CN115899249A

CN115899249A - Electric drive assembly system reaches vehicle including it

Info

Publication number: CN115899249A
Application number: CN202111159460.5A
Authority: CN
Inventors: 赵振宇; 祝仕平; 刘婷婷; 王文辉; 马慧龙; 陈汝鹏; 邓晓雪; 胡浩强
Original assignee: Valeo Siemens eAutomotive Germany GmbH
Current assignee: Valeo eAutomotive Germany GmbH
Priority date: 2021-09-30
Filing date: 2021-09-30
Publication date: 2023-04-04

Abstract

The present invention relates to an electric drive assembly system comprising: a housing; a gearbox including an input shaft extending along a central axis and rotatably supported in the housing by a first bearing and a second bearing; wherein the electric drive assembly system further comprises a parking lock system comprising a parking ratchet fixed on the input shaft so as to be rotatable therewith; and wherein a first stop and a second stop are provided at a first side and a second side of the first bearing, respectively, in a direction of the central axis such that the first bearing is axially positioned on the input shaft, the parking ratchet being provided between the first bearing and the second bearing and abutting against the second side of the first bearing.

Description

Electric drive assembly system reaches vehicle including it

Technical Field

The present invention relates to the field of electric vehicles, and more particularly to an electric drive assembly system and a vehicle including the same.

Background

Vehicles typically include a parking device for assisting parking. The most common parking devices in the prior art often use wheel end braking. In recent years, electric vehicles have become more and more popular with increasing demands for energy and environmental protection. An electric drive system is typically used in an electric vehicle. The electric drive system may be a highly integrated system, which typically integrates a motor, an inverter, and a gearbox, for example. In some cases, it is also desirable to incorporate parking devices also into electric drive systems to provide customers with a highly integrated overall solution. However, the incorporation of the parking device into the electric drive system may cause an additional load, and in order to bear the additional load, the original structure of the electric drive system is usually redesigned and largely changed, and the labor and the manufacturing cost are significantly increased.

Disclosure of Invention

The object of the present invention is to solve the above problems by providing an electric drive assembly system that can bear the additional load of incorporating a parking lock system into a gear box using an original structure without redesign, thereby saving labor and manufacturing costs.

The electric drive assembly system according to the invention comprises: a housing; a gearbox including an input shaft extending along a central axis and rotatably supported in the housing by a first bearing and a second bearing; wherein the electric drive assembly system further comprises a parking lock system comprising a parking ratchet fixed on the input shaft so as to be rotatable therewith, and wherein first and second stops are provided at first and second sides of the first bearing, respectively, in the direction of the central axis so that the first bearing is axially positioned on the input shaft, the parking ratchet being provided between the first and second bearings and abutting against the second side of the first bearing.

Placing the parking ratchet wheel on the input shaft of the gearbox and rotating with it creates an additional load on the input shaft of the gearbox. On the one hand, this is because when the vehicle is parked, the load at the wheel end of the vehicle is transmitted under gravity back to the parking ratchet wheel through a series of transmission elements and finally to the bearings through the input shaft. Such loads can be particularly pronounced when the vehicle is parked on a hill. On the other hand, the parking ratchet wheel also needs to be fixed on the input shaft along the axial direction, and in order to reduce the noise of the electric drive assembly system, a pinion on the input shaft adopts a bevel gear structure, which can cause the axial load generated by the parking working condition to be far larger than the axial load under the conventional working condition.

In the present invention, the first bearing is positioned by the first stopper and the second stopper in the direction of the central axis so that the first bearing is fixed in both directions along the central axis, and the axial force applied to the first bearing is thus borne by the stopper structures on both sides thereof, whereby the additional load due to the introduction of the parking ratchet can be borne by only the one bearing (i.e., the first bearing).

In one embodiment, the first stop is a snap ring disposed on the input shaft.

In one embodiment, the second stop is a snap ring disposed on an inner wall of the housing and abutting against an outer race of the first bearing.

Thus, the inner ring of the first bearing is axially positioned by the first stopper and the parking ratchet wheel, the outer ring is axially positioned by the second stopper, and the inner ring and the outer ring of the first bearing are both fixed and supported on both sides in the axial direction, whereby a large load in the axial direction can be borne without the second bearing an axial load. In addition, the snap ring is simple in structure, easy to obtain, and simple to machine with snap ring matched structures (such as an annular groove arranged on the input shaft and a groove arranged on the inner wall of the shell), structural strength cannot be obviously weakened, and manufacturing cost cannot be obviously increased.

In one embodiment, the radially inner face of the parking ratchet wheel includes a first axial section for rotationally fixing to the input shaft and a second axial section for axial positioning relative to the input shaft.

In one embodiment, the first axial section is provided with splines for engagement with mating splines on the input shaft.

In one embodiment, the second axial section and the outer face of the input shaft are fixed relative to each other axially by an interference fit. Thereby, the axial positioning of the parking ratchet on the input shaft of the gearbox is further secured.

In one embodiment, a first axial end of the parking ratchet wheel axially abuts a second side of the first bearing and a second axial end of the parking ratchet wheel axially abuts a pinion on the input shaft.

In one embodiment, a first side of the second bearing abuts a pinion on the input shaft and a second side of the second bearing abuts a shoulder provided on the housing.

In one embodiment, the first bearing and the second bearing are deep groove ball bearings of the same size.

The invention also relates to a vehicle comprising the electric drive assembly system.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is apparent that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts. The following drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention.

FIG. 1 illustrates a partial cross-sectional view of an electric drive assembly system according to an embodiment of the present invention; and

FIG. 2 illustrates another partial cross-sectional view of an electric drive assembly system according to an embodiment of the present invention, showing only a portion of the gear box and the parking ratchet for clarity.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present invention without any creative effort also belong to the protection scope of the present invention.

In the present invention, the axial direction means a direction along the central axis X of the input shaft of the gear box, and the radial direction means a direction perpendicular to the central axis X.

Fig. 1 shows a partial section through an electric drive assembly system 1 according to the invention, taken in a section along a central axis X of an input shaft containing a gearbox and mainly showing the part of the electric drive assembly system 1 comprising the gearbox. The electric drive assembly system 1 may be installed in a motor vehicle.

As shown in fig. 1, an electric drive assembly system 1 according to the present invention may include a gearbox 20. The electric drive assembly system 1 may further comprise a permanent magnet synchronous motor and an inverter for controlling the motor, constituting a highly integrated electric drive assembly system.

The electric drive assembly system 1 may include a housing 10. The housing 10 may house therein, for example, a permanent magnet synchronous motor, an inverter, a gear box, and related elements. Illustratively, the gearbox may include a speed reducer. The housing 10 may include a main body forming a receiving chamber and an end cap closing the receiving chamber.

As shown in fig. 1 and 2, the gearbox 20 may include an input shaft 210, the input shaft 210 extending along a central axis X thereof and rotatably supported in the housing 10 by a first bearing 220 and a second bearing 230. Specifically, the input shaft 210 has a first end 215 and a second end 216 opposite the first end in the direction of the central axis X. In the example shown in fig. 1, the second end 216 of the input shaft 210 is closer to the housing 10 than the first end 215, such as closer to an end cap of the housing 10, and the first end 215 is located in a receiving chamber defined by a body of the housing 10. The first end 215 of the input shaft 210 is supported on the housing 10 via a first bearing 220 and the second end 216 is supported on the housing 10 via a second bearing 230, the housing 10 being correspondingly provided on its inner wall with receptacles for receiving the first bearing 220 and the second bearing 230.

The input shaft 210 has a tip portion 217 extending from its first end 215 in an axial direction away from the second end 216, the tip portion 217 being engageable for rotation with a motor shaft (not shown) of a permanent magnet synchronous motor. To this end, the outer peripheral wall of the end portion 217 may have external splines extending parallel to the central axis X and distributed around the central axis X, and the inner peripheral wall of the motor shaft may have internal splines fitted with the external splines.

The electric drive assembly system 1 according to the invention further comprises a parking lock system 30. The park lock system 30 is a park assist system that includes a parking ratchet and pawl. When parking, the pawl is inserted into the gear ring of the parking ratchet wheel to be meshed with the gear ring, so that the parking ratchet wheel cannot rotate, a series of transmission elements cannot rotate, wheels cannot rotate finally, and the parking purpose is achieved.

As described above and shown in fig. 1 and 2, the parking lock system 30 includes the parking ratchet wheel 310, and in the technical solution according to the present invention, the parking ratchet wheel 310 is fixed on the input shaft 210 of the gear housing 20 to be rotatable together with the input shaft 210. Placing the parking ratchet 310 on and rotating with the input shaft 210 of the gearbox 20 places additional load on the input shaft 210 of the gearbox 20. This is because, on the one hand, when the vehicle is parked, the load at the wheel end of the vehicle is transmitted back to the parking ratchet wheel by the action of gravity through the series of transmission elements and finally to the bearings through the input shaft 210. Such loads can be particularly pronounced when the vehicle is parked on a hill. On the other hand, the parking ratchet wheel needs to be fixed on the input shaft along the axial direction, and in order to reduce the noise of the electric drive assembly system, a pinion on the input shaft adopts a bevel gear structure, so that the axial load generated by the parking working condition is far greater than that under the conventional working condition. Accordingly, a new arrangement is needed to place the parking ratchet on the input shaft 210 of the gearbox 20 and to withstand the additional load it carries.

To describe the solution according to the present invention more clearly, the sides of the first and

second bearings

220 and 230 facing the inside of the housing 10 are referred to as a first side (i.e., the right side of the orientation shown in fig. 1 and 2), and the sides thereof facing the outside of the housing 10 are referred to as a second side (i.e., the left side of the orientation shown in fig. 1 and 2).

As shown, first and

second stops

240, 250 are provided on first and

second sides

221, 222 of the first bearing 220, respectively, in the direction of the central axis X, such that the first bearing 220 is axially positioned on the input shaft 210. Specifically, the first stopper 240 may be a snap ring disposed on the input shaft 210, which is inserted in a circumferential groove on an outer wall of the input shaft 210 and abuts against an inner race of the first bearing 220 at a first side of the first bearing 220. The second stopper 250 may be a snap ring disposed on an inner wall of the housing 10, which abuts against an outer race of the first bearing 220 at the second side 222 of the first bearing 220. Furthermore, the outer ring of the first bearing 220 is positioned against the inner wall of the housing 10 at the first side 221.

Further, the parking ratchet 310 is disposed between the first bearing 220 and the second bearing 230, i.e., between the second side 222 of the first bearing 220 and the first side 231 of the second bearing 230, and abuts against the second side 222 of the first bearing 220.

Thus, in the direction of the central axis X, the inner race of the first bearing 220 is positioned by the first stopper 240 and the parking ratchet 310, and the outer race is positioned by the second stopper 250 and the housing 10, so that the first bearing 220 is fixed in both directions along the central axis X, whereby the additional load due to the introduction of the parking ratchet 310 can be carried by only one bearing (the first bearing 220).

Preferably, the first bearing 220 and the second bearing 230 may be deep groove ball bearings of the same size. The deep groove ball bearing generally does not bear axial force or can bear smaller axial force only, and is fixed on one side along the axial direction, so that when one bearing supporting the same shaft needs to bear larger axial load in the prior art, two bearings are selected to have larger size difference to adapt to different requirements, or special design is needed, great labor burden is brought, and the development and production period is prolonged.

However, in the present invention, the two bearings supporting the input shaft may have the same size, the same model, and the same manufacturing process without spending additional manpower and time for selection and special design, thereby saving manufacturing costs and manpower burdens. In addition, in the invention, under the condition that the gear box uses the deep groove ball bearing, one of the bearings can be positioned in a bidirectional stopping way along the direction of the central axis X under the condition that the original bearing and the arrangement position thereof are not changed, so that the bearing can bear the extra axial load brought by the parking ratchet wheel, only slight change needs to be carried out on the original structure (for example, a groove capable of placing a clamping ring is processed), and therefore, the labor and the manufacturing cost are saved.

The manner in which the parking ratchet 310 is fixed to the input shaft 210 is described in detail below with reference to fig. 1 and 2. As shown in fig. 1 and 2, the parking ratchet 310 has a central through hole on the central axis X, and is fitted over the input shaft 210 of the gear housing 20 through the central through hole. The radially inner face of the parking ratchet 310, i.e. the inner wall defining the central through hole, may comprise two sections in the direction of the central axis X: a first axial section 311 for rotationally fixing to the input shaft 210; and a second axial section 312 for axial positioning relative to the input shaft 210.

The first axial section 311 may be provided with splines and the outer wall of the input shaft 210 is provided with mating splines to engage therewith such that the parking ratchet 310 rotates with the input shaft 210.

The second axial section 312 may be fixed relative to the axial one another by way of an interference fit with the outer face of the input shaft 210.

As previously described, the parking ratchet 310 is axially positioned on the input shaft 210 axially against the second side 222 of the first bearing 220. More specifically, the parking ratchet 310 has a first axial end 315 facing the first bearing 220 and a second axial end 316 axially opposite the first axial end 315, the first axial end 315 axially abutting the second side 222 of the first bearing 220 and the second axial end 316 axially abutting the pinion gear 211 on the input shaft 210. The pinion gear 211 may be a pinion gear integrally formed on the input shaft 210. Accordingly, the axial fixation of the parking ratchet 310 to the input shaft 210 of the gear housing 20 utilizes the first bearing 220 existing in the gear housing 20 when the parking ratchet 310 is not provided and the pinion 211 on the input shaft 210, and there is no need to greatly change the original structure.

The axial positioning of the second bearing 230 supporting the second end 216 of the input shaft 210 is also achieved by the pinion gear 211. Specifically, as shown in fig. 1, a first side 231 of the second bearing 230 abuts against the pinion gear 211 on the input shaft 210, and a second side 232 abuts against the shoulder 110 provided on the housing 10.

According to another aspect of the invention, a motor vehicle is proposed, comprising an electric drive assembly system as described above.

The motor vehicle may be a Plug-in Hybrid Electric vehicle (Plug-in Hybrid Electric vehicle), or it may be a Battery Electric vehicle (Battery Electric vehicle) or other type of motor vehicle. Based on the above, the motor vehicle can realize the functions of the motor component and the motor as described above, and has the advantages as described above.

Certain features, structures, or characteristics may be combined as suitable in one or more embodiments of the application.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

The foregoing is illustrative of the present invention and is not to be construed as limiting thereof. Although a few exemplary embodiments of this invention have been described, those skilled in the art will readily appreciate that many modifications are possible in the exemplary embodiments without materially departing from the novel teachings and advantages of this invention. Accordingly, all such modifications are intended to be included within the scope of this invention as defined in the claims. It is to be understood that the foregoing is illustrative of the present invention and that this invention is not to be considered limited to the specific embodiments disclosed, and that modifications to the disclosed embodiments, as well as other embodiments, are intended to be included within the scope of the invention.

Claims

1. An electric drive assembly system (1), characterized in that the electric drive assembly system (1) comprises:

a housing (10);

a gearbox (20) comprising an input shaft (210) extending along a central axis (X) and rotatably supported in said housing (10) by a first bearing (220) and a second bearing (230);

wherein the electric drive assembly system (1) further comprises a parking lock system (30) comprising a parking ratchet wheel (310), the parking ratchet wheel (310) being fixed on the input shaft (210) to be rotatable together with the input shaft (210),

and wherein a first stop (240) and a second stop (250) are provided at a first side (221) and a second side (222) of the first bearing (220) in the direction of the centre axis (X) respectively such that the first bearing (220) is axially positioned on the input shaft (210), the parking ratchet (310) being provided between the first bearing (220) and the second bearing (230) and abutting against the second side (222) of the first bearing (220).

2. The electric drive assembly system (1) of claim 1, characterized in that the first stop (240) is a snap ring disposed on the input shaft (210).

3. The electric drive assembly system (1) of claim 1, characterized in that the second stop (250) is a snap ring disposed on an inner wall of the housing (10) and abutting against an outer ring of the first bearing (220).

4. The electric drive assembly system (1) according to any one of claims 1 to 3, characterized in that a radially inner face of the parking ratchet (310) comprises a first axial section (311) for rotationally fixing to the input shaft (210) and a second axial section (312) for axial positioning with respect to the input shaft (210).

5. The electric drive assembly system (1) according to claim 4, characterized in that the first axial section (311) is provided with splines for engagement with mating splines on the input shaft (210).

6. The electric drive assembly system (1) of claim 4, characterized in that the second axial section (312) and the outer face of the input shaft (210) are fixed relative to each other axially by interference fit.

7. The electric drive assembly system (1) of any of claims 1 to 3, characterized in that a first axial end (315) of the parking ratchet (310) axially abuts against a second side (222) of the first bearing (220), and a second axial end (316) of the parking ratchet axially abuts against a pinion (211) on the input shaft (210).

8. The electric drive assembly system (1) according to any one of claims 1 to 3, characterized in that a first side (231) of the second bearing (230) abuts against a pinion (211) on the input shaft (210) and a second side (232) of the second bearing (230) abuts against a shoulder (110) provided on the housing (10).

9. The electric drive assembly system (1) according to any one of claims 1 to 3, characterized in that the first bearing (220) and the second bearing (230) are deep groove ball bearings of the same size.

10. A vehicle comprising the electric drive assembly system of any one of claims 1-9.