Claims:I/We claim
1. A powertrain mounting structure for mounting an electric powertrain in a vehicle, the powertrain mounting structure comprising:
a first powertrain mount to be coupled to the electric powertrain; and
a second powertrain mount to be coupled to the electric powertrain, wherein the first powertrain mount and the second powertrain mount are disposed such that, when the electric powertrain is mounted between the first powertrain mount and the second powertrain mount, a mount axis passing through the first powertrain mount and the second powertrain mount aligns with a torque roll axis (TRA) of the electric powertrain.
2. The powertrain mounting structure as claimed in claim 1, wherein the first powertrain mount and the second powertrain mount are diagonally displaced relative to each other.
3. An electric powertrain assembly for a vehicle, the electric powertrain assembly comprising:
an electric powertrain for driving the vehicle;
a first powertrain mount supporting the electric powertrain, the first powertrain mount being disposed above a top end of the electric powertrain and to a first side in a width direction of the electric powertrain; and
a second powertrain mount supporting the electric powertrain, the second powertrain mount being disposed below the top end of the electric powertrain and to a second side opposite the first side in the width direction of the electric powertrain.
4. The electric powertrain assembly as claimed in claim 3, wherein the first powertrain mount and the second powertrain mount are disposed such that a mount axis connecting the first powertrain mount and the second powertrain mount passes aligns with a torque roll axis (TRA) of the electric powertrain.
5. The electric powertrain assembly as claimed in claim 3, comprising:
a sub-frame disposed below the top end of the electric powertrain and extending in the width direction of the electric powertrain; and
a first saddle coupled to the sub-frame and extending in a length direction of the electric powertrain, wherein the second powertrain mount is mounted on the first saddle.
6. The electric powertrain assembly as claimed in claim 5, comprising a second saddle disposed on the first side of the electric powertrain and extending in the length direction of the electric powertrain.
7. The electric powertrain assembly as claimed in claim 5, comprising a third powertrain mount mounted on the sub-frame and coupled to the electric powertrain to support the electric powertrain, wherein the third powertrain mount is substantially equidistant from the first powertrain mount and the second powertrain mount in the width direction of the electric powertrain.
8. A vehicle comprising:
an engine bay;
an electric powertrain assembly housed in the engine bay, the electric powertrain assembly comprising:
an electric powertrain;
a first powertrain mount supporting the electric powertrain;
a second powertrain mount supporting the electric powertrain, the electric powertrain being mounted between the first powertrain mount and the second powertrain mount, wherein a mount axis passing through the first powertrain mount and the second powertrain mount aligns with a torque roll axis (TRA) of the electric powertrain.
9. The vehicle as claimed in claim 8, wherein the first powertrain mount is disposed above a top end of the electric powertrain and to a first side in a width direction of the electric powertrain and wherein the second powertrain mount is disposed below the top end of the electric powertrain and to a second side opposite the first side in the width direction of the electric powertrain.
10. The vehicle as claimed in claim 8, wherein the electric powertrain assembly comprises:
a sub-frame mounted on a floor of the engine bay; and
a first saddle disposed to the second side of the electric powertrain and coupled to the sub-frame, wherein the second powertrain mount is mounted on the first saddle.
11. The vehicle as claimed in claim 10, comprising a frontend module disposed forward of the sub-frame in a vehicle movement direction, wherein the electric powertrain assembly comprises a second saddle coupled to the sub-frame, the second saddle being disposed on the first side of the electric powertrain, and wherein the first saddle and the second saddle extend from the sub-frame and are coupled to the frontend module.
12. The vehicle as claimed in claim 8, comprising:
a firewall separating the engine bay from a passenger compartment of the vehicle;
a frontend module disposed forward of the planum in a vehicle movement direction;
a first long member extending from the firewall to the frontend module and coupled to the frontend module, wherein the first powertrain mount is disposed on the first long member.

Dated this 04th day of February 2022

GOPINATH ARENUR SHANKARARAJ
Of K&S Partners
IN/PA 1852
AGENT FOR THE APPLICANT
, Description:FORM 2
THE PATENTS ACT 1970
[39 OF 1970]
&
THE PATENTS RULES, 2003

COMPLETE SPECIFICATION
[See section 10; rule 13]

TITLE: “Mounting of Electric Powertrain in a Vehicle”

Name and Address of the Applicant: TATA MOTORS PASSENGER VEHICLES LIMITED, of Floor 3, 4, Plot-18, Nanavati Mahalaya, Mudhana Shetty Marg, BSE, Fort, Mumbai, Mumbai City, Maharashtra, 400001

Nationality: IN

The following specification particularly describes the invention and the manner in which it is to be performed.

MOUNTING OF ELECTRIC POWERTRAIN IN A VEHICLE

FIELD OF INVENTION
[001] The present invention relates to a vehicle, and more specifically related to mounting an electric powertrain in a vehicle.

BACKGROUND
[002] A vehicle, such as a car, may include an electric powertrain to drive the vehicle. The electric powertrain may include an electric motor and a transmission. A powertrain mounting structure may be utilized to mount the electric powertrain in the vehicle, such as in an engine bay of the vehicle. The powertrain mounting structure includes a plurality of powertrain mounts coupled to the electric powertrain for mounting the powertrain.
[003] The powertrain mounts may maintain the powertrain in a suspended state in the vehicle, to prevent vibrations occurring due to movement of the vehicle from getting transferred to the electric powertrain. The powertrain mounts may also prevent a movement of the electric powertrain, for example, in a linear direction. However, the powertrain mounts may be unable to prevent an oscillatory movement of the powertrain. The oscillations of the powertrain may cause noise and vibration.

SUMMARY
[004] A powertrain mounting structure for mounting an electric powertrain in a vehicle includes a first powertrain mount and a second powertrain mount to be coupled to the electric powertrain. The first powertrain mount and the second powertrain mount are disposed such that, when the electric powertrain is mounted between the first powertrain mount and the second powertrain mount, a mount axis passing through the first powertrain mount and the second powertrain mount aligns with a torque roll axis (TRA) of the electric powertrain.

BRIEF DESCRIPTION OF FIGURES
[005] The features, aspects, and advantages of the subject matter will be better understood with regard to the following description, and accompanying figures. The use of the same reference number in different figures indicates similar or identical features and components.
[006] Fig. 1 illustrates a vehicle, according to an implementation of the present subject matter.
[007] Fig. 2 illustrates a perspective view of a powertrain assembly, according to an implementation of the present subject matter.
[008] Fig. 3 illustrates a front view of a powertrain assembly, according to an implementation of the present subject matter.
[009] Fig. 4 illustrates a side view of a powertrain assembly, according to an implementation of the present subject matter.
[0010] Fig. 5 illustrates a top view of a powertrain assembly, according to an implementation of the present subject matter.
[0011] Fig. 6(a) illustrates a perspective view of a vehicle, according to an implementation of the present subject matter.
[0012] Fig. 6(b) illustrates a top view of a vehicle, according to an implementation of the present subject matter.
[0013] Fig. 7 illustrates a first saddle and a second saddle of a vehicle, according to an implementation of the present subject matter.

DETAILED DESCRIPTION OF INVENTION
[0014] The present subject matter relates to mounting of an electric powertrain in a vehicle. Using techniques of the present subject matter, oscillatory movement of the electric powertrain during movement of the vehicle can be reduced and prevented.
[0015] In accordance with an implementation of the present subject matter, a powertrain mounting structure includes a first powertrain mount and a second powertrain mount for supporting an electric powertrain between them. The first powertrain mount and the second powertrain mount are disposed such that, when the electric powertrain is mounted between them, a mount axis passing through the first powertrain mount and the second powertrain mount aligns with a torque roll axis (TRA) of the electric powertrain. TRA of the electric powertrain may refer to an axis about which the electric powertrain tends to rotate or oscillate when a torque excites the electric powertrain about a shaft of the powertrain. In an example, the first powertrain mount and the second powertrain mount are disposed on the TRA of the electric powertrain. In accordance with the example, the axis passing through the first powertrain mount and the second powertrain mount coincides with the TRA.
[0016] To enable alignment of the axis passing through the first powertrain mount and the second powertrain mount with the TRA, in an implementation, the first powertrain mount may be disposed above a top end of the electric powertrain and to a first side in a width direction of the electric powertrain. Further, the second powertrain mount may be disposed below the top end of the electric powertrain and to a second side opposite the first side in the width direction of the electric powertrain. For example, the first powertrain mount may be disposed at a top-right side of the electric powertrain and the second powertrain mount may be disposed at a bottom-left side of the electric powertrain.
[0017] In accordance with the present subject matter, the powertrain mounts are disposed close to, or on, the TRA of the electric powertrain. Therefore, oscillations of the electric powertrain about the TRA, which may otherwise occur when a torque excites the electric powertrain about the shaft, may be reduced. Thus, noise and vibrations arising during the movement of the vehicle are reduced.
[0018] The implementations herein and the various features and advantageous details thereof are explained more fully with reference to the non-limiting implementations that are illustrated in the accompanying drawings and detailed in the following description. It should be understood, however, that the following descriptions, while indicating preferred implementations and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the implementations herein without departing from the spirit thereof, and the implementations herein include all such modifications. The examples used herein are intended merely to facilitate an understanding of ways in which the implementations herein can be practiced and to further enable those skilled in the art to practice the implementations herein. Accordingly, the examples should not be construed as limiting the scope of the implementations herein.
[0019] Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the implementations herein. Also, the various implementations described herein are not necessarily mutually exclusive, as some implementations can be combined with one or more other implementations to form new implementations.
[0020] Referring now to the drawings, and more particularly to Figs. 1 through 7, where similar reference characters denote corresponding features consistently throughout the figures, there are shown preferred implementations. Further, for the sake of simplicity, and without limitation, the same numbers are used throughout the drawings to reference like features and components. The implementations herein will be better understood from the following description with reference to the drawings.
[0021] Fig. 1 illustrates a vehicle 100, according to an implementation of the present subject matter. The vehicle 100 may be, for example, a passenger vehicle, such as a car. In other examples, the vehicle 100 may be a commercial vehicle, such as a truck or a bus. In an example, the vehicle 100 may be an electric vehicle (EV). The vehicle 100 may include an electric powertrain assembly 102, also referred to as a powertrain assembly 102. The powertrain assembly 102 may be housed, for example, in an engine bay 104 of the vehicle 100. The term “engine bay” is merely used to indicate the position thereof in the vehicle 100, and does not indicate that the vehicle 100 includes an engine. For example, as mentioned above, the vehicle 100 may be an EV, which is devoid of an engine.
[0022] Fig. 2 illustrates a perspective view of a powertrain assembly 200, according to an implementation of the present subject matter. The powertrain assembly 200 may correspond to the powertrain assembly 102. The powertrain assembly 200 may be housed in a vehicle (not shown in Fig. 2), such as the vehicle 100. The powertrain assembly 200 may include an electric powertrain 202, also referred to as a powertrain 202, to drive the vehicle. In an example, the powertrain 202 includes an electric motor 204, also referred to as a motor 204, and a transmission 206. The motor 204 may be operatively coupled to the transmission 206. For instance, the transmission 206 may transfer drive from the motor 204 to drive wheels (not shown in Fig. 2) of the vehicle. The drive from the motor 204 may be transmitted to the transmission 206 through a shaft (not shown in Fig. 2). In an example, the transmission 206 may be an automatic transmission.
[0023] The powertrain assembly 200 may also include a powertrain mounting structure 208 for mounting the powertrain 202 in the vehicle, such as in the engine bay of the vehicle. The powertrain mounting structure 208 may support the powertrain 202 in a suspended state in the engine bay. That is, the powertrain 202 may not be in contact with, and may be above, a floor of the engine bay. The suspended state of the powertrain 202 prevents vibrations, which may occur when the vehicle is driven, from getting transferred from the floor of the engine bay to the powertrain 202.
[0024] The mounting structure 208 includes a first powertrain mount 210 and a second powertrain mount 212 that are coupled to and that support the powertrain 202. The first powertrain mount 210 may also be referred to as the first mount 210 and the second powertrain mount 212 may also be referred to as the second mount 212. In an example, the first mount 210 may be bolted to a first bracket 214 coupled to the motor 204 and the second mount 212 may be bolted to a second bracket 216 coupled to the transmission 206. The powertrain 202 may be mounted between the first mount 210 and the second mount 212.
[0025] The powertrain 202 may tend to rotate or oscillate about an axis 218 when a torque excites the powertrain 202 about the shaft that transmits drive from the motor 204 to the transmission 206. A torque may excite the powertrain 202 about the shaft, for example, when the vehicle is running or idling, when clutch is engaged, or when accelerator pedal is depressed and immediately released (i.e., during tip-in and tip-out). The axis may be referred to as a torque roll axis (TRA). The TRA 218 may depend on respective masses, centres of gravity, and inertias of the motor 204 and of the transmission 206. The TRA 218 passes through a centre of gravity (not shown in Fig. 2) of the powertrain 202. As will be appreciated, the powertrain 202 is to be prevented from rotating. The rotation of the powertrain 202 is prevented by the powertrain mounts, as they remain stationary relative to the vehicle during movement of the vehicle. The powertrain mounts are positioned such that they can reduce oscillatory motions of the powertrain 202 about the TRA 218 during movement of the vehicle, as will be explained below:
[0026] The first mount 210 and the second mount 212 may be mounted such that, when the powertrain 202 is mounted between the first mount 202 and the second mount 204, an imaginary line 220 passing through the first mount 210 and the second mount 212 is aligned with the TRA 218. The imaginary line 220 may also be referred to as a mount axis. The mount axis 220 being aligned with the TRA 218 may mean (i) that the mount axis 220 coincides with the TRA 218 (i.e., the imaginary line is same as the TRA 218), (ii) that the mount axis 220 intersects with the TRA 218 in a region between the first mount 210 and the second mount 212 and an angle between the mount axis 220 and the TRA 218 is small, such as less than 10°, or (iii) that the mount axis 220 is parallel to the TRA 218 and a distance between the imaginary line and the TRA 218 is small, such as less than 50 mm. In Fig. 1, the mount axis 220 coincides with the TRA 218. However, they are shown apart from each other to illustrate both the mount axis 220 and the TRA 218.
[0027] By virtue of the alignment of the mount axis 220 with the TRA 218, both the first mount 210 and the second mount 212 are close to the TRA 218. For instance, the first mount 210 and the second mount 212 may be located on the TRA 218 (if the mount axis 220 coincides with the TRA 218) or may be offset from the TRA 218 by a minimal distance, such as less than 50 mm. Since the powertrain mounts are disposed close to the TRA 218, the powertrain mounts can reduce oscillations of the powertrain 202 about the TRA 218. Further, if the powertrain mounts are disposed on the TRA 218, the oscillations may be eliminated.
[0028] In an implementation, to achieve the disposition of the powertrain mounts close to the TRA 218, the first mount 210 and the second mount 212 may be spaced apart from each other in a width direction ‘W’ of the powertrain 202. For example, the first mount 210 may be disposed at a first side 222, such as right-hand side, of the powertrain 202 in the width direction ‘W’ of the powertrain 202. Further, the second mount 212 may be disposed to a second side 224, such as left-hand side, of the powertrain 202 in the width direction ‘W’ of the powertrain 202, where the second side 224 is opposite the first side 222. In addition, the first mount 210 and the second mount 212 may be spaced apart from each other in a height direction ‘H’ of the powertrain 202. For example, the first mount 210 may be disposed above a top end 226 of the powertrain 202 and the second mount 212 may be disposed below the top end 226. By virtue of displacement from each other in width and height directions of the powertrain 202, the first mount 210 and the second mount 212 are diagonally displaced relative to each other. In an example, the width direction ‘W’ and height direction ‘H’ of the powertrain 202 are same as the width direction and the height direction, respectively, of the vehicle in which the powertrain 202 is mounted.
[0029] To dispose the first mount 210 above the top end 226, in an implementation, the first mount 210 may be mounted on a first long member 228 of the vehicle. The first long member 228 may be disposed to the first side 222 of the powertrain 202 and may extend along a length direction ‘L’ of the powertrain 202. The length direction ‘L’ of the powertrain 202 may be same as that of the vehicle. The first long member 228 may be supported by a firewall of the vehicle, as will be explained with reference to Figs. 6(a) and 6(b). Further, to support the second mount 212 below the top end 226, a first saddle 230 may be provided in the powertrain assembly 200. The first saddle 230 may be provided to the second side 224 of the powertrain 202 and the second mount 212 may be mounted on the first saddle 230.
[0030] The first saddle 230 may be coupled to a sub-frame 232 that may be disposed below the top end 226 of the powertrain 202. The sub-frame 232 may be mounted on the floor of the engine bay. The sub-frame 232 may extend in the width direction ‘W’ of the powertrain 202 and may include a first mounting provision 234 and a second mounting provision 236 at its ends. Each mounting provision may include an opening through which fasteners can be inserted to fasten the sub-frame to the floor of the engine bay. In an example, the first saddle 230 extends from an end of the sub-frame 232 in the second side 224 towards a front of the vehicle, in the length direction ‘L’.
[0031] As illustrated, by mounting the first mount 210 on the first long member 228 and by mounting the second mount 212 on the first saddle 230, the first mount 210 and the second mount 212 are disposed on the TRA 218. In an implementation, the powertrain mounting structure 208 may include a third powertrain mount 238, also referred to as a third mount 238, coupled to the powertrain 202 to support the powertrain 202. The third mount 238 may be coupled to a middle part of the powertrain 202 in the width direction ‘W’. Accordingly, the third mount 238 may be substantially equidistant from the first mount 210 and the second mount 212 in the width direction ‘W’. For instance, a distance 240 between the third mount 238 and the second mount 212 in the width direction ‘W’ may be substantially same as a distance 242 between the third mount 238 and the first mount 210 in the width direction ‘W’. In an example, the third mount 238 may be mounted on the sub-frame 232, and may be away from the TRA 218.
[0032] Fig. 3 illustrates a front view of the powertrain assembly 200, according to an implementation of the present subject matter. The first mount 210 and the second mount 212 may be diagonally displaced from each other, and the TRA 218 of the powertrain 202 may pass through both the first mount 210 and the second mount 212. Here, the mount axis 220 is not shown because the mount axis 220 coincides with the TRA 218.
[0033] Fig. 4 illustrates a side view of the powertrain assembly 200, according to an implementation of the present subject matter. The powertrain assembly 200 includes the first saddle 230 on which the second mount 212 is mounted. Further, the third mount 238 may be mounted on the sub-frame 232.
[0034] Fig. 5 illustrates a top view of the powertrain assembly 200, according to an implementation of the present subject matter. As illustrated, the first mount 210 is mounted on the first long member 228 and is bolted to a first bracket 214 coupled to the motor 204. Further, the second mount 212 is mounted on the first saddle 230 (not shown in Fig. 5), extends in the width direction ‘W’ from the first saddle 230, and bolted to the second bracket 216, which is coupled to the transmission 206. Above the first saddle 230, a second long member 502 may be disposed. The second long member 502 may be disposed at the same height as the first long member 228 and may be disposed on the second side 224 of the powertrain 202.
[0035] Fig. 6(a) illustrates a perspective view of a vehicle 600, according to an implementation of the present subject matter. The vehicle 600 may correspond to the vehicle 100. Here, the roof, doors, and various other parts of the vehicle 600 are not illustrated. The vehicle 600 may include a firewall 602 that separates a passenger compartment 604 of the vehicle 600 from an engine bay 606. A frontend module 608 may be disposed forward of the firewall 602 in a vehicle movement direction, i.e., in the length direction ‘L’ of the vehicle 600. The frontend module 608 may be provided at the front of the vehicle 600 and may provide support and safety in the case of an accident. The vehicle 600 includes a powertrain assembly 610 housed in the engine bay 606. The powertrain assembly 610 may correspond to the powertrain assembly 200.
[0036] Fig. 6(b) illustrates a top view of vehicle 600, according to an implementation of the present subject matter. The powertrain assembly 610 includes a powertrain 612 having a motor 614 and a transmission 616. The powertrain 612 is mounted in the engine bay 606 using a first mount 618 and a second mount 620, which correspond to the first mount 210 and the second mount 212. The first mount 618 may be mounted on a first long member 622, which corresponds to the first long member 228, and the second mount 620 is mounted on a first saddle (not shown in Fig. 6(b)), which corresponds to the first saddle 230. Above the first saddle 230, a second long member 624, corresponding to the second long member 502, may be disposed. Similarly, below the first long member 622, a second saddle (not shown in Fig. 6(b)) may be disposed.
[0037] The first long member 622 and the second long member 624 may be coupled to and be supported by the firewall 602. Further, the first long member 622 and the second long member 624 may extend in the length direction ‘L’ (i.e., movement direction) of the vehicle 600 from the firewall 602 towards the front of the vehicle 600. The respective other ends of the first long member 622 and the second long member 624 may be coupled to the frontend module 608. Since the long members are in contact with the frontend module 608, they provide additional stability to the vehicle 600 in the case of an accident. For instance, in case of a collision from the front (i.e., frontal crash) of the vehicle 600, the energy from the collision is transferred by the frontend module 608 to the long members and is absorbed by the long members.
[0038] Fig. 7 illustrates a first saddle 702 and a second saddle 704 of the vehicle 600, according to an implementation of the present subject matter. The first saddle 702 may be disposed below the second long member 624 and the second saddle 704 may be disposed below the first long member 622 (not shown in Fig. 7). The first saddle 702 and the second saddle 704 may be coupled to a sub-frame 706, which may correspond to the sub-frame 232. The sub-frame 706 may be disposed below the firewall 602 (not shown in Fig. 7), and rearward of the frontend module 608 (not shown in Fig. 7) in the length direction ‘L’ of the vehicle 700.
[0039] The first saddle 702 and the second saddle 704 may be disposed at opposite sides in the width direction ‘W’ of the powertrain 612 (not shown in Fig. 7). For example, the second saddle 704 may be disposed to a first side and the first saddle 702 may be disposed to a second side of the powertrain 612.
[0040] The first saddle 702 may be coupled to the sub-frame 706 through a first joinery bracket 708 and the second saddle 704 may be coupled to the sub-frame 706 through a second joinery bracket 710. From their respective joinery brackets, the first saddle 702 and the second saddle 704 may extend towards the front of the vehicle 600. Further, at their respective forward ends, the first saddle 702 and the second saddle 704 are provided with mounting provisions for being coupled to the frontend module 608. The mounting provisions may be, for example, openings through which fasteners can be inserted for being coupled to the frontend module 608. For instance, the first saddle 702 may include openings 712-1 and 712-2 and the second saddle 704 may include openings 714-1 and 714-2 to receive the fasteners.
[0041] Since the saddles are provided in contact with the frontend module 608, the saddles also act as energy absorbing members in case of an accident, similar to the long members. Thus, the provision of the saddles not only enables mounting the powertrain mounts along the TRA, but also increases the crash safety of the vehicle 600.
[0042] The present subject matter enables preventing oscillations of the electric powertrain about the TRA during, for example, travelling of the vehicle, idling, clutch engagement, and tip-in and tip-out of accelerator pedal. Therefore, noise and vibrations of the electric powertrain can be considerably reduced, and NVH (noise, vibration, and harshness) characteristics of the vehicle are improved both in static and transient scenarios. Further, the provision of the saddles also enables absorbing energy in case of a collision of the vehicle. Therefore, transfer of the energy to passengers of the vehicle can be significantly reduced, thereby increasing safety of the passengers. Further, the weight of the frontend module can be reduced, as crash impact is shared with the frontend module by the saddles.
[0043] The foregoing description of the specific implementations will so fully reveal the general nature of the implementations herein that others can, by applying current knowledge, readily modify and/or adapt for various applications without departing from the generic concept, and, therefore, such modifications and adaptations should and are intended to be comprehended within the meaning and range of equivalents of the disclosed implementations. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the implementations herein have been described in terms of preferred implementations, those skilled in the art will recognize that the implementations herein can be practiced with modification within the spirit and scope of the implementations as described herein.