Oil circuit cooling structure of a permanent magnet synchronous motor

Abstract

The utility model discloses an oil circuit cooling structure of a permanent magnet synchronous motor, comprising: an oil filling assembly, the oil filling assembly comprises a rotating shaft, one end of the rotating shaft is formed with an oil filling port; a cooling assembly, the internal shaft side of the cooling assembly is provided with a penetrating rotor oil passage, the rotor oil passage comprises a staggered pole rotor oil passage; an oil delivery assembly, the two end surfaces of the oil delivery assembly are formed with an oil inlet passage and an oil return passage, one end of the oil inlet passage is connected with the oil filling port, and one end of the oil return passage is connected with the outside of the cooling assembly; the rotor oil passage, the oil inlet passage and the oil return passage can form a cooling oil circuit arranged on the inner circumference of the cooling assembly. The utility model arranges the oil inlet passage and the oil return passage, so that the flow direction of the cooling oil in the rotor core is divided into from left to right, from right to left or both from left to right; by arranging the staggered pole rotor oil passage, the contact area between the cooling oil and the rotor core is increased, the efficiency of absorbing the heat of the magnetic steel is improved, and the service life of the motor is increased.

Description

Technical Field

[0001] The utility model relates to the technical field of motor rotors, in particular to an oil circuit cooling structure of a permanent magnet synchronous motor. Background Art

[0002] The core component of new energy vehicles is the drive motor, which is a permanent magnet synchronous motor. The magnetic force of the magnets inside the permanent magnet synchronous motor is greatly affected by the ambient temperature. When the heat dissipation effect of the drive motor is not good, the power and torque of the motor will be reduced at the least, and the magnets will be demagnetized at the worst, which will have a permanent reverse effect on the power of the vehicle.

[0003] In the prior art, the rotor's deweighting holes are usually used as cooling oil circuits, but the distance between the cooling oil circuit and the magnetic steel is too large, and the heat dissipation effect on the magnetic steel is poor; in addition, the cooling oil circuit is a straight hollow pipe, and the cooling oil stays in it for too short a time, and the efficiency of absorbing the heat of the magnetic steel is low. In short, the existing method of cooling the motor magnetic steel has a poor cooling effect and reduces the service life of the motor. Utility Model Content

[0004] In order to solve the problem of poor heat dissipation effect of magnetic steel inside the motor, the utility model provides an oil circuit cooling structure of a permanent magnet synchronous motor. The specific technical solution is as follows:

[0005] An oil circuit cooling structure for a permanent magnet synchronous motor comprises: an oil filling assembly, the oil filling assembly comprises a rotating shaft, one end of the rotating shaft is formed with an oil filling port; a cooling assembly arranged on the circumferential side of the rotating shaft, the internal shaft side of the cooling assembly is provided with at least one penetrating rotor oil passage, the rotor oil passage comprises at least one staggered pole rotor oil passage; an oil delivery assembly arranged at both ends of the cooling assembly, the two end surfaces of the oil delivery assembly are formed with an oil inlet passage and an oil return passage, one end of the oil inlet passage is connected to the oil filling port, and one end of the oil return passage is connected to the outside of the cooling assembly; the rotor oil passage, the oil inlet passage and the oil return passage can form a cooling oil circuit arranged on the inner circumferential side of the cooling assembly.

[0006] Furthermore, the cooling assembly also includes at least two sections of a rotor core arranged on the circumferential side of the rotating shaft, and magnetic steel is evenly distributed inside the rotor core along the circumferential side of the rotating shaft. The axis of the magnetic steel, the axis of the rotor core and the axis of the rotor oil channel are all parallel and equal. The rotor oil channel includes a staggered pole rotor oil channel, and the number of sections of the staggered pole rotor oil channel is the same as the number of sections of the rotor core. At least a part of the projections of each section of the staggered pole rotor oil channel on the end face of the rotor core do not overlap. The rotor oil channel also includes a through rotor oil channel, and the number of sections of the through rotor oil channel is the same as the number of sections of the rotor core. The projections of each section of the through rotor oil channel on the end face of the rotor core overlap, and the through rotor oil channel is connected to the staggered pole rotor oil channel through an oil inlet channel.

[0007] Furthermore, the oil injection assembly also includes oil holes arranged on the circumferential side of the rotating shaft, which oil holes correspond one-to-one to the oil inlet passages, the oil inlet passages are connected to one end of at least one staggered pole rotor oil passage, and the oil return passages are connected to the other end of at least one staggered pole rotor oil passage.

[0008] Preferably, the oil filling assembly also includes: a hollow central oil passage with a closed end arranged at the axial position of the rotating shaft, the opening side of the central oil passage is close to the oil filling port; and an oil hole arranged on the circumferential side of the rotating shaft, the oil hole connecting the central oil passage with the oil inlet passage, the oil hole including at least one first oil hole, the first oil hole being arranged on the circumferential side of the rotating shaft and close to one end of the cooling assembly, the first oil hole connecting the central oil passage and the oil inlet passage, the oil hole also including at least one second oil hole, the second oil hole being arranged on the circumferential side of the rotating shaft and close to the other end of the cooling assembly, the second oil hole connecting the central oil passage and the oil inlet passage, and the distance between the second oil hole and the first oil hole is equal to the length of the rotor oil passage.

[0009] Preferably, the oil delivery assembly further comprises: two end covers arranged at both ends of the cooling assembly, the oil inlet passage and the oil return passage are formed on a side of the end cover close to the cooling assembly, and the end of the rotating shaft formed with the oil filling port is defined as the left end, characterized in that: the end cover comprises a first end cover arranged at the left end of the cooling assembly and a second end cover arranged at the right end of the cooling assembly; the oil inlet passage comprises a first oil inlet passage arranged on the inner side of the first end cover and a second oil inlet passage arranged on the inner side of the second end cover; the oil return passage comprises a first oil return passage arranged on the inner side of the first end cover and a second oil return passage arranged on the inner side of the second end cover ; and the rotor oil channel includes a first rotor oil channel connected to the first oil inlet channel at the left end and a second rotor oil channel connected to the second oil inlet channel at the right end, the cooling oil circuit includes a first cooling oil circuit, the cooling oil in the first cooling oil circuit flows out from the first oil hole, flows through the first oil inlet channel, flows through the first rotor oil channel, and then flows out of the cooling component from the other end of the second return oil channel, the cooling oil circuit includes a second cooling oil circuit, the cooling oil in the second cooling oil circuit flows out from the second oil hole, flows through the second oil inlet channel, flows through the second rotor oil channel, and then flows out of the cooling component from the other end of the first return oil channel.

[0010] It can be seen from the above technical solution that the utility model has the following beneficial effects:

[0011] The utility model evenly distributes magnetic steel on the circumferential side of the rotor core and sets rotor oil channels on the circumferential side of the magnetic steel, so that all cooling oil flowing through the rotor oil channels are at the same distance from the magnetic steel, thereby ensuring uniform heat dissipation of all magnetic steels inside the motor. Secondly, by setting oil inlet channels and oil return channels, the flow direction of the cooling oil in the rotor core is divided into from left to right, from right to left, or from left to right, so that the cooling oil can evenly absorb the heat of the magnetic steel; furthermore, by setting the rotor oil channels as staggered-pole rotor oil channels, the flow time of the cooling oil in the rotor core is increased, the efficiency of absorbing the heat of the magnetic steel is improved, and the service life of the motor is thereby increased. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a cross-sectional view of embodiment 1 of the utility model Figure 1 ;

[0013] Figure 2 This is a cross-sectional view of embodiment 1 of the utility model Figure 2 ;

[0014] Figure 3 This is an end view of the cooling assembly of Example 1 of the utility model;

[0015] Figure 4 The inner end surface of the end cover of Example 1 of the utility model;

[0016] Figure 5 This is a schematic diagram of the oil passage structure of the staggered-pole rotor of the utility model.

[0017] In the figure: 1. oil filling assembly; 2. cooling assembly; 3. oil delivery assembly; 4. cooling oil circuit; 11. rotating shaft; 12. central oil channel; 13. oil filling port; 14. oil hole; 141. first oil hole; 142. second oil hole; 21. rotor core; 22. magnetic steel; 23. rotor oil channel; 231. through rotor oil channel; 232. staggered pole rotor oil channel; 233. first rotor oil channel; 234. second rotor oil channel; 31. end cover; 32. oil inlet channel; 33. oil return channel; 311. first end cover; 312. second end cover; 321. first oil inlet channel; 322. second oil inlet channel; 331. first oil return channel; 332. second oil return channel; 41. first cooling oil circuit; 42. second cooling oil circuit. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0019] In the description of the embodiments of the present invention, it should be noted that the terms "inside", "outside", "upper", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the utility model product is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0020] like Figure 1As shown, the first embodiment of the utility model includes an oil injection component 1, which is connected to a cooling component 2 by an interference fit, and the two end surfaces of the cooling component 2 are connected to oil delivery components 3, and a cooling oil circuit 4 is formed inside the oil delivery component 3 and the cooling component 2. The cooling oil circuit 4 can take away the heat inside the cooling component 2 through the cooling oil flowing inside, thereby ensuring the working efficiency and service life of the permanent magnet motor.

[0021] like Figure 1 to Figure 2 As shown, the oil filling assembly 1 includes a rotating shaft 11 of a permanent magnet motor, which is a stepped shaft. A central oil passage 12 is formed at the axial position of the rotating shaft 11. The left end of the central oil passage 12 is opened to form an oil filling port 13. The right end of the central oil passage 12 is closed, and an oil hole 14 is formed on the peripheral side of the central oil passage 12.

[0022] Specifically, in the present embodiment, the oil hole 14 includes a first oil hole 141 and a second oil hole 142, and in other embodiments, the oil hole 14 may only include the first oil hole 141 or the second oil hole 142, and four first and second oil holes are provided, and the four first and second oil holes are respectively evenly distributed on the periphery of the central oil passage 12, and the distance between the first and second oil holes is equal to the length of the cooling component 2, so that cooling oil is injected from the outside through the oil filling port 13, and can be gathered in the central oil passage 12, and injected into the oil delivery component 3 at both ends of the cooling component 2 through the first and second oil holes, and then injected into the cooling oil circuit 4 to cool the cooling component 2.

[0023] Secondly, the cooling assembly 2 includes a rotor core 21 fixed to the circumferential side of the rotating shaft 11 by interference fit, and eight groups of magnets 22 arranged along the axial direction of the rotating shaft 11 are fixed inside the rotor core 21. The rotor core 21 is divided into six sections, and each section is evenly staggered at a certain angle in the circumferential direction, so that the magnets 22 inside the rotor core 21 are arranged obliquely, which can change the distribution of magnetic lines of force and thereby reduce the imbalance of electromagnetic force when the motor is running, thereby reducing the vibration and noise generated thereby.

[0024] Combination Figure 3 As shown, eight groups of rotor oil passages 23 are uniformly distributed inside the rotor core 21, and eight groups of magnets 22 are arranged around the rotor oil passages 23. The rotor oil passages 23 include through-rotor oil passages 231 and staggered-pole rotor oil passages 232. The magnets 22 are divided into small magnets 22 and large magnets 22, wherein the symmetry lines of each group of large and small magnets 22 pass through the axis of the rotor core 21, and pass through the openings of the through-rotor oil passages 231 and staggered-pole rotor oil passages 232, respectively. The length direction of the through-rotor oil passages 231 is parallel to the length direction of the rotating shaft 11, and the projections of each section on the end face of the rotor core 21 overlap, so that the cooling oil in the through-rotor oil passages 231 can flow unimpeded, thereby increasing the flow rate of the cooling oil.

[0025] Secondly, combined Figure 5As shown, the projections of each section of the staggered-pole rotor oil channel 232 on the end surface of the rotor core 21 do not overlap in part, which increases the flow obstacle of the cooling oil therein, reduces the flow rate of the cooling oil therein, increases the flow time of the cooling oil therein, and further increases the time for the cooling oil to absorb the heat generated by the magnetic steel 22, thereby improving the heat dissipation efficiency of the cooling component 2.

[0026] In other embodiments, the rotor oil passage 23 may only include the staggered-pole rotor oil passage 232 , which can greatly improve the heat dissipation efficiency of the cooling assembly 2 and extend the service life of the motor.

[0027] Secondly, the oil delivery assembly 3 includes an end cover 31 fixed to both end surfaces of the rotor core 21, and the end cover 31 is connected to the rotor core 21 by the shaft shoulder in the middle part of the rotating shaft 11 and the fixing block at the right end to prevent leakage of cooling oil at the connection between the oil delivery assembly 3 and the cooling assembly 2. The end cover 31 includes a first end cover 311 on the left end surface of the rotor core 21 and a second end cover 312 on the right end surface of the rotor core 21, wherein the first and second end covers 312 are formed with four groups of oil inlet passages 32 and four groups of oil return passages 33 on the inner end surfaces close to the rotor core 21.

[0028] Combination Figure 4 As shown, the oil inlet passage 32 is a Y-shaped oil passage, one end of which is connected to the oil hole 14, and the forked ends thereof are respectively connected to the through-rotor oil passage 231 and the staggered-pole rotor oil passage 232, so that the cooling oil enters the oil inlet passage 32 through the oil hole 14, and then enters the rotor oil passage 23; the oil return passage 33 is an eight-shaped oil passage, the narrow end of which is connected to the remaining four groups of through-rotor oil passages 231 and the staggered-pole rotor oil passages 232, and the wide end of which is connected to the peripheral side of the rotor core 21 and is connected to the cooler (not shown in the figure), so that the cooling oil enters the rotor oil passage 23 and then enters the oil return passage 33, and then flows out of the rotor core 21 into the interior of the motor, and then flows into the cooler through the oil circuit for cooling circulation, so that the cooling oil can be recycled.

[0029] In other embodiments, an oil inlet passage 32 is connected to a rotor oil passage 23. A rotor oil passage 23 may include only staggered-pole rotor oil passages 232 or through-rotor oil passages 231, or both. Increasing the number of staggered-pole rotor oil passages 232 can increase the contact area between the cooling oil and the rotor core 21, thereby improving the heat dissipation efficiency of the embodiment. Increasing the number of through-rotor oil passages 231 can increase the flow rate of the cooling oil, but will reduce the heat dissipation efficiency of the embodiment. The specific combination of the two quantities needs to be adjusted according to actual production requirements.

[0030] Secondly, the first end cover 311 forms a first oil inlet passage 321 and a first oil return passage 331, the second end cover 312 forms a second oil inlet passage 322 and a second oil return passage 332, the rotor oil passage 23 includes a first rotor oil passage 233 and a second rotor oil passage 234, the first and second rotor oil passages 234 are evenly distributed on the side of the rotating shaft 11, and the angles between them are 45 degrees.

[0031] In addition, the cooling oil circuit 4 includes a first cooling oil circuit 41 and a second cooling oil circuit 42. The cooling oil in the first cooling oil circuit 41 flows from the first end cover 311 to the second end cover 312, while the second cooling oil circuit 42 flows from the second end cover 312 to the first end cover 311, so that the cooling oil can more fully contact the magnetic steel 22, and more evenly reduce the temperature of the magnetic steel 22, thereby avoiding a large temperature difference in the magnetic steel 22 and causing a decrease in its magnetic properties.

[0032] The flow route of the cooling oil in the first cooling oil circuit 41 is: enter the central oil channel 12 from the oil filling port 13, then enter the first oil inlet channel 321 from the first oil hole 141, then flow from the first rotor oil channel 233 to the second oil return channel 332, and finally flow out of the rotor core 21 from the second oil return channel 332, wherein the heat of the magnetic steel 22 is absorbed when flowing through the first rotor oil channel 233.

[0033] The flow route of the cooling oil in the second cooling oil circuit 42 is: enter the central oil channel 12 from the oil filling port 13, then enter the second oil inlet channel 322 from the second oil hole 142, then flow from the second rotor oil channel 234 to the first return oil channel 331, and finally flow out of the rotor core 21 from the first return oil channel 331, wherein the heat of the magnetic steel 22 is absorbed when flowing through the second rotor oil channel 234.

[0034] In other embodiments, the cooling oil circuit 4 only includes the first cooling oil circuit 41 or the second cooling oil circuit 42, and the flow direction of the cooling oil is limited to flowing from the first end cover to the second end cover, or from the second end cover to the first end cover. The contact area between the cooling oil and the rotor core 21 is the same as that in the first embodiment, but the cooling oil flowing in a single direction absorbs the heat of the magnetic steel 22 in a single direction, so that the temperature difference between the two ends of the magnetic steel 22 may be too large, thereby weakening the magnetism of the magnetic steel 22 and reducing the power of the motor.

[0035] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

[0036] The technology, shape and structure parts not described in detail in the present invention are all known technologies.

Claims

1. An oil circuit cooling structure for a permanent magnet synchronous motor, characterized in that: include: An oil injection assembly (1), the oil injection assembly (1) comprising a rotating shaft (11), one end of the rotating shaft (11) being formed with an oil injection port (13); A cooling assembly (2) disposed on the circumferential side of the rotating shaft (11), wherein at least one penetrating rotor oil passage (23) is disposed on the internal shaft side of the cooling assembly (2), and the rotor oil passage (23) includes at least one staggered-pole rotor oil passage (232); An oil delivery assembly (3) disposed at both ends of the cooling assembly (2), wherein an oil inlet passage (32) and an oil return passage (33) are formed on both end surfaces of the oil delivery assembly (3), wherein one end of the oil inlet passage (32) is connected to the oil injection port (13), and one end of the oil return passage (33) is connected to the outside of the cooling assembly (2); The rotor oil passage (23), the oil inlet passage (32) and the oil return passage (33) can form a cooling oil circuit (4) arranged on the inner peripheral side of the cooling assembly (2).

2. The oil circuit cooling structure according to claim 1, characterized in that: The cooling assembly (2) further comprises at least two sections of a rotor core (21) arranged on the circumference of the rotating shaft (11); magnetic steel (22) is evenly distributed inside the rotor core (21) along the circumference of the rotating shaft; the axis of the magnetic steel (22), the axis of the rotor core (21) and the axis of the rotor oil passage (23) are all parallel and equal; the rotor oil passage (23) comprises a staggered-pole rotor oil passage (232); the number of sections of the staggered-pole rotor oil passage (232) is the same as the number of sections of the rotor core (21); and projections of the sections of the staggered-pole rotor oil passage (232) on the end surface of the rotor core (21) at least partially do not overlap.

3. The oil circuit cooling structure according to claim 2, characterized in that: The rotor oil passage (23) further comprises a through rotor oil passage (231), the number of sections of the through rotor oil passage (231) being the same as the number of sections of the rotor iron core (21), the projections of the sections of the through rotor oil passage (231) on the end surface of the rotor iron core (21) all coincide, and the through rotor oil passage (231) is connected to the staggered-pole rotor oil passage (232) via the oil inlet passage (32).

4. The oil circuit cooling structure according to claim 1, characterized in that: The oil injection assembly (1) further comprises an oil hole (14) arranged on the circumferential side of the rotating shaft (11), the oil hole (14) corresponding one-to-one to the oil inlet passage (32), the oil inlet passage (32) being connected to one end of at least one staggered-pole rotor oil passage (232), and the oil return passage (33) being connected to the other end of at least one staggered-pole rotor oil passage (232).

5. The oil circuit cooling structure according to claim 1, characterized in that: The oil injection assembly (1) further comprises: A hollow central oil passage (12) with a closed end disposed at an axial position of the rotating shaft (11), wherein the opening side of the central oil passage (12) is close to the oil filling port (13); and An oil hole (14) is arranged on the circumferential side of the rotating shaft (11), and the oil hole (14) communicates with the central oil passage (12) and the oil inlet passage (32).

6. The oil circuit cooling structure according to claim 5, characterized in that: The oil hole (14) comprises at least one first oil hole (141), which is arranged on the circumference of the rotating shaft (11) and close to one end of the cooling assembly (2), and the first oil hole (141) is connected to the central oil channel (12) and the oil inlet channel (32).

7. The oil circuit cooling structure according to claim 6, characterized in that: The oil hole (14) also includes at least one second oil hole (142), which is arranged on the circumference of the rotating shaft (11) and close to the other end of the cooling assembly (2), and the second oil hole (142) is connected to the central oil channel (12) and the oil inlet channel (32), and the distance between the second oil hole (142) and the first oil hole (141) is equal to the length of the rotor oil channel (23).

8. According to the oil circuit cooling structure of claim 7, the oil delivery component (3) further comprises: Two end covers (31) are arranged at both ends of the cooling assembly (2), the oil inlet passage (32) and the oil return passage (33) are formed on a side of the end cover (31) close to the cooling assembly (2), and the end of the rotating shaft (11) formed with the oil filling port (13) is defined as the left end, characterized in that: The end cover (31) comprises a first end cover (311) arranged at the left end of the cooling component (2) and a second end cover (312) arranged at the right end of the cooling component (2); The oil inlet passage (32) comprises a first oil inlet passage (321) arranged on the inner side of the first end cover (311) and a second oil inlet passage (322) arranged on the inner side of the second end cover (312); The oil return passage (33) comprises a first oil return passage (331) arranged on the inner side of the first end cover (311) and a second oil return passage (332) arranged on the inner side of the second end cover (312); and The rotor oil passage (23) comprises a first rotor oil passage (233) whose left end is connected to the first oil inlet passage (321) and a second rotor oil passage (234) whose right end is connected to the second oil inlet passage (322).

9. The oil circuit cooling structure according to claim 8, characterized in that: The cooling oil circuit (4) comprises a first cooling oil circuit (41), wherein the cooling oil in the first cooling oil circuit (41) flows out from the first oil hole (141), then flows through the first oil inlet passage (321), then flows through the first rotor oil passage (233), and then flows out of the cooling assembly (2) from the other end of the second oil return passage (332).

10. The oil circuit cooling structure according to claim 9, characterized in that: The cooling oil circuit (4) comprises a second cooling oil circuit (42), the cooling oil in the second cooling oil circuit (42) flows out from the second oil hole (142), then flows through the second oil inlet channel (322), then flows through the second rotor oil channel (234), and then flows out of the cooling assembly (2) from the other end of the first oil return channel (331).

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