Description:A DOUBLE HEADED FASTENING STUD FOR FENDER BODY OF AN AUTOMOBILE

FIELD OF THE DISCLOSURE
[0001] This invention generally relates to the field of tools and equipment and in particular relates a double headed fastening stud for fender body.
BACKGROUND
[0002] The subject matter discussed in the background section should not be assumed to be prior art merely as a result of its mention in the background section. Similarly, a problem mentioned in the background section or associated with the subject matter of the background section should not be assumed to have been previously recognized in the prior art. The subject matter in the background section merely represents different approaches, which in and of themselves may also correspond to implementations of the claimed technology.
[0003] In conventional vehicle assemblies such as fender mounting systems, single-headed T-studs are commonly used for securing sheet metal or composite body components. However, these single headed fasteners may suffer from loss of clamping force over time, especially under conditions of vibration and dynamic loading during vehicle operation. The loosening effect may result in joint instability, requiring repeated torque checks, manual rework, and even unplanned line stoppages on the assembly floor. Furthermore, the gradual micro-movements of the stud within the sheet metal holes may lead to localized wear, reducing the long-term durability of the joint.
[0004] However, there are several fastening solutions exist for securing components to thin sheet metal or composite panels, each comes with inherent drawbacks that limit their suitability in high-vibration, high-volume assembly environments. Self-clinching nuts require high insertion forces and localized hardening of the sheet material, which may complicate manufacturability and limit application in softer substrates. Blind rivet nuts require specialized installation tools and are often not reusable or removable without damaging the surrounding structure. Thread-forming screws, though cost-effective, demand high drive torque and are known to induce material stress or even cracking in thin or brittle panels. Additionally, adhesive-backed washers introduce extra cure time into the assembly process and may degrade under elevated temperatures, humidity, or long-term mechanical cycling.
[0005] According to a patent application No. “US5435507A” titled as “Cable support” discloses an easily-installable support capable of accommodating a wide variety of fiber optic cables is disclosed. The fiber optic cable support uses a one-piece, variable diameter mechanism for cushioning and spacing the supported cable. The support is also contoured to increase the surface area available to contact a utility pole or other structure and includes one or more cleats or gains which provide additional contact strength by biting into and gripping wooden or similar poles. The support is designed to provide approximately constant compressive pressure to the supported sections of a length of cable and sufficient pressure to avoid the need to apply grit or other loose friction-increasing substances to the cushion interior. Because it is of relatively constant or slowly varying cross-section, the support can be die formed with minimal disruption of the fluid flow within the die.”
[0006] According to a patent application No. “CN2755341Y” titled as “Double-head screw against cross link” discloses a utility model relates to a screw bolt, particularly to a double-head anti-linking screw bolt. The utility model is characterized in that a concave or convex structure, which is used for tightening or loosening a tightening tool, is arranged on the end surface of the thread opening end of the screw bolt, namely the end surface of the thread opening end of the double-head screw bolt is provided the concave or convex structure. The utility model has the advantages that no linking is formed when the screw bolt or nuts are tightened or loosened, and the screw bolt can be tightened or loosened at one end of the screw bolt or one side of a work piece. The utility model has the advantages of novel structure and wide practicability.”
[0007] In none of the discussed prior arts describes clamping both inner and outer fender skins without using any special tooling, secondary processes and full compatibility with all plastic material grades is promised. Further, the prior art also falls short to ensure molding into plastic fenders & resisting vibrations and avoiding any multistage tightening.
 
OBJECTIVES OF THE INVENTION

[0008] An objective of the invention is to provide a double headed fastening stud for fender body of an automobile.
[0009] An another objective of the invention is to provide double-headed fastening stud that provides consistent and durable clamping of fender assemblies, particularly under conditions of operational vibration and thermal cycling of the automobile.
[0010] Furthermore, the objective of the present invention is to eliminate the torque loss associated with conventional single-headed T-studs, thereby reducing the need for repeated torque checks, rework, and unplanned assembly line stoppages.
[0011] Furthermore, the objective of the present invention is to provide the double-headed fastening stud that is simple to install using conventional press-fit methods, without requiring specialized tools, high insertion forces, or additional curing steps.
[0012] Furthermore, the objective of the present invention is to provide the double-headed fastening stud that improve fit and finish as under torqued fender joints may lead to poor fit and finish.
 
SUMMARY
[0014] The present invention relates to a double headed fastening stud for fender body of an automobile.
[0015] According to an aspect of the invention, a double headed fastening stud for fender body of an automobile, the stud comprising a cylindrical shank comprises a first head and a second head. Further, the first head of the cylindrical shank, is configured to accommodate a first surface of the fender body. Further, the second head of the cylindrical shank, is positioned to a second surface of the fender body, such that the first surface and the second surface of the fender body are clamped between the first head and second head of the stud to provide mechanical fixation.
 
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The accompanying drawings illustrate various embodiments of systems, methods, and embodiments of various other aspects of the disclosure. Any person with ordinary skills in the art will appreciate that the illustrated element boundaries (e.g., boxes, groups of boxes, or other shapes) in the figures represent one example of the boundaries. It may be that in some examples one element may be designed as multiple elements or that multiple elements may be designed as one element. In some examples, an element shown as an internal component of one element may be implemented as an external component in another, and vice versa. Furthermore, elements may not be drawn to scale. Non-limiting and non-exhaustive descriptions are described with reference to the following drawings. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating principles.
[0017] FIG. 1 illustrates a perspective view of a double headed fastening stud for fender body of an automobile, according to an embodiment of the present invention;
[0018] FIG. 2A and 2B illustrates a perspective view of the double headed fastening stud for fender body in upside orientation and downside orientation, respectively, according to an embodiment of the present invention;
[0019] FIG. 3A and 3B illustrates a front view and back view of a fender body, according to an embodiment of the present invention;
[0020] FIG. 4 illustrates a perspective view of integration of the double headed fastening stud to the fender body, according to an embodiment of the present invention; and
[0021] FIG. 5 illustrates a cross-section view of the double headed fastening stud (100) to the fender assembly, according to an embodiments of the present invention.
[0022] FIG. 6 illustrates a front view showing the dimensions of the double headed fastening stud of the fender body, according to an embodiment of the present invention.
[0023] FIG. 7 illustrates a flow chart of a method of coupling double headed fastening stud to the fender body of an automobile, according to an embodiment of the present invention.

DETAILED DESCRIPTION

[0024] Some embodiments of this disclosure, illustrating all its features, will now be discussed in detail. The words “comprising,” “having,” “containing,” and “including,” and other forms thereof, are intended to be equivalent in meaning and be open ended in that an item or items following any one of these words is not meant to be an exhaustive listing of such item or items or meant to be limited to only the listed item or items. It must also be noted that as used herein and in the appended claims, the singular forms “a,” “an,” and “the” include plural references unless the context clearly dictates otherwise.
[0025] Although any systems and methods similar or equivalent to those described herein can be used in the practice or testing of embodiments of the present disclosure, the preferred, systems and methods are now described. Embodiments of the present disclosure will be described more fully hereinafter with reference to the accompanying drawings in which like numerals represent like elements throughout the several figures, and in which example embodiments are shown. Embodiments of the claims may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. The examples set forth herein are non-limiting examples and are merely examples among other possible examples.
[0026] The present inventions relate to a double headed fastening stud for fender body of an automobile. Embodiments of the present invention comprises a cylindrical shank comprises a first head and a second head. Embodiments of the present invention comprises the first head of the cylindrical shank, is configured to accommodate a first surface of the fender body. Embodiments of the present invention comprises the second head of the cylindrical shank, is positioned to a second surface of the fender body, such that the first surface and the second surface of the fender body are clamped between the first head and second head of the stud to provide mechanical fixation.
[0027] FIG. 1 illustrates a perspective view of a double headed fastening stud (100) for fender body (108) of an automobile, according to an embodiment of the present invention;
[0028] FIG. 2A and 2B illustrates a perspective view of the double headed fastening stud (100) for fender body (108) in upside orientation and downside orientation, respectively, according to an embodiment of the present invention.
[0029] FIG. 3A and 3B illustrates a front view and back view of a fender body (108), according to an embodiment of the present invention.
[0030] FIG. 4 illustrates a perspective view of integration of the double headed fastening stud (100) to the fender body (108), according to an embodiment of the present invention.
[0031] FIG. 5 illustrates a cross-section view of the double headed fastening stud (100) to the fender assembly (108), according to an embodiments of the present invention.
[0032] FIG. 6 illustrates a front view showing the dimensions of the double headed fastening stud (100) of the fender body (108), according to an embodiment of the present invention.
[0033] In some embodiments, the double headed fastening stud (100) for fender body of an automobile is configured to provide robust, vibration-resistant clamping of work pieces suitable for plastic components that comprises automotive fenders or similar structures subject to mechanical stresses.
[0034] In some embodiments, the double headed fastening stud (100) for fender body of an automobile comprises a cylindrical shank (102). Further, the length of the double headed fastening stud (100) corresponds to 23mm. Further, the cylindrical shank (102) comprises a first head (104) and a second head (106). Further, the fender body (108) comprises a first surface (110) and a second surface (112).
[0035] In some embodiments, the cylindrical shank (102) extends longitudinally between two opposing ends. Further, the two opposing ends corresponds to a first end and a second end of the cylindrical shank (102). Further, the cylindrical shank (102) corresponds to a structural body of the stud (100). In one example, the cylindrical shank (102) comprises threads on its surface for fastening nut. Further, the threads with a 1 mm pitch are formed along the cylindrical portion of the cylindrical shank (102), as illustrated in FIG. 6. The threads enable the nut to be securely fastened onto the stud (100), providing mechanical retention and axial stability. The 1 mm pitch indicates the distance between adjacent thread peaks that defines the fineness of thread and affects how tightly or loosely the nut engages with the stud (100).
[0036] In some embodiments, the first end to the cylindrical shank (102) comprises a first head (104). Further, the first head (104) having a flange-like structure that configured to rest against the first surface (110) of the fender body (108) during installation. Further, the first head (104) and second head (106) of the stud (100) having a thickness of 1.5 mm, as illustrated in FIG. 6. In some embodiments, the fastening stud (100) is crafted with a material but not limited to stainless steel. Further, the material is configured to provide a corrosion resistance, mechanical strength, and thermal stability, making the fastening stud (100) well-suited for demanding environments such as automotive body assemblies. Further, the fender body (108) comprises first surface (110) and the second surface (112) showing in the front view and back view of the fender body (108) as illustrated in FIG. 3A and 3B. Further, the first surface (110) corresponds to the inner surface of the fender body (108) and the second surface (112) corresponds to the outer surface of the fender body (108).
[0037] In some embodiments, the second head (106) of the cylindrical shank (102) is integrally formed or machined at a spaced-apart location from the first head (104) along the cylindrical shank (102), such that the second head (106) is configured to engage the second surface (112) of the fender body (108). Further, an axial positioning of the second head (106) is predetermined based on a thickness of the fender body (108) in order to allow the first head (104) and the second to provide a dual-sided clamping action. For example, when the stud (100) is inserted through the 3 mm thick fender body (108), the first head (104) rests on one side of the fender body (108) and the second head (106) on the opposite side, thereby creating a dual-sided clamping effect. Further, a 3 mm axial spacing is present between the first head (104) and the second head (106), corresponding to the thickness of the fender body (108), to provide a proper axial alignment and enabling a dual-sided clamping action, as illustrated in FIG. 6.
[0038] In one example, the first head (104) and second head (106) of the double headed fastening stud (100) are configured as flat, disc-shaped flanges having a diameter greater than that of the cylindrical shank (102). Further, the increased flange diameter is configured to provide an enlarged bearing surface for distributing clamping force uniformly over the first surface (110) and second surface (112) of the fender body (108). The cylindrical shank (102) having a diameter of 8 mm at the base, specifically in the portion between the two heads (i.e. first head and second head) that ensures a firm structural interface with the component being mounted. Further, towards the upper portion of the cylindrical shank (102) of the stud, the diameter reduces to 6 mm, that is externally threaded to allow for nut fastening, as illustrated in FIG. 6.
[0039] In some embodiments, the first head (104) of the cylindrical shank (102), is configured to accommodate the first surface (110) of the fender body (108). The first head (104) of the cylindrical shank (102) configured to accommodate and engage the first surface (110) of the fender body (108). In some embodiments, the second head (106) of the cylindrical shank (102), is positioned to the second surface (112) of the fender body (108). Further, the positioning of the second head (106) of the cylindrical shank (102) to the second surface (112) of the fender body (108) is configured to provide mechanical fixation as illustrated in FIG. 4. The second head (106) of the cylindrical shank (102) is positioned along the length of the cylindrical shank (102) at the predefined axial distance from the first head (104), precisely corresponding to the thickness of the fender body (108) between its first surface (110) (i.e., inner surface) and second surface (112) (i.e. outer surface).
[0040] In some embodiments, the second head (106) is also configured as the flat flange that is machined with the cylindrical shank (102), and oriented to face the inner surface of the fender body (108) during installation. During press-fitting, the cylindrical shank (102) passes through a preformed aperture in the fender body (108) such that the second head (106) comes to rest against the second (inner) surface of the fender body (108). The positioning of the second head (106) ensure that the fender body (108) is sandwiched snugly between the first head (104) and the second head (106), with minimal axial play and no requirement for post-installation torque adjustments, as illustrated in FIG. 5.
[0041] In one example, double headed fastening stud (100) is press-fitted rather than screwed in. Therefore, there is no high insertion torque is needed. Further, only modest pressing force and a final tightening torque of approximately 12 Nm is required to secure any mating fastener or bracket. The press-fit also contributes to vibration resistance by eliminating gaps or play at the joint interface, helping maintain ≥ 98% of the original clamping force even under dynamic conditions.
[0042] In some embodiments, the double headed fastening stud (100) configured to provide a dual-sided mechanical fixation by clamping the first surface (110) and second surface (112) of the fender body (108) between the first head (104) and second head (106). The clamping action distributes the fastening load across both surfaces of the fender body (108), reducing the risk of deformation, fretting wear, or fatigue cracking, especially under dynamic loading such as road vibrations or thermal expansion cycles.
[0043] Further, double headed fastening stud (100) is configured to provide ≥ 98% of its initial tightening torque when subjected to prolonged vibration and dynamic loading. In some embodiments, the double headed fastening stud (100) is configured to provide a stable joint interface with improved torque retention, reduced dependency on secondary fastening elements (e.g., washers or backing plates), and enhanced resistance to loosening or displacement.
[0044] In one example, the second head (106) of the cylindrical shank (102) acts as a mechanical stop during the assembly process. The second head (106) is configured to prevent over-insertion of the stud (100) through the mounting hole by creating a defined axial limit. When the stud (100) is tightened either by a nut or threaded engagement, the second head (106) is configured to provide an axial locking by bracing against the second surface of the fender body (108). The second head (106) arrests further axial movement of the stud (100) once fully seated while positioned to an interface with the second surface (112) of the fender body (108). Further, the dimension and shape of the second of the cylindrical shank (102) is configured to resist rotational forces that may arise during the tightening of mating components such as nuts, brackets, or external fasteners applied from the outer side.
[0045] Functionally, the mechanical stop provided by the second head (106) may ensure that any tightening torque applied during the final assembly stage is fully transferred into the intended clamping load, rather than being dissipated in unintended rotational or axial movement of the stud (100). This results in a more consistent and predictable fastening outcome across multiple assemblies, reducing the risk of under-torqued or over-torqued joints. Furthermore, this design minimizes material creep or wear at the fastener interface over time, particularly in high-vibration environments such as automotive fender mounts. By anchoring the stud (100) firmly in position, the second head (106) enhances the mechanical robustness of the entire assembly and supports repeatable, high-speed fastening on automated production lines without requiring secondary fixtures or torque reaction tools.
[0046] FIG. 7 illustrates a flow chart of a method (700) of coupling double headed fastening stud (100) to the fender body (108), according to an embodiment of the present invention.
[0047] At operation 702, a first head (104) of a cylindrical shank (102) is accommodated to a first surface (110) of the fender body (108). the first end to the cylindrical shank (102) comprises a first head (104). Further, the first head (104) having a flange-like structure that configured to rest against or abut the first surface (110) of the fender body (108) during installation. In some embodiments, the fastening stud (100) is crafted with a material but not limited to stainless steel. Further, the material is configured to provide a corrosion resistance, mechanical strength, and thermal stability, making the fastening stud (100) well-suited for demanding environments such as automotive body assemblies.
[0048] At operation 704, second head (106) of the cylindrical shank (102) is positioned to a second surface (112) of the fender body (108). The second head (106) of the cylindrical shank (102) is integrally formed or machined at a spaced-apart location from the first head (104) along the cylindrical shank (102), such that the second head (106) is configured to engage the second surface (112) of the fender body (108).
[0049] At operation 706, the first surface (110) and the second surface (112) of the fender body (108) is clamped between the first head (104) and the second head (106) of the stud (100) to provide mechanical fixation. The clamping action distributes the fastening load across both surfaces of the fender body (108), reducing the risk of deformation, fretting wear, or fatigue cracking, especially under dynamic loading such as road vibrations or thermal expansion cycles. Further, double headed fastening stud (100) is configured to provide ≥ 98% of its initial tightening torque when subjected to prolonged vibration and dynamic loading. In some embodiments, the double headed fastening stud (100) is configured to provide a stable joint interface with improved torque retention, reduced dependency on secondary fastening elements (e.g., washers or backing plates), and enhanced resistance to loosening or displacement.
[0050] It has thus been seen the invention, the double headed fastening stud (100) for fender body (108) of an automobile as described. The double headed fastening stud (100) for fender body (108) of an automobile in any case could undergo numerous modifications and variants, all of which are covered by the same innovative concept; moreover, all of the details can be replaced by technically equivalent elements. In practice, the components used, as well as the numbers, shapes, and sizes of the components can be whatever according to the technical requirements. The scope of protection of the invention is therefore defined by the attached claims.
, Claims:We Claim:

1. A double headed fastening stud (100) for fender body (108) for an automobile, the double headed fastening stud (100) comprising:
a cylindrical shank (102) comprises a first head (104) and a second head (106),
wherein the first head (104) of the cylindrical shank (102), is configured to accommodate a first surface (110) of the fender body (108), and
wherein the second head (106) of the cylindrical shank (102), is positioned to a second surface (112) of the fender body (108), such that the first surface (110) and the second surface (112) of the fender body (108) are clamped between the first head (104) and second head (106) of the stud (100) to provide mechanical fixation.

2. A double headed fastening stud (100) for fender body (108) as claimed in claim 1, wherein the first head (104) and the second head (106) of the stud (100) are flat flanges having a thickness of 1.5mm.

3. A double headed fastening stud (100) for fender body (108) as claimed in claim 1, wherein the second head (106) is machined on the cylindrical shank (102) and spaced apart from the first head (104) by a portion of the cylindrical shank (102), such that the spacing corresponds to the thickness of a fender body (108) of 3 mm.

4. A double headed fastening stud (100) for fender body (108) as claimed in claim 1, wherein the cylindrical shank (102) having a diameter of 8 mm at a base portion located between the first head (104) and the second head (106), and reduces to 6 mm near a threaded region at the top of the cylindrical shank (102).

5. The double headed fastening stud (100) for fender body (108) as claimed in claim 1, wherein the fastening stud (100) is press-fit between the fender body (108) and the cylindrical shank (102) to generate a clamping force that is sufficient to withstand at operational vibrations.

6. The double headed fastening stud (100) for fender body (108) as claimed in claim 1, wherein the fastening stud (100) is configured to prevent axial loosening under vibrational conditions.

7. The double headed fastening stud (100) for fender body (108) as claimed in claim 1, wherein the second head (106) of the cylindrical shank (102) is configured to provide a mechanical stop to eliminate relative rotation and displacement during tightening of the fender body (108).

8. A method (600) of coupling double headed fastening stud (100) to the fender body (108) of an automobile, the method (600) comprises:
accommodating a first head (104) of a cylindrical shank (102) to a first surface (110) of the fender body (108);
positioning a second head (106) of the cylindrical shank (102) to a second surface (112) of the fender body (108); and
clamping the first surface (110) and the second surface (112) of the fender body (108) between the first head (104) and the second head (106) of the stud (100) to provide mechanical fixation