the core unit 30.

[0041] In this embodiment, when multiple oil passages 31 are defined in the core unit 30, to ensure sufficient cooling oil flow through the rotor structure's oil passages, the cooling oil is caused to circulate back and forth along the oil passages between the core unit 30 and the balancing disc 2. As shown in Figures 2, 3, and 4, after flowing out of the first set of oil passages 31 in the core unit 30, the cooling oil flows into another oil passage formed by the balancing disc 2 and the core unit 30. This oil passage is formed by the oil return groove 23 on the balancing disc 2 and the core unit 30. The inlet of the oil return groove 23 is aligned with the first set of oil passages 31 in the core unit 30, and the outlet of the oil return groove 23 is aligned with the inlet of the second set of oil passages 31 in the core unit 30. After entering the second set of oil passages 31, the cooling oil enters from one side of the core unit 30 and exits from the other side, flowing symmetrically in opposite directions. (The cooling oil flows in opposite directions in the oil passages 31 of adjacent core units 30 and in adjacent oil passages 31 of core units 30, respectively.) This provides more uniform cooling along the length of the motor rotor. Finally, the cooling oil exits the second set of oil passages 31 of the core unit 30 and exits the rotor through the outlet oil grooves 22 of the left and right balance discs 2.

[0042] Furthermore, the end of the outlet oil groove 22 facing away from the core group 3 faces the stator end winding of the motor, so that after the cooling oil in the rotor structure is thrown out, it will spray and cool the inner side of the stator end winding, maintaining the cooling effect on the motor structure.

[0043] Referring to FIG. 6 , in one embodiment, in the core assembly 3 , the balancing discs 2 at both ends of at least one pair of axially symmetrical core units 30 are configured such that the inlet oil groove 21 and the outlet oil groove 22 are located at the same end of the core unit 30. On the balancing disc 2 at one end of the core unit 30 , the outlet oil groove 22 is closed at the end facing away from the core unit 30 and communicates with the inlet oil groove 21 . On the balancing disc 2 at the other end of the core unit 30 , the return oil groove 23 is provided with an outlet oil groove 22 . This allows for varying the number of outlet oil grooves 22 at both ends of the core assembly 3 .

[0044] Furthermore, in the core group 3, on the balancing disk 2 at both ends of at least one pair of axially symmetrical core monomers 30, when the inlet oil groove 21 and the outlet oil groove 22 are respectively located at the two ends of the core monomer 30; on the balancing disk 2 located at one end of the core monomer 30, the outlet oil groove 22 is closed at the end facing away from the core monomer 30 and is connected to the circuit oil groove 23; on the balancing disk 2 located at the other end of the core monomer 30, the outlet oil groove 22 is opened on the balancing disk 2, and the circuit oil groove 23 is connected to the outlet oil groove 22 or the inlet oil groove 21; so as to change the number of outlet oil grooves 22 at both ends of the core group 3.

[0045] Another important function of the cooling oil in the motor rotor oil circuit is to spray cool the inner side of the stator end windings after being spun out. However, because the cooling oil enters the inner bore 10 of the rotor shaft 1 asymmetrically, this can result in uneven distribution of oil between the two sets of oil holes 11 on the rotor shaft 1, leading to uneven oil flow to the stator end windings. To address this issue, an axially asymmetric oil passage 31 can be designed.

[0046] As shown in Figure 6 , in this embodiment, the oil circuit design of the balancing disc 2 connects the oil passages 31 on the core cells 30 in parallel. The oil circuit structure of the connected balancing disc 2 is adjusted in a pair of axially symmetrical core cells 30 within the core assembly 3. For example, the second and sixth core cells 30 from left to right in Figure 6 correspond to the connected balancing disc 2 oil circuits. For balancing discs 2 with the inlet and outlet oil grooves 21 and 22 located on the same side of the core cells 30, the outlet oil groove 22 of the balancing disc 2 can be sealed and connected to the inlet oil groove 21. The outlet oil groove 22 of the core cell 30 can then be opened in the return oil groove 23 at the other end.

[0047] Similarly, according to the different numbers of oil channels 31 in the core monomer 30, when the inlet oil groove 21 and the outlet oil groove 22 on the balancing plate 2 connected to the core monomer 30 are located at different ends, the structure of the outlet oil groove 22 in the balancing plate 2 is adjusted accordingly and connected to the circuit oil groove 23. Correspondingly, the outlet oil groove 22 is reopened at the other end, and the circuit oil groove 23 on the other end can be selectively connected to the outlet oil groove 22 or the inlet oil groove 21.

[0048] Regarding the different oil passage structures of the oil passages 31 connecting the core units 30 in the balancing disk 2, the oil passage structure in the balancing disk 2 is adjusted in the aforementioned manner, connecting two oil passages 31 in the core units 30 in parallel. This changes the final outflow direction of the cooling oil in the core units 30, thereby achieving the conditions for varying the amount of oil sprayed on the left and right sides of the rotor. Referring to the four-pair octapole core assembly 3 in Figure 6, the number of oil outlets at both ends can be adjusted from 4:4 to 6:2 (or 2:6). The corresponding number of oil outlets in the motor rotor with three-pair hexapole structures can be adjusted from 3:3 to 4:2 (or 2:4). By adjusting the number of outlet oil grooves 22 on the balancing disk 2 at both ends of the core assembly 3, the ratio of the cooling oil flow in the final outflow direction is changed, thereby balancing the difference in the amount of cooling oil entering the two sets of oil holes 11 from the inner bore 10 of the rotor shaft 1, maintaining a balanced amount of oil sprayed on the stator end windings at both ends of the rotor.

[0049] Referring to FIG. 7 , in one embodiment, two groups of oil holes 11 are axially symmetrically arranged on two axial cross-sections of the rotor shaft 1 , and the number of the two groups of oil holes 11 is unequal. In the circumferential angle of the rotor shaft 1 , the angular difference between any adjacent oil holes 11 in the two groups of oil holes 11 is equal.

[0050] It should be noted that the method of varying the cooling oil flow rate of the balancing disks 2 at both ends of the core assembly 3 by connecting two oil passages 31 in parallel in the core unit 30 in the aforementioned embodiment can also be achieved by adjusting the number of oil holes 11 on the rotor shaft 1. As shown in FIG7 , the second and sixth embodiments, for example, wherein two sets of oil passages 31 are provided in the core unit 30, can be achieved by varying the ratio of the number of oil holes 11 provided in the two sets of oil holes 11 on the rotor shaft 1. This allows the cooling oil entering the inner bore 10 from one end of the rotor shaft 1 to travel different distances through the inner bore 10 and exit through the two sets of oil holes 11 on the rotor shaft 1, reducing the difference in oil volume between the two sets of oil holes 11. This maintains a balanced amount of cooling oil ultimately sprayed from the outlet oil grooves 22 of the balancing disks 2 at both ends. Similarly, the scenarios with one or three sets of oil passages are similar. It is sufficient that the other requirements of the main scheme are met, which will not be elaborated upon here.

[0051] In summary, the present invention provides an oil-cooling system for a motor rotor, which allows the cooling oil to enter the iron core group 3 inside the motor rotor for cooling by opening an oil circuit in the motor rotor structure, thereby enhancing the cooling effect on the motor rotor, and the cooling oil flows in the symmetrical oil circuit of the motor rotor structure, making the cooling effect more uniform. At the same time, by adjusting the number of oil circuit outlets of the motor rotor structure, the flow of cooling oil to the stator windings at both ends of the rotor is balanced.

[0052] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the present invention. Anyone skilled in the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by one of ordinary skill in the art without departing from the spirit and technical principles disclosed herein are intended to be covered by the claims of the present invention.

Claims

1. A motor rotor oil cooling system, characterized in that: include: A rotor shaft (1), wherein an inner hole (10) is formed at one end of the rotor shaft (1), and two groups of penetrating oil holes (11) are formed on the side wall of the inner hole (10); A balancing disc (2), wherein the two balancing discs (2) are respectively connected to the side walls of the rotor shaft (1) on which the two groups of oil holes (11) are opened, and the balancing disc (2) is provided with an inlet oil groove (21) connected to the oil holes (11) and an outlet oil groove (22) penetrating the balancing disc (2); An iron core group (3), the iron core group (3) being arranged around the outer side of the rotor shaft (1) in the circumferential direction and between the two balancing disks (2), the iron core group (3) being provided with a plurality of oil passages (31), the oil passages (31) being connected to the inlet oil grooves (21) and the outlet oil grooves (22) of the two balancing disks (2) at both ends; Wherein, the same end of the adjacent oil passages (31) is respectively connected to the inlet oil groove (21) and the outlet oil groove (22), or is respectively connected to the two inlet oil grooves (21) or the two outlet oil grooves (22).

2. The cooling system according to claim 1, characterized in that: The two groups of oil holes (11) are evenly arranged on the side wall of the inner hole (10) of the rotor shaft (1) and are equal in number. The number of the oil holes (11) is equal to the number of the iron core monomers (30) in the iron core group (3); and at a circumferential angle of the rotor shaft (1), the angle difference between any adjacent oil holes (11) in the two groups of oil holes (11) is equal.

3. The cooling system according to claim 1, characterized in that: On the single balancing disk (2) at one end of the core group (3), the same number of inlet oil grooves (21) and outlet oil grooves (22) are arranged alternately, and the sum of the number of the inlet oil grooves (21) and the outlet oil grooves (22) is equal to the number of the core monomers (30).

4. The cooling system according to claim 3, characterized in that: At least one oil passage (31) is provided in the iron core unit (30), and a plurality of the oil passages (31) are symmetrical about the circumference of the iron core group (3).

5. The cooling system according to claim 4, characterized in that: When the number of the oil passages (31) of the iron core monomer (30) is an odd number, the inlet oil groove (21) and the outlet oil groove (22) are respectively located at two ends of the iron core monomer (30); When the number of the oil passages (31) of the iron core unit (30) is an even number, the inlet oil groove (21) and the outlet oil groove (22) are located at the same end of the iron core unit (30).

6. The cooling system according to claim 5, characterized in that: When the number of the oil passages (31) of the core monomer (30) is greater than one, a return oil groove (23) is further provided on the balancing plate (2), and the return oil groove (23) is connected to the adjacent oil passages (31) of the core monomer (30).

7. The cooling system according to claim 1, characterized in that: One end of the outlet oil groove (22) facing away from the iron core group (3) faces the stator end winding of the motor.

8. The cooling system according to claim 6, characterized in that In the core group (3), on the balancing disc (2) at both ends of at least one pair of axially symmetrical core monomers (30), when the inlet oil groove (21) and the outlet oil groove (22) are located at the same end of the core monomer (30); on the balancing disc (2) at one end of the core monomer (30), the end of the outlet oil groove (22) facing away from the core monomer (30) is closed and connected to the inlet oil groove (21); on the balancing disc (2) at the other end of the core monomer (30), the outlet oil groove (22) is opened on the return oil groove (23); so as to change the number of the outlet oil grooves (22) at both ends of the core group (3).

9. The cooling system according to claim 6, characterized in that: In the core group (3), on the balancing disc (2) at both ends of at least one pair of axially symmetrical core monomers (30), when the inlet oil groove (21) and the outlet oil groove (22) are respectively located at the two ends of the core monomer (30); on the balancing disc (2) located at one end of the core monomer (30), the end of the outlet oil groove (22) facing away from the core monomer (30) is closed and connected to the return oil groove (23); on the balancing disc (2) located at the other end of the core monomer (30), the outlet oil groove (22) is opened on the balancing disc (2), and the return oil groove (23) is connected to the outlet oil groove (22) or the inlet oil groove (21); so as to change the number of the outlet oil grooves (22) at both ends of the core group (3).

10. The cooling system according to claim 1, characterized in that The two groups of oil holes (11) are axially symmetrically arranged on two axial cross sections of the rotor shaft (1) and have different numbers. At a circumferential angle of the rotor shaft (1), the angle difference between any adjacent oil holes (11) in the two groups of oil holes (11) is equal.

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