Motor heat dissipation structure
By modifying the shape of the motor heat dissipation chamber to be tapered and adding oil holes, the problem of insufficient injection pressure in the existing motor heat dissipation structure is solved, and a more efficient cooling effect is achieved, avoiding the motor overheating.
Patent Information
- Application Number
- CN202421177666.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-27
- Publication Date
- 2025-03-07
- Estimated Expiration
- 2034-05-27
AI Technical Summary
In the existing motor heat dissipation structure, the injection pressure of the hollow shaft is small, which makes it difficult for the cooling oil to reach the space far away from the shaft and cannot effectively dissipate heat.
By changing both ends of the heat dissipation chamber into a tapered structure and opening a plurality of oil holes on the conical surface, the injection pressure is increased, so that the cooling oil can be injected to a further area to be cooled.
With the increase of injection speed and pressure, the cooling oil can reach the motor's to be cooled more effectively, improve the motor's heat dissipation efficiency and avoid overheating of the motor.
Smart Images
Figure CN222582221U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of motors, in particular to a motor heat dissipation structure. Background Art
[0002] New energy vehicles are currently developing at a high speed, and their drive motors are developing towards miniaturization, high power density, and lightweight. At present, the speed of the drive motor is generally tens of thousands of revolutions per minute. The extremely high speed will generate more heat during the operation of the motor. Therefore, high-speed motors require more efficient heat dissipation methods to keep their operating temperature within a controllable range to ensure the stability and reliability of the motor. Due to the limitations of water cooling and air cooling, the above two heat dissipation methods will not solve the heat dissipation problem of high-speed motors. At present, the common cooling method for high-speed motors is oil cooling: the motor shaft is a hollow shaft with a heat dissipation channel opened inside, and an oil hole is opened on the hollow shaft. The cooling oil enters the hollow shaft. Under the action of centrifugal force, the cooling oil will be thrown out from the oil hole along the radial direction of the internal cavity to cool the rotor core and other components. Since the heat dissipation channel is a cylindrical structure, the radial direction is relatively uniform, the speed and pressure of the cooling oil injection are small, resulting in a shorter injection distance, and the cooling oil is not easy to reach the space far away from the shaft. Utility Model Content
[0003] In view of the above-mentioned deficiencies in the prior art, the utility model provides a motor heat dissipation structure, which solves the problem of low oil injection pressure of the motor hollow shaft in the prior art.
[0004] In order to achieve the above purpose, the technical solution adopted by the utility model is:
[0005] A motor heat dissipation structure is provided, which comprises a rotating shaft, a rotor assembly and a stator assembly; the rotor assembly is sleeved outside the rotating shaft and arranged inside the stator assembly; an oil inlet chamber and a heat dissipation chamber are axially opened inside the rotating shaft, one end of the oil inlet chamber is connected to the outside of the rotating shaft, and the other end is connected to the heat dissipation chamber; both ends of the heat dissipation chamber are conical structures, and one end of the conical structure connected to the oil inlet chamber is its small end; and a plurality of oil holes penetrating to the outer wall of the rotating shaft are opened on the conical surfaces of the conical structures at both ends.
[0006] The beneficial effects of the utility model are as follows: the solution improves the shape of the two ends of the heat dissipation cavity into a conical structure, and the oil hole is opened on the conical surface, thereby increasing the oil injection pressure, so that the cooling oil can be sprayed to a farther area to be cooled. When the shaft rotates, the cooling oil inside the heat dissipation cavity is affected by the centrifugal force and will be sprayed outward. Compared with the cylindrical channel in the traditional structure, since the two ends of the heat dissipation cavity in this solution are conical structures, the internal space gradually narrows, the liquid is forced to accelerate during rotation, the centrifugal force increases, and the injection speed and pressure increase.
[0007] Furthermore, the oil holes include a plurality of first oil holes and a third oil hole for spraying the bearings and a plurality of second oil holes and a fourth oil hole for spraying the windings of the stator assembly; the first oil hole and the second oil hole are opened on a conical surface close to one end of the oil inlet chamber; the third oil hole and the fourth oil hole are opened on a conical surface away from one end of the oil inlet chamber. The cooling oil is sprayed from the first oil hole and the third oil hole to the bearing to ensure lubrication of the bearing. The cooling oil is sprayed from the second oil hole and the fourth oil hole to the winding to ensure heat dissipation of the winding and prevent overheating of the motor.
[0008] Furthermore, the cross section of the conical structure is circular, and the plurality of first oil holes, second oil holes, third oil holes and fourth oil holes are evenly arranged in an annular direction along the cross sections where they are located, so as to ensure even oil spraying when the shaft rotates.
[0009] Furthermore, the second oil hole and the fourth oil hole are straight oil holes perpendicular to the axis of the rotating shaft, and their outlet ends are close to the winding of the stator assembly. The inclined holes in the traditional structure are improved to straight holes, which reduces the difficulty of drilling the oil holes and shortens the processing time required for drilling.
[0010] Furthermore, the first oil hole and the third oil hole are arranged obliquely toward the bearing on the rotating shaft.
[0011] Furthermore, the rotor assembly includes a rotor core and a carbon fiber layer wound on the surface of the rotor core, and the carbon fiber layer is fixedly connected to the rotor core through a glue layer. By winding the carbon fiber layer, the power density of the motor is increased, making the high-speed operation of the motor safer and reducing the overall cost. BRIEF DESCRIPTION OF THE DRAWINGS
[0012] Figure 1 It is a schematic diagram of the heat dissipation structure of the motor;
[0013] Among them, 1. rotating shaft; 11. oil inlet chamber; 12. heat dissipation chamber; 13. first oil hole; 14. second oil hole; 15. third oil hole; 16. fourth oil hole; 2. rotor assembly; 21. carbon fiber layer; 3. stator assembly. DETAILED DESCRIPTION
[0014] The specific implementation methods of the utility model are described below to facilitate technical personnel in this technical field to understand the utility model, but it should be clear that the utility model is not limited to the scope of the specific implementation methods. For ordinary technical personnel in this technical field, as long as various changes are within the spirit and scope of the utility model defined and determined by the attached claims, these changes are obvious, and all utility model creations using the concept of the utility model are protected.
[0015] like Figure 1As shown, the motor heat dissipation structure of this solution includes a rotating shaft 1, a rotor assembly 2 and a stator assembly 3; the rotor assembly 2 is sleeved outside the rotating shaft 1 and arranged inside the stator assembly 3. The stator assembly 3 includes a stator core and a winding inserted in the stator core.
[0016] The shaft 1 is provided with an oil inlet chamber 11 and a heat dissipation chamber 12 along the axial direction. One end of the oil inlet chamber 11 is connected to the outside of the shaft 1, and the other end is connected to the heat dissipation chamber 12. The oil inlet chamber 11 is preferably a cylindrical structure; both ends of the heat dissipation chamber 12 are conical structures, and the middle is a cylindrical structure. Specifically, the shapes of the two ends are approximately Figure 1 The cone or funnel shown. One end of the conical structure connected to the oil inlet chamber 11 is the small end of the conical structure, that is, the diameter of the oil inlet chamber 11 is smaller than the diameter of the cylindrical structure in the middle of the heat dissipation chamber 12. The small ends of the two conical structures point to two opposite directions respectively. A plurality of oil holes penetrating the outer wall of the rotating shaft 1 are provided on the conical surfaces of the conical structures at both ends. The shapes of the conical structures at both ends may be consistent or inconsistent, especially the inclination of the conical surface and the axial length may be inconsistent.
[0017] This solution improves the two ends of the heat dissipation cavity 12 into a conical structure to increase the injection pressure. This is because when the shaft 1 rotates, the cooling oil inside the heat dissipation cavity 12 is affected by the centrifugal force and will be ejected outward. Compared with the cylindrical channel in the traditional structure, since the two ends of the heat dissipation cavity 12 in this solution are conical structures, the internal space gradually narrows, the liquid is forced to accelerate during rotation, the centrifugal force increases, and the injection speed and pressure increase.
[0018] Specifically, the oil holes include a plurality of first oil holes 13 and third oil holes 15 for spraying the bearings to ensure lubrication of the bearings, and also include a plurality of second oil holes 14 and fourth oil holes 16 for spraying the windings of the stator assembly 3 to ensure heat dissipation of the motor. The first oil hole 13 and the second oil hole 14 are opened on a conical surface close to one end of the oil inlet chamber 11; the third oil hole 15 and the fourth oil hole 16 are opened on a conical surface away from one end of the oil inlet chamber 11.
[0019] The two ends of the rotating shaft 1 are the non-spline end and the spline end, respectively. Both ends are provided with bearings and are close to the windings. The first oil hole 13 and the third oil hole 15 are respectively located on the conical surfaces at both ends. When the rotating shaft 1 rotates, the cooling oil is sprayed to the non-spline end bearing opening and the spline end bearing opening respectively. The second oil hole 14 and the fourth oil hole 16 spray to the non-spline end stator winding opening and the spline end stator winding opening respectively.
[0020] Preferably, the cross section of the tapered structure is circular, and the first oil holes 13, the second oil holes 14, the third oil holes 15 and the fourth oil holes 16 are uniformly arranged in an annular direction along their respective cross sections to ensure uniform oil injection when the shaft 1 rotates.
[0021] The second oil hole 14 and the fourth oil hole 16 are straight oil holes perpendicular to the axis of the rotating shaft 1, and their outlet ends are close to the winding of the stator assembly 3. The heat source of the motor when working is mainly concentrated in the stator core and the stator winding, so the outlet ends of the second oil hole 14 and the fourth oil hole 16 are preferably arranged close to the winding to ensure that the cooling oil is smoothly sprayed to the winding, ensure the heat dissipation of the winding, and avoid overheating of the motor.
[0022] Since the heat dissipation channel in the traditional structure is approximately cylindrical, its injection pressure is relatively low. In order to increase the injection pressure to a certain extent, the oil injection port for spraying the stator winding is usually set as an inclined hole inclined toward the winding. However, the inclined hole is difficult to process, the process is difficult, and the processing time is long. By using the conical surface, the oil injection pressure here can be guaranteed by opening a straight hole instead of an inclined hole, which reduces the difficulty of the drilling process for spraying the winding oil hole.
[0023] The first oil hole 13 and the third oil hole 15 are preferably arranged obliquely toward the bearing on the rotating shaft 1. Since the bearing is mounted on the rotating shaft 1, the outlet end of the oil hole is not easy to be arranged at the bearing, so the oil hole for spraying the bearing preferably needs an inclined spray angle to ensure that it can be sprayed smoothly to the bearing. Although the first oil hole 13 and the third oil hole 15 are still oblique holes, this solution reduces the number of oil holes that need to be drilled oblique holes, and can reduce the difficulty of the drilling process of some oil holes, thereby shortening the total processing time required for drilling.
[0024] High-speed drive motors not only require higher heat dissipation efficiency, but also need to improve power density to ensure its safety during high-speed operation. In one embodiment of the present scheme, the rotor assembly 2 preferably includes a rotor core and a carbon fiber layer 21 wound on the surface of the rotor core, and the carbon fiber layer 21 is fixedly connected to the rotor core through a glue layer. The high-speed motor with a rotation speed of 14000-18000rpm has reached the tensile strength limit of the silicon steel sheet. At present, the strength limit of the rotor silicon steel sheet is about 400Mpa. If the speed is increased, the motor rotor will burst and cause safety problems. However, it is difficult to control the cost to improve the tensile strength of the silicon steel sheet itself. Therefore, the rotor strength can be improved by winding the carbon fiber layer 21 to prevent the rotor from bursting during high-speed operation due to the insufficient strength of the rotor silicon steel sheet to resist stress, thereby enabling the motor to have a higher rotation speed, improve the power density of the motor, make the motor run at high speed safer, and reduce the overall cost.
[0025] The general winding steps are as follows: immerse the strip-shaped carbon fiber in the resin liquid, and wrap the resin on the carbon fiber so that the carbon fiber can adhere to the rotor core. Use a special winding device to apply a certain preload to wind the carbon fiber onto the rotor. During the winding process, it is necessary to ensure that the direction and number of layers of the carbon fiber meet the design requirements, while maintaining a certain tension and tightness. After the carbon fiber winding is completed, the resin needs to be cured, usually by chemical curing. The cured resin can firmly adhere the carbon fiber to the rotor core to form a strong composite material structure.
[0026] In summary, the present solution improves the two ends of the heat dissipation cavity 12 into a conical structure, which can increase the injection pressure.
Claims
1. A motor heat dissipation structure, characterized in that: It comprises a rotating shaft (1), a rotor assembly (2) and a stator assembly (3); the rotor assembly (2) is sleeved outside the rotating shaft (1) and arranged inside the stator assembly (3); An oil inlet chamber (11) and a heat dissipation chamber (12) are axially provided inside the rotating shaft (1); one end of the oil inlet chamber (11) is connected to the outside of the rotating shaft (1), and the other end is connected to the heat dissipation chamber (12); both ends of the heat dissipation chamber (12) are conical structures, and the end of the conical structure connected to the oil inlet chamber (11) is the small end; and a plurality of oil holes penetrating the outer wall of the rotating shaft (1) are provided on the conical surfaces of the conical structures at both ends.
2. The motor heat dissipation structure according to claim 1, characterized in that: The oil holes include a first oil hole (13), a third oil hole (15) of a plurality of injection bearings and a second oil hole (14) and a fourth oil hole (16) of a plurality of windings of an injection stator assembly (3); the first oil hole (13) and the second oil hole (14) are opened on a conical surface close to one end of the oil inlet chamber (11); and the third oil hole (15) and the fourth oil hole (16) are opened on a conical surface away from one end of the oil inlet chamber (11).
3. The motor heat dissipation structure according to claim 2, characterized in that: The cross section of the tapered structure is circular, and a plurality of first oil holes (13), second oil holes (14), third oil holes (15) and fourth oil holes (16) are uniformly arranged in an annular direction along their respective cross sections.
4. The motor heat dissipation structure according to claim 3, characterized in that: The second oil hole (14) and the fourth oil hole (16) are straight oil holes perpendicular to the axis of the rotating shaft (1), and their outlet ends are close to the winding of the stator assembly (3).
5. The motor heat dissipation structure according to claim 3, characterized in that: The first oil hole (13) and the third oil hole (15) are arranged obliquely toward the bearing on the rotating shaft (1).
6. The motor heat dissipation structure according to claim 1, characterized in that: The rotor assembly (2) comprises a rotor core and a carbon fiber layer (21) wound around the surface of the rotor core, wherein the carbon fiber layer (21) is fixedly connected to the rotor core via a glue layer.