Cooling oil system applied to motor
By designing a motor cooling oil system that includes an oil cooler, an oil pump and a spindle oil path, the problems of uneven cooling oil flow and large space occupation are solved, achieving efficient cooling of the motor and efficient use of space.
Patent Information
- Application Number
- CN202420262497.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-02-02
- Publication Date
- 2025-01-21
- Estimated Expiration
- 2034-02-02
AI Technical Summary
In the existing motor cooling oil system, the cooling oil lacks a fixed flow path in the cavity, causing the cooling oil near the oil pump area to flow faster, while the cooling oil far away from the oil pump area is subjected to a small suction force, which is retained for a long time and cannot effectively dissipate heat. . At the same time, the oil cooling system takes up a lot of space, which affects the design and layout of motor components.
A cooling oil system for motors is designed, including an oil cooler, an oil pump and a mandrel oil path. The oil pump is arranged between the motor housing and the mandrel. The mandrel oil path extends along the axial direction of the mandrel to form a complete and effective Sequential cooling oil flow path. A cycloidal gear pump is used as the power component of the cooling oil circulation. The design of the cycloidal gear pump does not occupy a lot of space, and the rotation speed is slow and the kinetic energy requirement is small.
It achieves the uniform flow and return of cooling oil between various components of the motor, avoids the problem of cooling oil retention, and improves the cooling effect of the motor. At the same time, due to the high space efficiency of the pump design, it does not occupy too much internal space of the motor.
Smart Images
Figure CN222381473U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of electric vehicles, and in particular to a cooling oil system applied to a motor. Background Art
[0002] During the driving of electric vehicles, their power components, namely the motors, face complex working conditions. The motor working conditions frequently switch between multiple modes, which then causes the motor windings to overheat. Whether based on the consideration of the current operating performance of the motor or the consideration of the motor's service life, providing effective cooling for the entire motor is one of the indispensable means.
[0003] There are many cooling methods available for electric vehicle motors, among which oil cooling using cooling oil is one of the most widely used methods. The heat generated by the operation of the motor is carried to the cooling system through the cooling oil, and heat is exchanged with the external environment, thereby realizing the process of heat dissipation of the motor to the outside world. However, in the implementation process, the oil cooling system still faces a series of problems. The cooling oil enters the cavity defined by the motor housing through the oil pump and circulates in the cavity, but the cooling oil does not have a fixed flow path in the cavity. As a result, the cooling oil close to the oil pump is subjected to a larger suction force and returns to the oil cooler for heat exchange faster, while the cooling oil relatively far from the oil pump is subjected to a smaller suction force and stays in place for a long time, absorbing the heat generated by the various components of the motor, but cannot return to the oil cooler for heat exchange. In addition, configuring the oil cooling system in the motor housing requires a certain amount of space, and the design layout of the various components of the motor has occupied most of the space in the motor housing. How to provide highly covered cooling for the motor without hindering the normal operation of the motor is an urgent problem to be solved. Summary of the invention
[0004] In order to overcome at least one of the defects of the prior art described above, the present application proposes a cooling oil system for a motor, wherein the motor comprises a motor housing, a core shaft, a rotor, a stator and an end plate, and is characterized in that the cooling oil system comprises:
[0005] an oil cooler that draws cooling oil from a cavity defined by the motor housing and cools it;
[0006] an oil pump disposed between the motor housing and the spindle, comprising an oil pump inlet and an oil pump outlet, wherein the oil pump inlet is in fluid communication with the oil cooler;
[0007] The spindle oil path is in fluid communication with the oil pump outlet and extends axially inside the spindle.
[0008] In one embodiment, the oil cooling system further includes an oil inlet, and the oil inlet is arranged on the outer surface of the motor housing.
[0009] In another embodiment, the oil cooling system further comprises a grooved oil path arranged on the inner surface of the motor housing, comprising a first end and a second end, wherein the first end is fluidically connected to the oil inlet, and the second end is fluidically connected to the oil cooler.
[0010] In yet another embodiment, the groove-shaped oil path extends on the inner surface of the motor housing in the axial direction and the circumferential direction of the motor.
[0011] In yet another embodiment, the grooved oil path has a depth of 3 mm and a width of 18 mm.
[0012] In yet another embodiment, the oil cooling system further includes a rotor oil path disposed in the rotor of the motor and extending in a radial direction of the motor; the rotor oil path is in fluid communication with the spindle oil path.
[0013] In yet another embodiment, the oil cooling system further includes a stator oil path disposed in a stator of the motor; the stator oil path is in fluid communication with the rotor oil path.
[0014] In yet another embodiment, the stator of the motor has iron core end plates on both sides along the axial direction of the motor, and each of the iron core end plates is provided with a plurality of through holes so that cooling oil can enter and exit the stator through the plurality of through holes.
[0015] In yet another embodiment, the oil pump is in the form of a gerotor gear pump.
[0016] In yet another embodiment, the number of teeth of the outer rotor gear of the cycloid gear pump is one more than the number of teeth of the inner rotor gear.
[0017] The cooling oil system applied to the motor of the present application constructs a complete and orderly cooling oil flow path. On the one hand, the cooling oil can reach various parts of the motor to absorb heat after flowing out of the oil pump. On the other hand, the design of the cooling oil flow path allows the cooling oil to flow to any part / position of the motor and return to the oil cooler by the suction force of the oil pump, without the above-mentioned problem that the cooling oil far away from the oil pump is subject to a smaller suction force and stays in the original place for a long time. The cooling oil system of the present application uses a cycloid gear pump as the power component of the cooling oil circulation. The cycloid gear pump does not need to occupy a large space like a centrifugal pump or a plunger pump, and the rotation speed of the inner / outer rotor gear of the cycloid gear pump is relatively slow. In other words, its kinetic energy demand during normal operation is relatively small. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Figure 1 A schematic structural diagram of a cooling oil system applied to a motor according to an embodiment of the present application is shown;
[0019] Figure 2 Shows Figure 1 The schematic cross-sectional view of the cooling oil system along the BB section line is shown;
[0020] Figure 3 A schematic diagram of the structure of an oil pump according to an embodiment of the present application is shown; and
[0021] Figure 4 A schematic structural diagram of a core end plate according to an embodiment of the present application is shown. DETAILED DESCRIPTION
[0022] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.
[0023] It should be noted that the illustrations provided in this embodiment only illustrate the basic concept of the present application in a schematic manner, and therefore the drawings only show components related to the present application rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.
[0024] The structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification so as to facilitate understanding and reading by persons familiar with this technology. They are not used to limit the conditions under which this application can be implemented, and therefore have no substantive technical significance. Any structural modification, change in proportion or adjustment of size, without affecting the effects and purposes that can be achieved by this application, should still fall within the scope of the technical contents disclosed in this application.
[0025] The directions or positional relationships indicated by the terms "upper", "lower", "left", "right", "middle", "longitudinal", "lateral", "horizontal", "inner", "outer", "radial", "circumferential" and the like in this specification are based on the directions or positional relationships shown in the drawings and are only for the convenience of simplifying the description. They do not indicate or imply that the devices or elements referred to must have a specific direction, be constructed and operate in a specific direction, and therefore cannot be understood as limiting the present application. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.
[0026] like Figure 1-2As shown, the cooling oil system applied to the motor of the present application includes an oil cooler 1, an oil pump 2, and a spindle oil path 3 which are fluidically connected in sequence. The oil cooler 1 is configured to utilize the suction force of the oil pump 2 which is fluidically connected thereto to draw cooling oil from the cavity defined by the motor housing and cool it. The oil pump 2 is arranged between the motor housing and the spindle, and includes an oil pump inlet and an oil pump outlet, wherein the oil pump inlet is fluidically connected to the aforementioned oil cooler 1. Next, the spindle oil path 3 is fluidically connected to the oil pump outlet and extends axially inside the spindle.
[0027] Furthermore, the oil cooling system of the present application also includes an oil inlet 4 and a grooved oil path 5. The oil inlet 4 is disposed on the outer surface of the motor housing. The grooved oil path 5 is arranged on the inner surface of the motor housing, and includes a first end and a second end, wherein the first end is fluidically connected to the oil inlet 4, and the second end is fluidically connected to the oil cooler 1. Thus, when the user or maintenance personnel uses the prior art to determine that the cooling oil in the motor is insufficient, the cooling oil system can be injected through the oil inlet 4 to supplement the amount of cooling oil consumed by the frequent operation of the motor. On the other hand, it can be seen that the cooling oil entering the oil cooler 1 for heat exchange includes not only the circulating cooling oil drawn from the cavity, but also the newly added cooling oil received from the oil inlet 4.
[0028] Since the grooved oil path 5 is located on the inner surface of the motor housing, the grooved oil path 5 is designed to extend along the axial direction and circumferential direction of the motor on the inner surface for the sake of convenience in processing / manufacturing. In this way, both the axial extension section and the circumferential extension section of the grooved oil path 5 are convenient for machining using processing equipment. Preferably, the grooved oil path 5 is provided as a groove with a square cross section and a depth of 3 mm and a width of 18 mm. More preferably, the motor housing and the stator are matched in a clearance fit, thereby reserving sufficient space for the grooved oil path 5.
[0029] Further, the oil cooling system also includes a rotor oil path 6, which is arranged in the rotor of the motor and extends in the radial direction of the motor. The rotor oil path 6 is in fluid communication with the core shaft oil path 3. Specifically, the core shaft of the motor is provided with a plurality of holes, and the cooling oil in the core shaft oil path 3 flows to the rotor oil path 6 through these holes. Preferably, the oil cooling system includes six rotor oil paths 6 extending in the radial direction of the motor, and these rotor oil paths 6 are arranged around the core shaft of the motor at equal angular distances from each other; of course, other numbers of rotor oil paths 6 are also feasible.
[0030] Further, the oil cooling system further includes a stator oil path 7, which is arranged in the stator of the motor. The stator oil path 7 is in fluid communication with the rotor oil path 6 so as to receive cooling oil from the rotor oil path 6. The stator oil path 7 can extend in the axial direction and circumferential direction of the motor in the stator of the motor, so that the cooling oil can traverse the stator to absorb heat from all parts of the stator.
[0031] Combination Figure 4 The stator of the motor has core end plates 8 on both sides along the axial direction of the motor, and each core end plate 8 is provided with a plurality of through holes 81 so that cooling oil can enter and exit the stator through these through holes 81. It can be imagined that the cavity defined by the motor housing also contains cooling oil, and the cooling oil will have different local temperatures due to the different temperatures of different parts of the motor. Such temperature differences of the cooling oil at different positions will cause the cooling oil to flow between each other. By providing these through holes 81, the cooling oil can flow from the stator to the cavity, and vice versa, which promotes the circulation of the cooling oil and the absorption of heat.
[0032] Back to Figure 3 , which shows a schematic diagram of the structure of the oil pump according to an embodiment of the present application. In this embodiment, the oil pump 2 is in the form of a cycloidal gear pump 2. The number of teeth of the outer rotor gear 21 of the cycloidal gear pump 2 is one more than the number of teeth of the inner rotor gear 22. When the outer rotor gear 21 rotates around the center, it drives the inner rotor gear 22 to rotate in the same direction around the center of the inner rotor. At this time, the sealed volume formed by the tooth tops of the inner rotor and the tooth valleys of the outer rotor gradually expands as the rotor rotates, thus forming a local vacuum, and the oil is sucked into the sealed cavity from the inlet of the oil pump until the closed volume is maximum, at which time the oil suction is completed. When the outer / inner rotor gears 21 and 22 continue to rotate, the sealed volume filled with oil gradually decreases, the oil is squeezed, and the oil is discharged through the oil pump outlet. When the other teeth of the inner rotor gear 22 are all meshed with the tooth recesses of the outer rotor gear 21, the oil is pressed. For each rotation of the inner rotor gear 22, each sealed volume formed by the tooth tops of the inner rotor and the tooth valleys of the outer rotor completes oil suction and oil pressure once. When the inner rotor gear 22 rotates continuously, the cycloid gear pump 2 completes the oil suction and discharge work.
[0033] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0034] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.
Claims
1. A cooling oil system for a motor, wherein the motor comprises a motor housing, a core shaft, a rotor, a stator and an end plate, characterized in that: The cooling oil system comprises: an oil cooler that draws cooling oil from a cavity defined by the motor housing and cools it; an oil pump disposed between the motor housing and the spindle, comprising an oil pump inlet and an oil pump outlet, wherein the oil pump inlet is in fluid communication with the oil cooler; The spindle oil path is in fluid communication with the oil pump outlet and extends axially inside the spindle.
2. The cooling oil system for a motor according to claim 1, characterized in that: It also includes an oil inlet, which is arranged on the outer surface of the motor housing.
3. The cooling oil system for a motor according to claim 2, characterized in that: The motor also includes a groove-shaped oil path disposed on the inner surface of the motor housing, the groove-shaped oil path including a first end and a second end, wherein the first end is fluidically connected to the oil inlet, and the second end is fluidically connected to the oil cooler.
4. The cooling oil system for a motor according to claim 3, characterized in that: The groove-shaped oil path extends on the inner surface of the motor housing in the axial direction and the circumferential direction of the motor.
5. The cooling oil system for a motor according to claim 3 or 4, characterized in that: The groove-shaped oil path had a depth of 3 mm and a width of 18 mm.
6. The cooling oil system for a motor according to claim 1, characterized in that: The motor also includes a rotor oil path, which is arranged in the rotor of the motor and extends in the radial direction of the motor; the rotor oil path is in fluid communication with the core shaft oil path.
7. The cooling oil system for a motor according to claim 6, characterized in that: The motor also includes a stator oil path disposed in the stator of the motor; the stator oil path is in fluid communication with the rotor oil path.
8. The cooling oil system for a motor according to claim 7, characterized in that: The stator of the motor has iron core end plates on both sides along the axial direction of the motor, and each of the iron core end plates is provided with a plurality of through holes so that cooling oil can enter and exit the stator through the plurality of through holes.
9. The cooling oil system for a motor according to claim 1, characterized in that: The oil pump is in the form of a cycloidal gear pump.
10. The cooling oil system for a motor according to claim 9, characterized in that: The number of teeth of the outer rotor gear of the cycloid gear pump is one more than the number of teeth of the inner rotor gear.