Press-molded product for vehicles and method for producing the press-molded product

Abstract

A press-formed product of the present disclosure comprises a plate-shaped portion (12), a wall (14), and a flange (16). The wall (14) has at least one curved surface with an arcuate cross-sectional shape that bulges radially outward in a cross-section along the plate-shaped portion (12). The at least one curved surface (24) comprises a first curved surface (34) and a second curved surface (36). The second curved surface (36) is a portion that is closer to the flange (16) than the first curved surface (34). A radius of curvature of the second curved surface (36) in cross-section is smaller than a radius of curvature of the first curved surface (34) in cross-section.

Description

BACKGROUND

[0001] The present disclosure relates to a press-molded product for vehicles and a method for producing the press-molded product, and more particularly to a method for improving its appearance.

[0002] Japanese Patent No. 5569609 discloses a press-molding method that can prevent wrinkling in a press-molded product. SUMMARY

[0003] The inventor of the present disclosure has investigated techniques for improving the appearance of a press-molded product, such as wrinkle reduction techniques. The press-molded product includes a plate-shaped portion, a wall, a flange, and a curved surface with an arcuate cross-sectional shape that bulges radially outward in a cross-section along the plate-shaped portion. As a result of the investigation, the inventor of the present disclosure found that wrinkles were easily formed on the curved surface in a region closer to the flange of the press-molded product.

[0004] In one aspect of the present disclosure, it is desirable to reduce wrinkling on the curved surface in the region closer to the flange of the press-formed product.

[0005] One aspect of the present disclosure is a press-formed product including a plate-shaped portion, a wall, and a flange. The wall has a plate shape and extends from the plate-shaped portion in a direction crossing the plate-shaped portion. The flange has a plate shape and extends from an edge of the wall. The wall includes at least one curved surface having an arcuate cross-sectional shape that bulges radially outward in a cross-section along the plate-shaped portion. The at least one curved surface includes a first curved surface and a second curved surface. The second curved surface is a portion closer to the flange than the first curved surface. A radius of curvature of the second curved surface in cross-section is smaller than a radius of curvature of the first curved surface in cross-section.

[0006] In this configuration, the circumferential length of the wall in the area closer to the flange is longer than the circumferential length of the wall in the area farther from the flange. Thus, during press forming, the material flowing from the flange into the wall is distributed in the circumferential direction, preventing the material from wrinkling. This results in an anti-wrinkling effect. This prevents wrinkling on the curved surface in the area closer to the flange.

[0007] In one aspect of the present disclosure, the wall may further include a stepped surface formed between the first curved surface and the second curved surface. The second curved surface may be located radially outward from the first curved surface.

[0008] In this configuration, a length of an outer surface of the wall in its span direction is longer by an amount equal to the stepped surface than a length of an outer surface of the wall in its span direction without the stepped surface. This allows the material flowing from the flange to be distributed in the span direction as well, enhancing the anti-wrinkle effect achieved by the material. This allows wrinkling on the curved surface to be further reduced in the area closer to the flange.

[0009] In one aspect of the present disclosure, the wall may include a plurality of stepped surfaces. In this configuration, a length of an outer surface of the wall in the spanwise direction is longer by an amount of the stepped surfaces than the length of the outer surface of the wall in the spanwise direction with a stepped surface. This facilitates the distribution of the material flowing from the flange into the wall, further enhancing the anti-wrinkling effect achieved by the material. This may further reduce wrinkling on the curved surface in the region closer to the flange.

[0010] In one aspect of the present disclosure, the press-formed product may be a body component of a motor vehicle. This configuration further reduces wrinkling on the curved surface in the region closer to the flange of the vehicle body component.

[0011] In one aspect of the present disclosure, the compression-molded product may have a bag shape with a recess. The wall may have a plurality of curved surfaces. The wall may further include a flat portion having a flat plate shape connecting the plurality of curved surfaces. This configuration reduces wrinkling on the curved surface in the area closer to the flange of the bag-shaped compression-molded product.

[0012] One aspect of the present disclosure may be a method for producing a press-molded product for obtaining a press-molded product having a specific target shape using a first and a second die. The above-described press-molded product is obtained according to the method. The first and second dies each have a first molding portion, a second molding portion, and a third molding portion. The first molding portion is a portion for forming the plate-shaped portion. The second molding portion is a portion for forming the wall. The third molding portion is a portion for forming the at least one curved surface.The method for producing the press-molded product comprises: a blank is placed between the first die and the second die which are separated from each other, and the first die and the second die are brought closer to each other with the blank placed between the first die and the second die.

[0013] With this configuration, it is possible to produce the press-molded product described in detail above. That is, a press-molded product with reduced wrinkling can be obtained. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Some embodiments of the present disclosure will now be described by way of example with reference to the accompanying drawings, in which: Fig. 1 is a perspective view of a press-molded product of a first embodiment, Fig. 2A a plan view of the Fig. 1 shown molded product, Fig. 2B a cross-sectional view along the line IIB-IIB in Fig. 2A, Fig. 3A is a plan view conceptually showing a difference in the radii of curvature and a difference in the circumferential lengths in a corner of the Fig. 1 shown molded product, Fig. 3B is a cross-sectional view along the line IIIB-IIIB in Fig. 3A, Fig. 4 a cross-sectional view of a press molding device for producing the Fig. 1 shown molded product, Fig. 5 a perspective view of a through the in Fig. 4 shown press molding device formed intermediate product, Fig. 6A is a plan view of a press-molded product of a second embodiment, Fig. 6B is a cross-sectional view along the line VIB-VIB in Fig. 6A and Fig. 7 is a perspective view of a press-molded product of a third embodiment. DETAILED DESCRIPTION OF EMBODIMENTS [1. First Embodiment] [1-1. Configuration of a Press-Molded Product] <Overview of the Press-Molded Product>

[0015] The first embodiment relates to a press-molded product and a method for producing the press-molded product.

[0016] Fig. 1 shows a perspective view of a press-molded product 10 formed by the method for producing the press-molded product according to the first embodiment.

[0017] The press-molded product 10 serves as a component of an automobile body after undergoing a drawing process according to the manufacturing method of the first embodiment and subsequent necessary additional processes (e.g., a trimming process and a bending process). The press-molded product 10 serves, for example, as a rear floor with space for accommodating a spare tire. In addition to the spare tire, the space of the press-molded product 10 can also accommodate a tool, a safety vest, a charging cable (e.g., for electric vehicles), etc. The press-molded product 10 and its manufacturing method can be applied to various other components and products, including, but not limited to, the rear floor.

[0018] The press-formed product 10 is obtained by press-forming (drawing), including drawing and bending, a blank 50 made of steel sheet. The blank 50 used for the press-formed product 10 may be, for example, a steel sheet with a zinc alloy coating. The blank 50 may have a sheet thickness of 0.6 mm to 1.4 mm. In the first embodiment, the blank 50 has a sheet thickness of 0.6 mm. <Gesamtform des pressgeformten Produkts>

[0019] The compression-molded product 10 has a pouch shape with depth. The pouch shape is a shape that can accommodate an object. The term "accommodate" here means that the object is held by a bottom wall and a side wall. In other words, the pouch shape refers to a configuration that has a bottom wall and one or more side walls.

[0020] The bag-shaped portion of the press-molded product 10 (a portion other than a flange 16, as described below) has dimensions of, for example, about 600 mm in width, about 200 mm in horizontal depth, and about 180 mm in vertical depth. Hereinafter, a direction along the vertical depth of the press-molded product 10 is referred to as the depth direction X (see also Fig. 1). The vertical depth of the press-formed product 10 is 80 mm or more. The press-forming process in which the blank 50 is drawn into a bag shape with depth is also called "deep drawing."

[0021] The press-formed product 10 has a top plate 12, a vertical wall 14 and the flange 16. In Fig. 1, the upper plate 12 is shown for illustrative purposes as an upper portion of the press-formed product 10; however, the press-formed product 10 is used in a posture in which the top and bottom of Fig. 1 are reversed. Therefore, the upper plate 12 can be understood as a floor wall, considering its use state. In the first embodiment, the space enclosed by the upper plate 12 and the vertical wall 14 is a space for accommodating a spare tire, a tool, a safety vest, a charging cable, etc.

[0022] The top plate 12 is a substantially flat plate. The top plate 12 has a substantially rectangular shape in plan view, with two adjacent corners rounded to form the top plate curves 18, as described below. However, the top plate 12 may generally have another substantially polygonal shape in plan view. The top plate 12 has two top plate curves 18 along its circumference. In the first embodiment, the top plate curve 18 forms an arc of a perfect circle. However, the top plate curve 18 may form an arc of an oval or a compound curve, etc. The top plate 12 may have a raised portion, a depressed portion, a hole, and the like, as required. Hereinafter, a flat surface covering a large area of the top plate 12 may be simply referred to as "top plate 12."

[0023] The vertical wall 14 is a portion extending from the upper plate 12 in a direction that crosses the upper plate 12. The vertical wall 14 has a plate shape. In this embodiment, the vertical wall 14 extends from a portion of the periphery of the upper plate 12, which portion includes the two upper plate curves 18. Hereinafter, a direction in which the vertical wall 14 extends is referred to as an extension direction Y, as shown in Fig. 2B. In this embodiment, the extension direction Y is inclined with respect to the depth direction X. When the vertical wall 14 is not inclined with respect to the depth direction X, the extension direction Y is the same as the depth direction X. The vertical wall 14 is inclined to extend outward from the top plate 12.

[0024] The flange 16 extends from the edge of the vertical wall 14. In other words, the flange 16 extends outward from the edge of the vertical wall 14. The flange 16 extends substantially parallel to the top plate 12. The flange 16 has a plate shape. The flange 16 has a substantially partially annular shape in its plan view.

[0025] The vertical wall 14 has three flat sections 20 and two corner sections 22. Each corner section 22 is a ribbon-shaped region extending from the top panel curvature 18 with a substantially constant width. Each flat section 20 connects a plurality of curved surfaces 24, which are described further below. Each flat section 20 has a linear cross-sectional shape in cross-section along the top panel 12. Each flat section 20 is a section of the vertical wall 14 except for the corner sections 22.

[0026] Since the press-molded product 10 of the first embodiment is symmetrical, as shown in Fig. 1, a corner section 22 is described below with the center of gravity on only one side. However, the molded product 10 is not necessarily symmetrical.

[0027] The corner section 22 has a first region 30, which is closer to the upper plate 12, and a second region 32, which is closer to the flange 16. The first region 30 is connected to the curvature 18 of the upper plate 12, and the second region 32 is connected to the flange 16. In other words, the first region 30 is arranged adjacent to the upper plate 12, and the second region 32 is arranged adjacent to the flange 16. The first region 30 and the second region 32 are arranged side by side along the extension direction Y, with a stepped surface 38 described below therebetween. In the Fig. 1, approximately 50% of the upper section in the depth direction X forms the first region 30 and approximately 50% of the lower section forms the second region 32.

[0028] The curved surface 24 has a first curved surface 34 and a second curved surface 36.

[0029] The first curved surface 34 is contained within the first region 30. The first curved surface 34 has a first arcuate cross-section that curves radially outward in a cross-section along the top plate 12. The second curved surface 36 is contained within the second region 32. The second curved surface 36 has a second arcuate cross-section that curves radially outward in a cross-section along the top plate 12.

[0030] The cross section along the upper plate 12 is a cross section perpendicular to the depth direction X. In the first embodiment, the shapes of the first arcuate cross section and the second arcuate cross section are constant at any position along the depth direction X. The shapes of the first arcuate cross section and the second arcuate cross section are not limited to the arcuate shapes of perfect circles and may include other cross-sectional shapes such as outwardly curved oval arcs and compound curves.

[0031] The vertical wall 14 has the stepped surface 38 formed between the first curved surface 34 and the second curved surface 36. The stepped surface 38 is a flat surface connecting the first curved surface 34 and the second curved surface 36 and extending substantially parallel to the top plate 12. In the first embodiment, the stepped surface 38 is formed at an intermediate position of the corner portion 22 along the depth direction X.

[0032] The second curved surface 36 is disposed radially outward of the first curved surface 34. As used herein, the term "radial" refers to a radial direction of the arcs of the first arcuate cross-section and the second arcuate cross-section. As in Fig. 2B, when the corner portion 22 is viewed along the extension direction Y, the second curved surface 36 projects so as to be located outside the first curved surface 34 (ie, to the right in Fig. 2B).

[0033] The radius of curvature R2 (described in detail below) of the second curved surface 36 in the cross-section along the top plate 12 is smaller than the radius of curvature R1 of the first curved surface 34 in the cross-section along the top plate 12. In the first embodiment, R1 and R2 are constant at any position along the depth direction X. However, the radii of curvature of the first curved surface 34 and the second curved surface 36 are not necessarily constant and may vary along the depth direction X. In the first embodiment, R1 is 200 mm and R2 is 100 mm. However, R1 and R2 are not limited to these values and can take any values, provided R2 is smaller than R1. [1-2. Press molding device]

[0034] Fig. 4 is a cross-sectional view of a die set of a press-molding apparatus for forming the press-molded product 10. The die set of the press-molding apparatus includes a die 60, a punch 62, and a blank holder 64. The die 60 and the punch 62 are configured to be displaceable relative to each other in the depth direction X of the press-molded product 10 by means of a drive mechanism not shown. For example, the die 60 may be displaced in the depth direction X, or the punch 62 may be displaced in the depth direction X, or both the die 60 and the punch 62 may be displaced in the depth direction X. In the first embodiment, the die 60 is displaced in the depth direction X. The blank holder 64 is configured to be displaceable in the depth direction X in conjunction with or independently of the die 60.

[0035] The die 60 and the punch 62 cooperate to perform the compression molding. The die 60 and the punch 62 are spaced apart and face each other. The die 60 has a concave shape and includes a die bore 66 into which the top of the punch 62 is inserted. The punch 62 has a convex shape.

[0036] The die 60 and the punch 62 each have a shape corresponding to the shape of the press-formed product 10. Specifically, the die 60 has a first molding section 70a, a second molding section 72a, and a third molding section 74a. The punch 62 has a first molding section 70b, a second molding section 72b, and a third molding section 74b. The first molding sections 70a, 70b serve to form the top plate 12. The second molding sections 72a, 72b serve to form the vertical wall 14. The third molding sections 74a, 74b serve to form the first curved surface 34 and the second curved surface 36.

[0037] The blank holder 64 cooperates with the die 60 to hold and secure the blank 50. The blank holder 64 faces the die 60. A through hole corresponding to the punch 62 is formed in the center of the blank holder 64. [1-3. Method for producing a press-molded product]

[0038] Next, a method for manufacturing the press-molded product 10 will be described. In the first embodiment, the following press-molding is performed to manufacture the press-molded product 10.

[0039] In this first embodiment, press forming (the molding method described below) is performed in a single step. The inventor confirmed through simulation analysis that wrinkles and cracks were reduced even when press forming was performed in a single step. However, press forming may be performed in multiple steps instead of a single step. In the first embodiment, press forming is performed by lowering the die 60. However, the punch 62 may be moved upward, or both the die 60 and the punch 62 may be shifted.

[0040] The method for producing the press-formed product 10 includes a placing step of placing the blank 50 between the die 60 and the punch 62 at a distance from each other, and a forming step of bringing the die 60 and the punch 62 closer together (e.g., snapping them together), placing the blank 50 between the die 60 and the punch 62.

[0041] First, in the placing step, the blank 50 is mounted on the upper surface of the blank holder 64, wherein the blank 50 is placed between the die 60 and the punch 62, which are spaced apart from each other.

[0042] Subsequently, in the forming step, the die 60 is lowered and brought relatively closer to the blank holder 64, thereby fixing the blank 50 in a state of being held between the blank holder 64 and the die 60.

[0043] The die 60 is further lowered, with the die 60 and blank holder 64 being lowered integrally with the blank 50 held therebetween. As the die 60 is further lowered, the first forming portion 70b of the punch 62 comes into contact with the blank 50. As the die 60 is further lowered, the blank 50 is pressed into the die bore 66 by the punch 62. When the die 60 reaches the bottom dead center, the upper plate 12 is formed by the first forming portions 70a, 70b. At this time, the vertical wall 14 is formed by the second forming portions 72a, 72b, and the first curved surface 34 and the second curved surface 36 are formed by the third forming portions 74a, 74b. The flange 16 is formed by the blank holder 64 and the die 60.

[0044] In this way, a Fig. 5 is formed. The intermediate product 52 is formed into the press-molded product 10 by undergoing subsequent steps such as a trimming process and / or a bending process, etc., in which, for example, a bent portion for reinforcing the flange 16 is formed and / or a hole for attaching the press-molded product 10 at a specific location is formed. [1-4. Difference in radii of curvature and difference in circumferential lengths in the corner section]

[0045] The difference in the radii of curvature and the difference in the circumferential lengths in the corner section 22 are described below using the Fig. 3A and Fig. 3B; however, first, a concept of the “mean angle”, which is the focus of the description, is explained.

[0046] During press forming, the material forming the blank 50 is stretched such that the material in a portion corresponding to the flange 16 flows into a portion corresponding to the vertical wall 14 along the extension direction Y. This movement of the material is conceptually described by focusing on the material in a target portion. The target portion is an area of the blank 50 that forms both a portion of the flange 16 and a portion of the vertical wall 14 near the corner portion 22. The target portion has a substantially partially annular shape in the blank 50. In the following description, the extension direction Y is also referred to as the "axial direction."

[0047] During press forming, the material of the target portion of the blank 50 flows from the portion corresponding to the flange 16 to the portion corresponding to the vertical wall 14, specifically to a region having the same central angle as the target portion. The material moves within a band-shaped region along the axial direction.

[0048] In the Fig. 3A, the same-average-angle region is a portion (e.g., the first curved surface 34) obtained by stacking fan-shaped arcs located at a certain distance from a center point O1 along the extending direction Y at arbitrary positions in the extending direction Y. However, the same-average-angle region includes not only the fan-shaped arcs but also a portion formed from the target portion (e.g., a continuous portion that is a combination of the second curved surface 36 and two flat surfaces 40). In other words, the same-average-angle region is a band-shaped portion extending from the flange 16 to the top plate 12 in the corner portion 22. In the first embodiment, the same-average-angle region is a band-shaped portion Z between two dashed lines in the corner portion 22 (see Fig. 1).

[0049] Based on the above, a region of the corner portion 22 to be considered for wrinkle reduction can be defined as the region having the same average angle, including but not limited to the curved surfaces such as the first curved surface 34 and the second curved surface 36.

[0050] Further with reference to the Fig. 3A and Fig. 3B, the difference in the radii of curvature in the corner section 22 is described. Fig. 3A is a plan view of the corner portion 22, which is a model assuming that the outer surface of the corner portion 22 other than the stepped surface 38 extends in the depth direction X. The difference in the radii of curvature herein is a difference between a radius of curvature R1 of the first curved surface 34 and a radius of curvature R2 of the second curved surface 36. As described above, the radius of curvature R2 of the second curved surface 36 is set smaller than the radius of curvature R1 of the first curved surface 34.

[0051] The difference in the circumferential lengths due to the difference in the radii of curvature in the corner section 22 is a difference between a circumferential length L2 of the second region 32 and a circumferential length L1 of the first region 30.

[0052] As in Fig. As shown in Figure 3A, the first region 30 includes the first curved surface 34, which extends in cross-section over and forms a fan-shaped arc with a mean angle θ1 (e.g., 90 degrees) and a specified R1 (e.g., 200 mm). The center of the first curved surface 34 in the thus-defined first region 30 is indicated by O1.

[0053] In the Fig. In the model shown in Figure 3A, the first curved surface 34 coincides with the first region 30. Thus, the circumferential length L1 of the first region 30 is the same as the length of the arc that can be obtained by cutting the first curved surface 34 in a plane perpendicular to the depth direction X.

[0054] As in Fig. As shown in Figure 3A, the second region 32 includes the second curved surface 36, which extends in cross-section over and forms a fan-shaped arc with a mean angle θ2 (e.g., 90 degrees) and a specified R2 (e.g., 100 mm). The center of the second curved surface 36 in the thus-defined second region 32 is indicated by 02.

[0055] The second region 32 includes the two flat surfaces 40 arranged on both sides of the second curved surface 36, such that the second curved surface 36 is located therebetween in a circumferential direction. Therefore, the second region 32 is configured as a continuous section including the second curved surface 36 and the two flat surfaces 40.

[0056] Thus, the circumferential length L2 of the second region 32 is a total length of the arc and two lines obtained by intersecting the second curved surface 36 and the flat surfaces 40 in a plane perpendicular to the depth direction X.

[0057] As in Fig. As shown in Figure 3A, the first region 30 and the second region 32 have the same average angle θ1, and R2 is smaller than R1. Thus, the circumferential length L2 of the second region 32 is longer than the circumferential length L1 of the first region 30.

[0058] The difference in circumferential lengths between the first region 30 and the second region 32 was described by focusing on the corner section 22. However, by not focusing on the corner section 22, it is possible to focus on the entire press-formed product 10 and describe the difference in circumferential lengths between regions closer to the top plate 12 and closer to the flange 16 in the vertical wall 14.

[0059] Here, the differences in the radius of curvature and the circumferential length have been described in a hypothetical context, assuming that the outer surface of the corner portion 22 is not inclined with respect to the depth direction X. However, the relationship between the first region 30 and the second region 32 with respect to the difference in the radii of curvature and the difference in the circumferential length can also be applied to a case where the outer surface of the corner portion 22 is inclined with respect to the depth direction X. More specifically, in the corner portion 22, the circumferential length of the region closer to the flange 16 is longer than the circumferential length of the region closer to the top plate 12, while the radius of curvature in the region closer to the flange 16 is smaller than the radius of curvature in the region closer to the top plate 12.This characteristic configuration can also be applied to a case where the outer surface of the corner portion 22 is inclined with respect to the depth direction X in a similar manner. [1-5. Effects]

[0060] The inventor conducted simulations to evaluate the effectiveness of various test products, including the press-molded product 10 of the first embodiment.

[0061] First, the inventor proposed a primary test product in which the radius of curvature of the corner portion 22 was uniformly set to 100 mm as the target shape. As a result of simulation analysis of the primary test product, it was found that cracks could occur along a boundary between the top plate 12 and the corner portion 22 and near the boundary, i.e., a punching shoulder.

[0062] The inventor then proposed a secondary test product in which the radius of curvature of the corner portion 22 was uniformly set at 200 mm. As a result of the simulation analysis of the secondary test product, the possibility of cracks in the punching shoulder was reduced; however, it was found that wrinkles might occur in the second region 32 of the corner portion 22. The inventor assumed that the wrinkles were caused by material concentration in the second region 32 when material flows from the flange 16 to the vertical wall 14, and consequently by wrinkling of excess material in the second region 32.

[0063] Based on these experiments, the inventor focused on the differences in material movement between the region closer to the top plate 12 (i.e., the first region 30) and the region closer to the flange 16 in the corner portion 22 (i.e., the second region 32). The inventor then considered setting different radii of curvature between the first region 30 and the second region 32. Specifically, the inventor set R1 in the first region 30 to 200 mm to reduce cracks, and R2 in the second region 32 to 100 mm, as in the primary test product, to reduce wrinkles. The inventor also found that the circumferential length L2 of the second region 32 became longer than the circumferential length L1 of the first region 30 by adjusting the radii of curvature of the corner portion 22 as described above.

[0064] In this way, the inventor developed the press-molded product 10 of the embodiment. As a result of the simulation analysis of the press-molded product 10, the inventor confirmed that both the possibility of cracks in the punching shoulder and the formation of wrinkles in the second region 32 were reduced.

[0065] According to the first embodiment described in detail above, the following effects can be achieved. (1a) The press-formed product 10 of the first embodiment includes the corner portion 22 in which the circumferential length L2 in the circumferential direction of the second region 32 is longer than the circumferential length L1 in the circumferential direction of the first region 30. Therefore, during press-forming, the volume of the material occupying the second region 32 increases compared to that in the first region 30. Thus, the material flowing from the flange 16 to the vertical wall 14 is distributed circumferentially within the second region 32, thereby preventing wrinkling of the material. This can prevent wrinkling in the second region 32. (1b) In the press-formed product 10 of the first embodiment, the radius of curvature R1 of the first curved surface 34 is larger, and the radius of curvature R2 of the second curved surface 36 is smaller. This allows the material to flow more easily into the punch shoulder, thereby compensating for elongation and preventing the formation of cracks in the punch shoulder. (1c) In the press-formed product 10 of the first embodiment, R1 is 200 mm and R2 is 100 mm, which is smaller than R1. This simultaneously prevents both the formation of cracks in the punching shoulder and the formation of wrinkles in the second region 32 as described above. (1d) The press-molded product 10 of the first embodiment has the stepped surface 38 formed between the first curved surface 34 and the second curved surface 36. Thus, the length of the outer surface of the corner portion 22 in the extending direction Y is longer by the amount of the step than in the case where the corner portion 22 does not have the stepped surface 38. This allows the material flowing from the flange 16 to the corner portion 22 to be distributed evenly in the extending direction Y of the corner portion 221, thereby increasing the anti-wrinkle effect. As a result, the wrinkling in the second region 32 can be further prevented. (1e) In the press-formed product 10 of the first embodiment, the length of the outer surface of the corner portion 22 in the extending direction Y (ie, the length between the upper plate curve 18 and the flange 16 along the extending direction Y) is the longest when the circumferential centers of the corner portion 22 are connected along the extending direction Y. That is, the length of the outer surface of the corner portion 22 is at the position shown in the cross section of Fig. 2B. This effectively prevents the formation of wrinkles in the central portion of the second region 32 in the circumferential direction, where wrinkles are most likely to occur. (1f) In deep drawing, in order to achieve height in the depth direction X, it is generally necessary to divide the forming process into two or more steps to reduce wrinkles and cracks. In the method for producing the press-formed product 10 of the first embodiment, the press-formed product 10, in which fewer wrinkles and cracks are observed, can be formed in a single step. [1-6. Conceptual agreement]

[0066] The top plate 12 in the first embodiment corresponds to an example of the plate-shaped portion in the present disclosure, and the vertical wall 14 corresponds to an example of the wall in the present disclosure. The die 60 in this embodiment corresponds to an example of the first die in the present disclosure, and the punch 62 corresponds to an example of the second die in the present disclosure. [2. Second Embodiment][2-1. Configuration of a Press-Molded Product]

[0067] In the second embodiment, descriptions of elements similar to those in the first embodiment are omitted by referring to the same numbers and names, while elements different from the first embodiment are described in detail.

[0068] The press-molded product 10 of the first embodiment has a stepped surface 38. In contrast, a Fig. 6A and Fig. 6B, the press-molded product 100 of the second embodiment differs from the first embodiment in that the corner portion 22 has a plurality of stepped surfaces 106.

[0069] In the second embodiment, the second region 32 is divided into two subregions arranged side by side along the extension direction Y. Thus, the corner portion 22 of the second embodiment is divided into three subregions arranged side by side along the extension direction Y. The stepped surfaces 38 and 106 are each formed between adjacent subregions of the three subregions.

[0070] In the second embodiment, the second region 32 is divided into a second A region 102, which is closer to the top plate 12, and a second B region 104, which is closer to the flange 16. The second A region 102 is adjacent to the first region 30, with the stepped surface 38 disposed therebetween along the extension direction Y, and the second B region 104 is connected to the flange 16. The stepped surface 106 is formed between the second A region 102 and the second B region 104.

[0071] The second A-region 102 and the second B-region 104 have a second curved A-surface 108 and a second curved B-surface 110, respectively, which are similar to the first region 30 and the second region 32 in the first embodiment. The radius of curvature of the second curved B-surface 110 is smaller than the radius of curvature of the second curved A-surface 108. The second curved B-surface 110 is also located radially outward of the second curved A-surface 108.

[0072] Thus, the relationship between the second A region 102 and the second B region 104 of the second embodiment has similar features to the relationship between the first region 30 and the second region 32 of the first embodiment. That is, the radius of curvature of the region (the second B region 104) closer to the flange 16 in the second region 32 is smaller than a radius of curvature of the region (the second A region 102) closer to the top plate 12.

[0073] Thus, the relationship between the first region 30 and the second region 32 of the first embodiment with respect to the difference in radii of curvature and the difference in circumferential lengths can be applied to the relationship between the second A region 102 and the second B region 104 of the second embodiment with respect to the difference in radii of curvature and the difference in circumferential lengths. Thus, the circumferential length of the second B region 104 is longer than the circumferential length of the second A region 102.

[0074] In the second embodiment, the second region 32 is divided into the two sub-regions arranged side by side along the extension direction Y. However, the second region 32 may be divided into three or more sub-regions. In this case, of the two sub-regions of the second region 32 (ie, the second A region 102 and the second B region 104), the sub-region closer to the top plate 12 (the second A region 102) may be further divided into two sub-regions, and / or the sub-region closer to the flange 16 (the second B region 104) may be further divided into two sub-regions. These divisions have a similar feature to the relationship between the first region 30 and the second region 32 of the first embodiment.This means that among the subdivisions, the radius of curvature of a subdivision closer to the flange 16 is smaller than the radius of curvature of a subdivision closer to the upper plate 12. Thus, among the subdivisions, the circumferential length of the subdivision closer to the flange 16 can be longer than the circumferential length of the subdivision closer to the upper plate 12. [2-2. Effects] (2a) In the press-molded product 100 of the second embodiment, the number of stepped surfaces in the corner portion 22 is larger than that of the first embodiment. Thus, the length of the outer surface of the corner portion 22 in the extending direction Y is longer by the amount of the stepped surfaces than the length of the outer surface of the corner portion 22 in the first embodiment. This facilitates the distribution of the material flowing from the flange 16 into the corner portion 22, thereby further enhancing the anti-wrinkle effect achieved by the material. As a result, wrinkling in the region of the curved surface 24 closer to the flange 16 can be further reduced. (2b) In the press-molded product 100 of the second embodiment, the portions closer to the flange 16 have longer circumferential lengths than in the first embodiment. Thus, effects similar to those described in (1a) to (1f) can be achieved. [3. Third Embodiment][3-1. Configuration of a press-molded product]

[0075] In the third embodiment, descriptions of elements similar to those in the first and second embodiments are omitted by referring to the same numbers and labels, while elements different therefrom are described in detail.

[0076] In the press-molded products 10 and 100 of the first and second embodiments, the first region 30 and the second region 32 are arranged side by side with the stepped surface 38 arranged therebetween along the extending direction Y in the corner portion 22, as shown in FIGS. Fig. 1 and Fig. 6. The second A region 102 and the second B region 104 are arranged side by side with the stepped surface 106 therebetween. That is, in the press-formed products 10 and 100, the corner portion 22 has an uneven inclined surface with at least one stepped surface. Furthermore, in the press-formed products 10 and 100 of the first and second embodiments, the radius of curvature of each region in the curved surface 24 is constant at any position along the depth direction X.

[0077] In contrast, in the press-molded product 200 of the third embodiment, as shown in Fig. 7, the stepped surfaces 38 and 106 are not present. The inclined surface of the corner portion 22 is flat along the extension direction Y.

[0078] Furthermore, in the press-formed product 200 of the third embodiment, the radius of curvature of the curved surface 24 gradually decreases from the top plate 12 to the flange 16. That is, the radius of curvature of the curved surface 24 continuously varies and becomes smaller from the top plate 12 to the flange 16 along the depth direction X. Thus, the curved surface 24 has a tapered shape that tapers toward the flange 16. For example, the curved surface 24 may be a part of a conical surface having an apex near the flange 16.

[0079] The third embodiment also has the feature that the radius of curvature of a region closer to the flange 16 is smaller than the radius of curvature of a region closer to the top plate 12 in the corner portion 22, as in the first embodiment. Therefore, the relationship between the first region 30 and the second region 32 of the first embodiment in terms of the difference in radii of curvature and the difference in circumferential lengths can be applied to the corner portion 22 of the third embodiment, which does not have the stepped surfaces 38 and 106. Thus, the circumferential length of the region closer to the flange 16 in the corner portion 22 is longer than the circumferential length of the region closer to the top plate 12. [3-2. Effects]

[0080] In the press-formed product 200 of the third embodiment, the circumferential length of the region closer to the flange 16 is longer than the circumferential length of the region closer to the top plate 12 in the corner portion 22, as in the first and second embodiments. Therefore, the effects of (1a) to (1c) and (1e) to (1f) can be achieved. [4. Further embodiments]

[0081] The embodiments of the present disclosure have been described; however, it should be understood that the present disclosure is not limited to the above-described embodiments and that the present disclosure may be embodied in various forms.

[0082] A function of a single component in the aforementioned embodiments may be distributed among a plurality of components, and functions of a plurality of components may be achieved by a single component. Some of the configurations of the above-mentioned embodiments may be omitted. At least some of the configurations of the above-described embodiments may be added to or replaced by the configuration of another embodiment. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] JP 5569609

[0002]

Claims

[1] A compression-molded product comprising: a plate-shaped section (12), a wall (14) having a plate shape and extending from the plate-shaped portion (12) in a direction crossing the plate-shaped portion (12), and a flange (16) having a plate shape and extending from an edge of the wall (14), wherein the wall (14) has at least one curved surface (24) with an arcuate cross-sectional shape which bulges radially outward in a cross-section along the plate-shaped portion (12), wherein the at least one curved surface (24) comprises a first curved surface (34) and a second curved surface (36) that is closer to the flange (16) than the first curved surface, and wherein a radius of curvature of the second curved surface (36) in cross section is smaller than a radius of curvature of the first curved surface (34) in cross section. [2] A press-molded product according to claim 1, wherein the wall (14) further comprises a stepped surface (38) formed between the first curved surface (34) and the second curved surface (36), and wherein the second curved surface (36) is arranged radially outwardly of the first curved surface (34). [3] The compression molded product of claim 2, wherein the stepped surface (38) comprises a plurality of stepped surfaces and the wall (14) comprises the plurality of stepped surfaces. [4] A press-molded product according to any one of claims 1 to 3, wherein the press-molded product is a body component of a motor vehicle. [5] A press-molded product according to any one of claims 1 to 3, wherein the compression-molded product has a bag shape with a recess, wherein the at least one curved surface (24) has a plurality of curved surfaces and the wall (14) has the plurality of curved surfaces and wherein the wall (14) further comprises a flat portion (20) having a flat plate shape connecting the plurality of curved surfaces (24). [6] A method for producing a press-molded product for obtaining a press-molded product having a specified target shape using a first die (60) and a second die (62), wherein the molded product comprises: a plate-shaped section (12), a wall (14) having a plate shape and extending from the plate-shaped portion (12) in a direction crossing the plate-shaped portion (12), and a flange (16) having a plate shape and extending from an edge of the wall (14), wherein the wall (14) has at least one curved surface (24) with an arcuate cross-sectional shape which bulges radially outward in a cross-section along the plate-shaped portion (12), wherein the at least one curved surface (24) comprises a first curved surface (34) and a second curved surface (36) that is closer to the flange (16) than the first curved surface, and wherein a radius of curvature of the second curved surface (36) in cross section is smaller than a radius of curvature of the first curved surface (34) in cross section, the first die and the second die each comprise: a first molding section (70a, 70b) for molding the plate-shaped section (12), a second mold section (72a, 72b) for molding the wall (14) and a third molding section (74a, 74b) for molding the at least one curved surface, the method comprising: a blank (50) is placed between the first die (60) and the second die (62), which are spaced apart from each other, and the first die (60) and the second die (62) are brought closer together, whereby the blank (50) is placed between the first die (60) and the second die (62). [7] A method of manufacturing the press-molded product according to claim 6, wherein the wall (14) further comprises a stepped surface (38) formed between the first curved surface (34) and the second curved surface (36), and wherein the second curved surface (36) is disposed radially outwardly of the first curved surface (34). [8] A method of manufacturing the press-molded product according to claim 7, wherein the stepped surface (38) has a plurality of stepped surfaces and the wall (14) has the plurality of stepped surfaces. [9] A method for producing the press-molded product according to any one of claims 6 to 8, wherein the press-molded product is a body component of a motor vehicle.

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