The present disclosure relates to a rear structure of a vehicle. In particular, the present disclosure relates to a quarter area of the rear structure of the vehicle in order to reduce local stresses developed across the area so as to enhance stiffness of the rear structure of the vehicle.
BACKGROUND
[0002] In recent times, the applicability of a vehicle, say a personal car or a commercial car, is not limited for daily commuting purposes. On the contrary, these are widely and extensively used for long drives, short trips, or even vacations. Therefore, in order to accommodate fellow passengers in a vehicle along with their luggage, the vehicles are designed with sufficient boot space. But during loading conditions, a quarter area present in a backdoor opening region of the vehicle experiences stresses thus gradually leading to deformation of an overall rear structure of the vehicle.
[0003] The quarter area comprises of an extension quarter inner panel and an extension side body outer panel. Typically, in order to combat with such stresses, the extension quarter inner panel of the vehicle is designed with two strengthening beads positioned adjacent to one another in order to provide strength to the structure. According to said present design, a first bead of the two strengthening beads, is longer than a second bead and is joined to a trim mounting bracket through spot welding.
[0004] In current design of vehicle, the gap between the extension quarter inner panel and the extension side body outer panel is large enough to achieve the desired stiffness. However, in order to increase the cabin area without increasing overall length of vehicle, the gap is required to be reduced. However, the existing structural features of the extension quarter inner panel is not able to provide desired stiffness in a newly styled vehicle. Herein, the coupling of the longer bead with the trim mounting bracket, results in an increased amount of local stiffness in the region and due to subsequent positioning of the fillet, the structural components present nearby, experiences bending along a cross section region due to less sectional modulus. As a result, the radius of curvature being the weakest region,

experiences high stresses thereby leading to deformation in the overall structure of the extension quarter inner panel under loading conditions. Moreover, the present design impairs the uniform distribution of energy throughout the overall structure.
[0005] The conventional solutions available to mitigate the above mentioned hindrances as developed due to new styling are increasing panel thickness or material grade or development of an additional reinforcement structure. But such techniques are expensive in nature and may increase the development and/or production cost.
[0006] Towards this direction, the present disclosure focuses on design of the extension quarter inner panel in order to alleviate the localized stresses thereby improving stiffness and rigidity of the structure without having to increase cost of the vehicle.
OBJECTS OF THE INVENTION
[0007] Some of the objects of the present disclosure, which at least one embodiment herein satisfy, are listed herein below.
[0008] It is an object of the present subject matter to overcome the aforementioned and other drawbacks existing in the prior art systems and methods.
[0009] It is a significant object of the present disclosure to improve local stiffness of an extension quarter inner panel of a vehicle.
[0010] It is another principal object of the present disclosure to provide strengthening structures to the extension quarter inner panel of the vehicle in order to achieve a uniform distribution of energy.
[0011] It is yet another object of the present disclosure to comply with appropriate strengthening measures of the extension quarter inner panel that can provide rigidity to the overall structure.
[0012] It is even another object of the present disclosure to propose cost effective design changes in the extension quarter inner panel of the vehicle.
[0013] These and other objects and advantages of the present subject matter will be apparent to a person skilled in the art after consideration of the following detailed description

taking into consideration with accompanied drawings in which preferred embodiments of the present subject matter are illustrated.
SUMMARY OF THE INVENTION
[0014] This summary is provided to introduce concepts related to design of an extension quarter inner panel of a vehicle in order to reduce local stresses developed across the area. The concepts are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.
[0015] According to an embodiment of a present disclosure, there is provided an extension quarter inner panel of a vehicle. The extension quarter inner panel comprises of a first surface, a second surface where the second surface is perpendicular to the first surface, a third surface extending perpendicularly from a first longitudinal side of the first surface, and a fourth surface where the first surface is joined to the second surface through the third surface in straight region and through the fourth surface in curved region of the extension quarter inner panel.
[0016] In an aspect, the extension quarter inner panel includes a first strengthening bead and a second strengthening bead lying adjacent to each other and are parallel to each other.
[0017] In an aspect, the first strengthening bead is positioned adjacent to the second surface.
[0018] In an aspect, the first strengthening bead is joined with the fourth surface through a triangular surface.
[0019] In an aspect, a fillet is provided between the second surface and the third surface and a fillet is provided between first surface and the third surface, wherein the fillet is merged with the fillet at a region just below the curved face and just before the start of the fourth surface.

[0020] In an aspect, in the extension quarter inner panel, the second surface includes an elevated step profile at curved region of the extension quarter inner panel.
[0021] In an aspect, the extension quarter inner panel comprises of a first emboss and a second emboss on a fourth surface.
[0022] In an aspect, the second emboss is formed above the first strengthening bead.
[0023] In an aspect, the triangular surface is created between the second emboss and the first strengthening bead.
[0024] To further understand the characteristics and technical contents of the present subject matter, a description relating thereto will be made with reference to the accompanying drawings. However, the drawings are illustrative only but not used to limit the scope of the present subject matter.
[0025] Various objects, features, aspects, and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawing figures in which numerals represent like components.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING(S)
[0026] It is to be noted, however, that the appended drawings illustrate only typical embodiments of the present subject matter and are therefore not to be considered for limiting of its scope, for the invention may admit to other equally effective embodiments. The detailed description is described with reference to the accompanying figures. In the figures, a reference number identifies the figure in which the reference number first appears. The same numbers are used throughout the figures to reference like features and components. Some embodiments of system or methods or structure in accordance with embodiments of the present subject matter are now described, by way of example, and with reference to the accompanying figures, in which
[0027] FIG. 1 depicts an isometric view of an extension quarter inner panel of a vehicle in accordance with an embodiment of the present disclosure;

[0028] FIG. 2 depicts a layout of the extension quarter inner panel of the vehicle highlighting the bead profile and the corresponding arrangement in accordance with an embodiment of the present disclosure;
[0029] FIG. 3 depicts the layout of the extension quarter inner panel highlighting design attribute of a flange in accordance with an embodiment of the present disclosure; and
[0030] FIG. 4 depicts complete assembly of a D-pillar region of the vehicle in accordance with an embodiment of the present disclosure.
[0031] The figures depict embodiments of the present subject matter for the purposes of illustration only. A person skilled in the art will easily recognize from the following description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.
DETAILED DESCRIPTION
[0032] The following is a detailed description of embodiments of the disclosure depicted in the accompanying drawings. The embodiments are in such detail as to clearly communicate the disclosure. However, the amount of detail offered is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure as defined by the appended claims.
[0033] While the embodiments of the disclosure are subject to various modifications and alternative forms, specific embodiment thereof have been shown by way of example in the figures and will be described below. It should be understood, however, that it is not intended to limit the disclosure to the particular forms disclosed, but on the contrary, the disclosure is to cover all modifications, equivalents, and alternative falling within the scope of the disclosure.
[0034] The terms "comprises", "comprising", or any other variations thereof used in the disclosure, are intended to cover a non-exclusive inclusion, such that a device, system, assembly that comprises a list of components does not include only those components but may include other components not expressly listed or inherent to such system, or assembly, or device. In other words, one or more elements in a system or device proceeded by

"comprises... a" does not, without more constraints, preclude the existence of other elements or additional elements in the system or device.
[0035] The present disclosure proposes a strengthening arrangement in an extension quarter inner panel of a vehicle in order to enhance rigidity of quarter area of a vehicle. Under loading conditions, the extension quarter inner panel experiences bending due to the formation of localized stresses in the regions as discussed previously. Therefore, the extension quarter inner panel needs to be redesigned in order to distribute the stresses developed thereby contributing to the robustness of the entire structure.
[0036] FIG. 1 illustrates an isometric view of the extension quarter inner panel (100) of a vehicle in accordance with an embodiment of the present disclosure. In an aspect, the structure of the extension quarter inner panel (100) can be divided into four surfaces, namely a first surface (102), a second surface (103), a third surface (104), and a fourth surface (105). The first surface (102) is joined to the second surface (103) through the third surface (104) in straight region and through the fourth surface (105) in curved region of the extension quarter inner panel (100).
[0037] In an aspect, the second surface (103) is perpendicular to the first surface (102) and the third surface (104) is extending in a perpendicular manner from a first longitudinal side of the first surface (102). In an aspect, the second surface (103) and the third surface (104) are parallel to each other.
[0038] In an aspect, the joining arrangement of the surfaces (102, 103, 104, 105) are made to minimize deformation under loading conditions. Consequently, a uniform distribution of energy is achieved without any aggregation of localized stresses, thereby contributing to the robustness of the overall structure.
[0039] In an aspect, the first surface (102) of the extension quarter inner panel (100) includes two strengthening beads (106-1, 106-2) lying adjacent to each other and are parallel to each other. Herein, a first strengthening bead (106-1) is positioned adjacent to the second surface (104).
[0040] In an aspect, design of the two strengthening beads (106-1, 106-2) has been optimized for relieving the localized stress and also to change mode of the bending line of the cross sectional area. This is achieved by smoothening profile of the first strengthening bead (106-1) in lengthwise direction and by joining the first strengthening bead (106-1) with

the fourth surface (105) through a triangular surface (107). Consequently, the arrangement eliminates the localized stresses and maximizes flow of energy.
[0041] In an aspect, a fillet (108) is provided in the second surface (103) for smooth connection of second surface (103) with the third surface (104) and the fourth surface (105).
[0042] In an aspect, a fillet (109) is provided between first surface (102) and the third surface (104) to ensure a direct and continuous connection of the first surface (102) with the second surface (104). The fillet (109) is merged with the fillet (108) at a region just below the curved face and just before the start of the fourth surface (105) in an arrangement to maximise the flow of energy and thus contributing to rigidity of the structure.
[0043] In an aspect, the extension quarter inner panel (100) includes a first emboss (114-1) and a second emboss (114-2) on a fourth surface (105) that is formed above the first strengthening bead (106-1). A trim mounting bracket (not shown in FIG. 1) is spot welded to the embosses (114-1, 114-2). The triangular surface (107) is created between the second emboss (114-2) and the first strengthening bead (106-1) to relieve nearby area from localized stresses. Therefore, direct spot welding of the trim mounting bracket with the first strengthening bead (106-1) is prevented; as a result of which a cushioning effect is achieved at joinery site.
[0044] The structural features discussed here are also represented in FIG. 2 for better clarity and understanding. These are not reiterated here for the sake of brevity.
[0045] Referring to FIG. 3, the second surface (103) is having an elevated step profile (112) at curved region of the extension quarter inner panel (100) in order to increase stiffness of local region thus contributing to the rigidity of the overall structure.
[0046] FIG. 4 illustrates complete assembly of a D-pillar region of the vehicle formed by incorporating the extension quarter inner panel (100) as discussed in the previous section The fitment of the extension quarter inner panel (100) with the structural features discussed above alters the bending profile of the concerned region thereby enhancing stiffness of the overall structure.
[0047] Therefore, in this manner, the reinforced design provides additional stiffness to the extension quarter inner panel of the vehicle contributing to an enhanced robustness and rigidity to the structure as well.

Technical Advantages
[0048] All in all, the invention described in the present disclosure is having the following advantages:
a) Enhanced robustness
b) Enhanced rigidity
c) Reduced localized stresses due to optimized design of bead profile
d) Step profile of the flanges provides an additional stiffness to the entire structure
e) The proposed design features adopted are cost effective
Equivalents
[0049] It should be noted that the description and figures merely illustrate the principles of the present subject matter. It should be appreciated by those skilled in the art that conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present subject matter. It should also be appreciated by those skilled in the art that by devising various systems that, although not explicitly described or shown herein, embody the principles of the present subject matter and are included within its spirit and scope. Furthermore, all examples recited herein are principally intended expressly to be for pedagogical purposes to aid the reader in understanding the principles of the present subject matter and the concepts contributed by the inventor(s) to furthering the art and are to be construed as being without limitation to such specifically recited examples and conditions. The novel features which are believed to be characteristic of the present subject matter, both as to its organization and method of operation, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures.
[0050] Although embodiments for the present subject matter have been described in language specific to package features, it is to be understood that the present subject matter is not necessarily limited to the specific features described. Rather, the specific features and methods are disclosed as embodiments for the present subject matter. Numerous modifications and adaptations of the system/device of the present invention will be apparent

to those skilled in the art, and thus it is intended by the appended claims to cover all such modifications and adaptations which fall within the scope of the present subject matter.

We Claim:

1. An extension quarter inner panel (100) of a vehicle, comprising:
a first surface (102);
a second surface (103), wherein the second surface (103) is perpendicular to the first surface (102);
a third surface (104) extending perpendicularly from a first longitudinal side of the first surface (102); and
a fourth surface (105), wherein the first surface (102) is joined to the second surface (103) through the third surface (104) in straight region and through the fourth surface (105) in curved region of the extension quarter inner panel (100).
2. The extension quarter inner panel (100) as claimed in claim 1, wherein the extension quarter inner panel (100) includes a first strengthening bead (106-1) and a second strengthening bead (106-2) lying adjacent to each other and are parallel to each other.
3. The extension quarter inner panel (100) as claimed in claim 2, wherein the first strengthening bead (106-1) is positioned adjacent to the second surface (104).
4. The extension quarter inner panel (100) as claimed in claim 2, wherein the the first strengthening bead (106-1) is joined with the fourth surface (105) through a triangular surface (107).
5. The extension quarter inner panel (100) as claimed in claim 1, wherein a fillet (108) is provided in the second surface (103) and a fillet (109) is provided between the first surface (102) and the third surface (104), wherein the fillet (109) is merged with the fillet (108) at a region just below the curved face and just before the start of the fourth surface (105).
6. The extension quarter inner panel (100) as claimed in claim 1, wherein the second surface (103) includes an elevated step profile (112) at curved region of the extension quarter inner panel (100).
7. The extension quarter inner panel (100) as claimed in claim 4, further comprising a first emboss (114-1) and a second emboss (114-2) on a fourth surface (105).
8. The extension quarter inner panel (100) as claimed in claim 7, wherein the second emboss (114-2) is formed above the first strengthening bead (106-1).

9. The extension quarter inner panel (100) as claimed in claim 7, wherein the triangular surface (107) is created between the second emboss (114-2) and the first strengthening bead (106-1).