Manufacturing method of press-molded products

Abstract

To provide a technique for reducing a burden on a trim blade when removing an excessive thick portion from an intermediate formed product by trimming processing in a manufacturing method of a press-formed product which has a first wall part, a second wall part crossing the first wall part, and a bending part for connecting the first wall part and the second wall part.SOLUTION: A manufacturing method of a press-formed product includes: forming a penetration part in a processed material; forming an intermediate formed product formed with a first wall part, a second wall part, and a bending part by bending the processed material formed with the penetration part; and removing an excessive thick portion from the intermediate formed product to obtain the press-formed product. The penetration part is formed in the processed material so that a border line between the second wall part and the excessive thick portion crosses the bending part in the intermediate formed product. The excessive thick portion is removed from the intermediate formed product due to that the intermediate formed product is cut from a direction crossing the first wall part along a border line between the first wall part and the excessive thick portion, and is cut from a direction crossing the second wall part along the border line between the second wall part and the excessive thick portion.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present disclosure relates to a manufacturing method for a press-molded product having a first wall portion, a second wall portion intersecting the first wall portion, and a bent portion connecting the first wall portion and the second wall portion. [Background technology]

[0002] In some cases, the end portions of press-formed products may deviate from the target shape after press working. Therefore, as described in Patent Document 1, for example, it has been proposed to form an intermediate product having excess material at the end portions by press working, and then remove the excess material from the intermediate product by trimming, thereby making it easier to obtain a press-formed product having a target shape. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-62664 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, for example, as described in Patent Document 1, when the intermediate molded product has a top plate portion and a vertical wall portion and part of the vertical wall portion is included in the excess material portion, there was a problem that the load on the trim blade was likely to be large when removing the excess material portion from the intermediate molded product by trimming processing.

[0005] One aspect of the present disclosure provides a technique for reducing the load on a trim blade when removing excess material from an intermediate molded product by trimming in a manufacturing method for a press-molded product having a first wall portion, a second wall portion intersecting the first wall portion, and a bent portion connecting the first wall portion and the second wall portion. [Means for solving the problem]

[0006] One aspect of the present disclosure is a method for manufacturing a press-molded product having a first wall portion, a second wall portion intersecting the first wall portion, and a bent portion connecting the first wall portion and the second wall portion. The method for manufacturing the press-molded product includes the following steps (i) to (iii).

[0007] (i) Forming a penetration in the workpiece that passes through the workpiece. (ii) Bending the workpiece in which the through portion is formed to form an intermediate molded product in which the first wall portion, the second wall portion, and the bent portion are formed. (iii) Obtaining a press-formed product by removing excess material portions, which are portions of the intermediate product that are continuous with the first wall portion, the second wall portion and the bent portion, from the intermediate product.

[0008] The through portion is formed in the workpiece so that the through portion is located at a position in the intermediate molded product where the boundary between the second wall portion and the excess pad portion intersects with the bent portion. The intermediate molded product is cut along the boundary between the first wall portion and the excess pad portion from a direction intersecting with the first wall portion, and cut along the boundary between the second wall portion and the excess pad portion from a direction intersecting with the second wall portion, thereby removing the excess pad portion from the intermediate molded product.

[0009] According to this configuration, in a manufacturing method for a press-molded product having a first wall portion, a second wall portion intersecting the first wall portion, and a bent portion connecting the first wall portion and the second wall portion, the load on the trim blade can be reduced when removing excess material from the intermediate molded product by trimming.

[0010] In one aspect of the present disclosure, the through-hole may be formed in the workpiece so as to overlap the bent portion over the entire bending direction of the bent portion in the intermediate molded product. With this configuration, in a manufacturing method for a press-molded product having a first wall portion, a second wall portion intersecting the first wall portion, and a bent portion connecting the first wall portion and the second wall portion, it is possible to further reduce the load on the trimming blade when removing the excess material from the intermediate molded product by trimming.

[0011] In one embodiment of the present disclosure, at least a portion of the second wall may be curved so as to bulge toward the first wall. In such a configuration, the problem of a large load on the trim blade is more likely to occur, so it is more useful to reduce the load on the trim blade when removing the excess material from the intermediate molded product by trimming.

[0012] In one embodiment of the present disclosure, the intermediate molded product may be cut along a boundary line between the first wall portion and the excess pad portion from a direction perpendicular to the first wall portion, and cut along a boundary line between the second wall portion and the excess pad portion from a direction perpendicular to the second wall portion. According to this configuration, in a manufacturing method for a press-molded product having a first wall portion, a second wall portion intersecting with the first wall portion, and a bent portion connecting the first wall portion and the second wall portion, it is possible to further reduce the load on the trimming blade when removing the excess pad portion from the intermediate molded product by trimming.

[0013] In one embodiment of the present disclosure, the workpiece may be made of high tensile steel. In such a configuration, the problem of a large load on the trimming blade is more likely to occur, so it is more useful to reduce the load on the trimming blade when removing the excess material from the intermediate molded product by trimming. [Brief description of the drawings]

[0014] [Figure 1] FIG. 1 is a perspective view of a press-formed product according to a first embodiment. [Diagram 2] FIG. 4 is another perspective view of the press-formed product according to the first embodiment. [Diagram 3] FIG. 2 is a front view of the press-formed product according to the first embodiment. [Figure 4] FIG. 2 is a flow diagram of a method for manufacturing a press-molded product according to the first embodiment. [Diagram 5] FIG. 2 is a plan view of the workpiece after the blanking step according to the first embodiment has been performed. [Figure 6] FIG. 2 is a perspective view of an intermediate molded product molded in an intermediate molding step according to the first embodiment. [Figure 7]FIG. 4 is another perspective view of the intermediate molded product molded in the intermediate molding step according to the first embodiment. [Figure 8] FIG. 8 is a cross-sectional view taken along line VIII-VIII of FIG. 7. [Figure 9] FIG. 2 is a perspective view of an intermediate molded product after a first trimming step according to the first embodiment has been performed. [Figure 10] FIG. 11 is a perspective view of a press-formed product according to a second embodiment. [Figure 11] FIG. 11 is a perspective view of an intermediate molded product molded in an intermediate molding step according to the second embodiment. [Figure 12] 12A and 12B are perspective views of intermediate molded products showing modified examples of the through-hole portion. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Hereinafter, exemplary embodiments of the present disclosure will be described with reference to the drawings.

[0016] [1. First embodiment] [1-1. Composition of press-molded products] The press-formed product 1 shown in Fig. 1 to Fig. 3 is a component part of an automobile body. The press-formed product 1 is made of high-tensile steel material having high tensile strength. For example, the press-formed product 1 may be made of high-tensile steel material having a tensile strength of 980 MPa or more, or may be made of high-tensile steel material having a tensile strength of 1180 MPa or more. The press-formed product 1 of this embodiment is made of high-tensile steel material having a tensile strength of 1470 MPa.

[0017] The press-formed product 1 includes a first wall portion 11, a second wall portion 12, a third wall portion 13, a first bent portion 14, and a second bent portion 15.

[0018] The first wall portion 11 is a plate-like portion extending in a predetermined direction. The first wall portion 11 in this embodiment is flat. The first wall portion 11 has a constant width portion 111 and a widening portion 112. The constant width portion 111 and the widening portion 112 are connected to each other in the extension direction of the first wall portion 11. The constant width portion 111 is a portion having a constant width. The widening portion 112 is a portion whose width increases as it moves away from the constant width portion 111. The widths of the constant width portion 111 and the widening portion 112 refer to the lengths of the constant width portion 111 and the widening portion 112 in a direction perpendicular to the center line W of the first wall portion 11 shown in FIG. 3. More specifically, the center line W of the first wall portion 11 is a center line W along the extension direction of the first wall portion 11. The center line W of the first wall portion 11 is curved toward the first bent portion 14 at the widening portion 112.

[0019] As shown in Figs. 1 and 2, the second wall portion 12 is a plate-shaped portion that intersects with the first wall portion 11. In this embodiment, the second wall portion 12 is generally perpendicular to the first wall portion 11. The second wall portion 12 is continuous with one edge of the first wall portion 11 in a direction perpendicular to the center line W via the first bent portion 14. The second wall portion 12 extends along the edge of the first wall portion 11. In other words, the second wall portion 12 extends along the first bent portion 14. The length of the second wall portion 12 along the first bent portion 14 is shorter than the length of the first wall portion 11 along the first bent portion 14.

[0020] The third wall portion 13 is a plate-shaped portion intersecting with the first wall portion 11. The third wall portion 13 in this embodiment is generally perpendicular to the first wall portion 11. The third wall portion 13 faces the second wall portion 12. The third wall portion 13 is continuous with the other edge of the first wall portion 11 in the direction perpendicular to the center line W (i.e., the edge opposite the second wall portion 12 side) via the second bent portion 15. The third wall portion 13 extends along the edge of the first wall portion 11. In other words, the third wall portion 13 extends along the second bent portion 15. The length of the third wall portion 13 along the second bent portion 15 is generally equal to the length of the first wall portion 11 along the second bent portion 15.

[0021] The first bent portion 14 is a portion extending between the first wall portion 11 and the second wall portion 12 along an edge of the adjacent first wall portion 11. The first bent portion 14 connects the first wall portion 11 and the second wall portion 12. The cross-sectional shape of the first bent portion 14 perpendicular to the extension direction is an arc shape.

[0022] 3, at least a part of the ridge of the first bent portion 14 is curved so as to bulge toward the first wall portion 11. This can also be said to mean that at least a part of the second wall portion 12 is curved so as to bulge toward the first wall portion 11. In this embodiment, a portion of the second wall portion 12 that is continuous with the widened portion 112 of the first wall portion 11 is curved so as to bulge toward the first wall portion 11. That is, the ridge of the first bent portion 14, specifically, the portion that connects the widened portion 112 of the first wall portion 11 and the second wall portion 12, is curved so as to bulge toward the first wall portion 11.

[0023] 1 and 2, the second bent portion 15 is a portion extending between the first wall portion 11 and the third wall portion 13 along an edge of the adjacent first wall portion 11. The second bent portion 15 connects the first wall portion 11 and the third wall portion 13. The cross-sectional shape of the second bent portion 15 perpendicular to the extension direction is an arc shape.

[0024] [1-2. Manufacturing methods for press-molded products] As shown in FIG. 4, the method for manufacturing the press-formed product 1 includes a blanking step S1, an intermediate forming step S2, a first trimming step S3, and a second trimming step S4.

[0025] [1-2-1. Blanking process] In the blanking step S1, a punching process is performed on a workpiece 2. The workpiece 2 is a plate-like member that will be the material of the press-molded product 1. Before the blanking step S1 is performed, the workpiece 2 is in the shape of a flat plate.

[0026] In the blanking step S1, the following outer peripheral part removal process and through-hole forming process are performed as one process. In other words, these processes are performed simultaneously. Fig. 5 shows the workpiece 2 after the blanking step S1 has been performed, i.e., after all processes included in the blanking step S1 have been performed.

[0027] <Outer periphery removal processing> In the outer periphery removal process, the outer periphery of the workpiece 2 is removed by punching. As a result, the workpiece 2 is formed into the shape shown in Fig. 5. After the outer periphery removal process is performed, the workpiece 2 comprises a first shaped portion 21, a second shaped portion 22, a third shaped portion 23, and an excess portion 24.

[0028] The first molded portion 21 is a portion corresponding to the first wall portion 11 in the finished press-molded product 1. In other words, the first molded portion 21 is a portion where the first wall portion 11 is formed.

[0029] The second molded portion 22 is a portion corresponding to the second wall portion 12 in the finished press-molded product 1. In other words, the second molded portion 22 is a portion where the second wall portion 12 is formed. The second molded portion 22 is continuous with the first molded portion 21.

[0030] The third molded portion 23 is a portion corresponding to the third wall portion 13 in the finished press-molded product 1. In other words, the third molded portion 23 is a portion where the third wall portion 13 is formed. The third molded portion 23 is continuous with the first molded portion 21 on the side opposite to the second molded portion 22 side.

[0031] The excess metal portion 24 is a portion that is removed in the process of manufacturing the press-formed product 1 from the workpiece 2. The excess metal portion 24 is provided at an end of the workpiece 2. The excess metal portion 24 is continuous with both the first formed portion 21 and the second formed portion 22. Specifically, the excess metal portion 24 is continuous with both a portion of the first formed portion 21 that corresponds to the widened portion 112 of the first wall portion 11, and a portion of the second formed portion 22 that is continuous with the corresponding portion of the first formed portion 21.

[0032] The boundary line X1 between the first molded portion 21 and the second molded portion 22 and the boundary line X2 between the first molded portion 21 and the excess pad portion 24 form a single line. The boundary line X3 between the second molded portion 22 and the excess pad portion 24 intersects with the boundary line X1 between the first molded portion 21 and the second molded portion 22 and the boundary line X2 between the first molded portion 21 and the excess pad portion 24.

[0033] <Penetrating part forming process> In the through-portion forming process, a through-portion 25 shown in Fig. 5 is formed in the workpiece 2 by punching. The through-portion 25 is a hole that penetrates the workpiece 2 in the thickness direction. The through-portion 25 in this embodiment is a round hole.

[0034] The through portion 25 is formed at a position in the workpiece 2 where a boundary line X1 between the first molded portion 21 and the second molded portion 22 intersects with a boundary line X3 between the second molded portion 22 and the excess pad portion 24. In other words, the through portion 25 is formed at a position in the workpiece 2 where the first molded portion 21, the second molded portion 22, and the excess pad portion 24 contact each other.

[0035] [1-2-2. Intermediate forming process] In the intermediate forming process S2, press working is performed on the workpiece 2 after the blanking process S1. This results in the intermediate formed product 3 shown in Figures 6 and 7. In the intermediate forming process S2, the following first bending process, second bending process, first wall forming process, second wall forming process, and third wall forming process are performed as a single process. In other words, these processes are performed simultaneously. The intermediate formed product 3 is the workpiece 2 after all processes included in the intermediate forming process S2 have been performed (i.e., after the intermediate forming process S2 has been performed).

[0036] <First bending process> 5, in the first bending process, the workpiece 2 after the blanking step S1 is bent by press working along the boundary line X1 between the first shaped portion 21 and the second shaped portion 22. As a result, a first bent portion 14 is formed in the workpiece 2. The first bent portion 14 corresponds to a portion of the workpiece 2 that is bent along the boundary line X1 between the first shaped portion 21 and the second shaped portion 22.

[0037] In this embodiment, as described above, the boundary line X1 between the first forming portion 21 and the second forming portion 22 and the boundary line X2 between the first forming portion 21 and the excess material portion 24 form a single line. Therefore, in this embodiment, the workpiece 2 after the blanking step S1 is bent along these continuous boundary lines X1, X2. As a result, the workpiece 2 of this embodiment is formed with the first bent portion 14 and the extra bent portion 311a shown in FIG. 6. The extra bent portion 311a is a portion linearly connected to the first bent portion 14. The extra bent portion 311a corresponds to a portion of the workpiece 2 that is bent along the boundary line X2 between the first forming portion 21 and the excess material portion 24. The cross-sectional shape perpendicular to the extension direction of the extra bent portion 311a is an arc shape.

[0038] <Second bending process> 5, in the second bending process, the workpiece 2 after the blanking step S1 is bent by press working along the boundary line X4 between the first shaping portion 21 and the third shaping portion 23. As a result, a second bent portion 15 is formed in the workpiece 2. The second bent portion 15 corresponds to a portion of the workpiece 2 that is bent along the boundary line X4 between the first shaping portion 21 and the third shaping portion 23.

[0039] <First wall forming process> In the first wall portion forming process, the first molded portion 21 is formed by press working into a shape designed as the first wall portion 11. As a result, the first wall portion 11 is formed in the workpiece 2.

[0040] <Second wall forming process> In the second wall portion forming process, the second molded portion 22 is formed by press working into a shape designed as the second wall portion 12. As a result, the second wall portion 12 is formed in the workpiece 2.

[0041] <Third wall forming process> In the third wall portion forming process, the third molded portion 23 is formed by press working into a shape designed as the third wall portion 13. As a result, the third wall portion 13 is formed in the workpiece 2.

[0042] As shown in Fig. 6 and Fig. 7, the intermediate formed product 3 obtained by the intermediate forming step S2 includes a first wall portion 11, a second wall portion 12, a third wall portion 13, a first bent portion 14, a second bent portion 15, an excess pad portion 31, and a through portion 25. The excess pad portion 31 is a portion corresponding to the excess pad portion 24 in the workpiece 2 before the intermediate forming step S2 is performed. The excess pad portion 31 is provided at an end portion of the intermediate formed product 3. The excess pad portion 31 includes the above-mentioned excess bend portion 311a. The excess pad portion 31 is continuous with each of the first wall portion 11, the second wall portion 12, and the first bent portion 14. The boundary line Y1 between the first wall portion 11 and the excess pad portion 31 intersects with the boundary line Y2 between the second wall portion 12 and the excess pad portion 31.

[0043] In the intermediate molded product 3, the through portion 25 is located at a position where the boundary line Y2 between the second wall portion 12 and the excess metal portion 31 intersects with the first bent portion 14. That is, in the through portion forming process in the blanking step S1 described above, the through portion 25 is formed in the workpiece 2 such that in the intermediate molded product 3, the boundary line Y2 between the second wall portion 12 and the excess metal portion 31 intersects with the first bent portion 14. The position where the boundary line Y2 between the second wall portion 12 and the excess metal portion 31 intersects with the first bent portion 14 generally coincides with the position where the boundary line Y1 between the first wall portion 11 and the excess metal portion 31 and the boundary line Y2 between the second wall portion 12 and the excess metal portion 31 intersect with each other.

[0044] Hereinafter, the direction along the plate surface of the first bent portion 14 in a cross-sectional view perpendicular to the ridge line of the first bent portion 14 (i.e., as seen in FIG. 8) is referred to as the bending direction D of the first bent portion 14. As shown in FIG. 8, in the intermediate molded product 3, the through-hole 25 overlaps with the first bent portion 14 over the entire bending direction D of the first bent portion 14. That is, in the through-hole forming process in the blanking step S1 described above, the through-hole 25 is formed in the workpiece 2 so that in the intermediate molded product 3, the through-hole 25 overlaps with the first bent portion 14 over the entire bending direction D of the first bent portion 14.

[0045] [1-2-3. First trim process] As shown in FIG. 6, the excess pad portion 31 is composed of a first portion 311 and a second portion 312. The first portion 311 includes the excess bend portion 311a described above. The first portion 311 is defined by an outer edge of the excess pad portion 31, a boundary line Y1 between the first wall portion 11 and the excess pad portion 31 (more specifically, a boundary line between the first wall portion 11 and the excess bend portion 311a), and a cutting line Y3. The second portion 312 is defined by an outer edge of the excess pad portion 31, a boundary line Y2 between the second wall portion 12 and the excess pad portion 31, and a cutting line Y3. The cutting line Y3 is an imaginary line extending from the through portion 25 to the outer edge of the excess pad portion 31. The cutting line Y3 intersects with the boundary line Y1 between the first wall portion 11 and the excess pad portion 31 and the boundary line Y2 between the second wall portion 12 and the excess pad portion 31.

[0046] In the first trimming step S3, a trimming process is performed on the intermediate molded product 3 molded in the intermediate molding step S2. This removes the second portion 312 of the excess material portion 31. In the first trimming step S3, the following first cutting process and second cutting process are performed as one process. In other words, these processes are performed simultaneously. Figure 9 shows the intermediate molded product 3 after the first trimming step S3 has been performed, i.e., after all the processes included in the first trimming step S3 have been performed.

[0047] <1st cutting process> In the first cutting process, the intermediate molded product 3 molded in the intermediate molding process S2 is cut by trimming along the boundary line Y2 between the second wall portion 12 and the excess material portion 31. The boundary line Y2 between the second wall portion 12 and the excess material portion 31 corresponds to the line cut by trimming (so-called trim line). As shown by the hollow arrow in FIG. 6, the intermediate molded product 3 molded in the intermediate molding process S2 is cut from a direction intersecting with the second wall portion 12. In this embodiment, the intermediate molded product 3 is cut from a direction perpendicular to the second wall portion 12. The cutting direction of the intermediate molded product 3 coincides with the displacement direction of the trim blade used in the trimming process. The same applies below.

[0048] <Second cutting process> In the second cutting process, the intermediate molded product 3 molded in the intermediate molding process S2 is cut along a cutting line Y3 by a trimming process. The cutting line Y3 corresponds to a so-called trim line. As shown by the outlined arrow in Fig. 6, the intermediate molded product 3 molded in the intermediate molding process S2 is cut from a direction intersecting with the second wall portion 12. In this embodiment, the intermediate molded product 3 is cut from a direction perpendicular to the second wall portion 12.

[0049] [1-2-4. Second trim process] In the second trimming step S4, as shown in FIG. 9, the intermediate molded product 3 after the first trimming step S3 is trimmed. As a result, the first portion 311 of the excess material 31 is removed. Specifically, the intermediate molded product 3 after the first trimming step S3 is cut by trimming along the boundary line Y1 between the first wall portion 11 and the excess material 31. The boundary line Y1 between the first wall portion 11 and the excess material 31 corresponds to a so-called trim line. As shown by the white arrow in FIG. 9, the intermediate molded product 3 after the first trimming step S3 is cut from a direction intersecting with the first wall portion 11. In this embodiment, the intermediate molded product 3 is cut from a direction perpendicular to the first wall portion 11.

[0050] Through the first trimming step S3 and the second trimming step S4, the excess metal portion 31 is removed from the intermediate formed product 3. In this way, the press-formed product 1 shown in Figs. 1 to 3 is obtained.

[0051] [1-3. Effects] According to the first embodiment described above in detail, the following effects can be obtained.

[0052] (1a) The press-molded product 1 includes a first wall portion 11, a second wall portion 12, and a first bent portion 14. In the manufacturing method of the press-molded product 1 of this embodiment, a workpiece 2 is bent to form an intermediate product 3 having the first wall portion 11, the second wall portion 12, and the first bent portion 14. Thereafter, an excess portion 31 is removed from the intermediate product 3, and the press-molded product 1 is obtained.

[0053] Here, as a manufacturing method of the press-formed product 1, a method is also considered in which the workpiece 2 does not have the excess pad portion 24, and the press-formed product 1 is directly formed by bending the workpiece 2. In other words, a method is also considered in which the press-formed product 1 is directly manufactured from the workpiece 2 without going through the intermediate product 3. However, in this case, in the completed press-formed product 1, cracks may occur in the press-formed product 1 from the end portion in the extension direction of the first bent portion 14.

[0054] According to the manufacturing method of this embodiment, for example, it is possible to suppress the occurrence of cracks in the press-molded product 1 compared to the case where the press-molded product 1 is manufactured directly from the workpiece 2 without going through the intermediate product 3. Therefore, it is possible to easily obtain the press-molded product 1 having a target shape.

[0055] (1b) In the manufacturing method of the press-molded product 1 of this embodiment, the intermediate product 3 is cut from a direction intersecting with the first wall portion 11 along a boundary line Y1 between the first wall portion 11 and the excess pad portion 31. The intermediate product 3 is also cut from a direction intersecting with the second wall portion 12 along a boundary line Y2 between the second wall portion 12 and the excess pad portion 31. As a result, the excess pad portion 31 is removed from the intermediate product 3, and the press-molded product 1 is obtained.

[0056] According to this configuration, for example, compared to a case where the intermediate molded product 3 is cut from a direction parallel to the first wall portion 11 along the boundary line Y1 between the first wall portion 11 and the excess pad portion 31, or cut from a direction parallel to the second wall portion 12 along the boundary line Y2 between the second wall portion 12 and the excess pad portion 31, it is possible to reduce the dimension of the cut portion of the intermediate molded product 3 along the cutting direction. In other words, it is possible to reduce the dimension of the intermediate molded product 3 through which the trim blade must pass. Therefore, it is possible to reduce the load on the trim blade.

[0057] (1c) Particularly in this embodiment, the intermediate molded product 3 is cut from a direction perpendicular to the first wall portion 11 along a boundary line Y1 between the first wall portion 11 and the excess material portion 31. Also, the intermediate molded product 3 is cut from a direction perpendicular to the second wall portion 12 along a boundary line Y2 between the second wall portion 12 and the excess material portion 31. With this configuration, the load on the trim blade can be further reduced.

[0058] (1d) In the manufacturing method of the press-formed product 1 of this embodiment, before the workpiece 2 is bent, a through portion 25 is formed in the workpiece 2. The through portion 25 is formed in the workpiece 2 such that in the intermediate product 3, the boundary line Y2 between the second wall portion 12 and the excess material portion 31 intersects with the first bent portion 14.

[0059] According to this configuration, when the intermediate molded product 3 is cut along the boundary line Y1 between the first wall portion 11 and the excess pad portion 31 from the direction intersecting with the first wall portion 11, the intermediate molded product 3 can be prevented from being cut in a direction parallel to the first bent portion 14 at the edge of the excess pad portion 31 side of the first bent portion 14. Also, when the intermediate molded product 3 is cut along the boundary line Y2 between the second wall portion 12 and the excess pad portion 31 from the direction intersecting with the second wall portion 12, the intermediate molded product 3 can be prevented from being cut in a direction parallel to the first bent portion 14 at the edge of the excess pad portion 31 side of the first bent portion 14. Therefore, the dimension of the cut portion of the intermediate molded product 3 along the cutting direction can be further reduced. Therefore, the load on the trimming blade can be further reduced.

[0060] (1e) In the manufacturing method of the press-molded product 1 of the present embodiment, the through-hole 25 is formed in the workpiece 2 so as to overlap the first bent portion 14 over the entire bending direction D of the first bent portion 14 in the intermediate molded product 3. With this configuration, the effect of (1d) above can be further enhanced.

[0061] (1f) In the manufacturing method of the press-molded product 1 of this embodiment, the outer peripheral portion removal process and the through-hole formation process are performed in one process, the blanking process S1. With this configuration, the through-hole 25 can be formed in the workpiece 2 without increasing the number of processes. Therefore, the effects of (1d) and (1e) above can be obtained without increasing the number of processes.

[0062] (1g) At least a portion of the second wall portion 12 in the press-formed product 1 is curved so as to bulge toward the first wall portion 11. With such a configuration, if the press-formed product 1 were manufactured directly from the workpiece 2 without going through the intermediate product 3, the press-formed product 1 would be prone to cracking. For this reason, a method of manufacturing the press-formed product 1 from the workpiece 2 via the intermediate product 3, such as the manufacturing method of this embodiment, is likely to be applied. However, problems with the load on the trim blade when removing the excess material portion 31 from the intermediate product 3 are likely to occur. Therefore, as described in (1b) above, it is even more useful to apply the manufacturing method of this embodiment and reduce the load on the trim blade.

[0063] (1h) The workpiece 2 is made of high tensile steel. In such a structure, problems tend to occur with the load on the trim blade when removing the excess material 31 from the intermediate product 3. Therefore, as described above in (1b), it is even more useful to apply the manufacturing method of this embodiment and reduce the load on the trim blade.

[0064] [2. Second embodiment] [2-1. Composition of press-molded products] The press-formed product 4 of the second embodiment shown in FIG. 10 includes first to fifth wall portions 41 to 45 and first to fourth bent portions 46 to 49. As shown in FIG.

[0065] The first wall portion 41, the second wall portion 42, and the first bent portion 46 have substantially the same configuration as the first wall portion 11, the second wall portion 12, and the first bent portion 14 of the first embodiment. However, the first wall portion 41 and the second wall portion 42 are each substantially rectangular flat plate-like in a plan view. The length of the first wall portion 41 along the first bent portion 46 is equal to the length of the second wall portion 42 along the first bent portion 46. The ridge line of the first bent portion 14 is straight.

[0066] The third wall portion 43 is a flat plate-like portion parallel to the first wall portion 41. The third wall portion 43 intersects with the second wall portion 42. The third wall portion 43 is continuous with the edge of the second wall portion 42 on the opposite side to the first wall portion 41 side via the second bent portion 47. The third wall portion 43 extends along the second bent portion 47. The length of the third wall portion 43 along the second bent portion 47 is equal to the length of the second wall portion 42 along the second bent portion 47. The third wall portion 43 is disposed on the opposite side to the first wall portion 41 side across the second wall portion 42.

[0067] The fourth wall portion 44 is a flat plate-like portion parallel to the second wall portion 42. The fourth wall portion 44 intersects with the third wall portion 43. The fourth wall portion 44 is continuous with the edge of the third wall portion 43 on the opposite side to the second wall portion 42 side via the third bent portion 48. The fourth wall portion 44 extends along the third bent portion 48. The length of the fourth wall portion 44 along the third bent portion 48 is equal to the length of the third wall portion 43 along the third bent portion 48. The fourth wall portion 44 is disposed on the opposite side to the second wall portion 42 side across the third wall portion 43.

[0068] The fifth wall portion 45 is a flat plate-like portion parallel to the third wall portion 43. The fifth wall portion 45 intersects with the fourth wall portion 44. The fifth wall portion 45 is continuous with the edge of the fourth wall portion 44 opposite the third wall portion 43 side via the fourth bent portion 49. The fifth wall portion 45 extends along the fourth bent portion 49. The length of the fifth wall portion 45 along the fourth bent portion 49 is equal to the length of the fourth wall portion 44 along the fourth bent portion 49. The fifth wall portion 45 is disposed on the opposite side to the third wall portion 43 side across the fourth wall portion 44.

[0069] The second bent portion 47 is a portion extending along an edge of the adjacent second wall portion 42 between the second wall portion 42 and the third wall portion 43. The second bent portion 47 connects the second wall portion 42 and the third wall portion 43. The cross-sectional shape of the second bent portion 47 perpendicular to the extension direction is an arc shape.

[0070] The third bent portion 48 is a portion extending between the third wall portion 43 and the fourth wall portion 44 along an edge of the adjacent third wall portion 43. The third bent portion 48 connects the third wall portion 43 and the fourth wall portion 44. The cross-sectional shape of the third bent portion 48 perpendicular to the extension direction is an arc shape.

[0071] The fourth bent portion 49 is a portion extending between the fourth wall portion 44 and the fifth wall portion 45 along an edge of the adjacent fourth wall portion 44. The fourth bent portion 49 connects the fourth wall portion 44 and the fifth wall portion 45. The cross-sectional shape of the fourth bent portion 49 perpendicular to the extension direction is an arc shape.

[0072] The ridge lines of the second to fourth bent portions 47 to 49 are all straight. The ridge lines of the second to fourth bent portions 47 to 49 are parallel to the ridge line of the first bent portion .

[0073] [2-2. Manufacturing methods for press-molded products] The method for manufacturing the press-formed product 4 of the second embodiment is substantially the same as the method for manufacturing the press-formed product 1 of the first embodiment.

[0074] First, a blanking step and an intermediate forming step are performed, and an intermediate formed product 5 shown in Fig. 11 is formed from a flat workpiece 2. The intermediate formed product 5 includes first to fifth wall portions 41-45, first to fourth bent portions 46-49, an excess metal portion 51, and first to fourth through portions 52-55.

[0075] The excess metal portion 51 is provided at an end portion of the intermediate molded product 5. The excess metal portion 51 is continuous with each of the first to fifth wall portions 41 to 45 and the first to fourth bent portions 46 to 49. A boundary line Z1 between the first wall portion 41 and the excess metal portion 51, a boundary line Z3 between the third wall portion 43 and the excess metal portion 51, and a boundary line Z5 between the fifth wall portion 45 and the excess metal portion 51 are parallel to each other. A boundary line Z2 between the second wall portion 42 and the excess metal portion 51, and a boundary line Z4 between the fourth wall portion 44 and the excess metal portion 51 are parallel to each other. The boundary line Z2 between the second wall portion 42 and the excess metal portion 51 intersects with each of the boundary line Z1 between the first wall portion 41 and the excess metal portion 51 and the boundary line Z3 between the third wall portion 43 and the excess metal portion 51. A boundary line Z4 between the fourth wall portion 44 and the excess pad portion 51 intersects with a boundary line Z3 between the third wall portion 43 and the excess pad portion 51 and a boundary line Z5 between the fifth wall portion 45 and the excess pad portion 51.

[0076] Each of the first to fourth through-holes 52 to 55 has substantially the same configuration as the through-hole 25 of the first embodiment. However, the first through-hole 52 is located at a position where a boundary line Z2 between the second wall portion 42 and the excess pad portion 51 intersects with the first bent portion 46. The second through-hole 53 is located at a position where a boundary line Z3 between the third wall portion 43 and the excess pad portion 51 intersects with the second bent portion 47. The third through-hole 54 is located at a position where a boundary line Z4 between the fourth wall portion 44 and the excess pad portion 51 intersects with the third bent portion 48. The fourth through-hole 55 is located at a position where a boundary line Z5 between the fifth wall portion 45 and the excess pad portion 51 intersects with the fourth bent portion 49.

[0077] The position where the boundary line Z2 between the second wall portion 42 and the excess metal portion 51 intersects with the first bent portion 46 generally coincides with the position where the boundary line Z1 between the first wall portion 41 and the excess metal portion 51 and the boundary line Z2 between the second wall portion 42 and the excess metal portion 51 intersect with each other. The position where the boundary line Z3 between the third wall portion 43 and the excess metal portion 51 intersects with the second bent portion 47 generally coincides with the position where the boundary line Z2 between the second wall portion 42 and the excess metal portion 51 and the boundary line Z3 between the third wall portion 43 and the excess metal portion 51 intersect with each other. The position where the boundary line Z4 between the fourth wall portion 44 and the excess metal portion 51 intersects with the third bent portion 48 generally coincides with the position where the boundary line Z3 between the third wall portion 43 and the excess metal portion 51 and the boundary line Z4 between the fourth wall portion 44 and the excess metal portion 51 intersect with each other. The position where the boundary line Z5 between the fifth wall portion 45 and the excess material portion 51 intersects with the fourth bent portion 49 roughly coincides with the position where the boundary line Z4 between the fourth wall portion 44 and the excess material portion 51 and the boundary line Z5 between the fifth wall portion 45 and the excess material portion 51 intersect with each other.

[0078] After the intermediate molding process, a trimming process is performed. In the trimming process, the intermediate molded product 5 obtained by the intermediate molding process is subjected to a trimming process. Specifically, as shown by the white arrow in FIG. 11, the intermediate molded product 5 is cut along a boundary line Z1 between the first wall portion 41 and the excess part 51 from a direction intersecting with the first wall portion 41 (a direction perpendicular to the first wall portion 41 in this embodiment). The intermediate molded product 5 is cut along a boundary line Z2 between the second wall portion 42 and the excess part 51 from a direction intersecting with the second wall portion 42 (a direction perpendicular to the second wall portion 42 in this embodiment). The intermediate molded product 5 is cut along a boundary line Z3 between the third wall portion 43 and the excess part 51 from a direction intersecting with the third wall portion 43 (a direction perpendicular to the third wall portion 43 in this embodiment). The intermediate molded product 5 is cut from a direction intersecting with the fourth wall portion 44 (a direction perpendicular to the fourth wall portion 44 in this embodiment) along a boundary line Z4 between the fourth wall portion 44 and the excess pad portion 51. The intermediate molded product 5 is cut from a direction intersecting with the fifth wall portion 45 (a direction perpendicular to the fifth wall portion 45 in this embodiment) along a boundary line Z5 between the fifth wall portion 45 and the excess pad portion 51. The above-mentioned boundaries Z1 to Z5 correspond to so-called trim lines.

[0079] In the trimming step, excess metal portion 51 is removed from intermediate product 5, and press-formed product 4 shown in FIG. 10 is obtained.

[0080] [2-3. Effects] According to the second embodiment described above in detail, the same effects as those of (1a) to (1f) and (1h) above can be obtained.

[0081] 3. Other embodiments Although the embodiments of the present disclosure have been described above, it goes without saying that the present disclosure is not limited to the above-described embodiments and can take various forms.

[0082] (3a) In the manufacturing method of the press-molded products 1 and 4 of the above embodiments, in the blanking step, the through-holes 25, 52 to 55 are formed in the workpiece 2. When the through-holes are formed in the workpiece in this manner, the size of the through-holes is not particularly limited.

[0083] However, it is preferable that the through-hole is large within a range that does not adversely affect the performance such as the strength in the press molding of the finished product. For example, the through-hole may be large enough to overlap the first bent part in the entire bending direction of the first bent part in the intermediate molded product as in the above embodiment, and further overlap at least one of a part of the first wall part and a part of the second wall part. If the through-hole is large, even if an intermediate molded product having an outer shape slightly deviated from the design is molded in the intermediate molding process and the position where the trim blade passes through the intermediate molded product in the subsequent trimming process is slightly deviated from the position set as the trim line, it is possible to prevent the position where the trim blade passes through the intermediate molded product from deviating from the through-hole. In other words, it is possible to prevent the intermediate molded product from being cut along a line deviating from the through-hole. Therefore, it is possible to further easily obtain the effect of (1d) above.

[0084] On the other hand, when a through-hole is formed in the workpiece, there is a possibility that deformation of the through-hole or cracks originating from the through-hole may occur when the workpiece is subsequently bent. For example, in the first embodiment, when the workpiece 2 is bent along the boundary line X1 between the first forming portion 21 and the second forming portion 22 in the first bending process in the intermediate forming step S2, the through-hole 25 is pulled in the bending direction D of the first bending portion 14. This may cause the through-hole 25 to extend in the bending direction D of the first bending portion 14, or the intermediate molded product 3 to crack from the through-hole 25 in a direction perpendicular to the bending direction D of the first bending portion 14. From the viewpoint of suppressing deformation of the through-hole or cracks originating from the through-hole when the workpiece is bent, it is preferable that the through-hole is not too large.

[0085] (3b) When a through-hole is formed in the workpiece as in the above embodiment, the shape of the through-hole is not particularly limited. For example, the through-hole may be a round hole as in the above embodiment, or a square hole. For example, when the through-hole is a square hole, it is easier to suppress the deformation of the through-hole when the workpiece is bent, compared to when the through-hole is a round hole. Also, for example, the through-hole may be shaped to extend along the outer shape of the finished press-molded product.

[0086] As an example, FIG. 12A shows an intermediate product 3A in which a through-hole 25A is a triangular hole, which is a type of rectangular hole. The intermediate product 3A has the same configuration as the intermediate product 3 of the first embodiment, except for the shape of the through-hole 25A. In the intermediate product 3A, the corner of the through-hole 25A is preferably oriented toward the excess pad 31. According to this configuration, since the corner of the through-hole 25A that is relatively likely to become the starting point of a crack is oriented toward the excess pad 31, even if a crack originating from the through-hole 25A occurs when the workpiece is bent, the crack is likely to occur within the excess pad 31. Therefore, it is possible to further suppress the occurrence of cracks in the finished press-formed product 1.

[0087] (3c) In the above embodiment and the example shown in Fig. 12A, the through-holes 25, 25A, 52-55 are holes penetrating the workpiece 2 in the thickness direction. However, the through-holes do not necessarily have to be holes, and may be cutouts penetrating the workpiece 2 in the thickness direction, such as the through-hole 25B shown in Fig. 12B. Fig. 12B shows an intermediate molded product 3B in which a through-hole 25B is formed, as an example.

[0088] (3d) In the first embodiment, a plurality of processes are performed simultaneously in each of the blanking process S1, the intermediate forming process S2, and the first trimming process S3. However, the plurality of processes included in each of the processes S1 to S3 do not necessarily have to be performed simultaneously, and may be performed, for example, in sequence. In this case, the order of the plurality of processes is not particularly limited.

[0089] (3e) In the first embodiment, the through-hole forming process is performed in the blanking step S1. However, the through-hole forming process does not necessarily have to be performed in the blanking step S1, and may be performed in the subsequent intermediate molding step S2, for example.

[0090] (3f) In the first embodiment, the second trimming step S4 is performed after the first trimming step S3, but the order of the first trimming step S3 and the second trimming step S4 is not particularly limited. For example, the second trimming step S4 may be performed before the first trimming step S3. That is, the intermediate molded product 3 may be cut, for example, along the boundary line Y1 between the first wall portion 11 and the excess material portion 31, and then cut along the boundary line Y2 between the second wall portion 12 and the excess material portion 31, thereby removing the excess material portion 31 from the intermediate molded product 3. Also, for example, the first trimming step S3 and the second trimming step S4 may be performed as one step rather than separate steps.

[0091] (3g) In the first cutting process in the first trimming step S3 in the first embodiment, the intermediate molded product 3 is cut from a direction intersecting with the second wall portion 12 along the boundary line Y2 between the second wall portion 12 and the excess material portion 31. This first cutting process may be realized, for example, by a device configured to displace a trimming blade in a direction intersecting with the second wall portion 12 by a cam mechanism, or may be realized by a person adjusting the orientation of the intermediate molded product 3 so that the second wall portion 12 is oriented in an orientation intersecting with the displacement direction of the trimming blade. The same applies to the second cutting process and the second trimming step S4 in the first embodiment, and each cutting process in the trimming step in the second embodiment.

[0092] (3h) The function of one component in the above embodiments may be distributed among multiple components, or the functions of multiple components may be integrated into 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.

[0093] [Technical idea disclosed in this specification] [Item 1] A manufacturing method of a press-molded product having a first wall portion, a second wall portion intersecting the first wall portion, and a bent portion connecting the first wall portion and the second wall portion, forming a through-portion in a workpiece that passes through the workpiece; bending the workpiece in which the through portion is formed to form an intermediate formed product in which the first wall portion, the second wall portion, and the bent portion are formed; removing excess portions, which are portions of the intermediate product that are continuous with the first wall portion, the second wall portion, and the bent portion, from the intermediate product to obtain the press-formed product; Equipped with the through portion is formed in the workpiece so that the through portion is located at a position where a boundary line between the second wall portion and the excess portion intersects with the bent portion in the intermediate molded product; A method for manufacturing a press-molded product, wherein the intermediate molded product is cut along a boundary line between the first wall portion and the excess metal portion from a direction intersecting with the first wall portion, and cut along a boundary line between the second wall portion and the excess metal portion from a direction intersecting with the second wall portion, thereby removing the excess metal portion from the intermediate molded product.

[0094] [Item 2] A method for producing a press-molded product according to item 1, A method for manufacturing a press-molded product, wherein the through portion is formed in the workpiece so that the through portion overlaps the bent portion over the entire bending direction of the bent portion in the intermediate molded product.

[0095] [Item 3] A method for producing a press-molded product according to item 1 or 2, A method for manufacturing a press-molded product, wherein at least a portion of the second wall portion is curved so as to bulge toward the first wall portion.

[0096] [Item 4] A method for producing a press-molded product according to any one of items 1 to 3, a manufacturing method for a press-molded product, wherein the intermediate molded product is cut along a boundary line between the first wall portion and the excess material portion from a direction perpendicular to the first wall portion, and cut along a boundary line between the second wall portion and the excess material portion from a direction perpendicular to the second wall portion.

[0097] [Item 5] A method for producing a press-molded product according to any one of items 1 to 4, A method for manufacturing a press-formed product, wherein the workpiece is made of high-tensile steel. [Explanation of symbols]

[0098] 1...press-formed product, 11...first wall portion, 12...second wall portion, 13...third wall portion, 14...first bent portion, 15...second bent portion, 2...workpiece, 21...first formed portion, 22...second formed portion, 23...third formed portion, 24...excess material portion, 25...penetration portion, 3...intermediate formed product, 31...excess material portion.

Claims

1. A manufacturing method of a press-formed product having a first wall portion, a second wall portion intersecting the first wall portion, and a bent portion connecting the first wall portion and the second wall portion, forming a through-portion in a workpiece that passes through the workpiece; bending the workpiece in which the through-hole is formed to form an intermediate product in which the first wall portion, the second wall portion, and the bent portion are formed; removing excess portions, which are portions of the intermediate product that are continuous with the first wall portion, the second wall portion, and the bent portion, from the intermediate product to obtain the press-formed product; Equipped with the through portion is formed in the workpiece so that the through portion is located at a position where a boundary line between the second wall portion and the excess portion intersects with the bent portion in the intermediate molded product; A manufacturing method for a press-molded product, in which the intermediate molded product is cut along a boundary line between the first wall portion and the excess metal portion from a first direction that intersects with the first wall portion, and cut along the boundary line between the second wall portion and the excess metal portion from a second direction that intersects with the second wall portion and is a direction different from the first direction, thereby removing the excess metal portion from the intermediate molded product.

2. A method for producing a press-molded product according to claim 1, A method for manufacturing a press-molded product, wherein the through portion is formed in the workpiece so that the through portion overlaps the bent portion over the entire bending direction of the bent portion in the intermediate molded product.

3. A method for producing a press-molded product according to claim 1 or 2, A method for manufacturing a press-molded product, wherein at least a portion of the second wall portion is curved so as to bulge toward the first wall portion.

4. A method for producing a press-molded product according to claim 1 or 2, A manufacturing method for a press-molded product, wherein the intermediate molded product is cut along a boundary line between the first wall portion and the excess material portion from the first direction perpendicular to the first wall portion, and cut along a boundary line between the second wall portion and the excess material portion from the second direction perpendicular to the second wall portion.

5. A method for producing a press-molded product according to claim 1 or 2, A method for manufacturing a press-formed product, wherein the workpiece is made of high-tensile steel.

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