CROSS-REFERENCE TO RELATED APPLICATIONS

This Application claims priority to U.S. Provisional Application 62/659,012, entitled “ADVANCED THIN-WALLED STRUCTURE FOR ENHANCED CRASH PERFORMANCE” filed Apr. 17, 2018, the entire content of which is hereby incorporated by reference.

BACKGROUND

Technical Field

The present disclosure relates to a thin-walled structure for the crash zones of a vehicle, otherwise known as a crash can. More particularly, the present disclosure relates to a crash can of a vehicle that absorbs energy upon impact in an efficient way.

Description of Related Art

Passenger vehicles such as cars, trucks or the like typically include metal structures at the front of the frame with which to absorb the energy of an impact. These structures are typically a square, single cell tube directly mounted to the front of the frame of the vehicle, which will deform in a stable manner and absorb energy during an impact, e.g., collision.

SUMMARY

In some embodiments a crash can for a vehicle includes a multi-cell structure that includes at least four hollow cuboids, each defined by four walls. The four walls of the hollow cuboids meet at 90 degree angles and at least two of the cuboids share a wall.

In some embodiments a crash can for a vehicle includes a multi-cell structure that includes a hollow cuboid and four hollow isosceles trapezoidal prisms. The hollow cuboid has four walls and the four hollow isosceles trapezoidal prisms each have a long base, a short base, and two legs. The four hollow isosceles trapezoidal prisms are arranged around the hollow cuboid such that the long base of each hollow isosceles trapezoidal prism shares one of the walls of the hollow cuboid.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example of how a crash can may be used in a vehicle according to some embodiments.

FIG. 2A illustrates an example of a crash can undergoing stable deformation.

FIG. 2B illustrates examples of a crash can undergoing unstable deformation.

FIG. 3A illustrates a crash can according to some embodiments.

FIG. 3B illustrates a crash can according to some embodiments.

FIG. 4A illustrates a crash can according to some embodiments.

FIG. 4B illustrates a cross section of a hollow isosceles trapezoidal prism according to some embodiments.

FIG. 5 illustrates a cross section of a hollow isosceles trapezoidal prism used to calculate various measurements.

Embodiments of the present disclosure and their advantages are best understood by referring to the detailed description that follows. It should be appreciated that like reference numerals are used to identify like elements illustrated in one or more of the figures, wherein showings therein are for purposes of illustrating embodiments of the present disclosure and not for purposes of limiting the same.

DETAILED DESCRIPTION OF THE DISCLOSURE

The present disclosure provides examples of systems and techniques for providing a structure (e.g., a crash can, rail, etc.) to absorb energy via axial progressive folding deformation during a collision. Exemplary structures disclosed are capable of absorbing more energy in a more efficient manner during a vehicle collision than conventional single cell structures. The energy absorption of the structures is provided by a stable and efficient method of progressive collapse that increases the amount of energy that will be absorbed. Exemplary structures provided herein also have manufacturing advantages in terms of the process and materials that can be used. These manufacturing advantages result in a structure that increases energy absorption per unit mass, or the specific energy absorption of the structure, while being lighter than conventional structures to allow for a more even distribution of the weight of a vehicle and a lighter structure in the front end or other various desired portions of the vehicle. The advantages in material and weight allow for vehicles that are designed to be lighter and more energy or fuel efficient to maintain or improve on the safety of vehicle occupants and critical vehicle components (e.g., a high voltage battery) by increasing the amount of energy absorbed by the crash structure in a collision. Accordingly, vehicles seeking to shed weight or increase the specific energy in a collision zone may be both stylish and safe and thus make the vehicle more commercially feasible.

Reference will now be made in detail to specific aspects or features, examples of which are illustrated in the accompanying drawings. Like reference numerals refer to corresponding parts throughout the figures.

FIG. 1 illustrates an example of how crash can 103 can be mounted to the front structure of a vehicle 100. The structure generally includes a frame 101, a bumper 102, and a crash can 103. The crash can 103 may be connected to the frame 101 and bumper 102 with any acceptable fastening method, for example with welds, rivets, or other known fastening devices. The crash can 103 is placed in between the frame 101 and the bumper 102, with each end of the crash can 103 attached to either the frame 101 or the bumper 102. Accordingly, when the front structure of the vehicle 100 is involved in a collision, the bumper 102 will first receive the force of the collision. This force is transferred from the bumper 102 to the crash can 103, which is designed to deform and absorbs energy. In this manner, the amount of energy received by frame 101 during the collision is reduced. Thus, occupants of vehicle 100 will be less likely to be injured and critical vehicle components (e.g., a high voltage battery) will be less likely to be damaged from the force of collision or the deforming metal of frame 101 during the collision.

FIG. 2A illustrates how crash can 103 may deform when subjected to the force of a collision. Crash can 103 absorbs energy via plastic deformation. Crash can 103 absorbs the most energy by maximizing the plastic deformation through progressive buckling. Progressive buckling is a stable buckling mode characterized by top down, regular folding of the structure as seen in FIG. 2A. In contrast, non-progressive buckling drastically reduces the amount of energy that crash can 103 can absorb. Examples of non-progressive buckling can be seen in FIG. 2B. Accordingly, it is desired that crash can 103 will maximize plastic deformation through progressive buckling in order to absorb as much energy as possible in a stable progressive manner.

In some embodiments a crash can described herein includes a multi-cell structure that includes at least four hollow cuboids each defined by four walls that meet at 90 degree angles and at least two of the hollow cuboids share a wall. In some embodiments the crash can includes a multi-cell structure that includes nine hollow cuboids. In some embodiments the crash can is comprised of aluminum alloy and is made of a piece of extruded aluminum alloy. In some embodiments the thickness of the walls is between 1 mm and 3.5 mm. In some embodiments the length of each wall is between 26 mm and 38 mm. In some embodiments the crash can also include four outside walls that meet at 90 degree angles to form four corners. In some embodiments the four corners are rounded.

In some embodiments a crash can includes a multi-cell structure that includes a hollow cuboid having four walls, and four hollow isosceles trapezoidal prisms having a long base, a short base and two legs. In some embodiments the four hollow isosceles trapezoidal prisms are arranged around the hollow cuboid such that each of the hollow isosceles trapezoidal prisms shares its long base with one of the walls of the hollow cuboid. In some embodiments the cross section of the crash can forms a substantially cross shape. In some embodiments the short base of each hollow isosceles trapezoidal prism joins the legs such that an obtuse corner angle is created at each junction. In some embodiments the obtuse corner angle is between 90 degrees and 95 degrees. In some embodiments the long base of each hollow isosceles trapezoidal prism joins the legs such that an acute corner angle is created at each junction. In some embodiments the acute corner angle is between 85 degrees and 90 degrees. In some embodiments the crash can is comprised of an aluminum alloy. In some embodiments the crash can is comprised of an extruded piece of aluminum alloy. In some embodiments each of the walls of the hollow cuboid, and the long base, the short base and the two legs of each hollow isosceles trapezoidal prism are between 1 mm and 3.5 mm thick. In some embodiments the length of each of the walls of the hollow cuboid is between 26 mm and 38 mm. In some embodiments the length of the legs of each of the hollow isosceles trapezoidal prisms is the same as the length of the walls of the hollow cuboid. In some embodiments the length of the legs of each of the hollow isosceles trapezoidal prisms is between 26 mm and 38 mm. In some embodiments the hollow isosceles trapezoidal prism also has a height measured between the long base and the short base. In some embodiments the height is the same as the length of the long base of the hollow isosceles trapezoidal prism. In some embodiments the outside corner where each of the short bases meets one of the legs is rounded.