Claims:We Claim:
1. A frame assembly (200) for a motor vehicle (100), said frame assembly (200) comprising:
a front structure (101), wherein said front structure configured to support at least one front wheel (130); and
a rear structure (205), said rear structure (205) comprising:
one or more rear members (210, 211), wherein each of said one or more rear members (210, 211) formed by a first sub-member (210) and a second sub-member (211), and said first sub-member (210) and said second sub-member (211) being co-joined, wherein
said first sub-member (230) comprises a first cross-sectional area (A1) being larger than a second cross-sectional area (A2) of said second sub-member (240).
2. The frame assembly (200) as claimed in claim 1, wherein said first sub-member (230) is a partially closed structure and said second sub-member (240) is a plate-shaped structure configured to be co-joined to the first sub-member (230) and thereby forming a closed cross-section.
3. The frame assembly (200) as claimed in claim 1, wherein said first sub-member (230) comprises a first outer width (W1) and said second sub-member (240) comprises a second outer width (W2), wherein said second outer width (W2) is at least more than or equal to the first outer width (W1).
4. The frame assembly (200) as claimed in claim 3, wherein said second outer width (W2) is larger than said first outer width (W1), and wherein a weld joint (260) is provided between an outer facing side (OFS) of said first sub-member (230) and inward facing side (IFS) of said second sub-member (240).
5. The frame assembly (200) as claimed in claim 4, wherein said first sub-member (230) comprises two end regions (230A, 230B) disposed to abut the inward facing side (IFS) of the second sub-member (240), wherein said two end regions (230A, 230B) are disposed along an imaginary vertical plane or along a plane disposed at angle with respect to the imaginary vertical plane.
6. The frame assembly (200) as claimed in claim 1, wherein said second sub-member (240) is provided with plurality of depressions (250, 251, 252) selectively provided along at least a length thereon.
7. The frame assembly (200) as claimed in claim 6, wherein said plurality of depressions (250, 251, 252) are projecting inward, and wherein each of said plurality of depressions (250, 251, 252) are configured with a pre-determined profile (PP1, PP2, PP3) and a pre-determined depth (D).
8. The frame assembly (200) as claimed in claim 1, wherein said one or more rear members (210, 211) are divided into plurality of portions (206, 207, 208), and a front portion (206), a mid-portion (207), and a rear-portion (208) forming said plurality of portions, and wherein at least one depression (250, 251, 252) is selectively disposed on each of said plurality of portions (206, 207, 208).
9. The frame assembly (200) as claimed in claim 8, wherein said plurality of portions (206, 207, 208) are formed as discrete parts for each of said first sub-member (230) and said second sub-member (240).
10. The frame assembly (200) as claimed in claim 8, wherein said plurality of portions (206, 207, 208) are integrally formed to for each of said first sub-member (230) and said second sub-member (240).
11. The frame assembly (200) as claimed in claim 8, wherein said front-portion (206) is formed of 40% of a length of the rear structure (205) taken from a front end (225) thereof and said rear portion (208) is formed of 20% of a length of the rear structure (205) taken from a rear end thereof, and wherein a mid-portion (207) formed of the remaining rear structure (205) between the front-portion (206) and the rear portion (208).
12. The frame assembly (200) as claimed in claim 11, wherein said plurality of depressions (250, 251, 252) are each provided with a third width (W3) at the pre-determined portion, said third width (W3) is substantially equal to a first inner width (W11) of first sub-member (230) at the corresponding pre-determined portion.
13. The frame assembly (200) as claimed in claim 1, wherein said first sub-member (230) and said second sub-member (240) are made of dissimilar materials.
14. The frame assembly (200) as claimed in claim 1, wherein said front structure (101) comprises a head tube (106) and main tube (107), wherein a rear portion of the main tube (107) is provided with a first bridge member (215) extending substantially in a lateral direction (RH-LH) and a front end (225) of the one or more rear members (210, 211) of the rear structure (205) is connected to the first bridge member (215).
15. A rear structure (205) of a frame assembly (200) for a motor vehicle (100), said rear structure (205) comprising:
one or more rear members (210, 211), each of said one or more rear members comprising:
a first sub-member (230) having a first cross-sectional area (A1); and
a second sub-member (240) having a second cross-sectional area (A2), wherein said second cross-sectional area (A2) being smaller than the first cross-sectional area (A1),
wherein said one or more members (210, 211) comprising a front end (225), wherein said front end (225) comprising a first sectional profile (SP1) being substantially larger than a sectional profile taken at a portion away from the front end (225).
16. The rear structure (205) as claimed in claim 14, wherein said front end (225) comprises a high load region (R1) and said region is configured to have a trapezoidal profile and of any known geometric profile when viewed from a lateral side (RH, LH) and said front end (225) with a first height (H1) taken in up-down direction (UW-DW) substantially greater than a second height (H2) taken at a region away from the front end (225).
17. The rear structure (205) as claimed in claim 14, wherein said front end (225) comprises a sectional profile (SP1) taken along an axis (B-B’) orthogonal to an axis of the rear member (210 or 211), and said sectional profile (SP1) comprises a first height (H1) greater than a first lateral width (LW1) thereat.
18. The rear structure (205) as claimed in claim 14, wherein said front end (225) is provided with a bush member (275), said bush member (275) between the first sub-member (230) and the second sub-member (240) and secured thereto.
19. The rear structure (205) as claimed in claim 14, wherein said first sub-member (230) comprises an inner surface (IS), wherein an end surface of a connecting link-sleeve (291) abuts with the inner surface (IS), and wherein a mounting axle (292) extends between a bush member(s) 275 of the one or more rear members (210, 211) and said connecting link-sleeve (291) encloses at least a portion of the mounting axle (292). , Description:TECHNICAL FIELD
[0001] The present subject matter relates to a saddle ride-type motor vehicle and more particularly to a frame assembly for the saddle ride-type motor vehicle.
BACKGROUND
[0002] Generally, a saddle ride-type motor vehicle comprises a frame assembly that acts a skeleton or a structural member. A power unit, constituted by at least one of an internal combustion engine or an electric motor, acts as a prime mover. At least one front wheel and at least one rear wheel are connected to the frame assembly through respective suspension systems. The power unit is functionally connected to the front wheel or rear wheels for driving and providing motion. Further, the power unit is either fixedly or swingably supported by the frame assembly. Various system components of the motor vehicle are also supported by the frame assembly. For example, a utility box with storage space, a fuel tank, a seat assembly where the rider and pillion sit are supported by the frame assembly. Certain category of the saddle ride-type motor vehicles are provided with a step-through portion (for load-carrying or foot-rest functions), which is achieved by virtue of the construction of the frame assembly. Thus, the frame assembly forms a critical component of the motor vehicle.
BRIEF DESCRIPTION OF DRAWINGS
[0003] The detailed description is described with reference to the accompanying figures, which is related to a saddle ride-type motor vehicle being one embodiment of the present invention. However, the preset invention is not limited to the depicted embodiment(s). In the figures, the same or similar numbers are used throughout to reference features and components.
[0004] Fig. 1 illustrates a left-side view of an exemplary motor vehicle, in accordance with an embodiment of the present subject matter.
[0005] Fig. 2 (a) illustrates a schematic isometric view of a frame assembly, in accordance with an embodiment of the present subject matter.
[0006] Fig. 2 (b) illustrates a schematic left-side view of the frame assembly along with a power unit, in accordance with an embodiment of the present subject matter.
[0007] Fig. 2 (c) illustrates a sectional view of a rear structure taken along axis A-A’, in accordance with an embodiment of the present subject matter.
[0008] Fig. 2 (d) illustrates a schematic sectional of a first sub-member and a second sub-member, in accordance with an embodiment of the present subject matter.
[0009] Fig. 2 (e) illustrates another schematic sectional view of a rear member of the rear structure, in accordance with an embodiment of the present subject matter.
[00010] Fig. 2 (f) illustrates a top view of a frame assembly, in accordance with an embodiment of the present subject matter.
[00011] Fig. 2 (g) is an enlarged view of a region of the frame assembly 200, in accordance with an embodiment of the present subject matter.
[00012] Fig. 2 (h) illustrates an enlarged side view of a front end of a rear member, in accordance with an embodiment of the present subject matter.
[00013] Fig. 2 (i) illustrates a sectional view of the frame assembly taken along axis B-B’, in accordance with an embodiment as illustrated in Fig. 2 (f).
[00014] Fig. 2 (j) illustrates another schematic isometric sectional view of the rear structure taken along axis B-B’, in accordance with an embodiment.
[00015] Fig. 3 (a) depicts perspective view of a motor vehicle, in accordance with another embodiment of the present subject matter.
[00016] Fig. 3 (b) depicts a side schematic sectional-view of a motor vehicle, in accordance with another embodiment of the present subject matter.
[00017] Fig. 4 (a) illustrates a top view of a portion of a motor vehicle, in accordance with yet another embodiment of the present subject matter.
[00018] Fig. 4 (b) illustrates an isometric view of a motor vehicle with partially exploded components, in accordance with yet another embodiment of the present subject matter.
[00019] Fig. 4 (c) a schematic side sectional-view of a portion of the motor vehicle, in accordance with yet another embodiment of the present subject matter.
DETAILED DESCRIPTION
[00020] Typically, in the saddle ride-type motor vehicles, the frame assembly is made of tubular members. Generally, the frame assembly comprises a head tube and a main tube. The head tube rotatably supports a steering system. At least one front wheel forms part of the steering system, which is used for maneuvering the motor vehicle. The main tube is typically made of single tubular member. The main tube is provided with a single bend and is adapted to support a fuel tank or a floorboard or a power unit (fixedly) depending on the layout of the motor vehicle. The frame assembly comprises one or more rear frames, which are also formed by tubular members. The rear frames extend rearward from the main tube. The rear frames are provided with multiple bends in order to sync with a rear layout of the motor vehicle.
[00021] With ever improving technological advancements, the motor vehicles are becoming safer and more reliable to operate. At the same time, the various systems on the motor vehicle are increasing. In order to package various additional features in the motor vehicle, the frame assembly of the motor vehicles has to made stronger. Typically, the weight of the frame assembly increases due to increase in thickness of the tubular member or due to addition of gussets at critical region in order to withstand the loads. In addition, the additional features on the vehicle, come with their associated system, that are to be mounted on to the frame assembly. This increases overall weight of the motor vehicle. An increase in weight of the motor vehicle, affects the performance of the motor vehicles. The riding dynamics is also affected adversely. For example, the inertia of the motor vehicle will be high and more fuel or energy is utilized during start or hill climb making them poor in terms of fuel efficiency. Moreover, the emissions are also higher in such heavier motor vehicle and may require sophisticated emission treatment systems, which increase overall cost of the system. Moreover, the heavier motor vehicles are difficult to handle in certain riding conditions, which require slow movement (say traffic conditions) or city riding conditions that require frequent maneuvering. Thus, there is a challenge to reduce the weight of the motor vehicle.
[00022] Further, the frame assembly comprises the rear frames, which are formed by a large single tubular structure or by two or more small tubular structure. Unlike the main tube of the frame assembly, the rear frames are to adapted to sync with the configuration of the motor vehicle. For example, the rear frames are bent at multiple portions in order to meet the technical specifications like seat height etc. The bending is higher in case of the motor vehicle with step-through portion. In the motor vehicle with step-through portion, the rear frames extend inclinedly rearward and thus, requires multiple bends. Bending of the tubular members has various associated problems like springback, warping or tube wrinkles, bend radius precision challenges etc.
[00023] For example, due to springback, mounting position of various components gets affected. The assembly of components is affected and even if the components are assembled, their function may get affected. For example, the aforementioned variations may add additional load on one side and that results in early failure of the component or part. Bending the rear frames with multiple bends may get structurally compromised due to changes in stiffness, tensile strength, thickness of material around the bends. The frame member that do not meet the structural requirements gets rejected resulting in waster of material, man hours and cost.
[00024] An additional challenge with the relatively small rear frames is that they have uniform cross-section about the entire length. Certain high load components like the power unit, rear suspension etc. are connected to the rear frames. In order to withstand the loads at these regions (of connection) multiple gussets are to be welded in those regions. However, welding the metal member, which has already undergone multiple bends adversely affects its structural strength owing to heat affected zone from welding temperatures. The entire thickness of the rear frames may be increased to withstand the loads at the connection regions. However, this increases the weight of the frame assembly and the motor vehicle, which is undesired. Thus, there exists a challenge to provide a frame assembly that is capable of addressing the aforementioned and other associated problems in the prior art.
[00025] Hence, the present subject matter provides a frame assembly for a motor vehicle. The frame assembly is having less weight and eliminates problems associated with multiple bends. The frame assembly provides structural stiffness to withstand the loads and achieve precise geometric dimensions. The features and the associated advantages are explained in the following paragraphs.
[00026] The frame assembly comprises of a front structure, which is configured to rotatably support at least one front wheel of the motor vehicle. The front structure can be formed by a head tube and a main tube. The main tube can be formed by a tubular member with a single bend or can be casted member. The frame assembly is provided with a structurally stiff and low-weight rear structure.
[00027] The rear structure comprises one or more rear members. Each of the rear members is formed by a first sub-member and a second sub-member. The first sub-member and the second sub-member co-joined or joined together by any known means. Further, the first sub-member comprises a first cross-sectional area being larger than a second cross-sectional area of the second sub-member. In one embodiment, the first sub-member and the second sub-member are made of sheet metal and are stamped to achieve the aforementioned cross-section.
[00028] In one embodiment, the first sub-member is a partially closed structure and has the first cross-sectional area which is larger. The second sub-member is a plate-shaped structure configured to be co-joined to the first sub-member. The first sub-member and the second form a closed cross-section, which provides improved strength to weight ratio as well as performance under stress.
[00029] In one embodiment, the rear member with the first sub-member comprises a first width and the second sub-member comprises a second width. The second width is provided to be at least equal to the first width. This enables in achieving the closed structure that is required and the edges of the first sub-member and the second sub-member can be welded or the like.
[00030] In one embodiment, the second width is larger than the first width whereby two end regions of the first sub-member abut the second sub-member in co-joined condition. A weld joint is provided between an outer facing side of said first sub-member and inward facing side of the second sub-member. The widths are configured to provide required land are for welding.
[00031] The first sub-member and the second sub-member that are stamped provide the flexibility of varying cross-section depending on load requirements with ease of manufacturing.
[00032] In one embodiment, the first sub-member comprises the two end regions, which are disposed along an imaginary vertical plane. This provides a C-shaped partially closed structure. In another embodiment, the two end regions are disposed in a plane, which is at an angle with respect to the imaginary vertical plane. In such configuration, the first sub-member has an asymmetrical profile unlike a symmetrical C-shape. In the aforementioned and other configurations, the second sub-member with plate shaped structure can be co-joined with the first sub-member.
[00033] In one embodiment, the second sub-member is provided with a plurality of depressions selectively disposed along at least a length thereon. The plurality of the depressions can be formed during the stamping process itself and does not require any additional manufacturing steps. In one embodiment, a plurality of depressions is selectively provided along at least a length of the first sub-member.
[00034] In one embodiment, the plurality of depressions is projecting inward when viewed along an axis of the rear member. Each of the plurality of depressions are configured with a pre-determined profile and a pre-determined depth. For example, each depression can be configured to have a respective profile shape of the rear member at that region. Each depression can be provided with different depth depending on a local strength requirement at that region of the rear member. In another embodiment, the plurality of depressions provided on the second sub-member is projecting outward when viewed along an axis of the rear member. Such a configuration is adapted in motor vehicle with substantial space formed between the rear member and the rear panel assembly and other adjacent parts thereof.
[00035] In one embodiment, the one or more rear members are divided into plurality of portions. For example, in one implementation, the plurality of portions includes a front portion, a mid-portion, and a rear-portion.
[00036] In one embodiment, at least one depression is selectively disposed on each of the plurality of portions to reinforce that particular region.
[00037] In one embodiment, the plurality of portions is formed by discrete parts. This enables in choosing a specific thickness and a specific material for the corresponding portion depending on load and other structural requirements.
[00038] In one embodiment, the plurality of portions is integrally formed to form the respective first sub-member and said second sub-member. This provide ease of manufacturing as the entire first sub-member and the second sub-member can be stamped at once to form the desired shape.
[00039] In one embodiment, the second sub-member is provided with a plurality of depressions, and the plurality of depressions are projecting inward. Each depression of the plurality of depressions are provided at a pre-determined portion on the second sub-member depending on strength requirements at that region.
[00040] In one embodiment, the plurality of depressions is provided with a third width at the pre-determined portion. The third width is substantially equal to a first inner width of first sub-member at the corresponding pre-determined portion. This provides alignment of the first sub-member and the second sub-member. For example, for a specific depression the third width is provided and the depression with the third width aligns only with a corresponding first inner width of the second sub-member, which enables in ease of alignment for co-joining.
[00041] In one embodiment, the front structure comprises a first bridge member extending substantially in a lateral direction and connected to a rear portion of the main tube of the front structure. In one embodiment, a front end of the one or more rear members of the rear structure is connected to the first bridge member.
[00042] In one embodiment, a front end of the rear member comprises a high load region, when viewed from lateral side. The high load region is configured to have a trapezoidal profile or any known geometric profile. The high load region has a larger area (cross-sectional area) when compared to the rest of the rear member. The first sub-member and the second sub-member formed by stamping enable in achieving the varying cross-section thereof. The rear member gets connected to the front structure through the front end.
[00043] In one embodiment, the front end has a first height taken in up-down direction, which is substantially greater than a second height taken at a region away from the front end. The larger cross-sectional area or the high load region is achieved by increasing height without largely affecting the width of the rear structure and correspondingly the width of the motor vehicle.
[00044] In one embodiment, the front end comprises a sectional profile taken along an axis orthogonal to an axis of the rear member, and the sectional profile comprises a height greater than a first lateral width thereat.
[00045] Thus, the frame assembly of the present subject matter provides a rear structure formed by rear member that does not require multiple bending process. The first sub-member and the second sub-member provide the structurally stiff hollow structure with optimal weight. The frame assembly provides all the structural and high precision (for assembly of components thereon) functionalities.
[00046] Need for additional gussets for reinforcing which need welding for connection are avoided.
[00047] The frame assembly of the present invention reduced variations in rear structure thereof and can be manufactured with reduced number of operations and with reduced rework thereby saving time and cost. Frame assembly rejections are reduced/ eliminated.
[00048] The balancing support system may be implemented in any two-wheeled vehicle or a three-wheeled motor vehicle. However, for the purpose of explanation and by no limitation, the balancing support system, and corresponding additional advantages and features are described through the following embodiments. Arrows wherever provided on top right corner of the figure represent direction with respect to motor vehicle. Arrow F represents forward direction, arrow R1 represents rearward direction, arrow UW represents upward direction and arrow DW represents downward direction. The present subject matter is further described with reference to accompanying figures. It should be noted that the description and figures merely illustrate 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.
[00049] Fig. 1 depicts a left side view of an exemplary motor vehicle 100, in accordance with an embodiment of the present subject matter. The motor vehicle 100 includes a frame assembly 200 (shown schematically with dotted lines) comprising a front structure 101 formed by a head tube 106, a main tube 107. The frame assembly 200 includes a rear structure 205. In the depicted embodiment, the frame assembly 200 defines a step-through portion 151. A front wheel 130 and a rear wheel 133 are rotatably supported by a front suspension system 131 and the rear suspension system 134, respectively. In one embodiment, the rear wheel 133 may be additionally supported by a swingarm (not shown).
[00050] In the present embodiment, a power unit 135 is swingably connected to the frame assembly 200 and is disposed substantially below a seat assembly 155 and rearward to the step-through portion 151. The power unit 135 includes a transmission system (not shown) for transferring power to the rear wheel 133. The transmission system may include a continuously variable transmission, an automatic manual transmission, a belt/chain drive. In one embodiment, the power unit 135 is an internal combustion engine. In another embodiment, the power unit 135 is an electric prime mover. In one another implementation, the power unit is fixedly mounted to the frame assembly 200 of the motor vehicle 100.
[00051] Further, the front wheel 130 is pivotally supported by the frame assembly 200 and a handle bar assembly 150 is functionally connected to the front wheel 130 for maneuvering the vehicle 100. The handle bar assembly 150 may support an instrument cluster, vehicle controls including throttle, clutch, or electrical switches. Further, a seat assembly 155 is supported by the frame assembly 200 and the rider can operate the vehicle 100 in a seated position on the seat assembly 155. Moreover, in the depicted embodiment, the vehicle 100 includes the step-through portion 151 formed between the handle bar assembly 150 and the seat assembly 155.
[00052] The vehicle 100 is provided with plurality of panels 170A, 170B, 170C mounted to the frame assembly 200 and covering the frame assembly 200 and/or parts of the vehicle 100. The plurality of panels includes a front panel 170A and a leg-shield 170B covering a head tube 106 of the frame assembly 200 in forward and rearward direction, respectively. Further, a rear panel assembly 170C is disposed substantially below the seat assembly 155. The rear panel assembly 170C substantially covers a utility box (not shown) disposed below the seat assembly 155 and also, covering at least a portion of the power unit 135. The motor vehicle 100 is provided a balancing support system 200, which is discussed in following description.
[00053] Fig. 2 (a) illustrates a schematic isometric view of a frame assembly, in accordance with an embodiment of the present subject matter. Fig. 2 (b) illustrates a schematic left-side view of the frame assembly assembled on vehicle 100 along with a power unit, in accordance with an embodiment of the present subject matter. The frame assembly 200 comprises a head tube 106, which is configured to rotatably support a steering shaft (not shown). In the depicted embodiment, a main tube 107 extends rearwardly downward from the head tube 106. Subsequently, the main tube 107 extends rearward in a longitudinal direction F-R of the motor vehicle 100. The frame assembly 200 comprises a rear structure 205. The rear structure 205 may be formed by one or more rear members. In one embodiment, a single rear member may extend reward disposed in-line with the main tube 107 which is also referred as a backbone frame structure. In one embodiment as illustrated, the rear structure 205 comprises a first rear member 210 and a second rear member 211. The first rear member 210 and the second rear member 211 are spaced apart in lateral direction RH-LH. In the depicted embodiment, the first rear member 210 and the second rear member 211 are extending rearward from a rear portion of the main tube 107.
[00054] The frame assembly 200 comprises a first bridge member 215 disposed at a rear end of the front structure 101, say at a rear end of the main tube 107 and the first bridge member 215 extends in the lateral direction RH-LH. A pair of floor frames 220A, 220B are disposed substantially parallel to a rear portion of the main tube 107. A front portion of the pair of floor frames 220A, 220B are secured to the main tube 107 and a rear portion of the pair of floor frames 220A, 220B are supported on the first bridge member 215. The pair of floor frames 220A, 220B are configured to support a floorboard (not shown) at the step-through portion 151. A front end 225 of the one or more rear members 210, 211 of the rear structure 205 is connected to the first bridge member 215.
[00055] In one embodiment, the rear structure 205/ first rear member 210 and the second rear member 211 are imaginarily divided in to three portions (separated by imaginary dotted lines shown in Fig. 2 (b)) viz. a front-portion 206, a mid-portion 207 and a rear-portion 208. In one implementation, the front-portion 206 is formed of 40% of a length of the rear structure 205 taken from a front end 225 thereof and a rear portion 208 is formed of 20% of a length of the rear structure 205 taken from a rear end thereof. A mid-portion 207 formed of the remaining rear structure 205 between the front-portion 206 and the rear portion 208. The percentages considered here are exemplary in nature and are not limiting, as they are subject to vary depending on the vehicle layout and structural requirements.
[00056] In one embodiment, the first rear member 210 and the second rear member 211 extends inclinedly rearward. The front end 225 of the rear members 210, 211 is connected to the first bridge member 215 by any known means. Further, subsequent to the front-portion 206, the mid-portion 207 extends at an angle with reference to the front-portion 206. The rear-portion 208 extends rearward from the mid-portion and is disposed at an angle with the mid-portion 207.
[00057] Further, the rear structure 205 comprises of a plurality of bridge members. A second bridge member 216 is provided at the front-portion 206 and is configured to support a front portion of a utility box (not shown) and a hinge joint of the seat assembly 155. A third bridge member 217 is provided to support a rear portion of the utility box. Furthermore, one or more bridges 218, 219 are provided to support a fuel tank, a rear panel assembly, a tail assembly, a rear fender etc. The rear structure supports various critical components of the motor vehicle 100 including the power unit 135. In one embodiment, the power unit 135 is swingably connected to rear structure 205 through a connecting link 290.
[00058] The first rear member 210 and the second rear member 211 are symmetrically formed or are in the form of a mirror image with respect a lateral center of the frame assembly 200. Hence, hereinafter the constructional features of any one of the rear members may be discussed in detail and the features are appliable to the other rear member as well. Each of the first rear member 210 and the second rear member 211 are formed of a first sub-member 230 and a second sub-member 240. The first sub-member 230 and the second sub-member 240 are co-joined or combined together by any known means. Further, the first sub-member 230 comprises a first cross-sectional area A1 being larger than a second cross-sectional area A2 of said second sub-member 240. The first sub-member 230 with the (larger) first cross-sectional area A1 is configured to have a partially closed structure. The second sub-member 240 has a plate shaped structure with the second cross-sectional area A2, being smaller than the first cross-sectional area. In one embodiment, the first sub-member 230 is disposed inward and the second sub-member 240 disposed outward. In one embodiment, each of the sub-member 230, 240 are sheet metal parts formed of the desired profile by stamping. The formation is not limited to stamping and may include any known similar process. The first sub-member 230 and the second sub-member 240 are stamped with the desired bends and profile along their length thereby reducing post-processing steps. The first sub-member 230 and the second sub-member 240 are co-joined to form a closed section.
[00059] Fig. 2 (c) illustrates a sectional view of the rear structure 205 taken along axis A-A’, in accordance with an embodiment of the present subject matter. Fig. 2 (d) illustrates a schematic sectional of a first sub-member and a second sub-member and Fig. 2 (e) illustrates another schematic sectional view of a rear member of the rear structure, in accordance with an embodiment of the present subject matter. Considering Figs. 2 (c) to 2 (e) in conjunction with Figs. 2 (a) & 2 (b), the first sub-member 230 and the second sub-member are co-joined. In one embodiment, the first sub-member 230 and the second sub-member 240 are co-joined by welding. The first sub-member 230 with the first cross-sectional area A1 is a partially closed structure like a C-shaped structure or any other partially closed structure. The second sub-member 240 with the second cross-sectional area A2, being relatively smaller, is a plate-shaped structure configured to be co-joined to the first sub-member 230. The first sub-member 230 and the second sub-member 240 form a closed cross-section. In one implementation, the first sub-member 230 is comprising a C-shaped cross-section and the second sub-member 240 is a plate like structure. The second sub-member 240 when co-joined with the first sub-member 230 forms the closed section. The first sub-member 230 is having a first outer width W1 taken in up-down direction UW-DW and the second sub-member 240 has a second outer width W2 taken in same direction. In one embodiment, the second outer width W2 is greater than or equal to (at least equal to) the first outer width W1 whereby the second sub-member 240 has a pre-determined area equal to or extending beyond the first outer width W1 of the first sub-member 230. In one embodiment, weld joint 260 is made between an outer facing side OFS of the first sub-member 230 and an inward facing side IFS of the second sub-member 240. Therefore, the weld joints 260 are provided on upper side & lower side and along entire length of the rear member 211/ 210. The first sub-member 230 comprises two end regions 230A, 230B that abut with the second sub-member 240. The two end regions 230A, 230B, in the depicted embodiment, are disposed along an imaginary vertical plane. In another embodiment, the two end regions 230A, 230B are disposed along a plane, which is disposed at angle with respect to the imaginary vertical plane depending on structural requirements.
[00060] Further, as depicted in Fig. 2 (a), the second sub-member 240 is provided with plurality of depressions 250, 251, 252. Similarly, plurality of depressions is also provided on the first rear member 210, which cannot be seen in the depicted views. The plurality of depressions 250, 251, 252 is selectively provided along at least a length thereon. For example, as shown in Fig. 2 (b), a first depression 250 is provided at the front-portion 206. Further, the front-portion 206 is configured to have a larger width at the front end 225 and the width recedes when moving towards the mid-portion 207. A second depression 251 is provided at the mid-portion 207 and a third depression 252 is provided at the rear-portion 208. In one embodiment, coincidentally, the depressions 250, 251, 252 are aligned with the three-portions 206, 207, 208. Thus, in one implementation, at least one depression 250, 251, 252 is selectively disposed on each of the plurality of portions 206, 207, 208. In another embodiment, the depressions may be formed to extend between two portions. The depressions 250, 251, 252 are selectively provided with optimal usage of material. The depressions 250, 251, 252 are configured to have a profile substantially similar to the corresponding profile of the rear member 210/ 211 thereat.
[00061] In one embodiment, the plurality of portion 206, 207, 208 (partitioned along imaginary lines) are integrally formed to result in the first sub-member 230 and said second sub-member 240, as illustrated. This provides ease of manufacturing and co-joining.
[00062] In another embodiment, the plurality of portions 206, 207, 208 are formed as discrete parts for each of the first sub-member 230 and the second sub-member 240. This enables in choosing each portion with a required thickness, stiffness or other structural parameters.
[00063] In one embodiment, the first depression 250 is configured to have a wider profile at front and a receding profile when moving in a direction towards the mid-portion, referred to a pre-determined profile PP1. In one embodiment, the second depression 251 is formed in the mid-portion and is comprising shape of a bend that the second rear member 211 undergoes, the profile is referred to as PP2. In the depicted embodiment, the third depression 252 is having a rectangular profile, referred to as a pre-determined profile PP3. Thus, the depressions 250, 251, 252 that are selectively provided on the second sub-member 240 to enable in ease of alignment of the second sub-member 240 with the first sub-member 230. In one embodiment, the plurality of depressions 250, 251, 252 are projecting inward (when viewed in longitudinal direction F-R). Each of the plurality of depressions 250, 251, 252 are configured with a pre-determined profile PP1, PP2, PP3. Each of the depression 250, 251, or 252 is provided a pre-determined depth D (shown in Fig. 2 (d)). Each depression can be configured to have a different depth depending on structural requirements. In case of the mis-alignment, the profile of the depressions configured to be fit at selected location would act as interfering parts due to mis-alignment whereby welding of mis-aligned parts is avoided.
[00064] Further, as shown in Fig. 2 (d), the dotted lines at the second sub-member shows the profile thereof at a region away from the depression 251 (for the sake of explanation, the second depression 251 is considered and the same is applicable to all depressions). During stamping of the second sub-member 240, the depression 251 is also formed. Further, at the depression 251, the surface is inward when compared to rest of the second sub-member 240. Thus, in effect, the second sub-member is provided with structure disposed in two planes i.e. one plane along depression 251 and one plane along the rest of the second sub-member 240. Thus, the second sub-member 240 disposed with the depression 251 in two planar regions provides structural stiffness to the second rear member 211 and the rear structure 200. Further, the first sub-member 230 and the second sub-member 240 can be selected from any known metals. For example, even two different metals or dissimilar materials can be used.
[00065] In one embodiment, as shown in Fig. 2 (e), the first sub-member 230 is having a C-shaped section with an opening that is covered by the second sub-member 240. The first sub-member 230 is having a first inner width W11 and the first inner width is subject to vary along length of the second rear member 211. The corresponding first depression 251 is provided with a third width W3. The plurality of depressions 250, 251, 252 are each provided with the third width W3 at the pre-determined portion. In one embodiment, the third width W3 of the depression is substantially equal to the corresponding first inner width W11 thereat (at the corresponding pre-determined portion of the first sub-member 230). Thus, the depressions 250, 251, 252, in addition to providing structural stiffness act as locators for aligning and conjoining the first sub-member 230 and the second sub-member 240.
[00066] Fig. 2 (f) illustrates a top view of a frame assembly, in accordance with an embodiment of the present subject matter. The region AB, shown in dotted lined, is one of the critical regions of the frame assembly 200. Transfer of loads between main tube 107 and the rear structure 205, mounting for power unit, which is one of heavy components, supporting utility box, supporting the seat assembly is happening at this region AB. Fig. 2 (g) is an enlarged view of a region of the frame assembly 200, in accordance with an embodiment of the present subject matter. The second side member 211 is provided with a front end 225, which is having a first lateral width LW1. In one embodiment, the first lateral width LW1 is kept larger at the front end 225 when compared to a portion away from the front end 225.
[00067] Fig. 2 (h) illustrates an enlarged side view of a front end of a rear member, in accordance with an embodiment of the present subject matter. Fig. 2 (i) illustrates a sectional view of the frame assembly taken along axis B-B’, in accordance with an embodiment as illustrated in Fig. 2 (f). At the front end 225, a high load region R1 is defined, and the front end 225 with the high load region R1 is connected to the first bridge member 215. The first bridge member 215 is provided with a side-stand bracket 280, which is capable of rotatably supporting the side-stand. Moreover, at the high load region R1 a bush member 275 is provided to mount a connecting link 290. The high load region R1 comprises a larger area when compared to a similar length of section taken at other regions of the side member 210/211. In one embodiment, the high load region R1 is configured to have a trapezoidal profile. In another embodiment, the high load region R1 may be configured to a rectangular or any other known geometrical profile. The first sub-member 230 and the second sub-member 240 enable in achieving the desired high load region R1 during the manufacturing process of stamping itself. Moreover, such varying profile can be configured with ease as per the present invention. Further, a first depression 250 is provided in proximity to this high load region R1 to take advantage of the profile in order to achiever alignment.
[00068] The first rear member 210 and the second rear member 211 are provided with a bush member 275. The bush member 275 is placed in between the first sub-member 230 and the second sub-member 240. In one embodiment, end of the bush member 275 are welded to the first sub-member 230 and the second sub-member 240. In one implementation, the bush member 275 is a cylindrical structure with hollow center. C shaped bracket and outer bracket in the region are for mounting toggle suspension at the bush member 275, which is a connecting member 290 (shown in Fig. 2 (b)) like a toggle link. The bush member 275 prevents any lateral buckling of first sub-member 230 and the second sub-member 240, which might otherwise occur due to tightening force applied for mounting the connecting link 290 for swingably mounting the power unit 135 (as shown in Fig. 2 (b)).
[00069] Further, as shown in Fig. 2 (i), the section taken along the axis B-B’, illustrates the front end 225 of the rear members 210/ 211 having a first sectional profile SP1 profile, as seen along an axis of rear member 210/211. In one embodiment, the first sectional profile SP1 taken along an axis orthogonal to the axis of the rear member is rectangular. The first sectional profile SP1 has a first height H1 and a first lateral width LW1. In one embodiment, the first height H1 is taken in up-down direction UW-DW. The first height H1 is larger than the first lateral width LW1. In one embodiment, the first height H1, taken in up-down direction UW-DW, is substantially greater than a second height H2 (shown in Fig. 2 (b)) taken at a region away from the front end 225. The configuration of the rectangular area provides a larger sectional region, which is stiffer to withstand various loads acting thereon. For example, the front end 225 of the rear structure 205 receives load/vibrations from the power unit, from the main tube 107 and from other parts that are supported thereat.
[00070] Fig 2 (j) illustrates another schematic isometric sectional view of the rear structure taken along axis B-B’, in accordance with an embodiment. The front end 225 of the second rear member 211 is provided with the larger high load region R1 (as shown in Fig. 2 (h)). An inner surface IS of the first sub-member 230 also has the larger high load region R1 at the front end 225. End surfaces of a connecting link-sleeve 291 abut with the inner surface IS, which further acts as a rigid support to take loads from the connecting link 290. The connecting link-sleeve 291 is configured to cover at least a portion of a mounting axle 292. The mounting axle 292 extends between the bush members 275 of the first rear member 210 and the second rear member 211. Around the mounting axle 292 and between the rear member 210, 211 a cushioning member 293 is provided. The cushioning member 290 is provided with an inner sleeve 294I and an outer 294O.
[00071] Fig. 3 (a) and Fig. 3 (b) depicts perspective view and a side sectional-view, respectively, of a motor vehicle, in accordance with another embodiment of the present subject matter. As per the present invention the geometric dimensional accuracy of the frame assembly increases thereby enabling better finish of parts, precise packaging of parts etc. As per an aspect of the present invention, owing to the present configuration of the frame assembly, the frame assembly is now capable of receiving alternate fuel storage units like metal hybrid canisters which cannot tolerate tolerance variations as in known arts. The motor vehicle as explained comprises a rear structure 205 as discussed in above embodiments. Further, the motor vehicle comprises one or more metal hybrid canisters 301, 302 supported on the rear structure 205 and under a seat assembly 155. The metal hybrid canisters 301, 302 form a first layer. A fuel cell stack 303 is disposed as a second layer below the first layer. The fuel cell stack 303 is supported by the rear structure 205. The fuel cell stack 303 has a pressure regulator, a blower, a solenoid valve, a proportional valve and two heaters. A motor controller is disposed on a rear side of the fuel cell stack 303. A fuel cell controller 306 controls operation of the fuel cell stack 303. The fuel cell controller 306 is also provided below the floor-board. A fuel cell controller 306 works with a fuel cell buck converter or booster, which controls the voltage. A fuel exhaust pipe from the fuel cell stack 303 is controlled by the proportional valve to avoid fuel starvation. An oxidant exhaust manifold is open to the atmosphere at a rear side of the motor vehicle. The metal hybrid canisters 301, 302 are connected through an inter-connector tube to deliver required flow rate to the fuel cell stack 303. A pressure regulator controls pressure of flow from the metal hybrid canisters 301, 302. A solenoid valve and a proportional valve of the fuel cell stack 303 are electronically controlled by the fuel cell controller 306.
[00072] A battery pack 304 is disposed at a step-through portion and below a floorboard. The battery pack 304 is supported by a main tube of a front structure 101. The rear wheel is provided with an electric hub motor 305, which can act as one of the prime movers. The battery pack 304 is electrically connected to the electric hub motor 305.
[00073] While Fig. 4 (a), Fig. 4 (b) & Fig. 4 (c) illustrates a top view, an isometric view & a schematic side sectional-view, respectively, of a portion of a motor vehicle, in accordance with yet another embodiment of the present subject matter. The motor vehicle 400 comprises a front structure 401 and a rear structure 205. In the present subject matter, the front structure 401 is a monocoque structure, wherein one or more front side members 402, 403 form the structural members and also style parts. The front structure 401 comprises a floorboard 404. The floorboard 404 comprises a primary storage 406 and a second storage 407 with openings upwards and the storages 406, 407 are covered by a floor-cover 405. In one embodiment, the motor vehicle 400 is electric or hybrid vehicle. Owing to the design of the high stress and high load region AB, the frame structure is now rendered capable of withstanding the additional load arising out of the disposition of the storage 406, 407 as per this embodiment.
[00074] In one embodiment, the first storage 406 and the secondary storage 407 are configured to store a primary battery pack 408 and a secondary pack 409. The primary battery pack 408 and the secondary battery pack 409 are electrically connected to an electric motor (not shown), which is disposed on a swing arm (not shown) or is hub mounted to rear wheel. The primary storage 406 is preferred for storing the primary battery pack 408 as it is away from a front portion of motor vehicle 400. The secondary storage 407 can be configured to be used as article storage space. The rear structure 205 with one or more rear members 211 is connected to the front structure 401.
[00075] certain features of the claimed subject matter have been illustrated and described herein, many modifications, substitutions, changes, and equivalents will now occur to those skilled in the art. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes that fall within the true spirit of the claimed subject matter.


List of reference signs:
100/300 vehicle
101/401 front structure
106 head tube
107 main tube
130 front wheel
131 front suspension system
133 rear wheel
134 rear suspension system
150 handlebar assembly
151 step-through portion
155 seat assembly
170A front panel
170B leg shield
170C rear panel assembly
200 frame assembly
205 rear structure
206 front-portion
207 mid-portion
208 rear-portion
210 first rear member
211 second rear member
215/216/217/218/219 bridge member
220A/220B floor frame
225 front end
230 first sub-member
230A/230B end region
240 second sub-member
250/251/252 depression
260 weld joint
275 bush member
280 side-stand bracket
290 connecting link
291 connecting link-sleeve
292 mounting axle
293 cushioning member
294I inner sleeve
294O outer sleeve
A1 first cross-sectional area
A2 second cross-sectional area
D depth
H1 first height
H2 second height
IFS inward facing side
IS inner surface
OFS outer facing side
LW1 first lateral width
PP1/PP2/PP3 pre-determined profile
SP1 sectional profile
R1 region
W1 first outer width
W11 first inner width
W2 second outer width
W3 third width
301/302 metal hybrid tank
303 fuel cell stack
304 battery pack
305 electric hub motor
306 fuel cell controller
402/403 front side member
404 floorboard
405 floor-cover
406/407 storage
408/409 battery pack