Description:FORM 2

THE PATENTS ACT, 1970
[39 OF 1970]
&
THE PATENTS RULES, 2003

COMPLETE SPECIFICATION
[SEE SECTION 10, RULE 13]

REAR WHEELHOUSE FOR A VEHICLE
BY
MAHINDRA ELECTRIC AUTOMOBILE LTD, INDIAN COMPANY, HAVING ADDRESS AT PLOT NO. 41/1, MAHINDRA WORLD CITY, ANJUR, CHENGALPATTU – 603004, TAMIL NADU, INDIA

THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED

TECHNICAL FIELD
[001] The present invention relates to a rear wheelhouse for a vehicle.

BACKGROUND
[002] Generally, it is known that a rear wheelhouse region height inherently is limited by governing parameters such as a tire size, a wheel articulation envelope and a vehicle packaging space. The rear wheelhouse region height significantly contributes towards a vehicle dynamic stiffness for suspension mountings in the rear wheelhouse region. The dynamic stiffness of the suspension mountings in-turn is directly proportional to noise, vibration, and harshness (NVH) of the vehicle.
[003] Figure 1 illustrates a conventional rear wheel arch zone of a vehicle (100) having a rear wheelhouse (105). Conventionally, a charger lid box or a fuel lid box (104) is mounted on a body side outer panel (110) of the vehicle (100). In such conventional vehicle (100), a height of the rear wheelhouse (105) is symmetrical on both sides of the vehicle (100). Therefore, to provide support for the charger lid box or the fuel lid box (104), a bracket (106) is provided. However, such provision of the bracket (106) acts as a tower overhang and has significant inherent limitations. The bracket (106) overhang creates a distorted structure feeling and fails to meet the stiffness criteria, appearance of the charger lid box or the fuel lid box (104) is modified with a zero flush condition leading to improper / mismatch locating of the charger lid box or the fuel lid box (104) with respect to the body side outer panel (110). Also, such a conventional arrangement further leads to decrease in dynamic stiffness of the suspension mountings (115) thereby leading to increase in noise, vibration, and harshness (NVH) of the vehicle.
[004] Therefore, conventionally it is also known that the rear wheelhouse (105) may extend vertically up to create a mounting surface for the charger lid box or the fuel lid box (104) thereby avoiding the use of the bracket (104). Figure 2 illustrates such a conventional rear wheel arch zone of a vehicle (100) having a rear wheelhouse (105). The fuel lid box or the charger lid box (104) mounted on a particular side (left or right) has different shape and height (H1 ? h1) compared to the other side where there is no charger lid box or fuel lid box. The different shape and vertical height extension of the rear wheelhouse from the long rail i.e. load path, which is almost 60% compared to the other side, attributes in housing and supporting the fuel lid box or the charger lid box (104).
[005] However, even with such vertical height extension of the wheelhouse (105) there still exist inherent limitation of decrease in dynamic stiffness of the suspension mountings (115) thereby leading to increase in noise, vibration, and harshness (NVH) of the vehicle. The vertical height extension of the wheelhouse (105) inherently reduces the panel stiffness due to asymmetricity of the rear wheelhouse (105). The issue of lower stiffness of wheelhouse effects vehicle body structure, when the rear wheelhouse (105) carries suspension mounting (115) through which road loads get input to the vehicle body structure. The heightened and bigger rear wheelhouse (105) is less stiff at the joinery of the vehicle body structure and has higher vibration response at the lid box side compared with the other side wheelhouse. The bigger rear wheelhouse has higher number of natural frequencies resulting in lower dynamic stiffness.
[006] Therefore, there exists a need to provide a rear wheelhouse that overcomes one or more of the aforementioned problems.

SUMMARY
[007] Accordingly, an exemplary aspect of the present invention discloses a rear wheelhouse for a vehicle. The rear wheelhouse comprises at least an asymmetrical region located at a left-hand side or a right-hand side of said vehicle. The asymmetrical region is defined by a height within said rear wheelhouse. The rear wheelhouse further includes a rear wheelhouse outer surface and a rear wheelhouse inner surface, both defined by a rear wheel articulation envelope. The rear wheelhouse’s outer surface extends outwardly within the defined height of the asymmetrical region. The rear wheelhouse’s inner surface extends inwardly within the defined height of the asymmetrical region. The rear wheelhouse also includes a towering bracket located within the rear wheelhouse, that extends along the rear wheelhouse’s inner surface within the defined height of the asymmetrical region. A plurality of suspension mountings are mounted on said towering bracket for receiving a road load. The rear wheelhouse furthermore includes a reinforcement structure having at least an outwardly projecting flange. The reinforcement structure is coupled within the rear wheelhouse. The reinforcement structure is defined within the defined height of the asymmetrical region abutting and extending along said rear wheelhouse outer surface and said rear wheelhouse inner surface. The reinforcement structure supports the rear wheelhouse, the towering bracket and a charger lid box or a fuel lid box mounted on a body side outer panel of the vehicle with a zero flush mounting surface, thereby increasing a vehicle dynamic stiffness with constrained noise, vibration, and harshness (NVH) of the vehicle.

BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS
[008] The above and other aspects, features, and advantages of certain exemplary embodiments of the present invention will be more apparent from the following description taken in conjunction with the accompanying drawings in which:
[009] Figure 1 illustrates a conventional rear wheel arch zone front view of a vehicle having a rear wheelhouse;
[010] Figure 2 illustrates another conventional rear wheel arch zone front view of a vehicle having a rear wheelhouse;
[011] Figure 3 illustrates a side and a bottom view of a rear wheelhouse with a reinforcement structure, according to an exemplary aspect of the present invention;
[012] Figure 4 illustrates a rear wheel arch zone front view of a vehicle having a rear wheelhouse with the reinforcement structure, according to an exemplary embodiment of the present invention; and
[013] Figure 5 illustrates a detailed bottom view of a rear wheelhouse with the reinforcement structure, according to the exemplary embodiment of the present invention.
[014] Persons skilled in the art will appreciate that elements in the figures are illustrated for simplicity and clarity and may have not been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to the other elements to help improve understanding of various exemplary embodiments of the present disclosure. Throughout the drawings, it should be noted that like reference signs are used to depict the same or similar elements, features, and structures.

DETAILED DESCRIPTION
[015] While this invention is susceptible of embodiments in many different forms, there is shown in the drawings and will herein be described in detail, a preferred embodiment of the invention with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the broad aspects of the invention to the embodiment illustrated.
[016] Other aspects, advantages, and salient features of the invention will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses exemplary embodiments of the invention. Embodiments of the present disclosure will now be described with reference to the accompanying drawings. Embodiments are provided so as to thoroughly and fully convey the scope of the present disclosure to a person skilled in the art. Numerous details are set forth relating to specific components to provide a complete understanding of embodiments of the present disclosure. It will be apparent to the person skilled in the art that the details provided in the embodiments should not be construed to limit the scope of the present disclosure. In some embodiments, well-known processes, well-known apparatus structures, and well-known techniques are not described in detail.
[017] In general, the present invention discloses a rear wheelhouse for a vehicle having a reinforcement structure for supporting the rear wheelhouse, a towering bracket and a charger lid box or a fuel lid box mounted on a body side outer panel of the vehicle with a zero flush mounting surface, thereby increasing a vehicle dynamic stiffness with constrained noise, vibration, and harshness (NVH) of vehicle.
[018] According to an exemplary aspect, the present invention discloses a rear wheelhouse for a vehicle. The rear wheelhouse comprises at least an asymmetrical region located at a left-hand side or a right-hand side of said vehicle. The asymmetrical region is defined by a height within said rear wheelhouse. The rear wheelhouse further includes a rear wheelhouse outer surface and a rear wheelhouse inner surface, both defined by a rear wheel articulation envelope. The rear wheelhouse’s outer surface extends outwardly within the defined height of the asymmetrical region. The rear wheelhouse’s inner surface extends inwardly within the defined height of the asymmetrical region. The rear wheelhouse also includes a towering bracket located within the rear wheelhouse, that extends along the rear wheelhouse’s inner surface within the defined height of the asymmetrical region. A plurality of suspension mountings are mounted on said towering bracket for receiving a road load. The rear wheelhouse furthermore includes a reinforcement structure having at least an outwardly projecting flange. The reinforcement structure is coupled within the rear wheelhouse. The reinforcement structure is defined within the defined height of the asymmetrical region abutting and extending along said rear wheelhouse outer surface and said rear wheelhouse inner surface. The reinforcement structure supports the rear wheelhouse, the towering bracket and a charger lid box or a fuel lid box mounted on a body side outer panel of the vehicle with a zero flush mounting surface, thereby increasing a vehicle dynamic stiffness with constrained noise, vibration, and harshness (NVH) of the vehicle.
[019] According to an exemplary embodiment, the reinforcement structure is a single structure unit coupled within said rear wheelhouse by spot welding or bolting or a combination thereof. The reinforcement structure compensates for said asymmetrical region (R) defined by said height (H1) within said rear wheelhouse increasing the dynamic stiffness in the range of at least 15-20%.
[020] According to the exemplary embodiment, the reinforcement structure includes a cut-out for passing a routing cable.
[021] According to another exemplary embodiment, the reinforcement structure is split into at least two or more structure units. A first split structure unit is welded or bolted to an under-vehicle body assembly and a second split structure unit is welded or bolted to the body side outer assembly.
[022] According to the exemplary embodiment, a parting line is formed at an area of joining of the first and second split structure, each split structure having said outwardly projecting flange abutting against each other. The parting line is spot welded to form a single integrated joint reinforcement structure.
[023] The terminology used, in the present disclosure, is only for the purpose of explaining a particular embodiment and such terminology shall not be considered to limit the scope of the present disclosure. The use of the expression “at least” or “at least one” suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the disclosure to achieve one or more of the desired objects or results. As used in the present disclosure, the forms “a,” “an,” and “the” may be intended to include the plural forms as well, unless the context clearly suggests otherwise. The terms “comprises,” “comprising,” “including,” “made of” and “having,” are open ended transitional phrases.
[024] The terms and words used in the following description and claims are not limited to the bibliographical meanings, but are merely used by the inventor to enable a clear and consistent understanding of the invention. Accordingly, it should be apparent to those skilled in the art that the following description of exemplary embodiments of the present invention for example of rear wheelhouse referred in the description are provided are for illustration purpose and understanding only and not for the purpose of limiting the invention as defined by the appended claims and their equivalents. The skilled person will be able to devise various structures, shapes and components of the rear wheelhouse, although not explicitly described herein, embody the principles of the present invention. All the terms and expressions in the description are only for the purpose of the understanding and nowhere limit the invention. Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein may be made without departing from the scope of the invention. Terms like left and right, first, second, top, bottom, extending inwards, extending outwards, forward, rearward, left-hand side, right hand side and the like are used to differentiate between objects having the same terminology and are in no way intended to represent a chronological order, unless where explicitly stated otherwise. Moreover, all statements herein reciting principles, aspects, and embodiments of the invention, as well as specific examples thereof, are intended to encompass equivalents thereof. Thus, while particular type of structure, material, thickness, area, height, width, length, shape, diameters, quantity, numbers, mass, frequencies, mounting brackets, suspension mountings, dynamic stiffness values, projecting flanges have been disclosed, such components and parameters nowhere limit the invention and are provided for understanding of the invention. It will be appreciated that the embodiments may be manufactured with other design parameters and configurations as well and are not limited to those described herein above may be as per operational requirements by making necessary changes and is not limited to those described herein and nowhere limits the scope of the invention and are provided only for reference and for understating purpose of the invention.
[025] Figures 3-5 disclose a vehicle (200), a rear wheelhouse (205), an asymmetrical region (R), a height (H1), a body side outer panel (210), a rear wheelhouse outer surface (220); a rear wheelhouse inner surface (225), at least a towering bracket (228); a plurality of suspension mountings (215), cut-out (230), an outwardly projecting flange (240), a parting line (250), a reinforcement structure (300), a first split structure unit (310), a second split structure unit (320).
[026] Figures 3-5, according to an exemplary embodiment, disclose a reinforcement structure (300) that increases stiffness of the rear wheelhouse (205). The structure (300) is adapted to the rear wheelhouse (205) monocoque body in white (BIW) for any vehicle that includes but not limited to an electric vehicle (EV), an internal combustion engine (ICE) vehicle.
[027] As seen in the Figure 3, a vehicle body has fuel/charge port/ lid mounting on left hand side and therefore, the rear wheelhouse height is more compared to right hand side. As seen in the Figure 4, the vertical height extension of the rear wheelhouse (205) on the left-hand side is more than the right-hand side (H1?h1). Due to this, the rear wheelhouse (205) on the left-hand side, if subjected to load, has less stiffness as compared to the right-hand side due to a cantilever effect. However, the reinforcement structure (300) mounted within the rear wheelhouse (205) aids to increase the dynamic stiffness thereby reducing noise, vibration, and harshness (NVH) of the vehicle. The rear wheelhouse inner (225) and outer (220) lateral breathing modes / natural frequencies are constrained with the reinforcement structure, whereby response of the wheelhouse and surrounding panels with respect to the road load through rear shock tower is reduced. With less propagation of vibration from road to rest of the body structure, the reinforcement structure (300) reduces structure borne noise inside the cabin. The reinforcement structure (300) at the left-hand side forms strong mounting for rear shock tower similar to right-hand side.
[028] According to the present invention, the reinforcement structure (300) solves the problem of lower dynamic stiffness of rear wheelhouse (205) inherent due to its height. The reinforcement structure (300) improves vehicle dynamics and cabin noise performance. The reinforcement structure (300) forms a structural link between rear wheelhouse inner (225) and rear wheelhouse outer (220), avoids lateral movement or match-boxing effect. The reinforcement structure (300) addresses the structural and NVH issue with significantly lower weight and cost as compared to increasing the thickness of the wheelhouse part and reinforcement members. The rear wheelhouse (205) with reinforcement structure (300) gives weight and cost advantage at required performance. The reinforcement structure (300) may be applied to vehicles wherein fuel port or charge port is mounted on rear wheelhouse (205) and the body design becomes non-symmetric or any other geometric constraints which leads to increased height of wheelhouse.
[029] Example: The following table shows the dynamic stiffness values for a vehicle having a base design and a vehicle having reinforcement structure (300) adapted to the rear wheelhouse (205). The table shows increased dynamic stiffness values with reinforcement structure (300).
Base design With reinforced structure (300)
Dynamic stiffness, kgf/mm 1297 1601
[030] According to the exemplary embodiment, the reinforcement structure (300) may be either steel, or plastic or any alternate material with proper stiffening elements like beads, ribs, webs etc. To compensate for the increased height of the rear wheelhouse, reinforcement structure (300) is used. The reinforcement structure (300) may be a single unit or a split unit for ease of manufacturing and assembly. The reinforcement structure (300) may be spot welded, bolted or joined with rest of the body of the vehicle with appropriate assembly method depending on the material compatibility.
[031] According to the exemplary embodiment, a cut-out (230) is provided within the reinforcement structure (300) for passing routing cables and other routings. The reinforcement structure (300) attaches from wheelhouse outer (220) to wheelhouse inner (225). The reinforcement structure (300) includes at least an outwardly projecting flange (240).
[032] According to the exemplary embodiment, the reinforcement structure (300) may be split into two or more units. A first split structure unit (310) is welded or bolted or coupled using known techniques to an under-vehicle body assembly and a second split structure unit (320) is welded or bolted or coupled using known techniques to the body side outer assembly (210). A parting line (250) is formed at an area of joining of the first and second split structure (310, 320) for spot welding. Each outwardly projecting flange (240) of the first and second split structure (310, 320) are abutting against each other, and spot welding is performed to form a single integrated joint reinforcement structure (300).
[033] According to an exemplary aspect, the present invention discloses a rear wheelhouse (205) for a vehicle (200). The rear wheelhouse (205) comprises at least an asymmetrical region (R) located at a left-hand side or a right-hand side of said vehicle (200). The asymmetrical region is defined by a height (H1) within said rear wheelhouse (205). The rear wheelhouse (205) further includes a rear wheelhouse outer surface (220) and a rear wheelhouse inner surface (225), both defined by a rear wheel articulation envelope. The rear wheelhouse’s outer surface (220) extends outwardly within the defined height (H1) of the asymmetrical region (R). The rear wheelhouse’s inner surface (225) extends inwardly within the defined height (H1) of the asymmetrical region (R). The rear wheelhouse (205) also includes a towering bracket (228) located within the rear wheelhouse (205), that extends along the rear wheelhouse’s inner surface (225) within the defined height (H1) of the asymmetrical region (R). A plurality of suspension mountings (215) are mounted on said towering bracket (228) for receiving a road load. The rear wheelhouse (205) furthermore includes a reinforcement structure (300) having at least an outwardly projecting flange (240). The reinforcement structure (300) is coupled within the rear wheelhouse (205). The reinforcement structure (300) is defined within the defined height (H1) of the asymmetrical region (R) abutting and extending along said rear wheelhouse outer surface (220) and said rear wheelhouse inner surface (225). The reinforcement structure (300) supports the rear wheelhouse (205), the towering bracket (228) and a charger lid box or a fuel lid box mounted on a body side outer panel (210) of the vehicle (200) with a zero flush mounting surface, thereby increasing a vehicle dynamic stiffness with constrained noise, vibration, and harshness (NVH) of the vehicle (200).
[034] There have been described and illustrated herein several embodiments of exemplary indicative implementation of a rear wheelhouse (205) having the reinforcement structure (300). It will also be apparent to a skilled person that the embodiments described above are specific examples of a single broader invention, which may have greater scope than any of the singular descriptions taught. There may be many alterations made in the description without departing from the scope of the invention. The present invention is simple in construction and design, integrated, cost effective and easy to manufacture and assemble and integrated with existing vehicles also. While particular embodiments of the invention have been described, it is not intended that the invention be limited to said configuration disclosed thereto, as it is intended that the invention be as broad in scope as the art will allow and that the specification be read likewise not restrictive to the terminology described herein above. Any discussion of embodiments included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all of these matters form a part of the prior art base or were common general knowledge in the field relevant to the disclosure as it existed anywhere before the priority date of this application.

, Claims:We claim:
1. A rear wheelhouse (205) for a vehicle (200), said rear wheelhouse (205) comprising:
at least an asymmetrical region (R) located at a left-hand side or a right-hand side of said vehicle (200), said asymmetrical region (R) defined by a height (H1) within said rear wheelhouse (205);
a rear wheelhouse outer surface (220) defined by a rear wheel articulation envelope, said rear wheelhouse outer surface (220) extending outwardly within said height (H1);
a rear wheelhouse inner surface (225) defined by said rear wheel articulation envelope, said rear wheelhouse inner surface (225) extending inwardly within said height (H1);
at least a towering bracket (228) located within said rear wheelhouse (205), said towering bracket (228) extending along said rear wheelhouse inner surface (225) within said height (H1);
a plurality of suspension mountings (215) mounted on said towering bracket (228) for receiving a road load; and
a reinforcement structure (300) having an outwardly projecting flange (240), coupled within said rear wheelhouse (205), said reinforcement structure (300) defined within said height (H1) abutting and extending along said rear wheelhouse outer surface (220) and said rear wheelhouse inner surface (225) supports said rear wheelhouse (205), said towering bracket (228) and a charger lid box or a fuel lid box mounted on a body side outer panel (210) of said vehicle (200) with a zero flush mounting surface, thereby increasing a vehicle dynamic stiffness with constrained noise, vibration, and harshness (NVH) of said vehicle (200).

2. The rear wheelhouse (205) as claimed in claim 1, wherein the reinforcement structure (300) is a single structure unit.

3. The rear wheelhouse (205) as claimed in claim 1 or 2, wherein the reinforcement structure (300) is coupled within said rear wheelhouse (205) by spot welding or bolting or a combination thereof.

4. The rear wheelhouse (205) as claimed in anyone of the preceding claims 1-3, wherein the reinforcement structure (300) compensates for said asymmetrical region (R) defined by said height (H1) within said rear wheelhouse (205) increasing the dynamic stiffness in the range of at least 15-20%.

5. The rear wheelhouse (205) as claimed in anyone of the preceding claims 1-4, the reinforcement structure (300) includes a cut-out (230) for passing a routing cable.

6. The rear wheelhouse (205) as claimed in anyone of the preceding claims 1-5, wherein the reinforcement structure (300) is split into at least two or more structure unit.

7. The rear wheelhouse (205) as claimed in claim 6, wherein a first split structure unit (310) is welded or bolted to an under-vehicle body assembly and a second split structure unit (320) is welded or bolted to the body side outer assembly (210).

8. The rear wheelhouse (205) as claimed in anyone of the preceding claims 6-7, wherein a parting line (250) is formed at an area of joining of the first and second split structure (310, 320), each split structure (310, 320) having said outwardly projecting flange (240) abutting against each other.

9. The rear wheelhouse (205) as claimed in anyone of the preceding claims 6-8, wherein said parting line (250) is spot welded to form a single integrated joint reinforcement structure (300).

Dated this 29th day of March, 2024

For MAHINDRA ELECTRIC AUTOMOBILE LTD
By their Agent

(GIRISH VIJAYANAND SHETH) (IN/PA 1022)
KRISHNA & SAURASTRI ASSOCIATES LLP