CN211995122U - Electric drive system - Google Patents

Abstract

An electric drive system is disclosed. The electric drive system comprises an electric machine and a gearbox, the torque of a rotor of the electric machine being transmitted to a gearbox input shaft of the gearbox via a rotor shaft fixedly connected to the rotor, wherein the rotor shaft and the gearbox input shaft are each configured hollow, the rotor shaft and the gearbox input shaft are nested within one another, a housing splitter is provided at the end of the gearbox input shaft for conveying oil to the hollow of the gearbox input shaft and to the hollow of the rotor shaft. According to the utility model discloses an electric drive system can have improved cooling performance.

Description

Electric drive system

Technical Field

The utility model relates to an automotive filed particularly, relates to an electric drive system.

Background

The electric drive system is a power source of the electric automobile and is directly related to the performance of the automobile. The electric drive system includes, for example, a gear box and a motor. The current electric drive system adopts a water cooling mode to cool the motor; with the continuous increase of the rotating speed and the power of the motor, the traditional water cooling mode cannot meet the heat dissipation requirement of the motor; when the heat can not be dissipated quickly, the temperature of the motor can be increased continuously, the motor works in a derating mode, and even faults are caused. For the water-cooled motor, because the cavity where the motor rotates in a fixed mode needs to be kept dry, strict sealing is needed between the gear box and the motor so as to prevent oil of the gear box from entering the cavity of the motor; the bearings of the motor cannot be lubricated by oil, and in order to ensure the performance and the service life, the bearings at the two ends of the motor must use grease-lubricated high-speed bearings, which are expensive and not beneficial to cost control. The water jacket of the current motor is mainly used for radiating the stator, and the rotor shaft generally adopts a solid structure, so that the temperature of the rotor is difficult to control; the rotor temperature is too high, which can lead to the performance reduction and even demagnetization failure of the permanent magnet in the rotor on one hand; on the other hand, the life of parts such as bearings and oil seals that come into contact with the rotor shaft is adversely affected.

Therefore, it is necessary to sufficiently study the existing problems or disadvantages including the above-mentioned cases so as to improve them.

SUMMERY OF THE UTILITY MODEL

The utility model provides an electric drive system, it can have improved cooling performance.

According to the utility model discloses an aspect proposes electric drive system, including motor and gear box, the torque of the rotor of motor through with rotor fixed connection's rotor shaft transmits the gear box input shaft of gear box, wherein, the rotor shaft and the gear box input shaft is hollow ground structure respectively, the rotor shaft with the gear box input shaft overlaps each other and puts the tip of gear box input shaft is equipped with the casing shunt for carry oil the hollow part of gear box input shaft, and carry oil the hollow part of rotor shaft.

According to the utility model discloses an aspect provides an electric drive system, the rotor shaft sleeve is put in the gear box input shaft be equipped with the external splines on the rotor shaft be equipped with the internal splines on the gear box input shaft, through the external splines with the spline fit that the internal splines formed is followed the rotor shaft transmits to the gear box input shaft.

According to the utility model discloses an aspect provides an electric drive system, the rotor shaft includes the rotor shaft connecting axle, rotor shaft connecting axle sleeve is put in the gear box input shaft.

According to the utility model discloses an aspect provides an electric drive system, electric drive system still includes input shaft first bearing and input shaft second bearing, the input shaft first bearing with the input shaft second bearing supports at both ends respectively the gear box input shaft, and the input shaft second bearing still supports at one end the rotor shaft.

According to an aspect of the present invention, there is provided an electric drive system further comprising a rotor bearing supporting the rotor shaft at the other end opposite to the input shaft second bearing.

According to the utility model discloses an aspect provides electric drive system is equipped with the hole at the end of rotor shaft for oil can pass through the hole flows through rotor bearing.

According to the utility model discloses an aspect provides an electric drive system, electric drive system still includes gear box jackshaft and gear box output shaft, sets up jackshaft gear on the gear box jackshaft is in with the setting input shaft gear engagement on the gear box input shaft and with set up output shaft gear engagement on the gear box output shaft.

According to the utility model discloses an aspect provides an electric drive system, the gear box jackshaft constructs hollowly the tip of gear box input shaft is equipped with the jackshaft and leads oil pipe for carry oil the hollow part of gear box jackshaft.

According to the utility model discloses an aspect provides an electric drive system, electric drive system still includes jackshaft first bearing and jackshaft second bearing, the jackshaft first bearing with the jackshaft second bearing supports at both ends respectively the gear box jackshaft, oil can via the hollow part of jackshaft flows through the jackshaft first bearing with the jackshaft second bearing.

According to an aspect of the present invention, there is provided an electric drive system, comprising:

a gearbox housing and a motor housing, which are constructed as one piece and form a main housing, in which an oil delivery system is provided, which can deliver oil for cooling the gearbox and the motor;

a gearbox housing lower splitter disposed in the gearbox housing;

a gearbox housing upper splitter disposed in the gearbox housing in communication with the gearbox housing lower splitter for conveying oil to cool the gearbox;

a main housing motor diverter disposed in said main housing in communication with said gear housing lower diverter for delivering oil to cool the motor; and

a gearbox cavity disposed between the gearbox housing and the motor housing;

wherein oil in the oil path is branched after the gearbox housing lower splitter to the gearbox housing upper splitter or the main housing motor splitter, then pooled in the gearbox cavity, and finally returned to the gearbox housing lower splitter.

The beneficial effects of the utility model include: the hollow rotor shaft and the gearbox input shaft are arranged in a nested manner, so that oil can be supplied to the rotor shaft via the gearbox input shaft, and the gearbox input shaft and the rotor shaft can be cooled efficiently.

Drawings

The disclosure of the present invention is explained with reference to the drawings. It is to be understood that the drawings are designed solely for the purposes of illustration and not as a definition of the limits of the invention. In the drawings, like reference numerals are used to refer to like parts unless otherwise specified. Wherein:

fig. 1 schematically shows, in a view, an electric drive system according to an embodiment of the present invention;

FIG. 2 schematically illustrates the electric drive system of FIG. 1 from another perspective;

FIG. 3 schematically illustrates the electric drive system of FIG. 1 in an exploded view;

FIG. 4 schematically illustrates, in an enlarged view, a portion of the electric drive system of FIG. 1;

fig. 5 schematically shows the electric drive system of fig. 1 in a sectional view.

Detailed Description

It is easily understood that, according to the technical solution of the present invention, a plurality of alternative structural modes and implementation modes can be proposed by those skilled in the art without changing the spirit of the present invention. Therefore, the following detailed description and the accompanying drawings are merely illustrative of the technical solutions of the present invention, and should not be considered as limiting or restricting the technical solutions of the present invention in their entirety or in any other way.

The terms of orientation of up, down, left, right, front, back, top, bottom, and the like referred to or may be referred to in this specification are defined relative to the configuration shown in the drawings, and are relative terms, and thus may be changed correspondingly according to the position and the use state of the device. Therefore, these and other directional terms should not be construed as limiting terms.

According to an embodiment of the present invention, shown in conjunction with fig. 1 to 5, it can be seen that: the electric drive system comprises a gear box shell assembly 1, an integrated shell assembly 2, a motor end cover assembly 3, an input shaft assembly 4, an intermediate shaft assembly 5, an output shaft assembly 6, a rotor assembly 7, a stator assembly 8, a maintenance cover plate 9, an electronic oil pump 10, a gear oil filter 11 and a heat exchanger 12. The gearbox shell assembly comprises a gearbox shell 101 and a shell flow divider 102, and the input shaft assembly 4 comprises an input shaft first bearing 401, an input shaft second bearing 402 and a gearbox input shaft 403; the intermediate shaft assembly comprises an intermediate shaft first bearing 501, an intermediate shaft second bearing 502, an intermediate shaft oil guide pipe 503 and a gearbox intermediate shaft 504; the output shaft assembly 6 comprises an output shaft first bearing 601, an output shaft second bearing 602, a differential 603 and an output shaft gear 604; rotor assembly 7 includes rotor 701, rotor shaft oil conduit 702, rotor shaft coupling shaft 703, rotor shaft splitter 704, rotor shaft 705, rotor bearing 706.

In particular, the electric drive system comprises an electric machine and a gearbox, the torque of the rotor of the electric machine being transmitted to the gearbox input shaft of the gearbox via a rotor shaft fixedly connected to the rotor, wherein the rotor shaft and the gearbox input shaft are each configured hollow, the rotor shaft and the gearbox input shaft are nested within one another, a housing splitter is provided at the end of the gearbox input shaft for conveying oil to the hollow part of the gearbox input shaft (in the center of the gearbox input shaft) and to the hollow part of the rotor shaft (in the center of the rotor shaft). In the electric drive system, the rotor shaft and the gearbox input shaft which are hollow and are nested with each other enable oil to be conveyed to the rotor shaft through the gearbox input shaft, so that the gearbox input shaft and the rotor shaft can be cooled efficiently; particularly, the risk of demagnetization of the permanent magnet in the motor rotor can be effectively avoided for the rotor shaft, and the service life of parts such as an oil seal, a bearing and the like which are in contact with the motor shaft is prolonged.

The term "oil" as used herein is understood to mean cooling oil or lubricating oil which, according to its physical properties, can act both for cooling and lubrication purposes when flowing through the component.

The rotor shaft is arranged in the gear box input shaft, an external spline is arranged on the rotor shaft, an internal spline is arranged on the gear box input shaft, and torque is transmitted to the gear box input shaft from the rotor shaft through the spline fit formed by the external spline and the internal spline. Specifically, the rotor shaft comprises a right body and a left rotor shaft connecting shaft, and the rotor shaft connecting shaft is sleeved in the gearbox input shaft. The left rotor shaft connecting shaft is fixed with the right body through welding. A rotor shaft splitter may also be provided in the hollow body of the rotor shaft for distributing the oil delivered through the gearbox input shaft evenly to the inner wall of the rotor shaft, so that the rotor shaft can be cooled more efficiently.

The electric drive system further includes an input shaft first bearing and an input shaft second bearing, the input shaft first bearing and the input shaft second bearing supporting the gearbox input shaft at both ends, respectively, and the input shaft second bearing also supporting the rotor shaft at one end. Specifically, the rotor shaft is aligned with the input shaft of the gear box through a section of optical axis (specifically, a part corresponding to a second bearing of the input shaft on a connecting shaft of the rotor shaft); meanwhile, the section of optical axis also plays a supporting role, namely the second bearing of the input shaft supports the rotor shaft through the input shaft of the gear box; the design realizes that the gear box and the motor share the supporting bearing, reduces the using amount of the high-speed bearing and the cost, effectively reduces the over-constraint risk possibly existing in the rotor shaft-gear box input shaft, does not need high spline jumping control to ensure good centering assembly, and avoids the NVH problem caused by periodic stress during working.

The electric drive system further includes a rotor bearing supporting the rotor shaft at another end opposite the input shaft second bearing. Further, a hole is formed in the gearbox housing above the splitter so that oil can be directly injected through the hole to the input shaft first bearing. Holes are provided at the end of the rotor shaft so that oil can flow through the rotor bearing. In this way, the first input shaft bearing and the rotor bearing can be effectively lubricated and cooled.

The electric drive system further includes a gearbox intermediate shaft and a gearbox output shaft, an intermediate shaft gear provided on the gearbox intermediate shaft meshing with an input shaft gear provided on the gearbox input shaft and meshing with an output shaft gear provided on the gearbox output shaft, so that a torque of the rotor shaft is finally output from the gearbox output shaft through a two-stage reduction mechanism formed by the gearbox input shaft, the gearbox intermediate shaft and the gearbox output shaft.

Further, the gearbox intermediate shaft is configured to be hollow, and an intermediate shaft oil guide pipe is provided at an end portion of the gearbox input shaft for conveying oil to the hollow portion of the gearbox intermediate shaft, thereby efficiently cooling the gearbox intermediate shaft. Still further, the electric drive system further includes an intermediate shaft first bearing and an intermediate shaft second bearing that support the gearbox intermediate shaft at both ends, respectively, through which oil can flow via a hollow portion of the intermediate shaft. In this way, the first intermediate shaft bearing and the second intermediate shaft bearing can be lubricated and cooled effectively.

According to an embodiment of the present invention, the electric drive system comprises a gearbox housing and a motor housing, the gearbox housing and the motor housing being constructed as one and forming a main housing in which an oil delivery system is provided which is capable of delivering oil for cooling the gearbox and the motor. In the electric drive system, by constructing the gear box housing and the motor housing as one body, the system rigidity of the electric drive system is improved and the weight and the volume are reduced; and the gear box and the motor can be efficiently cooled by oil through the arranged oil conveying system. In addition, the electric drive system further includes an inverter housing configured as one body with the main housing.

The oil delivery system is configured such that oil used to cool the gearbox is in communication with oil used to cool the electric machine. In this way, for example, the gear box lubricating oil necessary for the gear box can be supplied to components such as the motor and the inverter, which generate heat in large quantities during operation, and the function of efficient cooling can be achieved.

The electric drive system (or oil delivery system) further comprises: a gearbox housing lower splitter disposed in the gearbox housing; a gearbox housing upper splitter disposed in the gearbox housing in communication with the gearbox housing lower splitter for conveying oil to cool the gearbox; a main housing motor splitter disposed in the main housing in communication with the gearbox housing lower splitter for delivering oil to cool a motor (e.g., a stator of the motor); and a gearbox cavity disposed between the gearbox housing and the motor housing. Wherein oil in the oil path is branched after the gearbox housing lower splitter to the gearbox housing upper splitter or the main housing motor splitter, then pooled in the gearbox cavity, and finally returned to the gearbox housing lower splitter.

The main shell is provided with an oil passage for conveying oil from the lower gearbox shell splitter to the upper gearbox shell splitter or conveying oil from the lower gearbox shell splitter to the main shell motor splitter.

The electric drive system (or the oil transportation system) also comprises an electronic oil pump, an oil filter and a heat exchanger. Oil flows through the electronic oil pump, oil filter and heat exchanger in an oil circuit after the gearbox cavity and returns to the gearbox housing lower flow divider.

The electric drive system (or oil delivery system) further comprises: the motor oil guide groove is arranged on the motor shell and is communicated with the main shell motor shunt; and the motor oil distribution ring is arranged in the motor shell and is communicated with the motor oil guide groove. Wherein oil is delivered to the motor oil distribution ring through the motor oil guide groove to cool the stator in the motor housing.

Specifically, the motor oil guiding groove comprises a motor outer side oil guiding groove and a motor inner side oil guiding groove, the motor oil distribution ring comprises a motor front end oil distribution ring and a motor rear end oil distribution ring, oil can be conveyed to the motor front end oil distribution ring and the motor rear end oil distribution ring through the motor outer side oil guiding groove, and the oil can also be conveyed to the motor front end oil distribution ring and the motor rear end oil distribution ring through the motor inner side oil guiding groove.

For example, the oil distribution ring of the motor forms a receiving space for cooling oil by cooperation with the motor housing and/or the stator, and holes are provided on the oil distribution ring of the motor so that the cooling oil received in the receiving space can flow through the stator through the holes, thereby cooling the stator in a simple and effective manner.

The electric drive system (or oil delivery system) further comprises: a hollow gearbox input shaft in communication with the gearbox housing upper splitter; a hollow motor rotor shaft in communication with the gearbox input shaft; and a rotor bearing for supporting the motor rotor shaft. For example, holes may be provided in the motor rotor shaft at the locations where the rotor bearings are carried, so that oil can flow from the motor rotor shaft through the rotor bearings via the holes. The oil flows through the gear box input shaft, the motor rotor shaft and the rotor bearing in sequence under the driving of the oil pump, so that the gear box input shaft, the motor rotor shaft and the rotor bearing are cooled and the rotor bearing is lubricated.

The electric drive system (or oil delivery system) further includes an input shaft first bearing for supporting the gearbox input shaft through which oil flows via a splitter on the gearbox housing. For example, holes may be provided in the gearbox housing at a location in the splitter corresponding to the input shaft first bearing, such that oil can flow from the gearbox housing through the input shaft first bearing via the holes, thereby cooling and lubricating the input shaft first bearing.

The electric drive system (or oil delivery system) further includes a gearbox housing spray splitter in communication with the splitter on the gearbox housing for spraying oil onto the gearbox input shaft engaging flanks and the input shaft second bearing for supporting the gearbox input shaft for cooling and lubricating the gearbox input shaft engaging flanks and the input shaft second bearing. The jet splitter can be made of plastic, for example.

The electric drive system (or oil delivery system) further comprises: a hollow gearbox intermediate shaft in communication with the gearbox housing upper splitter; and an intermediate shaft first bearing and an intermediate shaft second bearing for supporting the intermediate shaft. For example, holes may be provided in the gearbox intermediate shaft at locations distributed over the locations on which the intermediate shaft first bearing and the intermediate shaft second bearing are carried, such that oil can flow from the gearbox intermediate shaft through the intermediate shaft first bearing and the intermediate shaft second bearing via the holes. Wherein oil is delivered through the gearbox intermediate shaft to the intermediate shaft first bearing and the intermediate shaft second bearing to cool and lubricate the gearbox intermediate shaft, the intermediate shaft first bearing and the intermediate shaft second bearing.

Further, oil flowing through the motor front end oil distribution ring, the motor rear end oil distribution ring, and the rotor bearing flows back into the motor bottom sump, for example, due to gravity, and then flows back into the gearbox cavity from the motor bottom sump through a pipe.

In addition, the electric drive system (or oil delivery system) further comprises a main housing inverter shunt and an inverter oil passage, the main housing inverter shunt is communicated with the main housing motor shunt, and the inverter oil passage is communicated with the main housing inverter shunt, so that the inverter can be cooled by oil.

Technical effects that can be achieved by the electric drive system according to the present application include: the electric drive system adopts a full oil cooling structure, and active circulation cooling of the motor is realized by introducing the gearbox oil into a cavity of the motor; because gear box oil direct action is on the stator and the rotor that the motor generates heat, the indirect heat exchange mode of heat transfer to the coolant liquid through motor casing in the relative water cooled machine has higher heat exchange efficiency, is favorable to the promotion of motor continuous power. The oil cooling structure realizes oil passing through the cavity of the motor, the input shaft and the intermediate shaft of the gear box adopt hollow structures, and the oil of the gear box is led into three bearings on the axis of the motor and two bearings of the intermediate shaft through oil path design, so that the bearings are lubricated forcibly; the forced lubrication is more stable than the splash lubrication, and the performance requirement of the bearing can be effectively reduced; meanwhile, as the oil lubrication is realized for the bearing at the tail part of the motor, the requirement on the bearing can be further reduced, and the expensive high-speed grease lubrication bearing does not need to be selected, thereby being beneficial to controlling the cost. The electric drive system adopts an integrated shell, and the gear box and the motor are not connected through screws, so that the rigidity of the system is ensured, and the weight and the volume of the electric drive system are effectively reduced.

The technical scope of the present application is not limited to the contents in the above description, and those skilled in the art can make various changes and modifications to the above embodiments without departing from the technical spirit of the present application, and these changes and modifications should fall within the protective scope of the present application.

Claims (10)

1. An electric drive system, characterized in that it comprises an electric motor and a gearbox, the torque of the rotor of the electric motor being transmitted to the gearbox input shaft of the gearbox via a rotor shaft fixedly connected to the rotor, wherein the rotor shaft and the gearbox input shaft are each configured hollow, the rotor shaft and the gearbox input shaft are nested inside each other, a housing splitter is provided at the end of the gearbox input shaft for conveying oil to the hollow part of the gearbox input shaft and oil to the hollow part of the rotor shaft.

2. The electric drive system of claim 1 wherein said rotor bushing is disposed in said gearbox input shaft, external splines are provided on said rotor shaft, internal splines are provided on said gearbox input shaft, and torque is transmitted from said rotor shaft to said gearbox input shaft by a spline engagement of said external splines with said internal splines.

3. The electric drive system of claim 2 wherein said rotor shaft includes a rotor shaft coupling shaft, said rotor shaft coupling sleeve being received in said gearbox input shaft.

4. The electric drive system of claim 2 further comprising an input shaft first bearing and an input shaft second bearing, the input shaft first bearing and the input shaft second bearing supporting the gearbox input shaft at both ends, respectively, and the input shaft second bearing also supporting the rotor shaft at one end.

5. The electric drive system of claim 4, further comprising a rotor bearing supporting the rotor shaft at an opposite end from the input shaft second bearing.

6. An electric drive system according to claim 5, characterized in that holes are provided at the end of the rotor shaft, so that oil can flow through the rotor bearing through the holes.

7. The electric drive system of claim 1 further comprising a gearbox intermediate shaft and a gearbox output shaft, an intermediate shaft gear disposed on the gearbox intermediate shaft meshing with an input shaft gear disposed on the gearbox input shaft and meshing with an output shaft gear disposed on the gearbox output shaft.

8. An electric drive system according to claim 7, characterized in that the gearbox intermediate shaft is configured hollow, and an intermediate shaft oil conduit is provided at the end of the gearbox input shaft for conveying oil to the hollow part of the gearbox intermediate shaft.

9. The electric drive system of claim 8 further comprising an intermediate shaft first bearing and an intermediate shaft second bearing, the intermediate shaft first bearing and the intermediate shaft second bearing supporting the gearbox intermediate shaft at both ends, respectively, oil being able to flow through the intermediate shaft first bearing and the intermediate shaft second bearing via a hollow portion of the intermediate shaft.

10. The electric drive system of claim 1, comprising:

a gearbox housing and a motor housing, which are constructed as one piece and form a main housing, in which an oil delivery system is provided, which can deliver oil for cooling the gearbox and the motor;

a gearbox housing lower splitter disposed in the gearbox housing;

a gearbox housing upper splitter disposed in the gearbox housing in communication with the gearbox housing lower splitter for conveying oil to cool the gearbox;

a main housing motor diverter disposed in said main housing in communication with said gear housing lower diverter for delivering oil to cool the motor; and

a gearbox cavity disposed between the gearbox housing and the motor housing;

wherein oil in the oil path is branched after the gearbox housing lower splitter to the gearbox housing upper splitter or the main housing motor splitter, then pooled in the gearbox cavity, and finally returned to the gearbox housing lower splitter.

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