Electric motor having oil hole on each mounting surface, power assembly and electric vehicle

Abstract

The present application provides an electric motor having an oil hole on each mounting surface, a power assembly and an electric vehicle. The electric motor comprises a motor housing and an end cover, the motor housing comprises a motor accommodating cavity and a housing mounting surface, the housing mounting surface comprises a housing oil outlet hole, and the housing oil outlet hole is adapted to be in communication with an internal oil channel of the motor housing. The end cover comprises an end cover mounting surface, the end cover mounting surface is used for fixing the housing mounting surface, the end cover mounting surface comprises an end cover oil inlet hole, and the end cover oil inlet hole is adapted to be in communication with the housing oil outlet hole and an internal oil channel of the end cover. In the radial direction of the electric motor, the housing mounting surface surrounds the periphery of the motor accommodating cavity. In the axial direction of the electric motor, the opening of the housing oil outlet hole faces the end cover, the opening of the end cover oil inlet hole faces the motor housing, and the projection of the housing oil outlet hole at least partially overlaps the projection of the end cover oil inlet hole. According to the present application, some cooling oil in the motor housing is distributed to the end cover by means of the housing oil outlet hole and the end cover oil inlet hole, thereby avoiding insufficient local cooling and lubrication, reducing the impact of the rotating speed of an oil pump on the cooling and lubricating effect, and improving the system reliability.

Description

Motor, powertrain and electric vehicle with oil hole on mounting surface

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on December 14, 2023, with application number 202311724597.X and application name “Motor, powertrain and electric vehicle with oil holes on mounting surface”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the technical field of electric vehicles, and in particular to a motor, a powertrain, and an electric vehicle having an oil hole on a mounting surface. Background Art

[0003] The motor, which converts electrical energy into mechanical energy in the powertrain, typically requires cooling oil to cool and lubricate its key components. However, when the oil pump is operating at low speed, the motor may experience insufficient local cooling and lubrication, which can adversely affect the reliability of the powertrain. Summary of the Invention

[0004] The present application provides a motor, a powertrain, and an electric vehicle with an oil hole on a mounting surface.

[0005] In a first aspect, the present application provides a motor having an oil hole on a mounting surface. The motor comprises a motor housing and an end cap. The motor housing is used to secure the motor's stator. The motor housing comprises a housing mounting surface. The end cap comprises an end cap mounting surface, which is fixedly connected to the housing mounting surface along the motor's axial direction. The housing mounting surface comprises a housing oil outlet hole, which is used to communicate with an internal oil passage of the motor housing. The end cap mounting surface comprises an end cap oil inlet hole, which is used to communicate with the housing oil outlet hole and the internal oil passage of the end cap.

[0006] In the embodiment of the present application, cooling oil enters the internal oil passage of the motor housing through the housing oil passage, the housing oil outlet, and the end cover oil inlet to cool and lubricate other internal components of the motor. The embodiment of the present application diverts part of the cooling oil in the motor housing's internal oil passage directly to the internal oil passage of the end cover through the housing oil outlet and end cover oil inlet, thereby expanding the coverage of the cooling oil in the motor and enabling some components near the end cover to directly receive the cooling oil delivered from the housing's internal oil passage for cooling and lubrication. The cooling and lubrication effect is less affected by the oil pump speed, and the oil circuit remains reliable at low oil pump speeds.

[0007] In one embodiment, the housing oil outlet opening faces the end cap, and the end cap oil inlet opening faces the motor housing along the motor axis. This allows cooling oil flowing out of the housing oil outlet to flow directly into the end cap oil inlet along the motor axis, shortening the cooling oil flow path.

[0008] In one embodiment, along the motor axis, the projections of the housing oil outlet hole and the end cover oil inlet hole overlap, so that the cooling oil flow resistance between the housing oil outlet hole and the end cover oil inlet hole is smaller and the flow is smoother.

[0009] In one embodiment, the motor housing includes an internal oil passage for conveying cooling oil to the housing oil outlet. The diameter of the housing oil outlet is smaller than the inner diameter of the internal oil passage. Along the motor's axial direction, the internal oil passage, the housing oil outlet, and the end cap are arranged in sequence.

[0010] In an embodiment of the present application, the diameter of the housing's oil outlet hole is smaller than the inner diameter of the housing's internal oil passage, which can ensure that only a small portion of the cooling oil flows into the end cover's internal oil passage, preventing all the cooling oil from flowing out of the housing's oil outlet hole and failing to cool other parts of the motor. In one embodiment, the housing's internal oil passage is also connected to the motor's accommodating cavity, and the diameter of the housing's oil outlet hole is relatively small, so that most of the cooling oil can cool the stator, rotor, and motor shaft in the motor's accommodating cavity. The housing's internal oil passage, the housing's oil outlet hole, and the end cover are arranged in sequence along the motor's axial direction, and the arrangement direction of the three is the direction of movement of the cooling oil between the motor housing and the end cover.

[0011] In one embodiment, the diameter of the oil outlet hole of the housing is smaller than the diameter of the oil inlet hole of the end cover, so that the cooling oil flowing out of the oil outlet hole of the housing can smoothly enter the oil inlet hole of the end cover, reducing oil resistance.

[0012] In one embodiment, the inner surface of the motor housing includes a stator oil inlet hole, which is used to connect the internal oil channel of the housing and the gap between the motor housing and the stator or the internal oil channel of the stator, and the inner diameter of the housing oil outlet hole is smaller than the inner diameter of the stator oil inlet hole.

[0013] In the embodiment of the present application, the internal oil passage of the housing communicates with the gap between the motor housing and the stator, or the internal oil passage of the stator, through the stator oil inlet. A portion of the cooling oil in the internal oil passage of the housing flows through the stator oil inlet into the motor housing cavity to cool the motor's stator. Another portion of the cooling oil flows through the housing oil outlet and the end cover oil inlet into the internal oil passage of the end cover to cool and lubricate components within the motor near the end cover. The inner diameter of the housing oil outlet is smaller than that of the stator oil inlet, so that the cooling oil is rationally distributed between the motor housing cavity and the end cover, ensuring adequate cooling of the stator and rotor.

[0014] In one embodiment, the motor housing further includes a throttle hole, which is used to connect the housing's internal oil passage and the housing's oil outlet. The throttle hole is located axially between the housing's internal oil passage and the housing's oil outlet. The inner diameter of the throttle hole is smaller than the inner diameter of any of the stator's oil inlet hole, the housing's internal oil passage, and the housing's oil outlet.

[0015] In an embodiment of the present application, along the axial direction of the motor, the internal oil passage of the housing, the throttle hole and the oil outlet hole of the housing are arranged in sequence. When the cooling oil flows from the internal oil passage of the housing to the oil outlet hole of the housing, it will also pass through the throttle hole. The hole with a relatively small inner diameter among the throttle hole and the oil outlet hole of the housing is used to determine the flow rate of the cooling oil flowing to the end cover. In an embodiment of the present application, the inner diameter of the throttle hole is smaller than the inner diameter of any one of the stator oil inlet hole, the internal oil passage of the housing and the oil outlet hole of the housing, so that the throttle hole can play a role in controlling the flow rate. The throttle hole is far away from the oil inlet hole of the end cover relative to the oil outlet hole of the housing. The aperture of the throttle hole is small, and the flow resistance of the cooling oil at the throttle hole is large. The oil passage between the throttle hole and the oil outlet hole of the housing can play a buffering role, so that the flow resistance of the cooling oil when flowing from the oil outlet hole of the housing to the oil inlet hole of the end cover is reduced.

[0016] In one embodiment, the end cover also includes a motor bearing groove, which is recessed along the axial direction of the motor away from the motor housing. The motor bearing groove is used to accommodate and fix the outer ring of the motor bearing, and the inner ring of the motor bearing is used to be fixed to the motor shaft of the motor. The oil inlet hole of the end cover is used to communicate with the motor bearing groove through the internal oil channel of the end cover, and the motor bearing groove and the oil inlet hole of the end cover are arranged at intervals along the radial direction of the motor.

[0017] In an embodiment of the present application, the motor bearing is used to bear the load from the motor shaft, reduce friction, and ensure that the motor runs smoothly under high-speed conditions. Among them, the inner ring of the motor bearing is fixedly connected to the motor shaft, the outer ring of the motor bearing is fixedly connected to the motor bearing groove, and the inner ring and outer ring of the motor bearing are movably connected, so that the motor shaft can rotate relative to the end cover. If the motor bearing is not lubricated enough, the motor bearing may be burned or damaged. In an embodiment of the present application, the cooling oil flows through the oil outlet hole of the housing and the oil inlet hole of the end cover, and then enters the motor bearing groove through the internal oil channel of the end cover. Even if the oil pump is in a low-speed condition, the cooling oil can stably lubricate the motor bearing, avoiding the situation of insufficient local cooling and lubrication of the motor.

[0018] In one embodiment, the end cover further includes a avoidance groove, which is recessed from the end cover mounting surface in the direction away from the motor housing along the motor axis, and the motor bearing slot, the avoidance groove and the end cover mounting surface are arranged adjacent to each other in sequence along the motor radial direction, and the outer circumferential groove wall of the avoidance groove includes an end cover oil outlet hole, and the end cover oil outlet hole is used to connect the end cover oil inlet hole and the motor bearing slot through the internal oil channel of the end cover. Wherein, the opening direction of the end cover oil outlet hole intersects with both the motor radial direction and the motor axial direction. The arrangement direction of the end cover oil outlet hole and the end cover oil inlet hole intersects with both the motor radial direction and the motor axial direction. Along the motor axial direction, the housing oil outlet hole, the end cover oil inlet hole and the end cover oil outlet hole are arranged in sequence at intervals. Along the motor radial direction, the motor bearing slot, the end cover oil outlet hole and the end cover oil inlet hole are arranged in sequence at intervals.

[0019] In an embodiment of the present application, the recessed direction of the avoidance groove is parallel to the recessed direction of the motor bearing groove. The avoidance groove is located between the motor bearing groove and the end cover mounting surface along the radial direction of the motor. The avoidance groove provides space for fixing and mounting at least one of the motor winding, oil injection ring, or rotary transformer. The end cover oil outlet hole is used to guide cooling oil from the end cover oil inlet hole. The end cover oil outlet hole is located on the circumferential groove wall of the avoidance groove so that the cooling oil flows out from the circumferential groove wall of the avoidance groove. In an embodiment of the present application, the cooling oil flows through the end cover oil inlet hole and the end cover oil outlet hole and then enters the motor bearing groove, thereby cooling and lubricating the motor bearing.

[0020] In the embodiment of the present application, the opening direction of the end cover oil outlet hole intersects both the radial direction and the axial direction of the motor. This facilitates forming the end cover oil outlet hole on the circumferential groove wall of the avoidance groove, thereby avoiding obstruction by the motor bearing groove or the inner axial groove wall of the avoidance groove during the formation of the end cover oil outlet hole.

[0021] In the embodiment of the present application, the motor bearing slot is spaced apart from the end cap mounting surface in both the axial and radial directions. The end cap oil outlet and end cap oil inlet holes are arranged in directions that intersect both the motor radial and axial directions. Along the motor axial direction, the housing oil outlet hole, the end cap oil inlet hole, and the end cap oil outlet hole are sequentially spaced apart. Along the motor radial direction, the motor bearing slot, the end cap oil outlet hole, and the end cap oil inlet hole are sequentially spaced apart. This allows cooling oil delivered by the end cap oil inlet hole to be delivered radially and circumferentially, thereby improving the cooling and lubrication effect on the motor bearings.

[0022] In one embodiment, the end cover also includes an internal oil channel of the end cover, which is used to connect the oil inlet hole and the oil outlet hole of the end cover. The internal oil channel of the end cover passes through the circumferential groove wall of the avoidance groove. The arrangement direction of the oil inlet hole and the oil outlet hole of the end cover is the extension direction of the internal oil channel of the end cover, which can shorten the flow path of the cooling oil between the oil inlet hole and the oil outlet hole of the end cover. Since the oil outlet hole of the end cover is located on the circumferential groove wall of the avoidance groove, it is also beneficial to save structural parts such as oil plugs and reduce costs.

[0023] In one embodiment, the end cap internal oil passage and the end cap oil inlet are integrally die-cast. This embodiment eliminates the need for separate machining of the two, saving steps and improving the structural strength of the end cap internal oil passage and the end cap oil inlet. In one embodiment, the end cap internal oil passage can be formed by machining the end cap oil outlet.

[0024] In one embodiment, the bottom of the avoidance groove further includes an oil guide rib, which is used to connect the motor bearing groove and the end cover oil outlet hole. The oil guide rib protrudes from the bottom of the avoidance groove toward the end cover mounting surface along the motor axis. The oil guide rib is arranged between the end cover oil outlet hole and the motor bearing groove.

[0025] In the embodiment of the present application, an oil guide rib protrudes from the bottom of the avoidance groove toward the end cap mounting surface along the motor axis, allowing the rib to receive cooling oil flowing from the end cap oil outlet. The end cap oil outlet, oil guide rib, and motor bearing groove are arranged in sequence, allowing the rib to guide the cooling oil toward the motor bearing groove. Because the oil guide rib protrudes from the bottom of the avoidance groove, there is no gap between the rib and the bottom of the avoidance groove, which helps prevent cooling oil leakage.

[0026] In one embodiment, the motor bearing slot includes an oil inlet hole for connecting the motor bearing slot with an oil guide rib. The oil inlet hole extends radially through the inner and outer sides of the circumferential slot wall of the motor bearing slot. The oil inlet hole and the end cap oil outlet hole are arranged on the same side of the oil guide rib.

[0027] In the embodiment of the present application, the motor bearing slot oil inlet hole extends radially through the circumferential slot wall of the motor bearing slot. The motor bearing slot oil inlet hole is arranged adjacent to the oil guide rib. Cooling oil passes through the motor bearing slot oil inlet hole to lubricate the motor bearing, preventing severe wear of the motor bearing. Furthermore, the end cap oil outlet hole and the motor bearing slot oil inlet hole are located on the same side of the oil guide rib. The cooling oil has a shorter flow path from the end cap oil outlet hole to the motor bearing slot oil inlet hole, which helps reduce flow resistance of the cooling oil.

[0028] In one embodiment, the oil inlet hole of the end cap is higher than the oil inlet hole of the motor bearing slot in the direction of gravity. In this embodiment of the present application, the flow of cooling oil on the oil guide rib is affected by gravity. When the motor is used in a vehicle, the oil inlet hole of the end cap is higher than the oil inlet hole of the motor bearing slot in the direction of gravity. This will make the flow of cooling oil on the oil guide rib more efficient, help reduce the loss of cooling oil along the movement path, and thus improve the lubrication effect of the cooling oil on the motor bearing.

[0029] In one embodiment, the arrangement direction of the oil inlet hole of the motor bearing groove, the oil guide rib and the oil outlet hole of the end cover intersects with the radial direction of the motor.

[0030] In the embodiment of the present application, due to the influence of the opening direction of the oil outlet hole of the end cover, the cooling oil has a spray angle when flowing out of the oil outlet hole of the end cover. If the arrangement direction of the oil outlet hole of the end cover, the oil guide rib and the oil inlet hole of the motor bearing slot is parallel to the radial direction of the motor, it will make it difficult for the cooling oil to be accurately sprayed on the oil guide rib, resulting in loss of cooling oil. Specifically, when the motor is used in a vehicle scenario, if the arrangement direction of the oil outlet hole of the end cover, the oil guide rib and the oil inlet hole of the motor bearing slot is parallel to the radial direction, when the oil outlet hole of the end cover is located above the oil inlet hole of the motor bearing slot along the direction of gravity, the oil guide rib is vertically downward along the direction of gravity, which may cause the cooling oil to be unable to flow completely along the oil guide rib, thereby reducing the amount of cooling oil flowing into the oil inlet hole of the motor bearing slot. In the embodiment of the present application, the surface of the oil guide rib facing the oil inlet hole of the motor bearing groove and the oil outlet hole of the end cover is an oil guide surface for receiving the cooling oil and guiding the flow of the cooling oil. The difference between the spray angle of the cooling oil and the inclination angle of the oil guide rib is small, so that the cooling oil will not splash everywhere after being sprayed out from the oil outlet hole of the end cover, ensuring that the cooling oil can stably lubricate the motor bearings.

[0031] In one embodiment, the motor further includes a hollow pin. The hollow pin is hollow in structure. The housing oil outlet hole is configured to accommodate a portion of the hollow pin, while the remaining portion of the hollow pin protrudes axially from the housing mounting surface. The end cap oil inlet hole is configured to accommodate the remaining portion of the hollow pin. The hollow pin is configured to connect the housing oil outlet hole and the end cap oil inlet hole. In the radial direction of the motor, the outer diameter of the hollow pin is less than or equal to the inner diameter of the housing oil outlet hole and the end cap oil inlet hole, and the wall thickness of the hollow pin is less than the inner diameter of the hollow pin.

[0032] In the embodiments of the present application, the outer diameter of the hollow pin is less than or equal to the inner diameter of the housing oil outlet and end cap oil inlet, facilitating the hollow pin's axial insertion through the housing oil outlet and end cap oil inlet. Furthermore, the hollow pin's hollow structure ensures that the cooling oil flowing between the housing oil outlet and end cap oil inlet is not blocked by the hollow pin. The hollow pin's wall thickness is less than its inner diameter, preventing excessive flow resistance of the cooling oil through the hollow pin.

[0033] In an embodiment of the present application, part of the hollow pin is located in the oil outlet of the housing, and part of the hollow pin is located in the oil inlet of the end cover. The hollow pin can prevent debris from mixing into the cooling oil. For example, in one embodiment, a sealing glue can be applied between the housing mounting surface and the end cover mounting surface. The housing mounting surface and the end cover mounting surface are the sealing surfaces of the motor housing and the end cover. The sealing glue can enhance the stability and sealing performance of the fixed connection between the motor housing and the end cover. If the hollow pin is not passed through the housing oil outlet hole and the end cover oil inlet hole, the sealing glue may leak into the housing oil outlet hole and the end cover oil inlet hole, hindering the normal flow of the cooling oil. When a large amount of sealing glue accumulates in the housing oil outlet hole and the end cover oil inlet hole, it may directly cause blockage. The hollow pin in the embodiment of the present application can prevent debris such as sealing glue from entering the housing oil outlet hole and the end cover oil inlet hole. At the same time, the hollow structure can ensure that the hollow pin itself does not have a negative impact on the flow of the cooling oil.

[0034] In a second aspect, an embodiment of the present application provides a powertrain, comprising a heat exchanger and a motor as described above, wherein the heat exchanger is configured to deliver cooling oil to the internal oil passage of the motor. The embodiment of the present application diverts a portion of the cooling oil in the internal oil passage of the motor housing directly to the internal oil passage of the end cover through the housing oil outlet and the end cover oil inlet, thereby expanding the coverage of the cooling oil in the motor and enabling some components near the end cover to directly receive the cooling oil delivered from the internal oil passage of the housing for cooling and lubrication. The cooling and lubrication effect is less affected by the oil pump speed, and the oil circuit remains reliable at low oil pump speeds, thereby facilitating cooling and lowering the temperature of the powertrain during operation and improving the operating efficiency of the powertrain.

[0035] Thirdly, embodiments of the present application provide an electric vehicle comprising a frame, wheels, and a powertrain as described above, the powertrain also including a reducer. The frame secures the powertrain, the reducer's input shaft drives the motor shaft, and the reducer's output shaft drives the wheels. In embodiments of the present application, oil is directly delivered to the motor's end cap via the motor housing's mounting surface, improving heat dissipation from the powertrain and overall vehicle performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments of the present application will be described below.

[0037] FIG1 is a schematic structural diagram of an electric vehicle provided in one embodiment of the present application;

[0038] FIG2 is a schematic structural diagram of a powertrain and wheels provided in one embodiment of the present application;

[0039] FIG3 is an exploded view of a motor housing and an end cover provided in one embodiment of the present application;

[0040] FIG4 is a schematic structural diagram of an end cap provided in one embodiment of the present application;

[0041] FIG5 is a cross-sectional view of a motor provided in one embodiment of the present application;

[0042] FIG6 is a partial enlarged view of the M portion of the motor shown in FIG5 ;

[0043] FIG7 is a schematic structural diagram of the end cover shown in FIG4 taken along AA;

[0044] FIG8 is a schematic structural diagram of a housing oil outlet hole and an end cover oil inlet hole provided in an embodiment of the present application having hollow pins. DETAILED DESCRIPTION

[0045] The technical solutions in the embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments.

[0046] In this article, directional terms such as "upper" and "lower" are defined relative to the orientation of the structure schematically placed in the accompanying drawings. It should be understood that these directional terms are relative concepts. They are used for relative description and clarification, and they can change accordingly according to changes in the orientation of the structure.

[0047] In addition, references to "embodiments" or "implementations" herein mean that a particular feature, structure, or characteristic described in conjunction with the embodiment or implementation may be included in at least one embodiment of the present application. The appearance of such phrases in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0048] For ease of understanding, the relevant technical terms involved in the embodiments of this application are explained and described below.

[0049] Vertical: The vertical defined in the embodiments of the present application is not limited to an absolute vertical intersection relationship (an angle of 90 degrees). It allows for non-absolute vertical intersection relationships caused by factors such as assembly tolerance, design tolerance, and the influence of structural flatness. It allows for errors in a small angle range. For example, the assembly error range of 80 to 100 degrees can be understood as a vertical relationship.

[0050] Parallel: The parallelism defined in the embodiments of the present application is not limited to absolute parallelism. This definition of parallelism can be understood as basic parallelism, which allows for situations where the absolute parallelism is not caused by factors such as assembly tolerance, design tolerance, and the influence of structural flatness.

[0051] At present, when the oil pump speed is low, there is a problem of less cooling oil in some parts of the motor, resulting in poor heat dissipation and lubrication effects. An embodiment of the present application provides a motor with an oil hole on a mounting surface, the motor includes a motor housing and an end cover, the motor housing is used to fix the stator of the motor, the motor housing includes a housing mounting surface, the end cover includes an end cover mounting surface, and the end cover mounting surface is used to be fixedly connected to the housing mounting surface along the axial direction of the motor. Among them, the housing mounting surface includes a housing oil outlet hole, and the housing oil outlet hole is used to connect the housing internal oil channel of the motor housing. The end cover mounting surface includes an end cover oil inlet hole, and the end cover oil inlet hole is used to connect the housing oil outlet hole and the internal oil channel of the end cover. The cooling oil enters the internal oil channel of the end cover through the housing internal oil channel of the motor housing, the housing oil outlet hole, and the end cover oil inlet hole to cool and lubricate other internal components of the motor. The embodiment of the present application uses the oil outlet hole of the housing and the oil inlet hole of the end cover to directly divert part of the cooling oil in the internal oil channel of the motor housing to the internal oil channel of the end cover, thereby expanding the coverage of the cooling oil in the motor, so that some components close to the end cover side can directly receive the cooling oil transported from the internal oil channel of the housing for cooling and lubrication. The cooling and lubrication effect is less affected by the oil pump speed, and the oil circuit is still reliable at low oil pump speed.

[0052] The motor provided in the embodiment of the present application can be applied to a powertrain, and the powertrain including the motor of the present application can be applied to an electric vehicle.

[0053] Please refer to Figure 1, which is a schematic structural diagram of an electric vehicle 1 provided in one embodiment of the present application. In one embodiment, the electric vehicle 1 includes a frame 20, a powertrain 10, and wheels 30. The powertrain 10 and wheels 30 are mounted on the frame 20, and the powertrain 10 is used to drive the wheels 30 to rotate. The electric vehicle 1 refers to a wheeled device driven or towed by a power device.

[0054] In one embodiment, the electric vehicle 1 further includes a battery pack 40, which is mounted on the vehicle frame 20 and is used to provide electrical energy to the powertrain 10. The battery pack 40 is also referred to as a power battery.

[0055] Please refer to Figure 2, which is a schematic diagram of the structure of a powertrain 10 and a wheel 30 provided in one embodiment of the present application. In one embodiment, the powertrain 10 includes a heat exchanger 200 and a motor 100. The heat exchanger 200 is used to cool the cooling oil in the powertrain 10, and the cooling oil cools the motor 100. In one embodiment, the powertrain 10 also includes an oil pump (not shown) that is used to pump the cooling oil to the heat exchanger 200, providing power for the movement of the cooling oil.

[0056] In one embodiment, the powertrain 10 further includes a motor controller 300 and a reducer 400. The motor controller 300 is connected to the battery pack 40 and the motor 100, respectively. The motor controller 300 is used to convert the direct current transmitted by the battery pack 40 into alternating current, and transmit the alternating current to the motor 100. The motor 100 is used to provide driving force for the wheel 30 through the reducer 400. Specifically, in one embodiment, the motor shaft of the motor 100 is connected to the input shaft of the reducer 400 in a transmission connection (not shown), and the output shaft of the reducer 400 is connected to the wheel 30 in a transmission connection to drive the wheel 30 to move. It should be noted that Figure 2 only schematically shows the internal components of the powertrain 10 (motor, motor controller, reducer and heat exchanger), and does not represent the specific shape, size and position relationship of the internal components. For the purpose of simplicity, the connections between some components are hidden.

[0057] During operation, the motor 100 converts electrical energy into mechanical energy. There is loss in the energy conversion process, and the lost energy is released in the form of heat, causing the internal temperature of the motor 100 to rise. In addition, the internal components of the motor 100 are in a rotating state for a long time and may wear out. Therefore, the cooling oil introduced into the motor 100 by the heat exchanger 200 can play a role in cooling and lubrication. At present, the movement of cooling oil in the motor 100 mainly relies on the oil channel and the oil spraying of internal components. When the oil pump is at a low speed, the oil delivery effect is not good, making it difficult for the motor 100 to receive cooling and lubrication of the cooling oil locally, which will cause the internal components of the motor 100 to heat up or wear severely, thereby affecting the working efficiency and safety performance of the power assembly 10.

[0058] The embodiment of the present application improves the motor 100, connects multiple internal oil channels of the motor 100, and utilizes the internal oil channels to expand the coverage of the cooling oil in the motor 100, so that the cooling and lubrication effect is less affected by the oil pump speed, thereby avoiding the problem of insufficient local cooling and lubrication of the motor 100.

[0059] The motor 100 provided in an embodiment of the present application will be described in detail below.

[0060] Please refer to Figures 3 to 5. Figure 3 is an exploded view of the motor housing 110 and the end cover 120 provided in an embodiment of the present application. Figure 4 is a structural schematic diagram of the end cover 120 provided in an embodiment of the present application. Figure 5 is a cross-sectional view of the motor 100 provided in an embodiment of the present application.

[0061] In one embodiment, the motor 100 includes a motor housing 110 and an end cover 120 (as shown in Figures 3 and 5). The motor housing 110 is used to fix the stator 130 of the motor 100. The motor housing 110 includes a housing mounting surface 112 (as shown in Figure 3). The end cover 120 includes an end cover mounting surface 121 (as shown in Figure 4). The end cover mounting surface 121 is used to be fixedly connected to the housing mounting surface 112 along the motor axial direction O. The housing mounting surface 112 includes a housing oil outlet hole 1121 (as shown in Figures 3 and 5). The housing oil outlet hole 1121 is used to connect to the internal oil passage of the motor housing 110. The end cover mounting surface 121 includes an end cover oil inlet hole 1211 (as shown in Figure 4). The end cover oil inlet hole 1211 is used to connect the housing oil outlet hole 1121 with the internal oil passage of the end cover 120.

[0062] In this embodiment of the present application, along the motor radial direction R, the housing mounting surface 112 surrounds the outer circumference of the motor housing cavity 111 (as shown in FIG3 ). Along the motor axial direction O, the housing oil outlet hole 1121 opens toward the end cover 120 (as shown in FIG3 ), while the end cover oil inlet hole 1211 opens toward the motor housing 110 (as shown in FIG3 through FIG5 ). The projections of the housing oil outlet hole 1121 and the end cover oil inlet hole 1211 at least partially overlap.

[0063] In the embodiment of the present application, the motor housing 110 includes a motor accommodating cavity 111 , which is used to accommodate the stator 130 and the rotor 140 of the motor 100 (as shown in FIG. 5 ).

[0064] In an embodiment of the present application, the motor 100 is used to convert electrical energy into mechanical energy. Specifically, in one embodiment, the motor 100 also includes a stator 130, a rotor 140, a motor shaft 150 and a winding 160 (as shown in Figure 5). After the motor controller 300 passes alternating current into the winding 160, the alternating magnetic flux generated by the winding 160 interacts with the permanent magnetic flux generated by the rotor 140, causing the rotor 140 to rotate relative to the stator 130. The rotor 140 is fixedly connected to the motor shaft 150, so that the motor shaft 150 rotates with the rotor 140. The stator 130 is rotationally connected to the motor shaft 150, so that the motor shaft 150 can rotate relative to the stator 130, converting electrical energy into mechanical energy. The output end of the motor shaft 150 is used to transmit mechanical energy.

[0065] In the embodiment of the present application, the internal oil passage 113 of the motor housing 110 is configured to communicate with the housing oil outlet hole 1121. The housing mounting surface 112 of the motor housing 110 includes the housing oil outlet hole 1121, and the housing mounting surface 112 is configured to be fixed to the end cover mounting surface 121 of the end cover 120. The end cover mounting surface 121 includes an end cover oil inlet hole 1211. Along the motor axial direction O, the housing oil outlet hole 1121 and the end cover oil inlet hole 1211 face each other, and the projections of the housing oil outlet hole 1121 and the end cover oil inlet hole 1211 at least partially overlap. The end cover oil inlet hole 1211 is configured to communicate with the internal oil passage of the end cover 120, so that the internal oil passage 113 of the motor housing 110 communicates with the internal oil passage of the end cover 120 via the housing oil outlet hole 1121 and the end cover oil inlet hole 1211. In one embodiment, the cooling oil in the internal oil passage 113 of the motor housing 110 is used to cool the stator 130 in the motor housing cavity 111. The housing oil outlet 1121 and the end cover oil inlet 1211 divert some of the cooling oil in the motor housing 110 into the end cover 120, thereby expanding the coverage of the cooling oil's movement path within the motor 100. The motor axial direction O refers to the axial direction of the motor shaft 150, and the motor radial direction R refers to the radial direction of the motor shaft 150.

[0066] The power for the cooling oil to flow in the internal oil passages is mainly derived from the oil pump. In one embodiment, the motor bearings of the motor 100 are located within the end cap 120, and the cooling oil can lubricate the motor bearings through the internal oil passages of the end cap 120. If the rotor oil-swinging method is used to replace the end cap oil inlet hole 1211 and the internal oil passages of the end cap 120, when the motor rotor speed is high, the cooling oil will be difficult to move to the components that need to be cooled and lubricated (such as the motor bearings) within the end cap 120 due to the negative pressure, resulting in insufficient local cooling and lubrication of the motor 100, which can easily lead to damage to the internal components. For example, if an oil spraying method using an oil spray ring is adopted, wherein the oil spray ring is used to be fixed at the end of the winding 160, and the space between the oil spray ring, the inner wall of the motor accommodating cavity and the end of the stator is used to accommodate cooling oil, the oil pump delivers the cooling oil to the space enclosed by the oil spray ring, and then sprays the oil through the oil spray hole of the oil spray ring to lubricate the bearing of the end cover 120. When the power of the oil pump is insufficient or the oil pressure is insufficient, the space between the oil spray ring, the inner wall of the motor accommodating cavity and the end of the stator cannot be filled with cooling oil, so that the cooling oil cannot be sprayed to the bearing of the end cover 120 through the oil spray hole of the oil spray ring, and cooling and lubrication of the bearing of the end cover 120 or other components cannot be achieved. The housing oil outlet hole 1121 and the end cover oil inlet hole 1211 in the embodiment of the present application are connected, so that the flow of cooling oil between the internal oil channel of the motor housing 110 and the internal oil channel of the end cover 120 is more stable, and the cooling oil can flow stably into the internal oil channel of the end cover 120, with less influence from the power of the oil pump, which is not only beneficial to improving the distribution of cooling oil in the motor 100, but also can effectively cool and lubricate the bearings and other components of the end cover 120.

[0067] The embodiment of the present application utilizes the housing oil outlet hole 1121 and the end cover oil inlet hole 1211 to connect the internal oil channel of the motor housing 110 with the internal oil channel of the end cover 120, so that the cooling oil can stably cool and lubricate more devices. The cooling and lubrication effect is less affected by the power of the oil pump, avoiding local cooling and lubrication deficiency of the motor 100, which is beneficial to improving the reliability of the powertrain 10.

[0068] It should be noted that in the embodiments of this application, the projections of the hole, groove, and oil passage refer to the projection of the area enclosed by the hole wall, groove wall, and inner wall of the oil passage, respectively. In the embodiments of this application, the projection along the motor axial direction O refers to the projection along the motor axial direction O on a projection plane perpendicular to the motor axial direction O. The projection plane along the motor axial direction O is perpendicular to the motor axial direction O.

[0069] Please refer to Figures 5 and 6 . Figure 6 is a partial enlarged view of portion M of the motor 100 shown in Figure 5 . In one embodiment, the motor housing 110 includes internal oil passages 113 (as shown in Figures 5 and 6 ). The internal oil passages 113 are used to transport cooling oil to the housing oil outlet 1121. Along the motor radial direction R, the internal oil passages 113 are arranged at intervals outside the motor accommodating cavity 111 (as shown in Figure 5 ). Along the motor axial direction O, the internal oil passages 113, the housing oil outlet 1121, and the end cap 120 are arranged in sequence (as shown in Figure 6 ).

[0070] In the embodiment of the present application, the housing mounting surface 112 surrounds the outer periphery of the motor accommodating cavity 111 along the motor radial direction R, and the housing oil outlet 1121 is located on the housing mounting surface 112, which is equivalent to the housing oil outlet 1121 also surrounding the outer periphery of the motor accommodating cavity 111. The internal oil passage of the motor housing 110 includes a housing internal oil passage 113. The housing internal oil passage 113 is spaced apart from the outer side of the motor accommodating cavity 111 along the motor radial direction R to prevent the cooling oil from directly entering the motor accommodating cavity 111. The housing internal oil passage 113 can be used to control the position and flow rate of the cooling oil flowing into the motor accommodating cavity 111. The outer side of the motor accommodating cavity 111 refers to the side of the motor accommodating cavity 111 away from the stator 130 along the motor radial direction R. The housing internal oil passage 113, the housing oil outlet 1121, and the end cover 120 are arranged in sequence along the motor axial direction O. The arrangement direction of the three is the direction of movement of the cooling oil between the motor housing 110 and the end cover 120.

[0071] Please continue to refer to Figure 6. In one embodiment, the diameter of the housing oil outlet hole 1121 is smaller than the inner diameter of the housing internal oil passage 113. In the embodiment of the present application, the diameter of the housing oil outlet hole 1121 is denoted as D1, and the inner diameter of the housing internal oil passage 113 is denoted as D2. Among them, the diameter D1 of the housing oil outlet hole 1121 determines the flow rate of the cooling oil flowing from the motor housing 110 to the end cover 120. D1 is smaller than D2, which can ensure that only a small amount of cooling oil flows into the internal oil passage of the end cover 120, and avoids all the cooling oil flowing out of the housing oil outlet hole 1121 and failing to cool other parts of the motor. In one embodiment, the housing internal oil passage 113 is also connected to the motor accommodating cavity 111. The diameter D1 of the housing oil outlet hole 1121 is relatively small, so that most of the cooling oil can cool the stator, rotor and motor shaft in the motor accommodating cavity 111.

[0072] In one embodiment, the diameter of the housing oil outlet hole 1121 is smaller than the diameter of the end cover oil inlet hole 1211. The diameter of the end cover oil inlet hole 1211 is denoted as D3, where D1 is smaller than D3. This allows the cooling oil flowing out of the housing oil outlet hole 1121 to smoothly enter the end cover oil inlet hole 1211, reducing oil resistance.

[0073] Please continue to refer to Figure 6. In one embodiment, the inner surface of the motor housing 110 includes a stator oil inlet hole 1111, which is used to connect the internal oil channel 113 of the housing and the gap between the motor housing 110 and the stator 130 or the internal oil channel of the stator 130. The inner diameter of the housing oil outlet hole 1121 is smaller than the inner diameter of the stator oil inlet hole 1111.

[0074] In the embodiment of the present application, along the radial direction R of the motor, the stator oil inlet hole 1111 passes through the inner surface of the internal oil channel 113 of the shell, and the internal oil channel 113 of the shell is connected to the gap between the motor shell 110 and the stator 130 or the stator internal oil channel of the stator 130 through the stator oil inlet hole 1111. A part of the cooling oil in the internal oil channel 113 of the shell flows into the motor accommodating cavity 111 through the stator oil inlet hole 1111 to cool the stator 130 of the motor 100, and another part of the cooling oil enters the internal oil channel of the end cover 120 through the shell oil outlet hole 1121 and the end cover oil inlet hole 1211 to cool and lubricate the components in the motor 100 close to the side of the end cover 120. Among them, the inner diameter of the stator oil inlet hole 1111 is recorded as D4, and the aperture of the shell oil outlet hole 1121 is D1. The inner diameter D4 of the stator oil inlet hole 1111 determines the flow rate of the cooling oil flowing to the motor accommodating cavity 111. D1 is smaller than D4, and the cooling oil is reasonably distributed between the motor accommodating cavity 111 and the end cover 120 to ensure that the stator 130 and the rotor 140 can be fully cooled.

[0075] In the embodiment of the present application, the motor accommodating cavity 111 , the stator oil inlet hole 1111 , and the housing internal oil passage 113 are sequentially arranged adjacent to each other along the motor radial direction R, so that the cooling oil in the housing internal oil passage 113 enters the motor accommodating cavity 111 through the stator oil inlet hole 1111 .

[0076] Please continue to refer to Figures 5 and 6. In one embodiment, the motor accommodating cavity 111 includes a connecting section 1112 and a fixed section 1113. The inner diameter of the connecting section 1112 is larger than the inner diameter of the fixed section 1113. The fixed section 1113 is used to fix the stator 130. The stator oil inlet hole 1111 is located on the inner surface of the connecting section 1112. The inner surface of the connecting section 1112 is used to form an oil channel with the stator 130. In an embodiment of the present application, a connecting section 1112 and a fixed section 1113 are provided on the stator 130 along the axial direction O of the motor, wherein the fixed section 1113 is interference fit with the stator 130, so that the stator 130 is fixed in the fixed section 1113, and the connecting section 1112 and the stator 130 are arranged at intervals. The stator oil inlet hole 1111 is located in the connecting section 1112, and the cooling oil can flow into the gap between the connecting section 1112 and the stator 130 through the stator oil inlet hole 1111, and then move along the axial direction O of the motor on the outer surface of the stator 130. In one embodiment, the end of the winding 160 is located at the end of the stator 130 (as shown in Figure 5), and the cooling oil can move to the end of the winding 160 on the outer surface of the stator 130, thereby cooling the end of the winding 160.

[0077] Continuing with FIG6 , in one embodiment, the motor housing 110 further includes a throttle hole 114, which is used to connect the housing internal oil passage 113 and the housing oil outlet hole 1121. Along the motor axial direction O, the throttle hole 114 is located between the housing internal oil passage 113 and the housing oil outlet hole 1121. The inner diameter of the throttle hole 114 is smaller than the inner diameter of any of the stator oil inlet hole 1111, the housing internal oil passage 113, and the housing oil outlet hole 1121.

[0078] In the embodiment of the present application, along the motor axial direction O, the housing internal oil passage 113, the throttle hole 114, and the housing oil outlet hole 1121 are arranged in sequence. The projections of the housing internal oil passage 113, the throttle hole 114, and the housing oil outlet hole 1121 all at least partially overlap. When the cooling oil flows from the housing internal oil passage 113 to the housing oil outlet hole 1121, it also passes through the throttle hole 114. The inner diameter of the throttle hole 114 is denoted as D5. It is understandable that the hole with the relatively smaller inner diameter between the throttle hole 114 and the housing oil outlet hole 1121 is used to determine the flow rate of the cooling oil flowing to the end cover 120. In the embodiment of the present application, D5 is smaller than any of D1, D2, and D4, so that the throttle hole 114 can play a role in controlling the flow rate. The throttle hole 114 is far away from the end cover oil inlet hole 1211 relative to the shell oil outlet hole 1121. The aperture of the throttle hole 114 is small, and the flow resistance of the cooling oil at the throttle hole 114 is large. The oil channel between the throttle hole 114 and the shell oil outlet hole 1121 can play a buffering role, so that the flow resistance of the cooling oil is reduced when it flows from the shell oil outlet hole 1121 to the end cover oil inlet hole 1211.

[0079] Please refer to Figures 4 and 7 in combination. Figure 7 is a structural schematic diagram of the end cover 120 shown in Figure 4 cut along AA. In one embodiment, the end cover 120 further includes a motor bearing groove 122 (as shown in Figures 4 and 7). The motor bearing groove 122 is recessed away from the motor housing 110 along the motor axial direction O (as shown in Figure 7). The motor bearing groove 122 is used to accommodate and fix the outer ring of the motor bearing (not shown in the figure), and the inner ring of the motor bearing is used to be fixed to the motor shaft of the motor (not shown in the figure). The end cover oil inlet hole 1211 is used to communicate with the motor bearing groove 122 through the internal oil channel of the end cover 120. The motor bearing groove 122 and the end cover oil inlet hole 1211 are arranged at intervals along the radial direction R of the motor (as shown in Figure 7).

[0080] In an embodiment of the present application, the motor bearing is used to bear the load from the motor shaft 150, reduce friction, and ensure that the motor 100 runs smoothly under high-speed conditions. Among them, the inner ring of the motor bearing is fixedly connected to the motor shaft 150, the outer ring of the motor bearing is fixedly connected to the motor bearing groove 122, and the inner ring and outer ring of the motor bearing are movably connected, so that the motor shaft 150 can rotate relative to the end cover 120. If the motor bearing is not lubricated enough, the motor bearing may be burned or damaged. In an embodiment of the present application, the cooling oil flows through the oil outlet hole 1121 of the housing and the oil inlet hole 1211 of the end cover, and then enters the motor bearing groove 122 through the internal oil channel of the end cover 120. Even if the oil pump is in a low-speed condition, the cooling oil can stably lubricate the motor bearing, avoiding the situation of insufficient local cooling and lubrication of the motor 100.

[0081] In the embodiment of the present application, the recessed direction of the motor bearing groove 122 is away from the motor housing 110 , and the opening direction of the motor bearing groove 122 is toward the motor housing 110 , so as to facilitate the cooling oil to enter the motor bearing groove 122 through the internal oil channel of the end cover 120 .

[0082] Please continue to refer to Figures 4 and 7. In one embodiment, the end cover 120 also includes a avoidance groove 123 (as shown in Figures 4 and 7). The avoidance groove 123 is recessed from the end cover mounting surface 121 along the motor axial direction O toward the direction away from the motor housing 110 (as shown in Figure 7). Along the motor radial direction R, the motor bearing groove 122, the avoidance groove 123 and the end cover mounting surface 121 are arranged adjacent to each other in sequence (as shown in Figure 7). The circumferential groove wall of the avoidance groove 123 includes an end cover oil outlet hole 1231 (as shown in Figure 7). The end cover oil outlet hole 1231 is used to connect the end cover oil inlet hole 1211 and the motor bearing groove 122 through the internal oil channel of the end cover 120.

[0083] In the embodiment of the present application, the recessed direction of the avoidance groove 123 is parallel to the recessed direction of the motor bearing groove 122. The avoidance groove 123 is located between the motor bearing groove 122 and the end cover mounting surface 121 along the motor radial direction R. The avoidance groove 123 provides space for fixing and installing at least one of the motor winding, oil injection ring, or rotary transformer. The end cover oil outlet 1231 is used to lead the cooling oil from the end cover oil inlet 1211. The end cover oil outlet 1231 is located on the circumferential groove wall of the avoidance groove 123 so that the cooling oil flows out from the circumferential groove wall of the avoidance groove 123. As shown in FIG4 , the boss 101 connected to the circumferential groove wall of the avoidance groove 123 can also be regarded as a part of the circumferential groove wall of the avoidance groove 123, that is, the end cover oil outlet 1231 can be located on the boss 101.

[0084] In one embodiment, the opening direction of the end cover oil outlet hole 1231 intersects both the motor radial direction R and the motor axial direction O. The arrangement direction of the end cover oil outlet hole 1231 and the end cover oil inlet hole 1211 intersects both the motor radial direction R and the motor axial direction O. Along the motor axial direction O, the housing oil outlet hole 1121, the end cover oil inlet hole 1211, and the end cover oil outlet hole 1231 are sequentially arranged at intervals. Along the motor radial direction R, the motor bearing slot 122, the end cover oil outlet hole 1231, and the end cover oil inlet hole 1211 are sequentially arranged at intervals.

[0085] In the embodiment of the present application, the cooling oil flows through the end cover oil inlet hole 1211 and the end cover oil outlet hole 1231 and then enters the motor bearing groove 122 to achieve cooling and lubrication of the motor bearing. The arrangement direction of the end cover oil inlet hole 1211 and the end cover oil outlet hole 1231 intersects with the motor axial direction O and the motor radial direction R. In one embodiment, the end cover 120 also includes an end cover internal oil channel 124 (as shown in Figure 7). The end cover internal oil channel 124 is used to connect the end cover oil inlet hole 1211 and the end cover oil outlet hole 1231. The end cover internal oil channel 124 passes through the circumferential groove wall of the avoidance groove 123. The arrangement direction of the end cover oil inlet hole 1211 and the end cover oil outlet hole 1231 is the extension direction of the end cover internal oil channel 124, which can shorten the flow path of the cooling oil between the end cover oil inlet hole 1211 and the end cover oil outlet hole 1231. Since the end cover oil outlet hole 1231 is located on the circumferential groove wall of the avoidance groove 123, it is also beneficial to save structural parts such as oil plugs and reduce costs.

[0086] In one embodiment, the end cap internal oil passage 124 and the end cap oil inlet 1211 are integrally die-cast. This embodiment eliminates the need for separate machining of the two, saving steps and improving the structural strength of the end cap internal oil passage 124 and the end cap oil inlet 1211. In one embodiment, the end cap internal oil passage 124 can be machined through the end cap oil outlet 1231.

[0087] Continuing with Figures 4 and 7 , in one embodiment, the bottom of the avoidance groove 123 further includes an oil guide rib 1232 (as shown in Figures 4 and 7 ). The oil guide rib 1232 is used to connect the motor bearing groove 122 and the end cover oil outlet hole 1231. Along the motor axial direction O, the oil guide rib 1232 protrudes from the bottom of the avoidance groove 123 toward the end cover mounting surface 121 (as shown in Figure 7 ). The oil guide rib 1232 is arranged between the end cover oil outlet hole 1231 and the motor bearing groove 122 (as shown in Figure 7 ).

[0088] In the embodiment of the present application, the oil guide rib 1232 protrudes from the bottom of the avoidance groove 123 toward the end cover mounting surface 121 along the motor axial direction O, allowing the oil guide rib 1232 to receive the cooling oil flowing from the end cover oil outlet 1231. The end cover oil outlet 1231, the oil guide rib 1232, and the motor bearing groove 122 are arranged in sequence, allowing the oil guide rib 1232 to guide the cooling oil toward the motor bearing groove 122. Because the oil guide rib 1232 protrudes from the bottom of the avoidance groove 123, there is no gap between the oil guide rib 1232 and the bottom of the avoidance groove 123, which helps prevent cooling oil leakage.

[0089] Continuing with FIG7 , in one embodiment, the motor bearing slot 122 includes a motor bearing slot oil inlet hole 1221 , which is used to connect the motor bearing slot 122 with the oil guide rib 1232 . The motor bearing slot oil inlet hole 1221 extends through both the inner and outer sides of the circumferential slot wall of the motor bearing slot 122 along the motor radial direction R. The motor bearing slot oil inlet hole 1221 and the end cover oil outlet hole 1231 are arranged on the same side of the oil guide rib 1232 .

[0090] In the embodiment of the present application, the motor bearing slot oil inlet hole 1221 extends through the circumferential slot wall of the motor bearing slot 122 along the motor radial direction R. The motor bearing slot oil inlet hole 1221 is arranged adjacent to the oil guide rib 1232. Cooling oil passes through the motor bearing slot oil inlet hole 1221 to lubricate the motor bearings, thereby preventing severe wear of the motor bearings. The end cap oil outlet hole 1231 and the motor bearing slot oil inlet hole 1221 are located on the same side of the oil guide rib 1232. The cooling oil has a shorter flow path from the end cap oil outlet hole 1231 to the motor bearing slot oil inlet hole 1221, which helps reduce flow resistance of the cooling oil.

[0091] In one embodiment, along the direction of gravity, the end cap oil inlet hole 1211 is higher than the motor bearing slot oil inlet hole 1221. In this embodiment of the present application, the flow of cooling oil on the oil guide rib 1232 is affected by gravity. When the motor 100 is used in a vehicle, the end cap oil inlet hole 1211 is higher than the motor bearing slot oil inlet hole 1221 in the direction of gravity. This will make the flow of cooling oil on the oil guide rib 1232 more efficient, help reduce cooling oil loss along the movement path, and thus improve the cooling oil's lubrication effect on the motor bearings.

[0092] Continuing to refer to Figures 4 and 7, in one embodiment, the arrangement direction of the motor bearing slot oil inlet hole 1221, the oil guide rib 1232, and the end cover oil outlet hole 1231 intersects with the motor radial direction R. In this embodiment of the present application, due to the influence of the opening direction of the end cover oil outlet hole 1231, the cooling oil has a spray angle when flowing out of the end cover oil outlet hole 1231. If the arrangement direction of the end cover oil outlet hole 1231, the oil guide rib 1232, and the motor bearing slot oil inlet hole 1221 is parallel to the motor radial direction R, it will be difficult for the cooling oil to be accurately sprayed on the oil guide rib 1232, resulting in cooling oil loss. Specifically, when the motor 100 is used in a vehicle scenario, if the arrangement direction of the end cover oil outlet hole 1231, the oil guide rib 1232, and the motor bearing slot oil inlet hole 1221 is parallel to the radial direction, when the end cover oil outlet hole 1231 is located above the motor bearing slot oil inlet hole 1221 in the direction of gravity, the oil guide rib 1232 is vertically downward in the direction of gravity, which may cause the cooling oil to be unable to flow completely along the oil guide rib 1232, thereby reducing the amount of cooling oil flowing into the motor bearing slot oil inlet hole 1221. In the embodiment of the present application, the surface of the oil guide rib 1232 facing the motor bearing slot oil inlet hole 1221 and the end cover oil outlet hole 1231 is an oil guide surface for receiving and guiding the flow of cooling oil. The difference between the spray angle of the cooling oil and the inclination angle of the oil guide rib 1232 is small, so that the cooling oil will not splash everywhere after being sprayed from the end cover oil outlet hole 1231, ensuring that the cooling oil stably lubricates the motor bearings.

[0093] Please refer to Figure 8, which is a structural schematic diagram of a hollow pin in the oil outlet hole of the shell and the oil inlet hole of the end cover provided in an embodiment of the present application. In one embodiment, the motor 100 also includes a hollow pin 170, and the hollow pin 170 has a hollow structure. The oil outlet hole 1121 of the shell is used to accommodate part of the hollow pin 170, and the other part of the hollow pin 170 protrudes from the shell mounting surface 112 along the axial direction O of the motor. The oil inlet hole 1211 of the end cover is used to accommodate the other part of the hollow pin 170. The hollow pin 170 is used to connect the oil outlet hole 1121 of the shell and the oil inlet hole 1211 of the end cover, wherein, along the radial direction R of the motor, the outer diameter of the hollow pin 170 is less than or equal to the inner diameter of the oil outlet hole 1121 of the shell and the oil inlet hole 1211 of the end cover, and the wall thickness of the hollow pin 170 is less than the inner diameter of the hollow pin.

[0094] In the embodiment of the present application, the outer diameter of hollow pin 170 is less than or equal to the inner diameter of housing oil outlet hole 1121 and end cover oil inlet hole 1211, facilitating the insertion of hollow pin 170 through housing oil outlet hole 1121 and end cover oil inlet hole 1211 along the motor axial direction O. Furthermore, hollow pin 170 is hollow in structure, and the flow of cooling oil between housing oil outlet hole 1121 and end cover oil inlet hole 1211 is not blocked by hollow pin 170. The wall thickness of hollow pin 170 is less than its inner diameter, thereby preventing excessive flow resistance of cooling oil through the hollow pin.

[0095] Part of the hollow pin 170 is located in the housing oil outlet hole 1121, and part of the hollow pin 170 is located in the end cover oil inlet hole 1211. The hollow pin 170 can prevent foreign matter from mixing into the cooling oil. For example, in one embodiment, a sealing glue can be applied between the housing mounting surface 112 and the end cover mounting surface 121. The housing mounting surface 112 and the end cover mounting surface 121 are the sealing surfaces of the motor housing 110 and the end cover 120. The sealing glue can enhance the stability and sealing performance of the fixed connection between the motor housing 110 and the end cover 120. If the hollow pin 170 is not passed through the housing oil outlet hole 1121 and the end cover oil inlet hole 1211, the sealing glue may leak into the housing oil outlet hole 1121 and the end cover oil inlet hole 1211, hindering the normal flow of cooling oil. When a large amount of sealing glue accumulates in the housing oil outlet hole 1121 and the end cover oil inlet hole 1211, it may directly cause blockage. The hollow pin 170 in the embodiment of the present application can prevent debris such as sealing glue from entering the oil outlet hole 1121 of the shell and the oil inlet hole 1211 of the end cover. At the same time, the hollow structure can ensure that the hollow pin 170 itself does not have a negative impact on the flow of cooling oil.

[0096] The above is a detailed introduction to the motor, powertrain and electric vehicle with oil holes on the mounting surface provided in the embodiments of the present application. Specific examples are used herein to illustrate the principles and embodiments of the present application. The description of the above embodiments is only used to help understand the method and core idea of ​​the present application. At the same time, for those skilled in the art, according to the ideas of the present application, there will be changes in the specific embodiments and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A motor with an oil hole on the mounting surface, characterized in that: The motor comprises a motor housing and an end cover, wherein the motor housing is used to fix the stator of the motor, the motor housing comprises a housing mounting surface, and the end cover comprises an end cover mounting surface, and the end cover mounting surface is used to be fixedly connected to the housing mounting surface along the axial direction of the motor, wherein: The housing mounting surface includes a housing oil outlet hole, and the housing oil outlet hole is used to communicate with the housing internal oil passage of the motor housing; The end cover mounting surface comprises an end cover oil inlet hole, and the end cover oil inlet hole is used to connect the housing oil outlet hole and the internal oil passage of the end cover.

2. The motor according to claim 1, characterized in that The motor housing includes an internal oil passage of the housing, and the internal oil passage of the housing is used to transport cooling oil to the oil outlet hole of the housing, and the diameter of the oil outlet hole of the housing is smaller than the inner diameter of the internal oil passage of the housing, wherein: Along the axial direction of the motor, the oil passage inside the housing, the oil outlet hole of the housing and the end cover are arranged in sequence.

3. The motor according to claim 1 or 2, characterized in that: The diameter of the oil outlet hole of the housing is smaller than the diameter of the oil inlet hole of the end cover.

4. The motor according to claim 2, characterized in that The inner surface of the motor housing includes a stator oil inlet hole, which is used to connect the internal oil channel of the housing and the gap between the motor housing and the stator or the internal oil channel of the stator. The inner diameter of the housing oil outlet hole is smaller than the inner diameter of the stator oil inlet hole.

5. The motor according to claim 4, characterized in that The motor housing further comprises a throttle hole, and the throttle hole is used to connect the oil passage inside the housing and the oil outlet hole of the housing, wherein: Along the axial direction of the motor, the throttle hole is located between the oil passage inside the housing and the oil outlet hole of the housing; The inner diameter of the throttle hole is smaller than the inner diameter of any one of the stator oil inlet hole, the housing internal oil passage, and the housing oil outlet hole.

6. The motor according to any one of claims 1 to 5, characterized in that: The end cover also includes a motor bearing groove, which is recessed along the axial direction of the motor away from the motor housing, and is used to accommodate and fix the outer ring of the motor bearing. The inner ring of the motor bearing is used to be fixed to the motor shaft of the motor. The end cover oil inlet hole is used to communicate with the motor bearing groove through the internal oil channel of the end cover, and the motor bearing groove and the end cover oil inlet hole are arranged at intervals along the radial direction of the motor.

7. The motor according to claim 6, characterized in that The end cover further includes a position-avoiding groove, which is recessed from the end cover mounting surface in the direction away from the motor housing along the motor axial direction, and the motor bearing groove, the position-avoiding groove and the end cover mounting surface are sequentially arranged adjacent to each other along the motor radial direction, and the circumferential groove wall of the position-avoiding groove includes an end cover oil outlet hole, and the end cover oil outlet hole is used to connect the end cover oil inlet hole and the motor bearing groove through the internal oil passage of the end cover, wherein: The opening direction of the oil outlet hole of the end cover intersects both the radial direction of the motor and the axial direction of the motor; The arrangement direction of the oil outlet hole of the end cover and the oil inlet hole of the end cover intersects with both the radial direction of the motor and the axial direction of the motor; Along the axial direction of the motor, the housing oil outlet hole, the end cover oil inlet hole and the end cover oil outlet hole are sequentially arranged at intervals; Along the radial direction of the motor, the motor bearing groove, the end cover oil outlet hole and the end cover oil inlet hole are arranged in sequence and spaced apart.

8. The motor according to claim 7, characterized in that The groove bottom of the avoidance groove also includes an oil guide rib, and the oil guide rib is used to connect the motor bearing groove and the oil outlet hole of the end cover, wherein: Along the axial direction of the motor, the oil guide rib protrudes from the bottom of the avoidance groove toward the end cover mounting surface; The oil guide rib is arranged between the oil outlet hole of the end cover and the motor bearing groove.

9. The motor according to claim 8, characterized in that The motor bearing slot includes a motor bearing slot oil inlet hole, and the motor bearing slot oil inlet hole is used to connect the motor bearing slot and the oil guide rib, wherein: Along the radial direction of the motor, the oil inlet hole of the motor bearing groove penetrates the inner and outer sides of the circumferential groove wall of the motor bearing groove; The oil inlet hole of the motor bearing groove and the oil outlet hole of the end cover are arranged on the same side of the oil guide rib.

10. The motor according to claim 9, characterized in that The arrangement direction of the oil inlet hole of the motor bearing groove, the oil guide rib and the oil outlet hole of the end cover intersects with the radial direction of the motor.

11. The motor according to any one of claims 1 to 10, characterized in that: The motor further comprises a hollow pin, which is hollow in structure, the oil outlet hole of the housing is used to accommodate part of the hollow pin, and the other part of the hollow pin protrudes from the mounting surface of the housing along the axial direction of the motor, the oil inlet hole of the end cover is used to accommodate the other part of the hollow pin, and the hollow pin is used to connect the oil outlet hole of the housing and the oil inlet hole of the end cover, wherein: Along the radial direction of the motor, the outer diameter of the hollow pin is smaller than or equal to the inner diameter of the oil outlet hole of the housing and the oil inlet hole of the end cover, and the wall thickness of the hollow pin is smaller than the inner diameter of the hollow pin.

12. The motor according to any one of claims 1 to 11, characterized in that: Along the axial direction of the motor, the opening of the oil outlet hole of the housing faces the end cover, and the opening of the oil inlet hole of the end cover faces the motor housing.

13. The motor according to any one of claims 1 to 12, characterized in that: Along the axial direction of the motor, the projections of the oil outlet hole of the housing and the oil inlet hole of the end cover overlap.

14. A powertrain, characterized in that: The powertrain comprises a heat exchanger and a motor as claimed in any one of claims 1 to 13, wherein the heat exchanger is used to transport cooling oil to an internal oil passage of the motor.

15. An electric vehicle, characterized in that: The electric vehicle comprises a frame, wheels and a powertrain as claimed in claim 14, wherein the powertrain further comprises a reducer, wherein: The frame is used to fix the power assembly; The input shaft of the reducer is used for transmission connection with the motor shaft of the motor, and the output shaft of the reducer is used for transmission connection with the wheel.

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