Cooling structure for motor reducer assembly of new energy vehicle

Abstract

The invention provides a cooling structure for a motor reducer assembly of a new energy vehicle, which comprises a motor rotating shaft and a reducer input shaft, a first cooling water channel is arranged in the motor rotating shaft, a second cooling water channel is arranged in the reducer input shaft, and the right end of the motor rotating shaft is connected with the left end of the reducer input shaft. The first cooling water channel and the second cooling water channel are coaxial and are communicated with each other; the left end of the motor rotating shaft is rotatably arranged in a shaft hole of the motor rear end cover, the motor rear end cover is provided with a water inlet connector pipe, and the left end of the shaft hole of the motor rear end cover is provided with a first communication cavity for communicating the water inlet connector pipe with the first cooling water channel; the right end of the speed reducer input shaft is rotationally arranged in a shaft hole of the speed reducer rear shell, a water outlet connector pipe is arranged on the speed reducer rear shell, and a second communicating cavity used for communicating the water outlet connector pipe with the second cooling water channel is formed in the right end of the shaft hole of the speed reducer rear shell. The motor and the speed reducer can obtain a good cooling effect, the cost is reduced, and popularization is facilitated.

Description

Technical Field

[0001] The present invention belongs to the technical field of new energy vehicles, and in particular relates to a cooling structure for a motor reducer assembly of a new energy vehicle. Background Art

[0002] The electric drive system is the core component of new energy electric vehicles, generally including three major components: drive motor, motor controller, and reducer. At present, electric vehicles have higher and higher requirements for the power and torque of the electric drive system, while also requiring light weight and small size, which requires the electric drive system to have better heat dissipation performance.

[0003] There are three existing heat dissipation methods for electric drive systems:

[0004] Natural air cooling: The natural wind blows on the shell surface to dissipate heat when the vehicle is running. This solution is generally used in the electric drive system of economical low-range electric vehicles. The advantage is low cost, but the disadvantage is low heat dissipation performance, especially not conducive to the heat dissipation of the rotor inside the motor;

[0005] Liquid cooling: Water channels are designed on the motor housing and the controller housing, and coolant is passed through the channels to remove the heat transferred from the motor to the housing. However, it is not conducive to the heat dissipation of the rotor and other components inside the motor. This solution is currently the most common cooling method and is generally used in low-end and mid-end models.

[0006] Oil cooling + liquid cooling: The motor and reducer share the same oil circuit and use oil cooling to dissipate heat. The heat of the oil is taken away by the coolant circulating in the heat exchanger. This solution is widely used in high-end vehicle electric drive systems. Its disadvantage is that it requires a complex motor oil circuit design, adding oil pumps, oil filters, oil circuits and other structures, and requires precise lubrication simulation and testing to ensure the heat dissipation performance of key parts of the motor, thereby increasing the cost of components and testing, and extending the development cycle. It is generally used in high-end models and is not conducive to popularization in mid- and low-end models.

[0007] Therefore, how to design a cooling structure for a motor reducer assembly of a new energy vehicle so that the motor and reducer can obtain a better cooling effect has become a technical problem that technical personnel in this field urgently need to solve. Summary of the invention

[0008] The purpose of the present invention is to provide a cooling structure for a motor reducer assembly of a new energy vehicle to solve the above-mentioned technical problems in the prior art.

[0009] To achieve the above object, the present invention provides the following technical solutions:

[0010] A cooling structure for a motor reducer assembly of a new energy vehicle comprises a motor shaft and a reducer input shaft, wherein a first cooling water channel is arranged in the motor shaft, and a second cooling water channel is arranged in the reducer input shaft, the right end of the motor shaft is connected to the left end of the reducer input shaft, and the first cooling water channel is coaxial with and connected to the second cooling water channel; the left end of the motor shaft is rotatably arranged in the axial hole of the rear end cover of the motor, and a water inlet interface pipe is arranged on the rear end cover of the motor, and the left end of the axial hole of the rear end cover of the motor has a first connecting cavity for connecting the water inlet interface pipe with the first cooling water channel; the right end of the reducer input shaft is rotatably arranged in the axial hole of the reducer rear housing, and a water outlet interface pipe is arranged on the reducer rear housing, and the right end of the axial hole of the reducer rear housing has a second connecting cavity for connecting the water outlet interface pipe with the second cooling water channel.

[0011] Preferably, an annular groove is arranged on the outer circumferential surface of the right end of the motor shaft, and a sealing ring is arranged in the annular groove.

[0012] Preferably, the left end of the reducer input shaft is rotatably set in the axial hole of the reducer front housing, and the right end of the motor shaft is rotatably set in the right end axial hole of the motor housing; a third cooling water channel is circumferentially arranged around the motor housing, and a water inlet pipe connected to one end of the third cooling water channel and a water outlet pipe connected to the other end of the third cooling water channel are arranged on the motor housing.

[0013] Preferably, a motor front bearing and a motor front oil seal are arranged in sequence from left to right between the right end of the motor shaft and the inner wall of the right end shaft hole of the motor housing, and a reducer front oil seal and a reducer front bearing are arranged in sequence from left to right between the left end of the reducer input shaft and the inner wall of the shaft hole of the reducer front housing.

[0014] Preferably, the water inlet interface pipe is connected to a first water inlet pipeline, and a first switch valve is provided on the first water inlet pipeline.

[0015] Preferably, a second water inlet pipeline is provided on the water inlet pipe, and a second switch valve is provided on the second water inlet pipeline.

[0016] Preferably, a connecting pipeline is provided between the water outlet interface pipe and the water inlet pipe, and a third switch valve is provided on the connecting pipeline.

[0017] Preferably, the water outlet interface pipe is connected to a water outlet pipeline, and a fourth switch valve is provided on the water outlet pipeline.

[0018] Preferably, a motor rear oil seal and a motor rear bearing are sequentially arranged from left to right between the left end of the motor shaft and the inner wall of the shaft hole of the rear end cover of the motor.

[0019] Preferably, a reducer rear bearing and a reducer rear oil seal are sequentially arranged from left to right between the right end of the reducer input shaft and the inner wall of the shaft hole of the reducer rear housing.

[0020] The beneficial effects of the present invention are:

[0021] The cooling structure for the motor reducer assembly of a new energy vehicle of the present invention, when in use, can cool the inside of the motor and the reducer by means of the coolant flowing through the first cooling water channel and the second cooling water channel, so that the motor rotor and the reducer input shaft and the parts nearby can obtain a better cooling effect, thereby improving the heat dissipation performance of the motor and the reducer; at the same time, it omits the oil pump, oil filter and other components in the oil cooling heat dissipation method of the prior art, thereby saving costs and being conducive to popularization. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the embodiments, and further describe the specific embodiments of the present invention in detail in conjunction with the drawings, wherein

[0023] Figure 1 A schematic diagram of a cooling structure for a motor reducer assembly of a new energy vehicle provided by an embodiment of the present invention;

[0024] Figure 2 A schematic diagram of a rear end cover of a motor provided in an embodiment of the present invention;

[0025] Figure 3 A cross-sectional view of a rear end cover of a motor provided by an embodiment of the present invention;

[0026] Figure 4 A schematic diagram of a motor shaft provided in an embodiment of the present invention;

[0027] Figure 5 A cross-sectional view of a motor shaft provided by an embodiment of the present invention;

[0028] Figure 6 A schematic diagram of a motor housing provided by an embodiment of the present invention;

[0029] Figure 7 A cross-sectional view of a motor housing provided by an embodiment of the present invention;

[0030] Figure 8 A schematic diagram of a reducer input shaft provided in an embodiment of the present invention;

[0031] Fig. 9 A cross-sectional view of a reducer input shaft provided by an embodiment of the present invention;

[0032] Fig.10 A schematic diagram of a rear housing of a reducer provided in an embodiment of the present invention;

[0033] Fig.11 A cross-sectional view of a rear housing of a reducer provided in an embodiment of the present invention;

[0034] Fig.12 A schematic diagram of a sealing ring provided in an embodiment of the present invention;

[0035] Fig.13 A schematic diagram of a water outlet interface pipe and a water inlet pipe provided in an embodiment of the present invention being connected via a connecting pipeline.

[0036] Markings in the accompanying drawings:

[0037] 11. motor shaft, 12. first cooling water channel, 13. annular groove;

[0038] 21. reducer input shaft, 22. second cooling water channel;

[0039] 31. Motor rear end cover, 32. Water inlet interface pipe, 33. Motor rear oil seal,

[0040] 34. Motor rear bearing; 41. Reducer rear housing; 42. Water outlet pipe;

[0041] 43. Reducer rear bearing, 44. Reducer rear oil seal; 51. Motor housing,

[0042] 52. The third cooling water channel, 53. The front bearing of the motor, 54. The front oil seal of the motor,

[0043] 55, water inlet pipe, 56, water outlet pipe;

[0044] 61. Reducer front housing, 62. Reducer front oil seal, 63. Reducer front bearing;

[0045] 71. Sealing ring; 81. First water inlet pipe; 82. Connecting pipe. DETAILED DESCRIPTION

[0046] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that the relative arrangement of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present invention unless otherwise specifically stated.

[0047] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses.

[0048] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered as part of the specification.

[0049] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0050] like Figures 1 to 13 As shown, an embodiment of the present invention provides a cooling structure for a motor reducer assembly of a new energy vehicle, which includes a motor shaft 11 and a reducer input shaft 21, wherein a first cooling water channel 12 is arranged in the motor shaft, and a second cooling water channel 22 is arranged in the reducer input shaft, the right end of the motor shaft is connected to the left end of the reducer input shaft, and the first cooling water channel 12 is coaxial with and connected to the second cooling water channel 22; the left end of the motor shaft is rotatably arranged in the axial hole of the rear end cover 31 of the motor, and a water inlet interface pipe 32 is arranged on the rear end cover of the motor, and the left end of the axial hole of the rear end cover of the motor has a first connecting cavity for connecting the water inlet interface pipe with the first cooling water channel; the right end of the reducer input shaft is rotatably arranged in the axial hole of the reducer rear housing 41, and a water outlet interface pipe 42 is arranged on the reducer rear housing 41, and the right end of the axial hole of the reducer rear housing has a second connecting cavity for connecting the water outlet interface pipe with the second cooling water channel.

[0051] The cooling structure for the motor reducer assembly of a new energy vehicle provided in an embodiment of the present invention can, when in use, cool the inside of the motor and the reducer by means of the coolant flowing through the first cooling water channel and the second cooling water channel, so that the motor rotor and the reducer input shaft and the components nearby can obtain a better cooling effect, thereby improving the heat dissipation performance of the motor and the reducer; at the same time, it omits components such as the oil pump and the oil filter in the oil cooling heat dissipation method of the prior art, saves the cost of components and the test cost, shortens the development cycle, and is conducive to popularization in mid- and low-end models.

[0052] Furthermore, an annular groove 13 is provided on the outer circumferential surface of the right end of the motor shaft 11, and a sealing ring 71 is provided in the annular groove. With this solution, the sealing ring can play a better sealing role between the motor shaft and the reducer input shaft, seal the coolant and prevent leakage. It can be understood that the right end of the motor shaft is arranged inside the left end of the reducer input shaft.

[0053] Specifically, the left end of the reducer input shaft 21 is rotatably disposed in the shaft hole of the reducer front housing 61, and the right end of the motor shaft 11 is rotatably disposed in the right end shaft hole of the motor housing 51; a third cooling water channel 52 is disposed around the circumference of the motor housing, and a water inlet pipe 55 connected to one end of the third cooling water channel and a water outlet pipe 56 connected to the other end of the third cooling water channel are disposed on the motor housing. With this solution, supplying coolant into the third cooling water channel can achieve a better cooling effect on the motor housing, thereby improving the heat dissipation performance of the motor.

[0054] Preferably, a motor front bearing 53 and a motor front oil seal 54 are sequentially arranged from left to right between the right end of the motor shaft and the inner wall of the right end shaft hole of the motor housing, and a reducer front oil seal 62 and a reducer front bearing 63 are sequentially arranged from left to right between the left end of the reducer input shaft and the inner wall of the shaft hole of the reducer front housing, thereby conveniently realizing the rotation setting of the right end of the motor shaft in the right end shaft hole of the motor housing and the rotation setting of the left end of the reducer input shaft in the shaft hole of the reducer front housing, and at the same time having a better sealing effect.

[0055] Specifically, the first cooling water channel 12 is located at the middle position of the motor shaft 11 , and the second cooling water channel 22 is located at the middle position of the reducer input shaft 21 .

[0056] Furthermore, the water inlet interface pipe 32 is connected to a first water inlet pipeline 81, and a first switch valve is arranged on the first water inlet pipeline. With this solution, the first switch valve can be used to conveniently open and close the first water inlet pipeline as needed.

[0057] Specifically, the water inlet pipe is provided with a second water inlet pipeline, and the second water inlet pipeline is provided with a second switch valve. With this solution, the second water inlet pipeline can be conveniently opened and closed by the second switch valve.

[0058] In an embodiment provided by the present invention, a connecting pipe 82 is provided between the water outlet interface pipe 42 and the water inlet pipe 55, and a third switch valve is provided on the connecting pipe 82. With this solution, the connecting pipe can be conveniently opened and closed by the third switch valve, so that the first cooling water channel and the second cooling water channel can be controlled in series with the third cooling water channel as required.

[0059] Specifically, the water outlet interface pipe is connected to a water outlet pipeline, and a fourth switch valve is arranged on the water outlet pipeline, so that the water outlet pipeline can be conveniently opened and closed by the fourth switch valve.

[0060] In specific use, the cooling channel composed of the first cooling water channel 12 and the second cooling water channel 22 and the third cooling water channel 52 can be connected in parallel or in series, and the above cooling channel and the third cooling water channel can be closed or opened as needed to achieve optimal energy consumption control, specifically:

[0061] When the vehicle is running at low speed and high torque, the motor stator winding generates a lot of heat, the motor housing accumulates a lot of heat, and the motor rotor temperature is relatively low. At this time, only the third cooling water channel on the motor housing can be supplied with coolant;

[0062] When the vehicle is running at high speed, the temperature of the motor rotor is high. The third switch valve is opened, the fourth switch valve is closed, and the cooling channel is connected in series with the third cooling water channel through the connecting pipeline. The coolant first flows into the water inlet interface pipe through the first water inlet pipeline, and then enters the first cooling water channel and the second cooling water channel, and then enters the third cooling water channel through the connecting pipeline through the water inlet pipe, and then flows out from the water outlet pipe into the vehicle thermal management system. In this way, the coolant first enters the motor shaft to reduce the temperature inside the motor and the reducer, which is more conducive to protecting the motor rotor;

[0063] In other working conditions, the cooling channel and the third cooling water channel can be connected in parallel as needed, that is, the third switch valve is closed, and the first switch valve, the second switch valve and the fourth switch valve are all opened to supply coolant to the cooling channel and the third cooling water channel respectively;

[0064] Under extremely cold conditions, when the vehicle stops using motor auxiliary heating, the motor is stationary but can generate heat to heat the coolant. After the coolant flows through the battery water pipe, it can heat the battery cells to solve the problem of low battery charging efficiency at low temperatures. At this time, the cooling channel and the third cooling water channel can be connected in parallel or series to maximize the transfer of motor heat to the coolant, thereby heating the battery cells. This can solve the problem that only the third cooling water channel on the motor housing can take away the motor heat and the battery cell heating efficiency is low. It can also solve the problem that when an oil-cooled motor uses this function, it needs to transfer heat to the lubricating oil, and the lubricating oil then transfers heat to the coolant through a heat exchanger, and then heats the battery cells with low heat exchange efficiency.

[0065] Furthermore, a motor rear oil seal 33 and a motor rear bearing 34 are sequentially arranged from left to right between the left end of the motor shaft and the inner wall of the shaft hole of the motor rear end cover. With this solution, the motor rear bearing 34 can support the left end of the motor shaft, and the motor rear oil seal 33 can be used for sealing to prevent coolant from entering the motor housing.

[0066] Specifically, a reducer rear bearing 43 and a reducer rear oil seal 44 are sequentially arranged from left to right between the right end of the reducer input shaft and the inner wall of the shaft hole of the reducer rear housing. With this solution, the reducer rear bearing 43 can support the right end of the reducer input shaft, and the reducer rear oil seal 44 can be used for sealing to prevent the coolant from entering the reducer rear housing.

[0067] It is understandable that although the use of oil cooling to cool the inside of the motor can achieve a cooling effect, it requires the addition of oil pumps, oil pipes, complex internal oil circuit design and a large amount of test verification, which is not conducive to cost reduction and rapid development and maturity, nor is it conducive to popularization on all types of electric vehicles.

[0068] The present invention designs a third cooling water channel on the motor housing to cool the motor, and injects lubricating oil into the reducer to lubricate and cool the reducer. In addition, a cooling channel, namely a first cooling water channel and a second cooling water channel, which are connected to the motor and the reducer, is added to cool the inside of the motor and the reducer, thereby improving the heat dissipation performance of the electric drive system. In addition, the motor shaft and the motor housing are both cooled by coolant cooling. Compared with the existing motor internal oil cooling solution, it can better save the oil pump, oil filter and other components, and the cost is lower. In addition, the above-mentioned cooling channel and the third cooling water channel can be connected in parallel or in series, and can also be closed or opened as needed, so as to achieve better thermal management performance of the whole vehicle, and can achieve faster heating of the battery cells, so that the battery cells in a low temperature environment can be quickly heated up, and the charging efficiency of the battery is improved.

[0069] Although some specific embodiments of the present invention have been described in detail by way of example, it will be appreciated by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the present invention. It will be appreciated by those skilled in the art that the above embodiments may be modified without departing from the scope and spirit of the present invention. The scope of the present invention is defined by the appended claims.

Claims

1. A cooling structure for a motor reducer assembly of a new energy vehicle, characterized in that: It includes a motor shaft and a reducer input shaft, a first cooling water channel is arranged in the motor shaft, a second cooling water channel is arranged in the reducer input shaft, the right end of the motor shaft is connected to the left end of the reducer input shaft, the first cooling water channel is coaxial with the second cooling water channel and is connected; the left end of the motor shaft is rotatably arranged in the axial hole of the rear end cover of the motor, a water inlet interface pipe is arranged on the rear end cover of the motor, and the left end of the axial hole of the rear end cover of the motor has a first connecting cavity for connecting the water inlet interface pipe with the first cooling water channel; the right end of the reducer input shaft is rotatably arranged in the axial hole of the reducer rear housing, a water outlet interface pipe is arranged on the reducer rear housing, and the right end of the axial hole of the reducer rear housing has a second connecting cavity for connecting the water outlet interface pipe with the second cooling water channel.

2. The cooling structure for the motor reducer assembly of a new energy vehicle according to claim 1, characterized in that: An annular groove is arranged on the outer circumferential surface of the right end of the motor shaft, and a sealing ring is arranged in the annular groove.

3. The cooling structure for the motor reducer assembly of a new energy vehicle according to claim 1, characterized in that: The left end of the reducer input shaft is rotatably set in the axial hole of the reducer front housing, and the right end of the motor shaft is rotatably set in the right end axial hole of the motor housing; a third cooling water channel is circumferentially arranged around the motor housing, and a water inlet pipe connected to one end of the third cooling water channel and a water outlet pipe connected to the other end of the third cooling water channel are arranged on the motor housing.

4. The cooling structure for the motor reducer assembly of a new energy vehicle according to claim 3 is characterized in that: A motor front bearing and a motor front oil seal are arranged in sequence from left to right between the right end of the motor shaft and the inner wall of the shaft hole at the right end of the motor housing, and a reducer front oil seal and a reducer front bearing are arranged in sequence from left to right between the left end of the reducer input shaft and the inner wall of the shaft hole of the reducer front housing.

5. The cooling structure for the motor reducer assembly of a new energy vehicle according to claim 3, characterized in that: The water inlet interface pipe is connected to a first water inlet pipeline, and a first switch valve is arranged on the first water inlet pipeline.

6. The cooling structure for the motor reducer assembly of a new energy vehicle according to claim 3, characterized in that: The water inlet pipe is provided with a second water inlet pipeline, and the second water inlet pipeline is provided with a second switch valve.

7. The cooling structure for the motor reducer assembly of a new energy vehicle according to claim 6, characterized in that: A connecting pipeline is provided between the water outlet interface pipe and the water inlet pipe, and a third switch valve is provided on the connecting pipeline.

8. The cooling structure for the motor reducer assembly of a new energy vehicle according to claim 7, characterized in that: The water outlet interface pipe is connected to a water outlet pipeline, and a fourth switch valve is arranged on the water outlet pipeline.

9. The cooling structure for the motor reducer assembly of a new energy vehicle according to claim 1, characterized in that: A motor rear oil seal and a motor rear bearing are arranged in sequence from left to right between the left end of the motor shaft and the inner wall of the shaft hole of the motor rear end cover.

10. The cooling structure for the motor reducer assembly of a new energy vehicle according to any one of claims 1 to 9, characterized in that: A reducer rear bearing and a reducer rear oil seal are arranged in sequence from left to right between the right end of the reducer input shaft and the inner wall of the shaft hole of the reducer rear housing.

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