Claims:I/We Claim

1. A swing arm assembly (110) for a two wheeled vehicle (100), said swing arm (110) comprising:
a pair of arms (111), each of said pair of arms (111) being disposed substantially parallel to each other, and
each arm (111) of said pair of arms (111) being connected with each other through a plurality of gussets (112),
wherein each arm (111) of said pair of arms (111) inclduing:
an outer enclosure (111A); and
an inner enclosure (111B), said outer enclosure (111A) and said inner enclosure (111B) being integrated with each other,
wherein said inner enclosure (111B) being mechanically connected with each of said plurality of gussets (112), and
said inner enclosure (111B) having a convex region (111C), said convex region (111C) being disposed towards said plurality of gussets (112).
2. The swing arm assembly (110) as claimed in claim 1, wherein said convex region (111C) being covered by a gusset from plurality of gussets (112), said gussets (112) being configured with a concave region conforming to said convex region (111C), when viewed from top.
3. The swing arm assembly (110) as claimed in claim 1, wherein said plurality of gussets (112) include a top gusset (112’) and a bottom gusset (112’’), wherein said top gusset (112’) being integrally attached with each of said pair of arms (111).
4. The swing arm assembly (110) as claimed in claim 3, wherein said top gusset (112’) being connected to a frame (101) of said vehicle (100) through a receiving member (113), said receiving member (113) being configured for receiving a force from said frame (101).
5. The swing arm assembly (110) as claimed in claim 4, wherein said receiving member (113) being connected with a shock absorber (104), said shock absorber (104) being attached with said frame (101) at a first distal end and said shock absorber (104) being attached with said receiving member (113) at a second distal end.
6. The swing arm assembly (110) as claimed in claim 1, wherein inner enclosure (111B) being welded with said outer enclosure (111A), and a first weld-line (114) representing a welding connection between said outer enclosure (111A) and said inner enclosure (111B), wherein said first weld-line (114) being formed between said outer enclosure (111A) and said inner enclosure (111B) when viewed from top of said swing arm (110).
7. The swing arm assembly (110) as claimed in claim 3, wherein inner enclosure (111B) being welded with said top gusset (112’), and a second weld-line (115) represents welding connection between said inner enclosure (111B) and said top gusset (112’), wherein said second weld-line (115) being formed on said inner enclosure (111B) when viewed from top of said swing arm (110).
8. The swing arm assembly (110) as claimed in claim 6 and claim 7, wherein said first weld-line (114) and said second weld-line (115) being configured away at a predetermined distance.
9. The swing arm assembly (110) as claimed in claim 8, wherein said first weld-line (114) being parallel to said second weld-line (115).
10. The swing arm assembly (110) as claimed in claim 8, wherein said second weld-line (115) being convex in shape when viewed from top of said swing arm (110), wherein said convex shape being formed towards said plurality of gussets (112).
11. The swing arm assembly (110) as claimed in claim 1, wherein said convex region (111C) of the inner enclosure (111B) adjoins said plurality of gussets (112) for improving stress bearing capability of said inner enclosure (111B) and said plurality of gussets (112).
, Description:TECHNICAL FIELD
[0001] The subject matter described herein, in general, relates to a rear suspension for a two wheeled vehicle and more particularly to a swing arm assembly for a two wheeled vehicle.
BACKGROUND
[0002] Generally, in a two wheeled vehicle, a vehicle frame assembly acts as a skeleton for the vehicle that supports the vehicle loads. A front portion of the frame assembly connects to a front wheel through one or more front suspension(s). The frame assembly extends rearward of the vehicle, where a rear wheel is connected to a swing arm assembly. The swing arm assembly receives a downward force from the frame assembly. Also, the swing arm assembly acts as a support member for one or more rear suspensions and other vehicular parts which include the rear wheel and a shock absorber assembly.

BRIEF DESCRIPTION OF THE DRAWINGS
[0003] The present invention is described with reference to an embodiment of a swing arm assembly for a two wheeled vehicle along with the accompanying figures. The same numbers are used throughout the drawings to reference like features and components.
[0004] Non-limiting and non-exhaustive embodiments of the invention are described with reference to the following figures, wherein like reference numerals refer to like parts throughout the various views unless otherwise specified. It should be appreciated that the following figures may not be drawn to scale.
[0005] Descriptions of certain details and implementations follow, including a description of the figures, which may depict some or all of the embodiments described below, as well as a discussion of other potential embodiments or implementations of the inventive concepts presented herein. An overview of embodiments of the invention is provided below, followed by a more detailed description with reference to the drawings.
[0006] Fig. 1 illustrates perspective view of the swing arm assembly of an existing art.
[0007] Fig. 2 illustrates a left side view of a two wheeled vehicle, in accordance with an embodiment of the present subject matter.
[0008] Fig. 3 illustrates a rear portion of the left side view of the two wheeled vehicle, in accordance with an embodiment of the present subject matter.
[0009] Fig. 4 illustrates a left side view of the rear portion of a frame assembly and a swing arm assembly of the two wheeled vehicle, in accordance with an embodiment of the present subject matter.
[00010] Fig. 5 illustrates a top view of the swing arm assembly, in accordance with an embodiment of the present subject matter.
[00011] Fig. 6 illustrates a top view of the swing arm assembly, in accordance with an embodiment of the present subject matter.
DETAILED DESCRIPTION
[00012] Generally, the frame assembly is made of tubular sections, channels or like, that are formed by hydroforming process or other processes that involve welding, rolling, steel extrusion or extrusion of other metal alloys. Similarly, the swing arm is also made by hydroforming process and through various other metal or alloy extrusion processes including welding. The swing arm comprises of more than one arm members that supports various vehicular parts made of different materials.
[00013] Conventionally the swing arm assembly include two substantially parallel arms and a portion with load bearings portion. The load bearing portions accommodates a rear shock absorber. The load bearing portion is also known as receiving portion because it receives downward load from the frame assembly. In conventional swing arms sheet metal arm are welded and joined which increase the stiffness of the swing arm. The swing arm is capable of bearing load of the rider and tolerate shocks produced while riding the motorcycle in uneven road conditions. Therefore, adequate strength and the stiffness of swing arm assembly is primary important feature. Any variation in design of the swing arm to increase stiffness also warrants change of shape and size of swing arm and the corresponding parts connecting the changed portion of the swing arm. Any change in corresponding connecting parts of the swing arm particularly the frame assembly or the rear wheel also disturbs the structure and shape of the vehicle. Swing-arms are typically made of steel extrusions of geometrical shapes like circle, oval etc., which, owing to its nature of design, has restriction in changing the strength and stiffness in local areas of the swing-arm.
[00014] As an alternative, cast swing-arms made of sheet metal are also used which are light in weight and of complex three-dimensional geometries so that they can achieve desired local stiffness. While designing a sheet metal based swing arm, various geometrical properties must be taken into consideration to achieve desired stiffness. One such property is section modulus. The section modulus is a geometrical property for any given cross-section measuring strength of that section. Higher the section modulus of the given cross-section, the more the resistive it becomes to bending. In other words, the section modulus is used to determine the stiffness of the object and approximate how much stress the object would withstand to remain in the elastic region.
[00015] In conventional swing arm assembly, often a shock absorber assembly is connected to the swing arm assembly but the load from the shock absorber assembly is not adequately and proportionally transmitted to all portions of the swing arm assembly. The conventional swing arms lacks desired stiffness and its inability to properly receive and transmit load from the shock absorber assembly.
[00016] In existing designs, each of the arm of the swing arm assembly is constructed by integrating an inner enclosure and an outer enclosure which are welded with each other. The integration of the inner enclosure and the outer enclosure is achieved by welding. Further, the arms or a side tubes of the swing arm assembly are connected with each other through a plurality of gussets or a plurality of bridge tubes with higher thickness and additional welding span. In swing arms with the plurality of gussets or bridge tubes, a major problem arises regarding connection of the plurality of gussets with the each of the arms of the swing arm assembly. If each arm of the swing arm assembly is made by welding the inner enclosure and the outer enclosure a weld line is formed representing the welding joint/ welding connection between both the enclosures of the arm. Due to limited availability of area, the plurality of gussets is often welded in vicinity of the weld-line between the inner enclosure and the outer enclosure. So much so, the welding joint of the gussets and the inner enclosure may overlap the welding joint of the inner enclosure and the outer enclosure. This overlap reduces the strength of the swing arm. Additionally, in another existing design, a hot zone is formed near the welding joint between the inner enclosure and the outer enclosure. It is also not desirable, that the plurality gussets are welded to the inner enclosure in the hot zone. If a connection of the plurality of gussets on the hot zone is done, the strength of the arm is negatively impacted.
[00017] Further, in conventional fabricated tube type swing arm construction, it is not possible to increase the section locally wherever high stress is observed. Moreover, manufacturing of fabricated tube type swing arm with different cross sections by swaging is difficult due to ejection problems during manufacturing. The primary aim of the present subject matter is to locally increase the stress bearing ability of the given cross-section thereby achieving a frugal design. The cross-section would be a load receiving portion of the swing arm assembly. Generally, the gussets and the inner enclosure of the swing arm assembly directly receive the load from the frame assembly.
[00018] The present subject matter addresses the aforementioned problems and other problems of known art. Hence, it is an objective of the present subject matter is to provide an improved swing arm assembly for a two-wheeled vehicle which has higher stiffness and strength. Additionally, the present subject matter aims to prevent any increase in the width or compactness of the vehicle.
[00019] To this end, the present invention discloses A swing arm assembly for a two wheeled vehicle. The swing arm is comprising: a pair of arms substantially parallelly disposed to each other and the pair of arms connected by a plurality of gussets. Each of the arm of the pair of arms comprises: an outer enclosure and an inner enclosure. The outer enclosure and the inner enclosure are integrated with each other to form each of the arm. Further, the inner enclosure is integrated with the plurality of gussets. The inner enclosures comprises a convex region towards the plurality of gussets such that the convex region adjoins the plurality of gussets to improve the stress bearing capability of the inner enclosure and the plurality of gussets.
[00020] In an embodiment of the present subject matter, since the inner enclosure of the swing arm is welded with the plurality of gussets, the convex region of the inner enclosure is covered by the plurality of gussets. The coverage by the gussets is visible from a top view.
[00021] In an embodiment of the present subject matter, the plurality of gussets includes a top gusset and a bottom gusset. The top gusset and the bottom gusset are integrated with each other and act as a bridge member between the two arms of the swing arm assembly.
[00022] In an embodiment of the present subject matter, the top gusset is connected to a frame of the vehicle through a receiving member. The receiving member supports a connecting tube or a shock absorber. A first distal end of the connecting tube or the shock absorber is connected to the frame of the vehicle and a second distal end of the connecting tube or the shock absorber is connected to the receiving portion. The receiving portion is disposed on a surface of the top gusset.
[00023] In an embodiment of the present subject matter, the inner enclosure of the arm is welded to the outer enclosure of the arm and a first weld-line is formed between the inner enclosure and the outer enclosure representing the welding connection of the inner enclosure and the outer enclosure. Similarly, the inner enclosure and the top gusset are welded with each other such that the top gusset is welded on a surface of the inner closure. The welding connection between the inner enclosure and the top gusset is represented by a second weld-line. Further the first weld-line and the second weld-line are at predetermined distance away from each other.
[00024] In an embodiment, the first weld-line and the second weld-line are parallel to each other. Whereas, in another embodiment, the second weld-line is convex in shape and the convex shape is towards the plurality of gussets.
[00025] The present subject matter is further described with reference to accompanying figures. It should be noted that the description and figures merely illustrate the principles of the present subject matter. Various arrangements may be devised that, although not explicitly described or shown herein, encompass the principles of the present subject matter. Moreover, all statements herein reciting principles, aspects, and examples of the present subject matter, as well as specific examples thereof, are intended to encompass equivalents thereof.
[00026] The foregoing disclosure is not intended to limit the present disclosure to the precise forms or particular fields of use disclosed. As such, it is contemplated that various alternate embodiments and/or modifications to the present disclosure, whether explicitly described or implied herein, are possible in light of the disclosure. Having thus described embodiments of the present disclosure, a person of ordinary skill in the art will recognize that changes may be made in form and detail without departing from the scope of the present disclosure. Thus, the present disclosure is limited only by the claims.
[00027] In the foregoing specification, the disclosure has been described with reference to specific embodiments. However, as one skilled in the art will appreciate, various embodiments disclosed herein can be modified or otherwise implemented in various other ways without departing from the spirit and scope of the disclosure. Accordingly, this description is to be considered as illustrative and is for the purpose of teaching those skilled in the art the manner of making and using various embodiments of the disclosure. It is to be understood that the forms of the disclosure herein shown and described are to be taken as representative embodiments. Equivalent elements, materials, processes or steps may be substituted for those representatively illustrated and described herein. Moreover, certain features of the disclosure may be utilized independently of the use of other features, all as would be apparent to one skilled in the art after having the benefit of this description of the disclosure. Expressions such as “including”, “comprising”, “incorporating”, “consisting of”, “have”, “is” used to describe and claim the present disclosure are intended to be construed in a non-exclusive manner, namely allowing for items, components or elements not explicitly described also to be present. Reference to the singular is also to be construed to relate to the plural.
[00028] Further, various embodiments disclosed herein are to be taken in the illustrative and explanatory sense, and should in no way be construed as limiting of the present disclosure. All joinder references (e.g., attached, affixed, coupled, connected, etc.) are only used to aid the reader's understanding of the present disclosure, and may not create limitations, particularly as to the position, orientation, or use of the systems and/or methods disclosed herein. Therefore, joinder references, if any, are to be construed broadly. Moreover, such joinder references do not necessarily infer that two elements are directly connected to each other.
[00029] Additionally, all numerical terms, such as, but not limited to, “first”, “second”, “third”, “primary”, “secondary”, “main” or any other ordinary and/or numerical terms, should also be taken only as identifiers, to assist the reader's understanding of the various elements, embodiments, variations and/or modifications of the present disclosure, and may not create any limitations, particularly as to the order, or preference, of any element, embodiment, variation and/or modification relative to, or over, another element, embodiment, variation and/or modification.
[00030] It will also be appreciated that one or more of the elements depicted in the drawings/figures can also be implemented in a more separated or integrated manner, or even removed or rendered as inoperable in certain cases, as is useful in accordance with a particular application. Additionally, any signal hatches in the drawings/figures should be considered only as exemplary, and not limiting, unless otherwise specifically specified.
[00031] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.
[00032] Fig. 1 illustrates a swing arm assembly (110) of an existing art. As per the illustration, the swing arm assembly (110) includes a plurality of the arms (111). Each of the arm (111) is also referred as an arm member (111). Each of the arm (111) includes an outer enclosure (111A) and an inner enclosure (111B). The outer enclosure (111A) and the inner enclosure (111B) are welded with each other to form the arm (111). Upon welding of the inner enclosure (111B) with the outer enclosure (111A) a weld joint or a first weld-line (114) is formed. The first weld-line (114) represents the welding connection between the inner enclosure (111B) and the outer enclosure (111A). Further, a plurality of gussets (112) are integrally attached with the inner enclosure (111B). The integration of the plurality of gussets (112) with the inner enclosure (111B) is achieved through welding of the plurality gussets (112) on the surfaces of the inner enclosure (111B). The plurality of gussets (112) includes a top gusset (112’) and a bottom gusset (112’’). As per the illustration, the top gusset (112’) is welded on a first surface of the inner enclosure (111B). As an outcome of welding between the inner enclosure (111B) and the top gusset (112’), a second weld-line (115) is formed on the first surface of the inner enclosure (111B). As shown in the illustration, the first weld-line (114) and the second weld-line (115) are formed in close proximity of each other. So much so, the second weld-line (115) is formed in a hot zone surrounding the first weld-line (114). When viewed from a perspective view, a distance between the first weld-line (114) and the second weld-line (115) is almost negligible or barely minimum.
[00033] Fig. 2 illustrates a left side view of a two wheeled vehicle (100), in accordance with an embodiment of the present subject matter. The two wheeled vehicle (100) includes a frame assembly (101) supporting a front wheel (110) and a rear wheel (102). The front wheel (110) and the rear wheel (102) are rotatably supported by a front suspension system (120) and a rear suspension system (125), respectively. In one embodiment, the rear wheel (102) is additionally supported by a swingarm (not labelled). The front wheel (110) is provided with a front wheel brake (130). In the present embodiment, the front wheel brake (130) is a disc brake. However, the front wheel brake (130) can be a drum brake or any other brake.
[00034] In the present embodiment, a power unit (140) is mounted to a front portion of the frame assembly (101). The power unit (140) is disposed substantially below a fuel tank (145) and rearward to the front wheel (110). Further, a carburetor or a fuel injection system or the like (not shown) supplies air-fuel mixture to the power unit (140) including an internal combustion engine. Further, the front wheel (110) is pivotally supported by the frame structure (101) and a handle bar assembly (150) is functionally connected to the front wheel (110) for maneuvering the vehicle (100). The handle bar assembly (150) supports an instrument cluster, vehicle controls including throttle, clutch, or electrical switches. Further, the handle bar assembly (150) supports at least one independent brake actuation lever.The vehicle (100) inlcudes another lever that is a brake pedal (not shown) disposed adjacent to a rider foot support structure (185).
[00035] Further, a seat assembly (180) is attached to the frame assembly (101) in a rearward direction from the fuel tank (145). The rider can operate the vehicle (100) in a seated position on the seat assembly (180). Moreover, the vehicle (100) includes a pair of rider foot support structure (185) disposed on either side of the vehicle (100) for the user to rest feet. The foot support structure (185) being secured to the frame structure (101) of the vehicle (100).
[00036] Further, the two wheeled vehicle (100) includes a front fender (195) covering at least a portion of the front wheel (110) and a rear fender (190) covering at least a portion of the rear wheel (102). Also, the vehicle (100) is provided with plurality of panels including front panel (170A) and rear panel (170B) mounted to the frame structure (101) and covering the frame structure (101) and/or parts of the vehicle (100). Also, the vehicle (100) is employed with plurality of mechanical, electronic, and electromechanical system including an anti-lock braking system, a vehicle safety system, or an electronic control system.
[00037] Fig. 3 illustrates rear portion of the left side view of the two wheeled vehicle (100), in accordance with an embodiment of the present subject matter. As per the illustrated embodiment, a swing arm assembly (110) is supporting a rear portion of the frame assembly (101) and the rear wheel (102). The swing arm assembly (110) is an essential component of the rear suspension system for the two wheeled vehicle (100). The swing arm assembly (110) receives a downward force from the frame assembly (101) and assists the two wheeled vehicle (100) in tolerating shocks during vehicle running condition on bumpy roads. The receiving member (113) is attached on a top surface of the swing arm assembly (110). The receiving member (113) provides a linkage between the frame assembly (101) and the swing arm assembly (110) through a connecting member (103). As per a preferred embodiment, the connecting member is a shock absorber (104) shown in Fig 4.
[00038] Fig. 4 illustrates a left side view of the rear portion of a frame assembly (101) and the swing arm assembly (110) of the two wheeled vehicle (100), in accordance with an embodiment of the present subject matter. As per the illustrated embodiment, a shock absorber (104) is mounted on a top portion of the swing arm assembly (110). The shock absorber (104) acts as a link between the frame assembly (101) and the swing arm assembly (110). The shock absorber (104) receives and absorbs vehicle shocks from the ground during vehicle running condition. Also, the shock absorber (104) receives and absorbs the downward force from the frame assembly (101).
[00039] Fig. 5 illustrates a top view of the swing arm assembly (101), in accordance with an embodiment of the present subject matter. As per the illustrated embodiment, each of the arm (111) of the swing arm assembly (110) is substantially parallel to each other. Further, each of the arm (111) of the swing arm assembly (110) are connected through the plurality of gussets (112). As per illustrated top view, the top gusset (112’) is welded to the inner enclosure (111B) of each of the arm (111). As per the illustration, the top gusset (112’) is welded on a top surface of the inner enclosure (111B). As per the illustrated embodiment, the second weld line (115) indicating the weld joint between the top gusset (112’) and the top surface of the inner enclosure (111B) is at a predetermined distance away from the first weld-line (114). The first weld-line (114) indicates the weld joint between the inner enclosure (111B) and the outer enclosure (111A). As per the illustrated embodiment, the second weld-line (115) is convex towards the plurality of the gussets (112) to ensure that the predetermined distance between the first weld line (114) and the second weld-line (115) is at least “a”. The predetermined distance (a) ensures that the second weld line (115) does not overlaps the first weld-line (114) or the second weld line (115) is away from the hot regions or heat affected zones (HAZ) of the first weld-line (114). The hot regions of the first weld-line (114) are the regions which receives maximum temperature rise due to welding of the outer enclosure (111A) and the inner enclosure (111B).
[00040] As per the illustrated embodiment, the inner enclosure is having a convex region (111C). The convex region (111C) is convex in shape towards the plurality of gussets (112). The convex region (111C) of the inner enclosure (111B) adjoins the plurality of gussets (112). The convex region (111C) enables in improvement of stress bearing capability of the inner enclosure (111B) and the plurality of gussets (112). The convex region (111C) increases the area of the cross section adjoining the plurality of gussets (112) and thereby improve the section modulus of the cross section adjoining the plurality of gussets (112). As per an aspect of the present invention, the convex region (111C) is a local lateral inward bulging profile, where the inner bulge is located at the region of the gussets (112). As per another aspect, the gussets (112) are configured with a lateral inward recess or concave region conforming to the convex region (111C) of the inner enclosure (111B) thereby enabling the second weld line (115) to be considerably away from the first weld line (114).An additional advantage of the aforementioned configuration is that, a shape of the outer enclosure (111A) of the arm (111) remains intact and undisturbed. Therefore, the width of the swing arm assembly (111) is prevented from any increase towards an outward side of the vehicle. Thereby, the vehicle width as a whole is also not increased.
[00041] Fig. 6 illustrates a top view of the swing arm assembly (101), in accordance with an embodiment of the present subject matter. As per the illustrated embodiment, the first weld-line (114) is parallel to the second weld-line (115). The parallel arrangement of the first weld-line (114) and the second weld-line (115) ensures that the second weld-line (115) is sufficiently away from the hot zones of the first weld-line (114) and the second weld-line (115) never overlaps the first weld-line (114).
[00042] 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.
 

LIST OF REFERENCE NUMERALS
100: Vehicle
101: Frame assembly
102: Rear Wheel
103: Connecting Tube
104: Shock Absorber
110: Swing Arm Assembly
111: Arm
111A: Outer Enclosure
111B: Inner Enclosure
112: Plurality of Gussets
112’: Top Gusset
112’’: Bottom Gusset
113: Receiving Member
114: First Weld Line
115: Second Weld Line
120: Front Suspension System
125: Rear Suspension System
140: Power Unit
145: Fuel Tank
150: Handle Bar Assembly
170A: Front Panel
170B: Rear Panel
180: Seat Assembly
185: Foot Support Structure
190: Rear Fender
195: Front Fender