The present disclosure relates generally to a vehicle rear body structure and in particular relates to a vehicle rear body structure for stress distribution in rear door closing region.
BACKGROUND
[0002] In vehicles, a tailgate is provided to open and close an entrance portion for a rear seat or cargo compartment. Periphery of the entrance portion serves as a tailgate reception portion for receiving periphery of the tailgate. This periphery of the entrance portion is a closed structure comprising a side body outer extension panel, a quarter inner panel, a rear lamp house outer panel and a rear lamp house inner panel. This closed structure is maintained on both the right and left side of the tailgate.
[0003] The quarter inner panel is provided on the inner side of the side body extension outer panel. The rear lamp house outer panel is securely attached to the lower portion of the side body extension outer panel. The rear lamp house inner panel is securely attached to the rear lamp house outer panel and lower portion of the quarter inner panel. Together, the side body outer extension panel, the quarter inner panel, the rear lamp house outer panel and the rear lamp house inner panel form a rigid structure.
[0004] Suspensions are provided in the vehicle to ensure safe and smooth ride, as the suspension absorbs energy from various road bumps and other kinetic impacts. When loads act on the suspension, the loads are channelized through the attachment points to the vehicle body towards the closed structure formed by the side body outer extension panel, the quarter inner panel, the rear lamp house outer panel and the rear lamp house inner panel. As a result, the closed structure is likely

to experience the loads traveling along the channelized path on both the right and left sides of the rear door.
[0005] Among the panels of the close structure, rear lamp house inner panel is prone to experience the loads due to its design. As a result, it is likely that the rear lamp house inner panel is deformed in the vehicle front back direction on both the left and right sides by experiencing twisting motion of the vehicle body due to the channelized path of load from the attachment points.
[0006] Generally, the problem of deformation in the closed structure formed by the side body outer extension panel, the quarter inner panel, the rear lamp house outer panel and the rear lamp house inner panel is solved by providing a reinforcement in the deformation prone regions. However, the reinforcement provided in the deformation prone regions has limited ability to enhance the rigidity.
[0007] Accordingly, there is a need for a vehicle rear body structure for uniform stress distribution in rear door closing region to enhance rigidity of the closed structure and reduce deformation in rear lamp house inner panel on application of loads from the attachment points to the vehicle body.
SUMMARY
[0008] This summary is provided to introduce concepts related to a vehicle rear body structure for load distribution in rear door closing region. 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.
[0009] The present subject matter relates to a vehicle rear body structure for load distribution in rear door closing region. The vehicle rear body structure comprises a side body extension outer panel, a quarter inner panel, a rear lamp house outer panel and the rear lamp house inner panel. The quarter inner panel is provided on the inner side of the side body extension outer panel. The rear lamp

house outer panel is securely attached to the lower portion of the side body extension outer panel. The rear lamp house inner panel has an upper portion, a lower portion and a middle portion. The upper portion has its top end securely attached with the lower end of the quarter inner panel. The lower portion has its lower end securely attached to a tail end member creating a first junction point. The middle portion has a bend region in between the upper portion and the lower portion. The rear lamp house inner panel is securely attached to the rear lamp house outer panel in the bend region creating a second junction point.
[0010] The rear lamp house inner panel has a first edge with wedge shaped profile in the middle portion. The rear lamp house inner panel has a fillet provided longitudinally along the first edge, in the upper portion.
[0011] In an aspect, the rear lamp house inner panel, in the middle portion, has a hole provided in the vicinity of the wedge shaped profile, creating a depression around the hole in the bend region.
[0012] In an aspect, the rear lamp house inner panel is securely attached to the rear lamp house outer panel at the second junction point using spot welding.
[0013] In an aspect, a raised profile with bead is embossed on the edge of the depression in middle of the bend region creating an elevation.
[0014] In an aspect, width of the fillet decreases gradually from base to top creating a beak shaped profile.
[0015] In an aspect, the top of the fillet merges with the upper portion of the rear lamp house inner panel.
[0016] In an aspect, the lower end of the rear lamp house inner panel is securely attached to the tail end member at the first junction point using spot welding.
[0017] In an aspect, a step profile is provided at the lower end of the rear lamp house inner panel.

[0018] In an aspect, width of the middle portion of the rear lamp house inner panel is more as compared to that of the upper portion and the lower portion for uniform distribution of load in the bend region.
[0019] 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.
[0020] 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 like numerals represent like components.
BRIEF DESCRIPTION OF FIGURES
[0021] The illustrated embodiments of the present disclosure will be best understood by reference to the drawings, wherein like parts are designated by like numerals throughout. The following description is intended only by way of example, and simply illustrates certain selected embodiments of the vehicle side body structure that are consistent with the subject matter as claimed herein, wherein:
[0022] FIG. 1 illustrates an assembled view of exemplary vehicle rear body structure that can be utilized to implement one or more exemplary embodiments of the present disclosure;
[0023] FIG. 2 illustrates an exploded view of exemplary vehicle rear body structure that can be utilized to implement one or more exemplary embodiments of the present disclosure;
[0024] FIG. 3 illustrates front view of the exemplary rear lamp house inner panel that can be utilized to implement one or more exemplary embodiments of the present disclosure;

[0025] FIG. 4 illustrates a zoomed view of middle portion of the exemplary rear lamp house inner panel that can be utilized to implement one or more exemplary embodiments of the present disclosure;
[0026] FIG. 5 illustrates a zoomed view of upper portion of the exemplary rear lamp house inner panel that can be utilized to implement one or more exemplary embodiments of the present disclosure; and
[0027] FIG. 6 illustrates a zoomed view of lower portion of the exemplary rear lamp house inner panel that can be utilized to implement one or more exemplary embodiments of the present disclosure.
[0028] 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
[0029] A few aspects of the present disclosure are explained in detail below with reference to the various figures. Example implementations are described to illustrate the disclosed subject matter, not to limit its scope, which is defined by the claims. Those of ordinary skill in the art will recognize a number of equivalent variations of the various features provided in the description that follows.
Definitions
[0030] In the disclosure hereinafter, one or more terms are used to describe various aspects of the present disclosure. For a better understanding of the present disclosure, a few definitions are provided herein for better understanding of the present disclosure.
[0031] "First Junction Point' may be defined as point of attachment between the rear house inner panel and the tail end member.

[0032] "Second Junction Point' may be defined, in the context of the disclosure, as the point of attachment between the rear lamp house inner panel and the rear lamp house outer panel.
[0033] "Load channel path" may be defined, in the context of the disclosure, as region where load travels from the attachment point is more than the other regions.
[0034] "Closed Structure'" may be defined as a structure formed by side body outer panel, quarter inner panel, rear lamp house outer panel and rear lamp house inner panel resulting in a closed body configuration.
EXEMPLARY EMBODIMENTS
[0035] While the present disclosure may be embodied in various forms, there are shown in the drawings, and will hereinafter be described, some exemplary and non-limiting embodiments, with the understanding that the present disclosure is to be considered an exemplification of the invention and is not intended to limit the invention to the specific embodiments illustrated. Not all of the depicted components described in this disclosure may be required, however, and some implementations may include additional, different, or fewer components from those expressly described in this disclosure. Variations in the arrangement and type of the components may be made without departing from the scope of the claims as set forth herein.
[0036] The structure of the vehicle body in the rear door opening region is designed to withstand load received in the rear door opening region from the attachment points in the structure. However, the rigidity of the vehicle rear body structure is not same all over the structure and some regions are prone to experience bending on application of load. Rear lamp house inner panel is one such panel, which due to its design, which may experience the deflection on transfer of load along this path.
[0037] To solve the problem, a vehicle rear body structure capable of better stress distribution in rear door closing region is needed.

[0038] In order to achieve this goal of better stress distribution in rear door closing region, a vehicle rear body structure for uniform stress distribution may be utilized. The features of the vehicle rear body structure are described in more detail below.
[0039] FIG. 1 illustrates an assembled view of exemplary vehicle rear body structure that can be utilized to implement one or more exemplary embodiments of the present disclosure. The vehicle rear body structure 100 comprises a side body extension outer panel (shown in FIG. 2), a quarter inner panel 101, a rear lamp house outer panel 102 and a rear lamp house inner panel 103. The vehicle rear body structure 100 is implemented on the left and right periphery of the vehicle rear door. Due to repetitive application of loads from the suspension in this region, the vehicle rear body structure 100 is constructed as a highly rigid structure. The vehicle rear body structure 100 is given a closed body configuration to maintain rigidity.
[0040] FIG. 2 illustrates an exploded view of exemplary vehicle rear body structure that can be utilized to implement one or more exemplary embodiments of the present disclosure. The closed body configuration is provided to the vehicle rear body structure 100 by interconnecting the side body extension outer panel 201, the quarter inner panel 101, the rear lamp house outer panel 102 and the rear lamp house inner panel 103. The diagram clearly illustrates joining points among the side body extension outer panel 201, the quarter inner panel 101, the rear lamp house outer panel 102 and the rear lamp house inner panel 103.
[0041] The quarter inner panel 101 is provided on inner side of the side body extension outer panel 201. The rear lamp house outer panel 102 is securely attached to the lower portion of the side body extension outer panel 201. The rear lamp house inner panel 103 is securely attached to the rear lamp house outer panel 102 and lower portion of the quarter inner panel 101. Further, lower end of the rear lamp house inner panel 103 is securely attached to the tail end member 202. Together, the quarter inner panel 101, the side body extension outer panel 201, the rear lamp house outer panel 102 and the rear lamp house inner panel 103 creates a closed body configuration. This result in highly rigid structure. In an aspect, the panels 101, 201,

102, 103, and 202 are securely attached to each other using spot welding. As discussed above, rear lamp house inner panel 103 is one such panel, which due to its bendy design, is prone to deformation on application of loads by the rear suspensions. To enhance the rigidity of the vehicle rear body structure 100, some provisions are provided in the rear lamp house inner panel 103.
[0042] FIG. 3 illustrates front view of the exemplary rear lamp house inner panel 103 that can be utilized to implement one or more exemplary embodiments of the present disclosure. The rear lamp house inner panel 103 has an upper portion 301, a middle portion 302 and a lower portion 303. The upper portion 301 of the rear house inner panel 103 has a top end 304 which is securely attached to lower end of the quarter inner panel 101. In an aspect, the top end 304 of the rear house inner panel 103 is attached to lower end of the quarter inner panel 101 using spot welding.
[0043] The lower portion 303 of the rear house inner panel 103 has a lower end 305 which is securely attached to a tail end member 202. The point of attachment between the rear house inner panel 103 and the tail end member 202 creates a first junction point 306. In an aspect, the rear house inner panel 103 is attached to the tail end member 202 using spot welding.
[0044] The middle portion 302 of the rear lamp house inner panel 103 has a bend region 307. This bend region 307 is located between the upper portion 301 and the lower portion 303. The rear lamp house inner panel 103 is securely attached to the rear lamp house outer panel 102 in the bend region 307. The point of attachment between the rear lamp house inner panel 103 and the rear lamp house outer panel 102 creates a second junction point 308. In an aspect, the rear lamp house inner panel 103 is securely attached to the rear lamp house outer panel 102 using spot welding. Due to presence of bend region 307 in the middle portion 302 of the rear lamp house inner panel 103, the middle portion 302 is vulnerable to deformation on application of loads by the attachment points in the vehicle body. This results in creation of high load concentration in bend region 307. Some

provisions are provided in the middle portion 302 of the rear lamp house inner panel 103 to eliminate the vulnerability of the bend region 307 towards deformation.
[0045] FIG. 4 illustrates a zoomed view of middle portion of the exemplary rear lamp house inner panel that can be utilized to implement one or more exemplary embodiments of the present disclosure. One particular region which is vulnerable to deformation in the middle portion 302 of the rear lamp house inner panel 103 is first edge region 401. The rigidity of the first edge region 401 is compromised as the region servers as a second junction point 308 created by securely attaching the rear lamp house inner panel 103 with the rear lamp house outer panel 102. To enhance rigidity of first edge region 401 of the middle portion 302, a wedge shaped profile 403 is provided to increase stiffness of the second junction region 308. The wedge shaped profile 403 facilitates joining of the rear lamp house inner panel 103 with the rear lamp house outer panel 102. In an aspect, the rear lamp house inner panel 103 is spot welded with the rear lamp house outer panel 102 through this wedge shaped profile 403 enhancing the rigidity of the first edge 401 region at the second junction point 308.
[0046] In addition, a hole 404 is provided in the vicinity of the wedge shaped profile 403 for wire harness going towards the lamp housing. Further, a depression 405 is formed around the hole 404 in the bend region 307 in the periphery of the first edge 401. Further, a raised profile 406 with bead is embossed on the edge of the depression 405 in the middle of the bend region 307. The raised profile 406 with bead creates an elevation 407 in the periphery of the second edge 402 to improve rigidity in the bend region 307 near the second edge 402 of the middle portion 302 of the rear lamp housing inner panel 103. Thus, the middle portion 302 of the rear lamp housing inner panel 103 has a depression 405 and an elevation 407 resulting in better load distribution. Furthermore, width of the middle portion 302 of the rear lamp house inner panel 103 is more as compared to that of the upper portion (301) and the lower portion (303) for better load distribution in the bend region 307.

[0047] In addition to the above provisions, a flat contour 408 is maintained around the edges of the wedge shaped profile 403 to enhance uniform load distribution in the vicinity of the wedge shaped profile 403.
[0048] FIG. 5 illustrates a zoomed view of upper portion of the exemplary rear lamp house inner panel that can be utilized to implement one or more exemplary embodiments of the present disclosure. The first edge region 401 in the vicinity of the wedge shaped profile 403 is also a high load region due to presence of second junction point 308 in the vicinity. To enhance the rigidity of this region, a fillet 501 is provided longitudinally along the first edge region 401 to enhance the rigidity of the first edge region 401. Further, the width of the fillet 501 decreases gradually creating a beak shaped profile (shown in the figure with dotted line). The width of the fillet 501 is decreasing in a manner that the width is maximum in the base 501a in the vicinity of the wedge shaped profile 403 and the width is minimum in the top 501b in the vicinity of the top end 304 of the upper portion 301. Contour of the top 501b of the fillet 501 is identical to the contour of the nearby region in the upper portion 301 of the rear lamp house inner panel 103. Thus, the top 501b of the fillet 501 merges with the upper portion 301 of the rear lamp house inner panel 103 resulting in elimination of any possibility of formation of load concentration zone in the vicinity of the top 501b of the fillet 501. In an aspect, the fillet 501 is provided on both upper and lower sides of the wedge shaped profile 403.
[0049] FIG. 6 illustrate a zoomed view of lower portion of the exemplary rear lamp house inner panel that can be utilized to implement one or more exemplary embodiments of the present disclosure. The lower portion 303 of the rear lamp housing inner panel 103 is securely attached to the tail end member 202 forming the first junction point 306. To increase rigidity at the first junction point 306, a step profile 601 is provided at the first junction point 306. The step profile 601 protects the first junction point 306 from high load concentration.
ADVANTAGES
[0050] The proposed vehicle rear body structure is capable of uniform distribution of load in rear door closing region to enhance rigidity of the close

structure and eleminate deformation in rear lamp house inner panel on application of load from theattachment points in the structure. Further, the vehicle rear body structure eliminates possibility of formation of high load concentration zones in the rear lamp house inner panel.
[0051] The above description does not provide specific details of the manufacture or design of the various components. Those of skill in the art are familiar with such details, and unless departures from those techniques are set out, techniques, known, related art or later developed designs and materials should be employed. Those in the art are capable of choosing suitable manufacturing and design details.
[0052] Further, the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. It will be appreciated that several of the above-disclosed and other features and functions, or alternatives thereof, may be combined into other systems or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations, or improvements therein may subsequently be made by those skilled in the art without departing from the scope of the present disclosure as encompassed by the following claims.
[0053] The claims, as originally presented and as they may be amended, encompass variations, alternatives, modifications, improvements, equivalents, and substantial equivalents of the embodiments and teachings disclosed herein, including those that are presently unforeseen or unappreciated, and that, for example, may arise from applicants/patentees and others.
[0054] It will be appreciated that variants of the above-disclosed and other features and functions, or alternatives thereof, may be combined into many other different systems or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations, or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the following claims.

A vehicle rear body structure (100) comprising:
a side body extension outer panel (201);
a quarter inner panel (101) provided on inner side of the side body extension outer panel (201);
a rear lamp house outer panel (102) securely attached to the lower portion of the side body extension outer panel (201); and
a rear lamp house inner panel (103) having an upper portion (301) with top end (304) securely attached with lower end of the quarter inner panel (101), a lower portion (303) with lower end (305) securely attached to a tail end member (202) creating a first junction point (306) and a middle portion (302) with a bend region (307) in between the upper portion (301) and the lower portion (303), wherein the rear lamp house inner panel (103) is securely attached to the rear lamp house outer panel (102) in the bend region (307) creating a second junction point (308),
characterized in that
the rear lamp house inner panel (103), in the middle portion (302), has a first edge (401) with a wedged shaped profile (403); and
the rear lamp house inner panel (103), in the upper portion (301), has a fillet (501) provided longitudinally along the first edge (401).
The vehicle rear body structure (100) as claimed in claim 1, wherein the rear lamp house inner panel (103), in the middle portion (302), has a hole (404) provided in the vicinity of the wedge shaped profile (403), creating a depression (405) around the hole (404) in the bend region (307).

WE CLAIM

1. A vehicle rear body structure (100) comprising:
a side body extension outer panel (201);
a quarter inner panel (101) provided on inner side of the side body extension outer panel (201);
a rear lamp house outer panel (102) securely attached to the lower portion of the side body extension outer panel (201); and
a rear lamp house inner panel (103) having an upper portion (301) with top end (304) securely attached with lower end of the quarter inner panel (101), a lower portion (303) with lower end (305) securely attached to a tail end member (202) creating a first junction point (306) and a middle portion (302) with a bend region (307) in between the upper portion (301) and the lower portion (303), wherein the rear lamp house inner panel (103) is securely attached to the rear lamp house outer panel (102) in the bend region (307) creating a second junction point (308),
2. characterized in that
the rear lamp house inner panel (103), in the middle portion (302), has a first edge (401) with a wedged shaped profile (403); and
the rear lamp house inner panel (103), in the upper portion (301), has a fillet (501) provided longitudinally along the first edge (401).
The vehicle rear body structure (100) as claimed in claim 1, wherein the rear lamp house inner panel (103), in the middle portion (302), has a hole (404) provided in the vicinity of the wedge shaped profile (403), creating a depression (405) around the hole (404) in the bend region (307).

3. The vehicle rear body structure (100) as claimed in claim 1, wherein the rear lamp house inner panel (103) is securely attached to the rear lamp house outer panel (102) at the second junction point (308) using spot welding.
4. The vehicle rear body structure (100) as claimed in claim 2, wherein a raised profile (406) with bead is embossed on the edge of the depression (405) in middle of the bend region (307) creating an elevation (407).
5. The vehicle rear body structure (100) as claimed in claim 1, wherein width of the fillet (501) decreases gradually from base (501a) to top (501b) creating a beak shaped profile.
6. The vehicle rear body structure (100) as claimed in claim 5, wherein the top (501b) of the fillet (501) merges with the upper portion (301) of the rear lamp house inner panel (103).
7. The vehicle rear body structure (100) as claimed in claim 1, wherein the lower end (305) of the rear lamp house inner panel (103) is securely attached to the tail end member (202) at the first junction point (306) using spot welding.
8. The vehicle rear body structure (100) as claimed in claim 1, wherein a step profile (601) is provided at the lower end (305) of the rear lamp house inner panel (103).

9. The vehicle rear body structure (100) as claimed in claim 1, wherein width of the middle portion (302) of the rear lamp house inner panel (103) is more as compared to that of the upper portion (301) and the lower portion (303) for uniform distribution of load in the bend region (307).