DESC:TECHNICAL FIELD
[0001] The present subject matter relates to a vehicle. More particularly, the present subject matter relates to a rear suspension system for a three-wheeled vehicle.
BACKGROUND
[0002] In many of the developing & under developed countries, a motor vehicle particularly a three-wheeled automotive vehicle is a significant mode of public transportation. It is vastly used as a point to point mode of transport of both goods and persons from one place to other in rural as well as in urban areas. Different models of the three-wheeled vehicle using petrol or diesel are manufactured and sold in the various developing markets. In addition, there are variants that can run on CNG (Compressed Natural Gas) or LPG (Liquefied Petroleum Gas). They usually run on 2 stroke engines which are inherently more polluting than the regular 4-stroke engine. Thus, various alternative energy vehicles have been proposed to revamp a large section of public transport to extend mileage and reduce emissions problems by replacing conventional fuel based engine operation to electric. Electric three-wheeled vehicle have become one of the preferred modes of transport between short distances and are operating in major urban and suburban areas.
[0003] Generally, the electric conversion of the conventional petrol-diesel three-wheeled vehicle involves removing the entire internal combustion engine from the vehicle, installing the electric motor in its place, and also adding a large bank of batteries. Further, the electric conversion involves a wide range of modification of systems, subsystem, parts and components of the vehicle which further has impact on costs, mileage, fuel economy, efficiency and emissions. In a known electric three-wheeled vehicle, a basic layout for an electric vehicle is tuned with different size motors, batteries, and a motor controller for each motor and batteries, wheels and suspension.
[0004] Although an electric three-wheeled vehicle have numerous advantages over conventional petrol and diesel three-wheeled vehicle, however, it is desirable that the electric three-wheeled vehicle should be cost effective, increases fuel economy with substantial reduction in emissions and simultaneously facilitates better performance and aesthetic modifications with key design features. Further, the modification of systems and subsystems should involve less number of parts and components so as to impart simple, light and easy construction which can require less maintenance and in addition provides a high level of strength and stiffness.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] The detailed description is described with reference to the accompanying figures. The same numbers are used throughout the drawings to reference like features and components.
[0006] Fig. 1 is a side view of a three-wheeled vehicle according to one embodiment of the present invention.
[0007] Fig. 2 is a perspective rear view of the three-wheeled vehicle as per one embodiment of the present invention.
[0008] Fig. 3 is a perspective view of a rear suspension system of the three-wheeled vehicle including a trailing arm assembly, as per one embodiment of the present invention.
[0009] Fig. 4 is a top view of the rear suspension system of Fig. 3 with a front portion of said trailing arm assembly mounted to at least a portion of a vehicle frame.
[00010] Fig. 5 is a perspective view of the trailing arm assembly including pair of trailing arms, as per one embodiment of the present invention.
[00011] Fig. 6 is an exploded view of the trailing arm assembly illustrating at least one mounting bracket, at least one hanger bracket and at least one receiving bracket, as per one embodiment of the present invention.
[00012] Fig.7 is an exploded view of the trailing arm assembly illustrating at least one mounting bracket and at least one hanger bracket, as per one embodiment of the present invention.
DETAILED DESCRIPTION
[00013] The three-wheeled serves as the most affordable means of transportation to the local people. Due to its small size, it is well suited for the narrow crowded streets in Indian cities & other similar markets. Basically, the vehicle is available in three variants- LPG (Liquefied Petroleum Gas), CNG (Compressed Natural Gas) and Diesel. Thus, the main concern of this vehicle has been its large emissions of green house gases and other toxic particulates, thereby causing severe air pollution.
[00014] An electric three-wheeled vehicle is becoming a good alternative to petrol and diesel three-wheeled vehicle due to its efficient performance and zero emission causing low pollution. Typically, the vehicle is operated by a highly efficient electric drive motor.
[00015] With conversion of petrol and diesel three-wheeled vehicle to electric one, various systems, subsystems and parts of the vehicle has undergone modifications to impart better performance with light and simple construction. Each system, though primarily independent, is influenced by the effect of other systems interacting with it. For example, a suspension system of the vehicle plays an important role in improving the fuel efficiency by maintaining a continuous contact of the wheels with the road and thereby preventing rolling slip. In addition, the suspension enhances the life of all components which are mounted on a vehicle frame. Thus, various technological improvements are constantly being made to optimize the suspension system, thereby imparting it more efficient and durable structure. Generally, the design of front and rear suspension of the vehicle is typically different.
[00016] Typically, a rear suspension system for the three-wheeled vehicle with the internal combustion engine mounted on a frame of the vehicle comprises of a trailing arm assembly independently suspended with a pair of rear wheels to move independent of the other to improve handling and ride comfort. The independent trailing arms together with a spring and shock absorber unit lies longitudinally in the driving direction and has a triangular form with the smaller part by the wheel and is therefore highly subjected to bending and torsional stress.
[00017] In a known two-wheeled vehicle, a trailing arm assembly adapted for suspending a body of said vehicle with respect to said pair of rear wheels, includes a front portion assembled to a vehicle frame as a revolute joint which swings whenever vehicle goes through uneven surface and a rear portion is fixedly attached to a rear axle housing bracket through welding. Further, a power train assembly including an engine, gearbox and differential are mounted on a rear portion of the vehicle frame. Thus, power transmission to each of said pair of rear wheels is through a propeller shaft and one or more muffcups. Thus, the conventional arrangement of the trailing arm structure in the conventional three-wheeled vehicle involves more assembling time, more number of parts and additionally complicates the mounting mechanism for said trailing arm assembly to said vehicle, thereby increasing the overall weight of the vehicle body with complex structure.
[00018] Hence, in order to design a light weight, high strength, and ergonomically efficient electric three-wheeled vehicle which can provide substantial reduction in emissions, and in addition involves less parts, it is desirable to retrofit a trailing arm assembly to a rear axle assembly of the three-wheeled vehicle by bringing technological and structural modifications to at least a portion of the trailing arm assembly for the vehicle so as to impart better aesthetic value, increase the performance of vehicle and further bring out vehicle with simple structure.
[00019] With the above objective in view, the present invention relates to the three-wheeled vehicle and, more particularly, to the electric three-wheeled vehicle operated by an electric power train assembly. As per one embodiment of the present invention, the electric three-wheeled vehicle comprises of a front wheel dirigibly supported by the frame and a pair of rear wheels carried by said frame. Further, the present invention describes a retrofittable trailing arm assembly with a modification in structure of the pair of trailing arms of the three-wheeled vehicle.
[00020] As per one embodiment of the present invention, the three-wheeled vehicle comprises the frame defining a vehicle longitudinal axis, the front wheel dirigibly supported by the frame and said pair of rear wheels carried by said frame. Referring to one embodiment of the present invention, the rear suspension system in the vehicle pivotally couples said pair of rear wheels to the frame. The rear suspension system comprises of the rear axle being operatively connected to said pair of rear wheels. Further, as per one embodiment of the present invention, the rear suspension system of the vehicle includes a trailing arm assembly for suspending the body of said vehicle with respect to said pair of rear wheels. As per one embodiment, said trailing arm assembly extends longitudinally from a front portion to a rear portion. In one embodiment, said trailing arm assembly is detachably secured to at least a portion of said rear axle of said rear suspension system. As per one embodiment, said trailing arm assembly is pivotally mounted to the frame through the front portion. Further, as per embodiment of the present invention, said rear portion of said trailing arm assembly comprises at least one mounting bracket configured and dimensioned for detachably securing said trailing arm to said at least a portion of the rear axle through at least one receiving bracket being fixedly attached to at least a portion of said rear axle. Furthermore, referring to one embodiment of the present invention, said trailing arm assembly comprises said pair of trailing arms including a first arm and a second arm. The first arm and the second arm are fixedly attached to the transverse pivot member at the front portion of the trailing arm assembly. Referring to one embodiment, said first arm and the second arm converge at said rear portion. The rear portion of said trailing arm assembly comprises said at least one mounting bracket and a hanger bracket being fixedly attached therein.
[00021] As per one embodiment of the present invention, a spring and shock absorber unit is operatively interposed between said trailing arm assembly and the frame and having one end mounted to said at least one mounting bracket including the hanger bracket. In one embodiment of the present invention, said at least one mounting bracket includes a C-shaped central portion and oppositely facing flanges extending outwardly from said C-shaped central portion. In one embodiment of the present invention, at least one gusset member is provided to said flanges of said at least one mounting bracket to provide structural support and stiffness to said at least one mounting bracket. As per one embodiment of the present invention said at least one mounting bracket, said hanger bracket and said at least one receiving bracket are made up of sheet metal.
[00022] Further, as per one embodiment, said rear suspension system comprises an electric power train assembly being integrally coupled to the rear axle for generating a drive torque and thereby transmitting said drive torque to said pair of rear wheels through said rear axle.
[00023] More specifically, the present invention relates to a dependent rear suspension system for the vehicle and more particularly to the dependent rear suspension including a retrofittable trailing arm assembly, as per one embodiment of the present invention. In one embodiment, the trailing arm assembly comprises a modified structure configured for detachably securing said trailing arm assembly to said at least a rear portion of the vehicle, thereby providing an ease of retrofitting said trailing arm assembly to the vehicle.
[00024] Accordingly, it is an object of the present invention to provide the electric three-wheeled vehicle with the dependent rear suspension system with modified trailing arm structure involving less number of parts, components and hence provide better performance and aesthetic value.
[00025] Further, it is another object of the present invention to provide the electric three-wheeled vehicle with the electric power train assembly integrally secured to the rear axle of the vehicle so as to provide a simple structure of the rear suspension system for the vehicle. As per one embodiment of the present invention, the electric power train assembly includes the electric drive motor and the gearbox.
[00026] Referring to one embodiment of the present invention, it is another object of the present invention to provide the electric three-wheeled vehicle with a simple contruction and light weight by providing improvement in said pair of trailing arm structure.
[00027] Further, recognizing the weight, range, performance, size, and cost challenges associated with the existing electric three-wheeled vehicle, the present invention provides an improvement in the electric three-wheeled vehicle that incorporates one or more of lightweight, advanced composite structures, dependent rear suspension and integrated electric power train assembly to the rear axle of the vehicle. In one embodiment, the electric power train assembly includes the electric drive motor and the gearbox.
[00028] It is advantageous to provide the dependent rear suspension system by retrofitting the rear axle with said electric power train and modifying the structure of said trailing arm assembly so as to impart simple structure to the vehicle and in addition maintaining the vehicle aesthetic value and increasing the efficiency and the performance.
[00029] Although the present invention has been exemplified for the three-wheeled vehicle, it is not restricted only for the three-wheeled vehicle. Application of the present invention may be extended to other vehicles, including four –wheeled vehicles.
[00030] Exemplary embodiments detailing features of the three-wheeled vehicle, in accordance with the present invention will be described hereunder. The embodiments described herein apply to an electric three-wheeled vehicle powered by a drive motor. However, the present invention is not restricted in its application and is also applicable to vehicles employing an internal combustion engine or either by an internal combustion engine or the drive motor selectively or by the drive motor alone.
[00031] The three wheeled automotive vehicle is mainly, but not solely, used as a passenger carrier. It is to be noted that “front” and “rear”, and “left” and “right” wherever referred to in the ensuing description, refer to front and rear, and left and right directions as seen in a state of being seated on a seat of the vehicle and looking forward. Furthermore, a longitudinal axis refers to a front to rear axis relative to the vehicle, while a lateral axis refers generally to a side to side, or left to right axis relative to the vehicle. Various other features of the three-wheeled vehicle according to the present subject matter here will be discernible from the following further description thereof, set out hereunder.
[00032] Further features and advantages of the invention, are described in detail below with reference to the accompanying drawings. In the drawings, like reference numbers generally indicate identical, functionally similar, and/or structurally similar elements. The drawing in which an element first appears is indicated by the leftmost digit(s) in the corresponding reference number.
[00033] Fig. 1. illustrates a side perspective view of an exemplary three-wheeled vehicle (10), in accordance with an embodiment of the present subject matter. The vehicle (10) has a frame (200) (shown in Fig.4), which includes a head tube (not shown), a main tube assembly extending rearward from the head tube. The vehicle (10) has a front cowl (13) positioned in the anterior portion of the head tube. A wind shield (12) is mounted to the front cowl (13). A floorboard (22) is extending from the bottom portion of the front cowl (13) to the rearward direction of the vehicle (10), supported by the main tube. A handle bar assembly (14) is rotatably supported by the head tube, positioned behind the front cowl (13). A front fender (15) is above the front wheel (16), covering at least a portion of the front wheel (16). A bottom portion of the cabin (21) constituting a passenger compartment is connected to the posterior portion of the floorboard (22). A pair of rear wheels (19) is connected to said pair of trailing arm (300) (shown in Fig.3 to Fig.7) through one or more suspension(s), and the front end of the trailing is in turn connected to the frame. The rear suspension system (400) (Fig.3) includes the spring (23) and the shock absorber (24) unit to the frame (200). A hydraulic braking system is attached to the front wheel (16) and said pair of rear wheel (19). A hood (11) connects a top portion of the front cowl (13) and a top portion of the body panel (20).
[00034] Further in Fig.1, as per one embodiment of the present invention, the vehicle (10) is longitudinally divided into two portions along the line X-X’; a front portion (F) has a driver’s seat (17) while a rear portion (R) of the vehicle has at least one passenger seat (18) with a seating capacity of one or more passengers. The driver seat (17) is positioned in a posterior portion to a handle bar assembly (14). A seat base and a backrest form the driver seat. The driver operates the vehicle (10) in a sitting position by sitting on the seat base. A partition wall is positioned along the line X-X’ extending in the lateral direction of the vehicle (10). The driver’s seat (17) comprises a seat base (17a) and a fixed backrest (17b).
[00035] Fig.2 is a perspective rear view of the three-wheeled vehicle (10) illustrating the electric power train assembly (101), (102) integrally mounted on rear axle (100) of the vehicle (10). As per one embodiment of the present invention, the vehicle (10) comprises of the front wheel (16) (shown in Fig.1) dirigibly supported by the frame (200) (shown in Fig.4) and said pair of rear wheels (19) carried by said frame. Referring to one embodiment of the present invention, said rear suspension system (400) (shown in Fig.3 to Fig.6) comprises of the rear axle (100) being operatively connected to said pair of rear wheels (19). As per one embodiment of the present invention, the hood (11) connects a top portion of the front cowl (13) (as shown in Fig.1) and a top portion of the body panel (20) and the bottom portion of the cabin (21) constituting the passenger compartment is connected to the posterior portion of the floorboard (22) (as shown in Fig.1). As per one embodiment of present invention, said electric power train assembly (101), (102) including the gearbox (101) and the electric drive motor (102) is integrally coupled to the rear axle (100) for generating a drive torque and thereby transmitting said drive torque to said pair of rear wheels (19) through said trailing arm assembly (300).
[00036] Fig. 3 is a perspective view of the rear suspension system (400) comprising of said pair of wheels (19), the rear axle (100), the electric power train assembly (101), (102), the spring (23) and the shock absorber (24) unit. As per one embodiment of the present invention said pair of rear wheels (19) is pivotally coupled to the frame (200) (shown in Fig.4) and the rear axle (100) being operatively connected to said pair of rear wheels (19). Referring to one embodiment of the present invention, said trailing arm assembly (300) is adapted for suspending the body of said vehicle (10) with respect to said pair of rear wheels (19) through the spring (23) and the shock absorber unit (24). As per one embodiment of the present invention, said trailing arm assembly (300) includes the pair of trailing arms (301a), (301b). In one embodiment, said pair of trailing arms (301a), (301b) includes a first arm (301a) and a second arm (301b) arranged to extend substantially longitudinally relative to the vehicle body in a laterally symmetrical relationship thereto, rotatably supporting a corresponding one of said pair of rear wheels (19). In one embodiment of the present invention, said trailing arm assembly (300) comprising said pair of trailing arms (301a), (301b) (shown in Fig. 5 to Fig.7) fixedly attached to the transverse pivot member (301) at the front portion (F’) and converges at said rear portion (R’).
[00037] Fig.4 illustrates a top view of the rear suspension system (400) with the said a trailing arm assembly (300). As per one embodiment of the present invention, the electric three-wheeled vehicle (10) comprises the frame (not shown) with at least a portion of a pair of side rails (201) laterally spaced by a rear frame member (200) along a vehicle transverse axis. The front portion (F’) of said pair of trailing arm (300) is mounted to said at least a portion of said rear frame member (200) through said transverse pivot member (301).
[00038] Further, in Fig.4, as per one embodiment of the present invention, said rear portion (R’) of said trailing arm assembly (300) is configured and dimensioned for detachably securing said trailing arm assembly (300) to said at least one receiving bracket (304) (shown in Fig.5 and Fig.6) being fixedly attached to said at least a portion of said rear axle (100).
[00039] Further in Fig.5, said electric power train assembly (101), (102) is integrally coupled to the rear axle (100) for generating a drive torque and thereby transmitting said drive torque to said pair of rear wheels (19) through said rear axle (100). Referring to one embodiment of the present invention, the electric power train assembly (101), (102) is integrally coupled to the rear axle (100) of the vehicle (10). With integration of said electric power train assembly (101), (102) including the gearbox (101) and the electric drive motor (102) with the rear axle (100) of the vehicle (10), an improved direct coupling of the transmission of the drive torque and to the rear axle (100) and said pair of real wheels (19) is achieved.
[00040] Fig.5 is a perspective view of the trailing arm assembly (300) detachably attached to at least a portion of said rear axle (100), as per one embodiment of the present invention. In one embodiment of the present invention, said trailing arm assembly (300) includes said pair of trailing arms (301a), (301b) including the first arm (301a) and the second arm (301b). Referring to one embodiment of the present invention, said pair of trailing arms (301a), (301b) including the first arm (301a) and the second arm (301a) is fixedly attached to a transverse pivot member (301) at the front portion (F’) and converges at said rear portion (R’) of the trailing arm assembly (300). As per one embodiment of the present invention, said rear portion (R’) of said trailing arm assembly (300) comprises the hanger bracket (302) and said at least one mounting bracket (303) (shown in Fig.5 and Fig.6) fixedly attached therein. Referring to one embodiment of the present invention, the spring (23) and shock absorber unit (24) is operatively interposed between said pair of trailing arm (300) and the frame (200) and having one end mounted to the hanger bracket (302). As per one embodiment of the present invention, the electric power train assembly (101), (102) is integrally coupled to the rear axle (100) of the rear suspension system (400) of the vehicle (10).
[00041] Fig. 6 is an exploded view of the trailing arm assembly (300) including said pair of trailing arm (301a), (301b), the transverse pivot member (301), said at least one mounting bracket (303) and said at least one hanger bracket (302). As per one embodiment of the present invention, said pair of trailing arm (301a), (301b) comprises the first arm (301a) and the second arm (301b). Referring to one embodiment of the present invention, the first arm (301a) and the second arm (301b) are fixedly attached to the transverse sectional member (301) at the front portion (F’) of said trailing arm assembly (300). Further, in one embodiment, the first arm (301a) and the second arm (301b) converges at said rear portion (R’) of said trailing arm assembly (300). In one embodiment of the present invention, said trailing arm assembly (300) including the front portion (F’) being pivotally mounted to the frame (200) and extending longitudinally to the rear portion (R’). The rear portion (R’) of said trailing arm assembly (300) comprising at least one mounting bracket (303) configured and dimensioned to be detachably secured to at least one receiving bracket (304) and the hanger bracket (302). In one embodiment, said at least one receiving bracket (304) is fixedly attached to said at least a portion of said rear axle (100). As per one embodiment, said hanger bracket (302) comprises of a supporting member (302a) and said at least one mounting member. (302b) and the supporting member (302a) are fixedly attached to the mounting member (302b). In one embodiment, the hanger bracket (302) is fixedly attached to the rear portion (R’) of said pair of trailing arm (300) through said at least one mounting member (302b).
[00042] Further in Fig 6, as per one embodiment of the present invention, the supporting member (302a) of the hanger bracket (302) comprises of at least one bolt hole for suspending the spring (23) and shock absorber (24) unit to the vehicle (10). Further, as per one embodiment of the present invention, the rear suspension system (400) comprises the electric power train assembly (101), (102) being integrally coupled to the rear axle (100) for generating a drive torque and thereby transmitting said drive torque to said pair of rear wheels (19) through said rear axle (200). In one embodiment, includes a gearbox (101), an electric motor (102), and a differential.
[00043] Fig.7 is a perspective exploded view of said trailing arm assembly (300) including said at least one mounting bracket (303) being fixedly attached to said rear portion (R’) thereof, as per one embodiment of the present invention. In one embodiment, said rear portion (R’) of said trailing arm assembly (300) comprises of the hanger bracket (302) and said at least one mounting bracket (303) fixedly attached therein. Further, referring to one embodiment of the present invention, said at least one mounting bracket (303) comprises of a C-shaped central portion (303a) configured to be secured to said at least a portion of said rear axle (100) and said oppositely facing flanges (303b) extending outwardly from said C-shaped central portion (303a). As per one embodiment of the present invention, said oppositely facing flanges (303b) comprises of said at least one gusset member (303c) providing structural support and stiffness to said at least one mounting bracket (303), thereby preventing said at least one mounting bracket (303) from bending under load conditions. In one embodiment of the present invention, said at least one mounting bracket (303) and said hanger bracket (302) is made up of sheet metal.
[00044] Advantageously, as per one embodiment of the present invention the retrofittable rear suspension system with modification in the structure of said pair of the trailing arm, integrated electric power train assembly to the rear axle and the dependent rear suspension provides simple structure to the electric three-wheeled vehicle. Further, as per one embodiment of the present invention, the electric three-wheeled vehicle involves less number of components and parts as compared to conventional petrol-diesel three-wheeled vehicle and hence provide environmentally friendly, energy efficient and cost effective transport system.
[00045] Improvements and modifications may be incorporated herein without deviating from the scope of the invention.
,CLAIMS:We claim:
1. A vehicle (10) comprising:
a frame (200) defining a vehicle longitudinal axis (AA);
one or more front wheels (16) and a pair of rear wheels (19) supported by the frame (200);
a rear suspension system (400) pivotally coupling said pair of rear wheels (19) to the frame (200), said rear suspension system (400) including a rear axle (100) being operatively connected to said pair of rear wheels (19); and
a trailing arm assembly (300) including a pair of trailing arms (301a), (301b) for suspending a body of said vehicle (10); wherein said trailing arm assembly (300) is detachably secured to at least a portion of said rear axle (100) of said rear suspension system (400).
2. The vehicle (10) as claimed in claim 1, wherein said rear portion (R’) of said trailing arm assembly (300) comprises at least one mounting bracket (303) configured for detachably securing said trailing arm assembly (300) to at least one receiving bracket (304) being fixedly attached to at least a portion of said rear axle (100).
3. The vehicle (10) as claimed in claim 1, wherein said pair of trailing arms (301a), (301b) includes a first arm (301a) and a second arm (301b).
4. The three-wheeled vehicle (10) as claimed in claim 3, wherein said first arm (301a) and the second arm (301a) of said pair of trailing arms (301a), (301b) are fixedly attached to a transverse pivot member (301) at the front portion (F’) of said trailing arm assembly (300).
5. The vehicle (10) as claimed in claim 1, wherein said pair of trailing arms (301a), (301b) comprising said first arm (301a) and the second arm (301a) converges at said rear portion (R’) of said trailing arm assembly (300).
6. The vehicle (10) as claimed in claim 1, wherein said rear portion (R’) of said trailing arm assembly (300) comprises a hanger bracket (302) fixedly attached to at least a portion thereof.
7. The vehicle (10) as claimed in claim 6, wherein said hanger bracket (302) comprises a supporting member (302a) and at least one mounting member (302b) fixedly attached to the supporting member (302a).
8. The vehicle (10) as claimed in claim 7, wherein a spring (23) and shock absorber unit (24) is operatively interposed between said trailing arm assembly (300) and the frame (200) and having one end mounted to the hanger bracket (302).
9. The vehicle (10) as claimed in claim 1, wherein said at least one mounting bracket (303) comprises a C-shaped central portion (303a) and oppositely facing flanges (303b) extending outwardly from said C-shaped central portion (303a).
10. The vehicle (10) as claimed in claim 1, wherein an electric power train assembly (101), (102) integrally coupled to the rear axle (100) is adapted for generating a drive torque and thereby transmitting said drive torque to said pair of rear wheels (19) through said rear axle (100).