DESC:TECHNICAL FIELD
[0001] The present subject matter relates generally to a monocoque structure for a motor vehicle and more particularly to a steering support assembly for the monocoque structures.
BACKGROUND
[0002] Generally, a two-wheeled vehicle has a frame structure, or a monocoque structure that acts as a structural member and bears the load of the vehicle. Typically, a tubular section or castings form the frame structure, which acts as structural member, for bearing loads and for mounting vehicle parts. In addition, plurality of panels covers the frame structure of the vehicle. Whereas, in a monocoque structure, the monocoque structure itself is an integral part of the body, which acts as the structural member that constitutes of mountings for vehicle parts and also acts as body of the vehicle.
BRIEF DESCRIPTION OF DRAWINGS
[0003] The detailed description of the present subject matter is described with reference to the accompanying figures. Same numbers are used throughout the drawings to reference like features and components.
[0004] Fig. 1 illustrates a left side view of an exemplary vehicle 100, in accordance with an embodiment of present subject matter.
[0005] Fig. 2 (a) illustrates a left side perspective view of a monocoque structure 200, in accordance with an embodiment of the present subject matter.
[0006] Fig. 2 (b) depicts a top view of the monocoque structure 200.
[0007] Fig. 3 (a) illustrates a front view of a monocoque structure 201, in accordance with another embodiment of the present subject matter.
[0008] Fig. 3 (b) depicts across-sectional view of the monocoque structure 201.
[0009] Fig. 3 (c) illustrates another cross-sectional view of the monocoque structure 201.
[00010] Fig. 3 (d) depicts an exploded view of the monocoque structure 201.
DETAILED DESCRIPTION
[00011] Generally, in a monocoque structure, a pair of side railings are disposed at extreme lateral ends, is known in the art. The side railing(s) are formed by plurality of sub-railings. The sub-railings are made of a rigid material. Further, the monocoque structure includes one or more bridge members that are connecting the pair side of railings and are disposed therebetween. In addition, the monocoque structure supports a front wheel and a rear wheel of the vehicle.
[00012] Typically, the front wheel and the rear wheel are subjected to various forces from road surfaces and loads acting on vehicle. Moreover, the front wheel is a part of a steering assembly, which is used to steer the vehicle. The steering assembly is also supported by the monocoque structure. The forces and loads acting on the front wheel are received by a steering shaft of the steering assembly. In addition, the monocoque structure is subjected to the forces and loads acting on the steering assembly.
[00013] Conventionally, a steering tube, which supports the steering assembly, is known in the art. For the steering assembly to with stand the forces and loads, the steering tube is to be reinforced. This would increase the weight of the monocoque structure. Also, integration of steering tube with the monocoque structure is complex. In addition, the forces and loads acting on the steering tube of the monocoque structure would result in deforming the monocoque structure.
[00014] Thus, there is need for providing structural member that is capable of supporting the steering assembly. However, the structural member should be capable of receiving the forces or loads received from the wheel. In addition, the structural member is to be provided without increasing weight of the system.
[00015] The present subject matter is aimed at addressing the aforementioned and other problems in the prior art. Hence, it is an object of the present subject matter to provide a monocoque structure. The monocoque structure is provided with a steering support assembly disposed in a front portion of the monocoque strucutre. According to an aspect, the monocoque structure is capable of supporting steering assembly of the vehicle. According to another aspect, the monocoque structure enables load distribution received from the wheel. Further, the support assembly provides monocoque structure with less weight. In addition, the monocoque structure provides structural rigidity with less weight thereby improving performance of the vehicle.
[00016] It is an advantage that the steering support assembly provides a lightweight yet a rigid steering supporting structure. It is another advantage that the need for tube is reduced/eliminated as the steering support assembly is composed of lightweight sheet metal or fiber reinforced plastic.
[00017] It is another advantage that the weight of the steering support assembly is reduced. Also, the weight of the overall vehicles is also reduced, thereby improving performance of the vehicle.
[00018] Additional advantage being, the monocoque structure provided with the steering support assembly enables improved load distribution by the steering support assembly whereby deformation of monocoque structure is reduced due to improved load distribution.
[00019] In an embodiment, a monocoque structure is provided. The monocoque structure is employed with a steering support assembly. The monocoque structure includes a pair of railings disposed at vehicle width end(s). Further, one or more bridge member(s) are connecting the pair of railings and disposed therebetween. The bridge members are adapted to rotatably support a steering assembly. Further, a support member encloses at least a portion of the steering shaft and the support member is abuttingly disposed to at least one of said bridge member(s), and said side railing(s). The monocoque further comprises a leg shield connecting the pair of railings and supporting the bridges. Furthermore, the leg shield abuttingly supports at least a portion of the bridge members.
[00020] In one embodiment, the support member of the monocoque structure includes a central member that encloses a circumference of a steering shaft of the steering assembly and enables load bearing. In an embodiment, the central member encloses said steering shaft circumference by 70 percent.
[00021] In an embodiment, the central member of the steering shaft is substantially disposed forwardly of the steering shaft. In another embodiment, the steering shaft is substantially disposed rearwardly of the steering shaft. In yet another embodiment, the support member is obliquely disposed and a central member is disposed enclosing at least a portion of the steering shaft that enables load bearing of the bridge members that are subject to forces acting on the steering assembly.
[00022] In an embodiment, the support member of the monocoque structure includes a pair of arms that are connected to the central member, and the arms are abuttingly disposed to at least one of said bridge member(s) and said side railing(s). Further, the arms includes one or more deck members that are integrally formed with the arms thereby providing structural rigidity.
[00023] The monocoque structure is made of a rigid material including sheet metal.
[00024] The aforesaid and other advantages of the present subject matter would be described in detail in conjunction with the figures in the following description.
[00025] Fig. 1 illustrates an exemplary step-through type vehicle with a monocoque structure, in accordance with an embodiment of the present subject matter. The vehicle 100 has a monocoque structure 200 that acts as structural member and load bearing member of the vehicle 100. A handlebar assembly 105 is rotatably connected to a front wheel 110 through the monocoque structure 200 at a front portion F. The monocoque structure extends from a front portion F towards a rear portion R, which is along the longitudinal direction F-R of the vehicle 100. The vehicle width extends in right side RS and left side LS, which is in the lateral direction RS-LS. One or more front fork(s) 115 connect the front wheel 110 to the handlebar assembly 105. An engine assembly 120is swingably connected to the monocoque structure 200. Further, the engine assembly 120 is functionally connected to a rear wheel 125 through a transmission assembly (not shown). The transmission assembly includes an automatic transmission, or a variable transmission system, or manual transmission system. The rear wheel 125 is rotatably connected to the transmission system and one or more rear suspension(s) 130 provided todampen forces acting on the rear wheel 125 from reaching monocoque structure 200. In another embodiment (not shown), a swing arm supports the rear wheel and the swing arm is swingably connected to the monocoque structure. A seat assembly 135 is positioned above engine assembly 120 and the seat assembly 135 in an open condition provides access to a utility box (not shown) disposed below the seat assembly 135. A pillion handle140 is provided on the rear portion R of the vehicle 100.
[00026] A front fender 145 is provided at the front portion for covering at least a portion of the front wheel 110. A rear fender 150 is covering at least a portion of the rear wheel 125. Further, the vehicle 100 comprises of plurality of electrical/electronic components including a headlight 155 that is disposed in proximity to the handle bar assembly 105, a tail lamp 160 that is disposed rearwardly of the seat assembly 135, a battery (not shown), a transistor controlled ignition (TCI) unit (not shown), an alternator (not shown), and a starter motor (not shown). A front panel 165 acts as a windshield for deflecting. In an embodiment, an electric motor (not shown) is hub mounted to the rear wheel 125. The engine assembly 120 and the hub motor act as power unit for the vehicle 100.
[00027] Fig. 2 (a) illustrates a front perspective view of the monocoque structure 200, in accordance with an embodiment of the present subject matter. The monocoque structure 200 includes a pair of railings 205A;205B disposed at vehicle width ends RS-LS of the vehicle 100. Further, the monocoque structure 200 includes one or more bridges 220, 305 (shown in Fig. 2 (b)) that are connecting the pair of railings 205A, 205B. In the present embodiment, the pair of railings 205A, 205B includes a right side railing 205A and a left side railing 205B that extend from below a handle bar assembly 105 (shown in Fig. 1) towards a step-through portion SP of the vehicle. In one embodiment, the pair of railings 205A, 205B extends from below the handle bar assembly 105 towards a rear portion of the vehicle 100. A floorboard 215 is disposed at the step-through portion SP that is supported by the pair of railings 205A, 205B, and bridge members 220. Furthermore, a leg shield 210 is disposed in an anterior portion of the step-through portion SP and is connecting the pair of railings 205A, 205B. The monocoque structure 200 is provided with a steering support assembly 300, disposed in a front portion of the monocoque structure 200, which supports a steering assembly including a steering shaft 170.
[00028] In an embodiment, the railing(s) are formed by plurality of sub-railings. The sub-railings extend from step-through portion towards a rear portion of the vehicle in an inclined manner. Further, a housing assembly is disposed to the pair of railings and positioned rearwardly of the step-through space.
[00029] Fig. 2 (b) depicts a top view of the monocoque structure 200 employed with the steering support assembly 300.The steering support assembly 300 includes one or more bridges 305 that are disposed between the pair of railings 205A, 205B and supported by at least a portion of said pair of railings 205A, 205B. The bridge member305is adapted to pivotally support a steering shaft 170 of a steering assembly (not shown) of the vehicle, wherein the steering assembly includes a steering shaft 170. Further, the leg shield 210supports the bridge members 305 by supporting the steering assembly 300 in a posterior portion. Furthermore, at least one support member 310 is disposed substantially extending along the lateral direction RS-LSof the vehicle, which is along vehicle width direction RS-LS. The support member 310 encloses at least a portion of the steering shaft 170. In a preferred embodiment, the support member 310 annularly encloses at least a circumference of the steering shaft 170.
[00030] Fig. 3 (a) depicts a front view of a monocoque structure 201, in accordance with another embodiment of the present subject matter.Themonocoque structure 201 includes a pair of railings 205A, 205B that are disposed at vehicle width end(s) of the vehicle RS-LS. The monocoque structure in the present embodiment includes one or more bridge members 405A, 405B that are disposed in the front portion of the monocoque structure 201, which is below the handle bar assembly 105 (shown in Fig. 1) and forwardly upward of the floorboard 215. The bridge members 405A, 405B includes a first bridge member 405A and a second bridge member 405B. Further, a support member 410 is disposed substantially in vehicle width direction connecting the pair of railings 205A, 205B. In another embodiment, the support member 410 is abuttingly disposed to at least one of said bridge member(s) 405A, 405B, and said side railing(s) 205A, 205B.
[00031] The first bridge member 405A is provided with a aperture provision 405AA for rotatably supporting the steering shaft 170. The second bridge member 405B is provided with another aperture provision 405BA that rotatably supports the steering shaft 170. Further, each aperture provision 405AA, 405BAis adapted to support a bearing assembly (not shown) that enable rotation of a lower bracket (not shown) and an upper bracket (not shown) of the steering assembly of the vehicle. The monocoque structure 200 further comprises a support member that is adapted to support the steering shaft 170.
[00032] In the present embodiment, the first bridge member 405A is connected to the support member 410 and the leg shield 210. The second bridge member 405B is connected the pair of railings 205A, 205B and is disposed therebetween. The provision(s) 405AA, 405BA provided on said bridge member(s) 405A, 405B are disposed with a vertical offset in the longitudinal direction F-R to provide caster angle for the steering assembly. The support member 410 comprises of central member 410C that encloses at least a portion of the steering shaft 170and the central member 410C enables load bearing from the bridge members 405A, 405B. The central member 410C is disposed enclosing the steering shaft 170 circumferentially. In an embodiment, the central member 410Cannularly encloses the steering shaft 170 circumference by 70percentage. Further, the support member 410 includes a pair of arms 410A, 410B (shown in Fig. 3 (b)) that are connected to the central member 410. The pair of arms 410A, 410B is integrally formed with the central member 410C and the pair of arms 410A, 410B connects the central member 410 to pair of railings 405A, 405B. In other words, the support member 410 is abuttingly disposed to at least one of said bridge member(s) 410A, 410B, and said side railing(s) 205A, 205B.
[00033] In one embodiment, the support member 410 includes at least an extended portion 410AE, 410BE extending beyond a position or height of the bridge member 405A, wherein the at least an extended portion 410AE, 410BE provides additional support to the steering support assembly 400. This extended portion 410AE, 410BE is connecting to the right side railing 205A and the left side railing 205B thereby providing structural support to the steering support assembly 400.
[00034] Fig. 3 (b) depicts a cross-sectional view of the monocoque structure 201 taken along axis X-X’. The first bridge member 405A is supported by the arms 410A, 410B of the support member 410. Also, the leg shield 210 supports a rear surface of the first bridge member 405A. Load from steering assembly is supported by the first bracket 405A, the support member 410, which in turn shared by the pair railings 205A, 205B that area connected to said support member 410.
[00035] Fig. 3 (c) depicts another cross-sectional view of the monocoque structure 201 taken along axis Y-Y’. The second bridge 405B is connecting the pair of railings 205A, 205B. The second bridge 405B is connected to the support member 410. In the present embodiment, each arm of the arms 410A, 410B is provided with one or more deck members 410AA, 410BA that provide structural rigidity to the steering support assembly and are integrally formed. The arms 410A, 410B further comprises of stiffener end(s) that are extending substantially along longitudinal direction F-R of the vehicle. The stiffener members are connected to the pair of railings 205A, 205B and provide additional structural rigidity. In addition, the central member 410C is inclinedly disposed, which is at caster angle, to work in conjunction with the first bridge 405A and the second bridge 405B. Further, the support member 410 is disposed forwardly of the steering shaft. In another embodiment, the support member is disposed rearwardly of the steering shaft and the central member enclosing at least a portion of the steering shaft and bearing load acting on the bridge members 405A, 405B.
[00036] Fig. 3 (d) depicts an exploded view of the steering support assembly 400 of the monocoque structure 201, in accordance with the embodiment depicted in Fig. 3 (a). The pair of railings 205A, 205B is disposed at vehicle width RS-LS end(s), wherein the pair of railings includes a right side railing 205A, and a left side railing 205B. Further, one or more bridge member(s) 405A, 405Bare disposed between the right side railing 405A and the left side railing 405B. The bridge members 405A, 405B includes a first bridge member 405A and a second bridge member 405B adapted to rotatably support a steering assembly. Further, a support member 410 encloses at least a portion of the steering shaft 170 and the support member 410 is abuttingly disposed to at least one of said bridge member(s) 405A, 405B, and said side railing(s) 205A, 205B. In addition, the leg shield 210 is connecting the pair of railings 205A, 205B and supporting the bridges 405A, 405B.
[00037] In one embodiment, the support member 410 includes L-shaped lateral ends. The L-shaped lateral ends provide improved contract area with the right side railing 205A and the left side railing 205B and provide structural strength to the support member 410. Also, the support member 410 is provided with plurality of elongated holes420A, 420B, 420C, 420D, wherein the elongated holes 420A, 420B, 420C, 420D enable reduction of weight and at the same time retains the structural strength of the support member 410.
[00038] Also, the steering support assembly in an assembled condition provides a closed structure. The side railings in width direction, the bridge member in vertical direction and the support member and the leg shield in horizontal/ longitudinal direction result a closed structure that provides rigid structure to support the steering assembly including steering shaft. Additionally, the steering assembly is preferably made of rigid material including sheet metal or fiber reinforced plastic that provides a lightweight steering support assembly.
[00039] In the present embodiment, the monocoque structure along with the steering support assembly is made of a sheet metal and that one or more parts are secured by welding forming the monocoque structure employed with steering support structure.
[00040] In one embodiment, the monocoque structure is made of a rigid material including polymers or composite materials.
[00041] It is to be understood that the aspects of the embodiments are not necessarily limited to the features described herein. Many modifications and variations of the present subject matter are possible in the light of above disclosure. Therefore, within the scope of claims of the present subject matter, the present disclosure may be practiced other than as specifically described. ,CLAIMS:I/We claim:
1. A monocoque structure (200, 201) for a two-wheeled vehicle (100), said monocoque structure (200, 201) comprising:
a right side railing (205A), and a left side railing (205B) disposed substantially at vehicle width end(s) (RS-LS), said right side railing (205A) and said left side railing (205B) extend from below a handle bar assembly (105) towards a step-through portion (SP) defined by said monocoque structure (200); and
one or more bridge member(s) (220, 305, 405A, 405B) connecting said right side railing (205A) and said left side railing (205B), and disposed therebetween,
wherein
a steering support assembly (300, 400) capable of rotatably supporting a steering shaft (170) disposed in front portion of said monocoque structure (200), said steering support assembly(300, 400) includes at least one bridge member (305, 405A, 405B) of said one or more bridge members (220, 305, 405A, 405B), and at least one support member (310, 410),
said at least one bridge member (305, 405A, 405B) is adapted to support said steering support assembly (300, 400), and said at least one support member (310, 410) extending in vehicle width direction (RS-LS) connected to said right side railing (205A) and said right side railing (205B), and said at least one support member (310, 410) annularly encloses at least a portion of said steering shaft (170).
2. The monocoque structure (201) as claimed in claim 1, wherein said at least one bridge member (405A, 405B) includes a first bridge member (405A) and a second bridge member (405B) vertically spaced, and said at least one support member (410) is connected to said first bridge member (405A) and said second bridge member (405B).
3. The monocoque structure (201) as claimed in claim 1, wherein said support member (410) includes a central member (410C) annularly enclosing at least a portion of said steering shaft (170), wherein said central member (410C) annularly enclosed at least 70 % of circumference of said steering shaft (170).
4. The monocoque structure (201) as claimed in claims 1 or 3, wherein said support member (410) includes a pair of arms (410A, 410B) disposed on either sides of said central member (410C), and said pair of arms (410A, 410B) are connected to at least one of said at least one bridge member (305, 405A, 405B), said left side railing (205A), and said right side railing (205B).
5. The monocoque structure (201) as claimed in claim 4, wherein said pair of arms (410A, 410B) includes at least a portion (410AE, 410BE) extending beyond the height of said at least one bridge member (405A) to provide additional support to said steering support assembly (400).
6. The monocoque structure (201)as claimed in claim 1, wherein said support member (410) includes one or more deck members (410AA, 410BA) integrally formed with said support member (410), wherein said deck members (410AA, 410BA) includes angular protrusion.
7. The monocoque structure (200, 201) as claimed in claim 1, wherein said monocoque structure (200, 201) comprises a leg shield (210) disposed at anterior portion at the step-through portion (SP), and said leg shield (210) is connected to said right side railing (205A) and said left side railing (205B).
8. The monocoque structure (200, 201) as claimed in claims 1 or 6, wherein said leg shield (210) supports at least a portion of said at least one bridge member (305, 405A, 405B).
9. The monocoque structure (200, 201) as claimed in claim 1, wherein said at least one bridge member (305, 405A, 405B)includes aperture provisions (405AA, 405BA) and capable of supporting a bearing assembly for rotatably supporting the steering shaft (170).
10. The monocoque structure (200, 201) as claimed in claim 1, wherein said monocoque structure (200, 201) is composed of a rigid material including sheet metal, or fiber reinforced plastic.