Manufacturing method for press-formed products

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-formed product performed by press forming.

Background Art

[0002] As described in Patent Document 1, a technique for forming a member having a plate-shaped top plate portion extending in the longitudinal direction and a plate-shaped vertical wall portion protruding from an end portion in the width direction of the top plate by press forming is known.

[0003] In the manufacturing method disclosed in Patent Document 1, when forming the above member, a portion corresponding to the top plate portion of the workpiece is sandwiched between a first mold and a second mold. Then, a third mold arranged adjacent to the first mold is relatively moved with respect to the first mold and the second mold to form the vertical wall portion.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] According to the technique disclosed in Patent Document 1, since the member is formed in a state where the top plate portion is sandwiched between the first mold and the second mold, it is possible to suppress the occurrence of wrinkles on the top plate portion during press forming. However, in the method of Patent Document 1, during press forming, sufficient pressure cannot be applied to the vertical wall portion, and there is a possibility that wrinkles may occur in the vertical wall portion.

[0006] In one aspect of the present disclosure, it is desirable to suppress the occurrence of wrinkles during press forming.

Means for Solving the Problems

[0007] One aspect of the present disclosure is a method for manufacturing a press-formed product, comprising: forming a first molded product by press-forming a plate-shaped blank material; forming a second molded product by press-forming the first molded product; and forming a press-formed product by press-forming the second molded 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 that protrudes to the first side from both ends of the top plate portion in the width direction. The first molded product is a member extending in the longitudinal direction. The method for manufacturing a press-formed product further comprises a spare top plate portion, a beveled edge portion, and a flat portion. The spare top plate portion is an elongated plate-shaped portion extending in the longitudinal direction. The beveled edge portion is a plate-shaped portion that extends from the first end of the spare top plate portion in the width direction so as to bend to the first side. The flat portion is a plate-like part that extends from the end of the beveled portion opposite to the spare top plate portion. The second molded product is a member that extends in the longitudinal direction. The method for manufacturing the press-formed product further comprises a spare top plate portion, a beveled portion, and a spare vertical wall portion. The spare vertical wall portion is a wall-like part that protrudes toward the first side from the end of the beveled portion opposite to the spare top plate portion. The spare vertical wall portion is formed by deforming the flat portion while the spare top plate portion and the beveled portion of the first molded product are held between molds.

[0008] According to the above configuration, when forming the preliminary vertical wall portion, the preliminary top plate portion and the beveled edge portion of the first molded product are held between the mold. This suppresses the occurrence of wrinkles during press molding. In one aspect of this disclosure, the first molded product may be formed by sandwiching a blank material between a first mold located on the first side and a second mold located on the second side, which is opposite to the first side. The preliminary vertical wall portion may be formed by sandwiching the preliminary top plate portion and the bevel portion of the first molded product between the first mold and the second mold, and then pressing the flat portion from the second side with a third mold located on the second side.

[0009] According to the above configuration, a suitable pre-top plate section, a beveled edge section, and a pre-vertical wall section can be formed. In one aspect of the present disclosure, the press-formed product may be formed by clamping the spare top plate portion of the second molded product between a fourth die located on the second side opposite to the first side and a fifth die located on the first side, and then deforming the beveled portion by pressing it with a sixth die located on the first side.

[0010] According to the above configuration, the top plate and vertical wall portions can be suitably formed. In one aspect of this disclosure, when forming a press-formed product by press forming of a second molded product, the beveled portion and the preliminary vertical wall portion may come into contact with the fourth die and the sixth die.

[0011] According to the above configuration, vertical wall portions can be suitably formed. In one aspect of this disclosure, the second molded product may include a flange portion, which is a plate-like portion, that protrudes from the end of the pre-vertical wall portion opposite to the beveled portion. The flange portion in the second molded product may correspond to a part of the flat portion in the first molded product. When forming a press-formed product by press forming of the second molded product, the flange portion in the second molded product may come into contact with the fourth die and the sixth die.

[0012] According to the above configuration, a flange portion can be suitably formed. In one aspect of this disclosure, press forming for forming a first molded product, a second molded product, and a press-formed product may be performed by displacing a die along a first direction. The press-formed product may have a first top plate end located in the width direction of the top plate portion, which corresponds to a part of the beveled portion of the second molded product. The distance in the first direction between the end of the pre-prepared top plate portion on the beveled portion side and the end of the pre-prepared vertical wall portion on the opposite side of the beveled portion in a first cross section perpendicular to the longitudinal direction of the second molded product may be substantially the same as the distance in the first direction between the first top plate end and the end of the vertical wall portion protruding from the first top plate end in a cross section perpendicular to the longitudinal direction corresponding to the first cross section of the press-formed product.

[0013] According to the above configuration, the top plate and vertical wall portions can be suitably formed. In one aspect of the present disclosure, both longitudinal ends of the top plate portion may be located on the second side opposite to 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 surface shaving portion at a portion corresponding to the curved portion of the press-molded product.

[0014] According to the above configuration, it is possible to suppress the occurrence of wrinkles in the curved portion during press molding.

Brief Description of the Drawings

[0015] [Figure 1] It is a perspective view of a press-molded product. [Figure 2] It is a side view showing an end portion in the width direction of the press-molded product. [Figure 3] It is a top view of the press-molded product. [Figure 4] It is a side view showing an end portion in the longitudinal direction of the press-molded product. [Figure 5] It is an explanatory view showing the state at the start of the first step. [Figure 6] It is an explanatory view showing the state at the completion of the first step. [Figure 7] It is an explanatory view showing the state during press molding in the second step. [Figure 8] It is an explanatory view showing the state at the completion of the second step. [Figure 9] It is an explanatory view showing the state at the start of the third step. [Figure 10] It is an explanatory view showing the state at the completion of the third step.

Embodiments for Carrying Out 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 Product] The press-formed product 1 of the first embodiment is formed by press-forming a metal material (see Fig. 1). In the first embodiment, a high-tensile steel with a tensile strength of 980 MPa or more is used as the metal material. However, it is not limited to this. The metal material may be, for example, a high-tensile steel with a tensile strength of 1470 MPa or more, a high-tensile steel with a tensile strength of less than 980 MPa, stainless steel, or iron.

[0017] Also, as an example, the press-formed product 1 is used as a member constituting the vehicle body. However, it is not limited to this. The press-formed product 1 may be used as a member constituting parts other than the vehicle body in the vehicle, or may be used as a member not mounted on the vehicle.

[0018] The press-formed product 1 is a plate-like member and includes a top plate portion 12, a vertical wall portion 13, a flange portion 14, an opposite-side vertical wall portion 15, and an opposite-side 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. Also, the press-formed product 1 has a shape curved such that the first end 10 and the second end 11 protrude toward the second side D2, that is, in a cross-section along the longitudinal direction, the vicinity of the center bulges toward the first side D1 (see Fig. 2). Note that the first side D1 is the side where the flange portion 14 and the opposite-side 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, it is not limited to this, and the press-formed product 1 may have a shape that extends straight in a cross-section along the longitudinal direction.

[0019] The top plate portion 12 is an elongated plate-like part that extends along the longitudinal direction from the first end 10 to the second end 11. The portion from near the longitudinal center of the top plate portion 12 to the second end 11 becomes longer in the length in the width direction (hereinafter, also simply referred to as the width direction) of the press-formed product 1 as it goes from the first end 10 to the second end 11. The top plate portion 12 includes a curved portion 120.

[0020] The curved portion 120 is a plate-like part located in a cross-section along the longitudinal direction of the top plate portion 12, specifically in the portion that curves outward toward the first side D1. The curved portion 120 is located approximately in the center of the top plate portion 12 in the longitudinal direction.

[0021] The vertical wall portion 13 is a plate-like portion that protrudes from the widthwise end of the top plate portion 12 toward the first side D1, extending 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 stepped portion 131, a second stepped portion 132, and a lower vertical wall portion 133.

[0022] The upper vertical wall portion 130 is a wall-like portion that protrudes from the widthwise end of the top plate portion 12 toward the first side D1. The first stepped portion 131 and the second stepped portion 132 are stepped portions located at the end of the upper vertical wall portion 130 opposite to the top plate portion 12, and protruding from the opposite side of the opposite vertical wall portion 15. The first stepped portion 131 and the second stepped portion 132 are aligned along the longitudinal direction, with the first stepped portion 131 located on the first end 10 side and the second stepped portion 132 located on the second end 11 side. Also, when viewed from the second side D2, the first stepped portion 131 is approximately triangular in shape (see Figure 3). One end of the first stepped portion 131 extends along the end of the upper vertical wall portion 130. Note that the vertical wall portion 13 does not necessarily have to include the first stepped portion 131 and the second stepped portion 132. In other words, the vertical wall portion 13 may be, for example, a wall-like portion that protrudes straight from the widthwise end of the top plate portion 12 to the first side D1 without bending.

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

[0024] The opposite vertical wall portion 15 is a plate-like portion of the top plate portion 12 that protrudes toward the first side D1 from the end opposite to the vertical wall portion 13. The opposite vertical wall portion 15 faces the vertical wall portion 13 in the width direction. The opposite vertical wall portion 15 may also have stepped portions, such as 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-formed product 1, the length of the opposite vertical wall portion 15 protruding to the first side D1 is preferably less than or equal to the length of the vertical wall portion 13 protruding to the first side D1, and more preferably less than the length of the vertical wall portion 13 protruding to the first side D1.

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

[0026] [1-3. Press forming apparatus in the first process] In the first step, a plate-shaped blank material B, which is made of the aforementioned metal material and extends along its longitudinal direction, is press-formed using a press forming device to form the first molded product 5 (see Figure 5).

[0027] The press molding apparatus in the first step comprises a first lower mold 2, an upper pad 3, and a first upper mold 4, which are molds for press molding. The first lower mold 2 is located below the blank material B. The first lower mold 2 has a shape that extends along the longitudinal direction and has a shape that protrudes upward in a cross section perpendicular to the longitudinal direction (hereinafter simply referred to as the cross section). The first lower mold 2 comprises a preliminary top plate forming section 20, a surface beveling 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 pre-top plate forming section 20 extends along the longitudinal direction and is a molding surface that forms the upper surface of the portion that protrudes above the first lower mold 2. The surface beveling section 21 is a molded surface that extends downward from one end in the width direction of the pre-top plate forming section 20, curving downwards.

[0029] The preliminary vertical wall forming section 22 is a forming surface that extends downward from the end of the surface beveling forming section 21 opposite to the preliminary top plate forming section 20. The preliminary vertical wall forming section 22 has a smaller angle with respect to the vertical direction than the surface beveling forming section 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 surface trimming portion 21, and on the opposite side of the opposite vertical wall forming portion 24.

[0030] The opposite vertical wall forming section 24 is a forming surface that extends downward from the end of the pre-top plate forming section 20 opposite to the surface beveling forming section 21. The opposite flange forming section 25 is a forming surface that extends from the end of the opposite vertical wall forming section 24 opposite to the pre-top plate forming section 20, and opposite to the flange forming section 23. The opposite flange forming section 25 is located above the flange forming section 23.

[0031] The upper pad 3 has a shape that extends along the longitudinal direction and is located on the upper side of the blank material 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 positioned facing the first lower mold 2 in the vertical direction. The upper pad 3 comprises a pre-top plate forming section 30 and a surface beveling forming section 31.

[0032] The pre-top plate forming section 30 is an elongated molding surface that extends along the longitudinal direction of the upper pad 3. The pre-top plate forming section 30 faces the pre-top plate forming section 20 of the first lower mold 2 in the vertical direction. The beveling section 31 is a molding surface that extends downward from the widthwise end of the pre-top plate forming section 30 on the pre-vertical wall forming section 22 side of the first lower mold 2, curving downward. The beveling section 31 faces the beveling section 21 of the first lower mold 2 in the vertical direction.

[0033] The first upper die 4 is a die for press forming. The first upper die 4 has a shape that extends along the longitudinal direction and is located on the upper side of the blank material B. The first upper die 4 is positioned facing the first lower die 2 in the vertical direction and is displaceable in the vertical direction. The first upper die 4 includes a preliminary vertical wall forming section 40, a flange forming section 41, an opposite vertical wall forming section 42, and an opposite flange forming section 43.

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

[0035] The flange forming portion 41 is a molding surface located on the lower part of the first upper mold 4. The flange forming portion 41 is located on the side of the surface trimming portion 31 in the width direction of the upper pad 3 and faces the flange forming portion 23 of the first lower mold 2 in the vertical direction.

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

[0037] The opposite flange forming portion 43 is a molding surface located on the lower part of the first upper mold 4. The opposite flange forming portion 43 is located on the side of the pre-top plate forming portion 30 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 vertical 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 Figure 5). Then, by displacing the upper pad 3 downwards, the blank material B is sandwiched between the first lower mold 2 and the upper pad 3 (see Figure 6).

[0039] At this time, the upper surface of the blank material B is in contact with the pre-top plate forming section 30 and the beveling section 31 of the upper pad 3, and the lower surface of the blank material B is in contact with the pre-top plate forming section 20 and the beveling section 21 of the first lower mold 2. In addition, the blank material B is deformed along the pre-top plate forming section 30 and the beveling section 31 by receiving pressure from the first lower mold 2 and the upper pad 3. As a result, the pre-top plate forming section 30 and the beveling section 31 are formed from the blank material B.

[0040] Through the above process, the first molded product 5 is formed from the blank material B. [1-5. 1st molded product] The first molded product 5 is a plate-shaped member extending along its longitudinal direction, and comprises a preliminary top plate portion 50, a beveled edge portion 51, a flat portion 52, and an opposite flat portion 53 (see Figure 6).

[0041] The spare top plate section 50 is a long, narrow, plate-like portion that extends along the longitudinal direction. The beveled portion 51 is a plate-like part that extends from one end in the width direction of the spare top plate portion 50, curving downward (in other words, towards the first side D1).

[0042] The flat portion 52 is a plate-like part of the beveled surface portion 51 that extends from the end opposite to the spare top plate portion 50. The opposite flat portion 53 is a plate-like part of the spare top plate portion 50 that extends from the end opposite to the beveled portion 51.

[0043] [1-6. 2nd process] In the second step, the first molded product 5 formed in the first step is held between the first lower mold 2 and the upper pad 3, and the first upper mold 4 is displaced downwards 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 comes into contact with the preliminary vertical wall forming portion 40 and the flange forming portion 41 of the first upper mold 4, and the lower surface of the flat portion 52 comes into contact with the preliminary vertical wall forming portion 22 and the flange forming portion 23 of the first lower mold 2.

[0045] Furthermore, the flat section 52 deforms along the preliminary vertical wall forming section 40 and the flange forming section 41 due to pressure from the first lower mold 2 and the first upper mold 4. As a result, the preliminary vertical wall section 62 and the flange section 63 are formed from the flat section 52 (see Figure 8).

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

[0047] Furthermore, the opposite flat portion 53 deforms along the opposite vertical wall forming portion 42 and the opposite flange forming portion 43 due to pressure from the first lower mold 2 and the first upper mold 4. As a result, the opposite vertical wall portion 64 and the opposite flange portion 65 are formed from the opposite flat portion 53.

[0048] Through the above process, 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 its longitudinal direction, and comprises a preliminary top plate portion 60, a beveled edge 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 spare top plate section 60 is a long, narrow, plate-like portion that extends along the longitudinal direction. The beveled portion 61 is a plate-like part that extends downward from one end in the width direction of the pre-top plate portion 60, curving downward. In the second step, the angle of the beveled portion 61 with respect to the vertical direction of press forming may, for example, be 40° or more and less than 90°.

[0050] The spare vertical wall portion 62 is a plate-like portion that protrudes downward from the end of the beveled surface portion 61 opposite to the spare 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 to the beveled portion 61, and on the opposite side of the opposite vertical wall portion 64.

[0051] The opposite vertical wall portion 64 is a plate-like portion that protrudes downward from the end of the spare top plate portion 60 opposite to the beveled edge portion 61. The opposite vertical wall portion 64 faces the spare vertical wall portion 62 in the width direction.

[0052] The opposite flange portion 65 is a plate-shaped part of the opposite vertical wall portion 64 that protrudes from the end opposite to the spare top plate portion 60 and toward the opposite side of the spare vertical wall portion 62. The spare top plate portion 60 and the beveled edge portion 61 in the second molded product 6 correspond to the spare top plate portion 50 and the beveled edge portion 51 in the first molded product 5. Also, the opposite vertical wall portion 64 and the opposite flange portion 65 correspond to the opposite vertical wall portion 15 and the opposite flange portion 16 in the press-formed 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 to form the press-molded product 1.

[0054] The press molding apparatus in the third step comprises a second upper mold 7, a lower pad 8, and a second lower mold 9, which are press molding dies (see Figure 9). The second upper mold 7 is located above the second molded product 6 and is displaceable in the vertical direction. The second upper mold 7 has a shape that extends along the longitudinal direction and has a cross-sectional shape in which the lower surface is recessed upward. The second upper mold 7 comprises a top plate forming portion 70, a vertical wall forming portion 71, a flange contact portion 72, an opposite vertical wall contact portion 73, and an opposite flange contact portion 74.

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

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

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

[0058] The lower pad 8 has a shape that extends along the longitudinal direction and has a cross-sectional shape in which the upper surface protrudes 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 positioned facing the second upper mold 7. The lower pad 8 includes a spare top plate contact portion 80, an opposite vertical wall contact portion 81, and an opposite flange contact portion 82.

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

[0060] The opposite vertical wall contact portion 81 is a molding surface that extends downward from the end in the width direction opposite to the second lower mold 9 of the spare top plate contact portion 80. The opposite vertical wall contact portion 81 faces the opposite vertical wall contact portion 73 of the second upper mold 7 in the vertical direction.

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

[0062] The second lower mold 9 has a shape that extends along its longitudinal direction and has a cross-sectional shape in which its upper surface protrudes upward. The second lower mold 9 is located below the second molded product 6 and is positioned facing the second upper mold 7. The second lower mold 9 includes a top plate forming section 90, a vertical wall forming section 91, and a flange contact section 92.

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

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

[0065] The flange contact portion 92 is a molding surface that extends from the end of the vertical wall forming portion 91 opposite to the top plate forming portion 90, toward the side opposite to the lower pad 8. The flange contact portion 92 faces the flange contact 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. The second molded product 6 is then sandwiched and held between the second upper mold 7 and the lower pad 8 (see Figure 9).

[0067] At this time, the spare top plate portion 60 of the second molded product 6 abuts against the top plate forming portion 70 of the second upper mold 7 and the spare top plate contact portion 80 of the lower pad 8, and the opposite vertical wall portion 64 abuts against the opposite vertical wall contact portion 73 of the second upper mold 7 and the opposite vertical wall contact portion 81 of the lower pad 8. The opposite flange portion 65 abuts against the opposite flange contact portion 74 of the second upper mold 7 and the opposite flange contact portion 82 of the lower pad 8. In addition, the upper surface of the spare vertical wall portion 62 abuts against the vertical wall forming portion 71 of the second upper mold 7, and the upper surface of the flange portion 63 abuts against the flange contact portion 72 of the second upper mold 7. On the other hand, a gap is created between the beveled portion 61 and the top plate forming portion 70 and the vertical wall forming portion 71.

[0068] Then, by displacing the second molded product 6 downward while it is held between the second upper mold 7 and the lower pad 8, the beveled portion 61 is pressed by the second lower mold 9 (see Figure 10). When the beveled portion 61 is pressed by the second lower die 9, the upper surface of the beveled 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 beveled 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 auxiliary 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 contact portion 72, and the lower surface abuts against the flange contact portion 92.

[0069] Then, the beveled surface portion 61 deforms along the top plate forming portion 70 and the vertical wall forming portion 71 due to pressure from the second upper die 7 and the second lower die 9. 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 spare top plate portion 60, the beveled edge portion 61, and the spare vertical wall portion 62. Through the above process, the press-molded product 1 is formed from the second molded product 6.

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

[0072] In this case, regardless of which position along the entire longitudinal region is designated as the first cross-section, the first distance and the second distance will be approximately the same. In other words, when forming the press-molded product 1 from the second molded product 6 in the third step, the height in the vertical direction will not change significantly. [1-10. Effects] According to the first embodiment described in detail above, the following effects can be obtained.

[0073] (1) When forming a press-formed product 1 from a blank material B in a single press-forming process, it is conceivable to form the vertical wall portion 13 by pressing the top plate portion 12 while it is clamped in a die in order to suppress the flow of material in the top plate portion 12 and to suppress the occurrence of cracks and wrinkles. However, this method does not allow sufficient pressure to be applied to the vertical wall portion 13, which may cause wrinkles to occur in the vertical wall portion 13. In particular, there is a risk of wrinkles occurring in the part 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 flat portion 52 is deformed to form the preliminary vertical wall portion 62 while the preliminary top plate portion 50 and the trimmed portion 51 of the first molded product 5 are held between the upper pad 3 and the first lower mold 2.

[0075] Therefore, during the press molding process in the second step, the flow of material in the pre-filled top plate portion 50 and the trimmed portion 51 can be suppressed, thereby preventing wrinkles from forming in the pre-filled top plate portion 50 and the trimmed portion 51 of the second molded product 6.

[0076] (2) Furthermore, when forming a press-formed product 1 from a blank material B in a single press-forming process, the vertical wall portion 13, which has a high vertical height, is formed in a single press-forming process. As a result, the amount of material that flows during press-forming increases, and there is a risk that wrinkles may occur 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 a single press molding is reduced.

[0078] Therefore, it is possible to suppress the occurrence of wrinkles in the preliminary vertical wall portion 62 of the second molded product 6 during the press molding process in the second step. (3) In the manufacturing method of the above embodiment, the first molded product 5 is formed in the first step by sandwiching the blank material B between the first lower mold 2 and the upper pad 3. Then, with the first molded product 5 still sandwiched between the first lower mold 2 and the upper pad 3, the second molded product 6 is formed by pressing the flat portion 52 with the first upper mold 4.

[0079] With this configuration, the preliminary top plate portion 60, the beveled edge 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 spare top plate portion 60, the opposite vertical wall portion 64, and the opposite flange portion 65 of the second molded product 6 are clamped by the second upper die 7 and the lower pad 8. Then, with the second molded product 6 clamped, the bevel portion 61 is pressed and deformed by the second lower die 9 to form the press-molded product 1.

[0080] Therefore, during the press forming process in the third step, the flow of material in the preliminary top plate portion 60, the opposite vertical wall portion 64, and the opposite flange portion 65 of the second molded product 6 can be suppressed, and the occurrence of wrinkles in the top plate portion 12, the opposite vertical wall portion 15, and the opposite flange portion 16 of the press-formed product 1 can be suppressed.

[0081] (5) In addition, in the manufacturing method of the above embodiment, during press forming in the third step, the beveled portion 61, the preliminary vertical wall portion 62 and the flange portion 63 of the second molded product 6 come into contact with the second upper die 7 and the second lower die 9.

[0082] This configuration suppresses excessive material flow during press forming in the third step, thereby preventing wrinkles from forming in the press-formed product 1. (6) In addition, in the manufacturing method of the above embodiment, the beveled portion 61 of the second molded product 6 is provided with ridges extending along the longitudinal direction at both ends in the width direction. This increases the rigidity around the beveled portion 61 of the second molded product 6.

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

[0084] In contrast, in the manufacturing method of the above embodiment, the second molded product 6 is provided with a beveled portion 61 in the portion corresponding to the curved portion 120 of the press-molded product 1. Therefore, it is possible to suppress the occurrence of wrinkles in the area near the curved portion 120 of the vertical wall portion 13 of the press-formed product 1.

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

[0086] [2. Other Embodiments] (1) In the above embodiment, the second molded product 6 is provided with a beveled edge 61 along its entire length in the longitudinal direction. However, the second molded product 6 is not limited to this, and may be provided with a beveled edge 61 only in a part of its longitudinal direction. For example, the second molded product 6 may be provided with a beveled edge 61 only in the portion corresponding to the curved portion 120 of the press-molded product 1. Furthermore, in the above embodiment, the second molded product 6 is provided with a beveled edge 61 at one end in the width direction of the spare top plate portion 60. However, the second molded product 6 is not limited to this, and may be provided with beveled edges 61 at both ends in the width direction of the spare top plate portion 60.

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

[0088] (3) In the above embodiment, each mold used in each process was 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 having a pre-top plate forming section 30 and a mold having a surface trimming forming section 31.

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

[0090] (5) Multiple functions of one component in the above embodiment 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. Furthermore, some of the configurations of the above embodiment may be omitted. Furthermore, at least some of the configurations of the above embodiment may be added to or replaced with the configurations of other above embodiments.

[0091] [3. The technical concept disclosed herein] [Item 1] A method for manufacturing press-formed products, The first molded product is formed by press forming of a plate-shaped blank material, The second molded product is formed by press molding of the first molded product, The method comprises forming the press-formed product by press forming the second molded product, The aforementioned press-formed product is a member that extends in the longitudinal direction, The top plate portion is an elongated, plate-like part extending in the longitudinal direction, The top plate portion comprises vertical wall portions, which are wall-like parts that protrude to the first side from both ends in the width direction of the top plate portion, The first molded product is a member extending in the longitudinal direction, The aforementioned elongated plate-shaped portion extending in the longitudinal direction is the pre-top plate portion, A beveled portion, which is a plate-like part extending from the first end in the width direction of the aforementioned spare top plate portion so as to bend toward the first side, The aforementioned beveled portion includes a flat portion, which is a plate-like part, extending from the end opposite to the aforementioned spare top plate portion, The second molded product is a member extending in the longitudinal direction, The aforementioned spare top plate section, The aforementioned surface beveling portion, The surface beveling portion includes a pre-vertical wall portion, which is a wall-like portion that protrudes toward the first side from the end opposite to the pre-top plate portion, The aforementioned pre-vertical wall portion is formed by deforming the flat portion while the pre-top portion and the trimmed portion of the first molded product are held in place by the mold. A method for manufacturing press-formed products.

[0092] [Item 2] A method for manufacturing a press-formed product as described in item 1, The first molded product is formed by sandwiching the blank material between a first mold located on the first side and a second mold located on the second side, which is opposite to the first side. The aforementioned pre-vertical wall portion is formed by pressing the flat portion from the second side with a third mold positioned on the second side, while the pre-top portion and the trimmed portion of the first molded product are sandwiched between the first mold and the second mold. A method for manufacturing press-formed products.

[0093] [Item 3] A method for manufacturing a press-formed article as described in item 1 or item 2, The press-formed product is formed by clamping the pre-top plate portion of the second molded product between a fourth die positioned on the second side opposite to the first side and a fifth die positioned on the first side, and then deforming the beveled portion by pressing it with a sixth die positioned on the first side. A method for manufacturing press-formed products.

[0094] [Item 4] A method for manufacturing a press-formed product as described in item 3, When forming the press-formed product by press forming of the second molded product, the beveled portion and the preliminary vertical wall portion come into contact with the fourth mold and the sixth mold. A method for manufacturing press-formed products.

[0095] [Item 5] A method for manufacturing a press-formed product as described in item 4, The second molded product includes a flange portion, which is a plate-like portion, that protrudes from the end of the pre-cut vertical wall portion opposite to the beveled portion, The flange portion in the second molded product corresponds to a part of the flat portion in the first molded product, When forming the press-formed product by press forming of the second molded product, the flange portion of the second molded product comes into contact with the fourth mold and the sixth mold. A method for manufacturing press-formed products.

[0096] [Item 6] A method for manufacturing a press-formed product as described in any one of items 1 to 5, Press forming for forming the first molded product, the second molded product, and the press-formed product is performed by displacing the mold along the first direction. The press-formed product has an end portion located in the width direction of the top plate portion, which is a first top plate end portion corresponding to a part of the beveled portion of the second molded product, In the first cross-section of the second molded product perpendicular to the longitudinal direction, the distance in the first direction between the end of the spare top plate portion on the beveled side and the end of the spare vertical wall portion opposite to the beveled portion is substantially the same as the distance in the first direction between the end of the first top plate portion and the end of the vertical wall portion protruding from the end of the first top plate portion in the cross-section of the press-formed product perpendicular to the longitudinal direction corresponding to the first cross-section. A method for manufacturing press-formed products.

[0097] [Item 7] A method for manufacturing a press-formed product as described in any one of items 1 to 6, Both ends of the top plate portion in the longitudinal direction are located on the second side opposite to the first side. The top plate portion includes a curved portion in a cross-section along the longitudinal direction, which is a portion that curves so as to bulge toward the first side. The second molded product is provided with the beveled portion in the portion corresponding to the curved portion of the press-formed product. A method for manufacturing press-formed products. [Explanation of Symbols]

[0098] 1...Press-formed product, 12...Top plate section, 13...Vertical wall section, 15...Vertical wall section on the opposite side, 2...First lower die, 3...Upper pad, 4...First upper die, 5...First molded product, 50...Spare top plate section, 51...Beveled edge section, 52...Flat section, 6...Second molded product, 60...Spare top plate section, 61...Beveled edge section, 62...Spare vertical wall section, B...Blank material, D1...First side, D2...Second side.

Claims

1. A method for manufacturing press-formed products, The first molded product is formed by press forming of a plate-shaped blank material, The second molded product is formed by press molding of the first molded product, The method comprises forming the press-formed product by press forming the second molded product, The aforementioned press-formed product is a member that extends in the longitudinal direction, The top plate portion is an elongated, plate-like part extending in the longitudinal direction, The top plate portion comprises vertical wall portions, which are wall-like parts that protrude to the first side from both ends in the width direction of the top plate portion, The first molded product is a member extending in the longitudinal direction, The aforementioned elongated plate-shaped portion extending in the longitudinal direction is the pre-top plate portion, A beveled portion, which is a plate-like part extending from the first end in the width direction of the aforementioned spare top plate portion so as to bend toward the first side, The aforementioned beveled portion includes a flat portion, which is a plate-like part, extending from the end opposite to the aforementioned spare top plate portion, The second molded product is a member extending in the longitudinal direction, The aforementioned spare top plate section, The aforementioned surface beveling portion, The surface beveling portion includes a pre-vertical wall portion, which is a wall-like portion that protrudes toward the first side from the end opposite to the pre-top plate portion of the surface beveling portion, The aforementioned pre-vertical wall portion is formed by deforming the flat portion while the pre-top portion and the trimmed portion of the first molded product are held in place by the mold. A method for manufacturing press-formed products.

2. A method for manufacturing a press-formed article according to claim 1, The first molded product is formed by sandwiching the blank material between a first mold located on the first side and a second mold located on the second side, which is opposite to the first side. The aforementioned pre-vertical wall portion is formed by pressing the flat portion from the second side with a third mold positioned on the second side, while the pre-top portion and the trimmed portion of the first molded product are sandwiched between the first mold and the second mold. A method for manufacturing press-formed products.

3. A method for manufacturing a press-formed article according to claim 1, The press-formed product is formed by clamping the pre-top plate portion of the second molded product between a fourth die positioned on the second side opposite to the first side and a fifth die positioned on the first side, and then deforming the beveled portion by pressing it with a sixth die positioned on the first side. A method for manufacturing press-formed products.

4. A method for manufacturing a press-formed product according to claim 3, When forming the press-formed product by press forming of the second molded product, the beveled portion and the preliminary vertical wall portion come into contact with the fourth mold and the sixth mold. A method for manufacturing press-formed products.

5. A method for manufacturing a press-formed article according to claim 4, The second molded product includes a flange portion, which is a plate-like portion, that protrudes from the end of the pre-cut vertical wall portion opposite to the beveled portion, The flange portion in the second molded product corresponds to a part of the flat portion in the first molded product, When forming the press-formed product by press forming of the second molded product, the flange portion of the second molded product comes into contact with the fourth mold and the sixth mold. A method for manufacturing press-formed products.

6. A method for manufacturing a press-formed article according to claim 1, Press forming for forming the first molded product, the second molded product, and the press-formed product is performed by displacing the mold along the first direction. The press-formed product has an end portion located in the width direction of the top plate portion, which is a first top plate end portion corresponding to a part of the beveled portion of the second molded product, In the first cross-section of the second molded product perpendicular to the longitudinal direction, the distance in the first direction between the end of the spare top plate portion on the beveled side and the end of the spare vertical wall portion opposite to the beveled portion is substantially the same as the distance in the first direction between the end of the first top plate portion and the end of the vertical wall portion protruding from the end of the first top plate portion in the cross-section of the press-formed product perpendicular to the longitudinal direction corresponding to the first cross-section. A method for manufacturing press-formed products.

7. A method for manufacturing a press-formed article according to any one of claims 1 to 6, Both ends of the top plate portion in the longitudinal direction are located on the second side opposite to the first side. The top plate portion includes a curved portion in a cross-section along the longitudinal direction, which is a portion that curves so as to bulge toward the first side. The second molded product is provided with the beveled portion in the portion corresponding to the curved portion of the press-formed product. A method for manufacturing press-formed products.

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