Description:FIELD OF THE INVENTION

[1] The present disclosure generally relates to a saddle-type vehicle. More particularly, the present disclosure relates to the frame structure of a saddle-type vehicle.

BACKGROUND

[2] In a saddle-type vehicle, for example an internal combustion engine (ICE) scooter, the frame structure will have a single main tube coupled to a steering handle through a headtube on one end. Typically, the other end of the single main tube is either split into two or will extend as a single tube. The single main tube may extend up to a swing arm pivot region or may extend to the rear end of the scooter.

[3] In an existing frame structure, a single main tube, i.e. tube (205A) is coupled to the steering handle (not shown) through a headtube (210A) on one end while the other end is split into two and extends up to swing arm pivot region as illustrated in Figure 2A. In another existing frame structure, the single main tube (205B) is coupled to the steering handle through the headtube (210B) on one end while the other end is split into two and extends till the rear half of the frame as illustrated in Figure 2B.

[4] The frame structures illustrated in Figure 2A and Figure 2B provide lower storage volume. Moreover, the frame structures illustrated in Figure 2A and Figure 2B do not provide adequate space for battery. Furthermore, the single main tube frame structure do not provide adequate stiffness to shorter swing arms.

SUMMARY

[5] This summary is provided to introduce a selection of concepts, in a simplified format, that is further described in the detailed description of the invention. This summary is neither intended to identify key or essential inventive concepts of the invention and nor is it intended for determining the scope of the invention.

[6] The main objective of the present disclosure is to provide a new frame structure for providing a higher storage space and higher battery volume in a saddle-type vehicle.

[7] In an embodiment of the present disclosure, a frame structure for a saddle-type vehicle is disclosed. The frame structure includes a head tube for mounting a steering handle. The frame structure includes a pair of main tubes coupled to the head tube and arranged in a fork configuration. Each main tube includes a front portion, a mid-horizontal portion, and a rear portion. The frame structure includes a pair of side tubes. Each side tube includes a front end and a rear end coupled respectively to the front portion and the rear portion of the corresponding main tube. The frame structure includes a pair of rear tubes coupled to the pair of main tubes respectively, wherein the head tube, the pair of main tubes, the pair of side tubes, and the pair of rear tubes extend along a longitudinal direction of the saddle-type vehicle.

[8] To further clarify the advantages and features of the present invention, a more particular description of the invention will be rendered by reference to specific embodiments thereof, which are illustrated in the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. The invention will be described and explained with additional specificity and detail with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[9] These and other features, aspects, and advantages of the present invention will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:

[10] Figure 1 illustrates a perspective side view of a two-wheeler vehicle having, according to an embodiment of the present disclosure;

[11] Figure 2A and Figure 2B illustrate a perspective view of a frame structure in a saddle-type vehicle, in accordance with a prior art;

[12] Figure 3 illustrates a perspective view of a frame structure of a saddle-type vehicle, according to an embodiment of the present disclosure;

[13] Figure 4 illustrates a perspective view of the frame structure of the saddle-type vehicle, according to an embodiment of the present disclosure;

[14] Figure 5 illustrates a perspective top view of a frame structure, according to an embodiment of the present disclosure;

[15] Figure 6A illustrates a perspective view of an interface of a main tube to head tube in the frame structure, according to an embodiment of the present disclosure;

[16] Figure 6B and Figure 6C illustrate a perspective view of a front mounting bracket in a saddle-type vehicle, according to an embodiment of the present disclosure;

[17] Figure 7A and Figure 7B illustrate a perspective view of a bracket for side stand mounting in the frame structure, according to an embodiment of the present disclosure;

[18] Figure 8A and Figure 8B illustrate a perspective view of a swing arm pivot assembly in the frame structure, according to an embodiment of the present disclosure;

[19] Figure 9A, Figure 9B, and Figure 9C illustrate a perspective view of an interface of a main tube to rear tube in the frame structure, according to an embodiment of the present disclosure;

[20] Figure 10A illustrates a perspective view of a storage space in the saddle-type vehicle, according to an embodiment of the present disclosure; and

[21] Figure 10B illustrates a perspective view of battery space in the saddle-type vehicle, according to an embodiment of the present disclosure.

[22] Further, skilled artisans will appreciate that elements in the drawings are illustrated for simplicity and may not have necessarily been drawn to scale. For example, the flow charts illustrate the method in terms of the most prominent steps involved to help to improve understanding of aspects of the present invention. Furthermore, in terms of the construction of vehicle, one or more components of the vehicle may have been represented in the drawings by conventional symbols, and the drawings may show only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the drawings with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.

DETAILED DESCRIPTION OF FIGURES

[23] For the purpose of promoting an understanding of the principles of the present disclosure, reference will now be made to the various embodiments and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the present disclosure is thereby intended, such alterations and further modifications in the illustrated system, and such further applications of the principles of the present disclosure as illustrated therein being contemplated as would normally occur to one skilled in the art to which the present disclosure relates.

[24] It will be understood by those skilled in the art that the foregoing general description and the following detailed description are explanatory of the present disclosure and are not intended to be restrictive thereof.

[25] Whether or not a certain feature or element was limited to being used only once, it may still be referred to as “one or more features” or “one or more elements” or “at least one feature” or “at least one element.” Furthermore, the use of the terms “one or more” or “at least one” feature or element do not preclude there being none of that feature or element, unless otherwise specified by limiting language including, but not limited to, “there needs to be one or more…” or “one or more elements is required.”

[26] Reference is made herein to some “embodiments.” It should be understood that an embodiment is an example of a possible implementation of any features and/or elements of the present disclosure. Some embodiments have been described for the purpose of explaining one or more of the potential ways in which the specific features and/or elements of the proposed disclosure fulfil the requirements of uniqueness, utility, and non-obviousness.

[27] Use of the phrases and/or terms including, but not limited to, “a first embodiment,” “a further embodiment,” “an alternate embodiment,” “one embodiment,” “an embodiment,” “multiple embodiments,” “some embodiments,” “other embodiments,” “further embodiment”, “furthermore embodiment”, “additional embodiment” or other variants thereof do not necessarily refer to the same embodiments. Unless otherwise specified, one or more particular features and/or elements described in connection with one or more embodiments may be found in one embodiment, or may be found in more than one embodiment, or may be found in all embodiments, or may be found in no embodiments. Although one or more features and/or elements may be described herein in the context of only a single embodiment, or in the context of more than one embodiment, or in the context of all embodiments, the features and/or elements may instead be provided separately or in any appropriate combination or not at all. Conversely, any features and/or elements described in the context of separate embodiments may alternatively be realized as existing together in the context of a single embodiment.

[28] Any particular and all details set forth herein are used in the context of some embodiments and therefore should not necessarily be taken as limiting factors to the proposed disclosure.

[29] The terms “comprises”, “comprising”, or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process or method that comprises a list of steps does not include only those steps but may include other steps not expressly listed or inherent to such process or method. Similarly, one or more devices or sub-systems or elements or structures or components proceeded by “comprises... a” does not, without more constraints, preclude the existence of other devices or other sub-systems or other elements or other structures or other components or additional devices or additional sub-systems or additional elements or additional structures or additional components.

[30] Embodiments of the present disclosure will be described below in detail with reference to the accompanying drawings.

[31] For the sake of clarity, the first digit of a reference numeral of each component of the present disclosure is indicative of the Figure number, in which the corresponding component is shown. For example, reference numerals starting with digit “1” are shown at least in Figure 1. Similarly, reference numerals starting with digit “2” are shown at least in Figure 2.

[32] An Electric Vehicle (EV) or a battery powered vehicle including, and not limited to two-wheelers such as scooters, mopeds, motorbikes/motorcycles; three-wheelers such as auto-rickshaws, four-wheelers such as cars and other Light Commercial Vehicles (LCVs) and Heavy Commercial Vehicles (HCVs) primarily work on the principle of driving an electric motor using the power from the batteries provided in the EV. Furthermore, the electric vehicle may have at least one wheel which is electrically powered to traverse such a vehicle. The term ‘wheel’ may be referred to any ground-engaging member which allows traversal of the electric vehicle over a path. The types of EVs include Battery Electric Vehicle (BEV), Hybrid Electric Vehicle (HEV) and Range Extended Electric Vehicle. However, the subsequent paragraphs pertain to the different elements of a Battery Electric Vehicle (BEV).

[33] In construction, as illustrated in Figure 1, an EV (10) typically comprises a battery or battery pack (12) enclosed within a battery casing and includes a Battery Management System (BMS), an on-board charger (14), a Motor Controller Unit (MCU), an electric motor (16) and a transmission system (18). The primary function of the above-mentioned elements is detailed in the subsequent paragraphs: The battery of an EV (10) (also known as Electric Vehicle Battery (EVB) or traction battery) is re-chargeable in nature and is the primary source of energy required for the operation of the EV, wherein the battery (12) is typically charged using the electric current taken from the grid through a charging infrastructure (20). The battery may be charged using Alternating Current (AC) or Direct Current (DC), wherein in case of AC input, the on-board charger (14) converts the AC signal to DC signal after which the DC signal is transmitted to the battery via the BMS. However, in case of DC charging, the on-board charger (14) is bypassed, and the current is transmitted directly to the battery via the BMS.

[34] The battery (12) is made up of a plurality of cells which are grouped into a plurality of modules in a manner in which the temperature difference between the cells does not exceed 5 degrees Celsius. The terms “battery”, “cell”, and “battery cell” may be used interchangeably and may refer to any of a variety of different rechargeable cell compositions and configurations including, but not limited to, lithium-ion (e.g., lithium iron phosphate, lithium cobalt oxide, other lithium metal oxides, etc.), lithium-ion polymer, nickel metal hydride, nickel cadmium, nickel hydrogen, nickel-zinc, silver zinc, or other battery type/configuration. The term “battery pack” as used herein may be referred to multiple individual batteries enclosed within a single structure or multi-piece structure. The individual batteries may be electrically interconnected to achieve a desired voltage and capacity for a desired application. The Battery Management System (BMS) is an electronic system whose primary function is to ensure that the battery (12) is operating safely and efficiently. The BMS continuously monitors different parameters of the battery such as temperature, voltage, current and so on, and communicates these parameters to the Electronic Control Unit (ECU) and the Motor Controller Unit (MCU) in the EV using a plurality of protocols including and not limited to Controller Area Network (CAN) bus protocol which facilitates the communication between the ECU/MCU and other peripheral elements of the EV (10) without the requirement of a host computer.

[35] The MCU primarily controls/regulates the operation of the electric motor based on the signal transmitted from the vehicle battery, wherein the primary functions of the MCU include starting of the electric motor (16), stopping the electric motor (16), controlling the speed of the electric motor (16), enabling the vehicle to move in the reverse direction and protect the electric motor (16) from premature wear and tear. The primary function of the electric motor (16) is to convert electrical energy into mechanical energy, wherein the converted mechanical energy is subsequently transferred to the transmission system of the EV to facilitate movement of the EV. Additionally, the electric motor (16) also acts as a generator during regenerative braking (i.e., kinetic energy generated during vehicle braking/deceleration is converted into potential energy and stored in the battery of the EV). The types of motors generally employed in EVs include, but are not limited to DC series motor, Brushless DC motor (also known as BLDC motors), Permanent Magnet Synchronous Motor (PMSM), Three Phase AC Induction Motors and Switched Reluctance Motors (SRM).

[36] The transmission system (18) of the EV (10) facilitates the transfer of the generated mechanical energy by the electric motor (16) to the wheels (22a,22b) of the EV. Generally, the transmission systems (18) used in EVs include single speed transmission system and multi-speed (i.e., two-speed) transmission system, wherein the single speed transmission system comprises a single gear pair whereby the EV is maintained at a constant speed. However, the multi-speed/two-speed transmission system comprises a compound planetary gear system with a double pinion planetary gear set and a single pinion planetary gear set thereby resulting in two different gear ratios which facilitates higher torque and vehicle speed.

[37] In one embodiment, all data pertaining to the EV (10) and/or charging infrastructure (20) are collected and processed using a remote server (known as cloud) (24), wherein the processed data is indicated to the rider/driver of the EV (10) through a display unit present in the dashboard (26) of the EV (10). In an embodiment, the display unit may be an interactive display unit. In another embodiment, the display unit may be a non-interactive display unit.

[38] Embodiments of the present disclosure provide a frame structure of a saddle-type vehicle, for example, the electric vehicle (10). The saddle-type vehicle (10) includes a steering handle (30) mounted on a headtube.

[39] Figure 3 illustrates a perspective view of a frame structure (300) of a saddle-type vehicle, according to an embodiment of the present disclosure. The frame structure (300) includes a head tube (310) for mounting a steering handle. The frame structure (300) includes a pair of main tubes (305a, 305b) coupled to the head tube (310) and arranged in a fork configuration. The pair of main tubes (305a, 305b) can also be considered to be arranged in an inverted “V” configuration. The pair of main tubes (305a, 305b) is interchangeably referred to as main tube (305) in the present disclosure.

[40] An interface of the pair of main tubes (305a, 305b) to the headtube (310) is illustrated in Figure 6A. The axis (Z-Z’) of the steering axis of the vehicle and the pair of main tubes (305a, 305b) are at an acute angle as illustrated in Figure 6A. A headstock gusset (605) is integrated to the interface of the main tube (305) and the headtube (310) as illustrated in Figure 6A.

[41] Figure 6B shows the axis (Y-Y’) of the center plane of the frame structure (300) and the pair of main tubes (305a, 305b) form an acute angle. The pair of main tubes (305a, 305b) is welded all round on the headtube (310). The width of the pair of main tubes (305a, 305b) is decided as per the volume of the electrical modules, battery, and storage box volumes.

[42] One way to consider the frame structure (300) is as a main tube (305) joined to a rear tube. Further, three parts or portions can be joined to form the main tube. In one embodiment, the main tubes (305a, 305b) include a front portion (AA’- BB’), a mid-horizontal portion (BB’- CC’), and a rear portion (CC’- DD') as illustrated in Figure 4.

[43] Referring to Figure 3, the frame structure (300) includes a pair of side tubes (315a, 315b). Each side tube (315a, 315b) includes a front end (320a, 320b) and a rear end (325a, 325b) coupled respectively to the front portion (AA’-BB’) and the rear portion (CC’-DD') of the corresponding main tube (305a, 305b).

[44] The frame structure (300) includes a pair of rear tubes (330a, 330b) coupled to the pair of main tubes respectively (305a, 305b). The pair of rear tubes (330a, 330b) is interchangeably referred to as rear tube (330) in the present disclosure. The head tube (310), the pair of main tubes (305a, 305b), the pair of side tubes (315a, 315b), and the pair of rear tubes (330a, 330b) extend along a longitudinal direction (L-L’) of the saddle-type vehicle as illustrated in Figure 4. Each rear portion of the pair of main tubes (305a, 305b) has a first diameter less than a second diameter of each rear tube of the pair of rear tubes (330a, 330b) and is welded together.

[45] In one embodiment, three cross tubes are joined to the frame structure (300) in between the main tube (305) and rear tube (330). Referring to Figure 5, the frame structure (300) includes a first cross tube, i.e., a front cross tube (505) coupled to the respective front portions (AA’- BB’) of the pair of main tubes (305a, 305b). The front cross tube (505) is also referred to as front battery cross tube. The front cross tube (505) is welded to the pair of main tubes (305a, 305b). The functionality of the front cross tube (505) or the front battery cross tube is to mount battery from front. Further, the front cross tube (505) adds stiffness to the frame structure (300).

[46] The frame structure (300) includes a second cross tube, i.e., a mid-cross tube (510). The mid-cross tube (510) is coupled to the respective rear portion (CC’- DD') of the pair of main tubes (305a, 305b). The second cross tube or the mid-cross tube is also referred to as swing arm pivot cross tube. The mid-cross tube (510) is welded on the swing arm pivot mounts. The swing art pivot assembly is further explained in conjunction with Figure 8A and Figure 8B. The functionality of the mid-cross tube (510) is mounting the rear battery mounts and adding stiffness to the frame structure (300).

[47] Further, the frame structure (300) includes a third cross tube, i.e., the rear cross tube (515). The rear cross tube (515) is coupled to the pair of rear tubes (330a, 330b). The rear cross tube (515) is welded on the rear tubes (330a, 330b). The functionality of the rear cross tube (515) is to mount the seat lock, storage box mount and rear shock top mounts. It is to be noted that the front cross tube (505), the mid-cross tube (510), and the rear cross tube (515) extend along a lateral direction (H-H’) of the saddle-type vehicle.

[48] The frame structure (300) includes multiple brackets for mounting various parts and accessories. In an embodiment, the frame structure (300) includes a front mounting bracket (610) coupled to the respective front portions of the pair of main tubes (305a, 305b). The front mounting bracket (610) is illustrated in Figure 6B and Figure 6C. Further, in one embodiment, the front mounting bracket (610) can be coupled to the front cross tube (505) as illustrated in in Figure 6B and Figure 6C.

[49] The frame structure (300) includes a substantially U-shaped cross tube (335) coupled to the respective rear portions of the pair of main tubes (305a, 305b). The substantially U-shaped cross tube (335), the respective rear portions (CC’-DD') of the pair of main tubes (305a, 305b), and the pair of rear tubes (330a, 330b) together form a storage space (520) as illustrated in Figure 5. The pair of rear tubes (330a, 330b) is the portion (DD’- EE’) as illustrated in Figure 4 and Figure 5. The frame structure (300) includes a rear mounting bracket (340) coupled to the substantially U-shaped cross tube (335) as illustrated in Figure 3.

[50] Another mounting bracket in the frame structure (300) is a side mounting bracket (705) for mounting a side stand. The frame structure (300) includes a side mounting bracket (705) coupled to one side tube of the pair of side tubes (315a, 315b), for example, side tube (315), and the mid-horizontal portion (BB’- CC’) of the corresponding main tube as illustrated in Figure 7A and Figure 7B.

[51] It is to be noted that each side tube (315) is substantially parallel to the mid-horizonal portion of the corresponding main tube in order to maximize the battery volume. The side tubes (315a, 315b) are welded to the main tubes (305a, 305b). The functionality of the side tubes is to add stiffness, majorly vertical stiffness, to the whole frame structure (300). Further, it provides strength for the side stand load cases. Furthermore, it is used for floorboard battery mounting.

[52] One of the crucial components of a saddle type vehicle is the swing arm pivot mount sub assembly. The swing arm acts as a load transfer linkage between rear wheel and the frame through a rear shock absorber. Figure 8A and Figure 8B illustrate a swing arm assembly. The frame structure (300) includes a swing arm pivot mount sub assembly (805) coupled to the respective rear portions of the pair of main tubes (305a, 305b). The swing arm pivot mount sub assembly (805) includes a pair of swing arm pivot gussets (810a, 810b) connected to each other through a swing arm pivot cross tube (815).

[53] The pair of swing arm pivot gussets (810a, 810b) have a substantially U-shaped cross section (820) and partially encloses the respective rear portions of the pair of main tubes as illustrated in Figure 8B. It is to be noted that the mid-cross tube (510) of Figure 5 and the swing arm pivot cross tube (815) are same and have been interchangeably referred in the present disclosure. The swing arm pivot mount sub assembly (805) is formed with sheet metal components which are welded together to form a sub assembly having a plurality of parts. The sub assembly is then welded on the respective rear portions of the pair of main tubes (305a, 305b) and the front portion of the rear tubes (330a, 330b).

[54] Figure 9A, Figure 9B, and Figure 9C illustrate a perspective view of an interface of a main tube (305) to rear tube (330) in the frame structure (300), according to an embodiment of the present disclosure. The interface (905) of the rear tubes (330a, 330b) and the main tubes (305a, 305b) are at the swing arm pivot region. The tubes are inserted inside each other and then welded all round, shown in the cross section in Figure 9B and Figure 9C. The swing arm pivot assembly (805) is added parallel to the joining location (910) as this is the area where maximum stresses are generated and hence the load is evenly distributed instead of concentrating at the joining location (910).

[55] Figure 10A illustrates a perspective view of a storage space in the saddle-type vehicle, according to an embodiment of the present disclosure. The storage box cross tube (1010) is welded on the main tubes (305a, 305b) with a sheet metal wrap. The storage box cross tube (1010) is also referred to as the substantially U-shaped cross tube (335). The storage space (1015) in the storage box (1005) provides a higher volume than conventional scooter storage spaces.

[56] Figure 10B illustrates a perspective view of battery space in the saddle-type vehicle, according to an embodiment of the present disclosure.

[57] The front cross tube (505) also referred to as front battery cross tube is used to mount battery (1020) from the front region. The mid-cross tube (510) also referred to as swing arm pivot cross tube is used for mounting the rear battery mounts. The front cross tube (505), the mid-cross tube (510), and the side tubes (315a, 315b) provide space to accommodate higher batter size.

[58] There are various advantages of the frame structure (300). The frame structure (300) provides higher storage capacity and higher battery size without changing the overall vehicle dimensions and volume. The frame structure (300) along with the cross tubes and the swing arm pivot mount sub assembly (805) provides higher stiffness than other existing saddle-type vehicles. Further, the fork arrangement or inverted “V” shaped arrangement of the main tube in the frame structure allows compact placement of major electrical modules in the electric scooter.

[59] In this application, unless specifically stated otherwise, the use of the singular includes the plural and the use of “or” means “and/or.” Furthermore, use of the terms “including” or “having” is not limiting. Any range described herein will be understood to include the endpoints and all values between the endpoints. Features of the disclosed embodiments may be combined, rearranged, omitted, etc., within the scope of the invention to produce additional embodiments. Furthermore, certain features may sometimes be used to advantage without a corresponding use of other features.

[60] List of reference numerals:
Components Reference numerals
Frame structure 300
Head tube 310
Main tubes 305a, 305b
Side tubes 315a, 315b
Rear tubes 330a, 330b
Front cross tube 505
Mid-cross tube 510
Rear cross tube 515
U-shaped cross tube 335
Front mounting bracket 610
Rear mounting bracket 340
Side mounting bracket 705
Swing arm pivot mount sub assembly 805
Swing arm pivot gussets 810a, 810b
Swing arm pivot cross tube 815
Headstock gusset 605
Storage box 1005
Battery 1015
Main tube 305
Rear tube 330
Side tube 315 , Claims:1. A frame structure (300) for a saddle-type vehicle (10), the frame structure (300) comprising:
a head tube (310) for mounting a steering handle (30);
a pair of main tubes (305a, 305b) coupled to the head tube (310) and arranged in a fork configuration, wherein each main tube (305a, 305b) comprises a front portion (AA’- BB’), a mid-horizontal portion (BB’- CC’), and a rear portion (CC’- DD');
a pair of side tubes (315a, 315b), wherein each side tube (315a, 315b), comprises a front end (320a, 320b) and a rear end (325a, 325b) coupled respectively to the front portion (AA’- BB’) and the rear portion (CC’- DD') of the corresponding main tube (305a, 305b); and
a pair of rear tubes (330a, 330b) coupled to the pair of main tubes respectively (305a, 305b), wherein the head tube (310), the pair of main tubes (305a, 305b), the pair of side tubes (315a, 315b), and the pair of rear tubes (330a, 330b) extend along a longitudinal direction (L-L’) of the saddle-type vehicle (10).

2. The frame structure (300) as claimed in claim 1, comprising:
a front cross tube (505) coupled to the respective front portions (AA’- BB’) of the pair of main tubes (305a, 305b);
a mid-cross tube (510) coupled to the respective rear portion (CC’- DD') of the pair of main tubes (305a, 305b); and
a rear cross tube (515) coupled to the pair of rear tubes (330a, 330b), wherein the front cross tube (505), the mid-cross tube (510), and the rear cross tube (515) extend along a lateral direction (H-H’) of the saddle-type vehicle (10).

3. The frame structure (300) as claimed in claim 2, comprising a front mounting bracket (610) coupled to the respective front portions (AA’- BB’) of the pair of main tubes (305a, 305b).

4. The frame structure (300) as claimed in claim 3, wherein the front mounting bracket (610) is coupled to the front cross tube (505).

5. The frame structure (300) as claimed in claim 1, comprising:
a substantially U-shaped cross tube (335) coupled to the respective rear portions (CC’- DD') of the pair of main tubes (305a, 305b), wherein the substantially U-shaped cross tube (335), the respective rear portions (CC’-DD') of the pair of main tubes (305a, 305b), and the pair of rear tubes (330a, 330b) together form a storage space (520).

6. The frame structure (300) as claimed in claim 5, comprising a rear mounting bracket (340) coupled to the substantially U-shaped cross tube (335).

7. The frame structure (300) as claimed in claim 1, comprising a side mounting bracket (705) coupled to one side tube of the pair of side tubes (315a, 315b) and the mid-horizontal portion (BB’- CC’) of the corresponding main tube (305a, 305b), wherein the side mounting bracket (705) is configured to mount a side stand.

8. The frame structure (300) as claimed in claim 1, wherein each side tube (315a, 315b) is substantially parallel to the mid-horizonal portion (BB’- CC’) of the corresponding main tube (305a, 305b).

9. The frame structure (300) as claimed in claim 1, comprising a swing arm pivot mount sub assembly (805) coupled to the respective rear portions (CC’- DD') of the pair of main tubes (305a, 305b), wherein the swing arm pivot mount sub assembly (805) comprises a pair of swing arm pivot gussets (810a, 810b) connected to each other through a swing arm pivot cross tube (815).

10. The frame structure (300) as claimed in claim 9, wherein the pair of swing arm pivot gussets (810a, 810b) have a substantially U-shaped cross section and partially encloses the respective rear portions (CC’- DD') of the pair of main tubes (305a, 305b).

11. The frame structure (300) as claimed in claim 1, wherein each rear portion (CC’- DD') of the pair of main tubes (305a, 305b) has a first diameter less than a second diameter of each rear tube of the pair of rear tubes (330a, 330b).