Vehicle side sill

Abstract

A vehicle side sill according to one embodiment of the present invention aims to improve the collision energy absorption efficiency of the side sill and achieve weight reduction, and includes a side sill frame extending in a first direction and including a hollow portion, and a reinforcing frame disposed in the hollow portion and including a plurality of unit patterns extending in the first direction, wherein the unit pattern portions include a flat portion disposed on a plane consisting of the first direction and a second direction intersecting the first direction, and an inclined portion disposed subsequent to the flat portion and inclined relative to the flat portion, and at least one of the flat portion or the inclined portion includes a bent portion extending in the second direction.

Description

[Technical Field]

[0001] The present invention relates to a side sill for a vehicle. [Background technology]

[0002] It is to be understood that the material set forth in this section is merely provided as background information for the present invention and may not constitute prior art.

[0003] Vehicle side sills play a role in protecting passengers by absorbing collision energy in the event of a side collision.

[0004] Side sills applied to environmentally friendly vehicles such as electric vehicles protect not only passengers but also the battery located underneath. Because the battery is relatively large compared to other components of the vehicle, the side space of a vehicle equipped with a battery is relatively narrow compared to a vehicle equipped with an internal combustion engine.

[0005] Therefore, the side sill applied to the environmentally friendly vehicle should be able to absorb maximum collision energy in a narrow space and should have minimum weight to improve the energy efficiency of the environmentally friendly vehicle.

[0006] For this reason, aluminum extrusion materials have been used for environmentally friendly vehicle side sills, but there is still a demand for improved collision energy absorption capacity and weight reduction. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Korean Utility Model Publication No. 20-1998-0043143 (1998.09.25) Summary of the Invention [Problem to be solved by the invention]

[0008] An object of the present invention is to improve the collision energy absorption efficiency of a side sill and to achieve weight reduction.

[0009] An object of the present invention is to increase the rigidity of a side sill and reduce manufacturing costs. [Means for solving the problem]

[0010] As one aspect for achieving the above-mentioned object, a vehicle side sill according to one embodiment of the present invention includes a side sill frame extending in a first direction and including a hollow portion, and a reinforcing frame disposed in the hollow portion and including a plurality of unit patterns extending in the first direction, wherein the unit patterns include a surface portion disposed on a plane consisting of the first direction and a second direction intersecting the first direction, and an inclined portion subsequent to the flat portion and disposed at an angle relative to the surface portion, and at least one of the flat portion or the inclined portion includes a bent portion extending in the second direction.

[0011] The planar portion may include a first planar portion arranged in the first direction and a second planar portion arranged in the first direction and at a lower position than the first planar portion, and the inclined portion may include a first inclined portion arranged at an incline following the first planar portion, and a second inclined portion arranged at an incline following the second planar portion.

[0012] The bent portion may be formed in a central portion of the first flat portion, the first inclined portion, the second flat portion, or the second inclined portion.

[0013] The bent portion may have two or more consecutive bent shapes, forming a wavy shape.

[0014] The bent portion may be formed to protrude or recess in a direction perpendicular to a flat surface of the first flat portion, the second flat portion, the first inclined portion, or the second inclined portion.

[0015] The first and second flat portions may be spaced apart from the side sill frame.

[0016] The reinforcing frame may also be made of a single steel plate.

[0017] The first flat portion, the second flat portion, the first inclined portion, and the second inclined portion may be formed as a unit pattern, and the unit pattern may be repeated in the first direction.

[0018] Furthermore, the length of the first flat portion and the second flat portion in the first direction of the side sill frame may be a value between 40 mm and 70 mm.

[0019] Furthermore, the angle formed by an extension line of the first flat portion or the second flat portion and the first inclined portion or the second inclined portion may be a value between 45° and 75°.

[0020] The thickness of the strengthening frame may be 1.8 mm to 2.2 mm.

[0021] The reinforcing frame may be made of a steel material having the same or higher tensile strength or yield strength than the side sill frame, and the reinforcing frame may have a tensile strength of 1180 MPa or more and a yield strength of 850 MPa to 1060 MPa. [Effects of the Invention]

[0022] According to the present invention, the collision energy absorption efficiency of the side sill can be improved, and the weight of the side sill can be reduced.

[0023] According to the present invention, the rigidity of the side sill can be increased and the manufacturing cost can be reduced. [Brief explanation of the drawings]

[0024] [Figure 1] 1 is a perspective view of a vehicle side sill according to an embodiment of the present invention; [Figure 2] 1 is a perspective view of a reinforcing frame according to an embodiment of the present invention; [Figure 3] FIG. 2 is a cross-sectional view taken along line II' in FIG. [Figure 4] 2 is a cross-sectional view of a portion of a vehicle side sill according to another embodiment of the present invention taken along line II' in FIG. 1. FIG. [Figure 5] 2 is a cross-sectional view of a portion of a vehicle side sill according to another embodiment of the present invention taken along line II' in FIG. 1. FIG. [Figure 6] FIG. 10 is a cross-sectional view showing a reinforcing frame for a vehicle side sill according to another embodiment of the present invention. [Figure 7] FIG. 10 is a cross-sectional view showing a reinforcing frame for a vehicle side sill according to another embodiment of the present invention. [Figure 8] 10 is a cross-sectional view of a reinforcement frame according to yet another embodiment of the present invention; [Figure 9] 1 is a cross-sectional view of an existing vehicle side sill. [Figure 10] 10 is a load-displacement diagram of the vehicle side sill of FIG. 1 and the vehicle side sill of FIG. 9. DETAILED DESCRIPTION OF THE INVENTION

[0025] To facilitate understanding of the description of the embodiments of the present invention, elements denoted with the same reference numerals in the accompanying drawings are the same elements, and related components among components that perform the same function in each embodiment are denoted with the same or extended numerals.

[0026] In order to clarify the gist of the present invention, descriptions of elements and techniques well known in the prior art will be omitted, and the present invention will be described in detail below with reference to the accompanying drawings.

[0027] However, it is clear that the concept of the present invention is not limited to the examples presented, and that other forms in which specific components are added, modified, or deleted may be proposed by those skilled in the art, and these also fall within the scope of the same concept of the present invention.

[0028] Fig. 1 is a perspective view of a vehicle side sill according to an embodiment of the present invention, Fig. 2 is a perspective view of a reinforcing frame according to an embodiment of the present invention, and Fig. 3 is a cross-sectional view taken along line II' in Fig. 1.

[0029] A vehicle side sill 100 according to an embodiment of the present invention may include a side sill frame 110 having a hollow portion 113 and a reinforcing frame 120 positioned in the hollow portion 113 .

[0030] The side sill frame 110 has a hollow portion 113 formed therein, and the hollow portion 113 may be formed continuously in a first direction (Y-axis direction) that is the length direction of the side sill frame 110.

[0031] The side sill frame 110 may be formed by combining a first side sill frame 111 and a second side sill frame 112 together.

[0032] The first side sill frame 111 and the second side sill frame 112 may have bent portions and flanges formed at both ends thereof, and a coupling portion 114 may be formed by coupling the flanges formed on the first side sill frame 111 and the second side sill frame 112 to each other by abutting against each other.

[0033] The connecting portion between the first side sill frame 111 and the second side sill frame 112, where the connecting portion 114 is formed, may be formed by joining. However, the connecting method is not limited thereto and includes any method by which the first side sill frame 111 and the second side sill frame 112 are connected and fixed.

[0034] In this application, the term "joining" can be used to include all joining methods, such as arc welding, resistance welding, adhesive bonding, friction bonding, FDS (Flow Drill Screw) bonding, rivet bonding, and laser welding.

[0035] The first side sill frame 111 and the second side sill frame 112 may be formed by bending a single plate material. That is, the first side sill frame 111 and the second side sill frame 112 may each be processed as a single plate material.

[0036] In addition, the first side sill frame 111 and the second side sill frame 112 may be formed by extrusion.

[0037] As an example, the first side sill frame 111 may be extruded into an angular shape, and the second side sill frame 112 may be extruded into an angular shape, and each may be molded.

[0038] As yet another example, the first side sill frame 111 and the second side sill frame 112 may be extruded as a single unit and molded at one time.

[0039] When the first side sill frame 11 and the second side sill frame 112 are joined together, a hollow portion 113 may be formed inside.

[0040] The reinforcing frame 120 may be disposed in the hollow portion 113 and may be formed continuously in a first direction, which is the length direction of the side sill frame 110. At least a portion of the reinforcing frame 120 may be formed parallel to a second direction (X-axis direction), which is the width direction of the vehicle, from a point in the first direction. The reinforcing frame 120 may include a plurality of unit patterns U.

[0041] In one embodiment of the present invention, the unit pattern U included in the reinforcement frame 120 may include flat portions 121 and 122 arranged on a plane consisting of the first direction and a second direction intersecting the first direction, and inclined portions 123 and 124 arranged adjacent to the flat portions 121 and 122 and inclined relative to the flat portions 121 and 122.

[0042] For example, the flat portions 121 and 122 may include a first flat portion 121 and a second flat portion 122, and the inclined portions 123 and may include a first inclined portion 123 and a second inclined portion .

[0043] The side sill frame 110 may include a first flat portion 121 positioned parallel to the first direction, a first inclined portion 123 disposed inclined from the first flat portion 121, a second flat portion positioned lower than the first inclined portion 123, and a second inclined portion 124 formed inclined from the second flat portion 122. The second inclined portion 124 may be formed symmetrically with the first inclined portion 123.

[0044] In this case, the first flat portion 121 and the second flat portion 122 may be portions formed parallel to the second direction from a point in the first direction.

[0045] The strengthening frame 120 may have a first flat portion 121, a second flat portion 122, a first inclined portion 123, and a second inclined portion 124, which are flat portions and inclined portions, formed repeatedly.

[0046] By forming the side sill frame 110 in this manner, it is possible to improve the impact absorption effect of the side sill frame 110 against a side impact while achieving a lightweight structure.

[0047] The first and second planar portions 121 and 122 are not limited to a specific length, but as an example, the length of the first and second planar portions 121 and 122 in the first direction of the side sill frame 110 may be 40 mm to 70 mm. If the length of the first and second planar portions 121 and 122 in the first direction is less than 40 mm, the period of the repeated unit pattern U of the unit section of the reinforcing frame 120 becomes shorter, which increases the amount of material used and the weight, which may have a negative impact on weight reduction.

[0048] If the length in the first direction of the first planar portion 121 and the second planar portion 122 exceeds 70 mm, the resistance of the first planar portion 121 and the second planar portion 122 to deformation may decrease, and since the period of the repeated unit pattern U of the reinforcement frame 120 becomes longer, the resistance portion that resists deformation may decrease, resulting in a decrease in the efficiency of collision energy absorption.

[0049] Furthermore, the first flat portion 121 and the second flat portion 122 may have the same length in the first direction, but are not limited to the same length.

[0050] As an example, the thickness of the strengthening frame 120 may be 1.8 mm to 2.2 mm.

[0051] If the thickness of the reinforced frame 120 is less than 1.8 mm, there is a possibility that the performance of the collision energy absorption efficiency will be reduced due to a decrease in the resistance to deformation of the reinforced frame 120. If the thickness of the reinforced frame 120 is more than 2.2 mm, there is a possibility that the weight of the reinforced frame 120 will increase, thereby reducing the effect of weight reduction.

[0052] According to an embodiment of the present invention, the side sill frame 110, the first flat portion 121, and the second flat portion 122 may be spaced apart from each other.

[0053] The reinforcement frame 120 may be disposed spaced apart from the upper and lower surfaces of the side sill frame 110. By being disposed spaced apart, the reinforcement frame 120 may be disposed in a central region in a third direction (Z-axis direction) that is the height direction of the vehicle body so as to realize a maximum deformation load when an impact is applied from a second direction that is the lateral direction of the vehicle body, thereby providing an effect of improving collision energy absorption efficiency while maximizing vehicle weight reduction.

[0054] The angle between the inclined surface and the flat portion, that is, the angle formed by the extension line of the first flat portion 121 and the second flat portion 122 and the first inclined portion 123 and the second inclined portion 124, may be a value between 45° and 75°. If the angle θ formed by the extension line of the second flat portion 122 and the first inclined portion 123 and the second inclined portion 124 is less than 45°, the repeating period of the unit pattern U of the reinforcement frame 120 becomes longer, which may result in a decrease in resistance portions that resist deformation, resulting in a decrease in collision energy absorption efficiency. Similarly, if the angle θ formed by the extension line of the first flat portion 121 and the first inclined portion 123 and the second inclined portion 124 is less than 45°, a similar decrease in collision energy absorption efficiency may occur.

[0055] If the angle θ formed by the extension line of the second flat portion 122 and the first inclined portion 123 and the second inclined portion 124 exceeds 75°, the period of the repeating unit pattern U of the reinforcement frame 120 will be shortened, which will increase the amount of material used and the weight, which may have a negative impact on weight reduction. Similarly, if the angle θ formed by the extension line of the first flat portion 121 and the first inclined portion 123 and the second inclined portion 124 exceeds 75°, this may also have a negative impact on weight reduction. However, the angle is not limited to the above, and it is sufficient that a flat surface and an inclined surface are formed as described above.

[0056] According to one embodiment of the present invention, the reinforcing frame 120 may be made from a single steel plate.

[0057] The strengthening frame 120 can be formed by bending a single steel plate. By using a single steel plate, the mechanical strength of the strengthening frame 120 can be further improved, which can contribute to reducing manufacturing costs.

[0058] Furthermore, the reinforcing frame 120 may be made of a steel material having the same or greater tensile strength or yield strength than the side sill frame 110. For example, the reinforcing frame 120 may have a tensile strength of 1180 MPa or more. For example, the reinforcing frame 120 may have a yield strength of 850 MPa to 1060 MPa. Alternatively, if the side sill frame 110 and the reinforcing frame 120 are made of the same steel material, the tensile strength and yield strength may be the same.

[0059] When the reinforcing frame 120 is made of steel, it can be manufactured so that it has a tensile strength of 1180 MPa or more and a yield strength of 850 MPa to 1060 MPa. The vehicle side sill 100 including the reinforcing frame 120 thus formed has a collision energy absorption capacity that is at least equal to or potentially exceeds that of a vehicle side sill 100 made of aluminum of the same weight.

[0060] Therefore, compared to a side sill made of aluminum, the side sill 100 according to an embodiment of the present invention can achieve an equal or greater improvement in collision energy absorption efficiency while being lighter in weight.

[0061] According to one embodiment of the present invention, one side of the reinforcement frame 120 may be joined, for example, by arc welding, to the first side sill frame 111. Also, the other side of the reinforcement frame 120 may be adhered to the second side sill frame 112 with an adhesive or joined, for example, by arc welding. By being fixed by welding or adhesive in this manner, the convenience of the manufacturing process of the vehicle side sill 100 can be improved.

[0062] When a load is applied in a second direction, i.e., a lateral direction of the vehicle, the vehicle side sill 100 according to the embodiment of the present invention is compressively deformed in the second direction, thereby improving the lateral impact absorption capacity. Therefore, the impact can be minimized from being transmitted to a space where a vehicle battery (not shown) is located and a space where passengers are located.

[0063] At least one of the flat portions 121, 122 or the inclined portions 123, 124 formed on the strengthening frame 120 according to an embodiment of the present invention may include a bent portion 125 extending in the second direction. The bent portion 125 is formed to extend in the second direction. The strengthening frame 120 has the bent portion 125 extending along the second direction when viewed from the first direction.

[0064] The bent portion 125 may have a bent cross section when viewed from the second direction, and may have a straight line with a protruding or recessed cross section when viewed from the first direction.

[0065] The cross-sectional shape of the bent portion 125 as viewed from the second direction may be a shape in which an inclined first surface, a second surface symmetrical to the first surface, and a third surface existing between the first surface and the second surface and parallel to the portion of the unit pattern U in which the bent portion 125 is formed are continuously and smoothly connected.

[0066] The boundary of the third surface may not be separated, in which case the third surface may have a curved shape, and the first surface and the second surface may be connected. The shape of the curved portion 125 is not limited to the above-mentioned shapes, and includes all shapes that are protruding or recessed and formed in a straight line over a certain distance along the second direction.

[0067] The beading process can form the bent portion 125. In the beading process, a metal plate is shaped to form a bead, which is a string-like bent portion 125, on a flat or shaped metal plate.

[0068] Furthermore, the bent portion 125 may be parallel to the second direction or may be formed at a predetermined angle with the second direction, so that when viewed from the first direction, it forms a shape that is bent in a straight line along the second direction.

[0069] The formation of the bent portions 125 in the strengthening frame 120 can further increase the rigidity of the strengthening frame 120. The higher or deeper the bent portions 125, the greater the effect of increasing the rigidity.

[0070] According to an embodiment of the present invention, the bent portion 125 may be formed in at least one of the first flat portion 121, the second flat portion 122, the first inclined portion 123, and the second inclined portion 124.

[0071] The bent portion 125 is formed in the reinforced frame 120 to maximize absorption of impact in the first direction, which is a side collision, and can be formed in at least one of the first flat portion 121, the second flat portion 122, the first inclined portion 123, and the second inclined portion 124 of the reinforced frame 120.

[0072] As an example, referring to FIGS. 1 to 3, a shape in which a bent portion 125 is formed in the first inclined portion 123 and the second inclined portion 124 is shown.

[0073] However, the shape of the bent portion 125 is not limited to the above-mentioned shape, and it may be any shape as long as it is formed on the strengthening frame 120.

[0074] To list them all, the bent portion 125 may be formed in any one of the first flat portion 121, the second flat portion 122, the first inclined portion 123, and the second inclined portion 124. Alternatively, the bent portion 125 may be formed in two portions: the first flat portion 121 and the second flat portion 122, the first flat portion 121 and the first inclined portion 123, the first flat portion 121 and the second inclined portion 124, the second flat portion 122 and the first inclined portion 123, the second flat portion 122 and the second inclined portion 124, or the first inclined portion 123 and the second inclined portion 124. Furthermore, it may be formed in three parts: first flat portion 121, second flat portion 122 and first inclined portion 123; first flat portion 121, second flat portion 122 and second inclined portion 124; first flat portion 121, first inclined portion 123 and second inclined portion 124; or second flat portion 122, first inclined portion 123 and second inclined portion 124; or it may be formed in all four parts.

[0075] According to one embodiment of the present invention, the first flat portion 121, the second flat portion 122, the first inclined portion 123, and the second inclined portion 124 are formed as a unit pattern U, and the unit pattern U may be repeated in the first direction.

[0076] As an example, the unit pattern U may also include a bent portion 125 .

[0077] The first flat portion 121, the second flat portion 122, the first inclined portion 123, and the second inclined portion 124 are included in the unit pattern U, and the bent portion 125 may be formed in the above combination and repeated. When the bent portion 125 is repeatedly formed, a certain rigidity is imparted and the beading work is performed in a certain pattern, which increases the convenience of the work.

[0078] However, since the bent portion 125 is not limited to being repeatedly formed at the same position, the bent portion 125 does not have to be repeated, and the repeated unit pattern U of the reinforcement frame 120 only needs to include at least one bent portion 125, and the position at which the bent portion 125 is formed may be different each time it is repeated.

[0079] According to an embodiment of the present invention, the bent portion 125 may be formed in a central portion of the first flat portion 121, the second flat portion 122, the first inclined portion 123, or the second inclined portion .

[0080] To ensure stable beading, the bent portion 125 may be formed in the center of the surface of the part to be formed.

[0081] If there is a protruding structure inside the side sill frame 110 or if a structurally overlapping portion is formed, the bend 125 does not have to be formed in the center, but for convenient processing, it may be formed in the center. However, even if there are no special circumstances as described above, it may be formed in a portion other than the center, and is not limited to the above-mentioned position. In other words, the bend 125 may be formed as a beading structure in various positions depending on the design.

[0082] 4 and 5 show cross-sectional views of a reinforcing frame formed in accordance with yet another embodiment of the present invention.

[0083] According to one embodiment of the present invention, the bent portion 125 may be formed to protrude or recess perpendicularly from the flat surface of the first flat portion 121, the second flat portion 122, the first inclined portion 123, or the second inclined portion 124.

[0084] As described above, the surface on which the bent portion 125 is formed may be one of the first flat portion 121, the second flat portion 122, the first inclined portion 123, and the second inclined portion 124, and at least a portion of these components is formed flat. In such a surface, the bent portion 125 may be formed to protrude or recess in the vertical direction.

[0085] 4, a protruding bent portion 125 is formed on all of the first flat portion 121, the second flat portion 122, the first inclined portion 123, and the second inclined portion 124. As another example, referring to FIG. 5, a recessed bent portion 125 is formed on all of the first flat portion 121, the second flat portion 122, the first inclined portion 123, and the second inclined portion 124.

[0086] As shown in FIGS. 4 and 5, the bent portion 125 may be formed as a protrusion or a recess.

[0087] The bends 125 can be formed by beading using a beading machine. The beading machine applies an impact perpendicular to the plate surface to form a bead. The bends 125 formed by the bead can be a straight protrusion or recess in a direction perpendicular to the formed surface. When formed as a vertical protrusion or recess, the strength of the reinforcing frame 120 is increased, providing the effect of strengthening the side sill's resistance to side collisions.

[0088] Figures 6 and 7 show a reinforced frame according to still another embodiment of the present invention. Figure 6 shows a reinforced frame 120 in which bent portions 125 are formed in two places, the first flat portion 121 and the second inclined portion 124, and Figure 7 shows a reinforced frame 120 in which bent portions 125 are formed in two places, the first inclined portion 123, the second inclined portion 124, and the second flat portion 122, and the bent portions 125 are wavy.

[0089] The bent portion 125 according to an embodiment of the present invention may be formed in a wavy shape with two or more bent shapes continuously formed in a certain section.

[0090] The bent portion 125 may have a single bent shape, or may have a continuous wave-like bent shape.

[0091] When the corrugated shape is formed, the number of successive bends is not limited as long as the height or depth of the bent shape is not too low or shallow and the reinforcing effect is not lost.

[0092] The bent portions 125 provide the effect of providing additional rigidity, but it may be necessary to compromise on the height or depth and the number of the bent portions 125 depending on the thickness and shape of the reinforcement frame 120. In this case, since the height or depth of the bent portions 125 may provide more rigidity than the number of bent portions 125, the number of consecutive bent portions may be set taking this into consideration.

[0093] Furthermore, without being limited to the above embodiment, a recessed bent portion 125 and a protruding bent portion 125 may be formed together in one strengthening frame 120, and a protruding shape and a recessed shape may also be formed together within one unit pattern U. When the bent portion 125 is located in two or more portions of the first flat portion 121, the second flat portion 122, the first inclined portion 123, or the second inclined portion 124, the number of consecutive bent portions 125 formed in the corresponding portions may be different.

[0094] FIG. 8 shows a cross-sectional view of a reinforcing frame formed in accordance with yet another embodiment of the present invention.

[0095] In the unit pattern U' according to an embodiment of the present invention, the flat portion is formed only by the second flat portion 122, the inclined portions 123 and 124 include the first inclined portion 123 and the second inclined portion 124, and the bent portion 125 may be located in at least one of the second flat portion 122, the first inclined portion 123, and the second inclined portion 124. That is, the bent portion 125 may be located only in the second flat portion 122, the first inclined portion 123, or the second inclined portion 124, or may be located in two of the second flat portion 122, the first inclined portion 123, and the second inclined portion 124, or may be located in all of the second flat portion 122, the first inclined portion 123, and the second inclined portion 124. Unlike the above embodiment, the first flat portion 121 is not included, so the first inclined portion 123 and the second inclined portion 124 may be formed to abut against each other.

[0096] In this case, the number of bent portions 125 is not limited, and the same configurations and effects as those described above can be cited.

[0097] FIG. 9 shows a perspective view of a side sill including an existing reinforcing frame.

[0098] The existing side sill 10 may be configured, like the side sill of one embodiment of the present invention, such that the side sill frame 110 includes a first side sill frame 111 and a second side sill frame 112, and the reinforcing frame 120 includes a first flat portion 121, a second flat portion 122, a first inclined portion 123, and a second inclined portion 124, which are repeated to form a unit pattern U. However, the reinforcing frame 120 does not include a bent portion 125.

[0099] FIG. 10 shows a force-displacement diagram of a vehicle side sill according to an embodiment of the present invention (100 in FIG. 1) and the existing vehicle side sill of FIG. 9 (10 in FIG. 9).

[0100] In FIG. 10, the load-displacement value of the vehicle side sill (100 in FIG. 1) according to the present invention shown in FIG. 1 is indicated as a first value L1, and the load-displacement value of the vehicle side sill (10 in FIG. 9) shown in FIG. 9 is indicated as a second value L2.

[0101] Referring to the first value L1 and the second value L2, it can be seen that the vehicle side sill shown in FIG. 1 (100 in FIG. 1) has a relatively smaller displacement under the same load than the existing vehicle side sill shown in FIG. 9 (10 in FIG. 9).

[0102] Furthermore, the cross-sectional structure of the vehicle side sill (100 in FIG. 1) according to the present invention is the same as the cross-sectional structure of the existing vehicle side sill (10 in FIG. 9), except that a bent portion 125 is added to the cross-sectional structure. The same material is used, and only the bent portion 125 has been added to the shape. Considering this, it can be seen that the vehicle side sill according to one embodiment of the present invention has significantly improved impact energy absorption capabilities compared to the existing vehicle side sill.

[0103] In addition, according to the test results, the vehicle side sill (100 in FIG. 1) according to the present invention can absorb 51.2 KJ of energy when its weight is 15.9 kg, and the collision energy absorption capacity per unit weight (internal energy ratio (KJ / kg) per 1 kg) is 3.21%, while the conventional vehicle side sill (10 in FIG. 8) can absorb 48.0 KJ of energy when its weight is 15.8 kg, and the collision energy absorption capacity per unit weight (internal energy ratio (KJ / kg) per 1 kg) is 3.03%. Therefore, it can be confirmed that the vehicle side sill according to the present invention has better collision energy absorption capacity when it has a similar weight to the conventional vehicle side sill.

[0104] According to the present invention, the vehicle side sill can be made lighter than the existing aluminum structure, while its collision energy absorption capacity can be improved compared to when the existing bent portion 125 is not formed.

[0105] Furthermore, by arranging the reinforcing frames 120 at optimal positions inside the side sill frame 110, it is possible to achieve maximum impact energy absorption capacity with a minimum number of reinforcing frames 120 and a minimum weight of the reinforcing frames 120.

[0106] The matters described above are described with respect to one embodiment of the present invention, and the scope of the present invention is not limited thereto. It is obvious to a person having ordinary knowledge in the art that various modifications and variations are possible within the scope that does not deviate from the technical idea of ​​the present invention described in the claims. [Explanation of symbols]

[0107] 10: Existing side sill 100: Side sill 110: Side sill frame 111: First side sill frame 112: Second side sill frame 113: Hollow part 114:Joining part 120: Reinforced Frame 121: 1st plane part 122:Second plane part 123:First slope part 124:Second slope part 125: Bend U, U': unit pattern

Claims

1. a side sill frame extending in a first direction and including a hollow portion; a reinforcing frame disposed in the hollow portion and including a plurality of unit patterns extending in the first direction; Including, The unit pattern is a planar portion disposed on a plane formed by the first direction and a second direction intersecting the first direction; an inclined portion disposed adjacent to the flat portion and inclined relative to the flat portion; Including, At least one of the flat portion and the inclined portion includes a bent portion extending in the second direction.

2. The planar portion is a first planar portion disposed in the first direction; a second flat portion disposed in the first direction and positioned lower than the first flat portion; Including, The inclined portion is a first inclined portion disposed obliquely following the first flat portion; a second inclined portion disposed obliquely following the second flat portion; The vehicle side sill of claim 1 , comprising:

3. The bent portion is The vehicle side sill according to claim 2 , wherein the first flat portion, the first inclined portion, the second flat portion, or the second inclined portion is positioned at a central portion of the first flat portion, the first inclined portion, the second flat portion, or the second inclined portion.

4. The vehicle side sill according to claim 2 , wherein the bent portion has two or more successive bent shapes and is wavy.

5. The bent portion is The vehicle side sill according to claim 2 , wherein the first flat surface, the second flat surface, the first inclined surface, or the second inclined surface is formed to protrude or recess in a direction perpendicular to the flat surface.

6. The vehicle side sill according to claim 2 , wherein the first and second planar portions and the side sill frame are spaced apart from each other.

7. 2. The vehicle side sill according to claim 1, wherein the reinforcing frame is made of a single steel plate.

8. 7. The vehicle side sill according to claim 2, wherein the first planar portion, the second planar portion, the first inclined portion, and the second inclined portion are formed in a unit pattern, and the unit pattern is repeated in the first direction.

9. 7. The vehicle side sill according to claim 2, wherein the first planar portion and the second planar portion have a length in the first direction of the side sill frame of 40 mm to 70 mm.

10. 7. The vehicle side sill according to claim 2, wherein an angle formed by an extension line of the first flat portion or the second flat portion and the first inclined portion or the second inclined portion is a value of 45° to 75°.

11. 2. The vehicle side sill according to claim 1, wherein the thickness of the reinforcing frame is between 1.8 mm and 2.2 mm.

12. The reinforcing frame is The steel material has the same or higher tensile strength or yield strength than the side sill frame, 2. The vehicle side sill according to claim 1, wherein the reinforcing frame has a tensile strength of 1180 MPa or more and a yield strength of 850 MPa to 1060 MPa.

Images