WO2016084776A1

WO2016084776A1 - Vehicle impact beam and production method for same

Info

Publication number: WO2016084776A1
Application number: PCT/JP2015/082867
Authority: WO
Inventors: 幸平程谷; 雅宏橋口; 正史佐伯; 中村　祐一
Original assignee: アイシン精機株式会社
Priority date: 2014-11-25
Filing date: 2015-11-24
Publication date: 2016-06-02
Also published as: JP2016097860A

Abstract

Provided is a vehicle impact beam that has an open cross-sectional shape, that has a main body section that is integrally formed with a pair of terminal sections, and that has increased strength. This vehicle impact beam is provided with an elongate main body section and with a pair of terminal sections that are connected to both longitudinal-direction ends of the main body section. The main body section and the pair of terminal sections are integrally formed by deforming a metallic steel sheet. As seen from the longitudinal direction, the main body section has an open cross-sectional shape, has a main-body-side protrusion that protrudes in a prescribed direction, and has a pair of inner flange parts that are provided so as to extend toward each other from both side ends of the main-body-side protrusion. As seen from the longitudinal direction of the main body section, the terminal sections have an open cross-sectional shape, have a terminal-side protrusion that protrudes in the same direction as the protrusion direction of the main-body-side protrusion, and have a pair of outer flange parts that are provided so as to extend away from each other from both sides of the terminal-side protrusion.

Description

Vehicle impact beam and manufacturing method thereof

The present invention relates to an impact beam for a vehicle and a manufacturing method thereof.

A reinforcing member called a vehicle impact beam is disposed inside the vehicle door. The vehicle impact beam suppresses deformation of the vehicle door when an impact load is applied to the vehicle door from the outside.

A vehicle impact beam is generally formed in a long shape, and includes a long main body portion that mainly functions as a reinforcing member, and a pair of terminal portions connected to both ends in the longitudinal direction of the main body portion. . The pair of terminal portions are joined to the inner panel of the vehicle door by joining means such as welding, whereby the vehicle impact beam is fixed in the vehicle door.

Patent Document 1 discloses a vehicle impact beam including a main body portion constituted by two pipes arranged in parallel to each other and a pair of terminal portions respectively attached to both ends in the longitudinal direction of the main body portion. Patent Document 2 discloses a vehicle impact beam in which a main body portion having an open cross-sectional shape and a pair of terminal portions are integrally formed by press molding. According to Patent Document 2, a vehicle impact beam is press-molded in a press mold, and heat treatment is performed following the press molding. By such a die quench method, it is possible to easily manufacture a vehicle impact beam with increased hardness.

JP 2006-35868 A JP 2010-195187 A

(Problems to be solved by the invention)
The pair of terminal portions of the impact beam for a vehicle described in Patent Document 1 are separate parts from the main body portion. Therefore, the number of component parts is increased as compared with the impact beam in which the main body part and the pair of terminal parts are integrally formed, and therefore the part cost and the assembling cost are increased.

In addition, since the vehicle impact beam described in Patent Document 2 is integrally formed by press molding of the main body portion and the pair of terminal portions, the component cost and the assembling cost are compared with the case where these are separate components. Can be suppressed. However, since the cross-sectional shape of the vehicle impact beam described in Patent Document 2 is an open cross-sectional shape, there is a problem that the strength is low.

An object of the present invention is to provide a vehicle impact beam having an open cross-sectional shape, in which a main body portion and a pair of terminal portions are integrally formed, and having increased strength, and a method for manufacturing the same.

(Means for solving the problem)
The present invention includes an elongated body portion (2) disposed inside a vehicle door (DR) and a pair of terminal portions (3, 4) connected to both ends in the longitudinal direction of the body portion. The vehicle impact beam (1) includes a main body portion and a pair of terminal portions that are integrally formed by deforming a metal steel plate, and the main body portion has a predetermined shape when viewed from the longitudinal direction thereof. The main body side convex portion (21) projecting in the direction and the pair of inner flange portions (22) extending in the direction approaching each other from both ends of the main body side convex portion, and the cross-sectional shape perpendicular to the longitudinal direction is open The terminal portion is configured to have a cross-sectional shape, and the terminal portion protrudes in the same direction as the protruding direction of the main body side convex portion when viewed from the longitudinal direction of the main body portion, and the terminal side convex portion A pair that extends away from both ends of the It has an outer flange section (32, 42), and configured such that the cross-sectional shape perpendicular to the longitudinal direction is in the open cross-sectional shape, to provide a vehicle impact beam.

According to the present invention, since the main body part and the pair of terminal parts of the vehicle impact beam are integrally formed by deforming the metal steel plate, the main body part and the pair of terminal parts are separate parts. In comparison, component costs and assembly costs can be reduced. The main body portion includes a main body side convex portion and an inner flange portion, and is configured such that a cross-sectional shape perpendicular to the longitudinal direction is an open cross-sectional shape. The main body side convex portion is configured to have a convex shape protruding in a predetermined direction when viewed from the longitudinal direction of the main body portion. Further, the inner flange portion extends in a direction approaching each other from both side ends (end portions formed along the longitudinal direction) of the main body side convex portion when viewed from the longitudinal direction of the main body portion. By forming such an inner flange portion, an impact was applied from the direction orthogonal to the longitudinal direction of the main body portion, particularly from the direction opposite to the protruding direction of the main body side convex portion toward the main body side convex portion. The cross-sectional deformation of the main body portion in the case is suppressed. That is, the strength of the vehicle impact beam can be increased by forming the inner flange portion. Therefore, according to the present invention, it is possible to provide a vehicle impact beam having an open cross-sectional shape, in which a main body portion and a pair of terminal portions are integrally formed and strength is increased.

Also, the terminal portion has a terminal-side convex portion and an outer flange portion. The terminal-side convex portion is configured to have a convex shape protruding in the same direction as the protruding direction of the main body-side convex portion when viewed from the longitudinal direction of the main body portion. When viewed from the longitudinal direction of the main body portion, the outer flange portion is extended in a direction opposite to the extending direction of the inner flange portion, that is, a direction away from each other, from both side ends of the terminal-side convex portion. By connecting the outer flange portion to, for example, the inner panel of the vehicle door, the vehicle impact beam can be fixed to the vehicle door.

In the present invention, regarding the pair of inner flange portions, “extended in a direction approaching each other” means that an extension line extending in the extending direction of one inner flange portion as viewed from the longitudinal direction of the main body portion and the other This means that the pair of inner flange portions are respectively extended so that the extension lines extending in the extending direction of the inner flange portions of the inner flange portions intersect. In addition, regarding the pair of outer flange portions, “extended in a direction away from each other” means that an extension line extending in the extending direction of one outer flange portion when viewed from the longitudinal direction of the main body portion and the other flange portion This means that the pair of outer flange portions are extended so that the extension lines extending in the extending direction do not intersect.

In this case, when viewed from the longitudinal direction of the main body portion, the main body side convex portion extends from the both ends of the main body side outer wall portion (211) and the main body side outer wall portion facing each other in a direction facing each other. A pair of body side wall portions (212) provided, and the pair of inner flange portions (22) are arranged so as to approach each other from the extended ends of the pair of body side wall portions when viewed from the longitudinal direction of the body portion. Each should be extended. In addition, the terminal-side convex portion is a direction facing each other from both ends of the terminal-side outer wall portion (311 411) and the terminal-side outer wall portion having a surface perpendicular to the protruding direction when viewed from the longitudinal direction of the main body portion. The pair of terminal side wall portions (312 and 412) are extended, and the pair of outer flange portions (32 and 42) are extended ends of the pair of terminal side wall portions when viewed from the longitudinal direction of the main body portion. It is good to extend in the direction away from each other.

In the above invention, with respect to the pair of main body side wall portions, “extending in a direction facing each other” means that the pair of main body side wall portions includes the same direction component from both side ends of the main body side outer wall portion. It means that they are extended together. Similarly, with respect to the pair of terminal side wall portions, “extending in a direction facing each other” means that the pair of terminal side wall portions are in the direction including the same direction component from both side ends of the terminal side outer wall portion. , Means that both are extended.

Further, it is preferable that the main body portion is heat-treated and the pair of terminal portions are not heat-treated. According to this, the strength of the main body portion can be further improved by applying heat treatment to the main body portion to increase the hardness of the main body portion. The terminal portion is a portion connected to the vehicle door, and such a terminal portion is required to have high toughness (toughness) rather than high hardness. When the member is heat treated, the hardness is increased, but the toughness is reduced. When the toughness is lowered by applying heat treatment to the terminal portion, the terminal portion may be broken by an impact and the vehicle impact beam may be detached from the vehicle door. On the other hand, when heat treatment is not performed on the terminal portion, the terminal portion may be plastically deformed by impact, but since a decrease in toughness is suppressed, defects such as cracks do not occur. Thus, according to the present invention, cracking of the terminal portion when an impact load is applied is effectively prevented by suppressing a decrease in toughness without subjecting the pair of terminal portions to heat treatment.

Also, the vehicle impact beam according to the present invention may be attached to the vehicle door such that the protruding direction of the main body side convex portion and the terminal side convex portion is outward in the vehicle width direction. According to this, when an impact load is applied to the vehicle door inwardly in the vehicle width direction, that is, in a direction opposite to the protruding direction of the main body side convex portion and the terminal side convex portion, the effect is exerted by the vehicle impact beam. Therefore, deformation of the vehicle door is suppressed.

The present invention also relates to a method for manufacturing an impact beam for a vehicle, which is formed by roll forming a metal steel plate, and is a long projection that protrudes in a predetermined direction when viewed from the longitudinal direction (61 ) And a pair of inner flange portions (62) extending in a direction approaching from both ends of the convex portion (61), and a cross-sectional shape perpendicular to the longitudinal direction is an open cross-sectional shape. The roll forming step to be produced and the heat-treated portion subjected to heat treatment and the non-heat-treated portion not subjected to heat treatment are roll-formed along the longitudinal direction by partially heat-treating the roll-formed product along the longitudinal direction. The convex part (71) in which the partial heat treatment process alternately formed on the product and the non-heat treatment part project in the same direction as the projection direction of the convex part formed in the heat treatment part when viewed from the longitudinal direction, and its Convex ( 1) Deformation step of deforming a non-heat-treated portion so that it has a pair of outer flange portions (72) extending in a direction away from both side ends of 1), and the cross-sectional shape perpendicular to the longitudinal direction is an open / close cross-sectional shape And a method for manufacturing an impact beam for a vehicle.

According to the present invention, the convex portion and the inner flange portion are continuously formed along the longitudinal direction by roll forming the metal steel plate in the roll forming step. Thereafter, in the partial heat treatment step, heat-treated portions and non-heat-treated portions are alternately formed on the roll molded product along the longitudinal direction. The non-heat treated portion has low hardness and high toughness. That is, the non-heat treated part is easily deformed. Therefore, after that, by deforming the non-heat treated portion in the deformation step, a convex portion and an outer flange portion protruding in the same direction as the convex portion formed in the heat treated portion are formed in the non-heat treated portion. The heat treatment portion corresponds to the main body portion of the vehicle impact beam, and the non-heat treatment portion corresponds to the pair of terminal portions. Thus, a vehicle impact beam manufacturing method in which the main body portion and the pair of terminal portions are integrally formed and the strength of the main body portion is increased is provided.

The deformation step may be a step of forming the outer flange portion by deforming the inner flange portion formed in the non-heat treated portion by press forming the non-heat treated portion. According to this, an inner flange part can be easily changed into an outer flange part by press-molding a non-heat-treatment part.

FIG. 1 is a side view of a vehicle equipped with a vehicle impact beam according to the present embodiment. FIG. 2 is a front view of the vehicle impact beam according to the present embodiment attached to the inner panel of the vehicle door provided in the vehicle, as viewed from the vehicle outer side in the vehicle width direction. FIG. 3 is a perspective view of a vehicle impact beam according to the present embodiment. 4 is a cross-sectional view taken along the line AA in FIG. 5 is a cross-sectional view taken along the line BB in FIG. 6 is a cross-sectional view taken along the line CC of FIG. FIG. 7 is a view showing the front end portion and the main body portion connected to the front end portion from a direction in which the inner flange portion and the front outer flange portion can be seen together. FIG. 8 is a view showing the rear end portion and the main body portion connected to the rear end portion from the direction in which the inner flange portion and the rear outer flange portion can be seen together. FIG. 9 is a diagram showing a schematic configuration of the roll forming apparatus. FIG. 10 is a diagram illustrating one aspect of the deformation of the cross-sectional shape of the non-heat treated portion of the roll-formed product when the deformation process is performed. 11 is a cross-sectional view taken along the line DD of FIG.

Hereinafter, embodiments of the present invention will be described. FIG. 1 is a side view of a vehicle equipped with a vehicle impact beam according to the present embodiment. As shown in FIG. 1, a vehicle door DR for a passenger to get on and off is attached to a side surface of the vehicle V. The vehicle impact beam 1 according to the present embodiment is disposed inside the vehicle door DR. The vehicle door DR includes an outer panel and an inner panel as is well known, and the vehicle impact beam 1 is disposed in a space between the outer panel and the inner panel. The vehicle impact beam 1 is attached to the inner panel.

FIG. 2 shows the vehicle impact beam 1 according to the present embodiment attached to the inner panel IP of the vehicle door DR provided in the vehicle V, as viewed from the outside of the vehicle V in the width direction (vehicle width direction). It is a front view. In FIG. 2, the left-right direction is the front-rear direction of the vehicle V (vehicle front-rear direction), the right side is the front, and the left is the rear. As shown in FIG. 2, the vehicle impact beam 1 extends in the vehicle front-rear direction from a position near the rear end of the inner panel IP to a position near the front end. Further, the vehicle impact beam 1 is attached to the inner panel IP in a state of being inclined so as to be directed upward as it goes forward.

FIG. 3 is a perspective view of the vehicle impact beam 1 according to the present embodiment. As shown in FIG. 3, the vehicle impact beam 1 includes an elongated main body portion 2 and a pair of terminal portions (front terminal portion 3 and rear terminal portion 4) connected to both ends in the longitudinal direction of the main body portion 2. Is provided. The pair of

terminal portions

3 and 4 are formed integrally with the main body portion 2. Here, "the body part 2 and the pair of

terminal parts

3 and 4 are molded integrally" means that the body part 2 and the

terminal parts

3 and 4 are molded without performing an assembling process or a joining process. Say. In the present embodiment, the main body portion 2 and the pair of

terminal portions

3 and 4 are integrally formed by plastically deforming a metal steel plate by roll forming.

When the vehicle impact beam 1 is mounted on the vehicle door DR of the vehicle V, the front terminal portion 3 is located on the front side of the main body portion 2 as shown in FIG. 2, and the rear terminal portion 4 is the main body portion. 2 on the rear side. At this time, the front terminal portion 3 is connected near the front end of the inner panel IP, and the rear terminal portion 4 is connected near the rear end of the inner panel IP.

FIG. 4 is a cross-sectional view taken along the line AA in FIG. FIG. 4 is a cross-sectional view of the main body portion 2 when the main body portion 2 is cut along a plane perpendicular to the longitudinal direction of the main body portion 2 of the vehicle impact beam 1 (hereinafter simply referred to as “longitudinal direction”). The shape of the main body portion 2 when viewed from the direction is represented. In FIG. 4, the left-right direction is the vehicle width direction, the left side is outward, and the right side is inward. Here, “outward” in the vehicle width direction is a direction from the vehicle inner side to the vehicle outer side of the vehicle V, and “inward” in the vehicle width direction is a direction from the vehicle outer side of the vehicle V to the vehicle inner side. It is. Further, the direction perpendicular to the paper surface of FIG. 4 is the longitudinal direction. The longitudinal direction is orthogonal to the vehicle width direction. Further, the vertical direction in FIG. 4, that is, the direction orthogonal to the longitudinal direction and the vehicle width direction is defined as the beam width direction.

As shown in FIG. 4, the main body portion 2 is disposed outside the inner panel IP in the vehicle width direction. The main body portion 2 has a main body-side convex portion 21 and a pair of

inner flange portions

22 and 22, and a cross-sectional shape perpendicular to the longitudinal direction is an open cross-sectional shape, that is, a cross-sectional shape in which a closed space is not formed inside Configured to be. The main body side convex portion 21 is configured to have a convex shape protruding outward in the vehicle width direction (arrow D direction) when viewed from the longitudinal direction. Such a convex shape is continuously formed along the longitudinal direction as shown in FIG.

The main body side convex portion 21 has a main body side outer wall portion 211 and a pair of main body

side wall portions

212 and 212. The main body side outer wall portion 211 constitutes the outermost portion of the main body side convex portion 21 in the vehicle width direction. The main body-side outer wall portion 211 extends in the beam width direction in the cross section shown in FIG. 4 and has a surface substantially perpendicular to the arrow D direction (outward in the vehicle width direction) in FIG. In the present embodiment, a hollow portion 211a that is recessed inward in the vehicle width direction is provided at an intermediate position in the beam width direction of the main body side outer wall portion 211. The recess 211a is continuously formed along the longitudinal direction. Therefore, in the present embodiment, the two convex shapes partitioned by the recessed portion 211a are continuously formed in the main body portion 2 along the longitudinal direction in parallel with each other. By forming such a recessed portion 211a in the main body portion 2 and complicating the cross-sectional shape of the main body portion 2, the strength, particularly the bending strength, of the main body portion 2 can be increased.

The pair of main body

side wall portions

212 and 212 are formed from both side ends (end portions formed along the longitudinal direction) of the main body side outer wall portion 211 in the beam width direction, that is, from the upper end and the lower end of the main body side outer wall portion 211 in FIG. These are extended in the direction facing each other, specifically in the direction including the inward component in the vehicle width direction. In the present embodiment, as shown in FIG. 4, the pair of main body

side wall portions

212, 212 extend slightly open so that the distance between the two increases gradually toward the inside in the vehicle width direction. Is done.

Further, the pair of

inner flange portions

22 and 22 are extended from both side ends (end portions formed along the longitudinal direction) of the main body side convex portion 21 when viewed from the longitudinal direction. Specifically, as shown in FIG. 4, the pair of

inner flange portions

22, 22 are arranged in a direction approaching each other from the inner ends in the vehicle width direction, which are extended ends of the pair of main body

side wall portions

212, 212. , Respectively. More specifically, the inner flange portion 22 formed from the extending end (inward end) of the lower main body side wall portion 212 in FIG. 4, the inner flange portion 22 formed from the extending end (inward end) of the upper main body side wall portion 212 extends downward in FIG. Therefore, the pair of

inner flange portions

22 and 22 sinks into the region between the extended ends (inward ends) of the pair of main body

side wall portions

212 and 212 in the beam width direction, that is, inside the main body side convex portion 21. As such, it is extended. In the present embodiment, the pair of

inner flange portions

22, 22 are bent at substantially right angles so as to sink into the inside of the main body side convex portion 21 from the extended ends of the pair of main body

side wall portions

212, 212. Yes. The pair of

inner flange portions

22 and 22 having such a shape is continuously formed along the longitudinal direction.

Since the pair of

inner flange portions

22 and 22 are extended in the direction approaching each other as described above, from the position outside the main body portion 2 in the vehicle width direction (for example, the position represented by the point P in FIG. 4), When the main body portion 2 is viewed along the inner side in the vehicle width direction, the pair of

inner flange portions

22 and 22 are hidden behind the main body side convex portion 21 and cannot be seen. That is, the pair of

inner flange portions

22, 22 are extended in a direction hidden by the main body side convex portion 21 when the main body portion 2 is viewed from a position outside the main body portion 2 in the vehicle width direction. Such a portion extending so as to be hidden by another portion when viewed from a certain direction is called a negative angle portion. That is, the “inner flange portion” constitutes a negative angle portion with respect to the inner side in the vehicle width direction.

Further, as shown in FIG. 4, a gap G is formed between the tip of one inner flange portion 22 and the tip of the other inner flange portion 22. The gap G is formed at a position facing the main body side outer wall portion 211.

FIG. 5 is a cross-sectional view taken along the line BB in FIG. FIG. 5 is a cross-sectional view of the front terminal portion 3 when the front terminal portion 3 is cut along a plane perpendicular to the longitudinal direction, and shows the shape of the front terminal portion 3 when viewed from the longitudinal direction. In FIG. 5, the left-right direction is the vehicle width direction, the left side is outward, and the right side is inward. Further, the direction perpendicular to the paper surface of FIG. 5 is the longitudinal direction, and the vertical direction is the beam width direction.

As shown in FIG. 5, the front terminal portion 3 is arranged outside the inner panel IP in the vehicle width direction, like the main body portion 2. The front end portion 3 has a front end side convex portion 31 (terminal side convex portion) and a pair of front

outer flange portions

32 and 32, and is configured such that a cross-sectional shape perpendicular to the longitudinal direction is an open cross-sectional shape. Is done. When viewed from the longitudinal direction, the front end convex portion 31 is configured to have a convex shape that protrudes in the same direction as the protruding direction of the main body convex portion 21, that is, outward in the vehicle width direction (arrow D direction). The Such a convex shape is continuously formed along the longitudinal direction.

The front end side convex portion 31 has a front end side outer wall portion 311 (terminal side outer wall portion) and a pair of front end side wall portions 312 and 312 (terminal side side wall portions). The front end side outer wall portion 311 constitutes the outermost part of the front end side convex portion 31 in the vehicle width direction. The front end side outer wall portion 311 extends in the beam width direction in the cross section shown in FIG. 5 and has a surface substantially perpendicular to the arrow D direction (outward in the vehicle width direction) of FIG. In the present embodiment, a recessed portion 311a that is recessed inward in the vehicle width direction is provided at an intermediate position in the beam width direction of the front end side outer wall portion 311. The recess 311a is continuously formed along the longitudinal direction. Therefore, in this embodiment, the two convex shapes partitioned by the recess 311a are continuously formed in the front end portion 3 along the longitudinal direction in parallel with each other.

The pair of front end

side wall portions

312 and 312 are opposed to each other from both side ends of the front end side outer wall portion 311 in the beam width direction, that is, the upper end and the lower end of the front end side outer wall portion 311 in FIG. Both are extended in the direction including the inner component in the direction.

Further, the pair of front

outer flange portions

32, 32 are extended from both side ends of the front end convex portion 31 when viewed from the longitudinal direction. Specifically, as shown in FIG. 5, the pair of front

outer flange portions

32, 32 are directions away from the inner ends in the vehicle width direction, which are extended ends of the pair of front end

side wall portions

312, 312. Respectively. More specifically, the front outer flange portion 32 formed from the extended end (inward end) of the lower front end side wall portion 312 in FIG. 5, the front outer flange portion 32 formed from the extending end (inward end) of the upper front end side wall portion 312 is extended upward in FIG. . Accordingly, the pair of front

outer flange portions

32, 32 are extended outside the region between the extended ends (inner ends) of the pair of front end

side wall portions

312, 312 in the beam width direction. The pair of front

outer flange portions

32, 32 having such a shape is continuously formed along the longitudinal direction.

Since the pair of front

outer flange portions

32, 32 are extended in the direction away from each other as described above, they are positioned outside the front terminal portion 3 in the vehicle width direction (for example, the position represented by the point Q in FIG. 5). Thus, when the front terminal portion 3 is viewed along the inner side in the vehicle width direction, the pair of front

outer flange portions

32 and 32 can be visually recognized without being hidden by the front end convex portion 31. In other words, the pair of front

outer flange portions

32, 32 extend in a direction that is not hidden by the front end convex portion 31 when the front terminal portion 3 is viewed from a position outside the front terminal portion 3 in the vehicle width direction. .

Also, the pair of front

outer flange portions

32, 32 are brought into face contact with the surfaces of the inner panel IP facing outward in the vehicle width direction. And a pair of front side

outer flange parts

32 and 32 are each fixed to the front part of inner panel IP by fixing means, such as spot welding.

FIG. 6 is a cross-sectional view taken along the line CC of FIG. FIG. 6 is a cross-sectional view of the rear terminal portion 4 when the rear terminal portion 4 is cut along a plane perpendicular to the longitudinal direction, and shows the shape of the rear terminal portion 4 when viewed from the longitudinal direction. In FIG. 6, the left-right direction is the vehicle width direction, the left side is outward, and the right side is inward. Further, the direction perpendicular to the paper surface of FIG. 6 is the longitudinal direction, and the vertical direction is the beam width direction.

As shown in FIG. 6, the rear terminal portion 4 is disposed outside the inner panel IP in the vehicle width direction, like the main body portion 2 and the front terminal portion 3. The rear terminal portion 4 includes a rear end convex portion 41 (terminal side convex portion) and a pair of rear

outer flange portions

42 and 42, and a cross-sectional shape perpendicular to the longitudinal direction is an open cross-sectional shape. Configured as follows. The rear end side convex portion 41 is configured to have a convex shape that protrudes outward in the vehicle width direction (arrow D direction) in the same direction as the protruding direction of the main body side convex portion 21 when viewed from the longitudinal direction. Is done. Such a convex shape is continuously formed along the longitudinal direction.

The rear end side convex part 41 has a rear end side outer wall part 411 (terminal side outer wall part) and a pair of rear end side wall parts 412 and 412 (terminal side side wall parts). The rear end side outer wall portion 411 constitutes the outermost portion of the rear end side convex portion 41 in the vehicle width direction. The rear end side outer wall portion 411 extends in the beam width direction in the cross section shown in FIG. 6 and has a surface substantially perpendicular to the arrow D direction (outward in the vehicle width direction) of FIG. In the present embodiment, a recessed portion 411a that is recessed inward in the vehicle width direction is provided at an intermediate position in the beam width direction of the rear end side outer wall portion 411. The depression 411a is continuously formed along the longitudinal direction. Therefore, in this embodiment, two convex shapes partitioned by the recessed portion 411a are continuously formed in the rear terminal portion 4 along the longitudinal direction in parallel with each other.

The pair of rear end

side wall portions

412 and 412 are in a direction facing each other from both side ends of the rear end side outer wall portion 411 in the beam width direction, that is, from the upper end and the lower end of the rear end side outer wall portion 411 in FIG. Are extended in the direction including the inward component in the vehicle width direction.

Further, the pair of rear

outer flange portions

42, 42 are extended from both side ends of the rear end convex portion 41 when viewed from the longitudinal direction. Specifically, as shown in FIG. 6, the pair of rear

outer flange portions

42, 42 are mutually connected from the inner ends in the vehicle width direction, which are the extended ends of the pair of rear end

side wall portions

412, 412. Each is extended in the direction away. More specifically, the rear outer flange portion 42 formed from the extending end (inner end) of the lower rear end side wall portion 412 in FIG. 6 among the pair of rear end

side wall portions

412 and 412. 6 extends downward in FIG. 6, and the rear outer flange portion 42 formed from the extended end (inward end) of the upper rear end side wall 412 extends upward in FIG. 6. It is extended to. Accordingly, the pair of rear

outer flange portions

42, 42 extend outside the region between the extended ends (inward ends) of the pair of rear end

side wall portions

412, 412 in the beam width direction. The pair of rear

outer flange portions

42, 42 having such a shape is continuously formed along the longitudinal direction.

Since the pair of rear

outer flange portions

42 and 42 are extended in the direction away from each other as described above, they are positioned outside the rear terminal portion 4 in the vehicle width direction (for example, represented by a point R in FIG. 6). When the rear terminal portion 4 is viewed from the position inward in the vehicle width direction, the pair of rear

outer flange portions

42 and 42 can be visually recognized without being hidden by the rear end convex portion 41. That is, the pair of rear

outer flange portions

42, 42 are in a direction not hidden by the rear end convex portion 41 when the rear terminal portion 4 is viewed from a position outside the rear terminal portion 4 in the vehicle width direction. It is extended.

Also, the pair of rear

outer flange portions

42, 42 are brought into face contact with the outwardly facing surfaces of the inner panel IP in the vehicle width direction. And a pair of rear side

outer flange parts

42 and 42 are each fixed to the rear part of inner panel IP by fixing means, such as spot welding.

FIG. 7 is a view showing the front terminal portion 3 and the main body portion 2 connected thereto from a direction in which the inner flange portion 22 and the front outer flange portion 32 can be seen together. As shown in FIG. 7, a notch C <b> 1 is formed between one inner flange portion 22 a formed in the main body portion 2 and one front outer flange portion 32 a formed in the front terminal portion 3. The inner flange portion 22a and the front outer flange portion 32a are formed side by side in the longitudinal direction with the notch C1 as a boundary. Similarly, a notch C <b> 2 is formed between the other inner flange portion 22 b formed in the main body portion 2 and the other front outer flange portion 32 b formed in the front terminal portion 3. The inner flange portion 22b and the front outer flange portion 32b are formed side by side in the longitudinal direction with the notch C2 as a boundary.

FIG. 8 is a view showing the rear terminal portion 4 and the main body portion 2 connected thereto from a direction in which the inner flange portion 22 and the rear outer flange portion 42 can be seen together. As shown in FIG. 8, a notch C <b> 3 is formed between one inner flange portion 22 a formed in the main body portion 2 and one rear outer flange portion 42 a formed in the rear terminal portion 4. The inner flange portion 22a and the rear outer flange portion 42a are formed side by side in the longitudinal direction with the notch C3 as a boundary. Similarly, a cut C4 is formed between the other inner flange portion 22b formed in the main body portion 2 and the other rear outer flange portion 42b formed in the rear terminal portion 4. The inner flange portion 22b and the rear outer flange portion 42b are formed side by side in the longitudinal direction with the notch C4 as a boundary.

Further, as well shown in FIG. 3, the main body side convex portion 21 formed on the main body portion 2, the front end side convex portion 31 formed on the front terminal portion 3, and the rear terminal portion 4 are formed. The rear end convex part 41 is continuously connected along the longitudinal direction. Similarly, a recess 211a formed in the main body side outer wall portion 211 of the main body portion 2, a recess portion 311a formed in the front end side outer wall portion 311 of the front terminal portion 3, and the rear end side of the rear terminal portion 4 The recessed part 411a formed in the outer wall part 411 is continuously connected along the longitudinal direction. Therefore, in the vehicle impact beam 1 according to the present embodiment, the two convex portions are continuously formed over the entire region along the longitudinal direction while maintaining a parallel relationship with each other.

Moreover, the main body portion 2 is subjected to heat treatment. For this reason, the hardness of the main-body part 2 is raised. On the other hand, the pair of

terminal portions

3 and 4 are not heat-treated. For this reason, the hardness of the pair of

terminal portions

3 and 4 is not increased.

In the vehicle V including the vehicle door DR to which the vehicle impact beam 1 having the above configuration is attached, when an impact load is applied to the vehicle door DR from the outside to the inside of the vehicle door DR in the vehicle width direction. The impact load also acts on the vehicle impact beam 1 in the vehicle door DR. At this time, the impact load acts on the main body side outer wall portion 211 arranged on the outermost side of the main body side convex portion 21 of the main body portion 2 of the vehicle impact beam 1. The main body side outer wall portion 211 is pressed inward in the vehicle width direction by an impact load.

When a portion in the longitudinal direction of the main body side outer wall portion 211 is pressed by an impact load, the main body portion 2 tends to be bent so that the main portion 2 is bent at that portion. Further, along with such bending, the pair of main body

side wall portions

212 and 212 falls in a direction in which the distance between the extended ends of the two main body side walls 212 increases, that is, in the opening direction, and the main body side convex portion 21 tends to collapse. Here, the pair of inner flange portions 22 are mutually connected from the main body side convex portion 21 (main body side wall portion 212) so as to form a negative angle portion with respect to the acting direction of the impact load (inward in the vehicle width direction). It extends in the approaching direction. By forming such a negative angle portion, the cross-sectional shape of the main body portion 2 is made close to a closed cross-sectional shape having a higher strength (a cross-sectional shape forming a closed space inside). The pair of

inner flange portions

22 and 22 support the pair of main body

side wall portions

212 and 212, thereby preventing the pair of main body

side wall portions

212 and 212 from falling down. For this reason, the deformation | transformation of the main body side convex part 21 by an impact load is suppressed. That is, by providing the main body portion 2 with the inner flange portion 22 as a negative angle portion with respect to the acting direction of the impact load, the strength of the main body portion 2, particularly the bending strength, can be increased. As a result, the cross-sectional deformation of the main body portion 2 with respect to the impact load is suppressed.

Moreover, since the main body part 2 is heat-treated, the main body part 2 has high hardness. As the hardness is increased in this way, the strength of the main body portion 2 is also increased, and the cross-sectional deformation of the main body portion 2 with respect to the impact load is further suppressed.

Further, the pair of

terminal portions

3 and 4 of the vehicle impact beam 1 are not heat-treated. Here, when a member is heat-treated, the hardness of the member increases, while the toughness of the member decreases. Therefore, the hardness of the pair of

terminal portions

3 and 4 that are not heat-treated is low, but the toughness is high.

As described above, the pair of

terminal portions

3 and 4 are portions connected to the inner panel IP. When the toughness of the

terminal portions

3 and 4 having such a connection function is low, the

terminal portions

3 and 4 may be cracked by an impact load, and the vehicle impact beam 1 may be detached from the inner panel IP. When the vehicle impact beam 1 is detached from the inner panel IP, the vehicle impact beam 1 can no longer function as a reinforcing member. On the other hand, if the toughness of the

terminal portions

3 and 4 is high, the

terminal portions

3 and 4 may be deformed by an impact load, but the connection state with the inner panel IP is maintained thanks to the high toughness. As long as the connection state is maintained, the vehicle impact beam 1 can function as a reinforcing member. From the above, the characteristic required for the pair of

terminal portions

3 and 4 is high toughness rather than high hardness.

In this regard, according to the present embodiment, since the heat treatment is not performed on the pair of

terminal portions

3 and 4 as described above, the toughness is not reduced by the heat treatment. Therefore, as a result of the

terminal parts

3 and 4 exhibiting high toughness, the

terminal parts

3 and 4 can be prevented from cracking when an impact load is applied. As a result, the vehicle impact beam 1 can be effectively used as a reinforcing member. Can do.

Next, a method for manufacturing the vehicle impact beam 1 according to this embodiment will be described. In the present embodiment, the vehicle impact beam 1 is manufactured through a roll forming process, a partial heat treatment process, a cutting process, and a deformation process.

In the roll forming step, a roll-formed product having the same cross-sectional shape as the cross-sectional shape of the main body portion 2 of the vehicle impact beam 1 is produced by roll-forming a flat metal steel plate. That is, in the roll forming step, the projection is configured to be a long shape and projecting in a predetermined direction when viewed from the longitudinal direction, and in a direction approaching each other from both ends of the projection. A roll molded product having a pair of extended inner flange portions and having an open cross section is produced. This roll forming step is performed using a roll forming apparatus.

Also, in the partial heat treatment step, the roll-formed product is partially heat-treated along the longitudinal direction thereof, whereby the heat-treated heat-treated portion and the non-heat-treated non-heat-treated portion are alternately roll-formed along the longitudinal direction. Form into goods. In this embodiment, the heat processing apparatus for implementing this partial heat processing process is integrated in a roll forming apparatus.

FIG. 9 is a schematic side view of a roll forming apparatus incorporating a heat treatment apparatus. As shown in FIG. 9, the roll forming apparatus 50 according to this embodiment includes an uncoiler 51, a forming roll mold unit 52, a roll quench unit 53 as a heat treatment apparatus, and a cutting apparatus 54. These devices are aligned and arranged in the order described above along the pass line of the roll forming device 50. A steel strip H (metal steel plate) is fed from the uncoiler 51 side (upstream side) toward the cutting device 54 side (downstream side). Here, as shown in FIG. 9, the feeding direction of the steel strip H is defined as a direction from upstream to downstream.

The uncoiler 51 includes a coil part in which a steel strip H is wound in a coil shape and a rotating device that rotates the coil part. As the coil portion rotates, the steel strip H is pulled out at a constant speed.

The forming roll mold unit 52 includes a plurality of forming roll stands 521. The forming roll stand 521 includes an upper roll piece 522 and a lower roll piece 523 that are arranged side by side so that the rotation axes of the forming roll stand 521 are arranged in parallel with each other in the vertical direction, and the lower roll piece 523 rotates. The steel strip H is sent out. The upper roll piece 522 is rotated by a frictional force with the steel strip H to be sent out. For this reason, the upper roll piece 522 and the lower roll piece 523 rotate at the same speed in opposite directions.

The plurality of forming roll stands 521 are arranged in a straight line along the feeding direction of the steel strip H. The steel strip H sent out from the uncoiler 51 is introduced into the forming roll mold unit 52. The steel strip H is roll-formed by the forming roll die unit 52 so that the cross section has a desired shape, and then sent to the downstream side of the forming roll die unit 52.

The roll quench unit 53 is disposed on the downstream side of the forming roll mold unit 52. The roll quench unit 53 includes an induction heater 531 and a cooling water supply device 532 and is arranged in this order along the feeding direction of the steel strip H.

The induction heater 531 is disposed downstream of the forming roll mold unit 52 in the feed direction of the steel strip H. The induction heater 531 includes an induction heating coil 531a disposed so as to surround the outer periphery of the steel strip H that has passed through the forming roll stand 521 located on the most downstream side, and an energization control device that controls energization of the induction heating coil 531a. 531b. The energization controller 531b energizes the induction heating coil 531a, so that the steel strip H passing through the induction heating coil 531a is instantaneously heated.

The cooling water supply device 532 includes a cooling water supply source 532a, a supply pipe 532b connected to the cooling water supply source 532a, and a cooling water jet nozzle 532c attached to the tip of the supply pipe 532b. Cooling water from the cooling water supply source 532a is supplied to the cooling water ejection nozzle 532c through the supply pipe 532b. Then, cooling water is ejected from the cooling water ejection nozzle 532c. Cooling water ejected from the cooling water ejection nozzle 532 c is sprayed on the steel strip H that has passed through the induction heater 531.

A cutting device 54 is disposed downstream of the roll quench unit 53. The cutting device 54 cuts the steel strip H that has passed through the roll quench unit 53 into a desired length.

The operation of the roll forming apparatus 50 configured as described above will be described below. The steel strip H sent out from the uncoiler 51 is first fed into the forming roll mold unit 52. The steel strip H is plastically deformed each time it passes between the upper roll piece 522 and the lower roll piece 523 of the plurality of forming roll stands 521. Accordingly, the cross-sectional shape shown in FIG. 4, that is, the convex portion (main body-side convex portion 21) configured to protrude in a predetermined direction when viewed from the longitudinal direction, and both ends of the convex portion A roll molded product is formed such that the cross-sectional shape perpendicular to the longitudinal direction is an open cross-sectional shape (see FIG. 1). Process). In addition, although it is difficult to shape | mold the inner flange part (22,22) which is a negative angle part by normal press molding, such an inner flange part (22,22) can be shape | molded easily by roll forming.

The roll molded product that has passed through the molding roll die unit 52 is sent downstream from the molding roll die unit 52 and passes through the induction heating coil 531a. At this time, when the induction heating coil 531a is energized, the roll molded product passing through the induction heating coil 531a is heated. In the present embodiment, the heating temperature is adjusted so that the roll molded product is heated to a temperature equal to or higher than the austenitizing temperature. In addition, energization of the induction heating coil 531a is controlled by the energization control device 531b so that the roll molded product is partially heated along the longitudinal direction. Thereby, the heating part heated with the induction heating coil 531a and the non-heating part which is not heated are alternately formed along the longitudinal direction of a roll molded product. Here, the axial length of the heating portion is the same as the axial length of the main body portion 2 of the vehicle impact beam 1, and the axial length of the non-heating portion is the front end of the vehicle impact beam 1. The length is the same as the sum of the axial lengths of the portion 3 and the rear terminal portion 4.

The cooling water jetted from the cooling water jet nozzle 532c of the cooling water supply device 532 located downstream of the induction heating coil 531a is sprayed on the roll molded product that has passed through the induction heating coil 531a. Thereby, the heated portion is rapidly cooled to a temperature lower than the martensitic transformation point, for example, room temperature. The heated portion is heat-treated by this rapid cooling. On the other hand, the non-heated portion is not heat-treated. That is, along the longitudinal direction of the roll-formed product, heat-treated portions that have been heat-treated and non-heat-treated portions that have not been heat-treated are alternately formed on the roll-formed product (partial heat treatment step). Thereafter, the roll molded product is fed into the cutting device 54. The roll molded product is cut into a desired length by the cutting device 54 (cutting step). At this time, the non-heated part is cut. Therefore, a long roll molded product is formed in which both end portions are non-heat treated portions and a portion between both non-heat treated portions is a heat treated portion.

Next, a cut is formed at a boundary portion between the inner flange portion provided in the non-heat treated portion and the inner flange portion provided in the heat treated portion constituting both ends of the roll molded product cut to a desired length. Alternatively, unnecessary portions in the boundary portion are trimmed by a press notch or the like. Thereafter, the roll molded product is placed on a press molding machine. And the non-heat-treatment part of both ends is deformed with a press molding machine (deformation process). By this press molding, the cross-sectional shape of the non-heat treated portion of the roll molded product is deformed.

FIG. 10 is a diagram showing one mode of deformation of the cross-sectional shape of the non-heat treated portion of the roll molded product when the deformation process is performed. FIG. 10A is a cross-sectional view of the non-heat-treated portion before the deformation process, and FIG. 10B is a cross-sectional view of the non-heat-treated portion after the deformation process. As shown in FIG. 10 (a), the non-heat treated portion 6 before the deformation step is provided with a pair of protrusions 61 projecting in a predetermined direction and extending in a direction approaching each other from both ends of the protrusion 61.

Inner flange portions

62, 62 are formed. The cross-sectional shape shown in FIG. 10A is the same as the cross-sectional shape of the heat treatment portion, and is the same as the cross-sectional shape of the main body portion 2 of the vehicle impact beam 1.

The pair of

inner flange portions

62, 62 shown in FIG. 10 (a) are bent in the opening direction as shown by the arrow direction in FIG. 10 (a) in the deformation process. At this time, the base end portion following the inner flange portion 62 of the convex portion 61 may be bent and deformed together. That is, a portion of the convex portion 61 below the broken line L shown in FIG. 10A may be bent and deformed together with the inner flange portion 62. Due to this bending deformation, as shown in FIG. 10 (b), the non-heat-treated portion 7 after the deformation step is formed with a convex portion 71 protruding in the same direction as the protruding direction of the convex portion 61, and both sides of the convex portion 71. A pair of

outer flange portions

72, 72 extending in a direction away from the end are formed. Note that the cross-sectional shape after deformation shown in FIG. 10B is only an example. Actually, the cross-sectional shape of the non-heat-treated portion constituting one end of one roll molded product obtained by the cutting process is deformed so as to be the cross-sectional shape of the front terminal portion 3 shown in FIG. Is done. Moreover, the cross-sectional shape of the non-heat-treated part which comprises the other edge part of one roll molded product obtained by a cutting process is deform | transformed by the deformation | transformation process so that it may become the cross-sectional shape of the rear side terminal part 4 shown in FIG. The

In the roll molded product that has undergone the deformation process, a heat-treated portion having a cross-sectional shape shown in FIG. 10A and a non-heat-treated portion having a cross-sectional shape shown in FIG. Moreover, the heat treatment part is formed in a long shape, and non-heat treatment parts are connected to both ends in the longitudinal direction of the heat treatment part. The heat treatment portion constitutes the main body portion 2 of the vehicle impact beam 1, and the non-heat treatment portion connected to one end of the heat treatment portion in the longitudinal direction constitutes the front end portion 3 of the vehicle impact beam 1. The non-heat-treated portion connected to the other end of the heat-treated portion constitutes the rear end portion 4 of the vehicle impact beam 1. Thus, the vehicle impact beam 1 according to the present embodiment is manufactured.

As mentioned above, although embodiment of this invention was described, this invention should not be limited to the said embodiment. For example, the shape of the main body portion 2 is not limited to that shown in FIG. 4, and may be any shape as long as the main body side convex portion 21 and the pair of inner flange portions 22 are provided. Similarly, the pair of

terminal portions

3 and 4 may have any shape as long as the terminal-side

convex portions

31 and 41 and the pair of

outer flange portions

32 and 42 are provided. Moreover, the cross-sectional shape of the main-body part 2 and a pair of

terminal parts

3 and 4 may be formed so that it may change a little along a longitudinal direction. Moreover, the hollow part 211a provided in the main-body part 2 and the

hollow parts

311a and 411a provided in the

terminal parts

3 and 4 are not essential structures. Moreover, the length in the longitudinal direction of one outer flange part may differ from the length in the longitudinal direction of the other outer flange part among a pair of outer flange parts. In this case, a gradually deforming portion is interposed between the main body portion 2 and the

terminal portions

3 and 4. FIG. 11 is a DD cross section of FIG. 2 and shows a cross-sectional shape of the gradually deforming portion. As shown in FIG. 11, the gradually deformed portion J includes an inner flange portion F1 extending from the tip of one side wall portion S1 of the pair of side wall portions forming the convex portion P1, and the other side wall portion S2. The outer flange part F2 extended from the front-end | tip of this is provided. The

terminal portions

3 and 4 may be connected to both ends of the main body portion 2 through such a gradually deforming portion where the inner flange portion and the outer flange portion are formed. Moreover, in the said embodiment, although a deformation | transformation process is implemented after a cutting process, you may implement a cutting process after a deformation | transformation process. In this case, a press molding machine that is movable along the pass line direction may be provided on the pass line of the roll forming apparatus 50 and between the roll quench unit 53 and the cutting apparatus 54. By incorporating a press molding machine for carrying out the deformation process into the roll forming apparatus in this way, the installation space for the production facility can be reduced compared with the case where a press molding machine for the deformation process is provided separately from the roll forming apparatus. be able to. Further, the heat treatment apparatus is not incorporated in the roll forming apparatus, and may be provided separately from the roll forming apparatus. Thus, the present invention can be modified without departing from the gist thereof.

Claims

An impact beam for a vehicle, which is disposed inside a vehicle door and includes an elongated main body portion and a pair of terminal portions connected to both ends in the longitudinal direction of the main body portion,
The main body portion and the pair of terminal portions are integrally formed by deforming a metal steel plate,
The main body portion has a main body side convex portion protruding in a predetermined direction when viewed from the longitudinal direction and a pair of inner flange portions extending in a direction approaching each other from both side ends of the main body side convex portion, and The cross-sectional shape perpendicular to the longitudinal direction is an open cross-sectional shape,
The terminal portion is a pair of terminal-side convex portions projecting in the same direction as the projecting direction of the main-body-side convex portion when viewed from the longitudinal direction and a pair extending in a direction away from both side ends of the terminal-side convex portion. An impact beam for a vehicle having an outer flange portion and configured so that a cross-sectional shape perpendicular to the longitudinal direction is an open cross-sectional shape.
The impact beam for a vehicle according to claim 1,
The main body side convex portion extends in a direction facing each other from the main body side outer wall portion having a surface perpendicular to the protruding direction when viewed from the longitudinal direction of the main body portion and both side ends of the main body side outer wall portion. A pair of body side walls,
The pair of inner flange portions is a vehicle impact beam that extends in a direction approaching each other from the extended ends of the pair of main body side wall portions when viewed from the longitudinal direction of the main body portion.
The vehicle impact beam according to claim 2,
The terminal-side convex portion is extended in a direction facing each other from the terminal-side outer wall portion having a surface perpendicular to the protruding direction when viewed from the longitudinal direction of the main body portion and both end portions of the terminal-side outer wall portion. A pair of terminal side wall portions,
The pair of outer flange portions are vehicle impact beams that extend in directions away from the extended ends of the pair of terminal-side side wall portions when viewed from the longitudinal direction of the main body portion.
In the impact beam for vehicles according to any one of claims 1 to 3,
The main body is heat treated,
An impact beam for a vehicle, wherein the pair of terminal portions are not heat-treated.
The impact beam for a vehicle according to any one of claims 1 to 4,
The impact beam for vehicles attached to the said door for vehicles so that the protrusion direction of the said main body side convex part and the said terminal side convex part is the outward in a vehicle width direction.
A method of manufacturing an impact beam for a vehicle,
A pair of inner flanges extending in a direction approaching each other from both ends of the convex portions protruding in a predetermined direction when viewed from the longitudinal direction by roll forming a metal steel plate Roll forming step of producing a roll molded product having a section and a cross-sectional shape perpendicular to the longitudinal direction thereof is an open cross-sectional shape;
By heat-treating the roll-formed product partially along the longitudinal direction, heat-treated portions that have been heat-treated and non-heat-treated portions that have not been heat-treated alternate with the roll-formed product along the longitudinal direction. A partial heat treatment step to be formed into,
The non-heat-treated portion extends in a direction away from each other from a convex portion protruding in the same direction as the protruding direction of the convex portion formed in the heat-treated portion when viewed from the longitudinal direction and both side ends of the convex portion. A deforming step of deforming the non-heat-treated portion so that a cross-sectional shape perpendicular to the longitudinal direction is an open / close cross-sectional shape, and having a pair of outer flange portions provided;
The manufacturing method of the impact beam for vehicles containing this.
It is a manufacturing method of the impact beam for vehicles according to claim 6,
The deformation step is a step of forming the outer flange portion by deforming the inner flange portion formed in the non-heat treated portion by press-molding the non-heat treated portion. Production method.