Manufacturing method of press formed product

Abstract

To provide a manufacturing method of a press formed product which suppresses wrinkle from occurring at the time of press forming.SOLUTION: A manufacturing method of a press formed product comprises the steps of: press-forming a first formed part from blank; press-forming a second formed part from the first formed part; and press-forming a press formed product from the second formed part. The press formed product extending in a longer direction includes: a top plate part; and a vertical wall part. The first formed part includes: a preliminary top plate part; a surface-skived part; and a flat part. The second includes: a preliminary top plate part; a surface-skived part; and a preliminary vertical wall part. The preliminary vertical wall part is, while holding by metal mold the preliminary top plate of the first formed part and the surface-skived part thereof, formed by deforming the flat part.SELECTED DRAWING: Figure 8

Description

[Technical Field]

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

[0002] As described in Patent Document 1, a technology is known for forming a component by press molding that has a plate-shaped top plate portion extending in the longitudinal direction and a plate-shaped vertical wall portion protruding from the widthwise end of the top plate.

[0003] In the manufacturing method disclosed in Patent Document 1, when forming the above-mentioned member, the portion of the workpiece corresponding to the top plate portion is sandwiched between a first mold and a second mold, and then a third mold disposed adjacent to the first mold is moved relative to the first and second molds to form the vertical wall portion. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2021-194687 Summary of the Invention [Problem to be solved by the invention]

[0005] According to the technology disclosed in Patent Document 1, the component is formed with the top plate portion sandwiched between the first and second molds, which makes it possible to prevent wrinkles from occurring in the top plate portion during press molding. However, with the method of Patent Document 1, sufficient pressure cannot be applied to the vertical wall portion during press molding, which may result in wrinkles occurring in the vertical wall portion.

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

[0007] One aspect of the present disclosure is a method for manufacturing a press-formed product, comprising: forming a first formed product by press-forming a plate-shaped blank; forming a second formed product by press-forming the first formed product; and forming a press-formed product by press-forming the second formed product. The press-formed product is a member extending in the longitudinal direction. The method for manufacturing a press-formed product further comprises a top plate portion and a vertical wall portion. The top plate portion is an elongated plate-shaped portion extending in the longitudinal direction. The vertical wall portion is a wall-shaped portion protruding from both ends of the top plate portion in the width direction to a first side. The first formed product is a member extending in the longitudinal direction. The method for manufacturing a press-formed product further comprises a preliminary top plate portion, a face-cut portion, and a flat portion. The preliminary top plate portion is an elongated plate-shaped portion extending in the longitudinal direction. The face-cut portion is a plate-shaped portion extending from a first end of the preliminary top plate portion in the width direction so as to bend toward the first side. The flat portion is a plate-shaped portion extending from the end of the face scraped portion opposite the preliminary top plate portion. The second molded product is a member extending in the longitudinal direction. The manufacturing method for a press-molded product further includes a preliminary top plate portion, a face scraped portion, and a preliminary vertical wall portion. The preliminary vertical wall portion is a wall-shaped portion protruding toward the first side from the end of the face scraped portion opposite the preliminary top plate portion. The preliminary vertical wall portion is formed by deforming the flat portion while the preliminary top plate portion and the face scraped portion of the first molded product are clamped between molds.

[0008] According to the above configuration, when the preliminary vertical wall portion is formed, the preliminary top plate portion and the chamfered portion of the first molded product are clamped by the mold, which makes it possible to prevent wrinkles from occurring during press molding. In one embodiment of the present disclosure, the first molded product may be formed by clamping a blank between a first mold disposed on a first side and a second mold disposed on a second side opposite the first side. The preliminary vertical wall portion may be formed by pressing the flat portion from the second side with a third mold disposed on the second side while the preliminary top plate portion and the face scraping portion of the first molded product are clamped between the first mold and the second mold.

[0009] According to the above configuration, the preliminary top plate portion, the chamfered portion, and the preliminary vertical wall portion can be suitably formed. In one embodiment of the present disclosure, the press-molded product may be formed by clamping the preliminary top plate portion of the second molded product between a fourth mold arranged on a second side opposite the first side and a fifth mold arranged on the first side, and pressing and deforming the surface trimming portion with a sixth mold arranged on the first side.

[0010] According to the above configuration, the top plate portion and the vertical wall portion can be formed suitably. In one embodiment of the present disclosure, when the press-molded product is formed by press-molding the second molded product, the face scraping portion and the preliminary vertical wall portion may abut against the fourth mold and the sixth mold.

[0011] According to the above configuration, the vertical wall portion can be suitably formed. In one embodiment of the present disclosure, the second molded product may include a flange portion, which is a plate-shaped portion that protrudes from an end of the preliminary vertical wall portion opposite the face scraping portion. The flange portion of the second molded product may correspond to a part of the flat portion of the first molded product. When forming a press-molded product by press molding the second molded product, the flange portion of the second molded product may abut against a fourth mold and a sixth mold.

[0012] According to the above configuration, the flange portion can be formed suitably. In one embodiment of the present disclosure, press molding for forming the first molded product, the second molded product, and the press-molded product may be performed by displacing a mold along a first direction. The press-molded product may include a first top plate end portion located in the width direction of the top plate portion and corresponding to a part of the surface scraping portion of the second molded product. In a first cross section of the second molded product perpendicular to the longitudinal direction, the distance in the first direction between the end portion of the auxiliary top plate portion on the surface scraping portion side and the end portion of the auxiliary vertical wall portion opposite the surface scraping portion may be substantially the same as the distance in the first direction between the first top plate end portion and the end portion of the vertical wall portion protruding from the first top plate end portion in a cross section of the press-molded product perpendicular to the longitudinal direction corresponding to the first cross section.

[0013] According to the above configuration, the top plate portion and the vertical wall portion can be formed suitably. In one embodiment of the present disclosure, both longitudinal ends of the top plate portion may be located on a second side opposite the first side. The top plate portion may include a curved portion that is a portion curved so as to bulge toward the first side in a cross section along the longitudinal direction. The second molded product may include a chamfered portion in a portion of the press-molded product corresponding to the curved portion.

[0014] According to the above configuration, it is possible to prevent wrinkles from occurring in the curved portion during press forming. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. [Figure 2] FIG. 2 is a side view showing an end portion in the width direction of the press-formed product. [Figure 3] FIG. [Figure 4] FIG. 2 is a side view showing a longitudinal end portion of the press-formed product. [Figure 5] FIG. 10 is an explanatory diagram showing the state at the start of the first step. [Figure 6] FIG. 10 is an explanatory diagram showing the state at the completion of the first step. [Figure 7] FIG. 10 is an explanatory view showing a state during press forming in a second step. [Figure 8] FIG. 10 is an explanatory diagram showing the state at the completion of the second step. [Figure 9] FIG. 10 is an explanatory diagram showing the state at the start of the third step. [Figure 10] FIG. 10 is an explanatory diagram showing the state at the completion of the third step. DETAILED DESCRIPTION OF THE INVENTION

[0016] Hereinafter, exemplary embodiments of the present disclosure will be described with reference to the drawings. [1. First embodiment] [1-1. 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 to this, 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.

[0017] Moreover, the press-formed product 1 is used as a member that constitutes the body of a vehicle, for example, but is not limited thereto, and the press-formed product 1 may be used as a member that constitutes a part other than the body of the vehicle, or may be used as a member that is not mounted on the vehicle.

[0018] The press-molded product 1 is a plate-shaped member and includes a top plate portion 12, a vertical wall portion 13, a flange portion 14, an opposite vertical wall portion 15, and an opposite flange portion 16 (see FIGS. 1 to 4). The press-formed product 1 is a groove-shaped member that extends from a first end 10 to a second end 11 along the longitudinal direction. The press-formed product 1 has a curved shape such that the first end 10 and the second end 11 protrude toward a second side D2, i.e., in a cross section along the longitudinal direction, the press-formed product 1 bulges toward the first side D1 near the center (see FIG. 2). The first side D1 is the side on which the flange portion 14 and the opposite flange portion 16 are located with respect to the top plate portion 12, and the second side D2 is the opposite side of the first side D1. Of course, the press-formed product 1 is not limited to this, and may have a shape that extends straight in a cross section along the longitudinal direction.

[0019] The top plate portion 12 is a long, narrow plate-like portion extending in the longitudinal direction from the first end 10 to the second end 11. From near the center of the longitudinal direction of the top plate portion 12 to the second end 11, the length in the width direction (hereinafter also simply referred to as the width direction) of the press-molded product 1 increases as it moves from the first end 10 to the second end 11. The top plate portion 12 has a curved portion 120.

[0020] The curved portion 120 is a plate-shaped portion located in a curved portion that bulges out toward the first side D1 in a cross section along the longitudinal direction of the top panel portion 12. The curved portion 120 is located approximately in the center of the top panel portion 12 in the longitudinal direction.

[0021] The vertical wall portion 13 is a plate-shaped portion that protrudes from the widthwise end of the top plate portion 12 to the first side D1, extends from the first end 10 to the second end 11 of the top plate portion 12, and comprises an upper vertical wall portion 130, a first step portion 131, a second step portion 132, and a lower vertical wall portion 133.

[0022] The upper vertical wall portion 130 is a wall-shaped portion that protrudes from the end portion in the width direction of the top panel portion 12 toward the first side D1. The first step portion 131 and the second step portion 132 are located at the end of the upper vertical wall portion 130 opposite the top plate portion 12, and are stepped portions that protrude to the opposite side of the opposite vertical wall portion 15. The first step portion 131 and the second step portion 132 are aligned along the longitudinal direction, with the first step portion 131 located on the first end 10 side and the second step portion 132 located on the second end 11 side. When viewed from the second side D2, the first step portion 131 has a substantially triangular shape (see FIG. 3). An end portion that forms one side of the first step portion 131 extends along the end portion of the upper vertical wall portion 130. The vertical wall portion 13 does not necessarily have to include the first step portion 131 and the second step portion 132. In other words, the vertical wall portion 13 may be, for example, a wall-like portion that protrudes straight from the end portion in the width direction of the top panel portion 12 toward the first side D1 without bending.

[0023] The lower vertical wall portion 133 is a wall-shaped portion that protrudes from the end portion of the first step portion 131 and the second step portion 132 opposite to the opposite vertical wall portion 15 toward the first side D1. The flange portion 14 is a plate-shaped portion that protrudes from the end of the lower vertical wall portion 133 opposite the first step portion 131 and the second step portion 132 to the side opposite the opposite vertical wall portion 15.

[0024] The opposite side vertical wall portion 15 is a plate-shaped portion that protrudes toward the first side D1 from the end of the top plate portion 12 opposite to the vertical wall portion 13. The opposite side vertical wall portion 15 faces the vertical wall portion 13 in the width direction. Note that the opposite side vertical wall portion 15 may have a stepped portion like the first stepped portion 131 and the second stepped portion 132 of the vertical wall portion 13. In addition, in a cross section perpendicular to the longitudinal direction of the press-molded product 1, the length by which the opposite vertical wall portion 15 protrudes to the first side D1 is preferably equal to or less than the length by which the vertical wall portion 13 protrudes to the first side D1, and more preferably equal to or less than the length by which the vertical wall portion 13 protrudes to the first side D1.

[0025] The opposite flange portion 16 is a plate-shaped portion that protrudes from the end of the opposite vertical wall portion 15 opposite the top plate portion 12 to the opposite side of the vertical wall portion 13. [1-2. Manufacturing methods for press-molded products] The manufacturing method of the press-formed product 1 includes a first step, a second step, and a third step. In the first step, a first press-formed product 5 is formed by press-forming a blank B (see FIGS. 5 and 6). In the second step, a second press-formed product 6 is formed by press-forming the first press-formed product 5 (see FIGS. 7 and 8). In the third step, a press-formed product 1 is formed by press-forming the second press-formed product 6 (see FIGS. 9 and 10).

[0026] [1-3. Press molding equipment in the first process] In the first step, a plate-shaped blank B made of the above-mentioned metal material and extending in the longitudinal direction is press-formed using a press-forming device to form a first formed product 5 (see FIG. 5).

[0027] The press molding device in the first step includes a first lower die 2, an upper pad 3, and a first upper die 4, which are dies for press molding. The first lower die 2 is located below the blank B. The first lower die 2 has a shape that extends along the longitudinal direction and has a shape that protrudes upward in a cross section (hereinafter simply referred to as a cross section) perpendicular to the longitudinal direction. The first lower die 2 includes a preliminary top plate forming section 20, a chamfer forming section 21, a preliminary vertical wall forming section 22, a flange forming section 23, an opposite vertical wall forming section 24, and an opposite flange forming section 25.

[0028] The preliminary top plate forming portion 20 is a molding surface that extends along the longitudinal direction and forms the upper surface of the portion of the first lower mold 2 that protrudes upward. The chamfer forming portion 21 is a forming surface that extends from one end of the preliminary top plate forming portion 20 in the width direction so as to curve downward.

[0029] The preliminary vertical wall forming portion 22 is a forming surface that extends downward from the end of the face scraping forming portion 21 opposite to the preliminary top plate forming portion 20. The preliminary vertical wall forming portion 22 has a smaller angle with respect to the up-down direction than the face scraping forming portion 21. The flange forming portion 23 is a forming surface that extends from the end of the preliminary vertical wall forming portion 22 opposite to the chamfer forming portion 21 to the opposite side to the opposite vertical wall forming portion 24 .

[0030] The opposite vertical wall forming portion 24 is a forming surface that extends downward from the end portion of the preliminary top plate forming portion 20 opposite to the chamfer forming portion 21. The opposite flange forming portion 25 is a forming surface that extends from the end of the opposite vertical wall forming portion 24 opposite to the preliminary top plate forming portion 20 to the opposite side to the flange forming portion 23. The opposite flange forming portion 25 is located above the flange forming portion 23.

[0031] The upper pad 3 has a shape that extends along the longitudinal direction and is located above the blank B. The upper pad 3 is supported from above by a gas spring and is displaceable in the vertical direction. The upper pad 3 is arranged facing the first lower die 2 in the vertical direction. The upper pad 3 includes a preliminary top plate forming section 30 and a face scraping forming section 31.

[0032] The preliminary top plate forming portion 30 is a long and narrow forming surface that extends along the longitudinal direction of the upper pad 3. The preliminary top plate forming portion 30 faces the preliminary top plate forming portion 20 of the first lower mold 2 in the up-down direction. The chamfer forming portion 31 is a forming surface that extends so as to curve downward from the widthwise end of the preliminary top plate forming portion 30 on the side of the preliminary vertical wall forming portion 22 of the first lower mold 2. The chamfer forming portion 31 faces the chamfer forming portion 21 of the first lower mold 2 in the up-down direction.

[0033] The first upper die 4 is a die for press molding. The first upper die 4 has a shape extending along the longitudinal direction and is located above the blank B. The first upper die 4 is disposed facing the first lower die 2 in the vertical direction and is movable in the vertical direction. The first upper die 4 includes a preliminary vertical wall forming portion 40, a flange forming portion 41, an opposite vertical wall forming portion 42, and an opposite flange forming portion 43.

[0034] The preliminary vertical wall forming portion 40 is a molding surface that extends upward from the widthwise end of the flange forming portion 41 on the upper pad 3 side. The preliminary vertical wall forming portion 40 faces the preliminary vertical wall forming portion 22 of the first lower mold 2 in the up-down direction.

[0035] The flange forming portion 41 is a molding surface located in the lower portion of the first upper die 4. The flange forming portion 41 is located on the side of the chamfer forming portion 31 in the width direction of the upper pad 3, and faces the flange forming portion 23 of the first lower die 2 in the up-down direction.

[0036] The opposite side vertical wall forming portion 42 is a molding surface that extends upward from the widthwise end of the opposite side flange forming portion 43 on the upper pad 3 side. The opposite side vertical wall forming portion 42 faces the opposite side vertical wall forming portion 24 of the first lower mold 2 in the up-down direction.

[0037] The opposite flange forming portion 43 is a molding surface located in the lower portion of the first upper mold 4. The opposite flange forming portion 43 is located on the preliminary top plate forming portion 30 side in the width direction of the upper pad 3, and faces the opposite flange forming portion 25 of the first lower mold 2 in the up-down direction.

[0038] [1-4. 1st step] In the first step, the blank material B is placed between the first lower mold 2 and the upper pad 3 (see FIG. 5). Then, the upper pad 3 is displaced downward to sandwich the blank material B between the first lower mold 2 and the upper pad 3 (see FIG. 6).

[0039] At this time, the upper surface of the blank material B abuts against the preliminary top plate forming portion 30 and the chamfer forming portion 31 of the upper pad 3, and the lower surface of the blank material B abuts against the preliminary top plate forming portion 20 and the chamfer forming portion 21 of the first lower mold 2. Furthermore, by receiving pressure from the first lower mold 2 and the upper pad 3, the blank material B deforms along the preliminary top plate forming portion 30 and the chamfer forming portion 31. As a result, the preliminary top plate forming portion 30 and the chamfer forming portion 31 are formed from the blank material B.

[0040] Through the above steps, the first molded product 5 is formed from the blank B. [1-5. 1st molded product] The first molded product 5 is a plate-like member extending in the longitudinal direction, and includes a preliminary top plate portion 50, a face-scraped portion 51, a flat portion 52, and an opposite-side flat portion 53 (see FIG. 6).

[0041] The auxiliary top plate portion 50 is a long, thin plate-like portion extending along the longitudinal direction. The face scraping portion 51 is a plate-shaped portion that extends from one end of the auxiliary top plate portion 50 in the width direction so as to curve downward (in other words, toward the first side D1).

[0042] The flat portion 52 is a plate-shaped portion that extends from the end of the face-scraped portion 51 on the side opposite to the auxiliary top plate portion 50 . The opposite flat portion 53 is a plate-like portion that extends from the end of the spare top plate portion 50 opposite to the face-scraped portion 51 .

[0043] [1-6. 2nd process] In the second step, the first molded product 5 formed in the first step is clamped between the first lower mold 2 and the upper pad 3, and the first upper mold 4 is displaced downward to press the flat portion 52 and the opposite flat portion 53 (see Figure 7).

[0044] When the first upper mold 4 is displaced downward, the upper surface of the flat portion 52 abuts against the preliminary vertical wall forming portion 40 and flange forming portion 41 of the first upper mold 4, and the lower surface of the flat portion 52 abuts against the preliminary vertical wall forming portion 22 and flange forming portion 23 of the first lower mold 2.

[0045] Furthermore, the flat portion 52 is deformed along the preliminary vertical wall forming portion 40 and the flange forming portion 41 by receiving pressure from the first lower mold 2 and the first upper mold 4. As a result, a preliminary vertical wall portion 62 and a flange portion 63 are formed from the flat portion 52 (see FIG. 8).

[0046] Furthermore, when the first upper mold 4 is displaced downward, the upper surface of the opposite side flat portion 53 abuts against the opposite side vertical wall forming portion 42 and the opposite side flange forming portion 43 of the first upper mold 4, and the lower surface of the opposite side flat portion 53 abuts against the opposite side vertical wall forming portion 24 and the opposite side flange forming portion 25 of the first lower mold 2.

[0047] Furthermore, the opposite-side flat portion 53 is deformed along the opposite-side vertical wall forming portion 42 and the opposite-side flange forming portion 43 by receiving pressure from the first lower mold 2 and the first upper mold 4. As a result, the opposite-side vertical wall portion 64 and the opposite-side flange portion 65 are formed from the opposite-side flat portion 53.

[0048] Through the above steps, the second molded product 6 is formed from the first molded product 5. [1-7.Second molded product] The second molded product 6 is a plate-shaped member extending along the longitudinal direction, and includes a preliminary top plate portion 60, a face-cut portion 61, a preliminary vertical wall portion 62, a flange portion 63, an opposite vertical wall portion 64, and an opposite flange portion 65 (see Figure 8).

[0049] The auxiliary top plate portion 60 is a long, thin plate-like portion extending in the longitudinal direction. The face scraping portion 61 is a plate-shaped portion that extends and curves downward from one end in the width direction of the preliminary top plate portion 60. In the second step, the angle of the face scraping portion 61 with respect to the up-and-down direction of press molding may be, for example, 40° or more and less than 90°.

[0050] The preliminary vertical wall portion 62 is a plate-shaped portion that protrudes downward from the end of the face-cut portion 61 opposite to the preliminary top plate portion 60. The flange portion 63 is a plate-shaped portion that protrudes from the end of the preliminary vertical wall portion 62 opposite the chamfered portion 61 to the opposite side of the opposite vertical wall portion 64 .

[0051] The opposite vertical wall portion 64 is a plate-shaped portion that protrudes downward from the end portion of the auxiliary top plate portion 60 opposite to the face scraping portion 61. The opposite vertical wall portion 64 faces the auxiliary vertical wall portion 62 in the width direction.

[0052] The opposite flange portion 65 is a plate-shaped portion that protrudes from the end of the opposite vertical wall portion 64 on the opposite side to the auxiliary top plate portion 60 toward the opposite side to the auxiliary vertical wall portion 62. The auxiliary top plate portion 60 and the surface cut portion 61 in the second molded product 6 correspond to the auxiliary top plate portion 50 and the surface cut portion 51 in the first molded product 5. In addition, the opposite side vertical wall portion 64 and the opposite side flange portion 65 correspond to the opposite side vertical wall portion 15 and the opposite side flange portion 16 in the press-molded product 1.

[0053] [1-8. Press forming equipment in the third process] In the third step, the second molded product 6 is press-molded using a press molding device, thereby forming the press-molded product 1.

[0054] The press molding device in the third step includes a second upper die 7, a lower pad 8, and a second lower die 9, which are dies for press molding (see FIG. 9). The second upper die 7 is located above the second molded product 6 and is vertically displaceable. The second upper die 7 extends longitudinally and has a cross-sectional shape with its lower surface concave upward. The second upper die 7 includes a top plate forming portion 70, a vertical wall forming portion 71, a flange abutting portion 72, an opposite vertical wall abutting portion 73, and an opposite flange abutting portion 74.

[0055] The top plate forming portion 70 extends along the longitudinal direction and is a molding surface that forms the bottom surface of the portion where the lower surface of the second upper mold 7 is recessed upward. The vertical wall forming portion 71 is a forming surface that extends downward from one end of the top plate forming portion 70 in the width direction.

[0056] The flange abutting portion 72 is a forming surface that extends from the end of the vertical wall forming portion 71 opposite to the top plate forming portion 70 to the opposite side to the opposite vertical wall abutting portion 73. The opposite vertical wall abutting portion 73 is a forming surface that extends downward from the end of the top plate forming portion 70 on the opposite side to the vertical wall forming portion 71.

[0057] The opposite flange abutment portion 74 is a molding surface that extends from the end of the opposite vertical wall abutment portion 73 opposite to the top plate forming portion 70 to the opposite side to the vertical wall forming portion 71. The opposite flange abutment portion 74 is located above the flange abutment portion 72.

[0058] The lower pad 8 has a shape that extends along the longitudinal direction and has a cross-sectional shape with the upper surface protruding upward. The lower pad 8 is supported from below by a gas spring and is displaceable in the vertical direction. The lower pad 8 is located below the second molded product 6 and is arranged facing the second upper mold 7. The lower pad 8 has a spare top plate abutting portion 80, an opposite vertical wall abutting portion 81, and an opposite flange abutting portion 82.

[0059] The preliminary top plate abutting portion 80 is a molding surface that extends along the longitudinal direction and forms the upper surface of the portion that protrudes upward from the lower pad 8. The preliminary top plate abutting portion 80 faces the top plate forming portion 70 of the second upper mold 7 in the vertical direction.

[0060] The opposite-side vertical wall abutting portion 81 is a molding surface that extends downward from the widthwise end of the preliminary top plate abutting portion 80 on the opposite side from the second lower mold 9. The opposite-side vertical wall abutting portion 81 faces the opposite-side vertical wall abutting portion 73 of the second upper mold 7 in the up-down direction.

[0061] The opposite flange abutment portion 82 is a molding surface that extends from the end of the opposite vertical wall abutment portion 81 opposite to the spare top plate abutment portion 80 to the opposite side of the second lower mold 9. The opposite flange abutment portion 82 faces the opposite flange abutment portion 74 of the second upper mold 7 in the up-down direction.

[0062] The second lower die 9 has a shape extending in the longitudinal direction and a cross-sectional shape with an upper surface that protrudes upward. The second lower die 9 is located below the second molded product 6 and is arranged facing the second upper die 7. The second lower die 9 includes a top plate forming portion 90, a vertical wall forming portion 91, and a flange abutting portion 92.

[0063] The top plate forming portion 90 is a molding surface that extends along the longitudinal direction and forms the upper surface of the portion that protrudes upward of the second lower mold 9. The top plate forming portion 90 faces the top plate forming portion 70 of the second upper mold 7 in the vertical direction.

[0064] The vertical wall forming portion 91 is a molding surface that extends downward from the end of the top plate forming portion 90 that is located opposite the lower pad 8. The vertical wall forming portion 91 faces the vertical wall forming portion 71 of the second upper mold 7 in the up-down direction.

[0065] The flange abutment portion 92 is a molding surface that extends from the end of the vertical wall forming portion 91 opposite the top plate forming portion 90 to the opposite side of the lower pad 8. The flange abutment portion 92 faces the flange abutment portion 72 of the second upper mold 7 in the vertical direction.

[0066] [1-9. 3rd step] In the third step, the second molded product 6 is placed between the second upper mold 7 and the lower pad 8. Then, the second molded product 6 is sandwiched and held between the second upper mold 7 and the lower pad 8 (see FIG. 9).

[0067] At this time, the auxiliary top plate portion 60 of the second molded product 6 abuts against the top plate forming portion 70 of the second upper die 7 and the auxiliary top plate abutting portion 80 of the lower pad 8, and the opposite side vertical wall portion 64 abuts against the opposite side vertical wall abutting portion 73 of the second upper die 7 and the opposite side vertical wall abutting portion 81 of the lower pad 8. The opposite side flange portion 65 abuts against the opposite side flange abutting portion 74 of the second upper die 7 and the opposite side flange abutting portion 82 of the lower pad 8. In addition, the upper surface of the auxiliary vertical wall portion 62 abuts against the vertical wall forming portion 71 of the second upper die 7, and the upper surface of the flange portion 63 abuts against the flange abutting portion 72 of the second upper die 7. Meanwhile, gaps are generated between the surface scraping portion 61 and the top plate forming portion 70 and the vertical wall forming portion 71.

[0068] Then, the second molded product 6 is displaced downward while being sandwiched between the second upper die 7 and the lower pad 8, so that the face scraping portion 61 is pressed by the second lower die 9 (see FIG. 10). When the face scraping portion 61 is pressed by the second lower die 9, the upper surface of the face scraping portion 61 abuts against the top plate forming portion 70 and the vertical wall forming portion 71 of the second upper die 7, and the lower surface of the face scraping portion 61 abuts against the top plate forming portion 90 and the vertical wall forming portion 91 of the second lower die 9. In addition, the upper surface of the preliminary vertical wall portion 62 abuts against the vertical wall forming portion 71, and the lower surface abuts against the vertical wall forming portion 91, and the upper surface of the flange portion 63 abuts against the flange abutting portion 72, and the lower surface abuts against the flange abutting portion 92.

[0069] Then, the face scraping portion 61 is subjected to pressure from the second upper mold 7 and the second lower mold 9, and is deformed along the top plate forming portion 70 and the vertical wall forming portion 71. As a result of this deformation, material flows from the flange portion 63 into the preliminary vertical wall portion 62.

[0070] As a result, the top plate portion 12 and the vertical wall portion 13 are formed from the preliminary top plate portion 60, the chamfered portion 61 and the preliminary vertical wall portion 62. Through the above steps, the press-formed product 1 is formed from the second molded product 6.

[0071] The first distance is the vertical distance between the end of the auxiliary top plate portion 60 on the side of the face scraped portion 61 and the end of the auxiliary vertical wall portion 62 on the opposite side from the face scraped portion 61 in the first cross section of the second molded product 6. The second distance is the vertical distance between the end of the top plate portion 12 on the side of the vertical wall portion 13 (in other words, the end of the first top plate) and the end of the vertical wall portion 13 on the side of the flange portion 14 in the cross section corresponding to the first cross section of the press-molded product 1. The cross section corresponding to the first cross section of the press-molded product 1 is a cross section that is located at the same position in the longitudinal direction as the first cross section of the second molded product 6.

[0072] In this case, the first distance and the second distance are generally the same regardless of the position in the entire longitudinal direction where the first cross section is taken. In other words, when the press-formed product 1 is formed from the second product 6 in the third step, the vertical height does not generally change. [1-10.Effects] According to the first embodiment described above in detail, the following effects can be obtained.

[0073] (1) When forming the press-formed product 1 from the blank material B in a single press forming operation, it is conceivable to perform press forming while clamping the top plate portion 12 between dies to suppress the flow of material in the top plate portion 12 and prevent cracks and wrinkles from occurring, thereby forming the vertical wall portion 13. However, this makes it impossible to apply sufficient pressure to the vertical wall portion 13, which may cause wrinkles to occur in the vertical wall portion 13. In particular, wrinkles may occur in the portion of the vertical wall portion 13 near the top plate portion 12.

[0074] In contrast, in the manufacturing method of the above embodiment, in the second step, the preliminary top plate portion 50 and the surface scraping portion 51 of the first molded product 5 are clamped between the upper pad 3 and the first lower mold 2, and the flat portion 52 is deformed to form the preliminary vertical wall portion 62.

[0075] Therefore, during the press molding in the second step, the flow of material in the preliminary top plate portion 50 and the scraped surface portion 51 can be suppressed, and the occurrence of wrinkles in the preliminary top plate portion 50 and the scraped surface portion 51 of the second molded product 6 can be suppressed.

[0076] (2) Furthermore, when forming the press-molded product 1 from the blank material B by a single press molding, the vertical wall portion 13, which is tall in the vertical direction, is formed by a single press molding, so that the amount of material that flows during press molding is large, and there is a risk of wrinkles occurring in the vertical wall portion 13.

[0077] In contrast, in the manufacturing method of the above embodiment, the vertical height of the preliminary vertical wall portion 62 of the second molded product 6 formed in the second step is lower than that of the vertical wall portion 13, so the amount of material that flows during one press molding is reduced.

[0078] Therefore, it is possible to prevent wrinkles from occurring in the preliminary vertical wall portion 62 of the second molded product 6 during the press molding in the second step. (3) In the manufacturing method of the above embodiment, in the first step, the blank B is sandwiched between the first lower die 2 and the upper pad 3 to form the first molded product 5. Thereafter, while the first molded product 5 is still sandwiched between the first lower die 2 and the upper pad 3, the flat portion 52 is pressed by the first upper die 4 to form the second molded product 6.

[0079] According to this configuration, the preliminary top plate portion 60, the chamfered portion 61, and the preliminary vertical wall portion 62 of the second molded product 6 can be suitably formed. (4) In the manufacturing method of the above embodiment, in the third step, the preliminary top plate portion 60, the opposite side vertical wall portion 64, and the opposite side flange portion 65 of the second molded product 6 are clamped between the second upper die 7 and the lower pad 8. Then, with the second molded product 6 clamped, the second lower die 9 presses and deforms the chamfered portion 61, thereby forming the press-molded product 1.

[0080] Therefore, during the third press molding step, the flow of material in the auxiliary top plate portion 60, opposite side vertical wall portion 64 and opposite side flange portion 65 of the second molded product 6 is suppressed, and wrinkles can be suppressed from occurring in the top plate portion 12, opposite side vertical wall portion 15 and opposite side flange portion 16 of the press molded product 1.

[0081] (5) Furthermore, in the manufacturing method of the above embodiment, during press molding in the third step, the surface scraping portion 61, the preliminary vertical wall portion 62 and the flange portion 63 of the second molded product 6 are in contact with the second upper mold 7 and the second lower mold 9.

[0082] According to this configuration, excessive flow of the material during press-molding in the third step can be suppressed, and the occurrence of wrinkles in the press-molded product 1 can be suppressed. (6) In the manufacturing method of the above embodiment, the cut surface portion 61 of the second molded product 6 has ridges extending along the longitudinal direction at both ends in the width direction, thereby increasing the rigidity of the area around the cut surface portion 61 of the second molded product 6.

[0083] Therefore, during press forming in the third step, buckling around the chamfered portion 61 can be suppressed, and wrinkles can be suppressed from occurring in the press-formed product 1. (7) Furthermore, the press-formed product 1 of the above embodiment has a curved shape in a cross section along the longitudinal direction. Therefore, when the press-formed product 1 is formed from the blank B by a single press forming, the material tends to flow into the portion of the vertical wall portion 13 near the curved portion 120 during press forming, which tends to cause wrinkles.

[0084] In contrast to this, in the manufacturing method of the above embodiment, the second product 6 has a chamfered portion 61 at a portion corresponding to the curved portion 120 of the press-formed product 1. Therefore, the occurrence of wrinkles in the area near the curved portion 120 of the vertical wall portion 13 in the press-formed product 1 can be suppressed.

[0085] [1-11. Correspondence of Wording] In the above embodiment, the first lower mold 2 corresponds to an example of a first mold, the upper pad 3 corresponds to an example of a second mold, the first upper mold 4 corresponds to an example of a third mold, the second upper mold 7 corresponds to an example of a fourth mold, the lower pad 8 corresponds to an example of a fifth mold, and the second lower mold 9 corresponds to an example of a sixth mold.

[0086] 2. Other Embodiments (1) In the above embodiment, the second molded product 6 has the chamfered portion 61 over the entire length in the longitudinal direction. However, the second molded product 6 is not limited to this, and may have the chamfered portion 61 only in a portion in the longitudinal direction. For example, the second molded product 6 may have the chamfered portion 61 only in a portion corresponding to the curved portion 120 in the press-molded product 1. In the above embodiment, the second molded product 6 includes a chamfered portion 61 at one end in the width direction of the auxiliary top plate portion 60. However, the second molded product 6 is not limited to this, and may include a chamfered portion 61 at both ends in the width direction of the auxiliary top plate portion 60.

[0087] (2) In the above embodiment, the face scraped portion 61 of the second molded product 6 is a portion having a shape that extends straight in cross section. However, the face scraped portion 61 is not limited to this. For example, the face scraped portion 61 may have a bent shape in cross section, or may have a shape that extends while gently curving.

[0088] (3) In the above embodiment, each mold used in each process is formed as a single unit. However, each mold is not limited to this, and may be composed of multiple molds. For example, the upper pad 3 may be composed of a mold including a preliminary top plate forming portion 30 and a mold including a chamfer forming portion 31.

[0089] (4) In the above embodiment, the first, second, and third steps are performed consecutively in the manufacturing method of the press-formed product 1, and no other processing is performed between the steps. However, the manufacturing method of the press-formed product 1 is not limited to this process, and other processing may be performed between the steps.

[0090] (5) Multiple functions of one component in the above embodiments may be realized by multiple components, or one function of one component may be realized by multiple components. Also, multiple functions of 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.

[0091] [3. Technical Ideas Disclosed in the Present Specification] [Item 1] A method for manufacturing a press-molded product, forming a first formed product by press forming a plate-shaped blank material; forming a second molded product by press molding the first molded product; and forming the press-formed product by press forming the second molded product, The press-formed product is a member extending in a longitudinal direction, a top plate portion that is a long, narrow plate-shaped portion extending in the longitudinal direction; and vertical wall portions that are wall-shaped portions that protrude from both ends of the top panel portion in the width direction toward the first side, The first molded product is a member extending in the longitudinal direction, a spare top plate portion that is a long, narrow plate-shaped portion extending in the longitudinal direction; a chamfered portion that is a plate-shaped portion extending from a first end in the width direction of the auxiliary top plate portion so as to bend toward the first side; a flat portion that is a plate-shaped portion extending from an end of the surface scraping portion opposite to the auxiliary top plate portion; The second molded product is a member extending in the longitudinal direction, The spare top plate portion; The chamfering unit; a spare vertical wall portion that is a wall-shaped portion that protrudes from an end of the face scraping portion opposite to the spare top plate portion toward the first side, The preliminary vertical wall portion is formed by deforming the flat portion while the preliminary top plate portion and the chamfered portion of the first molded product are clamped by a mold. Manufacturing method for press-molded products.

[0092] [Item 2] A method for producing a press-molded product according to item 1, the first molded product is formed by clamping the blank between a first mold disposed on the first side and a second mold disposed on a second side opposite to the first side, The preliminary vertical wall portion is formed by pressing the flat portion from the second side with a third mold disposed on the second side while the preliminary top plate portion and the face scraping portion of the first molded product are sandwiched between the first mold and the second mold. Manufacturing method for press-molded products.

[0093] [Item 3] A method for producing a press-molded product according to item 1 or 2, The press-molded product is formed by sandwiching the preliminary top plate portion of the second molded product between a fourth mold disposed on a second side opposite to the first side and a fifth mold disposed on the first side, and pressing and deforming the chamfered portion with a sixth mold disposed on the first side. Manufacturing method for press-molded products.

[0094] [Item 4] Item 3. A method for producing a press-molded product according to item 3, When the press-molded product is formed by press molding the second molded product, the chamfered portion and the preliminary vertical wall portion abut against the fourth mold and the sixth mold. Manufacturing method for press-molded products.

[0095] [Item 5] Item 4. A method for producing a press-molded product according to item 4, the second molded product includes a flange portion, which is a plate-shaped portion, protruding from an end portion of the preliminary vertical wall portion opposite the face scraping portion, the flange portion of the second molded product corresponds to a part of the flat portion of the first molded product, When forming the press-molded product by press molding the second molded product, the flange portion of the second molded product abuts against the fourth mold and the sixth mold. Manufacturing method for press-molded products.

[0096] [Item 6] A method for producing a press-molded product according to any one of items 1 to 5, press molding for molding the first molded product, the second molded product, and the press-molded product is performed by displacing a mold along a first direction; The press-formed product includes a first top plate end portion that is an end portion located in the width direction of the top plate portion and corresponds to a part of the chamfered portion in the second molded product, In a first cross section of the second molded product perpendicular to the longitudinal direction, the distance in the first direction between the end of the preliminary top plate portion on the side of the surface scraping portion and the end of the preliminary vertical wall portion opposite the surface scraping portion is approximately the same as the distance in the first direction between the end of the first top plate and the end of the vertical wall portion protruding from the end of the first top plate in a cross section of the press-molded product perpendicular to the longitudinal direction corresponding to the first cross section. Manufacturing method for press-molded products.

[0097] [Item 7] A method for producing a press-molded product according to any one of items 1 to 6, both ends of the top plate portion in the longitudinal direction are located on a second side opposite to the first side, the top plate portion includes a curved portion that is a portion curved so as to bulge toward the first side in a cross section along the longitudinal direction, The second molded product has the chamfered portion at a portion corresponding to the curved portion in the press-molded product. Manufacturing method for press-molded products. [Explanation of symbols]

[0098] 1...press-molded product, 12...top plate portion, 13...vertical wall portion, 15...opposite side vertical wall portion, 2...first lower die, 3...upper pad, 4...first upper die, 5...first molded product, 50...spare top plate portion, 51...face scraping portion, 52...flat portion, 6...second molded product, 60...spare top plate portion, 61...face scraping portion, 62...spare vertical wall portion, B...blank material, D1...first side, D2...second side.

Claims

1. A method for manufacturing a press-molded product, forming a first formed product by press forming a plate-shaped blank material; forming a second molded product by press molding the first molded product; and forming the press-formed product by press-forming the second molded product, The press-formed product is a member extending in a longitudinal direction, a top plate portion that is a long, narrow plate-shaped portion extending in the longitudinal direction; vertical wall portions that are wall-shaped portions protruding from both ends of the top plate portion in the width direction toward the first side, The first molded product is a member extending in the longitudinal direction, a spare top plate portion that is a long, narrow plate-shaped portion extending in the longitudinal direction; a chamfered portion that is a plate-shaped portion extending from a first end portion in a width direction of the auxiliary top plate portion so as to bend toward the first side; a flat portion that is a plate-shaped portion extending from an end of the surface scraping portion opposite to the auxiliary top plate portion; The second molded product is a member extending in the longitudinal direction, The spare top plate portion; The chamfering unit; a preliminary vertical wall portion that is a wall-shaped portion that protrudes from an end of the surface trimming portion opposite to the preliminary top plate portion toward the first side, The preliminary vertical wall portion is formed by deforming the flat portion while the preliminary top plate portion and the chamfered portion of the first molded product are sandwiched between dies. Manufacturing method for press-molded products.

2. A method for manufacturing a press-molded product according to claim 1, the first molded product is formed by clamping the blank between a first mold disposed on the first side and a second mold disposed on a second side opposite to the first side, The preliminary vertical wall portion is formed by pressing the flat portion from the second side with a third mold disposed on the second side while the preliminary top plate portion and the surface scraping portion of the first molded product are sandwiched between the first mold and the second mold. Manufacturing method for press-molded products.

3. A method for manufacturing a press-molded product according to claim 1, The press-molded product is formed by sandwiching the preliminary top plate portion of the second molded product between a fourth mold disposed on a second side opposite to the first side and a fifth mold disposed on the first side, and pressing and deforming the chamfered portion with a sixth mold disposed on the first side. Manufacturing method for press-molded products.

4. The method for manufacturing a press-molded product according to claim 3, When the press-molded product is formed by press molding the second molded product, the chamfered portion and the preliminary vertical wall portion abut against the fourth mold and the sixth mold. Manufacturing method for press-molded products.

5. The method for manufacturing a press-molded product according to claim 4, the second molded product includes a flange portion, which is a plate-shaped portion, protruding from an end portion of the preliminary vertical wall portion opposite to the face scraping portion, the flange portion of the second molded product corresponds to a part of the flat portion of the first molded product, When forming the press-molded product by press molding the second molded product, the flange portion of the second molded product abuts against the fourth mold and the sixth mold. Manufacturing method for press-molded products.

6. A method for manufacturing a press-molded product according to claim 1, press molding for molding the first molded product, the second molded product, and the press-molded product is performed by displacing a mold along a first direction; The press-formed product includes a first top plate end portion that is an end portion located in the width direction of the top plate portion and corresponds to a part of the chamfered portion in the second molded product, In a first cross section of the second molded product perpendicular to the longitudinal direction, a distance in the first direction between an end portion of the preliminary top plate portion on the side of the surface scraping portion and an end portion of the preliminary vertical wall portion opposite to the surface scraping portion is approximately the same as a distance in the first direction between an end portion of the first top plate and an end portion of the vertical wall portion protruding from the end portion of the first top plate in a cross section of the press-molded product perpendicular to the longitudinal direction corresponding to the first cross section. Manufacturing method for press-molded products.

7. A method for manufacturing a press-molded product according to any one of claims 1 to 6, both ends of the top plate portion in the longitudinal direction are located on a second side opposite to the first side, the top plate portion includes a curved portion that is a portion curved so as to bulge toward the first side in a cross section along the longitudinal direction, The second molded product has the chamfered portion at a portion corresponding to the curved portion in the press-molded product. Manufacturing method for press-molded products.

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