Claims:WE CLAIM:
1. A frame assembly (200) for a two-wheeled vehicle (100), the frame assembly (200) comprising:
a front frame structure (210), the front frame structure (210) comprising a pair of upper tubes (212l,r) and a pair of down tubes (214l,214r);
an engine mounting bracket (220) joined to and extending downwards from the pair of upper tubes (212l,r) and the pair of down tubes (214l,r); and
a reinforcing structure (250), the reinforcing structure (250) comprising a substantially U-shaped reinforcing member (230) and a pair of side tubes (222) joined to the reinforcing member (230), a pair of seat rails (290) of the vehicle (100) being joined to a rear portion of the reinforcing structure (250).

2. The frame assembly (200) as claimed in claim 1, wherein the reinforcing member (230) has a pair of reinforcing tubes (230l,r) extending downwards from a centre tube (232) portion of the reinforcing member (230) to form the substantially U-shaped reinforcing member (230), the pair of reinforcing tubes (230l,r) being joined to the pair of upper tubes (212l,r) and the pair of down tubes (214l,214r).
3. The frame assembly (200) as claimed in claim 2, wherein each of the pair of reinforcing tubes (230l,r) joins to each of the respective pair of upper tubes (212l,r) at respective junction points (230lj and 230rj), the junction points (230lj and 230rj) being substantially in the middle along the length of reinforcing tubes (230l,r), each of the pair of reinforcing tubes (230l,r) further extending downwards beyond the junction points (230lj and 230rj) to join to each of the respective pair of down tubes (214l,r).

4. The frame assembly (200) as claimed in claim 3, wherein the pair of side tubes (222) includes a left tube (222l) and a right tube (222r), each of the pair of side tubes (222) is joined to the reinforcing member (230) at a substantially centre portion (232c) of the centre tube (232) at first tube ends (222r-f and 222l-f) of the pair of side tubes (222), each of the pair of side tubes (222) extending outwards and downwards from the centre portion (232c) and being joined to the pair of upper tubes (212l,r) at second tube ends (222r-s and 222l-s) of the pair of side tubes (222).

5. The frame assembly (200) as claimed in claim 4, wherein the pair of seat rails (290) is directly mounted on and joined to the reinforcing member (230).

6. The frame assembly (200) as claimed in claim 5, wherein the reinforcing structure (250) has a pair of seat rail mounting means (292l,r) for mounting the pair of seat rails (290), the pair of seat rail mounting means (292l,r) being mounted on the reinforcement member (230), each of the pair of seat rails (290) being directly mounted on the reinforcing member (230) through the respective pair of seat rail mounting means (292l,r).

7. The frame assembly (200) as claimed in claim 6, wherein the pair of seat rail mounting means (292l,r) is mounted on the reinforcing member (230) near end portions (232l,r) of the centre tube member (232) and extends downward from each of the end portions (232l,r), the pair of seat rails (290) being joined to the mounting means (292) at a location vertically below the centre portion (232c) of the reinforcing member (230).

8. The frame assembly (200) as claimed in claim 7, wherein a rear shock absorber of the vehicle (200) is directly mounted on the reinforcing structure (250).

9. The frame assembly (200) as claimed in claim 8, wherein the rear shock absorber is mounted through a shock absorber mounting bracket (240), the shock absorber mounting bracket (240) being joined on substantially the centre portion (232c) of the centre tube (232).

Dated this 31st day of March 2022
TVS MOTOR COMPANY LIMITED
By their Agent & Attorney

(Nikhil Ranjan)
of Khaitan & Co
Reg No IN/PA-1471 , Description:FORM 2
THE PATENTS ACT, 1970
(39 OF 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
[See section 10, Rule 13]

TITLE OF INVENTION
A Frame Assembly for a Vehicle

APPLICANT
TVS MOTOR COMPANY LIMITED, an Indian company, having its address at “Chaitanya”, No.12 Khader Nawaz Khan Road, Nungambakkam, Chennai 600 006, Tamil Nadu, India.

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

FIELD OF THE INVENTION
[001] The present invention relates to a frame assembly of a vehicle and more particularly to a frame assembly for a two-wheeled vehicle.

BACKGROUND OF THE INVENTION
[002] A frame structure in a two-wheeled vehicle is the skeletal support structure of the vehicle. Typically, the frame structure is a frame assembly of a head tube, a pair of down tubes, a main tube, and a pair of seat rails which extends towards a rear end of the vehicle. The main tube extends rearwardly from the head tube rearwardly from the head tube. The main tube has a pair of upper tubes, which are extending rearwardly downwardly from the head tube and further extends to support an engine using an engine mounting bracket. The seat rails are welded to either sides of the upper frame tubes and extend in vehicle rearward direction to support the seat of the vehicle. The headtube forms a castor angle for the vehicle.
[003] In one frame construction in a known art for conventional commuter motorcycles, a mono main tube is permanently connected with a frame head tube. The main tube is used for withstanding and transferring the loads borne by the vehicle during driving. The pair of down tubes on the left and the right side of the vehicle running parallelly downwards from the main tube are connected permanently on either sides of the main tube. The down tubes also support and share some weight of the engine mounted on the main tube through the engine mounting brackets.
[004] Conventionally, a bridge tube welded to the head tube and the main tube near a joint between the head tube and the main tube, is provided which increases the torsional strength of the frame. A fuel tank is disposed on the top of the main tube. A shock absorber mounting bracket is mounted to a portion of the main tube, such that a top portion of the shock absorber is mounted to the main tube and the end portion is mounted to a swing arm.
[005] It is apparent with the advancing technology, there has been an increased requirement of vehicular elements and packaging of various vehicle operating elements. As a result, effective utilisation of the limited space in the vehicle is crucial.
[006] In another known art, the lower end portion of the shock absorber is attached to a bracket welded to a cross member joining the left and right swing arm in front of the rear wheel through linkage mechanism. The upper end portion of the shock absorber is supported by a bracket connected to the main tube. The bracket is secured to a cross pipe disposed bridge wise between the pair of left and right seat rails.
[007] In the frame constructions as elucidated in the above para, the pair of seat rails are formed and welded to the frame structure. Due to manufacturing variations, the tubes are subjected to revising and lot of welding distortions happen at the main frame bending area. This further weakens sections connecting the shock absorber. Hence, under load bearing conditions, the main frame junction becomes weak and subject to crack and is prone to failure.
[008] In another construction in a known art for conventional two-wheeled vehicle frame assembly, a rear frame structure is joined to a front frame structure at mounting points to form a main frame. A shock absorber is mounted on a bracket provided on a reinforcing member. The reinforcing member is, in turn, mounted on the main frame.
[009] However, the above-mentioned configuration consumes a lot of space in the vehicle. As a result of which a compromise has to be made with respect to the size and volume available for other components in the vehicle. Further, the structure of the frame in the conventional arts provides a seat assembly of the vehicle at an increased height which requires additional effort from the rider to mount the vehicle.
[010] Further, in conventional frame designs, a portion of an upper tube of seat rails is required to be bent to accommodate the shock absorber. However, the bend is undesirable as it reduces the structural rigidity of the frame.
[011] Thus, there is a need in the art for a frame structure for a vehicle, which addresses at least some of the aforementioned problems.

SUMMARY OF THE INVENTION
[012] In one aspect, the present invention is directed at a frame assembly for a two-wheeled vehicle. The frame assembly includes a front frame structure, an engine mounting bracket, and a reinforcing structure. The front frame structure includes a pair of upper tubes and a pair of down tubes. The engine mounting bracket is joined to and extends downwards from the pair of upper tubes and the pair of down tubes. The reinforcing structure includes a substantially U-shaped reinforcing member and a pair of side tubes joined to the reinforcing member. A pair of seat rails of the vehicle is joined to a rear portion of the reinforcing structure.
[013] In an embodiment, the reinforcing member has a pair of reinforcing tubes extending downwards from a centre tube portion of the reinforcing member to form the substantially U-shaped reinforcing member. The pair of reinforcing tubes is joined to the pair of upper tubes and the pair of down tubes.
[014] In an embodiment, each of the pair of reinforcing tubes joins to each of the respective pair of upper tubes at respective junction points, which are substantially in the middle along the length of reinforcing tubes. Each of the pair of reinforcing tubes further extends downwards beyond the junction points to join to each of the respective pair of down tubes.
[015] In an embodiment, the pair of side tubes includes a left tube and a right tube. Each of the pair of side tubes is joined to the reinforcing member at a substantially centre portion of the centre tube at first tube ends of the pair of side tubes. Each of the pair of side tubes extends outwards and downwards from the centre portion and is joined to the pair of upper tubes at second tube ends of the pair of side tubes.
[016] In an embodiment, the pair of seat rails is directly mounted on and joined to the reinforcing member. The reinforcing structure has a pair of seat rail mounting means for mounting the pair of seat rails. The pair of seat rail mounting means is mounted on the reinforcing member. Each of the pair of seat rails is directly mounted on the reinforcing member through the respective pair of seat rail mounting means.
[017] In an embodiment, the pair of seat rail mounting means is mounted on the reinforcing member near end portions of the centre tube member and extends downward from each of the end portions. The pair of seat rails is joined to the mounting means at a location vertically below the centre portion of the reinforcing member.
[018] In an embodiment, a rear shock absorber of the vehicle is directly mounted on the reinforcing structure. The rear shock absorber is mounted through a shock absorber mounting bracket, which is joined on substantially the centre portion of the centre tube.

BRIEF DESCRIPTION OF THE DRAWINGS
[019] Reference will be made to embodiments of the invention, examples of which may be illustrated in accompanying figures. These figures are intended to be illustrative, not limiting. Although the invention is generally described in context of these embodiments, it should be understood that it is not intended to limit the scope of the invention to these particular embodiments.
Figure 1 illustrates a two-wheeled vehicle in a left side view, in accordance with an embodiment of the invention.
Figures 2A-C illustrate a frame assembly in various views including a left side view and a perspective view, in accordance with various embodiments of the invention, wherein,
Figure 2A illustrates a portion of the frame assembly in a perspective view, in an embodiment of the invention;
Figure 2B illustrates the frame assembly in a left side view view, in an embodiment of the invention; and
Figure 2C illustrates the frame assembly in a rear perspective view in accordance with an embodiment of the invention.
Figures 3A-C illustrate a reinforcing structure of the frame assembly in various views, in accordance with various embodiments of the invention, wherein,
Figure 3A illustrates an exploded view of the reinforcing structure, in accordance with an embodiment of the invention;
Figure 3B illustrates a perspective view of the reinforcing structure in an assembled condition, in accordance with an embodiment of the invention; and
Figure 3C illustrates a part of the reinforcing structure in a left side view, in accordance with an embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION
[020] The present invention relates to a frame assembly for a vehicle and more particularly to a frame assembly for a two-wheeled vehicle.
[021] Figure 1 illustrates a two- wheeled vehicle 100, in accordance with an embodiment of the invention. As an example, the vehicle 100 is a two-wheeled motorcycle. The vehicle 100 comprises a prime mover 110 that is adapted to provide motive force for movement of the vehicle 100. In an embodiment, the prime mover 110 is an internal combustion engine, which is preferably a single-cylinder engine. In another embodiment, the prime mover 110 is an electric motor. The vehicle 100 comprises a front wheel 112, a rear wheel 108, a frame assembly 200 (shown and explained in greater details with reference to later figures). A seat assembly (120) is configured to be mounted on the frame assembly (200) in a rear portion of the vehicle 100.
[022] Figures 2A-C illustrate the frame assembly 200 in various views in accordance with various embodiments of the invention. Figure 2A illustrates a portion of the frame assembly 200 in a perspective view, in an embodiment of the invention. Figure 2B illustrates the frame assembly 200 in a left side view, in an embodiment of the invention. Figure 2C illustrates the frame assembly 200 in a rear perspective view in accordance with an embodiment of the invention. The frame assembly 200 includes a front frame structure 210, an engine mounting bracket 220, and a reinforcing structure 250. The front frame structure 210 includes a pair of upper tubes (212l,r) extending rearwardly from a head tube (216) and a pair of down tubes (214l,214r) extending rearwardly downwardly from the head tube (216). The pair of upper tubes (212l,r) and the pair of down tubes (214l,r) are narrow near the head tube (216) and are tapering outwards towards the rear portion of the vehicle (100). The engine mounting bracket 220 is joined to and extends downwards towards a ground level from the pair of upper tubes (212l,r) and the pair of down tubes (214l,r), and is configured to mount the power unit of the vehicle. The reinforcing structure 250 includes a substantially U-shaped reinforcing member 230 and a pair of side tubes 222 joined to the reinforcing member 230. A pair of seat rails 290 of the vehicle 100 is joined to a rear portion of the reinforcing structure 250.
[023] Figures 3A-C illustrate the reinforcing structure 250 of the frame assembly 200 in various views, in accordance with various embodiments of the invention. Figure 3A illustrates an exploded view of the reinforcing structure 250, in accordance with an embodiment of the invention. Figure 3B illustrates a perspective view of the reinforcing structure 250 in an assembled condition, in accordance with an embodiment of the invention. Figure 3C illustrates a part of the reinforcing structure 250 in a left side view, in accordance with an embodiment of the invention. The reinforcing member 230 has a pair of reinforcing tubes (230l,r) extending downwards from a centre tube 232 of the reinforcing member 230 to form the substantially U-shaped reinforcing member 230. The pair of reinforcing tubes (230l,r) is joined to the pair of upper tubes (212l,r) and the pair of down tubes (214l,214r).
[024] In an embodiment, each of the pair of reinforcing tubes (230l,r) joins to each of the respective pair of upper tubes (212l,r) at respective junction points (230lj and 230rj). The junction points (230lj and 230rj) are substantially in the middle along the length of reinforcing tubes (230l,r). Each of the pair of reinforcing tubes (230l,r) further extending downwards beyond the junction points (230lj and 230rj) to join to each of the respective pair of down tubes (214l,r).
[025] In an embodiment, the pair of side tubes 222 includes a left tube (222l) and a right tube (222r). Each of the pair of side tubes 222 is joined to the reinforcing member 230 at a substantially centre portion (232c) of the centre tube 232 at first tube ends (222r-f and 222l-f) of the pair of side tubes 222. The first tube end (222r-f) is joined to the second tube end (222l-f) by an interconnecting member 301. Each of the pair of side tubes 222 extends outwards and downwards from the centre portion (232c) and is joined to the pair of upper tubes (212l,r) at second tube ends (222r-s and 222l-s) of the pair of side tubes 222.
[026] In an embodiment, the pair of seat rails (290l,r) is directly mounted on and joined to the reinforcing member 230 without the use of any intermediary components. In an embodiment, the reinforcing structure 250 has a pair of seat rail mounting means (292l,r) for mounting the pair of seat rails (290l,r). The pair of seat rail mounting means (292l,r) is mounted on the reinforcing member 230. Each of the pair of seat rails (290l,r) being directly mounted on the reinforcing member 230 through the respective pair of seat rail mounting means (292l,r).
[027] In an embodiment, the pair of seat rail mounting means (292l,r) is mounted on the reinforcing member 230 near end portions (232l,r) of the centre tube member 232 and extends downward from each of the end portions (232l,r). The pair of seat rails (290l,r) is joined to the mounting means 292 at a location vertically below the centre portion (232c) of the reinforcing member 230.
[028] A lower pair of seat rails (290l) (shown in Figure 2C) extends downwards from a rear end of the pair of seat rails 290 and is joined to the engine mounting bracket 220.
[029] In an embodiment, a rear shock absorber of the vehicle 200 is directly mounted on the reinforcing structure 250. The rear shock absorber is mounted through a shock absorber mounting bracket 240. The shock absorber mounting bracket 240 is joined on substantially the centre portion (232c) of the centre tube 232 through a reinforcing plate 302. In an embodiment, the shock absorber mounting bracket 240 is welded to the reinforcing plate 302.
[030] It may be appreciated that the centre portion (232c) of the centre tube 232 acts as a load junction point since the load from both the shock absorber and the pair of seat rails (290l,r) through the brackets 292 is taken at this point.
[031] Advantageously, the shock absorber is mounted directly on the reinforcing member between the side tubes and the pair of seat rails. This obviates the need for a bend in the frame structure and thus adds to the rigidity. The shock absorber load is thus distributed uniformly across the frame assembly. Further, the space made available now above the seat rails as result of the frame assembly of the invention, provides better clearance pathway for the air filter of the vehicle since the pair of seat rails is directly mounted on the reinforcing member without the use of any intermediary component.
[032] The triangular Trellis type formation of the reinforcing structure provides distribution of load and as a result, prevents movement of the rear frame structure upwards due to pressure from the shock absorber.
[033] Further, since the pair of seat rails is joined to the reinforcing structure at a location vertically below the centre portion of the centre tube, which is also the junction point; the seat height in the vehicle is reduced appreciably and makes it easier for a rider to mount the vehicle. At the junction point, the load from the rear frame structure and the load from the shock absorber gets compensated and is equally distributed. This strengthens the structural integrity of the junction point and thereby prevents loosening of the bolts and joints from the junction point.
[034] The frame assembly provided by the invention obviates the need for a reinforcing member bracket and thereby enables more space and optimal space utilisation in the vehicle with respect to mounting space and size of the other components of the vehicle. Thus, the invention provides increased clearance space while maintaining conventional vehicle layout.
[035] In the present invention, the structure of the rear frame is not bent or moulded with respect to the load points and is assembled directly in the reinforcing member without any bend. This increases the structural integrity and rigidity of the frame, and thereby increases the strength of the rear frame.
[036] While the present invention has been described with respect to certain embodiments, it will be apparent to those skilled in the art that various changes and modification may be made without departing from the scope of the invention as defined in the following claims.