JP7253102B1 - Shock absorbing member, method for manufacturing shock absorbing member for automobile, and method for manufacturing side sill - Google Patents

Abstract

An object of the present invention is to manufacture an inexpensive shock absorbing member made of a steel plate with high productivity. A closed cross-section half forming step S1 is provided for forming a closed cross-section half by press-molding a steel plate blank into a hat-shaped cross section having a cap and a pair of flanges. At least two closed cross-section halves are combined so that the convex directions of the cap portions are opposite to each other, and the top of the cap portion of one half of the closed cross-section and the brim of the other half of the closed cross-section are combined. and a closed cross-section structure forming step S2 of overlapping and joining to form a closed cross-section structure. [Selection drawing] Fig. 7

Description

TECHNICAL FIELD The present invention relates to a shock absorbing member for absorbing a shock applied to the body of an automobile from the side, a method for manufacturing the shock absorbing member for a car, and a method for manufacturing a side sill.

2. Description of the Related Art Conventionally, as a reinforcing member that reinforces a side portion of a vehicle body of an automobile, there is one described in Patent Document 1, for example. The reinforcing member disclosed in this publication is provided inside a side sill of a vehicle body, and has a plurality of hollow portions having a closed cross-sectional shape when viewed from the front-rear direction of the vehicle body. The plurality of hollow portions are formed by extrusion using an aluminum alloy as a material, and extend in the front-rear direction of the vehicle body while being aligned in a row in the vehicle width direction. The reinforcing member absorbs the impact applied to the side portion of the vehicle body toward the inside of the vehicle body by collapsing the hollow portion.

Japanese Patent Application Laid-Open No. 2018-90021

In the reinforcing member described in Patent Document 1, there is a problem that the manufacturing cost is high because the aluminum alloy is more expensive than the steel plate and the equipment for extrusion molding is expensive.

SUMMARY OF THE INVENTION An object of the present invention is to manufacture an inexpensive shock absorbing member made of steel plate with high productivity.

In order to achieve this object, a method for manufacturing a shock absorbing member for an automobile according to the present invention comprises press-molding a steel blank into a hat-shaped cross-section having a hat portion and a pair of brim portions to form a closed cross-section half portion. a step of forming the closed cross-section half portion, and combining at least two of the closed cross-section half portions so that the convex directions of the cap portions are opposite to each other; a step of forming a closed cross-section structure by overlapping and joining the top portion and the flange portion of the other half of the closed cross-section structure to form a closed cross-section structure.

Further, in the present invention, a closed cross-section half portion is added to the closed cross-section structure body, and the adjacent cap portions are combined so that the convex directions of the cap portions are opposite to each other, and the cap of one of the closed cross-section half portions is The top portion of the section and the flange portion of the other closed section construction half section may be overlapped and joined to form a second closed section construction body to have a hollow structure that is substantially V-shaped when viewed from the cross-sectional direction. good.

Further, in the present invention, the closed cross-section half portion may be formed continuously in common with a plurality of cap portions and brim portions.

Further, according to the present invention, the closed cross-section body is formed by varying the vertical and horizontal dimensions, plate thickness, material, etc., of one or both of the cap portion or brim of the closed cross-section half. may

In the present invention, a plurality of cap portions are arranged in the longitudinal direction of the impact absorbing member, and the upper and/or lower impact absorbing portions that are continuous at the brim portion are used as the first intermediate part. and combining the upper and lower impact absorbing portions so that the convex directions of the cap portion are opposite to each other, and the top portion of the cap portion of one of the closed cross-section half portions and the other and a shock absorbing member forming step of overlapping and joining the flange portion of the closed cross section forming half of the above to form a closed cross section forming body and joining them to each other to form an elongated shock absorbing member. good too.

Further, according to the present invention, a plurality of the closed cross-section halves are combined so that the convex directions of the cap portions are opposite to each other, and the top of the cap portion of one of the closed cross-section halves is the other. a second intermediate component forming step of forming at least two or more second intermediate components by overlapping and joining the flange portion of the closed cross-section half; a shock absorbing member forming step of overlapping and joining the top portion of the cap portion of the second intermediate component and the brim portion of the other second intermediate component to form a long shock absorbing member; may

Further, in the closed section structure forming step, the closed section structure halves constituting the shock absorbing member are separated from each other in a state in which the closed section structure halves are not joined to each other, and the adjacent cap portion has a convex shape. Combined as a posture in which the directions of becoming are opposite to each other,
The top portion of the cap portion of the closed cross-section half portion may be overlapped and joined to the brim portion of the adjacent closed cross-section half portion in the opposite posture.

Further, in the present invention, at least one or both of the brim portions are formed with at least one or more grooves adjacent to or not adjacent to the cap portion, and corner ridges extending in the left-right direction are formed along the hollow structure to form a closed cross-section. may be added to the construct.

In addition, the present invention may add any one or more of a step shape, a smaller groove, two or more small second grooves, and a raised portion to the groove.

Moreover, the present invention may have a fixing member that protrudes outward from the closed cross-section of the shock absorbing member.

In addition, the present invention further comprises the steps of: joining a shock absorbing member formed by the method for manufacturing a shock absorbing member to an outer side sill; and joining the outer side sill to which the shock absorbing member is joined and the inner side sill. may have.

In addition, the present invention further comprises the steps of: joining a shock absorbing member formed by the method for manufacturing a shock absorbing member to an inner side sill; and joining the inner side sill and the outer side sill to which the shock absorbing member is joined. may have.

In the shock absorbing member according to the present invention, a plurality of closed cross-section halves each having a hat-shaped cross section and having a cap portion and a pair of brim portions are prepared, and at least two of the closed cross-section halves are arranged in a convex direction of the cap portion. are opposite to each other, and the top portion of the cap portion of one of the closed cross-section half portions and the flange portion of the other closed cross-section half portion are overlapped and joined, and have a hollow body and a connecting piece. A closed cross-section body is formed, and the closed cross-section body has a connecting piece aligned with the upper surface or the lower surface of the hollow body, and the upper surface and the connecting piece, and the lower surface and the connecting piece are vertically offset along the side sill inner. It is arranged in the longitudinal direction.

According to the present invention, at least two sets of steel plates each having a half portion (cap portion) of a hollow body and a connecting piece (flange portion) formed by bending press working are produced, and these steel plates are combined to form a shock absorbing member. can be formed.
Therefore, the impact absorbing member can be manufactured by subjecting a steel plate, which is cheaper than aluminum alloy, to simple bending press working and welding (or rivets or other connecting means). Therefore, it is possible to provide an inexpensive shock absorbing member made of steel plate.

In particular, if there is a single mold for press-molding one cap portion and a brim portion, a plurality of cap portions can be connected in the longitudinal direction like stepping stones via the brim portion, thereby manufacturing a shock absorbing member of any length at a low cost. can get to By simply adding grooves to the collar, the ridges of the hollow structure can be increased to increase impact energy absorption. This is because this hollow structure absorbs the impact energy by sequentially buckling the ridge from the tip to the base end due to a load from the side.

Further, according to the present invention, the impact absorbing member can be assembled to the outer side sill by the fixing member, and the outer side sill can be assembled to the inner side sill in a state in which they are integrated. Automobile side sills can be manufactured with high productivity.

FIG. 1 is a perspective view of part of an automobile body frame showing an exploded side sill. FIG. 2 is a cross-sectional view of the side sill. 3A and 3B are a perspective view of the impact absorbing member and a front view of the vehicle body. FIG. 4 is a perspective view of a closed cross-section half and a cross-sectional view of a closed cross-section structure. FIG. 5 is a perspective view of a closed section half with a sill outer securing member. FIG. 6 is a front view of a portion of the shock absorbing member showing an example of formation of the sill outer fixing member. FIG. 7 is a flow chart for explaining an example of a method for manufacturing a shock absorbing member. FIG. 8 is a front view for explaining an example of the method of manufacturing the impact absorbing member. FIG. 9 is a flow chart for explaining an example of a method for manufacturing a shock absorbing member. FIG. 10 is a perspective view for explaining an example of the method of manufacturing the impact absorbing member. FIG. 11 is a flow chart for explaining an example of a method for manufacturing a shock absorbing member. FIG. 12 is a perspective view for explaining an example of the method of manufacturing the impact absorbing member. FIG. 13 is a flow chart for explaining an example of a method for manufacturing a shock absorbing member. FIG. 14 is a front view for explaining an example of the method of manufacturing the impact absorbing member. FIG. 15 is a flow chart for explaining an example of a side sill manufacturing method. FIG. 16 is a cross-sectional view for explaining an example of the side sill manufacturing method. FIG. 17 is a flow chart for explaining a modification of the side sill manufacturing method. FIG. 18 is a schematic diagram for explaining the configuration of the shock absorbing member. FIG. 19 is a schematic diagram for explaining the configuration of the side sill. FIG. 20 is a cross-sectional view for explaining the shock absorbing principle of the shock absorbing member. FIG. 21 is a cross-sectional view for explaining the shock absorbing principle of the shock absorbing member. FIG. 22 is a perspective view of another embodiment of a closed section half. FIG. 23 is a perspective view showing another embodiment of the shock absorbing member. FIG. 24 is a cross-sectional view showing a modification of a closed cross-section having corners.

(First embodiment)
1 to 21, an impact absorbing member, a method for manufacturing an impact absorbing member, and a method for manufacturing a side sill according to an embodiment of the present invention will be described in detail below.
An automobile body frame 1 shown in FIG. 1 can be used for an electric vehicle (not shown), and includes a front pillar inner 2, a center pillar inner 3, and side sills 4 at both ends in the vehicle width direction. (Front pillar outer and center pillar outer are not shown). FIG. 1 shows the side sill 4 in an exploded state.

(Description of side sills)
The side sill 4 according to this embodiment is formed in a tubular shape extending in the longitudinal direction of the vehicle by combining two parts. Inside the side sill 4 is housed a shock absorbing member 6 that cooperates with the side sill 4 to constitute the side sill structure 5 of the present invention. A detailed description of the shock absorbing member 6 will be given later.
The two parts constituting the side sill 4 are a side sill inner 7 extending in the longitudinal direction of the vehicle inside the vehicle body and an outer side sill 8 extending in the longitudinal direction of the vehicle outside the vehicle body. As shown in FIG. 2, the inner side sill 7 and the outer side sill 8 are composed of main bodies 7a and 8a each having a U-shaped cross section and upper flanges 7b for welding integrally formed at the ends of the main bodies 7a and 8a. , 8b and lower flanges 7c, 8c.

The side sill inner 7 is welded to the floor panel (not shown) of the vehicle body frame 1 and the cross member 11 with the open portion of the U-shaped main body 7a directed to the outside of the vehicle body.
The side sill outer 8 is welded to the side sill inner 7 with the open portion of the U-shaped main body 8a directed toward the inside of the vehicle body.
The upper flanges 7b, 8b of the side sill inner 7 and the side sill outer 8 protrude upward from the upper ends of the main bodies 7a, 8a in the vehicle-mounted state. The lower flanges 7c, 8c protrude downward from the lower ends of the main bodies 7a, 8a in the vehicle-mounted state. These upper flanges 7b, 8b and lower flanges 7c, 8c extend from the front end to the rear end of the side sill inner 7 and the side sill outer 8, respectively. The welding of the side sill inner 7 and the side sill outer 8 is performed by overlapping the upper flanges 7b, 8b of the side sill outer 7 and the side sill outer 8 with each other and spot-welding them, and also overlapping the lower flanges 7c, 8c with each other. It is done by applying spot welding to

The impact absorbing member 6 is for absorbing the impact applied to the side sill 4 from the side of the vehicle body. Cost can be reduced by setting the length and location according to the side impact test.
A holding member 12 for supporting the shock absorbing member 6 in the side sill 4 is welded to the lower end of the shock absorbing member 6 . The inner joint piece 13 is welded. Although not shown, the center pillar inner 3 has a center pillar outer and forms a closed cross section extending vertically.
A holding member 12 extending downward from the impact absorbing member 6 is fixed to the lower flanges 7c, 8c by spot welding while being sandwiched between the lower flanges 7c, 8c. A center pillar inner connecting piece 13 extending upward from the impact absorbing member 6 is sandwiched between the upper flanges 7b and 8b and fixed to the upper flanges 7b and 8b by spot welding to form an impact absorbing member. The lower part of the center pillar inner 3 is securely fixed via 6.

(Description of shock absorbing member)
As shown in FIGS. 3(A) and 3(B), the shock absorbing members 6 are spaced apart by a predetermined distance in the longitudinal direction of the vehicle body {in FIGS. It has a plurality of hollow bodies 14 arranged side by side and a plurality of connecting pieces 15 connecting these hollow bodies 14 to each other. 3A is a perspective view of the shock absorbing member 6, and FIG. 3B is a front view of a portion of the shock absorbing member 6 as seen from the side of the vehicle body.

The hollow body 14 has a shape such that a closed cross section 16 is formed when viewed from the side of the vehicle body of the automobile, and is formed in a tubular shape extending in the vehicle width direction. The hollow body 14 according to this embodiment is formed in the shape of a square tube whose closed cross section 16 is a parallelogram. Here, in order to specify the plurality of hollow bodies 14, for convenience, in FIG. They are referred to as body 14C, fourth hollow body 14D, fifth hollow body 14E, and sixth hollow body 14F.

The connection piece 15 is formed in a plate-like shape extending in the front-rear direction and the vehicle width direction of the vehicle body, and is located at a position where two hollow bodies 14 adjacent to each other are vertically offset from each other with respect to the hollow body 14, that is, at a position that is biased in the vertical direction. connected with As shown in FIGS. 3A and 3B, when three or more hollow bodies 14 are provided and have a plurality of connection pieces 15 in the longitudinal direction of the vehicle body, the positions of the connection pieces 15 in the vertical direction are Distributed alternately in direction. That is, the connecting piece 15 connecting the first hollow body 14A and the second hollow body 14B connects the upper ends of the first and second hollow bodies 14A and 14B, but the second hollow body 14A and the second hollow body 14B are connected to each other. A connection piece 15 connecting the hollow body 14B and the third hollow body 14C connects the lower ends of the second and third hollow bodies 14B and 14C.

The hollow body 14 and the connecting piece 15 described above are closed by combining the first and second closed cross-section halves 17 and 18 shown in FIGS. 4(A) and (B) with each other as shown in FIG. It is formed by forming a cross-sectional structure 19 . 4(A) is a perspective view showing the first closed cross-section construction half 17, FIG. 4(B) is a perspective view showing the second closed cross-section construction half 18, and FIG. 4(C) is a closed cross-section construction. FIG. 4 is a cross-sectional view of body 19;
The first closed-section half portion 17 and the second closed-section half portion 18 are formed by pressing a steel plate to have a hat cross-sectional shape, and each have two functional portions.

The first functional portion is hat portions 17a and 18a formed in a substantially U-shape and positioned at the center of the vehicle body in the front-rear direction (left-right direction in FIGS. 4A and 4B). The cap portions 17a and 18a have a flat top portion 21 and a pair of inclined walls 22 connected to the front and rear end portions of the adjustment portion and extending in the vertical direction. The top portion 21 is formed flat so as to extend in the horizontal direction. The pair of inclined walls 22 constitute the side portions of the cap portions 17a and 18a, and are inclined in such a direction that the interval between the inclined walls 22 gradually widens as the distance from the top portion 21 increases, thereby facilitating press molding. The tip portion of the slanted wall 22 constitutes a collar portion that is bent and parallel to the top portion 21 in order to connect to a second functional portion which will be described later. The inclined wall 22 of the first closed section half 17 shown in FIG. 4A extends upward from the top 21 . A sloped wall 22 of the second closed section half 18 shown in FIG. 4B extends downwardly from the top 21 .

A (sill outer) fixing member 23 can be provided on the inclined wall 22 as shown in FIGS. The (sill outer) fixing member 23 is for connecting the shock absorbing member 6 to the side sill outer 8 or the side sill inner, and is formed in a plate shape and extends from one inclined wall 22 toward the other inclined wall 22 (closed). (towards the outside of cross-section 16).
There are two methods of providing the (sill outer) fixing member 23 on the inclined wall 22 . A first method is a method of forming integrally with the inclined wall 22 as shown in FIG. 5(A). The second method is a method of forming a separate member from the inclined wall 22 and welding it to the inclined wall 22 as shown in FIG. 5(B).

The second functional portion is a pair of brim portions 17b, 18b (see FIGS. 4A and 4B) projecting from both ends of the cap portions 17a, 18a in the longitudinal direction of the shock absorbing member 6. The brim portion 17b. , 18b constitute the upper and lower ends of the hollow body and the connection piece 15, and are formed in the shape of a flat plate extending in the horizontal direction, and protrude from the tip (lower end or upper end) of the inclined wall 22 in the longitudinal direction of the vehicle body.
The first closed cross-section half 17 and the second closed cross-section half 18 may have the same shape or different shapes. For example, depending on the required shock absorbing form, the number of cap portions on one side may be increased, the length, thickness and strength of the top portion 21 and inclined wall 22 may be increased or decreased, or the shape may be changed. You can change it. Of course, if the first closed-section half portion 17 and the second closed-section half portion 18 have the same shape, only one mold is required for press molding, which reduces the facility cost.

The first half portion 17 and the second half portion 18 are, as shown in FIG. 4C, the first half portion 17 and the second half portion 18. The convex direction of 18 is opposite to the vertical direction, and the tops 21 of the first closed cross-section half 17 and the second closed cross-section half 18 overlap with the tip of one of the flanges 17b and 18b. connected to each other. In FIG. 4C, the top portion 21 of the first closed cross-section half portion 17 and the tip of the flange portion 18b of the second closed cross-section half portion 18 on the front side of the vehicle body overlap, and the first closed cross-section half portion The tip of the flange portion 17b of the portion 17 on the rear side of the vehicle body overlaps with the top portion 21 of the second half portion 18 having a closed cross section.

The first closed cross-section half portion 17 and the second closed cross-section half portion 18 are joined together by spot welding the above-described two overlapped portions. By connecting the first closed-section half 17 and the second closed-section half 18 in this way, the closed-section body 19 is formed, and the first and second closed-section half A closed cross section 16 (hollow body) is formed by inclined walls 22, 22 of cap portions 17a, 18a facing each other and brim portions 17b, 18b facing each other.

(Description of the manufacturing method of the shock absorbing member)
There are four methods for manufacturing the impact absorbing member 6 extending in the front-rear direction of the vehicle body using the first closed-section half portion 17 and the second closed-section half portion 18 as follows.
The first manufacturing method is carried out as shown in the flow chart of FIG. First, as shown in step S1 of the flow chart of FIG. 7, the first closed cross-section half 17 and the second closed cross-section half 18 are press-molded {see FIG. 8A}. When the sill outer fixing member 23 is formed integrally with the first and second closed cross-section construction half portions 17 and 18, the sill outer fixing member 23 is bent in the longitudinal direction of the shock absorbing member 6 in this step. .
When the sill outer fixing member 23 is welded to the first closed cross-section half 17 and the second closed cross-section half 18, this step is performed.

Next, as shown in FIG. 8B, the first closed cross-section half 17 and the second closed cross-section half 18 are combined and welded to form the closed cross-section body 19 (step S2). ). The number of closed cross-section bodies (hollow bodies) 19 corresponding to the length of the impact absorbing member 6 is formed. For example, as shown in FIG. 8(D), a blank is press-molded such that two cap portions 17a and 18a are arranged in the first half portion 17 and the second half portion 18 forming a closed cross section. good too. Then, as shown in FIG. 8(C), a plurality of closed cross-section structures 19 are arranged in a line in the longitudinal direction of the vehicle body, and adjacent closed cross-section structures 19 are welded to each other. At this time, the top portions 21 of the hat portions 17a and 18a and the flange portions 17b and 18b are overlapped, and the overlapping portions are welded by spot welding (step S3). The elongated impact absorbing member 6 is completed by joining a plurality of closed cross-section structures 19 in this way.

The second manufacturing method is carried out as shown in the flow chart of FIG. First, as shown in step S11 of the flow chart of FIG. 9, the first closed cross-section half 17 and the second closed cross-section half 18 are formed. The first closed-section half 17 and the second closed-section half 18 are formed as shown in FIG. 8(A). Next, as shown in the first intermediate component formation step S12 of the flow chart and FIG. 10, the upper first intermediate component 31 and the lower first intermediate component 32 are formed. In this case, a plurality of first closed cross-section halves 17 are arranged in the longitudinal direction of the vehicle body, and adjacent first closed cross-section halves 17 are welded together to form an upper first intermediate part as an intermediate part. 31 is formed. Also, a plurality of second closed cross-section halves 18 are arranged in the longitudinal direction of the vehicle body, and adjacent second closed cross-section halves 18 are welded together to form a lower first intermediate part 32 as an intermediate part. to form The first intermediate parts 31 and 32 do not have a closed cross-section.

After that, the upper first intermediate part 31 and the lower first intermediate part 32 are assembled so that the convex directions of the cap portion are opposite to each other, and the cap portion of one of the closed cross-section half portions is combined. The top portion and the flange portion of the other half portion having the closed cross section are overlapped and joined together (shock absorbing member forming step S13). At this time, the top portion 21 of the hat portion 17a of the first intermediate component 31 of the upper divided body is welded to the flange portion 18b of the first intermediate component 32 of the lower side by spot welding, and the first intermediate component of the upper side is welded. The flange portion 17b of the component 31 is welded to the top portion 21 of the cap portion 18a of the lower first intermediate component 32 by spot welding. By joining the upper first intermediate component 31 and the lower first intermediate component 32, which are intermediate components, to each other, the elongated impact absorbing member 6 is completed.

The third manufacturing method is carried out as shown in the flow chart of FIG. First, as shown in step S21 of the flow chart of FIG. 11, the first closed cross-section half 17 and the second closed cross-section half 18 are formed. The first closed-section half 17 and the second closed-section half 18 are formed as shown in FIG. 8(A). Next, as shown in FIG. 12, the first half section 17 and the second half section 18 are combined so that the convex directions of the cap portions are opposite to each other. The top of the cap portion of the closed cross-section half is overlapped and joined to the flange of the other closed cross-section half to form at least two or more second intermediate parts 33 (second intermediate parts). Part formation step S22). The second intermediate part 33 has a closed cross-section. FIG. 12 shows a second intermediate part 33A and a second intermediate part 33B. After that, the second intermediate component 33A and the second intermediate component 33B are arranged in the front-rear direction and welded to each other (impact absorbing member formation step S23). By joining the second intermediate component 33A and the second intermediate component 33B, which are intermediate components, in this manner, the elongated impact absorbing member 6 is completed.

The fourth manufacturing method is carried out as shown in the flow chart of FIG. First, as shown in step S31 of the flow chart of FIG. 13, the first closed cross-section half 17 and the second closed cross-section half 18 are formed. The first closed-section half 17 and the second closed-section half 18 are formed as shown in FIG. 8(A). Next, as shown in step S32 of the flow chart and FIG. 14, the impact absorbing member 6 is formed. At this time, the closed cross-section halves constituting the impact absorbing member 6 are combined in a state in which the closed cross-section halves are not joined to each other, and the adjacent cap portions project in opposite directions, The elongated impact absorbing member 6 is completed by overlapping and joining the top of the cap portion of the closed cross-section half to the brim of the adjacent closed cross-section half in a position opposite to the closed cross-section half. do. The apex of the cap part of the closed cross-section half part may be overlapped and joined to the brim part of the adjacent closed cross-section half part on both sides in the opposite posture to the closed cross-section half part.

(Description of side sill manufacturing method)
In order to manufacture the side sill 4 having the impact absorbing member 6 formed in an elongated shape, the steps shown in the flow chart of FIG. 15 are carried out. First, as shown in FIG. 16A, the holding member 12 and the center pillar inner connecting piece 13 are joined to the impact absorbing member 6 (step S41). When the (sill outer) fixing member 23 is welded to the first and second closed cross section forming half portions 17 and 18 of the impact absorbing member 6, this process is carried out.

Next, as shown in FIG. 16B, the side sill outer 8 is joined to the shock absorbing member 6 (step S42). This joining is performed by welding the side sill outer 8 to the (sill outer) fixing member 23 . Then, as shown in FIG. 16C, the side sill outer 8 and the side sill inner 7 to which the impact absorbing member 6 is joined are joined (step S43). This joining is performed by overlapping the upper flange 7b and the lower flange 7c of the side sill inner 7 and the upper flange 8b and the lower flange 8c of the side sill outer 8 and spot welding them. When performing this joining, the holding member 12 and the center pillar inner connecting piece 13 are sandwiched between the flanges, and these members are also joined to the flanges at the same time. The side sill 4 is completed by joining the side sill outer 8 to the side sill inner 7 . At this time, the center pillar inner connecting piece 13 is also joined to the lower end of the side sill inner 7 .

(Description of another method of manufacturing side sills)
In order to manufacture the side sill 4 having the shock absorbing member 6 formed in an elongated shape, it can be carried out as shown in the flow chart of FIG. In the manufacturing method of the side sill 4, first, in step S51, the shock absorbing member 6 is joined to the side sill inner 7. As shown in FIG. In this case, an inner sill fixing member (not shown) equivalent to the outer sill fixing member 23 is provided in advance on the impact absorbing member 6, and the inner sill fixing member is welded to the inner side sill 7 in step S51. Next, the side sill outer 8 is welded to the side sill inner 7 in step S52. In this step S52, the holding member 12 and the center pillar inner connecting piece 13 are sandwiched between the upper and lower flanges 7b and 7c of the side sill inner 7 and the upper and lower flanges 8b and 8c of the side sill outer 8, respectively. are spot welded at the same time. The side sill 4 is completed by joining the side sill outer 8 to the side sill inner 7 .
By adopting this manufacturing method and joining the shock absorbing member 6 to the side sill inner 7 side, it is possible to easily perform positional alignment so that the load can be transmitted to the rigid member (cross member) on the floor side.

(Description of effects of this embodiment)
As shown in FIG. 18, the impact absorbing member 6 according to this embodiment includes at least two or more hollow bodies 14 arranged at a predetermined interval in the longitudinal direction of the vehicle body with a closed cross section 16 extending in the vehicle width direction. and a connection piece 15 (collars 17b, 18b, top 21) that connects the hollow bodies 14 adjacent to each other at positions offset in the vertical direction with respect to the hollow bodies 14 (positions offset in the vertical direction). . When a plurality of connection pieces 15 are provided in the longitudinal direction of the vehicle body, the vertical positions of the connection pieces 15 are alternately distributed in the longitudinal direction of the vehicle body. The impact absorbing member 6 has a configuration in which the connection piece 15 (flanges 17b and 18b) is vertically offset from the centroid A of the hollow body 14 when viewed from the side, and is largely separated from the centroid A. ing. Therefore, compared with the case where the connection piece 15 is positioned at the same height as the centroid A of the hollow body 14, the geometrical moment of inertia increases.

Furthermore, since the pair of hollow bodies 14, 14 are formed in the shape of an inverted V, the strength of the connection piece 15 can be further increased, and the collision load to the biased position of the connection piece 15 can be firmly received, and the shock absorbing member 6 can be pushed outward.・Can be crushed from the tip. Since the V-shapes are alternately overlapped in the front-rear direction, it is possible to absorb not only the side impact load but also any inclined input such as upward, downward, forward, and rearward.

Further, since the connecting piece 15 is offset in the vertical direction with respect to the centroid A of the hollow body 14, the connecting piece 15 is located at the upper corner portion 41 and the lower corner portion 42 of the side sill inner 7 as shown in FIG. become closer to Since the upper corner portion 41 and the lower corner portion 42 of the side sill inner 7 are corner portions, the rigidity in the vehicle width direction is higher than that of the flat portion compared to other portions.
Therefore, compared to the case where the connection piece 15 is not vertically offset, the vertical surface of the side sill inner 7 is less likely to bend in the event of a collision in which an impact load is applied to the side sill 4 from the side of the vehicle body, that is, in a side collision. As indicated by a two-dot chain line, the deformation 43 progresses from the outer end of the vehicle body to the inner side of the vehicle body, and the impact absorbing member 6 is crushed. As a result, the amount of impact energy absorbed increases.

In addition, since the connection pieces 15 are offset in the vertical direction with respect to the centroid A of the hollow body 14 , the upper and lower surfaces of the hollow body 14 and the upper and lower connection pieces 15 are aligned with the upper and lower corners of the side sill inner 7 . get closer. Since the upper and lower corners of the side sill inner 7 have high rigidity and strength, and the side impact load is dispersed vertically, the side sill inner 7 is held against the side impact load, and the movement of the shock absorbing member 6 to the interior of the room is suppressed. It advances from the end on the outside of the vehicle to the inside of the vehicle in order to crush the impact absorbing member 6 and help increase the amount of impact energy absorbed {see FIG. Furthermore, although not shown, the movement of the impact absorbing member 6 to the interior side of the room is further suppressed because the lower floor and the upper cross member are also approached.
On the other hand, as shown in FIG. 21(B), when the connection piece 15 is not vertically offset and is located in the center, the side sill inner 7 deforms out of plane in the event of a side collision, and the shock absorbing member 6 moves out of the chamber. Otherwise, the impact absorbing member 6 is tilted inside the side sill 4, its posture is not stable, and it cannot be crushed sequentially from the end on the outside of the vehicle body toward the inside of the vehicle body.

The hollow body 14 and the connection piece 15 of the impact absorbing member 6 according to this embodiment are formed by combining a pair of closed cross-section half portions (first closed cross-section half portion 17 and second closed cross-section half portion 18). formed. The closed cross-section half portion includes hat portions 17a and 18a formed in a U-shape and a pair of brim portions protruding in the longitudinal direction of the impact absorbing member 6 from both ends of the hat portions 17a and 18a. 17b and 18b. The pair of closed cross-section halves are coupled to each other in a state in which the cap portions 17a and 18a protrude in opposite directions in the vertical direction and the top portions 21 of the cap portions 17a and 18a overlap with one of the collar portions 17b and 18b. It is A closed cross section 16 is formed by the side portions (inclined walls 22) of the cap portions 17a and 18a facing each other and the flange portions 17b and 18b facing each other of the pair of closed cross section forming halves.

Therefore, since the members that are the minimum units to be press-formed in manufacturing the shock absorbing member 6 are the half portions 17 and 18 having the cap portions 17a and 18a, the steel plate can be easily press-formed. Become. The reason for this is that the inclined wall 22 does not cause an undercut during press molding. In addition, this press molding may be configured using a component having a shape in which two or more cap portions, for example, two closed cross-section half portions 17 are arranged in the longitudinal direction of the vehicle body as a minimum unit. In this embodiment, as shown in FIG. 3(B), a plurality of closed cross-section halves are combined so that the flanges 17b, 18b (connecting pieces 15) are divided vertically in the longitudinal direction of the vehicle body. Therefore, the number of steel plates in the spot-welded portion is three between the top portion 21 and the flange portions 17b and 18b. Therefore, the reliability of spot welding is enhanced.

The automobile side sill structure 5 according to this embodiment includes a sill outer fixing member 23 projecting outward from the closed cross section 16 of the shock absorbing member 6 as shown in FIG. A side sill outer 8 joined to the sill outer fixing member 23 in a state surrounding the side sill outer 6 from the outside of the vehicle body. When the sill outer fixing members 23 extend toward the inside of the closed cross section 16 as shown in FIG. 6B, adjacent sill outer fixing members 23 interfere with each other. Therefore, in this case, in order to avoid interference between the sill outer fixing members 23, the closed cross section 16 must be expanded in the longitudinal direction of the vehicle body to such a size that the sill outer fixing members 23 do not interfere with each other. As a result, the number of closed cross-sections 16 in the shock absorbing member 6 as a whole is reduced, and the amount of energy absorbed by the shock absorbing member 6 at the time of a side collision is reduced. However, since the sill outer fixing member 23 according to this embodiment extends toward the outside of the closed section 16 as shown in FIG. Therefore, interference between the sill outer fixing members 23 can be prevented.

As shown in FIG. 2, the side sill structure 5 for an automobile according to this embodiment includes a side sill inner 7 surrounding the shock absorbing member 6 from the inside of the vehicle body, a side sill outer 8 surrounding the shock absorbing member 6 from the outside of the vehicle body, and the shock absorbing member 6. and a holding member 12 that supports from below. Therefore, the impact absorbing member 6 can be held in a stable state within the side sill 4, so that the impact absorbing member 6 does not tilt or fall when the side sill 4 receives an impact from the side of the vehicle body, thereby absorbing the impact. The upper and lower surfaces of the member 6 are deformed so as to buckle and absorb the impact.
Moreover, since the impact absorbing member 6 can be held without being joined to the side sill inner 7, manufacturing is facilitated.
Therefore, the side sill structure 5 that is strong against side collisions can be easily realized.

In the automobile side sill structure 5 according to this embodiment, the center pillar inner 3 is joined to the upper surface of the shock absorbing member 6 as shown in FIG. Therefore, the collision energy can be transmitted from the impact absorbing member 6 to the center pillar inner 3, so that the side sill structure 5 that is even stronger against side collisions can be obtained.

The impact absorbing member 6 according to this embodiment can be joined to the side sill inner 7, although not shown. That is, by firmly joining the impact absorbing member 6 to the side sill inner 7 with an adhesive or the like, it is possible to realize the side sill structure 5 with further improved strength.

As a method of manufacturing the shock absorbing member 6, as shown in FIGS. 7 and 8, a step of forming a plurality of closed cross-section half portions (first closed cross-section half portion 17 and second closed cross-section half portion 18). By adopting a method including S1, step S2 of forming closed cross-section bodies 19, and step S3 of combining a plurality of closed cross-section bodies 19 to form an elongated impact absorbing member 6, a plurality of Since the impact-absorbing member 6 can be manufactured by combining closed cross-section half portions, which are the minimum components, impact-absorbing members 6 of various shapes and lengths can be manufactured. . In addition, when a defective product occurs, each half of the closed cross section structure can be replaced, so the yield is increased when a defective product occurs. Furthermore, since a press die for forming the steel sheet into a predetermined shape may be small, it is possible to reduce the manufacturing cost of equipment required for manufacturing.

As shown in FIGS. 9 to 12, as a method of manufacturing the shock absorbing member 6, steps S11 and S21 of forming closed cross-section halves, and joining a plurality of closed cross-section halves to each other to form an intermediate part (first A first intermediate part forming step S12 and a second intermediate part forming step S22 for forming an intermediate part 31, a lower first intermediate part 32, and a second intermediate part 33), and joining a plurality of intermediate parts to each other. Welding for manufacturing the impact-absorbing member 6 is facilitated when the shock-absorbing member forming steps S13 and S23 for forming the long-shaped impact-absorbing member 6 are performed. That is, when manufacturing the impact absorbing member 6 by arranging a required number of small parts, a jig for positioning is required for each small part, and a large number of positioning pins are required. However, when a plurality of intermediate parts are welded together to manufacture the shock absorbing member 6 as in this embodiment, the number of positioning jigs and positioning pins is reduced, so welding is facilitated as described above. Become.

As a method of manufacturing the shock absorbing member 6, as shown in FIGS. 13 and 14, a step of forming a plurality of closed cross-section half portions (first closed cross-section half portion 17 and second closed cross-section half portion 18). By adopting the method including S31 and step S32 of forming the long shock absorbing member 6, the long length can be formed in the next step after forming the closed cross-section half portion without going through the step of forming the intermediate part. It is possible to form a shock absorbing member 6 having a shape. This eliminates the need for welding equipment such as a welding jig for forming intermediate parts, and the impact absorbing member 6 can be manufactured at low cost. Also, since the step of molding an intermediate part is omitted, productivity is improved.

The manufacturing method of the side sill 4 according to this embodiment includes, as shown in FIG. is a method implemented by a step S43 of joining the . Therefore, since the inner side sill 7 can be welded to the body frame 1 of the automobile in advance and supported by the body frame 1, the positions of the impact absorbing member 6 and the outer side sill 8 when welding to the inner side sill 7 can be adjusted. Easy to do. As a result, the work of mounting the side sill 4 on the vehicle body is facilitated.

(Second embodiment)
The impact absorbing member 6 can be configured as shown in FIGS. 22(A), (B) to 24(A) to (E). 22(A) is a perspective view showing the first closed cross-section half 17, and FIG. 22(B) is a perspective view showing the second closed cross-section half 18. FIG. FIG. 23(A) is a perspective view showing another embodiment of the shock absorbing member, and FIG. 23(B) is a perspective view showing the vertical positions of the upper and lower surfaces of the hollow body and the connecting piece. FIG. 24A shows an example in which two corners are provided on each of the upper and lower sides of the closed cross section 16, and FIGS. FIG. 24E shows an example in which five corners are provided on each of the upper and lower sides of the closed cross section 16. FIG. 22 to 24, the same or similar members as those explained with reference to FIGS. 1 to 21 are denoted by the same reference numerals, and detailed explanation thereof will be omitted as appropriate.

22(A) and 22(B), the first and second closed cross section forming half portions 17 and 18 have two corner portions 51 and 51 between the hat portions 17a and 18a and the collar portions 17b and 18b. A groove 52 having a is press-molded. The grooves 52 having the corners 51 are formed by press-molding the base ends of the flanges 17b and 18b (ends on the side of the hat portions 17a and 18a) in a direction in which the height of the hat portions 17a and 18a increases. there is The corners 51 positioned on both sides of the groove 52 have ridgelines 53 extending in the vehicle width direction. Hereinafter, the corner portion 51 having the ridgeline 53 is simply referred to as the "corner edge 51".

When the first closed cross-section half portion 17 and the second closed cross-section half portion 18 having the corner ridge 51 are combined, as shown in FIG. Two angular ridges 51 are provided at a time. As shown in FIG. 23(B), the closed cross-section structure 19 according to this embodiment has a connection piece 15 aligned with the upper surface 14a or the lower surface 14b of the hollow body 14. As shown in FIG. The upper surface 14a and the connecting piece 15 are offset by a dimension A in the vertical direction. The lower surface 14b and the connecting piece 15 are offset by a dimension B in the vertical direction. The upper surface 14a, the lower surface 14b, and the connection piece 15 are arranged in the longitudinal direction along the side sill inner 7 while being vertically offset.

The impact absorbing member 6 with the added corner ridges 51 in this way has a greater energy absorption capacity than the impact absorbing member 6 when adopting the first embodiment. This is because the strength of the corner ridge 51 increases, and the energy for buckling it increases.
Although not shown, the corner ridge 51 may be provided on either one of the upper side and the lower side of the closed cross section 16 . The energy absorption amount of the impact absorbing member 6 can be increased only by forming the grooves 52 during press molding.

The corner ridge 51 can be provided as shown in FIGS. 24(A) to (E). That is, as shown in FIG. 24(A), the corner ridge 51 is formed by recessing the groove 52 and forming the upper side and the lower side so that the closed section 16 is enlarged in the vertical direction. and at both ends of the lower side. Further, as shown in FIG. 24(B), the corner ridge 51 is formed by press-molding two grooves 52 to form an upper side and a lower side so that the closed cross section 16 is enlarged in the vertical direction. The central portion of is recessed inside the closed cross-section 16 to have a rectangular cross-section, and six such cross-sections can be provided on each of the upper side and the lower side.
In FIG. 24C, a step shape is added to one side of the groove 52 to form an upper side and a lower side so that the closed cross section 16 is expanded in the vertical direction, and the upper side and the lower side are formed in a stepped shape to form corners. An example in which six ridges 51 are provided on each of the upper side and the lower side is shown.

24(D), a small groove is press-formed on the bottom surface of the groove 52 to form an upper side and a lower side so that the closed cross section 16 is expanded in the vertical direction, and the central portion of the upper side and the lower side is rectangular in cross section. shows an example in which six ridges 51 are provided on each of the upper side and the lower side by protruding to the outside of the closed cross section 16 .
In FIG. 24(E), the groove 52 is press-molded so as to bulge the center of the bottom surface to form an upper side and a lower side so that the closed cross section 16 is expanded in the vertical direction, and the central portion of the upper side and the lower side is formed. An example in which five ridges 51 are provided on each of the upper side and the lower side by recessing a V-shaped cross section is shown.

REFERENCE SIGNS LIST 1 automobile body frame 3 center pillar inner 5 side sill structure 6 impact absorbing member 7 side sill inner 8 side sill outer 12 holding member 14 hollow body 15 connecting piece 16 Closed section 17 First closed section forming half portion 18 Second closed section forming half portion 17a, 18a Cap portion 17b, 18b Collar portion 21 Top portion 23 (Sill outer) Fixing member 51... Corner, corner edge, 52... Groove, 53... Ridgeline, S1, S11, S21, S31... Step of forming a plurality of closed cross-section half parts, S2... Step of forming a closed cross-section structure, S3... Step of forming a long shock absorbing member, S12, S22... Step of forming an intermediate part, S13, S23... Step of joining the intermediate parts together to form a long shock absorbing member, S32... Step of joining closed cross section halves to form a shock absorbing member, S42: Joining the side sill outer to the shock absorbing member, S43: Joining the side sill outer and the side sill inner, S51: Impact on the side sill inner. A step of joining the absorbing member, S52 ... a step of joining the side sill outer to the side sill inner.

Claims (13)

a step of forming a closed cross-section half portion by press-molding a steel plate blank into a hat-shaped cross-section having a hat portion and a pair of brim portions to form a closed cross-section half portion;
At least two of the closed cross-section halves are combined so that the convex directions of the cap portions are opposite to each other, and the top of the cap portion of one of the closed cross-section halves and the other of the closed cross-section halves. a step of forming a plurality of closed cross-section structures that are overlapped and joined to the flange portion of to form a plurality of closed cross-section structures that are connected only in the longitudinal direction by connecting pieces ;
forming a shock absorbing member by
The cap portion has at least a pair of corner ridges orthogonal to the longitudinal direction,
The body having a closed cross section has a connection piece aligned with the upper surface or the lower surface of the hollow body, and the upper surface and the connection piece, and the lower surface and the connection piece are arranged in the longitudinal direction in a vertically offset state.
A method for manufacturing a shock absorbing member characterized by: A closed cross-section half portion is added to the closed cross-section structure body and combined in such a manner that the convex directions of the adjacent cap portions are opposite to each other. 2. Manufacturing the impact absorbing member according to claim 1, wherein the flange part of the closed cross-section half part is overlapped and joined to form a second closed cross-section body, which has a hollow structure with a substantially inverted V shape when viewed from the cross-sectional direction. Method. 2. The method of manufacturing a shock absorbing member according to claim 1, wherein said closed cross-section half portion is formed continuously in common to a plurality of hat portions and brim portions. 2. The shock absorber according to claim 1, wherein the closed section structure body is formed by varying the vertical and horizontal dimensions, the plate thickness, and the material of one or both of the cap portion or brim portion of each of the closed section structure half portions. The manufacturing method of the member. A first intermediate part in which a plurality of the cap parts are arranged in the longitudinal direction of the shock absorbing member, and upper and/or lower shock absorbing parts connected by a brim part are formed as a first intermediate part. a forming step;
The upper and lower shock absorbing portions are combined in such a manner that the convex directions of the cap portion are opposite to each other, and the top portion of the cap portion of one half portion having a closed cross section and the brim of the other half portion having a closed cross section. 2. The method of manufacturing a shock absorbing member according to claim 1, further comprising a step of forming a shock absorbing member by overlapping and joining the portions to form a closed cross-section structure and joining together to form a long shock absorbing member. A plurality of the closed cross-section halves are combined so that the convex directions of the cap portions are opposite to each other, and the top of the cap portion of one of the closed cross-section halves is the other of the closed cross-section halves. a second intermediate component forming step of forming at least two or more second intermediate components by overlapping and joining with the collar;
The at least two or more second intermediate parts are joined by overlapping the top of the hat portion of one of the second intermediate parts and the flange of the other second intermediate part to form an elongated impact. 2. The method of manufacturing a shock absorbing member according to claim 1, further comprising a shock absorbing member forming step of forming the shock absorbing member. In the step of forming the closed cross-section body, the closed cross-section halves of the impact absorbing member are arranged in a state in which the closed cross-section halves are not joined to each other, and the adjacent cap portions have convex directions opposite to each other. Combined as a posture to become
2. The method of manufacturing a shock absorbing member according to claim 1, wherein the top portion of the cap portion of the closed cross-section half portion is overlapped and joined to the brim portion of the adjacent closed cross-section half portion in an opposite posture. Forming at least one or more grooves adjacent to or not adjacent to the hat portion in at least one or both of the flange portions and adding a corner ridge extending in the left-right direction to the closed cross-section structure along the hollow structure; A method for manufacturing the impact absorbing member according to claim 1. 9. The method of manufacturing an impact absorbing member according to claim 8, wherein one or more of a step shape, a smaller groove, two or more small second grooves, and a raised portion are added to the groove. 2. The impact absorbing member according to claim 1, further comprising a fixed member projecting outward from a closed cross-section comprising inclined walls of hat portions facing each other and brim portions facing each other of said closed cross-section forming half portion of said impact absorbing member. Production method. a step of joining a shock absorbing member formed by the manufacturing method of a shock absorbing member according to any one of claims 1 to 10 to a side sill outer;
A method of manufacturing a side sill, comprising: joining the side sill outer to which the shock absorbing member is joined and the side sill inner. a step of joining a shock absorbing member formed by the method for manufacturing a shock absorbing member according to any one of claims 1 to 10 to a side sill inner;
A method for manufacturing a side sill, comprising: joining the inner side sill to which the shock absorbing member is joined and the outer side sill. A closed section structure body formed by combining a plurality of closed section structure halves made of a steel plate having a hat-shaped cross section and having a cap portion and a pair of brim portions,
The cap portion has at least a pair of corner ridges perpendicular to the longitudinal direction,
At least two of the closed cross-section halves are combined in such a manner that the convex directions of the cap portion are opposite to each other ,
the top portion of the cap portion of one of the closed cross-section half portions and the brim portion of the other closed cross-section half portion are overlapped and joined,
The body having a closed cross-section has a hollow body and a connection piece aligned with the upper surface or the lower surface of the hollow body,
a plurality of the closed cross-section structures are connected only in the longitudinal direction by the connecting pieces,
The upper surface and the connection piece, and the lower surface and the connection piece are arranged in a longitudinal direction along the side sill inner in a vertically offset state,
A shock absorbing member characterized by:

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