Description:FIELD OF INVENTION

[001] The present invention relates to field of automotive technology. Particularly, the present disclosure pertains to an automotive crash box, which is conventionally inserted between a bumper and load-bearing parts of the body in a motor vehicle, to absorb energy while deforming during a collision, and thereby protect the load-bearing parts against deformation.
BACKGROUND OF THE INVENTION

[002] A crash box is a crucial structural component in vehicles, designed to absorb impact energy during collisions and protect passengers by minimizing the forces transmitted to the cabin. Positioned between the bumper and the vehicle’s mainframe, the crash box deforms upon impact, converting kinetic energy into plastic deformation energy. This mechanism enhances crashworthiness and occupant safety, making the crash box a standard feature in modern automotive designs.

[003] However, despite advancements in material selection and structural optimization, existing crash boxes face significant limitations. Many designs exhibit low energy absorption per unit, limiting their effectiveness in mitigating collision forces. Additionally, the lack of scalability in these designs makes it difficult to adapt them for different vehicle types or varying energy absorption requirements. Manufacturing challenges, including complex geometries and advanced production techniques, further add to the difficulty and cost of mass production. Moreover, the intricate design of current crash boxes complicates assembly processes and integration with other vehicle components, resulting in high assembly lead times. Tailoring crash box designs to meet specific energy absorption needs often involves multiple design iterations, which increases development time and costs.

[004] A Germany patent DE102004039592B4 titled “crash box” discloses a crash box. The crash box has an outward directed material formation or wall thickening in the transition region between a deformation section and an attachment section that forms a stop that contacts the end face of the longitudinal support. The stop contacts the long sides and/or the transverse sides of the longitudinal support. However, the intricate design of cited crash boxes complicates assembly processes and integration with other vehicle components, resulting in high assembly lead times. Furthermore, tailoring the crash box designs of the cited invention to meet specific energy absorption needs often involves multiple design iterations, which increases development time and costs.

[005] In order to overcome the problem associated with state of arts, there is a need for the development of an efficient automotive crash box for vehicle that can overcome the aforesaid limitations in a more efficient manner.

OBJECTIVE OF THE INVENTION

[006] The primary objective of the present invention is to provide an automotive crash box for vehicles.

[007] Another objective of the present invention is to provide high crash energy absorption per Unit Weight in high speed and low-speed vehicle collisions.

[008] Another objective of the present invention is to provide a crash box that is adaptable to different lengths to meet specific energy absorption requirements.

[009] Another objective of the present invention is to provide Simplified construction of crash box that provides ease of manufacturing for cost-effective, large-scale production.

[0010] Another objective of the present invention is to provide a crash box that provides higher average crush load sustained throughout the stroke length of crash box.

[0011] Yet another objective of the present invention is to increase deceleration time.

[0012] Yet another objective of the present is to reduce complexity in manufacturing and assembly thereby reducing lead time.

[0013] Yet another objective of the present is to eliminate design iterations for different energy absorption requirements by reducing dependency on complex architectures making the system more cost-effective to produce and maintain.

[0014] Other objectives and advantages of the present invention will become apparent from the following description taken in connection with the accompanying drawings, wherein, by way of illustration and example, the aspects of the present invention are disclosed.

BRIEF DESCRIPTION OF DRAWINGS

[0015] The present invention will be better understood after reading the following detailed description of the presently preferred aspects thereof with reference to the appended drawings, in which the features, other aspects and advantages of certain exemplary embodiments of the invention will be more apparent from the accompanying drawing in which:

[0016] Figure 1 illustrates an assembled view of the crash box with bumper beam;

[0017] Figure 2 illustrates a exploded view of the crash box;

[0018] Figure 3 illustrates a perspective view of the crash box with dimensions;

[0019] Figure 4 illustrates a cut section view of the crash box with dimensions;

[0020] Figure 5 illustrates an cross-sectional view of the crash box with bumper beam;

[0021] Figure 6 illustrates a deformation and crush pattern of the crash box;

[0022] Figure 7 illustrates perspective view of the crash box assembly with welding details; and.

[0023] Figure 8 illustrates a graph showing the Energy Absorption Graphs of different components of crash box during Full Frontal crash simulation

[0024] Figure 9 illustrate a graph showing average crash load along the stroke length of a crash box.

SUMMARY OF THE INVENTION

[0025] The present invention relates to an automotive crash box. The system comprising: at least two c-shaped bracket assembly; and one or more rectangular tubular section connected between the at least two c-shaped bracket assembly through a full seam weld technique, wherein the c-shaped bracket assembly are welded at a predefined distance from a center of the rectangular tubular section so as to increase load distribution area while maintaining stability around the one or more rectangular tubular section. The crash box undergoes plastic deformation during crashes and absorb crash energy and increase deceleration time. The crash boxes are generally connected between the bumper beam and crash rail of the vehicle chassis. After welding the at least two c-shaped brackets and the rectangular tubular section, the crash box is placed between the bumper beam and crash rail plate and welded together.

[0026] The present invention also provides a method for construction of an automotive crash box. The method comprising steps of: placing of a first c-shaped bracket assembly on a top of a rectangular tubular section; placing of a second c-type channel on a bottom of the rectangular tubular section; welding of the first c-shaped bracket assembly to the top of the rectangular tubular section at a predefined distance from a center of the rectangular tubular section; and welding of the second c-shaped bracket assembly to the bottom of the rectangular tubular section at the predefined distance from the center of the rectangular tubular section.

DETAILED DESCRIPTION OF INVENTION

[0027] The following detailed description and embodiments set forth herein below are merely exemplary out of the wide variety and arrangement of instructions which can be employed with the present invention. The present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. All the features disclosed in this specification may be replaced by similar other or alternative features performing similar or same or equivalent purposes. Thus, unless expressly stated otherwise, they all are within the scope of the present invention.

[0028] Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope of the invention. In addition, descriptions of well-known functions and constructions are omitted for clarity and conciseness.

[0029] The terms and words used in the following description and claims are not limited to the bibliographical meanings but are merely used 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 are provided for illustration purpose only and not for the purpose of limiting the invention.

[0030] It is to be understood that the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise.

[0031] It should be emphasized that the term “comprises/comprising” when used in this specification is taken to specify the presence of stated features, integers, steps, or components but does not preclude the presence or addition of one or more other features, integers, steps, components, or groups thereof.

[0032] Accordingly, the present invention relates to field of automotive technology. Particularly, the present disclosure pertains to an automotive crash box, which is conventionally inserted between a bumper and load-bearing parts of the body in a motor vehicle, to absorb energy while deforming during a collision, and thereby protect the load-bearing parts against deformation.

[0033] In an embodiment, as shown in Figure 1 and Figure 2, an automotive crash box (100) for Vehicle, comprising: at least two c-shaped bracket assembly (4,6); and one or more rectangular tubular section (5) connected between the at least two c-shaped bracket assembly (4, 6) through a full seam weld (7a, 7b) technique as shown in Figure 7, wherein the c-shaped bracket assembly (4, 6) are welded at a predefined distance from a center of the rectangular tubular section (5) so as to increase load distribution area while maintaining stability around the one or more rectangular tubular section (5).

[0034] In an exemplary embodiment of the present invention, the full seam weld (7a, 7b) comprises of a throat diameter of at least 6 mm and the predefined distance is at least 10mm.

[0035] In another exemplary embodiment of the present invention, the full seam welding technique is selected from a group consisting of such as, but not limited to, Tungsten Inert Gas welding, electric arc welding, and Metal Inert Gas welding, and the alike.

[0036] In an embodiment, the invention encompasses creation of an enhanced automotive crash box (100) for - vehicles. The crash box (100) undergoes plastic deformation during crash and absorb crash energy and increase deceleration time. The crash boxes are connected between a bumper beam (102) and a load bearing part of the vehicle chassis. In an exemplary embodiment, the load bearing part may be selected from such as, but not limited to, crash rail, and the alike.

[0037] The crash box is formed by connecting at least two C- shaped bracket assembly (4), and (6) (as shown in Figure 1, 2) to one or more rectangular tubular section (5). In an exemplary embodiment, the c-shaped bracket assembly (4, 6) and the rectangular tubular section (5) may be constructed with weld using full seam welding selected from such as, but not limited to, Tungsten Inert Gas welding, electric arc welding, and Metal Inert Gas welding, and the alike. In a preferred embodiment, the c-shaped bracket assembly (4, 6) and the rectangular tubular section (5) are made of steel material (YST 240) using 6mm seam lap welding (as shown in Figure 7). Furthermore, the C-shaped brackets (4 & 6) and the rectangular section (5) can be further optimized by using materials with different strengths.

[0038] The structure of crash box may be used in application such as, but not limited to, Bumper beam, and the alike.

[0039] In an exemplary embodiment, as illustrated in Figure 3 and 4, the crash box (100) is 270mm long (3a) and 120mm height (3b) and 85mm wide (3c) with tubular section of 40 mm height (4a) and 80mm width(3d) and c type channel section with flange of 48mm long (4b) (4c).

[0040] In another exemplary embodiment, the C shaped bracket assembly (4, 6) are positioned by offset of 10mm from center of tubular section (4d). After welding, the crash box (100) is placed between the bumper beam (102) and crash rail plate and welded together (as shown in Figure 1).

[0041] In yet another exemplary embodiment, the one or more rectangular tubular section (5) and at least two c-shaped bracket assembly (4,6) are constructed of steel plate of a predefined thickness with yield strength of at least 240 MPa, wherein the predefined thickness of 2-4mm. The thickness of the upper c-shaped bracket (4) can be equal to, greater than, or less than the thickness of the lower c-shaped bracket (6).

[0042] After Successful implementation of the crash box (100), the crash box (100) deforms during crash and the amount of crash force produced during collision is measured throughout the stroke length of crash box (as shown in Fig 9).

EXPERIMENTAL DATA

[0043] The crash box (100) starts with lower peak crash loads of 80KN at the start to enhance crumpling initiation and reaches peak loads of 350KN and absorbs effective average crush load of 200.57KN along the length of the crash box as shown in Figure 9. Energy is absorbed by crash boxes; it absorbs 17KJ each for top and bottom members (4, & 6) and 26KJ for middle tubular member (5) (as shown in Figure 8). The deformation pattern of the crash box at different time interval of crash event at 12ms (6a), 19ms (6b) and 26ms (6c) of crash event is found (as shown in Figure 6). Bumper beam (102) is also implemented with crash box design with two channel members (1 &3) connected to tubular member (2) with similar dimension but with increased length as shown in Figure 1.

[0044] In an embodiment, the present invention also provides method for construction of an automotive crash box, comprises the following steps:-
• placing of a first c-shaped bracket assembly (4) on a top of a rectangular tubular section (5);
• placing of a second c-type channel (6) on the bottom of the rectangular tubular section (5);
• welding of the first c-shaped bracket assembly (4) to the top of the rectangular tubular section (5) at a predefined distance from a center of the rectangular tubular section (5); and
• welding of the second c-shaped bracket assembly (6) to the bottom of the rectangular tubular section (5) at the predefined distance from the center of the rectangular tubular section (5).

[0045] In an exemplary embodiment of the present invention, the welding technique is selected from a group consisting of such as, but not limited to, Tungsten Inert Gas welding, electric arc welding, and Metal Inert Gas welding, and the alike.

[0046] In another exemplary embodiment, the crash box (100) is 270mm long (3a) and 120mm height (3b) and 85mm wide (3c) with tubular section of 40 mm height (4a) and 80mm width(3d) and c shaped bracket assembly (4,6) with flange of 48mm long (4b) (4c).

[0047] In yet another exemplary embodiment, the C shaped bracket assembly (4, 6) are positioned by offset of 10mm from center of tubular section (4d). After welding, the crash box (100) is placed between the bumper beam (102) and crash rail plate and welded together (as shown in Figure 1).

[0048] The crash box (100) is formed by connecting at least two C- shaped bracket assembly (4), and (6) (as shown in Figure 1, 2) to one or more rectangular tubular section (5). In a preferred embodiment, the c-shaped bracket assembly (4,6) and the rectangular tubular section (5) are made of steel material (yst 240 ) using 6mm seam lap welding (as shown in Figure 7). In a preferred embodiment, the one or more rectangular tubular section (5) and at least two c-shaped bracket assembly (4,6) are constructed of steel plate of a predefined thickness with yield strength of steel at least 240 MPa, wherein the predefined thickness may be of 2mm.

[0049] While this invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the scope of the appended claims.
, Claims:1. An automotive crash box (100) for Vehicle, comprising:
• at least two c-shaped bracket assembly (4,6);
• one or more rectangular tubular section (5) connected between the at least two c-shaped bracket assembly (4, 6) through a full seam weld (7a, 7b) technique, wherein the c-shaped bracket assembly (4, 6) are welded at a predefined distance from a center of the rectangular tubular section (5) so as to increase load distribution area while maintaining stability around the one or more rectangular tubular section (5).

2. The automotive crash box (100) as claimed in claim 1, wherein the one or more rectangular tubular section (5) and at least two c-shaped bracket assembly (4,6) are constructed of steel plate of a predefined thickness with yield strength of steel (YST) of at least 240 MPa.

3. The automotive crash box (100) as claimed in claim 3, wherein the thickness of the upper c-shaped bracket (4) can be equal to, greater than, or less than the thickness of the lower c-shaped bracket (6).

4. The automotive crash box (100) as claimed in claim 1, wherein the full seam weld (7a, 7b) comprises of a throat diameter of at least 6 mm.

5. The automotive crash box (100) as claimed in claim 1, wherein the predefined distance is at least 10mm.

6. The automotive crash box (100) as claimed in claim 1, wherein the full seam welding technique is selected from Tungsten Inert Gas welding, electric arc welding, and Metal Inert Gas welding.

7. A method for construction of an automotive crash box, comprising:
• placing of a first c-shaped bracket assembly (4) on a top of a rectangular tubular section (5);
• placing of a second c-type channel (6) on the bottom of the rectangular tubular section (5);
• welding of the first c-shaped bracket assembly (4) to the top of the rectangular tubular section (5) at a predefined distance from a center of the rectangular tubular section (5); and
• welding of the second c-shaped bracket assembly (6) to the bottom of the rectangular tubular section (5) at the predefined distance from the center of the rectangular tubular section (5);

8. The method as claimed in claim 7, wherein the one or more rectangular tubular structure (5) and at least two c-shaped bracket assembly (4,6) are constructed of steel plate of a predefined thickness with yield strength of steel (YST) of at least 240 MPa.

9. The method as claimed in claim 8, wherein the predefined distance is at least 10mm.

10. The method as claimed in claim 7, wherein the welding comprises of a throat diameter of at least 6 mm.