Oil cooling system and electric drive system

Abstract

The invention discloses an oil cooling system, including an oil pump, an oil cooler, a reducer oil cooling circuit and a motor oil cooling circuit. The oil pump and the oil cooler are installed on the reducer housing. The oil pump delivers the oil at the bottom of the reducer housing to the oil cooler. The oil cooler is used to connect with the water cooling system of the vehicle and cool the oil. The oil cooler delivers the cooled oil to the reducer oil cooling circuit; the reducer oil cooling circuit includes an oil cooling inlet, an oil cooling outlet, an input shaft branch, and an output shaft branch. The oil cooling inlet is connected to the inlet of the oil cooler, the oil cooling outlet is connected to the outlet of the oil cooler, and the oil cooling outlet is also connected to the input shaft branch and the output shaft branch; the motor oil cooling circuit includes a motor shaft main circuit and a rotor core oil circuit. The input shaft branch is connected to the motor shaft main circuit, and the motor shaft main circuit is connected to multiple rotor core oil circuits. The invention also discloses an electric drive system. The invention has the advantages of high cooling efficiency, reasonable oil circuit layout, and more compact structure.

Description

Technical Field

[0001] The present invention relates to the technical field of electric drive systems, and in particular to an oil cooling system and an electric drive system. Background Art

[0002] As an important part of electric vehicle cooling technology, the oil cooling system of the electric drive system is usually used to cool the motor and reducer. Existing oil cooling systems usually use oil spray or oil immersion cooling methods, and pump lubricating oil into the motor through an oil pump to achieve effective cooling of the motor. Existing reducer oil cooling usually uses splash-type passive cooling, which drives the oil at the bottom of the reducer housing through the gears and splashes the oil to the gears and bearings for cooling.

[0003] The existing oil cooling system passively cools the reducer, and the oil cannot reach every part of the reducer evenly, and the cooling effect on some parts of the reducer is insufficient. In addition, the utilization rate of the oil cooling system of the existing electric drive system is not high, and the reducer and motor are cooled separately. Some designs share the oil cooling system of the reducer and motor, but require external pipes for connection, which increases the volume of the electric drive system and occupies a large space.

[0004] Therefore, it is necessary to design an oil cooling system and electric drive system with high cooling efficiency, reasonable oil circuit layout and more compact structure. Summary of the invention

[0005] The purpose of the present invention is to overcome the deficiencies of the prior art and to provide an oil cooling system and an electric drive system with high cooling efficiency, reasonable oil circuit layout and more compact structure.

[0006] The technical solution of the present invention provides an oil cooling system, comprising an oil pump, an oil cooler, a reducer oil cooling circuit and a motor oil cooling circuit, wherein the reducer oil cooling circuit is arranged in the reducer housing, the motor oil cooling circuit is arranged in the motor, the oil pump and the oil cooler are installed on the reducer housing, the oil pump transports the oil at the bottom of the reducer housing to the oil cooler, the oil cooler is used to be connected to the water cooling system of the vehicle and cool the oil, and the oil cooler transports the cooled oil to the reducer oil cooling circuit;

[0007] The reducer oil cooling circuit includes an oil cooling inlet, an oil cooling outlet, an input shaft branch, and an output shaft branch. The oil cooling inlet is connected to the inlet of the oil cooler, the oil cooling outlet is connected to the outlet of the oil cooler, and the oil cooling outlet is also connected to the input shaft branch and the output shaft branch.

[0008] The motor oil cooling circuit includes a motor shaft main line and a rotor core oil line, the input shaft branch is connected to the motor shaft main line, and the motor shaft main line is connected to a plurality of rotor core oil lines.

[0009] Furthermore, an input shaft is connected between the motor and the reducer housing;

[0010] The input shaft branch includes a first pipeline, a second pipeline and a first oil nozzle, the first pipeline is arranged inside the side wall of the reducer housing, the oil cooling outlet is connected to the first pipeline, the first oil nozzle is arranged at the center of the input shaft mounting position of the reducer housing, the second pipeline is arranged inside the reducer housing, one end of the second pipeline is connected to the first pipeline, and the other end is connected to the first oil nozzle, the first oil nozzle is connected to the central through hole of the input shaft, and the central through hole is connected to the motor shaft main pipeline.

[0011] Further, the output shaft branch includes a third pipeline and a fourth pipeline, the third pipeline extends obliquely upward from the first pipeline to above the intermediate shaft mounting position of the reducer housing, one end of the fourth pipeline is connected to the third pipeline, and the other end extends to above the output shaft mounting position of the reducer housing, and a first oil hole and a second oil hole are opened on the fourth pipeline, the first oil hole leads to the intermediate shaft mounting position, and the second oil hole leads to the output shaft mounting position.

[0012] Furthermore, the reducer oil cooling circuit also includes a second oil nozzle, the second oil nozzle is connected to the fourth pipeline, and the second oil nozzle extends to the input shaft installation position of the reducer housing.

[0013] Furthermore, the reducer oil cooling circuit also includes a reducer cover branch, the reducer cover branch is arranged inside the reducer cover, and the first pipeline is connected to the reducer cover branch.

[0014] Furthermore, the reducer cover plate includes an input bearing mounting position, an intermediate bearing mounting position and an output bearing mounting position;

[0015] The reducer cover branch includes a third oil nozzle, a fifth pipeline, a sixth pipeline and a seventh pipeline. The third oil nozzle is connected to the end of the first pipeline. The fifth pipeline is arranged above the input bearing mounting position and the intermediate bearing mounting position. One end of the fifth pipeline is connected to the third oil nozzle. A third oil hole is opened on the fifth pipeline, and the third oil hole leads to the input bearing mounting position. One end of the sixth pipeline is connected to the fifth pipeline, and the other end is connected to the intermediate bearing mounting position. The seventh pipeline connects the intermediate bearing mounting position with the output bearing mounting position.

[0016] Furthermore, the rotor core oil circuit includes a first rotor branch, a second rotor branch and a third rotor branch, the first rotor branch connects the weight reduction hole of the rotor core and the inclined hole of the end plate, the second rotor branch connects the inner magnetic steel hole of the rotor core and the axial hole of the end plate, and the third rotor branch connects the outer magnetic steel hole of the rotor core and the radial hole of the end plate.

[0017] The present invention also provides an electric drive system, comprising an electronic control housing, a motor housing and a reducer housing, and also the oil cooling system described in any of the above items, wherein the motor housing comprises an end cover, a main housing and a reducer cover plate, the main housing and the reducer cover plate are integrally formed, and the reducer cover plate is covered on the reducer housing.

[0018] Furthermore, there are two motor housings, which are symmetrically arranged on both sides of the reducer housing. The reducer housing includes a first half shell and a second half shell. There are two sets of reducer oil cooling circuits, which are symmetrically arranged in the first half shell and the second half shell.

[0019] Furthermore, one motor is installed in each of the two motor housings, and there are two sets of motor oil cooling circuits, which are respectively arranged in the two motors.

[0020] After adopting the above technical solution, the following beneficial effects are achieved:

[0021] In the present invention, the reducer oil cooling circuit is connected to the oil pump and the oil cooler, and the reducer oil cooling circuit realizes active cooling of the bearings and gears installed in the reducer housing, so that the cooling effect is better; at the same time, the reducer oil cooling circuit is connected with the motor oil cooling circuit, which improves the cooling efficiency; in addition, the reducer cooling circuit and the motor oil cooling circuit are both arranged inside the electric drive system, and there is no need to add external pipelines, so that the overall structure of the electric drive system is more compact and occupies less space. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The disclosure of the present invention will become more easily understood with reference to the accompanying drawings. It should be understood that these drawings are only for illustrative purposes and are not intended to limit the scope of protection of the present invention. In the drawings:

[0023] Figure 1 is a three-dimensional diagram of an electric drive system in one embodiment of the present invention;

[0024] Figure 2 is a schematic diagram of a reducer housing in one embodiment of the present invention;

[0025] Figure 3 The internal structure of the reducer housing in one embodiment of the present invention is shown in FIG. Figure 1 ;

[0026] Figure 4is a cross-sectional view of a reducer housing in one embodiment of the present invention;

[0027] Figure 5 The internal structure of the reducer housing in one embodiment of the present invention is shown in FIG. Figure 2 ;

[0028] Figure 6 The internal structure of the reducer housing in one embodiment of the present invention is shown in FIG. Figure 3 ;

[0029] Figure 7 The internal structure of the reducer housing in one embodiment of the present invention is shown in FIG. Figure 4 ;

[0030] Figure 8 The internal structure of the reducer cover in one embodiment of the present invention is shown in FIG. Figure 1 ;

[0031] Fig. 9 The internal structure of the reducer cover in one embodiment of the present invention is shown in FIG. Figure 2 ;

[0032] Fig.10 The internal structure of the reducer cover in one embodiment of the present invention is shown in FIG. Figure 3 ;

[0033] Fig.11 is an axial cross-sectional view of an electric drive system in one embodiment of the present invention;

[0034] Fig.12 is an exploded view of a motor in one embodiment of the present invention;

[0035] Fig.13 is a partial exploded view of a motor in one embodiment of the present invention;

[0036] Fig.14 is a schematic diagram of an oil guide plate in one embodiment of the present invention;

[0037] Fig.15 is a cross-sectional view of a motor in one embodiment of the present invention Figure 1 ;

[0038] Fig.16 is a cross-sectional view of a motor in one embodiment of the present invention Figure 2 .

[0039] Reference table of reference numerals:

[0040] Oil pump 1, oil cooler 2;

[0041] Oil cooling inlet 31, oil cooling outlet 32, input shaft branch 33, output shaft branch 34, second oil nozzle 35, reducer cover branch 36, central through hole 37, first pipeline 331, second pipeline 332, first oil nozzle 333, third pipeline 341, fourth pipeline 342, third oil nozzle 361, fifth pipeline 362, sixth pipeline 363, seventh pipeline 364, first oil hole 3421, second oil hole 3422;

[0042] The motor shaft main circuit 41, the first rotor branch circuit 42, the second rotor branch circuit 43, the third rotor branch circuit 44, and the divergent oil hole 411;

[0043] Reducer housing 10: input shaft mounting position 101, intermediate shaft mounting position 102, output shaft mounting position 103, first half shell 104, second half shell 105;

[0044] Motor housing 20: end cover 201, main housing 202, reducer cover plate 203, input bearing mounting position 2031, intermediate bearing mounting position 2032, output bearing mounting position 2033;

[0045] Electronic control housing 30;

[0046] Motor 40: motor shaft 401, rotor core 402, oil guide plate 403, end plate 404, input shaft 405, weight reduction hole 4021, inner magnetic steel hole 4022, outer magnetic steel hole 4023, first oil guide hole 4031, second oil guide hole 4032, third oil guide hole 4033, inclined hole 4041, axial hole 4042, radial hole 4043. DETAILED DESCRIPTION

[0047] The specific implementation of the present invention will be further described below in conjunction with the accompanying drawings.

[0048] It is easy to understand that according to the technical solution of the present invention, without changing the essential spirit of the present invention, a variety of structural modes and implementation modes that can be replaced by those skilled in the art can be replaced with each other. Therefore, the following specific implementation modes and drawings are only exemplary descriptions of the technical solution of the present invention, and should not be regarded as the whole of the present invention or as a limitation or restriction to the technical solution of the invention.

[0049] The directional terms such as up, down, left, right, front, back, front, back, top, bottom, etc. mentioned or may be mentioned in this specification are defined relative to the structures shown in the drawings. They are relative concepts and may change accordingly according to different positions and different usage conditions. Therefore, these or other directional terms should not be interpreted as restrictive terms.

[0050] In some embodiments of the present invention, Figure 1As shown, the oil cooling system includes an oil pump 1, an oil cooler 2, a reducer oil cooling circuit and a motor oil cooling circuit. The reducer oil cooling circuit is arranged in the reducer housing 10, and the motor oil cooling circuit is arranged in the motor. The oil pump 1 and the oil cooler 2 are installed on the reducer housing 10. The oil pump 1 transports the oil at the bottom of the reducer housing 10 to the oil cooler 2. The oil cooler 2 is used to connect with the water cooling system of the vehicle and cool the oil. The oil cooler 2 transports the cooled oil to the reducer oil cooling circuit.

[0051] like Figure 2-Figure 4 As shown, the reducer oil cooling circuit includes an oil cooling inlet 31, an oil cooling outlet 32, an input shaft branch 33, and an output shaft branch 34. The oil cooling inlet 31 is connected to the inlet of the oil cooler 2, the oil cooling outlet 32 ​​is connected to the outlet of the oil cooler 2, and the oil cooling outlet 32 ​​is also connected to the input shaft branch 33 and the output shaft branch 34;

[0052] like Fig.11 As shown, the motor oil cooling circuit includes a motor shaft main line 41 and a rotor core oil line, the input shaft branch 33 is connected to the motor shaft main line 41, and the motor shaft main line 41 is connected to multiple rotor core oil lines.

[0053] Specifically, Figure 1 As shown, an oil pump 1 and an oil cooler 2 are provided on the side of the reducer housing 10. The oil pump 1 is connected to the bottom surface of the reducer housing 10 and can pump the oil at the bottom of the reducer housing 10 into the oil cooler 2. The oil cooler 2 is located above the oil pump 1 and is connected to the water cooling system of the vehicle (not shown). The water cooling system can cool the oil flowing through the oil cooler 2 by heat exchange.

[0054] like Figure 2 As shown, an oil cooling inlet 31 and an oil cooling outlet 32 ​​are provided on the side of the reducer housing 10. The oil cooling inlet 31 is connected to the inlet of the oil cooler 2, and the oil cooling outlet 32 ​​is connected to the outlet of the oil cooler 2. The oil cooling inlet 31 is connected to the oil pump 1, and the oil enters the oil cooling inlet 31 from the oil pump 1, and then flows into the oil cooler 2 from the oil cooling inlet 31. The oil cooled by the oil cooler 2 flows into the oil cooling outlet 32.

[0055] like Figure 3 As shown, the input shaft branch 33 is arranged in the reducer housing 10 , and the oil cooling outlet 32 ​​is communicated with the input shaft branch 33 , bringing the oil into the input shaft installation position 101 of the reducer housing 10 .

[0056] like Figure 4 As shown, the reducer housing 10 is also provided with an output shaft branch 34. Since the output shaft branch 34 is also arranged inside the reducer housing 10, Figure 3 The output shaft branch 34 cannot be clearly seen. Figure 4The cross-sectional view can clearly show the output shaft branch 34, Figure 4 The black straight arrow in the figure indicates the flow direction of the oil. The output shaft branch 34 is connected to the oil cooling outlet 32 ​​to deliver the oil to the intermediate shaft installation position 102 and the output shaft installation position 103.

[0057] like Fig.11 As shown, the input shaft branch 33 is connected to the motor shaft main line 41 , and the oil in the reducer housing 10 can be sent to the motor 40 to cool the motor 40 .

[0058] In this embodiment, the reducer oil cooling circuit is connected to the oil pump 1 and the oil cooler 2. The reducer oil cooling circuit realizes active cooling of the bearings and gears installed in the reducer housing 10, so that the cooling effect is better; at the same time, the reducer oil cooling circuit is connected with the motor oil cooling circuit, which improves the cooling efficiency; in addition, the reducer cooling circuit and the motor oil cooling circuit are both arranged inside the electric drive system, and there is no need to add external pipelines, so that the overall structure of the electric drive system is more compact and occupies less space.

[0059] Furthermore, if Fig.11 As shown, an input shaft 405 is connected between the motor 40 and the reducer housing 10;

[0060] like Figure 2-Figure 5 As shown, the input shaft branch 33 includes a first pipeline 331, a second pipeline 332 and a first oil nozzle 333. The first pipeline 331 is arranged inside the side wall of the reducer housing 10, and the oil cooling outlet 32 ​​is connected to the first pipeline 331. The first oil nozzle 333 is arranged at the center of the input shaft installation position 101 of the reducer housing 10. The second pipeline 332 is arranged inside the reducer housing 10. One end of the second pipeline 332 is connected to the first pipeline 331, and the other end is connected to the first oil nozzle 333. The first oil nozzle 333 is connected to the central through hole 37 of the input shaft 405 (see Fig.11 ) is connected, and the central through hole 37 is connected to the motor shaft main pipeline 41.

[0061] Specifically, Figure 2 As shown, the first pipeline 331 is arranged in a horizontal direction along the side of the reducer housing 10 , and the first pipeline 331 is connected to the oil cooling outlet 32 ​​.

[0062] like Figure 3-Figure 4 As shown, the second pipeline 332 extends from the side of the reducer housing 10 toward the center of the input shaft installation position 101 , one end of the second pipeline 332 is connected to the first pipeline 331 , and the other end is connected to the first oil nozzle 333 .

[0063] like Figure 5 As shown, the first oil nozzle 333 is arranged along the axial direction of the input shaft mounting position 101 and has a conical structure. The first oil nozzle 333 can deliver oil into the motor 40 .

[0064] like Fig.11 As shown, the first oil nozzle 333 is connected to the central through hole 37 of the input shaft 405, and the central through hole 37 is connected to the motor shaft main pipeline 41, so that the oil is sent into the motor 40. When the rotor of the motor 40 rotates, the oil is thrown into the rotor, and then thrown from the rotor into the stator, so as to effectively cool the rotor and the stator.

[0065] Furthermore, if Figure 4-Figure 5 As shown, the output shaft branch 34 includes a third pipeline 341 and a fourth pipeline 342. The third pipeline 341 extends obliquely upward from the first pipeline 331 to above the intermediate shaft mounting position 102 of the reducer housing 10. One end of the fourth pipeline 342 is connected to the third pipeline 341, and the other end extends to above the output shaft mounting position 103 of the reducer housing 10. The fourth pipeline 342 is provided with a first oil hole 3421 and a second oil hole 3422. The first oil hole 3421 leads to the intermediate shaft mounting position 102, and the second oil hole 3422 leads to the output shaft mounting position 103.

[0066] Specifically, Figure 4 As shown, the third pipeline 341 extends obliquely upward from the first pipeline 331 to above the input shaft installation position 101 and the intermediate shaft installation position 102 of the reducer housing 10. Figure 6 As shown, the end of the third pipeline 341 extends out from the top of the reducer housing 10. This arrangement is convenient for drilling the third pipeline 341. In actual application, the hole of the third pipeline 341 located above the reducer housing 10 is blocked to prevent oil leakage.

[0067] like Figure 4 As shown, one end of the fourth pipeline 342 is connected to the third pipeline 341, and the other end extends to the top of the output shaft installation position 103 of the reducer housing 10. Figure 6 As shown, the other end of the fourth pipeline 342 extends out from the other side of the reducer housing 10. This arrangement is convenient for drilling the fourth pipeline 342. In actual application, the hole of the fourth pipeline 342 located outside the reducer housing 10 is blocked to prevent oil leakage.

[0068] like Figure 5 As shown, the fourth pipeline 342 is provided with a first oil hole 3421 and a second oil hole 3422. The first oil hole 3421 leads to the intermediate shaft mounting position 102, and the second oil hole 3422 leads to the output shaft mounting position 103. The first oil hole 3421 cools the intermediate bearing, and the second oil hole 3422 cools the output bearing.

[0069] Furthermore, if Figure 5-Figure 6As shown, the reducer oil cooling circuit further includes a second oil nozzle 35 , which is connected to the fourth pipeline 342 , and the second oil nozzle 35 extends to the input shaft installation position 101 of the reducer housing 10 .

[0070] Specifically, the second oil nozzle 35 can be directly connected to the third pipeline 341 or the fourth pipeline 342, or connected at the intersection of the third pipeline 341 and the fourth pipeline 342. The second oil nozzle 35 extends into the input shaft installation position 101 and corresponds to the position of the input shaft gear, so as to cool the input shaft gear.

[0071] Furthermore, if Fig. 9 As shown, the reducer oil cooling circuit also includes a reducer cover branch 36 , which is disposed inside the reducer cover 203 , and the first pipeline 331 is connected to the reducer cover branch 36 .

[0072] Specifically, the reducer cover plate 203 is used to cover the reducer housing 10 to form a complete cavity for installing the reducer. Bearings need to be installed on the reducer cover plate 203, so each bearing also needs to be cooled. The reducer cover plate branch 36 is arranged inside the reducer cover plate 203.

[0073] like Figure 6 As shown, both ends of the first pipeline 331 on the reducer housing 10 are open, and both ends of the first pipeline 331 are just connected to the reducer cover branch 36 to deliver oil into the reducer cover branch 36.

[0074] Furthermore, if Figure 8-Figure 10 As shown, the reducer cover plate 203 includes an input bearing mounting position 2031, an intermediate bearing mounting position 2032 and an output bearing mounting position 2033;

[0075] The reducer cover branch 36 includes a third oil nozzle 361, a fifth pipeline 362, a sixth pipeline 363 and a seventh pipeline 364. The third oil nozzle 361 is connected to the end of the first pipeline 331. The fifth pipeline 362 is arranged above the input bearing mounting position 2031 and the intermediate bearing mounting position 2032. One end of the fifth pipeline 362 is connected to the third oil nozzle 361. A third oil hole (not shown) is opened on the fifth pipeline 362, and the third oil hole leads to the input bearing mounting position 2031. One end of the sixth pipeline 363 is connected to the fifth pipeline 362, and the other end is connected to the intermediate bearing mounting position 2032. The seventh pipeline 364 connects the intermediate bearing mounting position 2032 with the output bearing mounting position 2033.

[0076] Specifically, Figure 8As shown, the third oil nozzle 361 is connected to the fifth pipeline 362, and the fifth pipeline 362 is arranged inside the reducer cover plate 203 and above the input bearing installation position 2031 and the intermediate bearing installation position 2032, so as to facilitate oil supply from top to bottom to the input bearing installation position 2031 and the intermediate bearing installation position 2032. A third oil hole (not shown) is opened on the fifth pipeline 362, and the third oil hole leads to the input bearing installation position 2031, so as to cool the bearing installed at the input bearing installation position 2031.

[0077] like Figure 8-Figure 9 As shown, the oil in the fifth pipeline 362 flows into the sixth pipeline 363, and then flows from the sixth pipeline 363 into the middle bearing installation position 2032 to cool the bearing installed at the middle bearing installation position 2032. Fig. 9 The black straight arrows in the figure indicate the flow direction of the oil.

[0078] like Figure 8 As shown, the intermediate bearing installation position 2032 and the output bearing installation position 2033 are also connected through the seventh pipeline 364. Fig. 9 As shown, the oil flows from the intermediate bearing installation position 2032 to the output bearing installation position 2033 through the seventh pipeline 364 to cool the bearing installed at the output bearing installation position 2033.

[0079] like Fig.10 As shown, the outlet of the seventh pipeline 364 passes through the output bearing mounting position 2033 .

[0080] Therefore, through the provision of the third oil nozzle 361, the fifth pipeline 362, the sixth pipeline 363 and the seventh pipeline 364, each bearing on the reducer cover plate 203 can be cooled to achieve a precise cooling effect.

[0081] Furthermore, if Figure 15-16 As shown, the rotor core oil circuit includes a first rotor branch 42, a second rotor branch 43 and a third rotor branch 44. The first rotor branch 42 connects the weight reduction hole 4021 of the rotor core 402 and the inclined hole 4041 of the end plate 404. The second rotor branch 43 connects the inner magnetic steel hole 4022 of the rotor core 402 and the axial hole 4042 of the end plate. The third rotor branch 44 connects the outer magnetic steel hole 4023 of the rotor core 402 and the radial hole 4043 of the end plate.

[0082] Specifically, Fig.12 As shown, the motor 40 includes a motor shaft 401, a rotor core 402, an oil guide plate 403 and an end plate 404. The plurality of rotor cores 402 are sleeved on the outside of the motor shaft 401. The plurality of rotor cores 402 sandwich an oil guide plate 403. The oil guide plate 403 corresponds exactly to the plurality of divergent oil holes 411 on the motor shaft 401 (see Fig.15 ), two end plates 404 are covered at both ends of the multiple rotor cores 402 and are sleeved outside the motor shaft 401.

[0083] like Fig.15 As shown, Fig.15 The black straight arrow in the middle indicates the flow direction of the oil in the first rotor branch 42. Specifically, the oil flows from the multiple divergent oil holes 411 of the motor shaft 401 to the oil guide plate 403.

[0084] like Fig.14 As shown, the oil guide plate 403 is provided with a first oil guide hole 4031 , a second oil guide hole 4032 and a third oil guide hole 4033 , three oil guide holes form a group, and multiple groups are evenly distributed on the oil guide plate 403 along the circumferential direction.

[0085] Among them, Fig.13 As shown, the first oil guide hole 4031 corresponds to the weight-reducing hole 4021 on the rotor core 402 , and the weight-reducing hole 4021 corresponds to the inclined hole 4041 of the end plate 404 .

[0086] like Fig.15 As shown, the oil flows from the oil guide plate 403 into the weight-reducing holes 4021 on the rotor core 402, flows axially through a plurality of corresponding weight-reducing holes 4021 to cool the rotor core 402, and finally flows out from the inclined holes 4041 of the end plates 404 at both ends. After flowing out, the oil can splash onto the stator to cool the stator.

[0087] like Fig.14 As shown, the second oil guide hole 4032 on the oil guide plate 403 corresponds to Fig.13 The inner magnetic steel hole 4022 of the rotor core 402 corresponds to the axial hole 4042 on the end plate 404, and the oil in the second rotor branch 43 eventually flows out of the end plate 404 from the axial hole 4042 along the axial direction.

[0088] like Fig.14 As shown, the third oil guide hole 4033 on the oil guide plate 403 corresponds to Fig.13 The outer magnetic steel hole 4023 of the rotor core 402 corresponds to the radial hole 4043 on the end plate 404, and the oil in the third rotor branch 44 eventually flows out of the end plate 404 in the radial direction from the radial hole 4043.

[0089] In this embodiment, the oil can directly cool the inner and outer magnetic steels and the iron core, which can effectively reduce the temperature of the magnetic steels and the rotor, avoid overheating and demagnetization of the magnetic steels, and protect the safety of the magnetic steels. At the same time, magnetic steels with low temperature resistance grades can be selected to reduce costs.

[0090] In some embodiments of the present invention, Figure 1As shown, the electric drive system includes an electronic control housing 30, a motor housing 20 and a reducer housing 10, and also includes the oil cooling system in any of the above embodiments. The motor housing 20 includes an end cover 201, a main housing 202 and a reducer cover plate 203. The main housing 202 and the reducer cover plate 203 are integrally formed, and the reducer cover plate 203 is covered on the reducer housing 10.

[0091] In this embodiment, the motor housing 20 and the reducer housing 10 share a reducer cover 203 , which increases the integration of the electric drive system and helps to reduce space occupation.

[0092] Furthermore, if Figure 1 As shown, there are two motor housings 20, which are symmetrically arranged on both sides of the reducer housing 10. Figure 6-Figure 7 As shown, the reducer housing 10 includes a first half shell 104 and a second half shell 105 , and the reducer has two sets of oil cooling circuits, which are symmetrically arranged in the first half shell 104 and the second half shell 105 .

[0093] Specifically, the electric drive system in this embodiment has two motors and two reducers, and one motor 40 is arranged in each of the two motor housings 20. There is only one reducer housing 10, and both reducers are installed in the one reducer housing 10.

[0094] like Figure 6-Figure 7 As shown, the reducer housing 10 includes a left-right symmetrical first half shell 104 and a second half shell 105, each of which is equipped with a reducer. Similarly, each of the two half shells is provided with a reducer oil cooling circuit, and the two ports of the first pipeline 331 are respectively connected to the third oil nozzles 361 on the two reducer cover plate branches 36.

[0095] Furthermore, if Fig.11 As shown, a motor 40 is installed in each of the two motor housings 20, and there are two motor oil cooling circuits, which are respectively arranged in the two motors 40. The oil flows from the two first oil nozzles 333 toward the central through hole 37 in the left and right directions, and then flows into the motor oil cooling circuits in the two motors 40.

[0096] In the present invention, the reducer oil cooling circuit is connected to the oil pump and the oil cooler, and the reducer oil cooling circuit realizes active cooling of the bearings and gears installed in the reducer housing, so that the cooling effect is better; at the same time, the reducer oil cooling circuit is connected with the motor oil cooling circuit, which improves the cooling efficiency; in addition, the reducer cooling circuit and the motor oil cooling circuit are both arranged inside the electric drive system, and there is no need to add external pipelines, so that the overall structure of the electric drive system is more compact and occupies less space.

[0097] The above description is only the principle and preferred embodiments of the present invention. It should be noted that, for those skilled in the art, several other modifications can be made based on the principle of the present invention, which should also be considered as the protection scope of the present invention.

Claims

1. An oil cooling system, comprising an oil pump, an oil cooler, a reducer oil cooling circuit and a motor oil cooling circuit, wherein the reducer oil cooling circuit is arranged in a reducer housing, the motor oil cooling circuit is arranged in a motor, the reducer housing comprises an input shaft mounting position, an intermediate shaft mounting position and an output shaft mounting position, and is characterized in that: The oil pump and the oil cooler are installed on the reducer housing, the oil pump transports the oil at the bottom of the reducer housing to the oil cooler, the oil cooler is used to connect to the water cooling system of the vehicle and cool the oil, and the oil cooler transports the cooled oil to the reducer oil cooling circuit; The reducer oil cooling circuit includes an oil cooling inlet, an oil cooling outlet, an input shaft branch, and an output shaft branch. The oil cooling inlet and the oil cooling outlet are opened on the side of the reducer housing. The oil pump and the oil cooler are both installed on the side of the reducer housing. The oil cooling inlet is connected to the inlet of the oil cooler, and the oil cooling outlet is connected to the outlet of the oil cooler. The oil cooling inlet is communicated with the oil pump. The oil enters the oil cooling inlet from the oil pump and then flows into the oil cooler from the oil cooling inlet. The oil cooled by the oil cooler flows into the oil cooling outlet. The oil cooling outlet is communicated with the input shaft branch. The input shaft branch is used to bring the oil to the input shaft installation position. The oil flows from the input shaft branch into the output shaft branch. The output shaft branch is used to send the oil to the intermediate shaft installation position and the output shaft installation position. The motor oil cooling circuit includes a motor shaft main line and a rotor core oil line, the input shaft branch is connected to the motor shaft main line, and the motor shaft main line is connected to a plurality of rotor core oil lines; an input shaft is connected between the motor and the reducer housing; The input shaft branch includes a first pipeline, a second pipeline and a first oil nozzle, the first pipeline is arranged inside the side wall shell of the reducer housing, the oil cooling outlet is communicated with the first pipeline, the first oil nozzle is arranged at the center of the input shaft mounting position of the reducer housing, the second pipeline is arranged inside the housing of the reducer housing, one end of the second pipeline is communicated with the first pipeline, and the other end is connected to the first oil nozzle, the first oil nozzle is communicated with the central through hole of the input shaft, and the central through hole is connected to the motor shaft main pipeline; the output shaft branch is arranged inside the housing of the reducer housing, the output shaft branch includes a third pipeline and a fourth pipeline, the third pipeline extends obliquely upward from the first pipeline to the upper part of the intermediate shaft mounting position of the reducer housing, one end of the fourth pipeline is communicated with the third pipeline, and the other end extends to the upper part of the output shaft mounting position of the reducer housing, and the fourth pipeline is provided with a first oil hole and a second oil hole, the first oil hole leads to the intermediate shaft mounting position, and the second oil hole leads to the output shaft mounting position.

2. The oil cooling system according to claim 1, characterized in that: The reducer oil cooling circuit also includes a second oil nozzle, which is connected to the fourth pipeline and extends to the input shaft installation position of the reducer housing.

3. The oil cooling system according to claim 1, characterized in that: The reducer oil cooling circuit also includes a reducer cover branch, the reducer cover branch is arranged inside the reducer cover, and the first pipeline is connected to the reducer cover branch.

4. The oil cooling system according to claim 3, characterized in that: The reducer cover plate includes an input bearing mounting position, an intermediate bearing mounting position and an output bearing mounting position; The reducer cover branch includes a third oil nozzle, a fifth pipeline, a sixth pipeline and a seventh pipeline. The third oil nozzle is connected to the end of the first pipeline. The fifth pipeline is arranged above the input bearing mounting position and the intermediate bearing mounting position. One end of the fifth pipeline is connected to the third oil nozzle. A third oil hole is opened on the fifth pipeline, and the third oil hole leads to the input bearing mounting position. One end of the sixth pipeline is connected to the fifth pipeline, and the other end is connected to the intermediate bearing mounting position. The seventh pipeline connects the intermediate bearing mounting position with the output bearing mounting position.

5. The oil cooling system according to claim 1, characterized in that: The rotor core oil circuit includes a first rotor branch, a second rotor branch and a third rotor branch. The first rotor branch connects the weight-reducing hole of the rotor core and the inclined hole of the end plate. The second rotor branch connects the inner magnetic steel hole of the rotor core and the axial hole of the end plate. The third rotor branch connects the outer magnetic steel hole of the rotor core and the radial hole of the end plate.

6. An electric drive system, comprising an electric control housing, a motor housing and a reducer housing, characterized in that: It also includes the oil cooling system according to any one of claims 1 to 5, wherein the motor housing includes an end cover, a main housing and a reducer cover plate, the main housing and the reducer cover plate are integrally formed, and the reducer cover plate is covered on the reducer housing.

7. The electric drive system according to claim 6, characterized in that: The motor housing has two parts, which are symmetrically arranged on both sides of the reducer housing. The reducer housing includes a first half shell and a second half shell. The reducer oil cooling circuit has two parts, which are symmetrically arranged in the first half shell and the second half shell.

8. The electric drive system according to claim 7, characterized in that: One motor is installed in each of the two motor housings, and there are two sets of motor oil cooling circuits, which are respectively arranged in the two motors.

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