Bidirectional oil-cooled motor stator heat dissipation structure

Abstract

The application belongs to the technical field of oil-cooled motors, and particularly relates to a bidirectional oil-cooled motor stator heat dissipation structure, which comprises a motor shell and a stator core installed in the motor shell; the outer circumferential surface of the stator core is in interference fit with the inner circumferential surface of the motor shell; the stator core is sequentially divided into a first oil outlet section, a second oil inlet section, a main body section, a first oil inlet section and a second oil outlet section along the axial direction from the first end portion to the second end portion; a plurality of oil path units are arranged in the stator core and are spaced apart in the circumferential direction, and each oil path unit comprises a first oil path and a second oil path; the first oil path extends from the end surface of the first end portion to the outer circumferential surface of the first oil inlet section along the axial direction; the second oil path extends from the end surface of the second end portion to the outer circumferential surface of the second oil inlet section along the axial direction; a conveying oil path is formed in the motor shell, an oil inlet of the conveying oil path is formed on the outer surface of the motor shell, one oil outlet of the conveying oil path is in communication with all the first oil inlets, and the other oil outlet is in communication with all the second oil inlets.

Description

Technical Field

[0001] This invention belongs to the field of oil-cooled motor technology, and specifically relates to a bidirectional oil-cooled motor stator heat dissipation structure. Background Technology

[0002] As competition intensifies in the new energy vehicle sector regarding energy consumption, cost, and spatial comfort, the trend towards lightweighting and miniaturization of electric drive systems is driving the development of drive motors towards higher power density and higher speeds. The continuous increase in motor power density and speed also leads to increased heat loss, while the trend towards miniaturization restricts heat dissipation space. The combined effect of these three factors presents a severe challenge to motor heat dissipation.

[0003] To address the increasingly severe heat dissipation challenges of electric motors, current mainstream motor cooling technologies typically employ oil cooling structures for the stator, using oil channels on the stator core to directly cool it through the flow of cooling oil. However, because the cooling oil gradually absorbs heat and heats up along its flow direction, the heat exchange effect in downstream areas is weakened. Furthermore, existing oil cooling structures for motor stators often use oil channels that transport cooling oil from the middle of the stator core to both ends or from one end to the other. This results in a unidirectional axial flow of cooling oil in existing stator oil cooling structures, leading to uneven cooling of the stator core. Summary of the Invention

[0004] To address the shortcomings of the prior art, the present invention provides a bidirectional oil-cooled motor stator heat dissipation structure, thereby solving the problem of uneven cooling of the stator core caused by the unidirectional flow direction of the cooling oil in the axial direction of the stator core in existing oil-cooled motor stators.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows: A bidirectional oil-cooled motor stator heat dissipation structure includes: a motor housing and a stator core installed inside the motor housing; the outer peripheral surface of the stator core is interference-fitted with the inner peripheral surface of the motor housing; The stator core is divided into a first oil outlet section, a second oil inlet section, a main body section, and a second oil outlet section along its axial direction from its first end to its second end. The stator core is provided with a plurality of oil passage units spaced apart along the circumference. Each oil passage unit includes a first oil passage and a second oil passage. The first oil passage and the second oil passage are arranged spaced apart along the circumference of the stator core. Both the first oil passage and the second oil passage extend axially on the stator core. The first oil outlet of the first oil passage extends to the end face of the first end, and the first oil inlet of the first oil passage extends to the outer peripheral surface of the first oil inlet section; The second oil outlet of the second oil passage extends to the end face of the second end, and the second oil inlet of the second oil passage extends to the outer peripheral surface of the second oil inlet section; The motor housing has an oil delivery passage with one oil inlet and two oil outlets. The oil inlet is located on the outer surface of the motor housing, and the two oil outlets are located on the inner circumferential surface of the motor housing. One of the oil outlets is connected to all the first oil inlets, and the other oil outlet is connected to all the second oil inlets.

[0006] By setting up each of the first oil passages and each of the second oil passages, the bidirectional oil-cooled motor stator heat dissipation structure provided by the present invention actually forms multiple oil passages (including each of the first oil passages and each of the second oil passages) arranged circumferentially on the stator core. Furthermore, any two adjacent oil passages can independently transport cooling oil in opposite directions along the axial direction of the stator core (i.e., the first oil passage transports cooling oil from the second end of the stator core to the first end, and then flows out from the end face of the first end; the second oil passage transports cooling oil from the first end of the stator core to the second end, and then flows out from the end face of the second end). By setting up bidirectional oil passages, the cooling uniformity of the stator core can be improved as much as possible, solving the technical problem of uneven cooling of the stator core due to the single axial flow direction of the cooling oil in the existing oil-cooled motor stator structure.

[0007] Furthermore, the first oil passage is divided into a plurality of sequentially connected first flow channels along the axial direction of the stator core, and the second oil passage is divided into a plurality of sequentially connected second flow channels along the axial direction of the stator core; each first flow channel and each second flow channel extends along the axial direction of the stator core. The minimum distance between any two adjacent first flow channels and the central axis of the stator core is different; the minimum distance between any two adjacent second flow channels and the central axis is also different.

[0008] Due to the trend towards lightweighting and miniaturization of electric drive systems, the design size of the oil flow channels in existing motor stator oil-cooled structures is typically small. This results in the cooling oil in existing stator oil-cooled structures generally flowing in a laminar state within the oil flow channels, with the boundary layer thickness gradually increasing along the flow direction, further exacerbating the problem of weakened heat exchange in the downstream region. However, by ensuring that the minimum distances between any two adjacent first flow channels and the central axis of the stator core are different, and the minimum distances between any two adjacent second flow channels and the central axis are also different, the bidirectional oil-cooled motor stator heat dissipation structure provided by this invention features first and second oil paths that are stepped flow channels along the cooling oil flow direction. The presence of this stepped structure creates turbulence, thereby disrupting or weakening the growth of the boundary layer, improving the problem of weakened heat exchange in the downstream region, and also increasing the heat exchange area. Improve the convective heat transfer effect of cooling oil in the oil flow channel.

[0009] Furthermore, the stator core is composed of multiple first stator laminations and multiple second stator laminations stacked together; The first stator lamination is divided into multiple first sector groups along the circumferential direction, and the first sector group is divided into a first sector portion and a second sector portion along the circumferential direction. A second sector portion is provided between any two adjacent first sector portions. The second stator lamination is divided into multiple second sector groups along the circumferential direction, and the second sector group is divided into third sector portions and fourth sector portions along the circumferential direction. A fourth sector portion is provided between any two adjacent third sector portions. The central angles of the first sector, the second sector, the third sector, and the fourth sector are equal; The first sector has a first oil passage, the second sector has a second oil passage, and the second sector group has a third oil passage; The first oil passage includes an oil groove formed on the outer arc surface of the first sector portion, the oil groove extending along the axial direction of the first sector portion and penetrating the first sector portion; The second oil passage includes a first oil hole formed on the side of the second sector portion, the first oil hole extending along the axial direction of the second sector portion and penetrating the second sector portion; The third oil passage includes a second oil hole formed on the side of the third sector, the second oil hole extending along the axial direction of the third sector and penetrating the third sector; The oil groove on the first sector portion is connected to the first oil hole on the second sector portion that overlaps and fits with the first sector portion; The first oil hole on the second sector and the second oil hole on the third sector that overlaps and fits with the second sector are connected; When the first sector and the fourth sector overlap and fit together, the fourth sector blocks the end of the oil groove on the first sector that faces the fourth sector. The first oil passage, the second oil passage, and the third oil passage are used to cooperate with each other to form each of the first oil passage and each of the second oil passage.

[0010] By dividing the first stator laminations into first sector portions and second sector portions, and dividing the second stator laminations into third sector portions and fourth sector portions, and by opening a first oil channel on the first sector portion, a second oil channel on the second sector portion, and a third oil channel on the second sector portion, the stator core can be formed by offset stacking the first and second stator laminations with the central angle of the sector portion (first sector portion, second sector portion, third sector portion, or fourth sector portion) as the unit. At the same time, the first oil channel and the second oil channel are formed on the stator core by overlapping and bonding between different sector portions.

[0011] Furthermore, an oil return port is provided on the front end and / or rear end of the motor housing.

[0012] There are various specific stacking schemes, including but not limited to: Option A: The first oil outlet section and the second oil outlet section are both composed of multiple stacked second stator laminations; the second oil inlet section, the main body section, and the first oil inlet section are all composed of multiple stacked first stator laminations.

[0013] Furthermore, the projections of each of the third sector portions on any second stator lamination in the first oil outlet section onto the radial section of the stator core, the projections of each of the second sector portions on any first stator lamination in the second oil inlet section onto the radial section, the projections of each of the first sector portions on any first stator lamination in the first oil inlet section onto the radial section, and the projections of each of the fourth sector portions on any second stator lamination in the second oil outlet section onto the radial section all coincide; Each of the oil troughs on the first oil inlet section is connected to one of the oil outlets, and each of the oil troughs on the second oil inlet section is connected to the other oil outlet.

[0014] Furthermore, the main body segment is sequentially divided into multiple main body sub-segments along its axial direction; Each of the aforementioned main body sub-segments is formed by stacking multiple first stator laminations; The projection of each first sector on any first stator lamination in any main body sub-segment onto the radial section coincides with the projection of each second sector on any first stator lamination in the adjacent main body sub-segment onto the radial section.

[0015] Furthermore, the projection of each second sector on the radial section of any first stator lamination in the main body sub-segment closest to the second oil inlet section coincides with the projection of each first sector on the radial section of any first stator lamination in the second oil inlet section. The projection of each second sector on the radial section of any first stator lamination in the main body sub-segment closest to the first oil inlet section coincides with the projection of each first sector on the radial section of any first stator lamination in the first oil inlet section.

[0016] Furthermore, the first minimum distance between the oil groove and the central axis of the stator core is greater than the second minimum distance between the first oil hole and the central axis; The second minimum distance value is greater than the third minimum distance value between the second oil hole and the central axis.

[0017] In the above scheme A, the projections of the third sector portions on any second stator lamination in the first oil outlet section onto the radial section of the stator core, the projections of the second sector portions on any first stator lamination in the second oil inlet section onto the radial section, the projections of the first sector portions on any first stator lamination in the first oil inlet section onto the radial section, and the projections of the fourth sector portions on any second stator lamination in the second oil outlet section all coincide (that is, the projections of the second sector portions on any first stator lamination in the first oil inlet section and the projections of the third sector portions on any second stator lamination in the second oil outlet section onto the radial section are all made coincident). (The projections all coincide); and make the second minimum distance value greater than the third minimum distance value; that is, a double-layer stepped flow channel is formed radially inward at the end of each first oil passage (that is, the flow channel of each first oil passage in the second oil inlet section and the first oil outlet section) and the end of each second oil passage (that is, the flow channel of each second oil passage in the first oil inlet section and the second oil outlet section); so that the cooling oil in each first oil passage can form a centripetal jet oil flow when it flows out of the end face of the first end, directly cooling the end of the stator winding outside the first end, and so that the cooling oil in each second oil passage can form a centripetal jet oil flow when it flows out of the end face of the second end, directly cooling the end of the stator winding outside the second end. Compared to existing oil-cooled motor stators, which typically require oil spray rings to be installed at both ends of the stator core to ensure the formation of centripetal oil jets, the bidirectional oil-cooled motor stator heat dissipation structure provided by the above-mentioned scheme A not only eliminates the need for oil spray rings, saving the installation space required by the oil spray rings and facilitating the miniaturization design of oil-cooled motors, but also saves on the process costs caused by the sealing process between the oil spray rings, motor housing, and stator core.

[0018] Option B, the third oil passage further includes a third oil hole formed on the side of the fourth sector, the third oil hole extending along the axial direction of the fourth sector and penetrating the fourth sector; The second oil hole on the third sector is connected to the third oil hole on the fourth sector that overlaps and fits with the third sector; The oil groove on the first sector and the third oil hole on the fourth sector, which overlaps and fits with the first sector, are misaligned and isolated; The first minimum distance between the oil groove and the central axis of the stator core is greater than the second minimum distance between the first oil hole and the central axis. The second minimum distance value is greater than the third minimum distance value between the second oil hole and the central axis; The third minimum distance value is greater than the fourth minimum distance value between the third oil hole and the central axis.

[0019] Furthermore, the second oil inlet section, the main body section, and the first oil inlet section are all formed by stacking multiple first stator laminations; the first oil outlet section and the second oil outlet section are both formed by stacking multiple second stator laminations.

[0020] Furthermore, the first oil outlet section is divided into a first segment and a second segment along its axial direction. The first segment is located on the side away from the second oil inlet section, and the second segment is located on the side close to the second oil inlet section. The second oil outlet section is divided into a third section and a fourth section along its axial direction. The third section is located on the side away from the first oil inlet section, and the fourth section is located on the side close to the first oil inlet section. The first segment, the second segment, the third segment, and the fourth segment are all composed of multiple second stator laminations stacked together; The projections of the fourth sector on any second stator lamination in the first segment onto the radial section of the stator core, the projections of the third sector on any second stator lamination in the second segment onto the radial section, the projections of the second sector on any first stator lamination in the second oil inlet segment onto the radial section, the projections of the first sector on any first stator lamination in the first oil inlet segment onto the radial section, the projections of the fourth sector on any second stator lamination in the fourth segment onto the radial section, and the projections of the third sector on any second stator lamination in the third segment all coincide.

[0021] In the above scheme B, by making the projections of each of the fourth sector portions on any second stator lamination in the first segment onto the radial section of the stator core, the projections of each of the third sector portions on any second stator lamination in the second segment onto the radial section, the projections of each of the second sector portions on any first stator lamination in the second oil inlet segment onto the radial section, the projections of each of the first sector portions on any first stator lamination in the first oil inlet segment onto the radial section, the projections of each of the fourth sector portions on any second stator lamination in the fourth segment onto the radial section, and the projections of each of the third sector portions on any second stator lamination in the third segment all coincide (that is, making the projections of each of the second sector portions on any first stator lamination in the first oil inlet segment onto the radial section, the projections of each of the third sector portions on any second stator lamination in the fourth segment onto the radial section, and the projections of each of the third sector portions on any second stator lamination in the third segment all coincide). The projections of the fourth sector portions on any second stator lamination in the radial section all coincide; and the second minimum distance value is greater than the third minimum distance value, which is greater than the fourth minimum distance value; thus, three-layer stepped flow channels are formed radially inward at the ends of each first oil passage (i.e., the flow channels of each first oil passage in the second oil inlet section and the first oil outlet section) and the ends of each second oil passage (i.e., the flow channels of each second oil passage in the first oil inlet section and the second oil outlet section); so that the cooling oil in each first oil passage can form a centripetal jet oil flow when it flows out of the end face of the first end, directly cooling the end of the stator winding outside the first end, and so that the cooling oil in each second oil passage can form a centripetal jet oil flow when it flows out of the end face of the second end, directly cooling the end of the stator winding outside the second end; and compared with the above scheme A, the formation of the centripetal jet oil flow in scheme B is more stable and reliable.

[0022] Option C, the third oil passage further includes a third oil hole formed on the side of the fourth sector, the third oil hole extending along the axial direction of the fourth sector and penetrating the fourth sector; The first oil passage further includes a fourth oil hole formed on the side of the first sector portion, the fourth oil hole extending along the axial direction of the first sector portion and penetrating the first sector portion; The second oil hole on the third sector is connected to the third oil hole on the fourth sector that overlaps and fits with the third sector; The oil groove on the first sector and the third oil hole on the fourth sector, which overlaps and fits with the first sector, are misaligned and isolated; The fourth oil hole on the first sector and the first oil hole on the second sector that overlaps and fits with the first sector are misaligned and isolated; The fourth oil hole on the first sector is connected to the third oil hole on the fourth sector that overlaps and fits with the first sector; The first minimum distance between the oil groove and the central axis of the stator core is greater than the second minimum distance between the first oil hole and the central axis. The second minimum distance value is greater than the third minimum distance value between the second oil hole and the central axis; The third minimum distance value is greater than the fourth minimum distance value between the third oil hole and the central axis; The fourth minimum distance value is greater than the fifth minimum distance value between the fourth oil hole and the central axis.

[0023] Furthermore, the second oil inlet section, the main body section, and the first oil inlet section are all formed by stacking multiple first stator laminations; the first oil outlet section and the second oil outlet section are both formed by stacking multiple first stator laminations and multiple second stator laminations.

[0024] Furthermore, the first oil outlet section is divided into a fifth section, a sixth section, and a seventh section along its axial direction, and the seventh section is in contact with the second oil inlet section; The second oil outlet section is divided into the eighth, ninth and tenth sections along its axial direction, and the tenth section is in contact with the first oil inlet section; The sixth segment, the seventh segment, the ninth segment, and the tenth segment are all formed by stacking multiple second stator laminations; the fifth segment and the eighth segment are all formed by stacking multiple first stator laminations. The projections of the first sector on any first stator lamination in the fifth segment onto the radial section of the stator core, the projections of the fourth sector on any second stator lamination in the sixth segment onto the radial section, the projections of the third sector on any second stator lamination in the seventh segment onto the radial section, the projections of the second sector on any first stator lamination in the second oil inlet segment onto the radial section, the projections of the first sector on any first stator lamination in the first oil inlet segment onto the radial section, the projections of the fourth sector on any second stator lamination in the tenth segment onto the radial section, the projections of the third sector on any second stator lamination in the ninth segment onto the radial section, and the projections of the second sector on any first stator lamination in the eighth segment all coincide.

[0025] In the above scheme C, the projections of each first sector on any first stator lamination in the fifth segment onto the radial section of the stator core, the projections of each fourth sector on any second stator lamination in the sixth segment onto the radial section, the projections of each third sector on any second stator lamination in the seventh segment onto the radial section, the projections of each second sector on any first stator lamination in the second oil inlet section onto the radial section, and the projections of each first sector on any first stator lamination in the first oil inlet section onto the radial section are all considered. The projections on the surface, the projections of the fourth sector portions on any second stator lamination in the tenth segment onto the radial section, the projections of the third sector portions on any second stator lamination in the ninth segment onto the radial section, and the projections of the second sector portions on any first stator lamination in the eighth segment all coincide (i.e., the projections of the second sector portions on any first stator lamination in the first oil inlet segment onto the radial section, and the projections of the third sector portions on any second stator lamination in the tenth segment onto the radial section). The projections of the fourth sector on the radial section of any second stator lamination in the ninth segment and the projections of the first sector on the radial section of any first stator lamination in the eighth segment all coincide; and the second minimum distance value is greater than the third minimum distance value, the third minimum distance value is greater than the fourth minimum distance value, and the fourth minimum distance value is greater than the fifth minimum distance value; that is, at the end of each first oil passage (i.e., the flow channel of each first oil passage in the second oil inlet section and the first oil outlet section) and at the end of each second oil passage ( That is, each of the second oil passages forms a four-layer stepped flow channel in the radial direction within the first oil inlet section and the second oil outlet section; so that the cooling oil in each of the first oil passages can form a centripetal jet of oil when it flows out of the end face of the first end, directly cooling the end of the stator winding outside the first end, and so that the cooling oil in each of the second oil passages can form a centripetal jet of oil when it flows out of the end face of the second end, directly cooling the end of the stator winding outside the second end; and compared with the above schemes A and B, the formation of the centripetal jet of oil in scheme C is more stable and reliable.

[0026] Option D, the third oil passage further includes a third oil hole formed on the side of the fourth sector, the third oil hole extending along the axial direction of the fourth sector and penetrating the fourth sector; The first oil passage further includes a fourth oil hole formed on the side of the first sector portion, the fourth oil hole extending along the axial direction of the first sector portion and penetrating the first sector portion; The second oil passage also includes a fifth oil hole formed on the side of the second sector portion, the fifth oil hole extending along the axial direction of the second sector portion and penetrating the second sector portion; The second oil hole on the third sector is connected to the third oil hole on the fourth sector that overlaps and fits with the third sector; The oil groove on the first sector and the third oil hole on the fourth sector, which overlaps and fits with the first sector, are misaligned and isolated; The fourth oil hole on the first sector and the first oil hole on the second sector that overlaps and fits with the first sector are misaligned and isolated; The fourth oil hole on the first sector is connected to the third oil hole on the fourth sector that overlaps and fits with the first sector; The fourth oil hole on the first sector and the fifth oil hole on the second sector that overlaps and fits with the first sector are connected; The oil groove on the first sector and the fifth oil hole on the second sector that overlaps and fits with the first sector are misaligned and isolated; The fifth oil hole on the second sector and the second oil hole on the third sector that overlaps and fits with the second sector are misaligned and isolated; The first minimum distance between the oil groove and the central axis of the stator core is greater than the second minimum distance between the first oil hole and the central axis. The second minimum distance value is greater than the third minimum distance value between the second oil hole and the central axis; The third minimum distance value is greater than the fourth minimum distance value between the third oil hole and the central axis; The fourth minimum distance value is greater than the fifth minimum distance value between the fourth oil hole and the central axis; The fifth minimum distance value is greater than the sixth minimum distance value between the fifth oil hole and the central axis.

[0027] Furthermore, the second oil inlet section, the main body section, and the first oil inlet section are all formed by stacking multiple first stator laminations; the first oil outlet section and the second oil outlet section are both formed by stacking multiple first stator laminations and multiple second stator laminations.

[0028] Furthermore, the first oil outlet section is divided into eleventh, twelfth, thirteenth and fourteenth sections along its axial direction, and the fourteenth section is in contact with the second oil inlet section; The second oil outlet section is divided into the fifteenth, sixteenth, seventeenth and eighteenth sections along its axial direction, and the eighteenth section is in contact with the first oil inlet section; The thirteenth, fourteenth, seventeenth, and eighteenth segments are all formed by stacking multiple second stator laminations; the eleventh, twelfth, fifteenth, and sixteenth segments are all formed by stacking multiple first stator laminations. The projections of the second sector portions on any first stator lamination in the eleventh segment onto the radial section of the stator core, the projections of the first sector portions on any first stator lamination in the twelfth segment onto the radial section, the projections of the fourth sector portions on any second stator lamination in the thirteenth segment onto the radial section, the projections of the third sector portions on any second stator lamination in the fourteenth segment onto the radial section, and the projections of the second sector portions on any first stator lamination in the second oil inlet section onto the radial section. The projections of each first sector on any first stator lamination in the first oil inlet section, each fourth sector on any second stator lamination in the eighteenth segment, each third sector on any second stator lamination in the seventeenth segment, each second sector on any first stator lamination in the sixteenth segment, and each first sector on any first stator lamination in the fifteenth segment all coincide on the radial section.

[0029] In the above scheme D, by projecting the second sector portion on any first stator lamination in the eleventh segment onto the radial section of the stator core, the projection of the first sector portion on any first stator lamination in the twelfth segment onto the radial section, the projection of the fourth sector portion on any second stator lamination in the thirteenth segment onto the radial section, the projection of the third sector portion on any second stator lamination in the fourteenth segment onto the radial section, the projection of the second sector portion on any first stator lamination in the second oil inlet section onto the radial section, and the projection of the first sector portion on any first stator lamination in the first oil inlet section onto the radial section, the projection of the second sector portion on any first stator lamination in the second oil inlet section onto the radial section, the projection of the first sector portion on any first stator lamination in the first oil inlet section onto the radial section, the projection of the second sector portion on any first stator lamination in the first oil inlet section onto the radial section, the projection of the second sector portion on any first stator lamination in the second ... The projections on the radial section, the projections on the radial section of each of the fourth sector portions on any of the second stator laminations in the eighteenth segment, the projections on the radial section of each of the third sector portions on any of the second stator laminations in the seventeenth segment, the projections on the radial section of each of the second sector portions on any of the first stator laminations in the sixteenth segment, and the projections on the radial section of each of the first sector portions on any of the first stator laminations in the fifteenth segment all coincide (that is, even if the projections on the radial section of each of the second sector portions on any of the first stator laminations in the first oil inlet section, and the projections on the radial section of each of the third sector portions on any of the second stator laminations in the eighteenth segment are all coincident). The projections on the radial section, the projections of the fourth sector portions on any second stator lamination in the seventeenth segment, the projections of the first sector portions on any first stator lamination in the sixteenth segment, and the projections of the second sector portions on any first stator lamination in the fifteenth segment all coincide; and the second minimum distance value is greater than the third minimum distance value, the third minimum distance value is greater than the fourth minimum distance value, the fourth minimum distance value is greater than the fifth minimum distance value, and the fifth minimum distance value is greater than the sixth minimum distance value; that is, at the end of each first oil passage (i.e., each first oil passage) Five radially inward stepped flow channels are formed at the ends of the second oil inlet section and the first oil outlet section (i.e., the flow channels of each second oil passage in the first oil inlet section and the second oil outlet section); so that the cooling oil in each first oil passage can form a centripetal jet oil flow when it flows out of the end face of the first end, directly cooling the end of the stator winding outside the first end, and so that the cooling oil in each second oil passage can form a centripetal jet oil flow when it flows out of the end face of the second end, directly cooling the end of the stator winding outside the second end; and compared with the above schemes A, B and C, the formation of the centripetal jet oil flow in scheme D is more stable and reliable.

[0030] The configuration of the oil delivery circuit includes various schemes, such as, but not limited to: Furthermore, the oil delivery circuit includes a cooling oil passage formed in the motor housing, an oil inlet formed on the outer surface of the motor housing, and a first annular groove and a second annular groove formed on the inner circumferential surface of the motor housing. Both the first annular groove and the second annular groove extend circumferentially along the motor housing; the first annular groove is correspondingly provided with the first oil inlet section, and the second annular groove is correspondingly provided with the second oil inlet section; The outer peripheral surface of the first oil inlet section covers the opening of the first annular groove, and the outer peripheral surface of the second oil inlet section covers the opening of the second annular groove; The two oil outlets of the oil conveying circuit are the first annular groove and the second annular groove, respectively. All of the first oil inlet ends are connected to the first annular groove, and all of the second oil inlet ends are connected to the second annular groove.

[0031] By covering the opening of the first annular groove with the outer peripheral surface of the first oil inlet section and the opening of the second annular groove with the outer peripheral surface of the second oil inlet section, the oil grooves on the multiple overlapping first sector portions in each first stator lamination of the first oil inlet section can be used to form the first oil inlet end of each first oil circuit, and the oil grooves on the multiple overlapping first sector portions in each first stator lamination of the second oil inlet section can be used to form the second oil inlet end of each second oil circuit, thereby ensuring that all the first oil inlet ends are connected to the first annular groove and all the second oil inlet ends are connected to the second annular groove.

[0032] Furthermore, a plurality of weld groove groups are provided on the outer peripheral surface of the stator core; each of the weld groove groups is evenly distributed along its circumference on the stator core; The weld groove group includes a first weld groove and a second weld groove that are spaced apart circumferentially along the stator core; both the first weld groove and the second weld groove extend axially along the stator core. The first weld groove is located in the first oil outlet section, and one end of the first weld groove extends to the end face of the first end. One end of the second weld groove extends to the first oil outlet section and is closed; the other end of the second weld groove extends to the end face of the second end; the minimum distance between the end of the second weld groove near the first end and the first end is less than the length of the first weld groove in the axial direction of the stator core. The inner circumferential surface of the motor housing is provided with an inwardly protruding positioning shoulder; the positioning shoulder is used to fit against the second end to complete the positioning of the stator core within the motor housing; The projections of each of the second weld grooves on the radial section of the stator core are all within the projection of the positioning shoulder on the radial section; The projection of the second oil outlet end of each of the second oil passages onto the radial section is outside the projection of the positioning shoulder onto the radial section.

[0033] Because existing stator cores are typically composed of hundreds or thousands of individual silicon steel laminations firmly stacked together, laser welding is a commonly used method to securely bond these laminations into a robust and compact core. To facilitate laser welding, weld grooves are pre-designed in the laminations; these grooves connect after the laminations are stacked to form weld beads for subsequent welding. However, the presence of weld beads often leads to oil leakage from the weld grooves. Cooling oil flows through the weld beads to both ends of the stator, failing to cool the stator core according to the pre-designed cooling flow path. This results in the actual cooling flow rate being lower than the design value, reducing the cooling effect.

[0034] The bidirectional oil-cooled motor stator heat dissipation structure provided by this invention ensures full axial coverage of the stator core by placing the first weld groove at the first oil outlet section, with one end of the first weld groove extending to the end face of the first end; and placing one end of the second weld groove at the first oil outlet section and closed off, with the other end of the second weld groove extending to the end face of the second end; and ensuring that the minimum distance between the end of the second weld groove near the first end and the first end is less than the length of the first weld groove in the axial direction of the stator core. Furthermore, since none of the first weld grooves connect to the first annular groove and the second annular groove, it ensures that none of the first weld grooves leak cooling oil. Although each of the second weld grooves connects to the first annular groove and the second annular groove, the projection of each of the second weld grooves on the radial section of the stator core is within the projection of the positioning shoulder on the radial section. This allows the positioning shoulder to cover and close the openings of each of the second weld grooves on the end face of the second end, ensuring that none of the second weld grooves leak cooling oil. Therefore, the bidirectional oil-cooled motor stator heat dissipation structure provided by this invention eliminates the oil leakage problem in either the first or second weld grooves.

[0035] Furthermore, a plurality of first connecting groove groups are formed on the outer peripheral surface of the first stator lamination, and each first connecting groove group is evenly distributed along the circumferential direction of the first stator lamination. A plurality of second connecting groove groups are formed on the outer peripheral surface of the second stator lamination, and each second connecting groove group is evenly distributed along the circumferential direction of the second stator lamination; The number of first connecting slot groups on the first stator lamination is the same as the number of second connecting slot groups on the second stator lamination; The first connecting groove group includes a first connecting groove formed on the outer arc surface of the first sector portion of a certain first sector group, and a second connecting groove formed on the outer arc surface of the second sector portion of the same first sector group. Both the first connecting groove and the second connecting groove extend along the axial direction of the first stator lamination. The central axis of the first connecting groove intersects the axis of symmetry of the first sector, and the central axis of the second connecting groove intersects the axis of symmetry of the second sector. The second connecting groove group includes a third connecting groove formed on the outer arc surface of the third sector of a certain second sector group, and a fourth connecting groove formed on the outer arc surface of the fourth sector of the same second sector group. Both the third connecting groove and the fourth connecting groove extend along the axial direction of the second stator lamination. The central axis of the third connecting groove intersects the axis of symmetry of the third sector, and the central axis of the fourth connecting groove intersects the axis of symmetry of the fourth sector. The number of first sector groups on the first stator lamination is an integer multiple of the number of first connecting groove groups, and the multiple is not less than two. The first connecting groove, the second connecting groove, the third connecting groove, and the fourth connecting groove are used to cooperate with each other to form each first weld groove and each second weld groove.

[0036] By evenly distributing each of the first connecting slot groups along the circumference of the first stator laminations, and each of the second connecting slot groups along the circumference of the second stator laminations, with the number of first connecting slot groups on the first stator laminations being the same as the number of second connecting slot groups on the second stator laminations, and the number of first sector groups on the first stator laminations being an integer multiple of the number of first connecting slot groups, and the multiple being not less than two; it is possible to utilize each of the first and second stator laminations to deflect and stack in a staggered manner, using the central angle of the sector (first sector, second sector, third sector, or fourth sector) as a unit to form the stator core, while simultaneously... Through overlapping and bonding between different sector sections, the first oil passage, the second oil passage and the third oil passage are used to form the first oil passage and the second oil passage on the stator core. At the same time, the first connecting groove, the second connecting groove, the third connecting groove and the fourth connecting groove are used to form the first welding groove, the second welding groove and a number of redundant groove segments on the stator core. It is ensured that these redundant groove segments will not connect the annular groove (i.e. the first annular groove and / or the second annular groove) with the end face of the stator core (i.e. the end face of the first end and / or the end face of the second end) to cause oil leakage.

[0037] The bidirectional oil-cooled motor stator heat dissipation structure provided by this invention has at least the following technical effects or advantages: 1. By setting up each of the first oil passages and each of the second oil passages, the bidirectional oil-cooled motor stator heat dissipation structure provided by the present invention actually forms multiple oil passages (including each of the first oil passages and each of the second oil passages) arranged circumferentially on the stator core. Furthermore, it enables any two adjacent oil passages to independently transport cooling oil in the opposite direction along the axial direction of the stator core (that is, the first oil passage transports cooling oil from the second end of the stator core to the first end and then flows out from the end face of the first end; the second oil passage transports cooling oil from the first end of the stator core to the second end and then flows out from the end face of the second end). By setting up bidirectional oil passages, the cooling uniformity of the stator core can be improved as much as possible, solving the technical problem of uneven cooling of the stator core due to the single axial flow direction of the cooling oil in the existing oil-cooled motor stator structure.

[0038] 2. Due to the trend towards lightweighting and miniaturization of electric drive systems, the design size of the oil flow channels in existing motor stator oil-cooling structures is usually small. This results in the cooling oil in existing motor stator oil-cooling structures typically being in a laminar flow state within the oil flow channels, with the boundary layer thickness gradually increasing along the flow direction, further exacerbating the problem of weakened heat exchange in the downstream region. However, by ensuring that the minimum distance between any two adjacent first flow channels and the central axis of the stator core is different, and the minimum distance between any two adjacent second flow channels and the central axis is also different, the bidirectional oil-cooled motor stator heat dissipation structure provided by this invention features first and second oil paths that are stepped flow channels along the cooling oil flow direction. The presence of the stepped structure can create turbulence, thereby disrupting or weakening the growth of the boundary layer, improving the problem of weakened heat exchange in the downstream region, increasing the heat exchange area, and enhancing the convective heat transfer effect of the cooling oil within the oil flow channels.

[0039] 3. By dividing the first stator laminations into first sector portions and second sector portions, and dividing the second stator laminations into third sector portions and fourth sector portions, and by opening a first oil channel on the first sector portion, a second oil channel on the second sector portion, and a third oil channel on the second sector portion, the first stator laminations and second stator laminations can be used to form the stator core by deflecting and stacking them in a staggered manner with the central angle of the sector portion (first sector portion, second sector portion, third sector portion, or fourth sector portion) as the unit. At the same time, by overlapping and bonding different sector portions, the first oil channel and the second oil channel are formed on the stator core.

[0040] 4. By covering the opening of the first annular groove with the outer peripheral surface of the first oil inlet section and the opening of the second annular groove with the outer peripheral surface of the second oil inlet section, the oil grooves on the multiple overlapping first sector portions in each first stator lamination of the first oil inlet section can be used to form the first oil inlet end of each first oil passage, and the oil grooves on the multiple overlapping first sector portions in each first stator lamination of the second oil inlet section can be used to form the second oil inlet end of each second oil passage, thereby ensuring that all the first oil inlet ends are connected to the first annular groove and all the second oil inlet ends are connected to the second annular groove.

[0041] 5. The bidirectional oil-cooled motor stator heat dissipation structure provided by the present invention ensures full axial coverage of the stator core by placing the first weld groove at the first oil outlet section and extending one end of the first weld groove to the end face of the first end; and by placing one end of the second weld groove to the first oil outlet section and enclosing it, and extending the other end of the second weld groove to the end face of the second end; and by placing the minimum distance between the end of the second weld groove near the first end and the first end less than the length of the first weld groove in the axial direction of the stator core; and since each of the first weld grooves does not connect the first annular groove and the second annular groove, it can be ensured that each of the first weld grooves will not leak cooling oil; and although each of the second weld grooves will connect the first annular groove and the second annular groove, since the projection of each of the second weld grooves on the radial section of the stator core is within the projection of the positioning shoulder on the radial section, the positioning shoulder can cover and close the opening of each of the second weld grooves on the end face of the second end, ensuring that each of the second weld grooves will not leak cooling oil; thus, the bidirectional oil-cooled motor stator heat dissipation structure provided by the present invention will not have the problem of oil leakage in each of the first weld grooves and each of the second weld grooves.

[0042] 6. By ensuring that each of the first connecting slot groups is evenly distributed along the circumference of the first stator laminations, and each of the second connecting slot groups is evenly distributed along the circumference of the second stator laminations, with the number of first connecting slot groups on the first stator laminations being the same as the number of second connecting slot groups on the second stator laminations, and the number of first sector groups on the first stator laminations being an integer multiple of the number of first connecting slot groups, and the multiple being not less than two; it is possible to utilize each of the first and second stator laminations to form the stator core by offsetting and stacking them in a staggered manner with the central angle of the sector (first sector, second sector, third sector, or fourth sector) as the unit, while... By overlapping and fitting different sector sections, the first oil passage, the second oil passage, and the third oil passage are used to form the first oil passage and the second oil passage on the stator core. At the same time, the first connecting groove, the second connecting groove, the third connecting groove, and the fourth connecting groove are used to form the first weld groove, the second weld groove, and a number of redundant groove segments on the stator core. It is ensured that these redundant groove segments will not connect the annular groove (i.e., the first annular groove and / or the second annular groove) with the end face of the stator core (i.e., the end face of the first end and / or the end face of the second end) to cause oil leakage. Attached Figure Description

[0043] To more clearly illustrate the technical solution of the present invention, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0044] Figure 1 This is a cross-sectional view of the stator heat dissipation structure of the bidirectional oil-cooled motor in the embodiment; Figure 2 This is a schematic diagram of the three-dimensional structure of the stator core in the embodiment. Figure 1 ; Figure 3 This is a schematic diagram of the three-dimensional structure of the stator core in the embodiment. Figure 2 ; Figure 4 This is a schematic diagram of the structure of the first stator lamination in the embodiment. Figure 1 ; Figure 5 This is a schematic diagram of the structure of the second stator lamination in the embodiment. Figure 1 ; Figure 6 This is a schematic diagram of the exploded structure of the stator core in the embodiment; Figure 7 This is a schematic diagram of the spatial structure of the first and second oil passages in the embodiment; Figure 8This is a structural perspective view of the motor housing in the embodiment; Figure 9 This is a schematic diagram of the structure of the first stator lamination in the embodiment. Figure 2 ; Figure 10 This is a schematic diagram of the structure of the second stator lamination in the embodiment. Figure 2 ; Figure 11 This is a schematic diagram of the structure of the outer peripheral surface of the stator core in the embodiment; Among them, 1-motor housing, 2-stator core, 3-stator winding; 1.1-Oil return port, 1.2-Cooling oil passage, 1.3-Oil inlet, 1.4-First annular groove, 1.5-Second annular groove, 1.6-Positioning shoulder; 2.1-First oil outlet section, 2.2-Second oil inlet section, 2.3-Main body section, 2.4-First oil inlet section, 2.5-Second oil outlet section, 2.6-First oil passage, 2.7-Second oil passage, 2.8-First sector group, 2.9-Second sector group, 2.10-First welding groove, 2.11-Second welding groove, 2.12-Wire embedding groove, 2.13-Redundant groove section; 2.1.1 - Eleventh segment, 2.1.2 - Twelfth segment, 2.1.3 - Thirteenth segment, 2.1.4 - Fourteenth segment; 2.3.1 - Main body sub-segmentation; 2.5.1 - Segment 15, 2.5.2 - Segment 16, 2.5.3 - Segment 17, 2.5.4 - Segment 18; 2.6.1 - First oil outlet end, 2.6.2 - First oil inlet end, 2.6.3 - First flow channel; 2.7.1 - Second oil outlet, 2.7.2 - Second oil inlet, 2.7.3 - Second flow channel; 2.8.1 - First sector; 2.8.1.1 - Oil groove, 2.8.1.2 - Fourth oil hole, 2.8.1.3 - First connecting groove; 2.8.2 - Second sector; 2.8.2.1 - First oil hole, 2.8.2.2 - Fifth oil hole, 2.8.2.3 - Second connecting groove; 2.9.1 - Third sector; 2.9.1.1 - Second oil hole; 2.9.1.2 - Third connecting groove; 2.9.2 - Fourth sector; 2.9.2.1 - Third oil hole, 2.9.2.2 - Fourth connecting groove. Detailed Implementation

[0045] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0046] like Figure 1 , Figure 2 , Figure 3 and Figure 7 As shown, this embodiment provides a bidirectional oil-cooled motor stator heat dissipation structure, including: a motor housing 1, and a stator core 2 installed inside the motor housing 1; the outer peripheral surface of the stator core 2 is interference-fitted with the inner peripheral surface of the motor housing 1; The stator core 2 is divided into the first oil outlet section 2.1, the second oil inlet section 2.2, the main body section 2.3, the first oil inlet section 2.4, and the second oil outlet section 2.5 along its axial direction from its first end to its second end. Multiple oil passage units are spaced apart along the circumference in the stator core 2. The oil passage units include a first oil passage 2.6 and a second oil passage 2.7. The first oil passage 2.6 and the second oil passage 2.7 are arranged spaced apart along the circumference of the stator core 2. Both the first oil passage 2.6 and the second oil passage 2.7 extend axially on the stator core 2. The first oil outlet end 2.6.1 of the first oil passage 2.6 extends to the end face of the first end, and the first oil inlet end 2.6.2 of the first oil passage 2.6 extends to the outer peripheral surface of the first oil inlet section 2.4; The second oil outlet end 2.7.1 of the second oil passage 2.7 extends to the end face of the second end, and the second oil inlet end 2.7.2 of the second oil passage 2.7 extends to the outer circumferential surface of the second oil inlet section 2.2; An oil conveying passage is provided in the motor housing 1. The oil conveying passage is provided with an oil inlet 1.3 and two oil outlets. The oil inlet 1.3 is located on the outer surface of the motor housing 1, and the two oil outlets are located on the inner circumferential surface of the motor housing 1. One oil outlet is connected to all the first oil inlets 2.6.2, and the other oil outlet is connected to all the second oil inlets 2.7.2.

[0047] By setting up each first oil passage 2.6 and each second oil passage 2.7, the bidirectional oil-cooled motor stator heat dissipation structure provided by the present invention not only forms multiple oil passages (including each first oil passage 2.6 and each second oil passage 2.7) arranged circumferentially on the stator core 2, but also enables any two adjacent oil passages to independently transport cooling oil in the opposite direction along the axial direction of the stator core 2 (that is, the first oil passage 2.6 transports cooling oil from the second end of the stator core 2 to the first end and then flows out from the end face of the first end; the second oil passage 2.7 transports cooling oil from the first end of the stator core 2 to the second end and then flows out from the end face of the second end). By setting up bidirectional oil passages, the cooling uniformity of the stator core 2 can be improved as much as possible, solving the technical problem of the existing oil-cooled motor stator structure having a single flow direction of cooling oil in the axial direction of the stator core 2 and uneven cooling of the stator core 2.

[0048] The flow direction of the cooling oil in the first oil passage 2.6 is as follows: Figure 3 and Figure 7 As shown by the blue arrow, the cooling oil flows in the second oil passage 2.7 in the following direction. Figure 3 and Figure 7 As shown by the green arrow in the image.

[0049] Preferably, in this embodiment, such as Figure 3 and Figure 7 As shown, the first oil passage 2.6 is divided into multiple sequentially connected first flow channels 2.6.3 along the axial direction of the stator core 2, and the second oil passage 2.7 is divided into multiple sequentially connected second flow channels 2.7.3 along the axial direction of the stator core 2; each first flow channel 2.6.3 and each second flow channel 2.7.3 extends along the axial direction of the stator core 2. The minimum distance between any two adjacent first flow channels 2.6.3 and the central axis of stator core 2 is different; the minimum distance between any two adjacent second flow channels 2.7.3 and the central axis is also different.

[0050] Due to the trend towards lightweighting and miniaturization of electric drive systems, the design size of the oil flow channels in existing motor stator oil-cooled structures is typically small. This results in the cooling oil in existing stator oil-cooled structures generally flowing in a laminar state within the oil flow channels, with the boundary layer thickness gradually increasing along the flow direction, further exacerbating the problem of weakened heat exchange in the downstream region. However, by ensuring that the minimum distances between any two adjacent first flow channels 2.6.3 and the central axis of the stator core 2 are all different, and that the minimum distances between any two adjacent second flow channels 2.7.3 and the central axis are also different, the bidirectional oil-cooled motor stator heat dissipation structure provided by this invention ensures that the first oil passage 2.6 and the second oil passage 2.7 are both stepped flow channels along the cooling oil flow direction. The presence of this stepped structure can create turbulence, thereby disrupting or weakening the growth of the boundary layer, improving the problem of weakened heat exchange in the downstream region, and also increasing the heat exchange area. Improve the convective heat transfer effect of cooling oil in the oil flow channel.

[0051] Specifically, in this embodiment, such as Figures 1 to 7 As shown, the stator core 2 is composed of multiple first stator laminations and multiple second stator laminations stacked together; The first stator lamination is divided into multiple first sector groups 2.8 along the circumferential direction. The first sector group 2.8 is further divided into a first sector portion 2.8.1 and a second sector portion 2.8.2 along the circumferential direction. A second sector portion 2.8.2 is provided between any two adjacent first sector portions 2.8.1. The second stator lamination is divided into multiple second sector groups 2.9 along the circumferential direction. The second sector group 2.9 is further divided into a third sector 2.9.1 and a fourth sector 2.9.2 along the circumferential direction. A fourth sector 2.9.2 is provided between any two adjacent third sector 2.9.1. The central angles of the first sector 2.8.1, the second sector 2.8.2, the third sector 2.9.1, and the fourth sector 2.9.2 are equal; A first oil passage is provided on the first sector 2.8.1, a second oil passage is provided on the second sector 2.8.2, and a third oil passage is provided on the second sector group 2.9; The first oil passage includes an oil groove 28.1.1 formed on the outer arc surface of the first sector 28.1. The oil groove 28.1.1 extends along the axial direction of the first sector 28.1 and penetrates the first sector 28.1. The second oil passage includes a first oil hole 2.8.2.1 opened on the side of the second sector 2.8.2. The first oil hole 2.8.2.1 extends along the axial direction of the second sector 2.8.2 and penetrates the second sector 2.8.2. The third oil passage includes a second oil hole 2.9.1.1 opened on the side of the third sector 2.9.1. The second oil hole 2.9.1.1 extends along the axial direction of the third sector 2.9.1 and penetrates the third sector 2.9.1. The oil groove 28.1.1 on the first sector 2.8.1 and the first oil hole 28.2.1 on the second sector 2.8.2 that overlaps and fits with the first sector 2.8.1 are connected; The first oil hole 2.8.2.1 on the second sector 2.8.2 and the second oil hole 2.9.1.1 on the third sector 2.9.1 that overlaps and fits with the second sector 2.8.2 are connected; When the first sector 2.8.1 and the fourth sector 2.9.2 overlap and fit together, the fourth sector 2.9.2 blocks the end of the oil groove 2.8.1.1 on the first sector 2.8.1 facing the fourth sector 2.9.2; The first oil passage, the second oil passage, and the third oil passage are used to cooperate with each other to form each first oil passage 2.6 and each second oil passage 2.7.

[0052] By dividing the first stator laminations into first sector portions 2.8.1 and second sector portions 2.8.2, and the second stator laminations into third sector portions 2.9.1 and fourth sector portions 2.9.2, and by opening a first oil channel on the first sector portion 2.8.1, a second oil channel on the second sector portion 2.8.2, and a third oil channel on the second sector group 2.9, the stator core 2 can be formed by deflecting and stacking the first and second stator laminations in a staggered manner with the central angle of the sector portion (first sector portion 2.8.1, second sector portion 2.8.2, third sector portion 2.9.1 or fourth sector portion 2.9.2) as the unit. At the same time, by overlapping and bonding the different sector portions, first oil passages 2.6 and second oil passages 2.7 are formed on the stator core 2.

[0053] Preferably, in this embodiment, such as Figure 1 and Figure 8 As shown, an oil return port 1.1 is also provided on the front end and / or rear end of the motor housing 1.

[0054] Specifically, in this embodiment, such as Figure 1 and Figure 8 As shown, oil return ports 1.1 are provided on both the front and rear ends of the motor housing 1.

[0055] Specifically, in this embodiment, such as Figure 4 and Figure 5 As shown, multiple slots 2.12 are provided on the inner circumferential surfaces of the first stator lamination and the second stator lamination.

[0056] Specifically, in this embodiment, such as Figure 4 and Figure 5 As shown, each of the first sector 2.8.1 has a wire groove 2.12 on its inner arc surface, each of the second sector 2.8.2 has a wire groove 2.12 on its inner arc surface, each of the third sector 2.9.1 has a wire groove 2.12 on its inner arc surface, and each of the fourth sector 2.9.2 has a wire groove 2.12 on its inner arc surface; the wire grooves 2.12 on the inner circumferential surface of the first stator lamination are evenly distributed along its circumference, and the wire grooves 2.12 on the inner circumferential surface of the second stator lamination are evenly distributed along its circumferential direction.

[0057] In this embodiment, there are multiple specific stacking schemes for forming the stator core 2 by stacking the first stator laminations and the second stator laminations. However, due to space limitations, this embodiment will only provide examples of four stacking schemes. It should be noted that the following four stacking schemes do not constitute any limitation on the scope of protection of this invention. All stacking schemes formed by equivalent transformations or equivalent substitutions fall within the scope of protection of this invention.

[0058] In the stacking scheme one, the first oil outlet section 2.1 and the second oil outlet section 2.5 are both composed of multiple second stator laminations; the second oil inlet section 2.2, the main body section 2.3 and the first oil inlet section 2.4 are all composed of multiple first stator laminations.

[0059] Specifically, in stacking scheme one, the projections of each third sector 2.9.1 on the radial section of the stator core 2 on any second stator lamination in the first oil outlet section 2.1, the projections of each second sector 2.8.2 on the radial section of any first stator lamination in the second oil inlet section 2.2, the projections of each first sector 2.8.1 on the radial section of any first stator lamination in the first oil inlet section 2.4, and the projections of each fourth sector 2.9.2 on the radial section of any second stator lamination in the second oil outlet section 2.5 all coincide; Each oil groove 2.8.1.1 on the first oil inlet section 2.4 is connected to one of the oil outlets, and each oil groove 2.8.1.1 on the second oil inlet section 2.2 is connected to the other oil outlet.

[0060] Preferably, in stacking scheme one, the main body segment 2.3 is divided into multiple main body sub-segments 2.3.1 along its axial direction; Each main sub-segment 2.3.1 is composed of multiple first stator laminations stacked together; The projection of each first sector 2.8.1 on the radial section of any first stator lamination in any main body sub-segment 2.3.1 coincides with the projection of each second sector 2.8.2 on the radial section of any first stator lamination in the adjacent main body sub-segment 2.3.1.

[0061] Preferably, in stacking scheme one, the projection of each second sector 2.8.2 on the radial section of any first stator lamination in the main body sub-segment 2.3.1 closest to the second oil inlet section 2.2 coincides with the projection of each first sector 2.8.1 on the radial section of any first stator lamination in the second oil inlet section 2.2; The projection of the second sector 2.8.2 on the radial section of any first stator lamination in the main body sub-segment 2.3.1 closest to the first oil inlet section 2.4 coincides with the projection of the first sector 2.8.1 on the radial section of any first stator lamination in the first oil inlet section 2.4.

[0062] Specifically, in stacking scheme one, the first minimum distance between the oil groove 2.8.1.1 and the central axis of the stator core 2 is greater than the second minimum distance between the first oil hole 2.8.2.1 and the central axis; The second minimum distance value is greater than the third minimum distance value between the second oil hole 2.9.1.1 and the central axis.

[0063] In the aforementioned stacking scheme one, the projections of each third sector 2.9.1 on the radial section of the stator core 2 of any second stator lamination in the first oil outlet section 2.1, the projections of each second sector 2.8.2 on the radial section of any first stator lamination in the second oil inlet section 2.2, the projections of each first sector 2.8.1 on the radial section of any first stator lamination in the first oil inlet section 2.4, and the projections of each fourth sector 2.9.2 on the radial section of any second stator lamination in the second oil outlet section 2.5 all coincide (that is, the projections of each second sector 2.8.2 on the radial section of any first stator lamination in the first oil inlet section 2.4 and the projections of each third sector 2.9.1 on the radial section of any second stator lamination in the second oil outlet section 2.5 all coincide). The projections on the radial section all coincide); and the second minimum distance value is greater than the third minimum distance value; thus, a double-layer stepped flow channel is formed radially inward at the end of each first oil passage 2.6 (that is, the flow channel of each first oil passage 2.6 in the second oil inlet section 2.2 and the first oil outlet section 2.1) and the end of each second oil passage 2.7 (that is, the flow channel of each second oil passage 2.7 in the first oil inlet section 2.4 and the second oil outlet section 2.5); so that the cooling oil in each first oil passage 2.6 can form a centripetal jet oil flow when it flows out of the end face of the first end, directly cooling the end of the stator winding 3 outside the first end, and so that the cooling oil in each second oil passage 2.7 can form a centripetal jet oil flow when it flows out of the end face of the second end, directly cooling the end of the stator winding 3 outside the second end. Compared to the existing oil-cooled structure of motor stators, which typically installs oil spray rings at both ends of the stator core 2 to ensure the formation of centripetal oil jet, the bidirectional oil-cooled motor stator heat dissipation structure provided by the above scheme A not only eliminates the need for oil spray rings, saving the installation space required by the oil spray rings and facilitating the miniaturization design of oil-cooled motors, but also saves on the process costs caused by the sealing process between the oil spray rings, motor housing 1 and stator core 2.

[0064] In the second stacking scheme, the third oil passage further includes a third oil hole 2.9.2.1 opened on the side of the fourth sector 2.9.2. The third oil hole 2.9.2.1 extends along the axial direction of the fourth sector 2.9.2 and penetrates the fourth sector 2.9.2. The second oil hole 2.9.1.1 on the third sector 2.9.1 is connected to the third oil hole 2.9.2.1 on the fourth sector 2.9.2 which overlaps and fits with the third sector 2.9.1; The oil groove 2.8.1.1 on the first sector 2.8.1 and the third oil hole 2.9.2.1 on the fourth sector 2.9.2 that overlaps and fits with the first sector 2.8.1 are misaligned and isolated; The first minimum distance between the oil groove 2.8.1.1 and the central axis of the stator core 2 is greater than the second minimum distance between the first oil hole 2.8.2.1 and the central axis. The second minimum distance value is greater than the third minimum distance value between the second oil hole 2.9.1.1 and the central axis; The third minimum distance value is greater than the fourth minimum distance value between the third oil hole 2.9.2.1 and the central axis.

[0065] Specifically, in stacking scheme two, the second oil inlet section 2.2, the main body section 2.3 and the first oil inlet section 2.4 are all formed by stacking multiple first stator laminations; the first oil outlet section 2.1 and the second oil outlet section 2.5 are both formed by stacking multiple second stator laminations.

[0066] Specifically, in stacking scheme two, the first oil outlet section 2.1 is divided into a first segment and a second segment along its axial direction. The first segment is located on the side away from the second oil inlet section 2.2, and the second segment is located on the side close to the second oil inlet section 2.2. The second oil outlet section 2.5 is divided into a third section and a fourth section along its axial direction. The third section is located on the side away from the first oil inlet section 2.4, and the fourth section is located on the side close to the first oil inlet section 2.4. The first segment, the second segment, the third segment, and the fourth segment are all composed of multiple second stator laminations stacked together; The projections of the fourth sector 2.9.2 on any second stator lamination in the first segment onto the radial section of the stator core 2, the projections of the third sector 2.9.1 on any second stator lamination in the second segment onto the radial section, the projections of the second sector 2.8.2 on any first stator lamination in the second oil inlet section 2.2 onto the radial section, the projections of the first sector 2.8.1 on any first stator lamination in the first oil inlet section 2.4 onto the radial section, the projections of the fourth sector 2.9.2 on any second stator lamination in the fourth segment onto the radial section, and the projections of the third sector 2.9.1 on any second stator lamination in the third segment all coincide.

[0067] Preferably, in stacking scheme two, the main body segment 2.3 is divided into multiple main body sub-segments 2.3.1 along its axial direction; Each main sub-segment 2.3.1 is composed of multiple first stator laminations stacked together; The projection of each first sector 2.8.1 on the radial section of any first stator lamination in any main body sub-segment 2.3.1 coincides with the projection of each second sector 2.8.2 on the radial section of any first stator lamination in the adjacent main body sub-segment 2.3.1.

[0068] Preferably, in stacking scheme two, the projection of each second sector 2.8.2 on the radial section of any first stator lamination in the main body sub-segment 2.3.1 closest to the second oil inlet section 2.2 coincides with the projection of each first sector 2.8.1 on the radial section of any first stator lamination in the second oil inlet section 2.2; The projection of the second sector 2.8.2 on the radial section of any first stator lamination in the main body sub-segment 2.3.1 closest to the first oil inlet section 2.4 coincides with the projection of the first sector 2.8.1 on the radial section of any first stator lamination in the first oil inlet section 2.4.

[0069] In the aforementioned stacking scheme two, the projections of the fourth sector 2.9.2 on any second stator lamination in the first segment onto the radial section of the stator core 2, the projections of the third sector 2.9.1 on any second stator lamination in the second segment onto the radial section, the projections of the second sector 2.8.2 on any first stator lamination in the second oil inlet section 2.2 onto the radial section, and the projections of the first sector 2.8.1 on any first stator lamination in the first oil inlet section 2.4 onto the radial section of the stator core 2 are all achieved. The projections on the cross section, the projections on the radial sections of each of the fourth sector portions 2.9.2 on any second stator lamination in the fourth segment, and the projections on the radial sections of each of the third sector portions 2.9.1 on any second stator lamination in the third segment all coincide (that is, the projections on the radial sections of each of the second sector portions 2.8.2 on any first stator lamination in the first oil inlet section 2.4, and the projections on the radial sections of each of the third sector portions 2.9.1 on any second stator lamination in the fourth segment, all coincide with the projections on the radial sections of the third segment). The projections of each fourth sector 2.9.2 on the radial section of any second stator lamination in the segment coincide; and the second minimum distance value is greater than the third minimum distance value, and the third minimum distance value is greater than the fourth minimum distance value; that is, at the end of each first oil passage 2.6 (that is, in the flow channels of each first oil passage 2.6 in the second oil inlet section 2.2 and the first oil outlet section 2.1) and at the end of each second oil passage 2.7 (that is, in the flow channels of each second oil passage 2.7 in the first oil inlet section 2.4 and the second oil outlet section 2.5) A three-layer stepped flow channel is formed radially inward; the cooling oil in each first oil passage 2.6 can form a centripetal jet of oil when it flows out of the end face of the first end, directly cooling the end of the stator winding 3 outside the first end, and the cooling oil in each second oil passage 2.7 can form a centripetal jet of oil when it flows out of the end face of the second end, directly cooling the end of the stator winding 3 outside the second end; and compared with the above stacking scheme one, the formation of the centripetal jet of oil in stacking scheme two is more stable and reliable.

[0070] In the third stacking scheme, the third oil passage also includes a third oil hole 2.9.2.1 opened on the side of the fourth sector 2.9.2. The third oil hole 2.9.2.1 extends along the axial direction of the fourth sector 2.9.2 and penetrates the fourth sector 2.9.2. The first oil passage also includes a fourth oil hole 2.8.1.2 opened on the side of the first sector 2.8.1, the fourth oil hole 2.8.1.2 extends along the axial direction of the first sector 2.8.1, and the fourth oil hole 2.8.1.2 penetrates the first sector 2.8.1; The second oil hole 2.9.1.1 on the third sector 2.9.1 is connected to the third oil hole 2.9.2.1 on the fourth sector 2.9.2 which overlaps and fits with the third sector 2.9.1; The oil groove 2.8.1.1 on the first sector 2.8.1 and the third oil hole 2.9.2.1 on the fourth sector 2.9.2 that overlaps and fits with the first sector 2.8.1 are misaligned and isolated; The fourth oil hole 2.8.1.2 on the first sector 2.8.1 and the first oil hole 2.8.2.1 on the second sector 2.8.2 that overlaps and fits with the first sector 2.8.1 are misaligned and isolated; The fourth oil hole 2.8.1.2 on the first sector 2.8.1 is connected to the third oil hole 2.9.2.1 on the fourth sector 2.9.2 that overlaps and fits with the first sector 2.8.1; The first minimum distance between the oil groove 2.8.1.1 and the central axis of the stator core 2 is greater than the second minimum distance between the first oil hole 2.8.2.1 and the central axis. The second minimum distance value is greater than the third minimum distance value between the second oil hole 2.9.1.1 and the central axis; The third minimum distance value is greater than the fourth minimum distance value between the third oil hole 2.9.2.1 and the central axis; The fourth minimum distance value is greater than the fifth minimum distance value between the fourth oil hole 2.8.1.2 and the central axis.

[0071] Specifically, in stacking scheme three, the second oil inlet section 2.2, the main body section 2.3 and the first oil inlet section 2.4 are all composed of multiple first stator laminations; the first oil outlet section 2.1 and the second oil outlet section 2.5 are both composed of multiple first stator laminations and multiple second stator laminations.

[0072] Specifically, in stacking scheme three, the first oil outlet section 2.1 is divided into the fifth, sixth and seventh sections along its axial direction, and the seventh section is attached to the second oil inlet section 2.2; The second oil outlet section 2.5 is divided into the eighth section, the ninth section and the tenth section along its axial direction. The tenth section is attached to the first oil inlet section 2.4. The sixth, seventh, ninth, and tenth segments are all composed of multiple second stator laminations; the fifth and eighth segments are all composed of multiple first stator laminations. The projections of each first sector 2.8.1 on any first stator lamination in the fifth segment onto the radial section of the stator core 2, the projections of each fourth sector 2.9.2 on any second stator lamination in the sixth segment onto the radial section, the projections of each third sector 2.9.1 on any second stator lamination in the seventh segment onto the radial section, the projections of each second sector 2.8.2 on any first stator lamination in the second oil inlet section 2.2 onto the radial section, the projections of each first sector 2.8.1 on any first stator lamination in the first oil inlet section 2.4 onto the radial section, the projections of each fourth sector 2.9.2 on any second stator lamination in the tenth segment onto the radial section, the projections of each third sector 2.9.1 on any second stator lamination in the ninth segment onto the radial section, and the projections of each second sector 2.8.2 on any first stator lamination in the eighth segment all coincide.

[0073] Preferably, in stacking scheme three, the main body segment 2.3 is divided into multiple main body sub-segments 2.3.1 along its axial direction; Each main sub-segment 2.3.1 is composed of multiple first stator laminations stacked together; The projection of each first sector 2.8.1 on the radial section of any first stator lamination in any main body sub-segment 2.3.1 coincides with the projection of each second sector 2.8.2 on the radial section of any first stator lamination in the adjacent main body sub-segment 2.3.1.

[0074] Preferably, in stacking scheme three, the projection of each second sector 2.8.2 on the radial section of any first stator lamination in the main body sub-segment 2.3.1 closest to the second oil inlet section 2.2 coincides with the projection of each first sector 2.8.1 on the radial section of any first stator lamination in the second oil inlet section 2.2; The projection of the second sector 2.8.2 on the radial section of any first stator lamination in the main body sub-segment 2.3.1 closest to the first oil inlet section 2.4 coincides with the projection of the first sector 2.8.1 on the radial section of any first stator lamination in the first oil inlet section 2.4.

[0075] In the aforementioned stacking scheme three, the projections of each first sector 2.8.1 on any first stator lamination in the fifth segment onto the radial section of the stator core 2, the projections of each fourth sector 2.9.2 on any second stator lamination in the sixth segment onto the radial section, the projections of each third sector 2.9.1 on any second stator lamination in the seventh segment onto the radial section, the projections of each second sector 2.8.2 on any first stator lamination in the second oil inlet section 2.2 onto the radial section, and the projections of each first sector 2.8 on any first stator lamination in the first oil inlet section 2.4 are all made using the following methods: 1. The projections of the second stator laminations on the radial section, 2.9.2, 2.9.1, 2.9.2, 2.9.1, 2.9.2, 2.9.1, 2.9.2, 2.8.2, 2.9.1, 2.9 ...2, 2.9.2, 2.9.2, 2.9.2, 2 The projections of the fourth sector 2.9.2 on any second stator lamination in the ninth segment and the first sector 2.8.1 on any first stator lamination in the eighth segment all coincide; and the second minimum distance value is greater than the third minimum distance value, the third minimum distance value is greater than the fourth minimum distance value, and the fourth minimum distance value is greater than the fifth minimum distance value; that is, at the end of each first oil passage 2.6 (that is, the flow channels of each first oil passage 2.6 in the second oil inlet section 2.2 and the first oil outlet section 2.1) and at the end of each second oil passage 2.7 (that is, the flow channels of each second oil passage 2.7 in the second oil outlet section 2.1) The flow path 2.7 forms a four-layer stepped flow path in the radial direction within the flow path in the first oil inlet section 2.4 and the second oil outlet section 2.5; so that the cooling oil in each first oil path 2.6 can form a centripetal jet of oil when it flows out of the end face of the first end, directly cooling the end of the stator winding 3 outside the first end, and so that the cooling oil in each second oil path 2.7 can form a centripetal jet of oil when it flows out of the end face of the second end, directly cooling the end of the stator winding 3 outside the second end; and compared with the stacking scheme one and stacking scheme two, the formation of the centripetal jet of oil in stacking scheme three is more stable and reliable.

[0076] Stacking scheme four, in which, as Figure 4 and Figure 5 As shown, the third oil passage also includes a third oil hole 2.9.2.1 opened on the side of the fourth sector 2.9.2. The third oil hole 2.9.2.1 extends along the axial direction of the fourth sector 2.9.2 and penetrates the fourth sector 2.9.2. The first oil passage also includes a fourth oil hole 2.8.1.2 opened on the side of the first sector 2.8.1, the fourth oil hole 2.8.1.2 extends along the axial direction of the first sector 2.8.1, and the fourth oil hole 2.8.1.2 penetrates the first sector 2.8.1; The second oil passage also includes a fifth oil hole 2.8.2.2 opened on the side of the second sector 2.8.2. The fifth oil hole 2.8.2.2 extends along the axial direction of the second sector 2.8.2 and penetrates the second sector 2.8.2. The second oil hole 2.9.1.1 on the third sector 2.9.1 is connected to the third oil hole 2.9.2.1 on the fourth sector 2.9.2 which overlaps and fits with the third sector 2.9.1; The oil groove 2.8.1.1 on the first sector 2.8.1 and the third oil hole 2.9.2.1 on the fourth sector 2.9.2 that overlaps and fits with the first sector 2.8.1 are misaligned and isolated; The fourth oil hole 2.8.1.2 on the first sector 2.8.1 and the first oil hole 2.8.2.1 on the second sector 2.8.2 that overlaps and fits with the first sector 2.8.1 are misaligned and isolated; The fourth oil hole 2.8.1.2 on the first sector 2.8.1 is connected to the third oil hole 2.9.2.1 on the fourth sector 2.9.2 that overlaps and fits with the first sector 2.8.1; The fourth oil hole 2.8.1.2 on the first sector 2.8.1 and the fifth oil hole 2.8.2.2 on the second sector 2.8.2 that overlaps and fits with the first sector 2.8.1 are connected; The oil groove 2.8.1.1 on the first sector 2.8.1 and the fifth oil hole 2.8.2.2 on the second sector 2.8.2 that overlaps and fits with the first sector 2.8.1 are misaligned and isolated; The fifth oil hole 2.8.2.2 on the second sector 2.8.2 and the second oil hole 2.9.1.1 on the third sector 2.9.1, which overlaps and fits with the second sector 2.8.2, are misaligned and isolated; The first minimum distance between the oil groove 2.8.1.1 and the central axis of the stator core 2 is greater than the second minimum distance between the first oil hole 2.8.2.1 and the central axis. The second minimum distance value is greater than the third minimum distance value between the second oil hole 2.9.1.1 and the central axis; The third minimum distance value is greater than the fourth minimum distance value between the third oil hole 2.9.2.1 and the central axis; The fourth minimum distance value is greater than the fifth minimum distance value between the fourth oil hole 2.8.1.2 and the central axis; The fifth minimum distance value is greater than the sixth minimum distance value between the fifth oil hole 2.8.2.2 and the central axis.

[0077] Specifically, in stacking scheme four, such as Figure 6 As shown, the second oil inlet section 2.2, the main body section 2.3 and the first oil inlet section 2.4 are all composed of multiple first stator laminations; the first oil outlet section 2.1 and the second oil outlet section 2.5 are both composed of multiple first stator laminations and multiple second stator laminations.

[0078] Specifically, in stacking scheme four, such as Figure 2 , Figure 3 , Figure 6 and Figure 7 As shown, the first oil outlet section 2.1 is divided into the eleventh section 2.1.1, the twelfth section 2.1.2, the thirteenth section 2.1.3 and the fourteenth section 2.1.4 along its axial direction. The fourteenth section 2.1.4 is attached to the second oil inlet section 2.2. The second oil outlet section 2.5 is divided into the fifteenth section 2.5.1, the sixteenth section 2.5.2, the seventeenth section 2.5.3 and the eighteenth section 2.5.4 along its axial direction. The eighteenth section 2.5.4 is attached to the first oil inlet section 2.4. Section 13 (2.1.3), Section 14 (2.1.4), Section 17 (2.5.3), and Section 18 (2.5.4) are all composed of multiple second stator laminations; Section 11 (2.1.1), Section 12 (2.1.2), Section 15 (2.5.1), and Section 16 (2.5.2) are all composed of multiple first stator laminations. The projections of the second sector 2.8.2 on any first stator lamination in section 11 (2.1.1) onto the radial section of the stator core 2; the projections of the first sector 2.8.1 on any first stator lamination in section 12 (2.1.2) onto the radial section; the projections of the fourth sector 2.9.2 on any second stator lamination in section 13 (2.1.3) onto the radial section; the projections of the third sector 2.9.1 on any second stator lamination in section 14 (2.1.4) onto the radial section; and the projections of the second sector 2.8.2 on any first stator lamination in section 2.2 of the second oil inlet section onto the radial section. The projections of the first sector 2.8.1 on the radial section of any first stator lamination in the first oil inlet section 2.4, the projections of the fourth sector 2.9.2 on the radial section of any second stator lamination in the eighteenth section 2.5.4, the projections of the third sector 2.9.1 on the radial section of any second stator lamination in the seventeenth section 2.5.3, the projections of the second sector 2.8.2 on the radial section of any first stator lamination in the sixteenth section 2.5.2, and the projections of the first sector 2.8.1 on the radial section of any first stator lamination in the fifteenth section 2.5.1 all coincide.

[0079] Preferably, in stacking scheme four, such as Figure 6 As shown, the main body segment 2.3 is divided into multiple main body sub-segments 2.3.1 along its axial direction; Each main sub-segment 2.3.1 is composed of multiple first stator laminations stacked together; The projection of each first sector 2.8.1 on the radial section of any first stator lamination in any main body sub-segment 2.3.1 coincides with the projection of each second sector 2.8.2 on the radial section of any first stator lamination in the adjacent main body sub-segment 2.3.1.

[0080] Preferably, in stacking scheme four, such as Figure 6 As shown, the projection of each second sector 2.8.2 on the radial section of any first stator lamination in the main body sub-segment 2.3.1 closest to the second oil inlet section 2.2 coincides with the projection of each first sector 2.8.1 on the radial section of any first stator lamination in the second oil inlet section 2.2; The projection of the second sector 2.8.2 on the radial section of any first stator lamination in the main body sub-segment 2.3.1 closest to the first oil inlet section 2.4 coincides with the projection of the first sector 2.8.1 on the radial section of any first stator lamination in the first oil inlet section 2.4.

[0081] In the aforementioned stacking scheme four, the projections of the second sector 2.8.2 on any first stator lamination in the eleventh segment 2.1.1 onto the radial section of the stator core 2, the projections of the first sector 2.8.1 on any first stator lamination in the twelfth segment 2.1.2 onto the radial section, the projections of the fourth sector 2.9.2 on any second stator lamination in the thirteenth segment 2.1.3 onto the radial section, the projections of the third sector 2.9.1 on any second stator lamination in the fourteenth segment 2.1.4 onto the radial section, and the projections of the second sector 2.8.2 on any first stator lamination in the second oil inlet section 2.2 onto the radial section are all achieved by... The projections of the first sector 2.8.1 on any first stator lamination in the first oil inlet section 2.4, the fourth sector 2.9.2 on any second stator lamination in the eighteenth section 2.5.4, the third sector 2.9.1 on any second stator lamination in the seventeenth section 2.5.3, the second sector 2.8.2 on any first stator lamination in the sixteenth section 2.5.2, and the first sector 2.8.1 on any first stator lamination in the fifteenth section 2.5.1 all coincide (i.e., the projections of the first oil inlet section 2.4, the first sector 2.8.1 on any first stator lamination in the first oil inlet section 2.5.1, the second sector 2.8.1 on any first stator lamination in the first oil inlet section 2.5.1, the third sector 2.8.1 on any first stator lamination in the first oil inlet section 2.5.1, the fourth sector 2.8.2 on any second stator lamination in the first stator lamination in the first oil inlet section 2.5.1, the fifth sector 2.5.1, and the sixth sector 2.8.1 on any first stator lamination in the first oil inlet section 2.5.1, the sixth sector 2.8.1 on any first stator lamination in the first oil inlet section 2.5.1, the seventh sector 2.8.1, the eighth sector 2.8.1, the ninth sector 2.8.1, the tenth sector 2.8.1, the twentieth ... The projections of the second sector 2.8.2 on any first stator lamination in section 4, the projections of the third sector 2.9.1 on any second stator lamination in section 18, the projections of the fourth sector 2.9.2 on any second stator lamination in section 17, the projections of the first sector 2.8.1 on any first stator lamination in section 16, and the projections of the second sector 2.8.2 on any first stator lamination in section 15, all coincide, and the second minimum distance value is greater than the third minimum distance value. The third minimum distance value is greater than the fourth minimum distance value, the fourth minimum distance value is greater than the fifth minimum distance value, and the fifth minimum distance value is greater than the sixth minimum distance value; thus, five radially inward stepped flow channels are formed at the ends of each first oil passage 2.6 (i.e., the flow channels of each first oil passage 2.6 in the second oil inlet section 2.2 and the first oil outlet section 2.1) and the ends of each second oil passage 2.7 (i.e., the flow channels of each second oil passage 2.7 in the first oil inlet section 2.4 and the second oil outlet section 2.5); so that the cooling oil in each first oil passage 2.6 can form a centripetal jet of oil when it flows out of the end face of the first end, directly cooling the end of the stator winding 3 outside the first end, and so that each second oil passage 2.The cooling oil in section 7 forms a centripetal jet when it flows out of the end face of the second end, directly cooling the end of the stator winding 3 outside the second end; and compared with the above-mentioned stacking schemes one, two, and three, the formation of the centripetal jet oil flow in stacking scheme four is more stable and reliable.

[0082] Specifically, in this embodiment, the stacking scheme for forming the stator core 2 by stacking the first stator laminations and the second stator laminations adopts the stacking scheme four described above.

[0083] It should be noted that the specific illustrations for stacking scheme 1, stacking scheme 2, and stacking scheme 3 mentioned above can all be found by referring to... Figures 4 to 8 To understand this, you only need to remove some of the structures in the diagram by default.

[0084] The design of the oil delivery circuit includes various options, such as, but not limited to: In this embodiment, as Figure 1 , Figure 8 and Figure 11 As shown, the oil conveying circuit includes a cooling oil passage 1.2 formed in the motor housing 1, an oil inlet 1.3 formed on the outer surface of the motor housing 1, and a first annular groove 1.4 and a second annular groove 1.5 formed on the inner circumferential surface of the motor housing 1. The first annular groove 1.4 and the second annular groove 1.5 both extend circumferentially along the motor housing 1; the first annular groove 1.4 is correspondingly provided with the first oil inlet section 2.4, and the second annular groove 1.5 is correspondingly provided with the second oil inlet section 2.2; The outer circumferential surface of the first oil inlet section 2.4 covers the opening of the first annular groove 1.4, and the outer circumferential surface of the second oil inlet section 2.2 covers the opening of the second annular groove 1.5. The two oil outlets of the oil conveying circuit are the first annular groove 1.4 and the second annular groove 1.5, respectively; All the first oil inlet ends 2.6.2 are connected to the first annular groove 1.4, and all the second oil inlet ends 2.7.2 are connected to the second annular groove 1.5.

[0085] By covering the opening of the first annular groove 1.4 with the outer peripheral surface of the first oil inlet section 2.4 and the opening of the second annular groove 1.5 with the outer peripheral surface of the second oil inlet section 2.2, the oil grooves 2.8.1.1 on the multiple overlapping first sector portions 2.8.1 in each first stator lamination of the first oil inlet section 2.4 can be used to form the first oil inlet end 2.6.2 of each first oil passage 2.7, and the oil grooves 2.8.1.1 on the multiple overlapping first sector portions 2.8.1 in each first stator lamination of the second oil inlet section 2.2 can be used to form the second oil inlet end 2.7.2 of each second oil passage 2.7, thus ensuring that all first oil inlet ends 2.6.2 are connected to the first annular groove 1.4 and all second oil inlet ends 2.7.2 are connected to the second annular groove 1.5.

[0086] It should be noted that, for the sake of simplifying the illustrations, Figure 8 The positioning shoulder 1.6 is not shown in the figure.

[0087] Specifically, in this embodiment, such as Figure 1 , Figure 9 , Figure 10 and Figure 11 As shown, multiple weld groove groups are provided on the outer circumferential surface of the stator core 2; each weld groove group is evenly distributed along its circumference on the stator core 2; The weld pool group includes a first weld pool 2.10 and a second weld pool 2.11 arranged circumferentially along the stator core 2; both the first weld pool 2.10 and the second weld pool 2.11 extend axially along the stator core 2. The first weld groove 2.10 is located in the first oil outlet section 2.1, and one end of the first weld groove 2.10 extends to the end face of the first end. One end of the second weld groove 2.11 extends to the first oil outlet section 2.1 and is closed; the other end of the second weld groove 2.11 extends to the end face of the second end; the minimum distance between the end of the second weld groove 2.11 near the first end and the first end is less than the length of the first weld groove 2.10 in the axial direction of the stator core 2; An inwardly protruding positioning shoulder 1.6 is provided on the inner circumferential surface of the motor housing 1; the positioning shoulder 1.6 is used to fit against the second end to complete the positioning of the stator core 2 inside the motor housing 1; The projections of each second weld groove 2.11 on the radial section of the stator core 2 are all within the projection of the positioning shoulder 1.6 on the radial section; The projection of the second oil outlet end 2.7.1 of each second oil passage 2.7 on the radial section is outside the projection of the positioning shoulder 1.6 on the radial section.

[0088] Because existing stator cores are typically composed of hundreds or thousands of individual silicon steel laminations firmly stacked together, laser welding is a commonly used method to firmly bond these laminations into a robust and compact core. To facilitate laser welding, weld grooves are pre-designed in the lamination design. After the laminations are stacked, these grooves connect to form weld beads for subsequent welding. However, the presence of weld beads often leads to oil leakage from the weld grooves. Cooling oil flows through the weld beads to both ends of the stator, failing to cool the stator core according to the pre-designed cooling flow path. This results in the actual cooling flow rate being lower than the design value, reducing the cooling effect.

[0089] The bidirectional oil-cooled motor stator heat dissipation structure provided by this invention ensures full axial coverage of the weld grooves on the stator core 2 by placing the first weld groove 2.10 at the first oil outlet section 2.1, with one end of the first weld groove 2.10 extending to the end face of the first end; and placing one end of the second weld groove 2.11 at the first oil outlet section 2.1 and enclosed therein, with the other end of the second weld groove 2.11 extending to the end face of the second end; and ensuring that the minimum distance between the end of the second weld groove 2.11 closest to the first end and the first end is less than the axial length of the first weld groove 2.10 on the stator core 2. Furthermore, since none of the first weld grooves 2.10 connect to the first annular groove 1.4, this ensures complete axial coverage of the weld grooves on the stator core 2. The second annular groove 1.5 ensures that the first weld groove 2.10 will not leak cooling oil; although the second weld groove 2.11 connects the first annular groove 1.4 and the second annular groove 1.5, the projection of the second weld groove 2.11 on the radial section of the stator core 2 is within the projection of the positioning shoulder 1.6 on the radial section. The positioning shoulder 1.6 can cover and close the openings of the second weld groove 2.11 on the end face of the second end, ensuring that the second weld groove 2.11 will not leak cooling oil. Therefore, the bidirectional oil-cooled motor stator heat dissipation structure provided by the present invention will not have the problem of oil leakage in the first weld groove 2.10 and the second weld groove 2.11.

[0090] It should be noted that, in Figure 11 In the diagram, the area between the two blue lines on the left is the projection of the first annular groove 1.4 onto the outer circumferential surface of the stator core 2, and the area between the two blue lines on the right is the projection of the second annular groove 1.5 onto the outer circumferential surface of the stator core 2; the gray area on the far right (extending along the vertical direction in the diagram) is the projection of the positioning shoulder 1.6 onto the outer side of the second end of the stator core 2.

[0091] Specifically, in this embodiment, such as Figures 9 to 11 As shown, a plurality of first connecting groove groups are formed on the outer peripheral surface of the first stator lamination, and each first connecting groove group is evenly distributed along the circumferential direction of the first stator lamination. Multiple second connecting groove groups are formed on the outer peripheral surface of the second stator lamination, and each second connecting groove group is evenly distributed along the circumferential direction of the second stator lamination; The number of first connecting slot groups on the first stator lamination is the same as the number of second connecting slot groups on the second stator lamination; The first connecting groove group includes a first connecting groove 2.8.1.3 formed on the outer arc surface of the first sector portion 2.8.1 of a certain first sector group 2.8, and a second connecting groove 2.8.2.3 formed on the outer arc surface of the second sector portion 2.8.2 of the same first sector group 2.8; The first connecting groove 2.8.1.3 and the second connecting groove 2.8.2.3 both extend along the axial direction of the first stator lamination. The central axis of the first connecting groove 2.8.1.3 intersects the axis of symmetry of the first sector 2.8.1, and the central axis of the second connecting groove 2.8.2.3 intersects the axis of symmetry of the second sector 2.8.2. The second connecting groove group includes a third connecting groove 2.9.1.2 formed on the outer arc surface of the third sector portion 2.9.1 of a certain second sector group 2.9, and a fourth connecting groove 2.9.2.2 formed on the outer arc surface of the fourth sector portion 2.9.2 of the same second sector group 2.9; The third connecting groove 2.9.1.2 and the fourth connecting groove 2.9.2.2 both extend along the axial direction of the second stator lamination. The central axis of the third connecting groove 2.9.1.2 intersects the axis of symmetry of the third sector 2.9.1, and the central axis of the fourth connecting groove 2.9.2.2 intersects the axis of symmetry of the fourth sector 2.9.2. The number of first sector groups 2.8 on the first stator lamination is an integer multiple of the number of first connecting groove groups, and the multiple is not less than two. The first connecting groove 2.8.1.3, the second connecting groove 2.8.2.3, the third connecting groove 2.9.1.2, and the fourth connecting groove 2.9.2.2 are used to cooperate with each other to form each first weld groove 2.10 and each second weld groove 2.11.

[0092] By evenly distributing the first connecting slot groups along the circumference of the first stator laminations and the second connecting slot groups along the circumference of the second stator laminations, with the number of first connecting slot groups on the first stator laminations being the same as the number of second connecting slot groups on the second stator laminations, and the number of first sector groups 2.8 on the first stator laminations being an integer multiple of the number of first connecting slot groups, and the multiple being not less than two, the stator core 2 can be formed by deflecting and staggering the first and second stator laminations in units of the central angle of the sector portions (first sector portion 2.8.1, second sector portion 2.8.2, third sector portion 2.9.1, or fourth sector portion 2.9.2). Simultaneously, the overlapping of different sector portions... In the stator core 2, the first oil passage, the second oil passage, and the third oil passage cooperate to form each first oil passage 2.6 and each second oil passage 2.7. At the same time, the first connecting groove 2.8.1.3, the second connecting groove 2.8.2.3, the third connecting groove 2.9.1.2, and the fourth connecting groove 2.9.2.2 cooperate to form each first welding groove 2.10, each second welding groove 2.11, and several redundant groove segments 2.13. It is ensured that these redundant groove segments 2.13 will not connect the annular groove (i.e., the first annular groove 1.4 and / or the second annular groove 1.5) with the end face of the stator core 2 (i.e., the end face of the first end and / or the end face of the second end) to cause oil leakage.

[0093] Specifically, in this embodiment, such as Figure 9 and Figure 10 As shown, the number of first sector groups 2.8 on the first stator lamination is three times the number of first connecting slot groups, and the number of second sector groups 2.9 on the second stator lamination is three times the number of second connecting slot groups.

[0094] Specifically, in this embodiment, such as Figure 9 and Figure 10 As shown, to facilitate the setting of the first connecting slot 2.8.1.3 and the second connecting slot 2.8.2.3, There are two oil grooves 2.8.1.1 in each first oil passage, and two first oil holes 2.8.2.1 in each second oil passage; the two oil grooves 2.8.1.1 on each first sector 2.8.1 are symmetrically arranged on both sides of the first connecting groove 2.8.1.3 on the first sector 2.8.1; the two first oil holes 2.8.2.1 on each second sector 2.8.2 are symmetrically arranged on both sides of the second connecting groove 2.8.2.3 on the second sector 2.8.2.

[0095] The bidirectional oil-cooled motor stator heat dissipation structure provided in the above embodiments has at least the following technical effects or advantages: 1. By setting up each first oil passage 2.6 and each second oil passage 2.7, the bidirectional oil-cooled motor stator heat dissipation structure provided by the present invention not only forms multiple oil passages (including each first oil passage 2.6 and each second oil passage 2.7) arranged circumferentially on the stator core 2, but also enables any two adjacent oil passages to independently transport cooling oil in the opposite direction along the axial direction of the stator core 2 (that is, the first oil passage 2.6 transports cooling oil from the second end of the stator core 2 to the first end and then flows out from the end face of the first end; the second oil passage 2.7 transports cooling oil from the first end of the stator core 2 to the second end and then flows out from the end face of the second end). By setting up bidirectional oil passages, the cooling uniformity of the stator core 2 can be improved as much as possible, solving the technical problem of the existing oil-cooled motor stator structure having a single flow direction of cooling oil in the axial direction of the stator core 2 and uneven cooling of the stator core 2.

[0096] 2. Due to the trend towards lightweighting and miniaturization of electric drive systems, the design size of the oil flow channels in existing motor stator oil-cooling structures is usually small. This results in the cooling oil in existing motor stator oil-cooling structures typically being in a laminar flow state within the oil flow channels, with the boundary layer thickness gradually increasing along the flow direction, further exacerbating the problem of weakened heat exchange in the downstream region. However, by ensuring that the minimum distance between any two adjacent first flow channels 2.6.3 and the central axis of the stator core 2 is different, and the minimum distance between any two adjacent second flow channels 2.7.3 and the central axis is also different, the bidirectional oil-cooled motor stator heat dissipation structure provided by this invention ensures that the first oil passage 2.6 and the second oil passage 2.7 are both stepped flow channels along the cooling oil flow direction. The presence of the stepped structure can create turbulence, thereby disrupting or weakening the growth of the boundary layer, improving the problem of weakened heat exchange in the downstream region, increasing the heat exchange area, and enhancing the convective heat exchange effect of the cooling oil within the oil flow channels.

[0097] 3. By dividing the first stator laminations into first sector 2.8.1 and second sector 2.8.2, and the second stator laminations into third sector 2.9.1 and fourth sector 2.9.2, and by opening a first oil channel on the first sector 2.8.1, a second oil channel on the second sector 2.8.2, and a third oil channel on the second sector 2.9, the stator core 2 can be formed by deflecting and stacking the first and second stator laminations in a staggered manner with the central angle of the sector (first sector 2.8.1, second sector 2.8.2, third sector 2.9.1 or fourth sector 2.9.2) as the unit. At the same time, by overlapping and bonding the different sector 2, first oil channels 2.6 and second oil channels 2.7 are formed on the stator core 2.

[0098] 4. By covering the opening of the first annular groove 1.4 with the outer peripheral surface of the first oil inlet section 2.4 and the opening of the second annular groove 1.5 with the outer peripheral surface of the second oil inlet section 2.2, the oil grooves 2.8.1.1 on the multiple overlapping first sector portions 2.8.1 in each first stator lamination of the first oil inlet section 2.4 can be used to form the first oil inlet end 2.6.2 of each first oil passage 2.6, and the oil grooves 2.8.1.1 on the multiple overlapping first sector portions 2.8.1 in each first stator lamination of the second oil inlet section 2.2 can be used to form the second oil inlet end 2.7.2 of each second oil passage 2.7, thus ensuring that all first oil inlet ends 2.6.2 are connected to the first annular groove 1.4 and all second oil inlet ends 2.7.2 are connected to the second annular groove 1.5.

[0099] 5. Since existing stator cores 2 are typically composed of hundreds or thousands of individual silicon steel laminations firmly stacked together, laser welding is a commonly used method to firmly bond these laminations into a robust and compact core. To facilitate laser welding, weld grooves are pre-designed in the lamination design. After the laminations are stacked, these grooves connect to form weld beads for subsequent welding. However, the presence of weld beads often leads to oil leakage from the weld grooves. Cooling oil flows through the weld beads to both ends of the stator, failing to cool the stator core 2 according to the pre-designed cooling flow path. This results in the actual cooling flow rate being lower than the design value, reducing the cooling effect.

[0100] 6. The bidirectional oil-cooled motor stator heat dissipation structure provided by the present invention ensures full axial coverage of the weld grooves in the stator core 2 by placing the first weld groove 2.10 at the first oil outlet section 2.1, with one end of the first weld groove 2.10 extending to the end face of the first end; and placing one end of the second weld groove 2.11 at the first oil outlet section 2.1 and enclosing it, with the other end of the second weld groove 2.11 extending to the end face of the second end; and ensuring that the minimum distance between the end of the second weld groove 2.11 near the first end and the first end is less than the length of the first weld groove 2.10 in the axial direction of the stator core 2. Furthermore, since none of the first weld grooves 2.10 connect to the first annular groove 1. The first weld groove 2.10 and the second annular groove 1.5 ensure that the first weld groove 2.10 will not leak cooling oil. Although the second weld groove 2.11 connects the first annular groove 1.4 and the second annular groove 1.5, the projection of the second weld groove 2.11 on the radial section of the stator core 2 is within the projection of the positioning shoulder 1.6 on the radial section. The positioning shoulder 1.6 can cover and close the opening on the end face of the second weld groove 2.11 at the second end, ensuring that the second weld groove 2.11 will not leak cooling oil. Therefore, the first weld groove 2.10 and the second weld groove 2.11 in the bidirectional oil-cooled motor stator heat dissipation structure provided by the present invention will not have the problem of oil leakage.

[0101] 7. By evenly distributing each first connecting slot group along the circumference of the first stator lamination and each second connecting slot group along the circumference of the second stator lamination, the number of first connecting slot groups on the first stator lamination is the same as the number of second connecting slot groups on the second stator lamination, and the number of first sector groups 2.8 on the first stator lamination is an integer multiple of the number of first connecting slot groups, and the multiple is not less than two; thus, by using each first stator lamination and each second stator lamination, with the central angle of the sector (first sector 2.8.1, second sector 2.8.2, third sector 2.9.1 or fourth sector 2.9.2) as the unit, the stator core 2 is formed by deflection and staggered stacking, while simultaneously using the overlap between different sector groups... The stator core 2 is laminated with oil channels. The first oil channel, the second oil channel and the third oil channel cooperate to form the first oil passage 2.6 and the second oil passage 2.7. At the same time, the stator core 2 is also laminated with the first connecting groove 2.8.1.3, the second connecting groove 2.8.2.3, the third connecting groove 2.9.1.2 and the fourth connecting groove 2.9.2.2 cooperate to form the first welding groove 2.10, the second welding groove 2.11 and a number of redundant groove segments 2.13. It is ensured that these redundant groove segments 2.13 will not connect the annular groove (i.e. the first annular groove 1.4 and / or the second annular groove 1.5) with the end face of the stator core 2 (i.e. the end face of the first end and / or the end face of the second end) to avoid oil leakage.

[0102] The above are merely specific application examples of the present invention and do not constitute any limitation on the scope of protection of the present invention. All technical solutions formed by equivalent transformation or equivalent substitution fall within the scope of protection of the present invention.

Claims

1. A bidirectional oil-cooled motor stator heat dissipation structure, characterized in that, include: The motor housing and the stator core installed inside the motor housing; the outer peripheral surface of the stator core is interference-fitted with the inner peripheral surface of the motor housing; The stator core is divided into a first oil outlet section, a second oil inlet section, a main body section, and a second oil outlet section along its axial direction from its first end to its second end. The stator core is provided with a plurality of oil passage units spaced apart along the circumference. Each oil passage unit includes a first oil passage and a second oil passage. The first oil passage and the second oil passage are arranged spaced apart along the circumference of the stator core. Both the first oil passage and the second oil passage extend axially on the stator core. The first oil outlet of the first oil passage extends to the end face of the first end, and the first oil inlet of the first oil passage extends to the outer peripheral surface of the first oil inlet section; The second oil outlet of the second oil passage extends to the end face of the second end, and the second oil inlet of the second oil passage extends to the outer peripheral surface of the second oil inlet section; The motor housing has an oil delivery passage with one oil inlet and two oil outlets. The oil inlet is located on the outer surface of the motor housing, and the two oil outlets are located on the inner circumferential surface of the motor housing. One of the oil outlets is connected to all the first oil inlets, and the other oil outlet is connected to all the second oil inlets.

2. The bidirectional oil-cooled motor stator heat dissipation structure according to claim 1, characterized in that: The first oil passage is divided into a plurality of sequentially connected first flow channels along the axial direction of the stator core, and the second oil passage is divided into a plurality of sequentially connected second flow channels along the axial direction of the stator core; each first flow channel and each second flow channel extends along the axial direction of the stator core. The minimum distance between any two adjacent first flow channels and the central axis of the stator core is different; the minimum distance between any two adjacent second flow channels and the central axis is also different.

3. The bidirectional oil-cooled motor stator heat dissipation structure according to claim 1, characterized in that: The stator core is composed of multiple first stator laminations and multiple second stator laminations stacked together; The first stator lamination is divided into multiple first sector groups along the circumferential direction, and the first sector group is divided into a first sector portion and a second sector portion along the circumferential direction. A second sector portion is provided between any two adjacent first sector portions. The second stator lamination is divided into multiple second sector groups along the circumferential direction, and the second sector group is divided into third sector portions and fourth sector portions along the circumferential direction. A fourth sector portion is provided between any two adjacent third sector portions. The central angles of the first sector, the second sector, the third sector, and the fourth sector are equal; The first sector has a first oil passage, the second sector has a second oil passage, and the second sector group has a third oil passage; The first oil passage includes an oil groove formed on the outer arc surface of the first sector portion, the oil groove extending along the axial direction of the first sector portion and penetrating the first sector portion; The second oil passage includes a first oil hole formed on the side of the second sector portion, the first oil hole extending along the axial direction of the second sector portion and penetrating the second sector portion; The third oil passage includes a second oil hole formed on the side of the third sector, the second oil hole extending along the axial direction of the third sector and penetrating the third sector; The oil groove on the first sector portion is connected to the first oil hole on the second sector portion that overlaps and fits with the first sector portion; The first oil hole on the second sector and the second oil hole on the third sector that overlaps and fits with the second sector are connected; When the first sector and the fourth sector overlap and fit together, the fourth sector blocks the end of the oil groove on the first sector that faces the fourth sector. The first oil passage, the second oil passage, and the third oil passage are used to cooperate with each other to form each of the first oil passage and each of the second oil passage.

4. The bidirectional oil-cooled motor stator heat dissipation structure according to claim 3, characterized in that: Both the first oil outlet section and the second oil outlet section are composed of multiple stacked second stator laminations; the second oil inlet section, the main body section, and the first oil inlet section are all composed of multiple stacked first stator laminations.

5. The bidirectional oil-cooled motor stator heat dissipation structure according to claim 4, characterized in that: The projections of the third sector on any second stator lamination in the first oil outlet section onto the radial section of the stator core, the projections of the second sector on any first stator lamination in the second oil inlet section onto the radial section, the projections of the first sector on any first stator lamination in the first oil inlet section onto the radial section, and the projections of the fourth sector on any second stator lamination in the second oil outlet section all coincide. Each of the oil troughs on the first oil inlet section is connected to one of the oil outlets, and each of the oil troughs on the second oil inlet section is connected to the other oil outlet.

6. The bidirectional oil-cooled motor stator heat dissipation structure according to claim 5, characterized in that: The main body segment is divided into multiple main body sub-segments along its axial direction; Each of the aforementioned main body sub-segments is formed by stacking multiple first stator laminations; The projection of each first sector on any first stator lamination in any main body sub-segment onto the radial section coincides with the projection of each second sector on any first stator lamination in the adjacent main body sub-segment onto the radial section.

7. The bidirectional oil-cooled motor stator heat dissipation structure according to claim 6, characterized in that: The projection of each second sector on the radial section of any first stator lamination in the main body sub-segment closest to the second oil inlet section coincides with the projection of each first sector on the radial section of any first stator lamination in the second oil inlet section. The projection of each second sector on the radial section of any first stator lamination in the main body sub-segment closest to the first oil inlet section coincides with the projection of each first sector on the radial section of any first stator lamination in the first oil inlet section.

8. The bidirectional oil-cooled motor stator heat dissipation structure according to claim 7, characterized in that: The first minimum distance between the oil groove and the central axis of the stator core is greater than the second minimum distance between the first oil hole and the central axis. The second minimum distance value is greater than the third minimum distance value between the second oil hole and the central axis.

9. The bidirectional oil-cooled motor stator heat dissipation structure according to claim 3, characterized in that: The third oil passage also includes a third oil hole formed on the side of the fourth sector, the third oil hole extending along the axial direction of the fourth sector and penetrating the fourth sector; The second oil hole on the third sector is connected to the third oil hole on the fourth sector that overlaps and fits with the third sector; The oil groove on the first sector and the third oil hole on the fourth sector, which overlaps and fits with the first sector, are misaligned and isolated; The first minimum distance between the oil groove and the central axis of the stator core is greater than the second minimum distance between the first oil hole and the central axis. The second minimum distance value is greater than the third minimum distance value between the second oil hole and the central axis; The third minimum distance value is greater than the fourth minimum distance value between the third oil hole and the central axis.

10. The bidirectional oil-cooled motor stator heat dissipation structure according to claim 9, characterized in that: The second oil inlet section, the main body section, and the first oil inlet section are all formed by stacking multiple first stator laminations; the first oil outlet section and the second oil outlet section are both formed by stacking multiple second stator laminations.

11. The bidirectional oil-cooled motor stator heat dissipation structure according to claim 10, characterized in that: The first oil outlet section is divided into a first segment and a second segment along its axial direction. The first segment is located on the side away from the second oil inlet section, and the second segment is located on the side close to the second oil inlet section. The second oil outlet section is divided into a third section and a fourth section along its axial direction. The third section is located on the side away from the first oil inlet section, and the fourth section is located on the side close to the first oil inlet section. The first segment, the second segment, the third segment, and the fourth segment are all composed of multiple second stator laminations stacked together; The projections of the fourth sector on any second stator lamination in the first segment onto the radial section of the stator core, the projections of the third sector on any second stator lamination in the second segment onto the radial section, the projections of the second sector on any first stator lamination in the second oil inlet segment onto the radial section, the projections of the first sector on any first stator lamination in the first oil inlet segment onto the radial section, the projections of the fourth sector on any second stator lamination in the fourth segment onto the radial section, and the projections of the third sector on any second stator lamination in the third segment all coincide.

12. The bidirectional oil-cooled motor stator heat dissipation structure according to claim 9, characterized in that: The first oil passage further includes a fourth oil hole formed on the side of the first sector portion, the fourth oil hole extending along the axial direction of the first sector portion and penetrating the first sector portion; The fourth oil hole on the first sector and the first oil hole on the second sector that overlaps and fits with the first sector are misaligned and isolated; The fourth oil hole on the first sector is connected to the third oil hole on the fourth sector that overlaps and fits with the first sector; The fourth minimum distance value is greater than the fifth minimum distance value between the fourth oil hole and the central axis.

13. The bidirectional oil-cooled motor stator heat dissipation structure according to claim 12, characterized in that: The second oil inlet section, the main body section, and the first oil inlet section are all formed by stacking multiple first stator laminations; the first oil outlet section and the second oil outlet section are both formed by stacking multiple first stator laminations and multiple second stator laminations.

14. The bidirectional oil-cooled motor stator heat dissipation structure according to claim 13, characterized in that: The first oil outlet section is divided into a fifth section, a sixth section and a seventh section along its axial direction, and the seventh section is in contact with the second oil inlet section; The second oil outlet section is divided into the eighth, ninth and tenth sections along its axial direction, and the tenth section is in contact with the first oil inlet section; The sixth segment, the seventh segment, the ninth segment, and the tenth segment are all formed by stacking multiple second stator laminations; the fifth segment and the eighth segment are all formed by stacking multiple first stator laminations. The projections of the first sector on any first stator lamination in the fifth segment onto the radial section of the stator core, the projections of the fourth sector on any second stator lamination in the sixth segment onto the radial section, the projections of the third sector on any second stator lamination in the seventh segment onto the radial section, the projections of the second sector on any first stator lamination in the second oil inlet segment onto the radial section, the projections of the first sector on any first stator lamination in the first oil inlet segment onto the radial section, the projections of the fourth sector on any second stator lamination in the tenth segment onto the radial section, the projections of the third sector on any second stator lamination in the ninth segment onto the radial section, and the projections of the second sector on any first stator lamination in the eighth segment all coincide.

15. The bidirectional oil-cooled motor stator heat dissipation structure according to claim 12, characterized in that: The second oil passage also includes a fifth oil hole formed on the side of the second sector portion, the fifth oil hole extending along the axial direction of the second sector portion and penetrating the second sector portion; The fourth oil hole on the first sector and the fifth oil hole on the second sector that overlaps and fits with the first sector are connected; The oil groove on the first sector and the fifth oil hole on the second sector that overlaps and fits with the first sector are misaligned and isolated; The fifth oil hole on the second sector and the second oil hole on the third sector that overlaps and fits with the second sector are misaligned and isolated; The fifth minimum distance value is greater than the sixth minimum distance value between the fifth oil hole and the central axis.

16. The bidirectional oil-cooled motor stator heat dissipation structure according to claim 15, characterized in that: The second oil inlet section, the main body section, and the first oil inlet section are all formed by stacking multiple first stator laminations; the first oil outlet section and the second oil outlet section are both formed by stacking multiple first stator laminations and multiple second stator laminations.

17. The bidirectional oil-cooled motor stator heat dissipation structure according to claim 16, characterized in that: The first oil outlet section is divided into eleventh, twelfth, thirteenth and fourteenth sections along its axial direction, and the fourteenth section is in contact with the second oil inlet section; The second oil outlet section is divided into the fifteenth, sixteenth, seventeenth and eighteenth sections along its axial direction, and the eighteenth section is in contact with the first oil inlet section; The thirteenth, fourteenth, seventeenth, and eighteenth segments are all formed by stacking multiple second stator laminations; the eleventh, twelfth, fifteenth, and sixteenth segments are all formed by stacking multiple first stator laminations. The projections of the second sector portions on any first stator lamination in the eleventh segment onto the radial section of the stator core, the projections of the first sector portions on any first stator lamination in the twelfth segment onto the radial section, the projections of the fourth sector portions on any second stator lamination in the thirteenth segment onto the radial section, the projections of the third sector portions on any second stator lamination in the fourteenth segment onto the radial section, and the projections of the second sector portions on any first stator lamination in the second oil inlet section onto the radial section. The projections of each first sector on any first stator lamination in the first oil inlet section, each fourth sector on any second stator lamination in the eighteenth segment, each third sector on any second stator lamination in the seventeenth segment, each second sector on any first stator lamination in the sixteenth segment, and each first sector on any first stator lamination in the fifteenth segment all coincide on the radial section.

18. The bidirectional oil-cooled motor stator heat dissipation structure according to claim 3, characterized in that: The oil delivery circuit includes a cooling oil passage formed in the motor housing, an oil inlet formed on the outer surface of the motor housing, and a first annular groove and a second annular groove formed on the inner circumferential surface of the motor housing. Both the first annular groove and the second annular groove extend circumferentially along the motor housing; The first annular groove is provided corresponding to the first oil inlet section, and the second annular groove is provided corresponding to the second oil inlet section; The outer peripheral surface of the first oil inlet section covers the opening of the first annular groove, and the outer peripheral surface of the second oil inlet section covers the opening of the second annular groove; The two oil outlets of the oil conveying circuit are the first annular groove and the second annular groove, respectively. All of the first oil inlet ends are connected to the first annular groove, and all of the second oil inlet ends are connected to the second annular groove.

19. The bidirectional oil-cooled motor stator heat dissipation structure according to claim 18, characterized in that: Multiple weld groove groups are provided on the outer circumferential surface of the stator core; each weld groove group is evenly distributed along its circumference on the stator core. The weld groove group includes a first weld groove and a second weld groove that are spaced apart circumferentially along the stator core; both the first weld groove and the second weld groove extend axially along the stator core. The first weld groove is located in the first oil outlet section, and one end of the first weld groove extends to the end face of the first end. One end of the second weld groove extends to the first oil outlet section and is closed; the other end of the second weld groove extends to the end face of the second end; the minimum distance between the end of the second weld groove near the first end and the first end is less than the length of the first weld groove in the axial direction of the stator core. The inner circumferential surface of the motor housing is provided with an inwardly protruding positioning shoulder; the positioning shoulder is used to fit against the second end to complete the positioning of the stator core within the motor housing; The projections of each of the second weld grooves on the radial section of the stator core are all within the projection of the positioning shoulder on the radial section; The projection of the second oil outlet end of each of the second oil passages onto the radial section is outside the projection of the positioning shoulder onto the radial section.

20. The bidirectional oil-cooled motor stator heat dissipation structure according to claim 19, characterized in that: A plurality of first connecting groove groups are formed on the outer peripheral surface of the first stator lamination, and each first connecting groove group is evenly distributed along the circumferential direction of the first stator lamination; A plurality of second connecting groove groups are formed on the outer peripheral surface of the second stator lamination, and each second connecting groove group is evenly distributed along the circumferential direction of the second stator lamination; The number of first connecting slot groups on the first stator lamination is the same as the number of second connecting slot groups on the second stator lamination; The first connecting groove group includes a first connecting groove formed on the outer arc surface of the first sector portion of a certain first sector group, and a second connecting groove formed on the outer arc surface of the second sector portion of the same first sector group. Both the first connecting groove and the second connecting groove extend along the axial direction of the first stator lamination. The central axis of the first connecting groove intersects the axis of symmetry of the first sector, and the central axis of the second connecting groove intersects the axis of symmetry of the second sector. The second connecting groove group includes a third connecting groove formed on the outer arc surface of the third sector of a certain second sector group, and a fourth connecting groove formed on the outer arc surface of the fourth sector of the same second sector group. Both the third connecting groove and the fourth connecting groove extend along the axial direction of the second stator lamination. The central axis of the third connecting groove intersects the axis of symmetry of the third sector, and the central axis of the fourth connecting groove intersects the axis of symmetry of the fourth sector. The number of first sector groups on the first stator lamination is an integer multiple of the number of first connecting groove groups, and the multiple is not less than two. The first connecting groove, the second connecting groove, the third connecting groove, and the fourth connecting groove are used to cooperate with each other to form each first weld groove and each second weld groove.

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