Description:FIELD OF INVENTION

The present invention relates to electric powertrain in battery-powered or hybrid vehicles. In particular, the present invention relates to an e-axle assembly for battery-powered vehicles. More particularly, the present invention relates to the gearbox of an e-axle assembly for battery-powered vehicles, in which bevel gears are used both for primary and final drive in the gearbox thereof.

BACKGROUND OF THE INVENTION

The conventional rear axle assembly includes a number of sub-assemblies, e.g. gearbox, normally having spur/helical gears, transmission and the like.

However, the e-axle comprises electric motor, power electronics and transmission combined in a compact unit for powering the axle of battery-electric vehicles.

The e-axle offers a compact and cost-efficient solution for battery-powered and/or hybrid vehicles by making them less complex and cost-effective due to a simpler configuration thereof.

In particular, in electric or hybrid Light/Small Commercial Vehicle (LCV/SCV) segment or pick-up vehicles, the torque available at the wheels is more important than the speed, which necessitates a higher gear-ratio therein.

The total torque to pull the electric vehicle cannot be achieved with a single gear-ratio, for example, by directly connecting the electric motor to the final drive gear (e.g. via spur or helical gears).
In gearbox having a single gear-ratio, the electric motor should have higher capacity torque with high voltage range and requires enhancing the battery capacity which in turn increases the cost of such electric LCV/SCVs.

This higher torque on the wheels of electric LCV/SCVs can only be achieved by an electric motor having optimum torque capacity by using an additional gear-ratio apart from the final drive gear-ratio.

Therefore, there is an existing need for developing an e-axle assembly for LCV/SCV segment of vehicles, which should not only produce a higher torque from the gearbox (e.g. overall gear-ratio of about 12-14) at the wheels thereof but should also be cost-efficient by optimum range of toque produced thereby.

OBJECTS OF THE INVENTION

Some of the objects of the present invention - satisfied by at least one embodiment of the present invention - are as follows:

An object of the present invention is to provide an e-axle assembly for electric or hybrid Light/Small Commercial Vehicles (LCV/SCV).

Another object of the present invention is to provide an e-axle assembly for electric or hybrid Light/Small Commercial Vehicles (LCV/SCV), which is low-cost.

Still another object of the present invention is to provide an e-axle assembly for electric or hybrid Light/Small Commercial Vehicles (LCV/SCV), which offers higher torque at wheels thereof.

Yet another object of the present invention is to provide an e-axle assembly for electric or hybrid Light/Small Commercial Vehicles (LCV/SCV), which overcomes the packaging constraints with the conventional electric powertrain.

These and other objects and advantages of the present invention will become more apparent from the following description, when read with the accompanying figures of drawing, which are however not intended to limit the scope of the present invention in any way.

DESCRIPTION OF THE INVENTION

In the compact e-axle assembly for electric powertrain of electric or hybrid Light/Small Commercial Vehicles (LCVs/SCVs) configured in accordance with the present invention, the packaging constraint is overcome by placing the electric motor in a transverse direction.

Here, the electric motor is disposed in a direction perpendicular to the axis of the counter-shaft, and the bevel gear arrangement is best-suited for transferring torque at 900 to the axis.

In addition, the reducer/gearbox for this new electric powertrain comprises bevel gears both at primary and final drive stages, instead of the conventional spur/helical gears discussed in the background section.

Thus, this e-axle assembly configuration provides the required higher torque at the wheels, in addition to the targeted cost-efficiencies.

SUMMARY OF INVENTION

In accordance with the present invention, there is provided an e-axle assembly for electric powertrain of an electric or hybrid Light/Small Commercial Vehicle (LCV/SCV), comprising:

• a primary stage carrying a pair of bevel gears engaged with an electric motor;

• a counter-shaft connecting said primary stage to a final stage;

• the final stage carrying a final bevel gear mounted on the counter-shaft; and

• the final stage connected to the output shaft via a transmission;

wherein the electric motor is disposed parallel to the output shaft for the transmission and configured to optimally transfer torque to the output shaft.

Typically, the primary stage comprises a first bevel gear mounted on an input shaft of the electric motor.

Typically, the primary stage comprises a second bevel gear engaged with the first bevel gear and mounted on the counter-shaft.

Typically, the counter-shaft is configured as a hypoid pinion or shaft.

Typically, the final stage is configured with a hypoid gear pair arrangement.

Typically, the final stage comprises a final bevel gear mounted on the counter-shaft and connected to the output shaft via a transmission.
Typically, the final stage comprises a final bevel gear mounted on the counter-shaft configured as a hypoid pinion.

Typically, the electric motor is disposed parallel to the output shaft for the transmission.

Typically, the electric motor optimally transfers torque at 900 to the axis of the output shaft.

Typically, the e-axle assembly comprises:

• a primary stage carrying a first bevel gear engaged with an electric motor, and a second bevel gear engaged with the first bevel gear and mounted on the counter-shaft;

• the counter-shaft configured as a hypoid pinion or shaft, and connecting the primary stage to the final stage;

• the final stage is configured with a hypoid gear pair arrangement having a final bevel gear mounted on the counter-shaft; and

• the final stage connected to the output shaft via the transmission;

wherein the electric motor is disposed parallel to the output shaft for the transmission and configured to optimally transfer torque at 900 to the axis of the output shaft.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

The present invention will be briefly described in the following with reference to the accompanying drawings.
Figure 1 shows a sectional view of the conventional gearbox of an electric powertrain for Light/Small Commercial Vehicle (LCV/SCV) segment of vehicles.

Figure 2 shows an e-axle assembly configured with bevel gears at both primary and final drive stage in accordance with the present invention.

Figure 3 shows an enlarged view of the middle portion of the axle assembly of Figure 2 along with the electric motor mounted therewith.

Figure 4 shows an e-axle assembly configured with a bevel gear pair at the primary and final drive stage in accordance with the present invention.

DETAILED DESCRIPTION OF THE ACCOMPANYING DRAWINGS

In the following, e-axle assembly configured in accordance with the present invention will be described in more details with reference to the accompanying drawings without limiting the scope and ambit of the present invention.

Figure 1 shows a sectional view of the conventional gearbox of an electric powertrain for Light/Small Commercial Vehicle (LCV/SCV) segment of vehicles. It shows an input shaft 10 connected to the electric motor EM (not shown) transferring power P via primary spur/helical gear arrangement 50 at a primary gear-ratio to a final spur/helical gear arrangement 60 at a final gear-ratio to the transmission T thereof. In the conventional Electric Gear Box, the prime mover is an electric motor with the input shaft thereof connected thru a spline for transferring the motor torque therethrough. The primary drive gear is a spur or helical gear integrated with the input shaft. The motor torque is transferred from the primary drive gear to the primary driven gear assembled on the counter-shaft. The primary gear pair 50 combines the drive and driven gears. The primary driven gear is assembled on the counter-shaft with an interference fit for transferring the torque. The final drive 70, a pinion (spur or helical pinion) is integrated with the counter-shaft. The torque transfer takes place from the final drive pinion to the final driven gear.

Figure 2 shows an e-axle assembly for electric powertrain of electric or hybrid LCVs/SCVs, for example, pick-up vehicles, and configured in accordance with the present invention, with the first bevel gear 20 fitted on the input shaft 10 at the primary drive stage 50 and second bevel gear 20 on the counter-shaft 30 and bevel gear 70 fitted at the final drive stage 60. The final drive stage 60 is connected to the output shaft 100 via transmission T for transferring optimal torque to the e-axle assembly of the electric powertrain of the LCV/SCV.

Figure 3 shows an enlarged view of the middle portion of the axle assembly of Figure 2 along with the electric motor (EM) mounted therewith. Here, at the primary drive stage 50, the first bevel gear 20 is fitted on the input shaft 10 of the electric motor EM and the second bevel gear 20 is fitted on the first end of the counter-shaft 30 and the second end of ther counter-shaft 30 is fitted with the final bevel gear 70 at the final drive stage 60. The final drive stage 60 is connected to the output shaft 100 via transmission T.

Figure 4 shows an e-axle assembly configured with bevel gear pair 20 at the primary drive stage 50 and the bevel gear 70 is fitted at the final drive stage 60 connected to the output shaft 100 via transmission T. In the e-axle assembly for electric powertrain of electric or hybrid LCVs/SCVs, for example, pick-up vehicles, the prime mover is the electric motor (EM) with its input shaft 10 connected thereto through splines. The torque is transferred from the electric motor (EM) to the input shaft 10 through the splines. The primary drive gear is a bevel gear integrated with the input shaft 10. Accordingly, the torque is transferred from the primary drive gear to the primary driven gear assembled on the counter-shaft 30 also connected through splines. The primary gear pair 50 is a combination of both drive and driven gear. The final drive pinion 70 is a hypoid pinion integrated with the counter-shaft. The torque transfer takes place from the final drive pinion 70 to the final drive gear, also a hypoid gear. The final drive FD gear pair 60 is a combination of pinion and gear. The final drive gear is mounted on the differential assembly through bolts. The LHS and RHS of output shaft 100 is connected to differential assembly through splines.

TECHNICAL ADVANTAGES AND ECONOMIC SIGNIFICANCE

The e-axle assembly for electric powertrain of electric or hybrid LCVs/SCVs configured in accordance with the present invention offers the following advantages:

a) Achieves higher gear-ratio and thus torque on wheels of LCV/SCVs.

b) Solves the packaging constraints of the e-axle assembly experienced in the conventional e-axle assembly having spur/helical gears at primary and final drive stage.

c) Cost-effective solution.

The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments.
It is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation. The exemplary embodiments described in this specification are intended merely to provide an understanding of various manners in which this embodiment may be used and to further enable the skilled person in the relevant art to practice this invention.

Although, the embodiments presented in this disclosure have been described in terms of its preferred embodiments, the skilled person in the art would readily recognize that these embodiments can be applied with modifications possible within the spirit and scope of the present invention as described in this specification by making innumerable changes, variations, modifications, alterations and/or integrations in terms of materials and method used to configure, manufacture and assemble various constituents, components, subassemblies and assemblies, in terms of their size, shapes, orientations and interrelationships without departing from the scope and spirit of the invention.

The numerical values given of various physical parameters, dimensions and quantities are only approximate values and it is envisaged that the values higher or lower than the numerical value assigned to the physical parameters, dimensions and quantities fall within the scope of the disclosure unless there is a statement in the specification to the contrary.

Throughout this specification, the word “comprise”, or variations such as “comprises” or “comprising”, shall be understood to imply including a described element, integer or method step, or group of elements, integers or method steps, however, does not imply excluding any other element, integer or step, or group of elements, integers or method steps.

The use of the expression “a”, “at least” or “at least one” shall imply using one or more elements or ingredients or quantities, as used in the embodiment of the disclosure in order to achieve one or more of the intended objects or results of the present invention.

The description of the exemplary embodiments is intended to be read in conjunction with the accompanying drawings, which are to be considered part of the entire written description. In the description, relative terms such as “lower”, “upper”, “horizontal”, “vertical”, “above”, “below”, “up”, “down”, “top”, and “bottom” as well as derivatives thereof (e.g. “horizontally”, “inwardly”, “outwardly”; “downwardly”, “upwardly” etc.) should be construed to refer to the orientation as then described or as shown in the drawing under discussion.
These relative terms are for convenience of description and do not require that the corresponding apparatus or device be constructed or operated in a particular orientation.

Terms concerning attachments, coupling and the like, such as “connected” and “interconnected”, refer to a relationship, wherein structures are secured or attached to one another either directly or indirectly through intervening structures, as well as both movable or rigid attachments or relationships, unless expressly described otherwise. , Claims:We claim:

1. An e-axle assembly for electric powertrain of an electric or hybrid Light/Small Commercial Vehicle (LCV/SCV), comprising:

• a primary stage (50) carrying a pair of bevel gears (20) engaged with an electric motor (EM);

• a counter-shaft (30) connecting said primary stage (50) to a final stage (60);

• said final stage (60) carrying a final bevel gear (70) mounted on said counter-shaft (30); and

• said final stage (60) connected to an output shaft (100) via a transmission (T);

wherein said electric motor (EM) is disposed parallel to said output shaft (100) for said transmission (T) and configured to optimally transfer torque to said output shaft (100).

2. The e-axle assembly as claimed in claim 1, wherein said primary stage (50) comprises a first bevel gear (20) mounted on an input shaft (10) of said electric motor (EM).

3. The e-axle assembly as claimed in claim 2, wherein said primary stage (50) comprises a second bevel gear (20) engaged with said first bevel gear (20) and mounted on said counter-shaft (30).

4. The e-axle assembly as claimed in claim 1, wherein said counter-shaft (30) is configured as a hypoid pinion or shaft.
5. The e-axle assembly as claimed in claim 1, wherein said final stage (60) is configured with a hypoid gear pair arrangement.

6. The e-axle assembly as claimed in claim 1, wherein said final stage (60) comprises a final bevel gear (70) mounted on said counter-shaft (30) and connected to said output shaft (100) via a transmission (T).

7. The e-axle assembly as claimed in claim 6, wherein said final stage (60) comprises a final bevel gear (70) mounted on said counter-shaft (30) configured as a hypoid pinion.

8. The e-axle assembly as claimed in claim 7, wherein said electric motor (EM) is disposed parallel to said output shaft (100) for said transmission (T).

9. The e-axle assembly as claimed in claim 8, wherein said electric motor (EM) optimally transfers torque at 900 to the axis of said output shaft (100).

10. The e-axle assembly as claimed in claim 8, wherein said e-axle assembly comprises:

• a primary stage (50) carrying a first bevel gear (20) engaged with said electric motor (EM), and a second bevel gear (20) engaged with said first bevel gear (20) and mounted on said counter-shaft (30);

• said counter-shaft (30) configured as a hypoid pinion or shaft connecting said primary stage (50) to said final stage (60);

• said final stage (60) is configured with a hypoid gear pair arrangement having a final bevel gear (70) mounted on said counter-shaft (30); and

• said final stage (60) connected to said output shaft (100) via said transmission (T);

wherein said electric motor (EM) is disposed parallel to said output shaft (100) for said transmission (T) and configured to optimally transfer torque at 900 to the axis of said output shaft (100).

Dated this 20th day of March 2023.

Digitally / e-Signed by:

(SANJAY KESHARWANI)
APPLICANT’S PATENT AGENT
REGN. NO. IN/PA-2043.