Manufacturing method of press-molded products

Abstract

To preferably suppress generation of break or wrinkle in press-molding.SOLUTION: A manufacturing method of a press-molded article includes forming an intermediate molded article by press-molding, and forming a press-molded article by press-molding the intermediate molded article. The intermediate molded article has a top plate part, a pre-vertical wall part, a pre-lateral wall part, a pre-bottom wall part and a swollen part. The press-molded article has a top plate part, a vertical wall part, a lateral wall part, a bottom wall part, a first ridge line, a second ridge line, a third ridge line and an aggregate part. The swollen part is a plate-like part adjacent to the pre-vertical wall part, the pre-lateral wall part, and the pre-bottom wall part. The swollen part is deformed by press-molding so as to form the press-molded article from the intermediate molded article.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present disclosure relates to a method for producing a press-molded product by press molding. [Background technology]

[0002] As described in Patent Document 1, a technique is known for forming a groove-shaped member having a continuous flange portion by press molding. The continuous flange portion means a flange portion provided in a state where the end portion in the elongation direction and the end portion in the width direction of the groove-shaped member are connected. The continuous flange portion has a bent portion (hereinafter, a ridge line) formed at the boundary between the end portion in the elongation direction and the end portion in the width direction.

[0003] In the manufacturing method disclosed in Patent Document 1, when forming the above-mentioned member, first, an intermediate product provided with a continuous flange portion and a ridge line is formed from a blank material by press forming, and then, the intermediate product is press formed to form a groove-shaped member. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6265315 Summary of the Invention [Problem to be solved by the invention]

[0005] The technology disclosed in Patent Document 1 can suppress the occurrence of wrinkles around the ridge line of the continuous flange portion. However, the method of Patent Document 1 cannot sufficiently distribute the load applied to the intermediate molded product during press molding, which may cause cracks or wrinkles.

[0006] In one aspect of the present disclosure, it is desirable to suppress the occurrence of cracks or wrinkles during press molding. [Means for solving the problem]

[0007] One aspect of the present disclosure is a manufacturing method for a press-molded product, comprising: forming an intermediate product by press molding a plate-shaped member; and forming the press-molded product by press molding the intermediate product. The press-molded product comprises a top plate portion, a vertical wall portion, a horizontal wall portion, a bottom wall portion, a first ridge line, a second ridge line, a third ridge line, and a collection portion. The top plate portion is a plate-shaped portion having a vertical end portion and a horizontal end portion. The vertical wall portion is a plate-shaped portion extending from the vertical end portion of the top plate portion. The horizontal wall portion is a plate-shaped portion extending from the horizontal end portion of the top plate portion and adjacent to the vertical wall portion. The bottom wall portion is a plate-shaped portion adjacent to the vertical wall portion and the horizontal wall portion. The first ridge line forms a boundary between the vertical wall portion and the bottom wall portion. The second ridge line forms a boundary between the horizontal wall portion and the bottom wall portion. The third ridge line forms a boundary between the horizontal wall portion and the vertical wall portion. The gathering portion is a dot-like or planar portion connected to the respective ends of the first, second, and third ridge lines. The bottom wall portion protrudes from the first ridge line toward the bulging side, and the lateral wall portion protrudes from the third ridge line toward the bulging side. The intermediate molded product includes a top plate portion, a pre-vertical wall portion, a pre-lateral wall portion, a pre-bottom wall portion, and a bulging portion. The pre-vertical wall portion is a plate-like portion extending from a vertical end portion of the top plate portion. The pre-lateral wall portion is a plate-like portion extending from a lateral end portion of the top plate portion. The pre-bottom wall portion is a plate-like portion adjacent to the pre-vertical wall portion and the pre-lateral wall portion. The bulging portion is a plate-like portion adjacent to the pre-vertical wall portion, the pre-lateral wall portion, and the pre-bottom wall portion. The bulging portion is located on the bulging side of the first and third ridge lines, and intersects with a pre-second ridge line forming a boundary between the pre-lateral wall portion and the pre-bottom wall portion on the bulging side of the gathering portion. The bulge is deformed by press molding, so that a press-molded product is formed from the intermediate product.

[0008] According to the above-mentioned configuration, since the intermediate molded product has the bulge, it is possible to prevent load concentration during press molding, and therefore it is possible to prevent cracks or wrinkles from occurring during press molding.

[0009] In one aspect of the present disclosure, the apex may be a portion of the boundary between the bulging portion and the pre-lateral wall portion that is located closest to the top plate portion. The apex may be located in the vicinity of the top plate portion. According to the above-mentioned configuration, it is possible to further suppress the concentration of the load when the intermediate product is press-molded, and therefore it is possible to more suitably suppress the occurrence of cracks or wrinkles during press molding.

[0010] In one aspect of the present disclosure, the bulge portion may have a peak that is an end located opposite the pre-bottom wall portion. The peak may extend along an end of the top plate portion. According to the above-mentioned configuration, it is possible to further suppress the concentration of the load when the intermediate product is press-molded, and therefore it is possible to more suitably suppress the occurrence of cracks or wrinkles during press molding.

[0011] In one embodiment of the present disclosure, the press-molded product may be curved such that an end portion in the direction of the first ridge line protrudes toward the opposite side of the bottom wall portion. According to the above configuration, the occurrence of cracks or wrinkles can be suppressed when forming a press-molded product.

[0012] In one embodiment of the present disclosure, the press-formed product may be made of high-tensile steel having a tensile strength of 980 MPa or more. According to the above configuration, the occurrence of cracks or wrinkles can be suppressed when forming a press-molded product. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 is a perspective view of a press-formed product according to a first embodiment. [Diagram 2] FIG. 2 is a side view of the blank piece according to the first embodiment. [Diagram 3] FIG. 2 is a perspective view of an intermediate product in the manufacturing method of the press-formed product according to the first embodiment. [Figure 4] FIG. 11 is a perspective view of an intermediate product in a manufacturing method of a press-formed product according to a second embodiment. [Diagram 5] FIG. 13 is a perspective view of a collection portion of a modified example of the first and second embodiments. [Figure 6] 5 is an explanatory diagram of a bulging portion and a covering portion in the first embodiment. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, exemplary embodiments of the present disclosure will be described with reference to the drawings. [1. First embodiment] [(1) Press-molded products] The press-formed product 1 of the first embodiment is formed by press-forming a metal material (see FIG. 1). In the first embodiment, high-tensile steel having a tensile strength of 980 MPa or more is used as the metal material. However, the metal material is not limited thereto, and may be, for example, high-tensile steel having a tensile strength of 1470 MPa or more, high-tensile steel having a tensile strength of less than 980 MPa, stainless steel, or iron.

[0015] Moreover, the press-formed product 1 is used as a member constituting the body of a vehicle, for example. However, without being limited thereto, the press-formed product 1 may be used as a member constituting a part of a vehicle other than the body, or may be used as a member that is not mounted on a vehicle.

[0016] The press-formed product 1 is a plate-like member and includes a top plate portion 2, a vertical wall portion 3, a horizontal wall portion 4, a bottom wall portion 5, a first wall portion 12, and a second wall portion 13. In addition, as will be described in detail later, the press-formed product 1 has first to third ridge lines 61 to 63 that extend in different directions starting from a collection portion 60 which is a point-like portion. Hereinafter, the directions in which the first to third ridge lines 60 to 61 extend are referred to as first to third directions D1 to D3, respectively.

[0017] The press-molded product 1 is a groove-shaped member and extends from a first end 10 to a second end 11 along a first direction D1. The press-molded product 1 has a curved shape such that the first end 10 and the second end 11 protrude toward the opposite side of the bottom wall portion 5, in other words, the center in the first direction D1 protrudes toward the bottom wall portion 5. Of course, the press-molded product 1 is not limited to this, and may have a shape that extends straight.

[0018] [(2) Top panel] The top plate portion 2 is a plate-like portion extending from a first end 10 to a second end 11, and includes a vertical end portion 20, a horizontal end portion 21, a protruding portion 22, and an opposite end portion 23 (see FIG. 1). Similar to the press-molded product 1, the top plate portion 2 is curved so that both ends in the first direction D1 protrude toward the opposite side of the bottom wall portion 5.

[0019] The vertical end portion 20 is located at the end portion of the top plate portion 2 in the width direction (hereinafter also simply referred to as the width direction) of the press-molded product 1, and extends from near the first end 10 to the second end 11 along the first direction D1.

[0020] The protruding portion 22 is located near the first end 10 of the top plate portion 2, protruding from the end in the width direction along the second direction D2, and has, for example, a substantially triangular shape. The horizontal end portion 21 is an end portion of the protruding portion 22, and extends from the end portion of the vertical end portion 20 on the first end 10 side along the second direction D2.

[0021] The opposite end 23 is located on the opposite side of the top plate portion 2 from the protruding portion 22, and extends along the first direction D1 from the first end 10 to the second end 11. The opposite end 23 faces the vertical end 20 in the width direction.

[0022] [(3) First and second wall portions] The first wall portion 12 is a plate-like portion that protrudes from the opposite end portion 23 along the third direction D3 (see FIG. 1).

[0023] The second wall portion 13 is a plate-shaped portion protruding along the second direction D2 from an end portion opposite to the opposite end portion 23 of the first wall portion 12. The second wall portion 13 is formed as a flange-shaped portion, for example.

[0024] [(4) Vertical wall portion, horizontal wall portion, and bottom wall portion] The vertical wall portion 3 is a plate-shaped portion extending along the third direction D3 from the vertical end portion 20 of the top plate portion 2. The vertical wall portion 3 extends along the first direction D1 and faces the first wall portion 12 in the width direction (see FIG. 1).

[0025] The horizontal wall portion 4 is a plate-shaped portion extending from the horizontal end portion 21 of the top plate portion 2 along the third direction D3 and adjacent to the vertical wall portion 3. The horizontal wall portion 4 extends from the end portion of the vertical wall portion 3 on the first end 10 side along the second direction D2.

[0026] The bottom wall portion 5 is a plate-shaped portion adjacent to the vertical wall portion 3 and the horizontal wall portion 4. The bottom wall portion 5 extends along the first and second directions D1 and D2. The horizontal wall portion 4 and the bottom wall portion 5 each intersect with the vertical wall portion 3 at a predetermined angle, and are formed, for example, as elongated flange-like portions extending along the ends of the vertical wall portion 3. The horizontal wall portion 4 and the bottom wall portion 5 also intersect with each other at a predetermined angle. For example, these predetermined angles may be greater than or equal to 90° and less than or equal to 135°.

[0027] The boundary between the vertical wall portion 3 and the bottom wall portion 5 forms a first ridge line 61. The boundary between the horizontal wall portion 4 and the bottom wall portion 5 forms a second ridge line 62. The boundary between the horizontal wall portion 4 and the vertical wall portion 3 forms a third ridge line 63. As described above, the first to third ridge lines 61 to 63 extend in different directions starting from the gathering portion 60, and the gathering portion 60 is adjacent to the vertical wall portion 3, the horizontal wall portion 4, and the bottom wall portion 5. The bottom wall portion 5 extends from the first ridge line 61 to a bulging side, which will be described later, and the horizontal wall portion 4 also extends from the third ridge line 63 to the bulging side.

[0028] [(5) Method for manufacturing press-molded products] The method for manufacturing the press-molded product 1 includes a first step and a second step. In the first step, a plate-shaped blank B (see FIG. 2) made of the above-mentioned metal material is press-molded using a die (not shown) to form an intermediate product 1A. As an example, the blank B has a curved shape. However, the present invention is not limited to this, and the blank B may be flat.

[0029] In the first step, the intermediate product 1A may be formed not only from the blank material B but also from a plate-like member that has been processed into a predetermined shape by press molding or the like. In the second step, the intermediate product 1A is press-molded using a die (not shown) to form the press-molded product 1. Specifically, a bulging portion 7 (described later) in the intermediate product 1A is deformed to form the press-molded product 1 from the intermediate product 1A. More specifically, the bulging portion 7 is pressed toward the assembly portion 60 to form the press-molded product 1. Note that in the second step, in addition to the bulging portion 7, a portion of the intermediate product 1A other than the bulging portion 7 may be deformed.

[0030] [(6) Intermediate molded product] The intermediate product 1A has a similar shape to the press-formed product 1, but differs from the press-formed product 1 in that a bulge 7 is formed in the area surrounding the assembly portion 60 in the press-formed product 1 (see FIG. 3). The intermediate product 1A includes a first wall portion 12, a second wall portion 13, a top plate portion 2, a pre-vertical wall portion 3A, a pre-horizontal wall portion 4A, a pre-bottom wall portion 5A, and the bulge 7.

[0031] The first wall portion 12, the second wall portion 13, and the top plate portion 2 of the intermediate molded product 1A have the same configurations as the first wall portion 12, the second wall portion 13, and the top plate portion 2 of the press-molded product 1, respectively. In addition, the pre-vertical wall portion 3A, the pre-horizontal wall portion 4A, and the pre-bottom wall portion 5A of the intermediate molded product 1A correspond to the vertical wall portion 3, the horizontal wall portion 4, and the bottom wall portion 5 of the press-molded product 1, respectively. However, since the intermediate molded product 1A has a bulge portion 7, the pre-vertical wall portion 3A, the pre-horizontal wall portion 4A, and the pre-bottom wall portion 5A of the intermediate molded product 1A have differences from the vertical wall portion 3, the horizontal wall portion 4, and the bottom wall portion 5 of the press-molded product 1, respectively.

[0032] That is, the pre-vertical wall portion 3A, like the vertical wall portion 3, is a plate-shaped portion extending from the vertical end portion 20 of the top plate portion 2 along the third direction D3, extends along the first direction D1, and faces the first wall portion 12 in the width direction.

[0033] Similar to the side wall portion 4, the pre-side wall portion 4A is a plate-shaped portion extending from the side end portion 21 of the top plate portion 2 along the third direction D3. The pre-bottom wall portion 5A, like the bottom wall portion 5, is a plate-shaped portion adjacent to the pre-vertical wall portion 3A and the pre-horizontal wall portion 4A, and extends along the first and second directions D1 and D2.

[0034] The pre-horizontal wall portion 4A and the pre-bottom wall portion 5A intersect with the pre-vertical wall portion 3A and the bulging portion 7 at a predetermined angle, and are formed as flange-shaped portions at the ends of the pre-vertical wall portion 3A and the bulging portion 7, for example. The pre-horizontal wall portion 4A and the pre-bottom wall portion 5A intersect with each other at a predetermined angle. As with the press-molded product 1, these predetermined angles may be, for example, 90° or more and 135° or less.

[0035] However, the pre-vertical wall portion 3A and the pre-horizontal wall portion 4A are not adjacent to each other, and a bulge portion 7, which is a plate-shaped portion, is provided between the pre-vertical wall portion 3A and the pre-horizontal wall portion 4A. In this respect, the intermediate product 1A differs from the press-formed product 1.

[0036] [(7) Bulge] The bulging portion 7 has a shape in which the portions of the vertical wall portion 3, the horizontal wall portion 4, and the bottom wall portion 5 of the press-formed product 1 around the assembly portion 60 bulge toward the bulging side described above (see FIG. 3).

[0037] The bulging portion 7 is located between the pre-vertical wall portion 3A and the pre-horizontal wall portion 4A, and is adjacent to these portions as well as to a portion around the end portion on the first end 10 side of the pre-bottom wall portion 5A. The bulging portion 7 is located on the bulging side of the first and third ridge lines 61, 63 and the gathering portion 60 of the press-formed product 1. The bulging portion 7 also intersects with the pre-second ridge line 62A on the bulging side of the gathering portion 60 of the press-formed product 1. The pre-second ridge line 62A is a portion that forms the boundary between the pre-horizontal wall portion 4A and the pre-bottom wall portion 5A. The boundary between the bulging portion 7 and the pre-horizontal wall portion 4A is located on the bulging side of the third ridge line 63 of the press-formed product 1, and the boundary between the bulging portion 7 and the pre-bottom wall portion 5A is located on the bulging side of the first ridge line 61 of the press-formed product 1. Further, on the second end 11 side of the bulging portion 7, a pre-first ridge line 61A is formed which forms the boundary between the pre-vertical wall portion 3A and the pre-bottom wall portion 5A.

[0038] The bulging portion 7 has a planar shape as an example, but is not limited thereto, and may have a curved shape as an example. Moreover, the bulging portion 7 has a substantially rectangular shape as viewed from the front as an example. Here, the part of the boundary between the bulging portion 7 and the pre-horizontal wall portion 4A that is located closest to the top plate portion 2 is defined as the vertex 71. The vertex 71 is located in the vicinity of the top plate portion 2. Specifically, the vertex 71 is located on the vertical end portion 20 of the top plate portion 2, but is not limited to this, and the vertex 71 may be located a small distance away from the vertical end portion 20.

[0039] In addition, an end portion (hereinafter, referred to as a vertex portion 70) forming the side opposite to the pre-bottom wall portion 5A in the bulging portion 7 extends along the vertical end portion 20 of the top plate portion 2. Specifically, the vertex portion 70 is located on the vertical end portion 20, but is not limited thereto, and there may be a slight distance between the vertex portion 70 and the vertical end portion 20.

[0040] In addition, a gap may be provided between the apex portion 70 and the vertical end portion 20. Specifically, for example, the apex portion 70 may be provided around the pre-bottom wall portion 5A. In other words, the pre-vertical wall portion 3A and the pre-horizontal wall portion 4A may be adjacent to each other on the top plate portion 2 side of the bulging portion 7.

[0041] [2. Second embodiment] The method for manufacturing the press-molded product 1 in the second embodiment differs from that in the first embodiment in the shape of the bulge 7 in the intermediate product 1A (see FIG. 4). The following describes the differences between the intermediate product 1A in the second embodiment and the first embodiment.

[0042] In the second embodiment, the bulging portion 7 has a shape in which the portions around the gathering portion 60 in the vertical wall portion 3, the horizontal wall portion 4, and the bottom wall portion 5 of the press-formed product 1 are bulged toward the bulging side, as in the first embodiment. That is, the bulging portion 7 is located on the bulging side of the first and third ridge lines 61, 63 and the gathering portion 60 in the press-formed product 1, as in the first embodiment. The bulging portion 7 also intersects with the pre-second ridge line 62A on the bulging side of the gathering portion 60 of the press-formed product 1. The boundary between the bulging portion 7 and the pre-horizontal wall portion 4A is located on the bulging side of the third ridge line 63 of the press-formed product 1, and the boundary between the bulging portion 7 and the pre-bottom wall portion 5A is located on the bulging side of the first ridge line 61 of the press-formed product 1.

[0043] However, in the second embodiment, the bulge portion 7 is, for example, an approximately triangular portion when viewed from the front, and, similar to the first embodiment, is adjacent to the pre-vertical wall portion 3A and the pre-horizontal wall portion 4A, as well as adjacent to the peripheral portion of the end portion on the first end 10 side of the pre-bottom wall portion 5A.

[0044] In the second embodiment, the pre-vertical wall portion 3A and the pre-horizontal wall portion 4A are adjacent to each other on the top plate portion 2 side of the bulging portion 7, and a pre-third ridge line 63A forming the boundary between these portions extends from the boundary between the vertical end portion 20 and the horizontal end portion 21 toward the pre-bottom wall portion 5A. The portion forming the apex of the bulging portion 7 (hereinafter, apex 71), in other words, the portion of the boundary between the bulging portion 7 and the pre-horizontal wall portion 4A that is located closest to the top plate portion 2, is located at the end of the pre-third ridge line 63A.

[0045] As an example, the vertex 71 is located in the vicinity of the assembly portion 60 in the press-formed product 1, in other words, in the vicinity of the pre-bottom wall portion 5A. However, the position of the vertex 71 is determined appropriately, and the vertex 71 may be located, for example, in the vicinity of the top plate portion 2, that is, on the vertical end portion 20 or at a position slightly away from the vertical end portion 20.

[0046] [3. Modifications] In the first and second embodiments, the gathering portion 60 of the press-molded product 1 is configured as a dot-like portion. However, the gathering portion 60 may be a portion that spreads out in a planar shape and be located on the bulging side of the intersections (hereinafter, virtual intersections) of the virtual lines extending from the first to third ridgelines 61 to 63. In other words, the gathering portion 60 may have a shape similar to that obtained by chamfering the dot-like gathering portion 60 in the first and second embodiments.

[0047] As an example, the assembly portion 60 has a shape similar to that obtained by chamfering the intersections of the first to third ridges 61 to 63, and is formed as a substantially triangular planar portion (see FIG. 5). The ends of the first to third ridges 61 to 63 are connected to the vertices of the assembly portion 60, and the portions forming the sides of the assembly portion 60 are adjacent to the vertical wall portion 3, the horizontal wall portion 4, and the bottom wall portion 5.

[0048] Alternatively, the gathering portion 60 may have a shape similar to that obtained by chamfering the intersections of the first to third ridgelines 61 to 63, and may be formed as a curved planar portion.

[0049] Then, in the second step, when the press-molded product 1 is formed from the intermediate product 1A in the same manner as in the first and second embodiments, the bulging portion 7 of the intermediate product 1A is pressed to form the gathering portion 60. For this reason, the gathering portion 60 is smaller than the bulging portion 7 and is located closer to the virtual intersection point of the first to third ridgelines 61-63 than the bulging portion 7.

[0050] [4. Effects] (1) When the press-formed product 1 is formed from the blank B by one press forming, there is a possibility that cracks may occur in the peripheral portion of the gathering portion 60 (hereinafter, the gathering portion peripheral portion 64), and wrinkles may occur in the peripheral portion of the end portion opposite the gathering portion 60 at the second ridge line 62 (hereinafter, the outer end portion 65) (see FIG. 1). The reason is that the gathering portion peripheral portion 64 of the press-formed product 1 is a portion where three faces gather, and further, the inclination between each face is steep. For this reason, during press forming, the movement of the material is likely to be restricted in the gathering portion peripheral portion 64, and the vicinity of the gathering portion 60 becomes a contact point, and the load is likely to be concentrated on the gathering portion peripheral portion 64. Note that the contact point is a portion to which a relatively high load is applied during press forming, and the portion that contacts the die in the initial stage of press forming may become the contact point.

[0051] Here, in order to suppress cracks at the assembly peripheral portion 64 of the press-formed product 1, it is conceivable to reduce the load applied to the assembly peripheral portion 64 during press forming. However, this does not reduce the plate thickness of the assembly peripheral portion 64, and as a result, the material accumulated at the outer end portion 65 becomes less likely to move to the assembly peripheral portion 64, and there is a concern that wrinkles may easily occur at the outer end portion 65.

[0052] In contrast, in the manufacturing method of the above embodiment, the intermediate product 1A has a bulge 7 formed around the position where the assembly peripheral portion 64 in the press-formed product 1 is formed, and the bulge 7 reduces the inclination of the intersecting surfaces. As a result, in the press forming of the first step, the position of the blank B corresponding to the bottom point 72 of the intermediate product 1A becomes the abutment point. The bottom point 72 means the intersection point between the bulge 7 and the pre-first ridge line 61A. As a result, in the blank B during the press forming of the first step, the position of the abutment point is easily changed, and excessive load concentration on the portion around the bottom point 72 can be suppressed, and the plate thickness of that portion can be appropriately reduced.

[0053] In addition, in the press molding of the second step, a contact point is generated at the planar bulging portion 7 of the intermediate molded product 1A, so that it is possible to promote a change in the position of the contact point, and it is possible to suppress concentration of the load. In addition, since the plate thickness is reduced in the peripheral portion of the bottom point 72 of the intermediate molded product 1A, it is possible to promote the movement of material from the outer end portion 65 to the portion. In addition, the area of ​​the bulging portion 7 is smaller than the area of ​​the plate-shaped portion (hereinafter, the covering portion 66) surrounded by the line corresponding to the outer edge 73 of the bulging portion 7 in the press molded product 1 (see FIG. 6). In other words, during the press molding of the second step, the covering portion 66 is formed by the deformation of the bulging portion 7, but since the area of ​​the covering portion 66 is larger than the area of ​​the bulging portion 7, the plate thickness of the covering portion 66 is thinner than the plate thickness of the bulging portion 7. Therefore, it is possible to promote the movement of material from the outer end portion 65 to the covering portion 66.

[0054] This makes it possible to suppress within an allowable range a decrease in thickness in the peripheral portion of the position corresponding to the bottom point 72 and in the convergence portion peripheral portion 64, and an increase in thickness at the outer end portion 65 in the press-formed product 1. As a result, it is possible to suppress cracks in the convergence portion peripheral portion 64 and wrinkles at the outer end portion 65 in the press-formed product 1.

[0055] (2) In the first embodiment, the apex 71 of the bulge 7 is located near the top plate 2, and the top portion 70 of the bulge 7 extends along the vertical end portion 20. Therefore, in the press molding in the second step, the abutment point in the bulge 7 of the intermediate molded product 1A can be moved farther away from the position corresponding to the assembly portion 60. This further promotes the change in the position of the abutment point, and more suitably suppresses the concentration of the load. In addition, since the area of ​​the bulge 7 can be sufficiently secured, the difference between the area of ​​the bulge 7 and the area of ​​the covering portion 66 becomes large. Therefore, in the press molding in the second step, the movement of the material from the outer end portion 65 to the covering portion 66 can be promoted. Therefore, in the press molding in the second step, the cracks in the assembly portion periphery 64 and the wrinkles in the outer end portion 65 in the press molded product 1 can be more suitably suppressed.

[0056] (3) Furthermore, since the press-molded product 1 in the above embodiment has a curved shape, when the press-molded product 1 is formed from the blank B by one press molding, a load is likely to concentrate on the peripheral portion 64 of the gathering portion, which results in cracks in the peripheral portion 64 of the gathering portion and wrinkles in the outer end portion 65. In contrast, by providing the first step of forming the intermediate molded product 1A having the bulge portion 7 as in the above embodiment, cracks in the peripheral portion 64 of the gathering portion and wrinkles in the outer end portion 65 of the press-molded product 1 can be effectively suppressed.

[0057] (4) Furthermore, the press-formed product 1 of the above embodiment is made of high-tensile steel with a tensile strength of 980 MPa or more. This makes it easy for cracks to occur in the assembly portion peripheral portion 64 and wrinkles to occur in the outer end portion 65. In contrast, by providing the first step of forming the intermediate product 1A having the bulge portion 7 as in the above embodiment, it is possible to effectively suppress cracks in the assembly portion peripheral portion 64 and wrinkles in the outer end portion 65 of the press-formed product 1.

[0058] 5. Other embodiments (1) In the above embodiment, the horizontal wall portion 4 and the bottom wall portion 5 in the press-molded product 1 are configured as elongated flange-like portions extending along the ends of the vertical wall portion 3. However, the horizontal wall portion 4 and the bottom wall portion 5 may be portions that extend in a planar shape from the ends of the vertical wall portion 3 instead of being flange-like portions.

[0059] (2) Multiple functions possessed by one component in the above embodiments may be realized by multiple components, or one function possessed by one component may be realized by multiple components. Also, multiple functions possessed by multiple components may be realized by one component, or one function realized by multiple components may be realized by one component. Also, part of the configuration of the above embodiments may be omitted. Also, at least part of the configuration of the above embodiments may be added to or substituted for the configuration of another of the above embodiments.

[0060] [6. Technical Concepts Disclosed in This Specification] [Item 1] A method for manufacturing a press-molded product, comprising the steps of: forming an intermediate product by press molding a plate-shaped member; forming a press-molded product by press molding the intermediate molded product; The press-molded product is A top plate portion which is a plate-shaped portion having vertical ends and horizontal ends; A vertical wall portion which is a plate-shaped portion extending from the vertical end portion of the top plate portion; A horizontal wall portion that is a plate-shaped portion extending from the horizontal end portion of the top plate portion and adjacent to the vertical wall portion; A bottom wall portion which is a plate-shaped portion adjacent to the vertical wall portion and the horizontal wall portion; a first edge line that forms a boundary between the vertical wall portion and the bottom wall portion; a second ridge line that forms a boundary between the side wall portion and the bottom wall portion; a third ridge line forming a boundary between the horizontal wall portion and the vertical wall portion; a collection portion which is a point-like or planar portion connected to each end of the first, second, and third ridge lines, the bottom wall portion protrudes from the first ridge line toward the bulging side, and the lateral wall portion protrudes from the third ridge line toward the bulging side, The intermediate molded product is The top plate portion, A pre-vertical wall portion which is a plate-shaped portion extending from the vertical end portion of the top plate portion; A pre-side wall portion which is a plate-shaped portion extending from the side end portion of the top plate portion; A pre-bottom wall portion which is a plate-shaped portion adjacent to the pre-vertical wall portion and the pre-horizontal wall portion; The pre-vertical wall portion, the pre-horizontal wall portion, and a bulge portion which is a plate-shaped portion adjacent to the pre-bottom wall portion, The bulging portion is located on the bulging side of the first and third ridge lines, and intersects with a pre-second ridge line that forms a boundary between the pre-side wall portion and the pre-bottom wall portion on the bulging side of the collection portion, The bulge is deformed by press molding to form the press-molded product from the intermediate product. A manufacturing method for press-molded products.

[0061] [Item 2] A method for producing a press-molded product according to item 1, In the bulging portion, a portion of the boundary with the pre-side wall portion that is located closest to the top plate portion is defined as a vertex, The apex is located near the top plate portion. A manufacturing method for press-molded products.

[0062] [Item 3] A method for producing a press-molded product according to item 1 or 2, The bulge portion has a top portion which is an end portion located opposite to the pre-bottom wall portion, The top portion extends along the edge of the top plate portion. A manufacturing method for press-molded products.

[0063] [Item 4] A method for producing a press-molded product according to any one of items 1 to 3, The press-formed product is curved such that an end portion in the direction of the first ridge line protrudes toward the opposite side of the bottom wall portion. A manufacturing method for press-molded products.

[0064] [Item 5] A method for producing a press-molded product according to any one of items 1 to 4, The press-formed product is made of high-tensile steel having a tensile strength of 980 MPa or more. A manufacturing method for press-molded products. [Explanation of symbols]

[0065] 1...press-formed product, 1A...intermediate formed product, 2...top plate portion, 20...vertical end portion, 21...horizontal end portion, 3...vertical wall portion, 3A...pre-vertical wall portion, 4...horizontal wall portion, 4A...pre-horizontal wall portion, 5...bottom wall portion, 5A...pre-bottom wall portion, 60...assembly portion, 61...first ridge line, 61A...pre-first ridge line, 62...second ridge line, 62A...pre-second ridge line, 63...third ridge line, 63A...pre-third ridge line, 64...periphery of assembly portion, 65...outer end portion, 66...covering portion, 7...bulge portion, 70...top portion, 71...vertex, 72...bottom point, B...blank material, D1...first direction, D2...second direction, D3...third direction.

Claims

1. A method for manufacturing a press-molded product, comprising the steps of: A first step of forming an intermediate product by press molding a plate-shaped member; A second step of forming a press-molded product by press molding the intermediate molded product, The press-molded product is A top plate portion which is a plate-shaped portion having vertical ends and horizontal ends; A vertical wall portion which is a plate-shaped portion extending from the vertical end portion of the top plate portion; A horizontal wall portion that is a plate-shaped portion extending from the horizontal end portion of the top plate portion and adjacent to the vertical wall portion; A bottom wall portion which is a plate-shaped portion adjacent to the vertical wall portion and the horizontal wall portion; a first ridge line that forms a boundary between the vertical wall portion and the bottom wall portion; a second ridge line that forms a boundary between the side wall portion and the bottom wall portion; a third ridge line forming a boundary between the horizontal wall portion and the vertical wall portion; a collection portion which is a point-like or planar portion connected to each end of the first, second, and third ridge lines, the bottom wall portion protrudes from the first ridge line toward the bulging side, and the lateral wall portion protrudes from the third ridge line toward the bulging side, The intermediate molded product is The top plate portion, A pre-vertical wall portion which is a plate-shaped portion extending from the vertical end portion of the top plate portion and which becomes the vertical wall portion by the second process; A pre-side wall portion which is a plate-shaped portion extending from the side end portion of the top plate portion and which becomes the side wall portion by the second process; A pre-bottom wall portion which is a plate-shaped portion adjacent to the pre-vertical wall portion and the pre-horizontal wall portion and which becomes the bottom wall portion by the second step; A pre-second ridge line that forms a boundary between the pre-side wall portion and the pre-bottom wall portion; The pre-vertical wall portion, the pre-horizontal wall portion, and a bulge portion which is a plate-shaped portion adjacent to the pre-bottom wall portion, The pre-vertical wall portion, the pre-horizontal wall portion, and the pre-bottom wall portion differ from the vertical wall portion, the horizontal wall portion, and the bottom wall portion in that the bulge portion is provided, respectively; The bulging portion is located on the bulging side of positions corresponding to the first and third ridge lines in the intermediate molded product, and intersects with the pre-second ridge line on the bulging side of a position corresponding to the gathering portion in the intermediate molded product, In the second step, the bulge portion is deformed by press molding, whereby the vertical wall portion, the horizontal wall portion, and the bottom wall portion are formed from the pre-vertical wall portion, the pre-horizontal wall portion, and the pre-bottom wall portion, thereby forming the press-molded product from the intermediate molded product. A manufacturing method for press-molded products.

2. A method for producing a press-molded product according to claim 1, In the bulging portion, a portion of the boundary with the pre-side wall portion that is located closest to the top plate portion is defined as a vertex, The apex is located near the top plate portion. A manufacturing method for press-molded products.

3. A method for producing a press-molded product according to claim 1 or 2, The bulge portion has a top portion which is an end portion located opposite to the pre-bottom wall portion, The top portion extends along the edge of the top plate portion. A manufacturing method for press-molded products.

4. A method for producing a press-molded product according to claim 1 or 2, The press-formed product is curved such that an end portion in the direction of the first ridge line protrudes toward the opposite side of the bottom wall portion. A manufacturing method for press-molded products.

5. A method for producing a press-molded product according to claim 1 or 2, The press-formed product is made of high-tensile steel having a tensile strength of 980 MPa or more. A manufacturing method for press-molded products.

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