Oil-cooled motor with cooling structure

Abstract

The utility model discloses an oil-cooled motor with a cooling structure, which comprises a cooling assembly, the cooling assembly comprises cooling rings arranged on two axial end faces of a stator assembly, an annular flow cavity with an opening end is formed in each cooling ring, a cooling cavity for placing an end winding is formed on the outer side face of each cooling ring, and the end winding is arranged in the cooling cavity. The flowing cavity, the cooling cavity and the gap can form a channel allowing cooling oil to flow. According to the utility model, through the arrangement of the cooling ring, external cooling oil can enter the flowing cavity through the open end, so that the cooling oil in the flowing cavity enters the cooling cavity through the side wall oil outlet hole and the end surface oil outlet hole, and the cooling oil in the cooling cavity can take away heat on the inner and outer surfaces of the end winding; and the heat of the winding in the slot can be indirectly taken away through the space between the stator core and the rotor core, so that the heat dissipation capability of the motor can be improved under the condition that the slot fullness rate is ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of motor cooling, and particularly relates to an oil-cooled motor with a cooling structure. Background Art

[0002] The slot fill factor is an important parameter for measuring the proportion of the space occupied by conductors in the stator slots of a motor. It refers to the ratio of the actual filling area of the conductors in the stator or rotor slots of the motor to the total area of the slots, which directly affects the efficiency, thermal management, and electromagnetic performance of the motor. The slot shoulder height refers to the height of the part above the slot opening of the stator or rotor of the motor that is not occupied by the winding. Its function is to provide mechanical support for the winding during the operation of the motor and help improve the ventilation and heat dissipation effect of the motor. With the continuous improvement of the power performance and economy of new energy vehicles, the motor is developing in the direction of high power, lightweight, and high torque. The motor winding gradually changes from circular to flat, resulting in a gradual increase in the slot fill factor and the power of the motor. However, when the slot fill factor is too high, the slot shoulder height will decrease, which may lead to poor heat dissipation of the motor and thus affect the service life of the motor.

[0003] The inventors of the present application found that the existing cooling structure of the oil-cooled motor is to increase the structure of the motor additionally, such as opening holes in the stator core or adding a spray structure in the slot. This method will affect the stator magnetic circuit structure, reduce the slot fill factor, and increase the size of the slot shoulder height, thus reducing the maximum torque and power of the motor. Therefore, the existing oil-cooling structure cannot improve the heat dissipation effect of the motor while increasing the motor power. Summary of the Utility Model

[0004] In order to solve the problem that the existing oil-cooling structure cannot improve the heat dissipation effect of the motor while increasing the motor power, the utility model provides an oil-cooled motor with a cooling structure, and the specific technical solutions are as follows:

[0005] An oil-cooled motor with a cooling structure includes a cooling component. The cooling component includes: cooling rings arranged on the axial end faces at both ends of the stator component. An annular flow cavity with an open end is formed inside the cooling ring. A cooling cavity for placing the end winding is formed on the outer side surface of the cooling ring. The flow cavity, the cooling cavity, and the gap can form a channel allowing the cooling oil to flow.

[0006] Further, the open end of the flow cavity is communicated with the gap. A side wall oil outlet hole for penetrating the flow cavity and the cooling cavity is formed on the radial side surface of the cooling ring close to the cooling cavity. An end face oil outlet hole for penetrating the flow cavity and the cooling cavity is formed on the axial end face of the cooling ring close to the cooling cavity.

[0007] Preferably, the rotor component includes: a rotating shaft for driving the cooling component to rotate, and the axis of the rotating shaft coincides with the axis of the cooling component; and a rotor core arranged on the radial outer side surface of the rotating shaft.

[0008] Preferably, the stator assembly further includes: an oil groove formed on the radially outer side surface of the stator core, the length direction of the oil groove being the axial direction of the stator core, the oil groove communicating with the open end of the flow cavity; and an in-slot winding disposed inside the stator core.

[0009] Preferably, the housing assembly includes: a motor housing for placing the stator core, the motor housing forming an oil inlet passage along the axial direction, and an oil inlet hole formed in the motor housing along the radial direction for communicating the oil inlet passage and the gap. As can be seen from the above technical solutions, the present utility model has the following beneficial effects:

[0010] In the present utility model, by respectively arranging cooling rings on the axial end faces of the stator core, the external cooling oil can enter the flow cavity through the open end, and then the cooling oil in the flow cavity enters the cooling cavity through the side wall oil outlet holes and the end face oil outlet holes, so that the cooling oil in the cooling cavity can take away the heat on the inner and outer surfaces of the end windings, and it can flow between the stator core and the rotor core to indirectly take away the heat of the in-slot winding, thereby realizing that increasing the cooling components at the axial end faces of the stator core can improve the heat dissipation capacity of the motor, and further enabling the motor to improve the heat dissipation capacity while ensuring the slot fill factor. Description of the Drawings

[0011] Figure 1 is a schematic structural diagram of the stator assembly and the cooling assembly of the present utility model;

[0012] Figure 2 is a sectional view of the present utility model;

[0013] Figure 3 is a schematic structural diagram of the cooling assembly of the present utility model.

[0014] In the figure: 1. Rotor assembly; 2. Stator assembly; 3. Cooling assembly; 4. Housing assembly; 11. Rotating shaft; 12. Rotor core; 21. Stator core; 22. Oil groove; 23. End winding; 24. In-slot winding; 31. Cooling ring; 32. Flow cavity; 33. Cooling cavity; 34. Side wall oil outlet hole; 35. End face oil outlet hole; 41. Motor housing; 42. Oil inlet passage; 43. Oil inlet hole. Detailed Embodiments

[0015] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present utility model.

[0016] In the description of the embodiments of the present invention, it should be noted that the terms "inside", "outside", "upper", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the product of the present invention is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as a limitation on the present invention.

[0017] like Figures 1 to 3 As shown, it can be known from common knowledge that the oil-cooled motor includes a housing assembly 4, a rotor assembly 1, a stator assembly 2 and a cooling assembly 3. The stator assembly 2 includes a stator core 21, and end windings 23 are set on both axial end faces of the stator core 21. There is a gap between the radial outer side surface of the stator core 21 and the radial inner side surface of the housing assembly 4 for the flow of cooling oil.

[0018] Specifically, a cavity for placing the stator assembly 2 is formed inside the housing assembly 4. The stator assembly 2 is coaxial with the rotor assembly 1, and there is a gap between the radial surfaces of the stator assembly 2 and the rotor assembly 1 to allow cooling oil to flow. During the operation of the motor, the end winding 23 and the slot winding 24 axially wound on the stator core 21 will generate heat due to the passage of current. The cooling oil flowing through the gap can take away the generated heat, thereby reducing the operating temperature inside the motor and increasing its service life.

[0019] Furthermore, the cooling assembly 3 includes: cooling rings 31 arranged on both axial end faces of the stator assembly 2, the interior of the cooling ring 31 forms a ring-shaped flow cavity 32 with an open end, and the outer side surface of the cooling ring 31 forms a cooling cavity 33 for placing the end winding 23, and the flow cavity 32, the cooling cavity 33 and the gap can form a channel allowing the cooling oil to flow.

[0020] Specifically, cooling rings 31 are fixedly connected to both axial end faces of the stator core 21, which are used to cool the end windings 23 and the slot windings 24 on the stator core 21, wherein the cooling ring 31 is a sandwich structure with an open end, and the sandwich structure is annular, forming a flow cavity 32 for the flow of running cooling oil, so that the cooling oil in the gap can flow into the flow cavity 32 through the open end, and then the cooling oil can flow around the axial end face of the stator core 21 through the annular structure. Secondly, the cooling ring 31 forms a concave shape at the position of the end winding 23 for placing the end winding 23, so that the cooling cavity 33 can contact the inner and outer sides of the end winding 23.

[0021] Among them, the gap communicates with the flow cavity 32 through the open end, and the flow cavity 32 and the cooling cavity 33 communicate through the through hole, so that the cooling oil in the gap can enter the flow cavity 32 through the open end, and then the cooling oil flows in the flow cavity 32, and then takes away the heat of the inner slot winding 24 by taking away the heat of the outer side surface of the stator core 21 in the axial direction. Secondly, the cooling oil flowing into the cooling cavity 33 through the through hole can contact the inner and outer sides of the end winding 23, so that the cooling oil can contact the end winding 23 generating heat in all directions, and then improve the heat dissipation effect of the end winding 23. Among them, no structural modification is required for the stator core 21 and the rotor core 12, so that the heat dissipation effect can be improved while ensuring the slot filling rate of the embodiment.

[0022] Further, the open end of the flow cavity 32 communicates with the gap, and the radial side surface of the cooling ring 31 close to the cooling cavity 33 forms a side wall oil outlet hole 34 for penetrating the side walls of the flow cavity 32 and the cooling cavity 33, and the axial end surface of the cooling ring 31 close to the cooling cavity 33 forms an end surface oil outlet hole 35 for penetrating the side walls of the flow cavity 32 and the cooling cavity 33.

[0023] Specifically, the open end of the flow cavity 32 surrounds the stator core 21 in the circumferential direction, and a part of the projection of the gap in the axial direction always coincides with the projection of the open end of the flow cavity 32 in the axial direction, so that the gap in the circumferential direction of the stator core 21 can always communicate with the open end of the flow cavity 32, and then the cooling oil in the gap at each position can enter the flow cavity 32 through the open end; secondly, the flow cavity 32 stores cooling oil, and the cooling oil can contact the inner and outer radial surfaces of the end winding 23 through the side wall oil outlet hole 34, and then take away the heat of the inner and outer radial surfaces of the end winding 23. The cooling oil in the flow cavity 32 can also contact the axial end surface of the end winding 23 through the end surface oil outlet hole 35, and then take away the heat of the axial end surface of the end winding 23, so that the cooling cavity 33 can contact all the outer surfaces of the circumferential end winding 23, and then improve the heat dissipation effect of the end winding 23.

[0024] Further, the rotor assembly 1 includes: a rotating shaft 11 for driving the cooling assembly 3 to rotate, and the rotating shaft 11 coincides with the axis of the cooling assembly 3; and a rotor core 12 arranged on the outer side surface of the rotating shaft 11 in the radial direction.

[0025] Specifically, the rotating shaft 11 drives the cooling assembly 3 to rotate, thereby driving the cooling oil inside the cooling assembly 3 to rotate, which in turn accelerates the cooling oil to enter the cooling cavity 33 to cool the end winding 23, improving the cooling efficiency. Secondly, the rotating shaft 11 and the cooling assembly 3 are coaxial, so that the centrifugal forces of the cooling oil at the same distance from the rotating shaft 11 inside the cooling assembly 3 are the same, thereby making the cooling cavity 33 cool the end winding 23 evenly. Secondly, there is also a gap between the rotor core 12 and the stator core 21, so that the cooling oil in the cooling cavity 33 can flow through the radial outer surface of the rotor core 12 to take away the heat of the rotor core 12, improving the cooling range and cooling capacity of the cooling assembly 3, and thus improving the heat dissipation capacity of the motor.

[0026] Further, the stator assembly 2 further includes: an oil groove 22 formed on the radial outer side surface of the stator core 21, the length direction of the oil groove 22 is the axial direction of the stator core 21, and the oil groove 22 communicates with the open end of the flow cavity 32; and an in-slot winding 24 disposed inside the stator core 21.

[0027] Specifically, the oil grooves 22 are evenly distributed on the radial outer side surface of the stator core 21 and penetrate the stator core 21, so that the cooling oil can be evenly distributed between the radial outer side surface of the stator core 21 and the radial inner side surface of the housing assembly 4. Then, the cooling oil in the gap can evenly enter the flow cavity 32 along the oil grooves 22, which in turn increases the amount of cooling oil entering each position of the flow cavity 32, so that the cooling oil can evenly take away the end winding 23. Secondly, the length direction of the in-slot winding 24 is the same as the length direction of the oil grooves 22. The evenly distributed oil grooves 22 enable the evenly distributed cooling oil to flow through the radial outer side surface of the stator core 21, so that the cooling oil can evenly take away the heat conducted from the in-slot winding 24 to the radial outer side surface of the stator core 21, thereby improving the heat dissipation capacity and the uniform heat dissipation capacity of the in-slot winding 24.

[0028] Further, the housing assembly 4 includes: a motor housing 41 for placing the stator core 21, the motor housing 41 forms an oil inlet passage 42 along the axial direction, and the motor housing 41 forms an oil inlet hole 43 along the radial direction to communicate the oil inlet passage 42 and the gap.

[0029] Specifically, there is a gap between the radial inner side surface of the motor housing 41 and the radial outer side surface of the stator core 21. Secondly, the external cooling oil enters the inside of the motor housing 41 through the oil inlet passage 42, and then enters the gap through the oil inlet hole 43, so that the external cooling oil can flow through the radial inner and outer surfaces of the stator core 21 to take away the heat of the in-slot winding 24, and flow through the cooling cavity 33 to take away the heat of the end winding 23, realizing the circulation of the cooling oil in the motor.

[0030] Although embodiments of the present invention have been shown and described, those of ordinary skill in the art will appreciate that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

[0031] The technologies, shapes, and structures not detailedly described in the present invention are all well-known technologies.

Claims

1. An oil-cooled motor with a cooling structure, the oil-cooled motor comprising a housing assembly (4), a rotor assembly (1), a stator assembly (2) and a cooling assembly (3), the stator assembly (2) comprising a stator core (21), end windings (23) being provided on axial end faces of the stator core (21), and there being a gap for the flow of cooling oil between a radially outer side face of the stator core (21) and a radially inner side face of the housing assembly (4), characterized in that, The cooling component (3) includes: Cooling rings (31) arranged on the axial end faces at both ends of the stator component (2). An annular flow cavity (32) with an open end is formed inside the cooling ring (31). A cooling cavity (33) for placing the end winding (23) is formed on the outer side surface of the cooling ring (31). The flow cavity (32), the cooling cavity (33), and the gap can form a channel allowing the cooling oil to flow.

2. The oil-cooled motor according to claim 1, characterized in that: The open end of the flow cavity (32) is communicated with the gap. A side wall oil outlet hole (34) for penetrating the flow cavity (32) and the cooling cavity (33) is formed on the radial side surface of the cooling ring (31) close to the cooling cavity (33). An end face oil outlet hole (35) for penetrating the flow cavity (32) and the cooling cavity (33) is formed on the axial end face of the cooling ring (31) close to the cooling cavity (33).

3. The oil-cooled motor according to claim 1, wherein: The rotor component (1) includes: A rotating shaft (11) for driving the cooling component (3) to rotate, and the axis of the rotating shaft (11) coincides with the axis of the cooling component (3); and a rotor core (12) arranged on the radial outer side surface of the rotating shaft (11).

4. The oil-cooled motor according to claim 1, characterized in that: The stator component (2) further includes: An oil groove (22) formed on the radial outer side surface of the stator core (21). The length direction of the oil groove (22) is the axial direction of the stator core (21), and the oil groove (22) is communicated with the open end of the flow cavity (32); and A slot winding (24) arranged inside the stator core (21).

5. The oil-cooled motor according to claim 1, characterized in that: The housing component (4) includes: a motor housing (41) for placing the stator core (21). An oil inlet oil path (42) is formed axially on the motor housing (41), and an oil inlet hole (43) communicating the oil inlet oil path (42) and the gap is formed radially on the motor housing (41).

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