WO2020152639A1

WO2020152639A1 - A powertrain mounting assembly

Info

Publication number: WO2020152639A1
Application number: PCT/IB2020/050562
Authority: WO
Inventors: Hemant Prabhune; Nitin Gupta; Amol DESHPANDE
Original assignee: Piaggio & C.S.P.A.
Priority date: 2019-01-25
Filing date: 2020-01-24
Publication date: 2020-07-30
Also published as: EP3914465A1; EP3914465A4

Abstract

The present disclosure envisages a mounting assembly (300, 400, 500) for mounting a powertrain (100) on the rear of the chassis (200) of a three-wheeled vehicle. The mounting assembly (300, 400, 500) comprises a bracket and an anti-vibration mount (380, 480, 580). The bracket (320, 420, 520) is configured to be attached to the powertrain (100). The anti-vibration mount (380, 480, 580) is coupled to the bracket (320, 420, 520) and is configured to be attached to the chassis (200) of the vehicle. Also envisaged is a mounting arrangement which includes at least three mounting assemblies (300, 400, 500) for mounting the powertrain (100) on the chassis (200) of the vehicle. The mounting assembly isolates vibration of the powertrain from transmitting to the vehicle chassis, enhances comfort of the passenger and is convenient for installation.

Description

A POWERTRAIN MOUNTING ASSEMBLY

FIELD

The present disclosure relates to automobiles. In particular, the disclosure relates to mounting arrangement of an automobile powertrain. BACKGROUND

The background information herein below relates to the present disclosure but is not necessarily prior art.

Vibrations generated in a vehicle powertrain originate are because of crank train unbalanced forces and combustion reactions. In a three-wheeled vehicle like an auto-rickshaw (tuk-tuk), the engine along with rest of the components of the powertrain is conventionally mounted in the rear side of the engine, under the passenger seat and above the rear shaft. Body of an auto-rickshaw chassis is majorly made out of sheet metal. When the vibration from the powertrain transmits to the chassis, the customer comfort deteriorates not only due to chassis vibration but also due to noise of the vehicle body sheets. The higher amplitudes of an engine’s vibration could aggravate the discomfort further, if not isolated properly. Higher amplitudes of vibration are also detrimental to the life of various components of the vehicle chassis.

Therefore, there is a need of a mounting arrangement for a powertrain in a compact vehicle such as a three- wheeled vehicle, which ameliorates the aforementioned issues. OBJECTS

Some of the objects of the present disclosure, which at least one embodiment herein satisfies, are as follows:

A primary object of the present disclosure is to provide a powertrain mounting arrangement for a compact vehicle. Another object of the present disclosure is to provide a powertrain mounting arrangement for a compact vehicle, which isolates vibration of the powertrain from transmitting to the vehicle chassis and rest of the vehicle body and parts. Yet another object of the present disclosure is to provide a powertrain mounting arrangement for a compact vehicle, which enhances comfort of the passenger.

Other objects and advantages of the present disclosure will be more apparent from the following description, which is not intended to limit the scope of the present disclosure. SUMMARY

The present disclosure envisages a mounting assembly for mounting a powertrain (on the rear of the chassis of a three-wheeled vehicle. The mounting assembly comprises a bracket and an anti-vibration mount. The bracket is configured to be attached to the powertrain. The anti vibration mount is coupled to the bracket and is configured to be attached to the chassis of the vehicle.

In an embodiment, the anti-vibration mount comprises a damping bush and a structural part. The structural part is configured to be attached to the chassis of the vehicle. Preferably, the damping bush comprises an inner sleeve, a bushing and an outer sleeve. The bushing is provided with a circular slot and at least a pair of rhombic cavities, wherein the circular slot is configured to receive a pin for coupling the bushing with a corresponding bracket and the rhombic cavities are configured to accommodate deformation on application of lateral load on the bushing. Moreover, the structural part comprises a pair of support flanges, an outer collar and a pair of stopper restings. Each of the brackets has a plurality of powertrain- side holes for allowing insertion of threaded fasteners for fitting the brackets on the powertrain and a plurality of chassis-side holes for insertion of pins passing through the corresponding damping bush.

In an embodiment, each of the chassis-side holes is provided with friction-resistant linings.

The present disclosure also envisages a mounting arrangement which includes at least three mounting assemblies for mounting the powertrain on the chassis of the vehicle. In a preferred embodiment, the mounting arrangement comprises two mounting assemblies disposed in an operative front side and a third mounting assembly disposed in an operative rear side of the powertrain. BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING

The powertrain mounting arrangement of the present disclosure will now be described with the help of the accompanying drawing, in which:

Figure 1 illustrates an isometric view of a powertrain mounting arrangement of the present disclosure;

Figure 2 illustrates an exploded view of the powertrain mounting arrangement of Figure 1 ;

Figure 3 illustrates an exploded view of the first mounting assembly of Figures 1 and 2;

Figure 4 illustrates an exploded view of the second mounting assembly of Figures 1 and 2;

Figure 5 illustrates an exploded view of the third mounting assembly of Figures 1 and 2; Figure 6 illustrates a AVM (anti vibration mount) sub-assembly of Figures 3, 4 and 5;

Figure 7 (including Figures 7a, and 7b) illustrates an exploded view of the AVM (anti vibration mount) sub-assembly of Figure 6;

Figure 8 (including Figures 8a, 8b and 8c) illustrates an exploded view of the damping bush sub-assembly of Figure 7a; Figure 9 illustrates an exploded view of structured part of AVM of Figure 7b;

Figure 10 illustrates a front view of the vehicle chassis showing the first and the second mounting assemblies of the present disclosure;

Figure 11 illustrates a rear view of the vehicle chassis showing the first and the third mounting assembly of the present disclosure; Figure 12 illustrates a top view of the vehicle chassis showing the first, second and third mounting assemblies of the present disclosure; and

Figure 13 illustrates an isometric view of the vehicle chassis showing the first, second and third mounting assemblies of the present disclosure. LIST OF REFERENCE NUMERALS

100 powertrain

200 chassis

220 clamping bracket

240 horizontal member

300 first mounting assembly

320 first bracket

322 first bracket powertrain-side hole

324 first bracket chassis-side hole 380 first anti-vibration mount (AVM)

340 first-damping bush of AVM

360 first structural part of AVM

400 second mounting assembly

420 second bracket

422 second bracket powertrain-side hole

424 second bracket chassis-side hole

480 second AVM

440 second damping bush of AVM

460 second structural part of AVM 500 third mounting assembly

520 third bracket

522 third bracket powertrain-side hole

524 third bracket chassis-side hole 580 third AVM

540 third damping bush of AVM

560 third structural part of AVM

562 third collar hole

80 an exemplary anti-vibration mount (AVM) 67 axial stopper

40 bushing subassembly

41 inner sleeve

42 inner sleeve slot

43 bushing

44 bushing slot

45 bushing cavity

46 outer sleeve

47 outer sleeve slot

60 collar subassembly

61 support flange

62 support flange hole

63 outer collar

64 outer collar slot

65 stopper resting

66 stopper resting groove

DETAILED DESCRIPTION Embodiments, of the present disclosure, will now be described with reference to the accompanying drawing.

Embodiments are provided so as to thoroughly and fully convey the scope of the present disclosure to the person skilled in the art. Numerous details are set forth, relating to specific components, and methods, to provide a complete understanding of embodiments of the present disclosure. It will be apparent to the person skilled in the art that the details provided in the embodiments should not be construed to limit the scope of the present disclosure. In some embodiments, well-known processes, well-known apparatus structures, and well-known techniques are not described in detail. The terminology used, in the present disclosure, is only for the purpose of explaining a particular embodiment and such terminology shall not be considered to limit the scope of the present disclosure. As used in the present disclosure, the forms“a”,“an” and“the” may be intended to include the plural forms as well, unless the context clearly suggests otherwise. The terms“comprises”,“comprising”,“including” and“having” are open-ended transitional phrases and therefore specify the presence of stated features, elements, modules, units and/or components, but do not forbid the presence or addition of one or more other features, elements, components, and/or groups thereof. The particular order of steps disclosed in the method and process of the present disclosure is not to be construed as necessarily requiring their performance as described or illustrated. It is also to be understood that additional or alternative steps may be employed.

When an element is referred to as being“mounted on”, “engaged to”, “attached to”, “connected to” or“coupled to” another element, it may be directly on, engaged, attached, connected or coupled to the other element. As used herein, the term“and/or” includes any and all combinations of one or more of the associated listed elements. The terms first, second, third, etc., should not be construed to limit the scope of the present disclosure as the aforementioned terms may be only used to distinguish one element, component, region, layer or section from another component, region, layer or section. Terms such as first, second, third etc., when used herein do not imply a specific sequence or order unless clearly suggested by the present disclosure. Terms such as“inner”,“outer”,“beneath”,“below”,“lower”,“above”,“upper” and the like, may be used in the present disclosure to describe relationships between different elements as depicted from the figures.

When a diesel engine, which produces high vibration levels and a large number of modes, is implemented in a compact vehicle such as a three-wheeled auto-rickshaw, the mounting arrangement of the powertrain becomes critical so as to ensure maximum comfort of the passenger. In terms of NVH performance, it is required that the vibrations from the rear- mounted powertrain be prevented from transmitting to the chassis of the vehicle, which majorly comprises a sheet metal body.

The powertrain mounting arrangement of the present disclosure is explained with the help of Figures 1 and 2, wherein the arrows indicate the longitudinal (front-rear) direction of the vehicle. The mounting arrangement with respect to the vehicle chassis 200 is illustrated in Figures 10, 11, 12 and 13. The three -point mounting arrangement for a rear-mounted powertrain 100 in a three-wheeled vehicle of the present disclosure is illustrated in the isometric view of Figure 1 and the exploded view of Figure 2, wherein each location of mounting is provided with a mounting assembly. The powertrain 100 comprises of an engine, a connecting rod, a crankshaft, a belt drive among other components. Out of the three mounting assemblies for mounting the powertrain 100 on the vehicle chassis 200, two mounting assemblies - the first mounting assembly 300 and the second mounting assembly 400 - is disposed in an operative front side of the powertrain 100 and the third mounting assembly 500 is disposed in an operative rear side. Each of the mounting assemblies 300, 400, 500 comprises a bracket and an anti-vibration mount. The bracket is configured to be attached to the powertrain 100. The anti- vibration mount is coupled to the bracket and is configured to be attached to the chassis 200 of the vehicle.

In an embodiment, the first mounting assembly 300, which is shown in Figure 3, comprises a first bracket 320 and a first damping bush 340 of a first anti- vibration mount (AVM) 380. The first bracket 320 of the first mounting assembly 300 is configured to be fitted substantially at the operative front and left end of the powertrain 100 of the vehicle, as shown in Figure 1 and Figure 2. The first damping bush 340 is inserted into a first structural part 360. The first structural part 360 is attached to the vehicle chassis 200 by means of threaded fasteners. Similarly, the second mounting assembly 400, which is shown in Figure 4, comprises a second bracket 420 and a second damping bush 440 of a second anti-vibration mount (AVM) 480. The second bracket 420 of the second mounting assembly 400 is configured to be fitted substantially at the operative front and right end of the powertrain 100 of the vehicle, as shown in Figure 1 and Figure 2. The second damping bush 440 is inserted into a second structural part 460. The second structural part 460 is attached to the vehicle chassis 200 by means of threaded fasteners. The third mounting assembly 500 shown in Figure 5, comprises a third bracket 520 and a third damping bush 540 of a third anti vibration mount (AVM) 580. As shown in Figure 1 and Figure 2, the third bracket 520 of the third mounting assembly 500 is configured to be fitted at the operative rear end of the powertrain 100 substantially centrally along the lateral mass distribution of the powertrain 100. The third damping bush 540 is inserted into a third structural part 560. The third structural part 560 is attached to the vehicle chassis 200 by means of threaded fasteners. In an embodiment, the third structural part 560 is linked to a horizontal member 240 which is in turn attached to the vehicle chassis 200. Each of the brackets 320, 420, 520 has a plurality of powertrain- side holes 322, 422, 522 respectively for allowing insertion of threaded fasteners to fit the brackets onto the available surfaces on the components of the powertrain 100. Another pair of opposing chassis-side holes 324, 424, 524 with friction-resistant linings is provided on each of the brackets 320, 420, 520 for insertion of pins passing through the respective damping bushes 340, 440, 540.

The brackets 320, 420, 520 can be of various shapes and dimensions based on the engineering requirements of the vehicle.

Figure 6 illustrates an exemplary anti-vibration mount (AVM) 80 which comprises a damping bush 40 and a structural part 60.

Figure 8, which includes Figures 8a, 8b and 8c, illustrates an exploded view of the damping bush 40 like the damping bushes 340, 440 or 540. As seen in Figure 8, the damping bush 40 comprises an inner sleeve 41, a bushing 43 and an outer sleeve 46. The inner sleeve 41 has a slot 42 defined for passing a pin therethrough, as shown in Figure 8a. The bushing 43 has a slot 44 defined for inserting and fixing the inner sleeve 41 therein, as shown in Figure 8b. The bushing also has cavities 45 provided for enhancing elasticity. The outer sleeve 46 has a slot 47 defined for inserting and fixing the bushing 43 therein, as shown in Figure 8c. The damping bush 40 is completed by press-fitting the components 41, 43 and 46 into one another. The inner sleeve 41 and the outer sleeve 46 are made of a metallic material such as aluminium, and the bushing 43 is made out of an elastomeric material selected from a group consisting of rubber - both natural and synthetic - such as neoprene, buna-n, among others. A pin that passes through the inner sleeve 41 can pass through the corresponding hole (e.g., holes 324, 424, 524 in brackets 320, 420, 520 respectively) in the corresponding bracket which thereby is fixed with the powertrain 100.

Figure 9, which includes Figures 9a, 9b, 9c, 9d, illustrates an exploded view of a structural part 60 like the structural part 360, 460 or 560 of the AVMs 380, 480, 580 respectively. As seen in Figure 9, the structural part 60 comprises a pair of support flanges 61, an outer collar 63 and a pair of stopper restings 65 (stopper 67 shown in Figure 7). The support flanges 61 are provided with holes 62 for allowing mounting using threaded fasteners onto clamping brackets 220, as shown in Figures 9a and 9b. The collar 63 has a slot 64 defined for inserting and fixing the damping bush 40 therein, as shown in Figure 9c. Each of the stopper resting 65 has a groove 66 defined therein for resting the stopper 67 therein, as shown in Figure 9d. The structural part 60 is completed by welding the components 61, 63 and 65 onto one another. The stopper resting 65 is configured to hold the stoppers 67 (shown in Figure 7) in position, pressing against the bushing 43 on both sides. The support flange 61 is made out of cast iron and the like, the outer collar 63 and the stopper resting 65 are made out of aluminium and the like.

The orientation of the damping bushes 340, 440, 540 are such that not only modes of vibration of the powertrain 100 which are dominant in the Z-direction, but also modes dominant in the X-direction, the Y-direction and those along the roll, pitch and yaw axes are cancelled. As a result, optimum isolation of vibration between the powertrain 100 and the vehicle chassis 200 is achieved. The vehicle body, therefore, does not rattle even if an engine with high amplitudes of vibration such as a diesel engine is used to propel the vehicle. Hence, the passengers experience a softer, quieter and more comfortable ride. The durability of various components of the vehicle, which otherwise would be subjected to high amplitudes of vibration, is also enhanced. Also, the installation of the powertrain becomes simplified as a result of the three -point mounting arrangement of the present disclosure.

In an embodiment, the cross section of the bushing 43 is circular. In another embodiment, a circular slot 44 and at least a pair of rhombic cavities 45 are provided across the width of each of the bushing. A pin is inserted through the circular slot 44 to couple each of the bushings with the corresponding brackets 320, 420, 520 respectively. The rhombic cavities 45 are mirror images of each other as seen in the side view. A lateral component of a load in the pin causes deformation along the rhombic cavities 45 due to the elastomeric property of the bushing material, which, in combination with the air contained therein, acts as a damping means.

The stiffness of the bushings, the proportion of size with respect to that of the bushing and shape of the rhombic through-slots, and other design parameters of the bushing have been calculated for cancellation of optimum number of vibration modes of the powertrain.

While the embodiments described hereinabove have been envisaged for a three-wheeled vehicle, the powertrain mounting arrangement of the present disclosure can also be implemented for a compact four-wheeled vehicle with a rear-mounted powertrain.

The foregoing description of the embodiments has been provided for purposes of illustration and not intended to limit the scope of the present disclosure. Individual components of a particular embodiment are generally not limited to that particular embodiment, but, are interchangeable. Such variations are not to be regarded as a departure from the present disclosure, and all such modifications are considered to be within the scope of the present disclosure.

TECHNICAL ADVANCEMENTS

The present disclosure described herein above has several technical advantages including, but not limited to, the realization of a powertrain mounting assembly for a compact vehicle, which:

• isolates vibration of the powertrain from transmitting to the vehicle chassis;

• enhances comfort of the passenger; and

• is convenient for installation.

The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein. The foregoing description of the specific embodiments 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 understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.

The use of the expression“at least” or“at least one” suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the disclosure to achieve one or more of the desired objects or results.

Any discussion of materials, devices, articles or the like that has been included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all of these matters form a part of the prior art base or were common general knowledge in the field relevant to the disclosure as it existed anywhere before the priority date of this application.

While considerable emphasis has been placed herein on the components and component parts of the preferred embodiments, it will be appreciated that many embodiments can be made and that many changes can be made in the preferred embodiments without departing from the principles of the disclosure. These and other changes in the preferred embodiment as well as other embodiments of the disclosure will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation.

Claims

CLAIMS:

1. A mounting assembly for use in mounting a powertrain (100) on the rear of the chassis (200) of a three -wheeled vehicle, wherein said mounting assembly (300, 400, 500) comprises: a. a bracket (320, 420, 520) configured to be attached to said powertrain (100); and b. an anti-vibration mount (380, 480, 580) coupled to said bracket (320, 420, 520) and configured to be attached to the chassis (200) of the vehicle.

2. The mounting assembly as claimed in claim 1, wherein said anti-vibration mount (380, 480, 580) comprises a damping bush (340, 440, 540) and a structural part (360,

460, 560), said structural part (360, 460, 560) been configured to be attached to the chassis (200) of the vehicle.

3. The mounting assembly as claimed in claim 2, wherein said damping bush comprises an inner sleeve (41), a bushing (43) and an outer sleeve (46). 4. The mounting assembly as claimed in claim 3, wherein said bushing (43) is provided with a circular slot (44) and at least a pair of rhombic cavities (45), wherein said circular slot (44) is configured to receive a pin for coupling said bushing (43) with a corresponding bracket and said rhombic cavities (45) are configured to accommodate deformation on application of lateral load on said bushing (43). 5. The mounting assembly as claimed in claim 2, wherein said structural part comprises a pair of support flanges (61), an outer collar (63) and a pair of stopper restings (65).

6. The mounting assembly as claimed in claim 2, wherein said bracket (320, 420, 520) has a plurality of powertrain-side holes (322, 422, 522) for allowing insertion of threaded fasteners for fitting said brackets (320, 420, 520) on the powertrain (100) and a plurality of chassis-side holes (324, 424, 524) for insertion of pins passing through the corresponding damping bush (340, 440, 540).

7. The mounting assembly as claimed in claim 6, wherein each of said chassis-side holes (324, 424, 524) is provided with friction-resistant linings.

8. A mounting arrangement as claimed in any of the above claims, which includes at least three mounting assemblies for mounting the powertrain (100) on the chassis (200) of the vehicle.

9. The mounting arrangement as claimed in claim 8, wherein said mounting arrangement comprises two mounting assemblies (300, 400) disposed in an operative front side and a third mounting assembly (500) disposed in an operative rear side of said powertrain

(100).