Formed body, blank, method for manufacturing formed body, and mold

Abstract

To provide a molded article suppressed in break and wrinkle, to provide a blank for obtaining the molded article, to provide a manufacturing method of a molded article, and to provide a metal mold.SOLUTION: A molded article includes a first region part, a second region part and a third region part. A first ridge line, a second ridge line and a third ridge line are connected each other in corner parts. When a full length of a contour line formed by the first region part and the third region part is L1 (mm), and a full length of a contour line formed by the second region part and the third region part is L2 (mm), the following (formula 1) is satisfied. When a full length of an adjacent part along the extension direction of the third ridge line between the second region part and the third region part is L3 (mm), and a length of a non-contact part, obtained by subtracting the length of the third ridge line from the full length L3 is L4 (mm), the following (formula 2) is satisfied. L1>1.1×L2...(formula 1); 0.8×L3<L4<0.9×L3...(formula 2).SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a formed body obtained by forming a metal plate, a blank and a formed body manufacturing method for obtaining this formed body, and a mold used for this forming process.

Background Art

[0002] For example, in order to manufacture automobile parts, home appliance parts, etc., it is widely practiced to press a metal plate to obtain a formed body. These formed bodies often have a complex shape while being an integral object. For example, in an automobile dashboard, roughly speaking, there are some that are composed of three regions: a first region portion, a second region portion, and a third region portion. Here, the first region portion has a substantially rectangular flat plate shape. The second region portion is integrally continuous with one side edge of the first region portion and is inclined with respect to the first region portion in a side view. The third region portion is integrally continuous with the other side edge of the first region portion and is inclined in the same direction as the second region portion in a side view. The inclination directions of the second region portion and the third region portion are the same as each other. In addition, a wheelhouse, which is a concave portion for accommodating a part of an automobile tire, is formed in the third region portion.

[0003] When manufacturing such a formed body, first, a member having the first region portion and the second region portion and a member having the third region portion are prepared in advance, and then it is conceivable to join between these members by spot welding or the like. However, from the viewpoints of weight reduction and cost reduction, it is preferable to integrally form the first region portion to the third region portion by press-forming a metal plate.

[0004] However, when obtaining a formed body having such a complex shape by press-forming, local compressive stress acts on the third region portion, and as a result, wrinkles may occur. In order to suppress such quality defects, it is conceivable to perform drawing forming while applying tension to the third region portion. However, when using a metal sheet with low formability such as high-tensile steel sheet, depending on the shapes of the second region portion and the third region portion, there is a risk that the steel sheet may crack due to the tension applied in the drawing forming. Therefore, for example, as disclosed in Patent Document 1, even under forming conditions where it is difficult to apply drawing forming, techniques for efficiently forming while suppressing the occurrence of cracks have been studied.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, taking the example of the dash panel, for example, when forming a large wheelhouse on a high-tensile steel sheet with a tensile strength of 980 MPa or more, the forming difficulty becomes extremely high. In this case, even with the technique disclosed in Patent Document 1 above, it is not easy to stably obtain a formed body without causing cracks or wrinkles.

[0007] The present invention has been made in view of the above circumstances, and an object thereof is to provide a formed body in which cracks and wrinkles are suppressed. Another object of the present invention is also to provide a blank, a formed body manufacturing method, and a mold for obtaining the formed body.

Means for Solving the Problems

[0008] The present invention has been made in view of the above circumstances, and adopts the following aspects. (1) A formed body according to one aspect of the present invention has extends along a plane defined by an X-axis and a Y-axis that are orthogonal to each other, and a first ridge line and a second ridge line arranged with a corner therebetween wherein the first ridge line serves as an edge in the X-axis direction and the second ridge line serves as an edge in the Y-axis direction a first region portion, is arranged side by side with the first region portion across the first ridge line in the X-axis direction, and the edge in the X-axis direction is a second region portion that is integrally continuous with the first region portion via the first ridge line and is inclined to one side of the front and back surfaces of the first region portion, is arranged side by side with the first region portion across the second ridge line in the Y-axis direction, and the edge in the Y-axis direction is It is integrally connected to the first region part via the second ridge line, and is partially and integrally connected to the second region part via a third ridge line connected to the corner part. There is a third region part inclined to the one side with respect to the first region part, and includes the first ridge line, the second ridge line, and the third ridge line are connected to each other at the corner part, Let the total length of the outer contour line formed by the first region part and the third region part be L1 (mm), and let the total length of the outer contour line formed by the second region part and the third region part be L2 (mm). The following (Equation 1) is satisfied. when the side where the first region portion is located with respect to the second region portion is defined as the first side in the X-axis direction, and the side where the second region portion is located with respect to the first region portion is defined as the second side in the X-axis direction, the total length L1 is the sum of the length L11 in the Y-axis direction of the edge on the first side of the first region portion and the length L12 in the Y-axis direction of the edge on the first side of the third region portion, and the total length L2 is the sum of the length L21 in the Y-axis direction of the edge on the second side of the second region portion and the length L22 in the Y-axis direction of the edge on the second side of the third region portion, Let the total length of the adjacent part along the extension direction of the third ridge line between the second region part and the third region part be L3 (mm), and let the length of the non-joint part obtained by subtracting the length of the third ridge line from the total length L3 be L4 (mm). The following (Equation 2) is satisfied. L1 > 1.1×L2 ··· (Equation 1) 0.8×L3 < L4 < 0.9×L3 ··· (Equation 2)

[0009] Here, assume that the first region part is planar and is located on a plane formed by an X-axis and a Y-axis that are perpendicular to each other. Assume that the X-axis direction is the direction in which the first region part and the second region part are arranged, and the Y-axis direction is the direction in which the first region part and the third region part are arranged. In this case, the first region part and the second region part are arranged with the first ridge line sandwiched in the X-axis direction, the first region part and the third region part are arranged with the second ridge line sandwiched in the Y-axis direction, and the second region part and the third region part are arranged with the third ridge line and the non-joint part sandwiched in the Y-axis direction. Also, in the first region part, the first ridge line is the edge in the X-axis direction, and the second ridge line is the edge in the Y-axis direction. And in this case, the outer contour line formed by the first region portion and the third region portion (hereinafter referred to as the first outer contour line) is the outer contour line formed by the edge located on the first side in the X-axis direction among the two end edges in the X-axis direction of the first region portion and the third region portion. The outer contour line formed by the second region portion and the third region portion (hereinafter referred to as the second outer contour line) is the outer contour line formed by the edge located on the second side in the X-axis direction among the two end edges in the X-axis direction of the second region portion and the third region portion. Here, the first side in the X-axis direction is the side where the first region portion is located with respect to the second region portion, and the second side in the X-axis direction is the side where the second region portion is located with respect to the first region portion. The first ridge line is located on the second side with respect to the first region portion and on the first side with respect to the second region portion. Both the first outer contour line and the second outer contour line extend in the Y-axis direction. The total length L1 of the first outer contour line is the length of the first outer contour line in the Y-axis direction. The total length L1 is the sum of the length in the Y-axis direction of the edge on the first side of the first region portion and the length in the Y-axis direction of the edge on the first side of the third region portion. The total length L2 of the second outer contour line is the length of the second outer contour line in the Y-axis direction. The total length L2 is the sum of the length in the Y-axis direction of the edge on the second side of the second region portion and the length in the Y-axis direction of the edge on the second side of the third region portion. The second outer contour line does not include the aforementioned non-joint portion, and when the non-joint portion becomes larger in the Y-axis direction, the total length L2 of the second outer contour line becomes shorter. According to the molded body described in (1) above, the second region portion and the third region portion are integrally continuous with the first region portion, and the second region portion and the third region portion are both inclined in the same direction with respect to the first region portion. Here, a non-bonded portion that satisfies Formula 1 and Formula 2 is provided. When Formula 1 is satisfied, since the total length L2 of the second outer contour line is moderately shorter than the total length L1 of the first outer contour line, it can be said that the size of the non-bonded portion in the Y-axis direction is moderately ensured. When Formula 2 is satisfied, it can be said that the non-bonded portion described above is not excessively small or excessively large with respect to the third ridge line, and the size of the non-bonded portion in the Y-axis direction is moderately ensured. Therefore, when this molded body is obtained by press molding from a flat blank, the occurrence of wrinkles that occur when the second region portion and the third region portion are all connected along the extending direction of the third ridge line can be suppressed. In addition, during press molding, at the position of the third ridge line, a compressive force in the direction in which the second region portion and the third region portion approach each other acts, and no tension occurs at the position of the third ridge line, so no cracks occur. Therefore, no wrinkles or cracks have occurred between the second region portion and the third region portion of this molded body.

[0010] (2) In the aspect of (1) above, the molded body may be made of a steel plate having a tensile strength of 980 MPa or more. In the case of (2) above, even a molded body manufactured using a high-tensile steel plate with low formability as a blank, since a compressive force acts on the third ridge line during press molding, no cracks have occurred and its soundness is ensured.

[0011] (3) In the aspect described in (1) or (2) above, the plate thickness of the molded body may be 0.8 mm or more and 2.3 mm or less. In the case of (3) above, this molded body can be widely used as an automotive part such as a dash panel, for example.

[0012] (4) In the aspect described in any one of (1) to (3) above, the following configuration may be adopted as the molded body: A fourth region portion is further provided, which is located on the side opposite to the first region portion with the third region portion interposed therebetween and is integrally continuous with the third region portion via a fourth ridge line. The fourth region portion includes an inclined portion that inclines in the same direction as the second region portion in the arrangement direction from the first region portion toward the second region portion. In the case of (4) above, in the blank in which the first region portion and the second region portion are formed, by moving the fourth region portion relative to the first region portion in the same direction as the inclination direction of the second region portion, a portion located between the first region portion and the fourth region portion in the blank is inevitably inclined toward the one side, and thus the third region portion can be formed. Here, since the fourth region portion includes an inclined portion, for example, by forming an inclined portion in the fourth region portion when moving the fourth region portion relative to the first region portion, the material flow in the third region portion during the formation of the third region portion can be directed toward the second region portion. Therefore, since the obtained molded body is formed while the force in the compression direction acts on the third ridge line, cracking is more reliably suppressed.

[0013] (5) The blank according to one aspect of the present invention may adopt the following configuration: A flat blank to be formed into the molded body according to any one of (1) to (4) above, having a notch corresponding to the non-bonded portion. When the blank of (5) above is press-molded to manufacture the molded body of (1) above, since there is a notch at a position corresponding to the non-bonded portion, the generation of wrinkles that occur when there is no notch can be suppressed. In addition, since a force in the compression direction acts on the position that becomes the third ridge line continuous with the notch in the blank, cracking does not occur either. Therefore, when the molded body according to any one of (1) to (4) above is manufactured using this blank, wrinkles and cracks do not occur between the second region portion and the third region portion.

[0014] (6) In the aspect described in (5) above, with the separation dimension at the end of the notch being W1 (mm), the following formula 3 may be satisfied. W1 > L1 - L2 ··· (Formula 3) In the case of the above (6), since the notch satisfies Expression 3, a large interference between the portion corresponding to the second region portion and the portion corresponding to the third region portion in the blank can be surely avoided, so that wrinkles and cracks can be more surely suppressed.

[0015] (7) The method for manufacturing a molded body according to one aspect of the present invention is a method for manufacturing the molded body described in the above (4), a preparation step of preparing a blank having a first region corresponding portion corresponding to the first region portion, a second region corresponding portion corresponding to the second region portion, a third region corresponding portion corresponding to the third region portion, a fourth region corresponding portion corresponding to the fourth region portion, and a notch corresponding to the non-bonded portion; a second region portion forming step of inclining the second region corresponding portion with respect to the first region corresponding portion to the one side; a third region portion forming step of inclining the third region corresponding portion with respect to the first region corresponding portion to the one side by relatively moving the fourth region corresponding portion with respect to the first region corresponding portion toward the one side while fixing the inclination of the second region corresponding portion with respect to the first region corresponding portion; and having.

[0016] According to the method for manufacturing a molded body described in the above (7), first, a blank having a notch is prepared in the preparation step. In the subsequent second region portion forming step, a second region portion is formed on the blank. In the subsequent third region portion forming step, a third region portion is formed on the blank. At this time, since there is a notch at a position corresponding to the non-bonded portion in the blank, the generation of wrinkles that occur when there is no notch can be suppressed. In addition, since a force in the compression direction acts on the position of the blank that becomes the third ridge line continuous with the notch, cracks do not occur either. Therefore, according to this method for manufacturing a molded body, wrinkles and cracks do not occur between the second region portion and the third region portion.

[0017] (8) In the aspect described in the above (7), the preparation step may include a notch forming step of forming the notch in the blank. In the case of the above (8), by previously forming a notch in the preparation step, the transition from the second region portion forming step to the third region portion forming step can be smoothly performed without interruption.

[0018] (9) The method for manufacturing a molded body according to another aspect of the present invention is a method for manufacturing the molded body described in the above (4), a preparation step of preparing a blank including a first region corresponding portion corresponding to the first region portion, a second region corresponding portion corresponding to the second region portion, a third region corresponding portion corresponding to the third region portion, and a fourth region corresponding portion corresponding to the fourth region portion; a second region portion forming step of inclining the second region corresponding portion on one side of the front and back surfaces of the first region corresponding portion; a notch forming step of forming a notch corresponding to the non-bonded portion between the second region corresponding portion and the third region corresponding portion; a third region portion forming step of inclining the third region corresponding portion with respect to the first region corresponding portion toward the one side by relatively moving the fourth region corresponding portion toward the one side with respect to the first region corresponding portion while fixing the inclination of the second region corresponding portion with respect to the first region corresponding portion; and having.

[0019] According to the method for manufacturing a molded body described in the above (9), first, a blank is prepared in the preparation step. In the subsequent second region portion forming step, a second region portion is formed on the blank. In the subsequent notch forming step, a notch is formed in the blank. In the subsequent third region portion forming step, a third region portion is formed on the blank. At this time, since there is a notch at a position corresponding to the non-bonded portion in the blank, the generation of wrinkles that occur when there is no notch can be suppressed. In addition, since a force in the compression direction acts on a position that becomes the third ridge line continuous with the notch in the blank, cracks do not occur either. Therefore, according to this method for manufacturing a molded body, wrinkles and cracks do not occur between the second region portion and the third region portion. The notch may be formed in the preparation step as in the above (8), or may be formed in the notch forming step between the second region portion forming step and the third region portion forming step as in the above (9).

[0020] (10) In the aspect according to any one of (7) to (9) above, In the third region portion forming step, a material flow from the third region corresponding portion toward the notch may be formed by relatively moving the fourth region corresponding portion while restraining it with a material flow control means. In the case of (10) above, by restraining the fourth region corresponding portion with a material flow control means, a material flow that causes the third region corresponding portion to face the second region portion can be formed. Thereby, a force in the compression direction can be more reliably applied to a portion of the blank that becomes the third ridge line connected to the notch. Therefore, cracking can be more reliably suppressed.

[0021] (11) The mold according to one aspect of the present invention is a mold for manufacturing the molded body according to (4) above from a blank including a first region corresponding portion corresponding to the first region portion, a second region corresponding portion corresponding to the second region portion, a third region corresponding portion corresponding to the third region portion, and a fourth region corresponding portion corresponding to the fourth region portion, comprising a first mold and a second mold facing each other, wherein the first mold includes a holder having a first region holder surface on which the first region corresponding portion is disposed, a second region holder surface that is continuous with the first region holder surface and is inclined with respect to the first region holder surface to form the second region portion, and a third region holder surface that is continuous with the first region holder surface and is inclined with respect to the first region holder surface to form the third region portion, and a first pad that is disposed adjacent to the holder and has a fourth region pad surface on which the fourth region corresponding portion is placed, wherein the second mold includes a second pad having a first region pad surface facing the first region holder surface and a second region pad surface facing the second region holder surface, and a die that is disposed adjacent to the second pad and has a fourth region die surface facing the fourth region pad surface, and is provided with the above.

[0022] According to the mold described in the above (11), as an example, a molded body can be manufactured by the manufacturing method shown below. First, place the blank on the first mold (holder and the first pad). At this time, position the blank so that the first region corresponding portion is located on the first region holder surface, the second region corresponding portion is located on the second region holder surface, and the fourth region corresponding portion is located on the fourth region pad surface. Subsequently, press the second pad against the holder to sandwich the blank between the holder and the second pad. Thereby, the first region portion and the second region portion are formed on the blank. When a notch is formed in the blank in advance, without opening the mold, proceed to the molding of the third region portion and the fourth region portion. On the other hand, when no notch is formed in the blank before forming the third region portion and the fourth region portion, once open the mold, take out the blank in the middle of molding, and form a notch. Subsequently, place the blank with the notch formed again and close the mold. After that, press the second mold against the first mold. Thereby, sandwich the first region corresponding portion between the first region holder surface and the first region pad surface, sandwich the second region corresponding portion between the second region holder surface and the second region pad surface, and sandwich the fourth region corresponding portion between the fourth region pad surface and the fourth region die surface. In this state, move the combination of the first pad and the die relative to the combination of the holder and the second pad to the one side. Thereby, the third region portion and the fourth region portion are formed. At this time, since there is a notch at a position corresponding to the non-joined portion in the blank, the generation of wrinkles that occur when there is no notch can be suppressed. In addition, since a force in the compression direction acts on the position of the blank that becomes the third ridge line continuous with the notch, no cracks occur either.

[0023] (12) In the aspect described in the above (11), the second pad may include a leading pad having the first region pad surface and a trailing pad having the second region pad surface.

[0024] According to the mold described in the above (12), a molded body with cracks and wrinkles suppressed can be manufactured in the same manner as the mold described in the above (11). Furthermore, according to this mold, when pressing the second pad against the holder in the second region portion forming step, first, by pressing the preceding pad against the holder, the first region corresponding portion is sandwiched between the first region holder surface and the first region pad surface. Thereby, the blank is fixed to the holder. Subsequently, by pressing the subsequent pad against the holder, the second region corresponding portion is inclined with respect to the first region corresponding portion. Thereby, the first region portion and the second region portion are formed on the blank.

[0025] (13) In the aspect described in the above (11) or (12), the holder may include a blank holder having the first region holder surface and a punch disposed adjacent to the blank holder and having the third region holder surface.

[0026] According to the mold described in the above (13), a molded body with cracks and wrinkles suppressed can be manufactured in the same manner as the mold described in the above (11). Furthermore, according to this mold, when forming the third region portion and the fourth region portion, the combination of the first pad and the die is relatively moved to the one side with respect to the combination of the blank holder and the second pad. Also, the punch is relatively moved in a direction opposite to the one side with respect to the combination of the blank holder and the second pad. Thereby, the punch is pressed against the third region corresponding portion of the blank, and the third region portion and the fourth region portion are formed.

[0027] (14) A method for manufacturing a molded body according to still another aspect of the present invention is a method for manufacturing the molded body using the mold described in the above (11), an arranging step of arranging the blank on the first mold such that the first region corresponding portion is located on the first region holder surface, the second region corresponding portion is located on the second region holder surface, and the fourth region corresponding portion is located on the fourth region pad surface; a second region portion forming step of forming the second region portion by pressing the second pad against the holder; With the notch corresponding to the non-bonding portion formed in the blank, the second mold is pressed against the first mold, and the first region corresponding portion is sandwiched between the first region holder surface and the first region pad surface, the second region corresponding portion is sandwiched between the second region holder surface and the second region pad surface, and the fourth region corresponding portion is sandwiched between the fourth region pad surface and the fourth region die surface. Then, the first pad and the die are relatively moved toward the one side with respect to the holder and the second pad to form the third region portion, which is the third region portion forming step. has.

[0028] According to the method for manufacturing a molded body of the above (14), the same operational effects as those of the above (11) can be obtained. Therefore, a molded body with suppressed cracking and wrinkling can be manufactured.

[0029] (15) A method for manufacturing a molded body according to still another aspect of the present invention is a method for manufacturing the molded body using the mold described in the above (12), an arranging step of arranging the blank on the first mold such that the first region corresponding portion is located on the first region holder surface, the second region corresponding portion is located on the second region holder surface, and the fourth region corresponding portion is located on the fourth region pad surface; a second region portion forming step of pressing the second pad against the holder to form the second region portion; With the notch corresponding to the non-bonding portion formed in the blank, the second mold is pressed against the first mold, and the first region corresponding portion is sandwiched between the first region holder surface and the first region pad surface, the second region corresponding portion is sandwiched between the second region holder surface and the second region pad surface, and the fourth region corresponding portion is sandwiched between the fourth region pad surface and the fourth region die surface. Then, the first pad and the die are relatively moved toward the one side with respect to the holder and the second pad to form the third region portion, which is the third region portion forming step. has In the second region part forming step, after pressing the preceding pad against the holder and sandwiching the first region corresponding part between the first region holder surface and the first region pad surface, the succeeding pad is pressed against the holder to form the second region part.

[0030] According to the method for manufacturing a molded body of the above (15), the same operational effects as those of the above (12) can be obtained. Therefore, a molded body with suppressed cracks and wrinkles can be manufactured.

[0031] (16) A method for manufacturing a molded body according to still another aspect of the present invention is a method for manufacturing the molded body using the mold described in the above (13), an arranging step of arranging the blank on the first mold such that the first region corresponding part is located on the first region holder surface, the second region corresponding part is located on the second region holder surface, and the fourth region corresponding part is located on the fourth region pad surface; a second region part forming step of pressing the second pad against the holder to form the second region part; a third region part forming step of pressing the second mold against the first mold with a notch corresponding to the non-bonded part formed in the blank, sandwiching the first region corresponding part between the first region holder surface and the first region pad surface, sandwiching the second region corresponding part between the second region holder surface and the second region pad surface, sandwiching the fourth region corresponding part between the fourth region pad surface and the fourth region die surface, and relatively moving the first pad and the die toward the one side with respect to the holder and the second pad to form the third region part; which includes In the third region part forming step, with the punch positioned on the one side with respect to the blank holder, the first pad and the die are relatively moved toward the one side with respect to the blank holder and the second pad, and the punch is relatively moved in the direction opposite to the one side with respect to the blank holder and the second pad to form the third region part.

[0032] According to the method for manufacturing a molded body of (16) above, the same operational effects as those of (13) above can be obtained. Therefore, a molded body with suppressed cracks and wrinkles can be manufactured.

Effects of the Invention

[0033] According to each of the above aspects, a molded body with suppressed cracks and wrinkles can be provided. Also, according to each of the above aspects, a blank, a method for manufacturing a molded body, and a mold for obtaining the molded body can be provided.

Brief Description of the Drawings

[0034]

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Embodiments for Carrying Out the Invention

[0035] Hereinafter, embodiments of a molded body obtained by forming a metal plate, a method for manufacturing the molded body, and a mold used for this forming process will be described with reference to the drawings. In each embodiment, the case of manufacturing a dash panel, which is an example of a molded body, from a high-tensile steel sheet, which is an example of a metal plate, will be exemplified and described. However, the present invention is not limited to high-tensile steel sheets only, and may be applied to other metal plates. Further, the molded body to be manufactured by the present invention is not limited to dash panels only, and may be other structural parts. Furthermore, the molded body obtained by applying the present invention may be used as a final product as it is, or may be an intermediate product to which post-processing such as trimming is added.

[0036] <First Embodiment> [Molded Body] Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. 1 to 13. First, the molded body will be described with reference to FIG. 1. FIG. 1 is a perspective view for explaining a schematic configuration of a dash panel 100, which is a molded body to be manufactured in the present embodiment. This dash panel 100 is an automobile part. In the following description, for example, as shown in FIG. 1, each direction may be described using an X-axis direction (first direction), a Y-axis direction (second direction), and a Z-axis direction (third direction) that are orthogonal to each other. For example, the press forming direction of the dash panel 100 is the Z-axis direction (third direction). In some cases, the plane defined by the X-axis and the Z-axis may be described as the first plane, the plane defined by the X-axis and the Y-axis may be described as the second plane, and the plane defined by the Y-axis and the Z-axis may be described as the third plane.

[0037] The dash panel 100 is obtained by punching a high-tensile steel sheet (metal sheet) with a plate thickness t of 1.2 mm and a tensile strength of 980 MPa to obtain a notched blank B100 (described later), and then cold-press forming (pad drawing) the notched blank B100. The plate thickness t can be appropriately selected from the range of 0.8 mm to 2.3 mm. The plate thickness t here refers to the thickness at the time of the notched blank B100, but since it basically does not change significantly after being processed into the dash panel 100, the thickness of the dash panel 100 is also within the range of 0.8 mm to 2.3 mm. As the plate thickness t, for example, at the central position in the Y-axis direction in the main wall portion 10 described later, the average value of the plate thickness measured at three points at both ends and the center in the X-axis direction can be adopted. Also, the tensile strength of the notched blank B100 shown in Fig. 3A may exceed 980 MPa, or conversely, may be less than 980 MPa. When the tensile strength of the notched blank B100 increases, the formability decreases. Therefore, when the present invention is applied to a high-tensile steel sheet with a tensile strength of 980 MPa or more, the effect of suppressing wrinkles and cracks can be most effectively exerted. As the tensile strength, for example, a test piece can be cut out from the central positions in both the X-axis direction and the Y-axis direction in the main wall portion 10 described later, and the tensile strength measured with that test piece can be adopted. Here, generally, the tensile strength of a steel sheet has anisotropy. Therefore, when cutting out the above-mentioned test pieces, a plurality of test pieces can be cut out, and after measuring the tensile strength in different directions for each test piece, the highest value among the measurement results can also be adopted as the tensile strength of the notched blank B100.

[0038] As shown in FIG. 1, the dash panel 100 includes a main wall portion (first region portion) 10, an inclined wall portion (second region portion) 20 connected to the main wall portion 10 via a first connection portion (first ridge line) 11, a pair of first side wall portions (third region portions) 30 disposed on both sides of the main wall portion 10 in the Y-axis direction and connected to the main wall portion 10 via a second connection portion (second ridge line) 12, and a second side wall portion (fourth region portion) 40 connected to the opposite side of the main wall portion 10 with the first side wall portion 30 interposed therebetween via a fourth connection portion 14. The dash panel 100 is symmetric about the Y-axis direction. Although the inclined wall portion 20 and the first side wall portion 30 are connected via a third connection portion (third ridge line) 13, a notch 50 is formed in the extending direction of the third connection portion 13. Therefore, the inclined wall portion 20 and the first side wall portion 30 are partially connected.

[0039] The first connection portion 11 is a fold line connecting the main wall portion 10 and the inclined wall portion 20, and is formed substantially linearly along the Y-axis direction. When the first connection portion 11 is viewed in a longitudinal section perpendicular to the Y-axis direction, it has an inverted V-shape with an obtuse angle having a curved top. The second connection portion 12 is a fold line connecting the main wall portion 10 and each first side wall portion 30, and is formed in a curved shape in plan view. When the second connection portion 12 is viewed in a longitudinal section perpendicular to the X-axis direction, it has an inverted V-shape with an obtuse angle having a curved top. The second connection portion 12 extends in a direction inclined in both the X-axis direction and the Y-axis direction in plan view. The fourth connection portion 14 is a fold line connecting the first side wall portion 30 and the second side wall portion 40, and is formed linearly in plan view. When the fourth connection portion 14 is viewed in a longitudinal section perpendicular to the X-axis direction, it has a V-shape with an obtuse angle having a curved bottom. The third connection portion 13 is a fold line connecting the inclined wall portion 20 and the first side wall portion 30, and is formed linearly in plan view. When the third connection portion 13 is viewed in a longitudinal section perpendicular to the X-axis direction, it has an inverted V-shape with an obtuse angle having a curved top.

[0040] The main wall portion 10 is formed in a planar shape that extends along a plane direction orthogonal to the Z-axis direction, that is, along a second plane defined by the X-axis and the Y-axis. When viewed in plan, the main wall portion 10 is formed in a substantially trapezoidal shape in which the width dimension (dimension in the Y-axis direction) gradually decreases as it approaches the first connecting portion 11 along the X-axis direction.

[0041] The inclined wall portion 20 has an edge in the X-axis direction integrally connected to the main wall portion 10 via the first connecting portion 11. The inclined wall portion 20 is inclined with respect to the main wall portion 10 in the Z-axis direction. In FIG. 1, when the visible surface in FIG. 1 is defined as the front surface and the surface facing the opposite side is defined as the back surface among the front and back surfaces of the main wall portion 10, the inclined wall portion 20 is inclined toward the one side facing the back surface. The inclined wall portion 20 is formed in a substantially trapezoidal planar shape in which the width dimension gradually increases as it moves away from the first connecting portion 11 when viewed in plan.

[0042] The first side wall portion 30 has an edge in the Y-axis direction integrally connected to the main wall portion 10 via the second connecting portion 12. The first side wall portion 30 is inclined toward the one side with respect to the main wall portion 10. That is, the first side wall portion 30 is inclined toward the one side that is the same direction as the inclined wall portion 20. Therefore, since the inclined wall portion 20 and the pair of first side wall portions 30 are inclined in the same direction, an inner space 100P, which is a recess partitioned by these three wall portions, is formed.

[0043] A concave curved surface wall portion 30A and a convex curved surface wall portion 30B are formed inside the first side wall portion 30. A ridge line 15 is formed between the concave curved surface wall portion 30A and the convex curved surface wall portion 30B. The concave curved surface wall portion 30A is a wall portion that bulges toward the inner space 100P. In FIG. 1, the front side of the paper surface is a concave curved surface, and the back side thereof is a convex curved surface. The concave curved surface wall portion 30A is a wall portion partitioned by the second connection portion 12, the ridge line 15, the fourth connection portion 14, the third connection portion 13, and the notch 50. When the notched blank B100 (described later), which is the material of the dash panel 100, is press-molded, a part of the concave curved surface wall portion 30A is thickened, so that a thick portion thicker than the notched blank B100 is formed. Therefore, the concave curved surface wall portion 30A is thicker than the main wall portion 10 that has not been plastically processed. The recess formed in the concave curved surface wall portion 30A becomes a wheel house in which a part of the tire is accommodated when the dash panel 100 is assembled to an automobile. That is, in this dash panel 100, a pair of wheel houses are integrally formed on both sides of the main wall portion 10.

[0044] The convex curved surface wall portion 30B is a wall portion that bulges toward the side opposite to the concave curved surface wall portion 30A. In FIG. 1, the front side of the paper surface is a gently convex curved surface, and the back side thereof is a gently concave curved surface. The convex curved surface wall portion 30B is a wall portion partitioned by the ridge line 15 and the fourth connection portion 14. The convex curved surface wall portion 30B is integrally formed with the concave curved surface wall portion 30A via the ridge line 15. Further, the convex curved surface wall portion 30B is integrally formed with the second side wall portion 40 via the fourth connection portion 14.

[0045] The second side wall portion 40 has a side flat portion 40A and a side inclined portion 40B. The side flat portion 40A is flat and rectangular and is substantially parallel to the main wall portion 10. The side inclined portion 40B is integrally continuous with the side flat portion 40A via the ridge line 16. The side inclined portion 40B is flat and rectangular and is inclined toward the one side in the same manner as the inclined wall portion 20. The ridge line 16 is a fold connecting between the side flat portion 40A and the side inclined portion 40B and is formed in a substantially straight line along the Y-axis direction. When the ridge line 16 is viewed in a longitudinal section perpendicular to the Y-axis direction, it has an inverted V shape with a curved top portion at an obtuse angle.

[0046] The notch 50 is a triangular space formed between the inclined wall portion 20 and the first side wall portion 30. More specifically, it is a triangular space having the edge 50b of the concave curved wall portion 30A and the edge 50a of the inclined wall portion 20 as two sides and an open bottom. Both the edges 50a and 50b are linear. Also, the edge 50a is shorter than the edge 50b. The edges 50a and 50b are connected at their tops, and the top is in an arc shape with a small radius of curvature. The top is continuous with the third connecting portion 13. And the notch 50 is formed along the extending direction of the third connecting portion 13. The edge 50a is inclined so as to approach the center in the width direction (center in the Y-axis direction) of the dash panel 100 as it approaches the top. Similarly, the edge 50b is also inclined so as to approach the center in the width direction of the dash panel 100 as it approaches the top. Thus, although the edges 50a and 50b are inclined in the same direction, the width dimension between these edges 50a and 50b forms an inverted V shape that gradually widens as it moves away from the top closest to the third connecting portion 13.

[0047] As described above, the molded body obtained by applying the present invention may be used as the final product as it is, or may be an intermediate product to which post-processing such as trimming is applied. The dash panel 100 of the present embodiment is an intermediate product at the time of FIG. 1, and further, the hatched portion is removed by trimming to become the final product.

[0048] As described above, the dash panel 100 of the present embodiment includes a main wall portion (first region portion) 10 having a first connecting portion (first ridge line) 11 and a second connecting portion (second ridge line) 12 arranged with the corner C shown in FIG. 1 interposed therebetween; an inclined wall portion (second region portion) 20 integrally connected to the main wall portion 10 via the first connecting portion 11 and inclined on the one side of the front and back surfaces of the main wall portion 10; and a first side wall portion (third region portion) 30 integrally connected to the main wall portion 10 via the second connecting portion 12, partially and integrally connected to the inclined wall portion 20 via a third connecting portion (third ridge line) 13 connected to the corner C, and inclined on the one side with respect to the main wall portion 10. The first connecting portion 11, the second connecting portion 12, and the third connecting portion 13 are connected to each other at the corner C.

[0049] When the total length of the outer contour line OL1 (hereinafter referred to as the first outer contour line) formed by the main wall portion 10 and the first side wall portion 30 is L1 (mm), and the total length of the outer contour line OL2 (hereinafter referred to as the second outer contour line) formed by the inclined wall portion 20 and the first side wall portion 30 is L2 (mm), the following formula (4) is satisfied. L1 > 1.1 × L2 ··· (Formula 4)

[0050] Here, the first outer contour line OL1 is an outer contour line formed by the edge located on the first side in the X-axis direction among the two end edges in the X-axis direction of the main wall portion 10 and the first side wall portion 30. The second outer contour line OL2 is an outer contour line formed by the edge located on the second side in the X-axis direction among the two end edges in the X-axis direction of the inclined wall portion 20 and the first side wall portion 30. Here, the first side in the X-axis direction is the side where the main wall portion 10 is located with respect to the inclined wall portion 20, and the second side in the X-axis direction is the side where the inclined wall portion 20 is located with respect to the main wall portion 10. The first connecting portion 11 is located on the second side with respect to the main wall portion 10 and on the first side with respect to the inclined wall portion 20. Both the first outer contour line OL1 and the second outer contour line OL2 extend in the Y-axis direction. The total length L1 of the first outer contour line OL1 is the length of the first outer contour line OL1 in the Y-axis direction, which is the sum of the length L11 in the Y-axis direction of the edge on the first side of the main wall portion 10 and the length L12 in the Y-axis direction of the edge on the first side of the first side wall portion 30. However, in the illustrated example, since two first side wall portions 30 are arranged in the Y-axis direction, the total length L1 of the first outer contour line OL1 includes the lengths L12 of each of the two first side wall portions 30. The total length L2 of the second outer contour line OL2 is the length of the second outer contour line OL2 in the Y-axis direction, and is the sum of the length L21 in the Y-axis direction of the edge on the second side of the inclined wall portion 20 and the length L22 in the Y-axis direction of the edge on the second side of the first side wall portion 30. However, in the illustrated example, since two first side wall portions 30 are arranged in the Y-axis direction, the total length L2 of the second outer contour line OL2 includes the length L22 of each of the two first side wall portions 30. Further, the second outer contour line OL2 does not include the aforementioned notch 50, and when the notch 50 becomes larger in the Y-axis direction, the total length L2 of the second outer contour line OL2 becomes shorter.

[0051] Note that in the dash panel 100, the length of the second side wall portion 40 is not included in the above total lengths L1 and L2. However, when the length dimension along the total length L1 and the length dimension along the total length L2 in the second side wall portion 40 are the same, the dimension of the second side wall portion 40 may be included in the total lengths L1 and L2 in the above formula 4.

[0052] In addition, let the total length of the adjacent portions along the extension direction of the third connecting portion 13 between the inclined wall portion 20 and the first side wall portion 30 be L3 (mm), and let the length of the notch (non-joint portion) 50 obtained by removing the length of the third connecting portion 13 from this total length L3 be L4 (mm). Then, the following (Formula 5) is satisfied. When the lengths are different from each other like the above edges 50a and 50b, their average value is obtained and taken as L4. And L3 is obtained by adding the length of the third connecting portion 13 to the obtained L4. 0.8×L3 < L4 < 0.9×L3 ··· (Formula 5)

[0053] Furthermore, in this notched blank B100 (described later), for each notch B50 that becomes a non-joint portion, when the separation dimension at its end is W1 (mm), the following formula 6 is satisfied with respect to the above total lengths L1 (mm) and L2 (mm). Here, the separation dimension W1 is the separation dimension between the above edges 50a and 50b. W1 > L1 - L2 ··· (Formula 6)

[0054] According to the dashboard 100 having the above configuration, the inclined wall portion 20 and the first side wall portion 30 are integrally connected to the main wall portion 10, and the inclined wall portion 20 and the first side wall portion 30 are both inclined in the same direction (the one side) with respect to the main wall portion 10. Here, the notch 50 that satisfies Formula 4 and Formula 5 is provided. When Formula 1 is satisfied, since the total length L2 of the second outer contour line OL2 is moderately shorter than the total length L1 of the first outer contour line OL1, it can be said that the size of the notch 50 in the Y-axis direction is moderately ensured. When Formula 2 is satisfied, it can be said that the above-mentioned notch 50 is not excessively small or excessively large with respect to the third connecting portion 13, and the size of the notch 50 in the Y-axis direction is moderately ensured. Therefore, when this dashboard 100 is obtained by press forming from a flat notched blank B100, the occurrence of wrinkles that occur when the inclined wall portion 20 and the first side wall portion 30 are all connected along the extending direction of the third connecting portion 13 can be suppressed. In addition, during press forming, a compressive force in the direction in which the inclined wall portion 20 and the first side wall portion 30 approach each other acts on the position of the third connecting portion 13, and no tension occurs at the position of the third connecting portion 13, so no cracks occur. Therefore, no wrinkles or cracks have occurred between the inclined wall portion 20 and the first side wall portion 30 of this dashboard 100.

[0055] Further, the dashboard 100 is made of a steel plate having a tensile strength of 980 MPa or more. Thus, even if the dashboard 100 is a formed body manufactured using a high-tensile steel plate with low formability as the notched blank B100, since a compressive force acts on the third connecting portion 13 during press forming, no cracks have occurred and its soundness is ensured.

[0056] Also, the plate thickness of the dashboard 100 is 1.2 mm, which is within the thickness range of 0.8 mm or more and 2.3 mm or less. By setting the thickness of the formed body within this range, the present invention can be widely applied, for example, as an automotive part such as the dashboard 100 of the present embodiment.

[0057] Further, the dash panel 100 is located on the side opposite to the main wall portion 10 with the first side wall portion 30 interposed therebetween, and further includes a second side wall portion (fourth region portion) 40 integrally connected to the first side wall portion 30 via a fourth connecting portion (fourth ridge line) 14. And the second side wall portion 40 includes a side inclined portion 40B that is an inclined portion inclined in the same direction as the inclined wall portion 20 in the arrangement direction from the main wall portion 10 toward the inclined wall portion 20. According to this configuration, in the notched blank B100 in which the inclined wall portion 20 and the first side wall portion 30 are formed, by moving the second side wall portion 40 relative to the main wall portion 10 in the same direction as the inclination direction of the inclined wall portion 20, the first side wall portion 30 can be formed. Here, since the second side wall portion 40 includes the side inclined portion 40B, for example, when moving the second side wall portion 40 relative to the main wall portion 10, by forming the side inclined portion 40B in the second side wall portion 40 at the same time, the material flow in the first side wall portion 30 when forming the first side wall portion 30 can be directed toward the inclined wall portion 20. Therefore, since the obtained dash panel 100 is formed while a compressive force acts on the third connecting portion 13, cracking is more reliably suppressed.

[0058] [Forming Body Manufacturing Method and Mold] Hereinafter, with reference to FIGS. 2 to 4, a forming body manufacturing method for manufacturing the dash panel 100 will be described. FIG. 2 is a flowchart for explaining the forming body manufacturing method of the present embodiment. FIG. 3A is a perspective view of the notched blank B100 used in the forming body manufacturing method. FIG. 3B is a perspective view of an intermediate molded product obtained by the forming body manufacturing method. FIG. 3C is a perspective view of the dash panel 100 which is the formed body obtained by the forming body manufacturing method. FIG. 4 is a plan view for explaining the first region corresponding portion to the fourth region corresponding portion in the notched blank B100 shown in FIG. 3A.

[0059] As shown in FIG. 2, the method for manufacturing a molded body according to the present embodiment includes a notched blank preparation step (preparation step) S1, a notched blank setting step (arrangement step) S2, an intermediate molded body forming step (second region portion forming step) S3, a final molded body forming step (third region portion forming step) S4, and a molded body taking-out step S5. The molded body obtained after the molded body taking-out step S5 is the dash panel 100 shown in FIG. 1. The details of each step will be described below.

[0060] (1) Notched blank preparation step S1 In the notched blank preparation step, a high-tensile steel sheet (metal sheet) with a plate thickness t of 1.2 mm and a tensile strength of 980 MPa is processed to prepare a notched blank B100. Here, 1.2 mm is exemplified as the plate thickness t, but it may be selected from within the thickness range of 0.8 mm or more and 2.3 mm or less as necessary. Also, regarding the tensile strength, a steel sheet exceeding 980 MPa or less than 980 MPa may be selected as necessary. The method for forming the notched blank B100 is preferably punching, but other processing means such as machining, plasma cutting, and laser cutting may be adopted instead of punching.

[0061] As shown in FIGS. 3A and 4, the notched blank B100 has an outer shape in which two notches B50 are formed in a rectangular high-tensile steel sheet (metal sheet). As shown in FIG. 4, the notched blank B100 includes a main wall corresponding portion B10, a pair of inclined wall corresponding portions B20, a pair of first side wall corresponding portions B30, a pair of second side wall corresponding portions B40, a pair of notches B50, a pair of first connection portion corresponding portions B11, a pair of second connection portion corresponding portions B12, a pair of third connection portion corresponding portions B13, and a pair of fourth connection portion corresponding portions B14. The main wall corresponding portion B10 is the portion that becomes the main wall portion 10 after press forming. The inclined wall corresponding portion B20 is the portion that becomes the inclined wall portion 20 after press forming. The first side wall corresponding portion B30 is the portion that becomes the first side wall portion 30 after press forming. The second side wall corresponding portion B40 is the portion that becomes the second side wall portion 40 after press forming. The notch B50 is the portion that becomes the notch 50 after press forming. The first connection portion corresponding portion B11 is the portion that becomes the first connection portion 11 after press forming. The second connection portion corresponding portion B12 is the portion that becomes the second connection portion 12 after press forming. The third connection portion corresponding portion B13 is the portion that becomes the third connection portion 13 after press forming. The fourth connection portion corresponding portion B14 is the portion that becomes the fourth connection portion 14 after press forming. Note that a part of the second side wall corresponding portion B40 moves during press forming and becomes a part of the first side wall portion 30.

[0062] The pair of notches B50 are arranged at symmetric positions with respect to the center in the width direction (Y-axis direction) of the notched blank B100. Each notch B50 is located between the inclined wall corresponding portion B20 and the first side wall corresponding portion B30, respectively. The pair of notches B50 have a symmetric shape with respect to the center in the width direction. The outer contour line (the first side outer contour line in the X-axis direction) along the Y-axis direction on the side where each notch B50 is not formed in the blank B100 is denoted by the symbol E1, and the outer contour line (the second side outer contour line in the X-axis direction) along the Y-axis direction on the side where each notch B50 is formed in the blank B100 is denoted by the symbol E2. In this case, each notch B50 is open in the outer contour line E2.

[0063] Each notch B50 is a triangular space formed between the inclined wall corresponding part B20 and the first side wall corresponding part B30. More specifically, it is a triangular space having the edge B50b of the first side wall corresponding part B30 and the edge B50a of the inclined wall corresponding part B20 as two sides and an open bottom. The edges B50a and B50b are both linear. Also, the edge B50a is shorter than the edge B50b. The edges B50a and B50b are connected at their tops, and the top is in an arc shape with a small radius of curvature. The top is continuous with the third connection part corresponding part B13. And the notch B50 is formed along the extension direction of the third connection part corresponding part B13. The edge B50a is inclined so as to approach the center in the width direction of the notched blank B100 as it approaches the top. Similarly, the edge B50b is also inclined so as to approach the center in the width direction of the notched blank B100 as it approaches the top. Thus, the edges B50a and B50b are inclined in the same direction, but the width dimension gradually widens in an inverted V shape as they move away from the top closest to the third connection part corresponding part B13 between these edges B50a and B50b.

[0064] The configuration (position, shape, size) of the notch B50 is first assumed to be the case of forming the dash panel 100 from a rectangular blank without the notch B50, and the position, shape, and size of wrinkles expected to be generated by the material flow when forming the first side wall portion 30 are obtained and set based on this result. Here, the position, shape, and size of the wrinkles may be obtained by numerical calculation using CAE (computer aided engineering), or may be obtained based on the results of actual prototyping. And the part where the wrinkles occur is set as the notch B50. Thereby, the compressive force when press-forming the first side wall corresponding part B30 can be absorbed as the force closing the notch B50, so that it is possible to suppress the concentration of material between the inclined wall corresponding part B20 and the first side wall corresponding part B30 to form wrinkles.

[0065] The notch B50 is not limited to an inverted V shape and can be set according to the material flow (material displacement) when forming the first side wall portion 30. Further, it is preferable that the notch B50 is included in the region to be removed before becoming the final product. For example, in the present embodiment, the portion hatched in FIG. 4 is removed by post-processing using a trimming press device (not shown).

[0066] (2) Notched blank setting step S2 In this step, the notched blank B100 obtained in the notched blank step is set in the mold D100 described later. That is, as shown in FIG. 6, the notched blank B100 is placed and positioned in the mold D100.

[0067] (3) Intermediate molded body forming step S3 In this step, the notched blank B100 is press-formed by the mold to form an intermediate molded product W100. Before the description of this step, the mold (hereinafter, mold D100) will be described with reference to the perspective view of FIG. 5.

[0068] The mold D100 is mounted on a press molding device (not shown) to constitute a molded body manufacturing device. The mold D100 includes an upper mold U100 (second mold) and a lower mold L100 (first mold) that can move relative to the upper mold U100 along the direction of arrow UD. The lower mold L100 includes a holder L101 that can move in the vertical direction (Z-axis direction) indicated by reference sign P1, and lower pads L102, L103 (first pads) that are arranged on both sides of the holder L101 in the Y-axis direction and can move in the vertical direction (Z-axis direction) indicated by reference sign P2.

[0069] The holder L101 includes a holder top surface L101a (first region holder surface), a holder first inclined surface L101b (second region holder surface), and a holder second inclined surface L101c (third region holder surface). On the holder top surface L101a, the main wall corresponding portion B10 of the notched blank B100 is disposed. Both the holder first inclined surface L101b and the holder second inclined surface L101c are continuous with the holder top surface L101a and are inclined with respect to the holder top surface L101a. The holder first inclined surface L101b forms the inclined wall portion 20. The holder second inclined surface L101c forms the first side wall portion 30. The lower pads 102, 103 include pad top surfaces L102a, L103a (fourth region pad surfaces). On the pad top surfaces L102a, L103a, the second side wall corresponding portion B40 of the notched blank B100 is placed.

[0070] The upper die U100 includes an upper pad U101 (second pad), a pad buffer mechanism (not shown) for suspending and supporting the upper pad U101, dies U102, U103 arranged at intervals on both sides of the upper pad U101 in the Y-axis direction, and a die buffer mechanism (not shown) for suspending and supporting the dies U102, U103.

[0071] The upper pad U101 includes a pad bottom surface U101a (first region pad surface) and a pad inclined surface U101b (second region pad surface). The pad bottom surface U101a faces the holder top surface L101a. The pad inclined surface U101b faces the holder first inclined surface L101b. The dies U102, U103 include die first bottom surfaces U102a, U103a (fourth region die surfaces) and die second bottom surfaces U102b, U103b (third region die surfaces). The die first bottom surfaces U102a, U103a face the pad top surfaces L102a, L103a. The die second bottom surfaces U102b, U103b face the holder second inclined surface L101c. The pad buffer mechanism and the die buffer mechanism are mechanisms for receiving the force during press forming, and a press cushion, a gas cylinder, a spring, etc. can be adopted.

[0072] Each of the above components of the mold D100 includes a main wall forming portion D10, an inclined wall forming portion D20, a first side wall forming portion D30, a second side wall forming portion D40, a first connection portion forming portion D11, and a second connection portion forming portion D12. The main wall forming portion D10 is the portion that forms the main wall portion 10 of the dashboard 100 shown in FIG. 1. The inclined wall forming portion D20 is the portion that forms the inclined wall portion 20 of the dashboard 100. The first side wall forming portion D30 is the portion that forms the first side wall portion 30 of the dashboard 100. The second side wall forming portion D40 is the portion that forms the second side wall portion 40 of the dashboard 100. The first connection portion forming portion D11 is the portion that forms the first connection portion 11 of the dashboard 100. The second connection portion forming portion D12 is the portion that forms the second connection portion 12 of the dashboard 100.

[0073] The main wall forming portion D10, the inclined wall forming portion D20, the first side wall forming portion D30, the second side wall forming portion D40, the first connection portion forming portion D11, and the second connection portion forming portion D12 are constituted by the respective forming surfaces formed on the lower mold L100 and the respective forming surfaces formed on the upper mold U100 facing each other. That is, as shown in FIG. 5, the main wall forming portion D10, the inclined wall forming portion D20, and the first connection portion forming portion D11 are constituted by the forming surface of the holder L101 and the forming surface of the upper pad U101. For example, the main wall forming portion D10 is constituted by the top surface L101a of the holder and the bottom surface U101a of the pad. The inclined wall forming portion D20 is constituted by the first inclined surface L101b of the holder and the inclined surface U101b of the pad. Also, the second connection portion forming portion D12 is constituted by the edges formed on both sides of the holder L101 in the Y-axis direction.

[0074] In addition, the first side wall forming portion D30 is constituted by the forming surface of the holder L101 and the respective forming surfaces of the dies U102, U103. The first side wall forming portion D30 is constituted by the second inclined surface L101c of the holder and the second bottom surfaces U102b, U103b (third region die surfaces) of the dies. Note that the first side wall forming portion D30 includes a concave curved surface wall portion D30A for forming the concave curved surface wall portion 30A and a convex curved surface wall portion D30B for forming the convex curved surface wall portion 30B. Both the concave curved surface wall portion D30A and the convex curved surface wall portion D30B are formed on both sides in the Y-axis direction of the holder L101 and on the dies U102 and U103.

[0075] The second side wall forming portion D40 is composed of the forming surfaces of the lower pads L102 and L103 and the forming surfaces of the dies U102 and U103. The second side wall forming portion D40 is composed of the top surfaces L102a and L103a of the pads and the first bottom surfaces U102a and U103a of the dies.

[0076] The above-mentioned mold D100 further includes a draw bead D50 (material flow control means). The draw bead D50 partially and strongly clamps the portion W40 corresponding to the second side wall of the intermediate molded product W100. By this clamping, when forming the first side wall portion 30 from the portion W30 corresponding to the first side wall, the material flow from the portion W30 corresponding to the first side wall toward the portion W20 corresponding to the inclined wall is controlled. The draw bead D50 is a convex body that is long along the X-axis direction, and a pair of draw beads D50 are arranged side by side along the X-axis direction on the lower pad L102. Similarly, a pair of draw beads D50 are also arranged side by side along the X-axis direction on the lower pad L103. The pair of draw beads D50 may be provided on only one of the lower pad L102 and the die U102, or may be provided on both. Similarly, the pair of draw beads D50 may be provided on only one of the lower pad L103 and the die U103, or may be provided on both. The draw bead D50 is provided on the second side wall forming portion D40 (the top surfaces L102a and L103a of the pads, the first bottom surfaces U102a and U103a of the dies).

[0077] Using the mold D100 having the configuration described above, this process (intermediate molded body forming process S3) of forming the intermediate molded product W100 shown in FIG. 3B from the blank B100 shown in FIG. 3A will be described with reference to FIGS. 6 and 7. First, as described with reference to FIG. 6 in the previous process, a notched blank B100 is set on the lower die L100. When setting the notched blank B100 on the lower die L100, it is preferable to position it, for example, with reference to the first connection part forming part D11 or the second connection part forming part D12.

[0078] Next, as shown in FIG. 7, the lower die L100 is raised in the UD direction. As a result, the notched blank B100 is sandwiched between the upper die U100 and the lower die L100 and press-formed. That is, with the upper pad U101 and the dies U102, U103 arranged at the same height position, the holder L101 on which the notched blank B100 is placed and the lower pads L102, L103 are simultaneously moved upward. Then, by completely closing the space between the upper die U100 and the lower die L100, an intermediate molded product W100 is formed. As shown in FIG. 3B, the intermediate molded product W100 includes a main wall corresponding part W10, an inclined wall corresponding part W20 connected to the main wall corresponding part W10 via a first connection part corresponding part W11, and a first side wall corresponding part W30 connected to the main wall corresponding part W10 via a second connection part corresponding part W12. Thus, the intermediate molded body forming process S3 is completed, but the mold D100 remains closed and moves to the next process.

[0079] (4) Final molded body forming process S4 In this process, the intermediate molded product W100 obtained in the previous process is further press-formed (pad drawing forming) while being set in the mold D100 to obtain a dash panel 100. Hereinafter, the details of this process will be described with reference to the drawings including FIG. 8. FIG. 8 is a perspective view showing a state in which the dash panel 100 is formed by performing pad drawing forming in which the combination of the lower pad L102 and the die U102 and the combination of the lower pad L103 and the die U103 are relatively lowered with respect to the combination of the holder L101 and the upper pad U101 after the state shown in FIG. 7.

[0080] This process starts from the state where the above intermediate molded body forming process S3 has been completed. As shown in Fig. 7, the intermediate molded product W100 in the state where the intermediate molded body forming process S3 has been completed has a main wall corresponding part W10 and an inclined wall corresponding part W20 held between a holder L101 and an upper pad U101. Also, the left and right first side wall corresponding parts W30 are sandwiched between a die U102 and a lower pad L102 and between a die U103 and a lower pad L103, respectively.

[0081] Next, the dies U102 and lower pads L102 and the dies U103 and lower pads L103 are lowered in the direction of arrow TP1 in Fig. 8 with respect to the holder L101 and the upper pad U101. As a result, the first side wall part 30 is formed and the dashboard 100 is manufactured. When forming the first side wall part 30, the second side wall corresponding part W40 is strongly sandwiched by a draw bead D50. Thereby, a difference in the degree of sandwiching occurs between the portion sandwiched by the draw bead D50 and its peripheral portion within the second side wall corresponding part W40. Thereby, when forming the first side wall part 30 from the first side wall corresponding part W30, a material flow can be formed in the direction from the first side wall corresponding part W30 toward the inclined wall corresponding part W20.

[0082] Hereinafter, the process of forming the concave curved surface wall part 30A in this process will be described with reference to Figs. 9 to 10D. Fig. 9 is a partially enlarged perspective view for explaining in detail the process of forming the first side wall part 30 in the molded body manufacturing method using the mold D100. Fig. 10A is a partially enlarged view for explaining the initial stage of forming the first side wall part 30, where (a) is a longitudinal sectional view and (b) is a perspective view. Fig. 10B is a partially enlarged view for explaining the continuation of Fig. 10A, where (a) is a longitudinal sectional view and (b) is a perspective view. Fig. 10C is a partially enlarged view for explaining the continuation of Fig. 10B, where (a) is a longitudinal sectional view and (b) is a perspective view. Fig. 10D is a partially enlarged view for explaining the continuation of Fig. 10C, where (a) is a longitudinal sectional view and (b) is a perspective view.

[0083] As described above, when forming the first side wall corresponding portion W30 into the first side wall portion 30, the second side wall corresponding portion W40 is partially and strongly clamped by the draw bead D50. If press forming is continued while maintaining this clamping, as shown in FIG. 9, the shape of the first side wall corresponding portion W30 gradually changes. Here, the reference numerals WL1, WL2, WL3, and WL4 shown in FIG. 9 respectively show how the outer shape changes in order from the time point of the intermediate molded product W100 (reference numeral WL1) to the reference numeral WL2 (first stage), the reference numeral WL3 (second stage), and the time point of the dash panel 100 (reference numeral WL4). Similarly, the reference numerals ML2 and ML3 shown in FIG. 9 show the process in which the concave curved surface wall portion 30A is gradually formed, the reference numeral ML2 corresponding to the first stage, and the reference numeral ML3 corresponding to the second stage.

[0084] First, as shown in FIG. 10A(a), before the formation of the concave curved surface wall portion 30A starts, the cross section showing the first side wall corresponding portion W30 of the intermediate molded product W100 has a cross-sectional shape in which the main wall corresponding portion W10 and the inclined wall corresponding portion W20 are continuous at the first connection portion corresponding portion W11 when viewed along the Y-axis direction.

[0085] Next, as shown in FIG. 10B(a), in the first stage where the concave curved surface wall portion 30A starts to be formed, a forming line ML2 in the process of forming the concave curved surface wall portion 30A is formed. Here, a dimensional difference (G11 + G12 > G13) between the total dimension of each of the two straight line dimensions G11 and G12 forming the bent portion (the bent portion in the state before the concave curved surface wall portion 30A is formed) formed in the first side wall corresponding portion W30 of the intermediate molded product W100 and the dimension G13 of the forming line ML2 causes excess material. Such excess material causes wrinkles, but in this embodiment, since the notch W50 is formed in advance, the generation of wrinkles is suppressed. That is, as shown by the arrow T50 in FIG. 10B(b), the edge B50a of the first side wall corresponding portion W30 moves toward the edge B50b, and the interval of the notch W50 is reduced. As a result, out-of-plane deformation such as wrinkles caused by the excess material formed in the first side wall corresponding portion W30 is suppressed from occurring, and excessive compressive stress is suppressed from being generated.

[0086] Next, as shown in FIG. 10C(a), in the second stage where the formation of the concave curved surface wall portion 30A has progressed, a forming line ML3 is formed while the concave curved surface wall portion 30A is being formed. Here, a larger excess thickness is generated by the difference in dimensions between the total dimension of each of the two straight line dimensions G11 and G12 forming the bent portion formed in the first side wall corresponding portion W30 of the intermediate molded product W100 and the dimension G14 of the forming line ML3 (G11 + G12 > G14). However, as shown by the arrow T50 in FIG. 10C(b), the edge B50a of the first side wall corresponding portion W30 further moves toward the edge B50b, and the interval of the notch W50 further decreases. As a result, wrinkles and excessive compressive stress continue to be suppressed at this time.

[0087] Next, as shown in FIG. 10D(a), when the press forming is further advanced, a ridge line 15 and a third connecting portion 13 having the concave curved surface wall portion 30A are formed. Even at this time, as shown by the arrow T50 in FIG. 10D(b), the edge B50a of the first side wall corresponding portion W30 further moves toward the edge B50b, but the generation of excess thickness continues to be suppressed by the further reduction of the interval of the notch W50. Moreover, since only a force in the compression direction acts on the third connecting portion 13, no cracks occur. Therefore, it becomes possible to manufacture the dashboard 100 in which the occurrence of cracks and wrinkles is suppressed while having a complicated shape.

[0088] As described above, the method for manufacturing a molded body according to the present embodiment includes, as summarized below, a notched blank preparation step (preparation step) S1, an intermediate molded body forming step (second region portion forming step) S3, and a final molded body forming step (third region portion forming step) S4. In the notched blank preparation step S1, a notched blank B100 is prepared. This notched blank preparation step S1 includes a notch forming step of forming a notch B50 in a rectangular blank. The notched blank B100 thus prepared has a main wall corresponding portion (first region corresponding portion) B10 corresponding to the main wall portion (first region portion) 10, an inclined wall corresponding portion (second region corresponding portion) B20 corresponding to the inclined wall portion (second region portion) 20, a first side wall corresponding portion (third region corresponding portion) B30 corresponding to the first side wall portion (third region portion) 30, a second side wall corresponding portion (fourth region corresponding portion) B40 corresponding to the second side wall portion (fourth region portion) 40, and a notch B50 corresponding to the non-bonded portion. In the intermediate formed body forming step (second region portion forming step) S3, the inclined wall corresponding portion W20 is inclined to the one side with respect to the main wall corresponding portion W10. In the final formed body forming step (third region portion forming step) S4, while fixing the inclination of the inclined wall corresponding portion W20 with respect to the main wall corresponding portion W10, the first side wall corresponding portion W30 is relatively moved toward the one side with respect to the main wall corresponding portion W10. At this time, by relatively moving the second side wall corresponding portion W40 while restraining it with a draw bead (material flow control means) D50, a material flow from the first side wall corresponding portion W30 toward the notch W50 is formed.

[0089] According to the above formed body manufacturing method, first, in the notched blank preparation step S1, a notched blank B100 having a notch B50 is prepared. Subsequently, in the intermediate formed body forming step S3, an inclined wall portion 20 is formed in the notched blank B100. Subsequently, in the final formed body forming step S4, a first side wall portion 30 is formed in the notched blank B100. At this time, since there is a notch B50 at a position corresponding to the non-bonded portion in the notched blank B100, the generation of wrinkles that would occur if there were no notch B50 can be suppressed. In addition, in the notched blank B100, since a force in the compression direction acts on a position that becomes the third connection portion (third ridge line) 13 continuous with the notch B50, cracks do not occur either. Therefore, according to this formed body manufacturing method, wrinkles and cracks do not occur between the inclined wall portion 20 and the first side wall portion 30.

[0090] In this embodiment, the notch B50 is formed in the rectangular blank in the notched blank preparation step S1. However, the timing for forming the notch B50 may be changed as follows, for example. That is, the method for manufacturing a molded body in this case performs a preparation step, an intermediate molded body forming step (second region portion forming step), a notch forming step, and a final molded body forming step (third region portion forming step). In the preparation step, a rectangular blank without the notch B50 is prepared. This blank has a main wall corresponding portion (first region corresponding portion) B10 corresponding to the main wall portion (first region portion) 10, an inclined wall corresponding portion (second region corresponding portion) B20 corresponding to the inclined wall portion (second region portion) 20, a first side wall corresponding portion (third region corresponding portion) B30 corresponding to the first side wall portion (third region portion) 30, and a second side wall corresponding portion (fourth region corresponding portion) B40 corresponding to the second side wall portion (fourth region portion).

[0091] In the intermediate molded body forming step (second region portion forming step), as in the above embodiment, the inclined wall corresponding portion W20 is inclined to the one side with respect to the main wall corresponding portion W10. After that, the blank is once taken out from the mold D100. In the notch forming step, a notch B50 corresponding to the non-bonded portion is formed at a position between the inclined wall corresponding portion W20 and the first side wall corresponding portion W30 in the blank taken out from the mold D100. In the final molded body forming step (third region portion forming step) S4, as in the above embodiment, while fixing the inclination of the inclined wall corresponding portion W20 with respect to the main wall corresponding portion W10, the first side wall corresponding portion W30 is relatively moved toward the one side with respect to the main wall corresponding portion W10. Also with this method for manufacturing a molded body, wrinkles and cracks do not occur between the inclined wall portion 20 and the first side wall portion 30.

[0092] <Molding condition setting method> Next, with reference to FIGS. 11 to 13, a procedure for setting the molded body with notch B100 according to this embodiment, the molding conditions for the draw bead D50, the configuration of the molded body with notch B100, and the configuration of the draw bead D50 will be described.

[0093] Hereinafter, with reference to FIG. 11, an example of a method for setting molding conditions will be described. FIG. 11 is a flowchart for explaining an example of a molding condition setting procedure.

[0094] First, configure the dashboard 100, the notched blank B100, the first press molding conditions, the draw bead D50, and the second press molding conditions (step S11). Here, as the configuration of the dashboard 100, for example, the three-dimensional shape, material properties, wall thickness (or wall thickness distribution), etc. of the dashboard 100 are targeted. The wall thickness of the dashboard 100 can be substituted, for example, with the plate thickness of the notched blank B100. As the material properties, for example, Young's modulus, yield strength (proof stress), and the relationship between stress and strain in a tensile test (stress-strain curve, etc.) are targeted. When the material properties are known, instead of the material properties, the material type of the metal material, etc. may be set. As the configuration of the notched blank B100, the plate thickness of the steel plate (metal plate), steel type (material), outer shape (excluding the notch W50), and the configuration of the notch W50 (for example, shape, arrangement, etc.) are targeted.

[0095] As the first press molding conditions, for example, the three-dimensional shape, etc. for the mold D100 to form the intermediate molded product W100 in the intermediate molded product forming process are targeted. As the configuration of the draw bead D50, in the final molded product forming process, when the mold D100 forms the dashboard 100 from the intermediate molded product W100, the three-dimensional shape for forming the dashboard 100 and the clamping state with respect to the second side wall corresponding portion W40 (for example, the arrangement of the draw bead D50, the width, height, cross-sectional shape, etc. of the draw bead D50) are targeted. As the second press molding conditions, the three-dimensional shape of the mold D100 used in the final molded product forming process and the shape change of the second side wall corresponding portion W40 when forming the dashboard 100 from the intermediate molded product W100 are targeted. In addition, various conditions may be added to the configuration of the dashboard 100, the configuration of the notched blank B100, the first press forming conditions, the configuration of the draw bead D50, and the second press forming conditions as required. Also, the content of each setting condition can be arbitrarily set as required. After performing step S11, proceed to step S12.

[0096] Next, calculate the configuration of the intermediate formed product W100 (step S12). The configuration of the intermediate formed product W100 is calculated using the finite element method, for example, based on the configuration of the notched blank B100 and the first press forming conditions in the intermediate formed body forming process. As the configuration of the intermediate formed product W100, for example, the three-dimensional shape of the intermediate formed product W100, the shape, position, etc. of the forming notch W50 in the intermediate formed product W100 are targeted. Note that when calculating the configuration of the intermediate formed product W100, the configuration of the intermediate formed product W100 may be calculated by a method other than the finite element method, such as calculation based on experimental results, instead of the finite element method. After performing step S12, proceed to step S13.

[0097] Next, calculate the stress in the first side wall corresponding portion W30 of the dashboard 100 (step S13). The stress generated in the first side wall corresponding portion W30 when forming the dashboard 100 in the final formed body forming process is calculated using the finite element method, for example, based on the configuration of the intermediate formed product W100, the configuration of the dashboard 100, the configuration of the draw bead D50, and the second press forming conditions. The calculation of the stress in the first side wall corresponding portion W30 is, for example, from the configuration of the intermediate formed product W100 and the configuration of the draw bead D50, when the mold D100 forms the dashboard 100 from the intermediate formed product W100 in the final formed body forming process, calculate the material flow from the contact (pressing) order of the mold D100 with respect to the intermediate formed product W100, the distribution of the pressing force, and the control state of the material flow by the draw bead D50, and based on the result, calculate the stress distribution in the first side wall corresponding portion W30 of the formed dashboard 100. When calculating the stress in the first side wall corresponding portion W30 of the dash panel 100, the stress generated in the first side wall corresponding portion W30 may be calculated by a method other than the finite element method, such as calculation based on experimental results, instead of the finite element method. After performing step S13, proceed to step S14.

[0098] Next, evaluate the stress of the first side wall corresponding portion W30 in the dash panel 100 (step S14). The stress evaluation of the first side wall corresponding portion W30 is performed based on whether "the stress of the first side wall corresponding portion W30 ≤ the set compressive stress". If "the stress of the first side wall corresponding portion W30 ≤ the set compressive stress" (step S14: Yes), set the molding conditions set in step S11 and end the flowchart. Also, if "the stress of the first side wall corresponding portion W30 ≤ the set compressive stress" is not satisfied (step S14: No), proceed to step S15.

[0099] Review the configuration of the notched blank B100 and the configuration of the draw bead D50 (step S15). When reviewing the configuration of the notched blank B100 and the configuration of the draw bead D50, either the configuration of the notched blank B100 or the configuration of the draw bead D50, or both the configuration of the notched blank B100 and the configuration of the draw bead D50 may be reviewed in consideration of the stress distribution etc. of the first side wall corresponding portion W30. After performing step S15, proceed to step S11. Repeat the above steps S11 to S15.

[0100] Note that the above method of setting the molding conditions is premised on the fact that both the configuration of the notched blank B100 and the configuration of the draw bead D50 can be reviewed. However, as in the following modification example, it is also possible to set the molding conditions on the premise of reviewing only one of the configuration of the notched blank B100 and the configuration of the draw bead D50.

[0101] <Configuration setting of the notched blank B100> Next, with reference to FIG. 12, an example of a procedure for setting (fixing) the configuration of the draw bead D50 in advance and determining the configuration of the notched blank B100 suitable for the draw bead D50 will be described. FIG. 13 is a flowchart showing an example of a procedure for determining the configuration of the notched blank B100 after setting the configuration of the draw bead D50 in advance according to the first embodiment.

[0102] Steps S21 to S25 in the flowchart shown in FIG. 12 respectively correspond to S11 to S15 in the flowchart shown in FIG. 11. As a difference between the two, when setting each condition in step S21, first, the configuration of the notched blank B100 is set as a provisional configuration, and the configuration of the draw bead D50 is set as a fixed configuration. After that, when step S24 is No and the process proceeds to step S25, only the configuration of the notched blank B100 is reviewed, and the configuration of the draw bead D50 is not reviewed.

[0103] <Configuration setting of the draw bead D50> Next, with reference to FIG. 13, an example of a procedure for setting (fixing) the configuration of the notched blank B100 in advance and determining the configuration of the draw bead D50 according to the configuration of the notched blank B100 will be described. FIG. 13 is a flowchart showing an example of a procedure for determining the configuration of the draw bead D50 after setting the configuration of the notched blank B100 in advance according to the first embodiment.

[0104] Steps S31 to S35 in the flowchart shown in FIG. 13 respectively correspond to S11 to S15 in the flowchart shown in FIG. 11. As a difference between the two, when setting each condition in step S31, first, the configuration of the draw bead D50 is set as a provisional configuration, and the configuration of the notched blank B100 is set as a fixed configuration. After that, when it becomes "No" in step S34 and the process proceeds to step S35, only the configuration of the draw bead D50 is reviewed, and the configuration of the notched blank B100 is not reviewed.

[0105] According to the dash panel 100 and the molded body manufacturing method according to the present embodiment, in the notched blank forming step, a notched blank B100 in which a notch B50 is formed is prepared. In the intermediate molded body forming step (second region portion forming step), an intermediate molded product W100 is formed from the notched blank B100. In the molded body forming step (third region portion forming step), when the dash panel 100 is molded by holding the main wall corresponding portion W10 and the inclined wall corresponding portion W20 of the intermediate molded product W100 and relatively moving the first side wall corresponding portion W30 of the intermediate molded product W100 downward with respect to the main wall corresponding portion W10, the first side wall corresponding portion W30 is pinched by the draw bead D50 and a material flow toward the notch W50 is generated in the first side wall corresponding portion W30. Therefore, it is possible to suppress the generation of compressive stress in the first side wall corresponding portion W3030 and suppress the occurrence of out-of-plane deformation such as wrinkles in the first side wall portion 30. As a result, the dash panel 100 can be manufactured efficiently and stably while ensuring a desired quality. In addition, the strength of the dash panel 100 (product) that is difficult to perform ironing forming can be efficiently improved.

[0106] Also, according to the dash panel 100 and the molded body manufacturing method according to the present embodiment, in the molded body forming step, even when a surplus of material occurs when the first side wall corresponding portion W30 of the intermediate molded product W100 is formed into the concave curved surface wall portion 30A, since the edge portion on the first side wall corresponding portion W30 side of the notch W50 is displaced in the direction of arrow T50, it is possible to suppress the occurrence of out-of-plane deformation such as wrinkles and the generation of compressive stress in the first side wall corresponding portion W30.

[0107] Also, according to the dash panel 100 and the molded body manufacturing method according to the present embodiment, in the molded body molding step, the compressive stress generated in the first side wall corresponding portion W30 of the intermediate molded product W100 is controlled to be equal to or less than a predetermined value (for example, the compressive stress at which wrinkles are formed (allowable compressive stress)). Therefore, the quality of the first side wall portion 30 of the dash panel 100 can be surely ensured.

[0108] Also, according to the dash panel 100 and the molded body manufacturing method according to the present embodiment, since the notch W50 is removed in a subsequent process, the dash panel 100 is configured not to remain when it is distributed as a product or a component. Therefore, the degree of freedom in designing the dash panel 100 can be improved, and the performance and strength of the product or component can be fully exhibited.

[0109] Also, according to the dash panel 100 and the molded body manufacturing method according to the present embodiment, the dash panel 100 made of a high-tensile steel plate with a tensile strength of 980 MPa or more can be stably molded, which is difficult to form by drawing.

[0110] Also, according to the molding condition setting method according to the present embodiment, by calculating the material flow in the first side wall corresponding portion W30, the configuration of the notched blank B100 and the configuration of the draw bead D50 can be efficiently determined.

[0111] Also, according to the method for setting the configuration of the notched blank B100 according to the present embodiment, the configuration of the notched blank B100 is determined by calculating the material flow in the first side wall corresponding portion W30 based on the predetermined configuration of the draw bead D50. Therefore, the configuration of the notched blank B100 can be efficiently determined.

[0112] Also, according to the method for setting the configuration of the draw bead D50 according to the present embodiment, the configuration of the draw bead D50 is determined by calculating the material flow in the first side wall corresponding portion W30 based on the predetermined configuration of the notched blank B100. Therefore, the configuration of the draw bead D50 can be efficiently determined.

[0113] <Second Embodiment> Hereinafter, with reference to FIG. 14, a second embodiment of the present invention will be described. FIG. 14 is a flowchart for explaining an outline of a molded body manufacturing process according to the second embodiment.

[0114] As shown in FIG. 14, the molded body manufacturing process according to the present embodiment includes a notched blank preparation step (step S101), an intermediate molded body forming step (second region portion forming step) (step S102), and a molded body forming step (third region portion forming step) (step S103). "Set notched blank", "Set intermediate molded product", and "Take out molded body" shown in FIG. 14 indicate handling in the intermediate molded body forming step (step S102) and the molded body forming step (step S103), respectively.

[0115] In the molded body manufacturing process according to the present embodiment, when manufacturing the dash panel 100, a mold D100 that molds the intermediate molded body forming step and the final molded body forming step at the same station is used. On the other hand, a first press molding die that forms an intermediate molded product W100 from a notched blank B100 in the first molding step and a second press molding die that forms a dash panel 100 from the intermediate molded product W100 in the second molding step are prepared. The intermediate molded product W100 is formed by the first press molding die, the intermediate molded product W100 taken out from the first press molding die is set in the second press molding die, and press molding (pad drawing molding) is performed by the second press molding die to form the dash panel 100.

[0116] The first press molding die includes a molded shape portion that has finished forming the intermediate molded product W100 in the intermediate molded body forming step according to the first embodiment. In addition, the second press molding die includes a molded shape portion and functions used when forming the dash panel 100 from the intermediate molded product W100 in the molded body forming step according to the first embodiment. The rest is the same as the first embodiment, so the description is omitted.

[0117] <Third Embodiment> Hereinafter, with reference to FIGS. 15, 16A to 16D, a third embodiment of the present invention will be described. FIG. 15 is a perspective view for explaining a method for manufacturing a molded body using the mold according to this embodiment. FIGS. 16A to 16D are perspective views for explaining the first region forming step to the fourth region forming step in the method for manufacturing a molded body using the mold according to the third embodiment. In the mold D500 according to this third embodiment, the same components as those in the mold D100 according to the first embodiment are denoted by the same reference numerals, and the description thereof is omitted, and only the different points will be described.

[0118] The mold D500 of this embodiment is attached to a press molding device (not shown) to constitute a molded body manufacturing device. As shown in FIG. 15, the mold D500 includes an upper mold U500 and a lower mold L100 that can move relative to the upper mold U500 along the arrow UD direction. The mold D500 is a mold for manufacturing the dash panel (molded body) 100 shown in FIG. 1 from the notched blank B100 shown in FIG. 4.

[0119] Similar to the mold D100 according to the first embodiment, the lower mold L100 includes a holder L101 and lower pads L102 and L103.

[0120] The upper mold U500 includes an upper pad U501 and dies U102 and U103. The dies U102 and U103 have the same configuration as those of the mold D100 according to the first embodiment. On the other hand, the upper pad U501 includes a leading pad U501A having a pad bottom surface U101a and a trailing pad U501B having a pad inclined surface U101b. These leading pad U501A and trailing pad U501B can move up and down independently of each other. In the mold D100 according to the first embodiment, since the upper pad U101 was integral, the configurations of the upper pads U101 and U501 are different between the mold D100 and the mold D500.

[0121] When manufacturing the dashboard 100 from the notched blank B100 using this mold D500, basically, in the same manner as the manufacturing method according to the first embodiment, (1) the notched blank preparation step S1, (2) the notched blank setting step S2, (3) the intermediate molded body forming step S3, and (4) the final molded body forming step S4 are carried out. However, similar to the manufacturing method according to the first embodiment, it is also possible to set the timing for forming the notch B50 between the intermediate molded body forming step S3 and the final molded body forming step S4. Hereinafter, regarding the manufacturing method according to this embodiment, the main differences from the first embodiment will be mainly described.

[0122] In the manufacturing method according to this embodiment, in the (2) notched blank setting step S2, as shown in FIG. 15, in the upper mold U500, the leading pad U501A may be positioned below (towards the lower mold L100) with respect to the trailing pad U501B.

[0123] Thereafter, in the (3) intermediate molded body forming step S3, by moving the leading pad U501A towards the holder L101, as shown in FIG. 16A, the main wall corresponding portion B10 is sandwiched and fixed between the holder L101 and the leading pad U501 (blank fixing step). Subsequently, the trailing pad U501B is moved towards the holder L101. As a result, as shown in FIG. 16B, the main wall portion 10 and the inclined wall portion 20 are formed on the notched blank B100. Next, the combination of the dies U102, U103 is moved towards the combination of the lower pads L102, L103. As a result, as shown in FIG. 16C, the second side wall corresponding portion B40 is sandwiched between the top surfaces L102a, L103a of the pads and the first bottom surfaces U102a, U103a of the dies.

[0124] Thereafter, in the (4) final molded body forming step S4, as shown in FIG. 16D, the combination of the lower pads L102, L103 and the dies U102, U103 is relatively moved toward the one side with respect to the combination of the holder L101 and the upper pad U501 (third region portion forming step). Thereby, the first side wall portion 30 and the second side wall portion 40 are formed.

[0125] <Fourth Embodiment> Hereinafter, with reference to FIGS. 17 to 20, a fourth embodiment of the present invention will be described. FIG. 17 is a perspective view for explaining a molded body manufacturing method using the mold according to the present embodiment. FIGS. 18 to 20 are diagrams for explaining the molded body manufacturing method using the mold according to the present embodiment. In the mold D600 according to the fourth embodiment, the same components as those in the mold D500 according to the third embodiment are denoted by the same reference numerals, and the description thereof is omitted, and only the differences will be described.

[0126] The mold D600 of the present embodiment is mounted on a press molding device (not shown) to constitute a molded body manufacturing device. The mold D600 includes an upper mold U500 and a lower mold L600 that is relatively movable along the arrow UD direction with respect to the upper mold U500, as shown in FIG. 17. The mold D600 is a mold for manufacturing the dash panel (molded body) 100 shown in FIG. 1 from the notched blank B100 shown in FIG. 4.

[0127] The upper mold U500 includes an upper pad U501 and dies U102, U103, similar to the mold D500 according to the third embodiment. However, the upper pad U501 may have the same configuration as the upper pad U101 of the mold D100 according to the first embodiment (that is, the upper pad may not be divided into a preceding pad U501A and a following pad U501B).

[0128] The lower mold L600 includes a holder L601 and lower pads L102 and L103. The lower pads L102 and L103 have the same configuration as the mold D100 according to the first embodiment. On the other hand, the holder L601 includes a blank holder L601A having a holder top surface L101a and a punch L601B that is disposed adjacent to the blank holder L601A and has a holder second inclined surface L101c. The blank holder L601A and the punch L601B can move up and down independently of each other. In this embodiment, the blank holder L601A further includes a holder first inclined surface L101b. Also, in this embodiment, a pair of punches L601B are provided symmetrically with the blank holder L601A interposed therebetween. In the mold D500 according to the third embodiment, since the holder L101 was integral, the configurations of the holders L101 and L601 are different between the mold D500 and the mold D600.

[0129] When manufacturing the dash panel 100 from the notched blank B100 using this mold D600, basically, similar to the manufacturing methods according to the first embodiment and the third embodiment above, (1) the notched blank preparation step S1, (2) the notched blank setting step S2, (3) the intermediate formed body forming step S3, and (4) the final formed body forming step S4 are carried out. However, similar to the manufacturing methods according to the first embodiment and the third embodiment above, it is also possible to set the timing for forming the notch B50 between the intermediate formed body forming step S3 and the final formed body forming step S4. Hereinafter, the manufacturing method according to this embodiment will be described mainly focusing on the main differences from the third embodiment above.

[0130] In the manufacturing method according to this embodiment, in the (3) intermediate molded body forming step S3, as shown in FIG. 18, the combination of the pads U501 (preceding pad U501A and following pad U501B) and the dies U102, U103 is moved toward the combination of the holder L601 and the lower pads L102, L103. As a result, the main wall portion 10 and the inclined wall portion 20 are formed on the notched blank B100, and the second side wall corresponding portion B40 is sandwiched between the top surfaces L102a, L103a of the pads and the first bottom surfaces U102a, U103a of the dies. At this time, the punch L601B is disposed below the blank holder L601A.

[0131] Thereafter, in the (4) final molded body forming step S4, as shown in FIG. 19, the combination of the lower pads L102, L103 and the dies U102, U103 is relatively moved toward the one side (downward) with respect to the combination of the blank holder L601A and the upper pad U501. Also, as shown in FIG. 20, the punch L601B is relatively moved in a direction opposite to the one side (upward) with respect to the blank holder L601A and the upper pad U501. As a result, the first side wall corresponding portion W30 of the notched blank B100 is sandwiched between the second inclined surface L101c of the holder and the second bottom surfaces U102b, U103b of the dies. Thereby, the first side wall portion 30 and the second side wall portion 40 are formed.

[0132] Note that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the invention.

[0133] For example, in the above-described embodiment, the case where the molded body is the dash panel 100 has been described, but the present invention is applicable to various other products and components. Further, convex shapes, concave shapes, holes, etc. may be formed in the main wall portion 10 and the inclined wall portion 20 of the dash panel 100. Further, holes or the like may be formed in the notched blank B100.

[0134] In the above-described embodiment, the case where the concave curved wall portion 30A that bulges toward the opposite side of the bend on the extension of the first connection portion corresponding portion W11 formed in the first side wall corresponding portion W30 of the intermediate molded product W100 is molded has been described. However, whether to mold it into a dome-shaped wall portion can be arbitrarily set, and it can be applied to various dash panels 100 where surplus material is generated when molding the first side wall corresponding portion W30. Further, it may be applied to a dash panel 100 where no surplus material is generated. That is, whether the dash panel 100 includes a dome-shaped wall portion and what three-dimensional shape the first side wall portion 30 has can be arbitrarily set.

[0135] In the above-described embodiment, the case where the mold D100 moves forward and backward in a direction orthogonal to the main wall portion 10 to mold the dash panel 100 has been described. However, the direction in which the mold D100 moves forward and backward (relatively moves) with respect to the main wall portion 10 can be arbitrarily set. For example, the mold D100 may move in a direction inclined with respect to the orthogonal direction with respect to the main wall portion 10 to mold the intermediate molded product and the dash panel 100.

[0136] In the above-described embodiment, in the dash panel 100 shown in FIG. 1, the portion indicated by hatching is removed in a subsequent process. However, it is not limited to this form, and the second side wall portion 40 and the notch 50 may be left as parts.

[0137] In the above-described embodiment, the case where the flowcharts shown in FIGS. 11 to 13 are applied when setting the molding conditions, the configuration of the notched blank B100, and the configuration of the draw bead D50 has been described. However, the flowcharts shown in FIGS. 11 to 13 are examples, and the setting procedure can be arbitrarily set as necessary. Further, the setting conditions to be set and the content of the setting conditions can be appropriately set.

[0138] In the above embodiment, when setting the forming conditions, configuring the notched blank B100, and configuring the draw bead D50, the configuration of the intermediate formed product and the stress in the first side wall portion 30 of the dash panel 100 were described in the case of calculating using the finite element method. However, for example, it may be calculated by a method other than the finite element method such as calculation by experiment. In the first embodiment above, the case of plastic working by pad drawing forming was described. However, it may be applied to various press forming dies having the same action as the present invention.

[0139] In the above embodiment, when forming the intermediate formed product W100 by the mold D100, the case where the upper mold U100 advances with respect to the lower mold L100 was described. However, for example, the lower mold L100 may rise with respect to the upper mold U100, or the upper mold U100 and the lower mold L100 may be configured to move relative to each other.

[0140] In the above embodiment, when forming the dash panel 100 by the mold D100, the case where the lower pads L102, L103 and the dies U102, U103 descend with respect to the holder L101 and the upper pad U101 was described. However, for example, the holder L101 and the blank holder may rise with respect to the lower pads L102, L103 and the dies U102, U103, or the lower pads L102, L103 and the dies U102, U103 and the holder L101 and the upper pad U101 may be configured to move relative to each other.

Industrial Applicability

[0141] According to this invention, a formed body with cracks and wrinkles suppressed can be provided. Further, according to this invention, a blank, a formed body manufacturing method, and a mold for obtaining the formed body can also be provided. Therefore, the industrial applicability is great.

Explanation of Signs

[0142] 100 Dash panel (formed body) 10 Main wall portion (first region portion) 11 First connecting part 12 Second connecting part 13 Third connecting part 20 Inclined wall part (second region part) 30 First side wall part (third region part) 40 Second side wall part (fourth region part) 50, B50 Notch B100 Notched blank D100, D500 Dies L100, L500 Lower dies L101 Holder L102, L103 Lower pads (first pads) U100, U500 Upper dies U101 Upper pad U102, U103 Dies W100 Intermediate formed product

Claims

1. A molded body extending along a plane defined by an X-axis and a Y-axis orthogonal to each other, having a first ridge line and a second ridge line arranged with a corner therebetween, the first ridge line being an edge in the X-axis direction and the second ridge line being an edge in the Y-axis direction, a first region part; arranged with the first region part with the first ridge line interposed therebetween in the X-axis direction, an edge in the X-axis direction being integrally continuous with the first region part via the first ridge line, and a second region part inclined on one side of the front and back surfaces of the first region part; arranged with the first region part with the second ridge line interposed therebetween in the Y-axis direction, an edge in the Y-axis direction being integrally continuous with the first region part via the second ridge line, and being partially and integrally continuous with the second region part via a third ridge line continuous with the corner, and a third region part inclined on the one side with respect to the first region part; comprising: the first ridge line, the second ridge line, and the third ridge line being connected to each other at the corner; the total length of the outer contour line formed by the first region part and the third region part is L1 (mm), the total length of the outer contour line formed by the second region part and the third region part is L2 (mm), and the following (Equation 1) is satisfied; when the side where the first region part is located with respect to the second region part is defined as the first side in the X-axis direction, and the side where the second region part is located with respect to the first region part is defined as the second side in the X-axis direction, the total length L1 is the sum of the length L11 in the Y-axis direction of the edge on the first side of the first region part and the length L12 in the Y-axis direction of the edge on the first side of the third region part; and the total length L2 is the sum of the length L21 in the Y-axis direction of the edge on the second side of the second region part and the length L22 in the Y-axis direction of the edge on the second side of the third region part; the total length of the adjacent portion along the extension direction of the third ridge line between the second region part and the third region part is L3 (mm), and the length of the non-jointed portion obtained by subtracting the length of the third ridge line from the total length L3 is L4 (mm), and the following (Equation 2) is satisfied. A molded body characterized by the above. L1 > 1.1 × L2... (Equation 1) 0.8 × L3 < L4 < 0.9 × L3... (Equation 2)

2. Comprising a steel plate with a tensile strength of 980 MPa or more The molded body according to claim 1, characterized in that.

3. The plate thickness is 0.8 mm or more and 2.3 mm or less The molded body according to claim 1 or 2, characterized in that.

4. Further comprising a fourth region portion located on the opposite side of the first region portion with the third region portion interposed therebetween and integrally connected to the third region portion via a fourth ridge line, The fourth region portion includes an inclined portion that inclines in the same direction as the second region portion in the arrangement direction from the first region portion toward the second region portion. The molded body according to any one of claims 1 to 3, characterized in that.

5. A flat blank formed into the molded body according to any one of claims 1 to 4, Having a notch corresponding to the non - joined portion The blank, characterized in that.

6. The blank according to claim 5, characterized in that the separation dimension at the end of the notch is W1 (mm) and satisfies the following Equation 3. W1 > L1 - L2... (Equation 3)

7. A method for manufacturing the molded body according to claim 4, A preparation step of preparing a blank having a first region corresponding portion corresponding to the first region portion, a second region corresponding portion corresponding to the second region portion, a third region corresponding portion corresponding to the third region portion, a fourth region corresponding portion corresponding to the fourth region portion, and a notch corresponding to the non - joined portion, A second region portion forming step of inclining the second region corresponding portion with respect to the first region corresponding portion to the one side, While fixing the inclination of the second region corresponding part with respect to the first region corresponding part, by relatively moving the fourth region corresponding part toward the one side with respect to the first region corresponding part, a third region part forming step of inclining the third region corresponding part toward the one side with respect to the first region corresponding part; A method for manufacturing a molded body, characterized by comprising:

8. The preparation step includes a notch forming step of forming the notch in the blank. The method for manufacturing a molded body according to claim 7, characterized by comprising:

9. A method for manufacturing a molded body according to claim 4, comprising: A preparation step of preparing a blank including a first region corresponding part corresponding to the first region part, a second region corresponding part corresponding to the second region part, a third region corresponding part corresponding to the third region part, and a fourth region corresponding part corresponding to the fourth region part; A second region part forming step of inclining the second region corresponding part on one side of the front and back surfaces of the first region corresponding part; A notch forming step of forming a notch corresponding to the non-bonded part between the second region corresponding part and the third region corresponding part; While fixing the inclination of the second region corresponding part with respect to the first region corresponding part, by relatively moving the fourth region corresponding part toward the one side with respect to the first region corresponding part, a third region part forming step of inclining the third region corresponding part toward the one side with respect to the first region corresponding part; A method for manufacturing a molded body, characterized by comprising:

10. In the third region part forming step, by relatively moving the fourth region corresponding part while restraining it by material flow control means, a material flow from the third region corresponding part toward the notch is formed. The method for manufacturing a molded body according to any one of claims 7 to 9, characterized by comprising:

11. A mold for manufacturing the molded body according to claim 4, comprising a blank including a first region corresponding portion corresponding to the first region portion, a second region corresponding portion corresponding to the second region portion, a third region corresponding portion corresponding to the third region portion, and a fourth region corresponding portion corresponding to the fourth region portion, comprising a first mold and a second mold facing each other, wherein the first mold includes a holder having a first region holder surface on which the first region corresponding portion is disposed, a second region holder surface that is continuous with the first region holder surface and is inclined with respect to the first region holder surface to form the second region portion, and a third region holder surface that is continuous with the first region holder surface and is inclined with respect to the first region holder surface to form the third region portion, and a first pad that is disposed adjacent to the holder and has a fourth region pad surface on which the fourth region corresponding portion is placed, and the second mold includes a second pad having a first region pad surface facing the first region holder surface and a second region pad surface facing the second region holder surface, and a die that is disposed adjacent to the second pad and has a fourth region die surface facing the fourth region pad surface, and is characterized by comprising the above.

12. The mold according to claim 11, wherein the second pad includes a leading pad having the first region pad surface and a trailing pad having the second region pad surface. and is characterized by the above.

13. The mold according to claim 11 or 12, wherein the holder includes a blank holder having the first region holder surface and a punch that is disposed adjacent to the blank holder and has the third region holder surface. and is characterized by the above.

14. A method for manufacturing the molded body using the mold according to claim 11, An arranging step of arranging the blank in the first mold such that the first region corresponding portion is located on the first region holder surface, the second region corresponding portion is located on the second region holder surface, and the fourth region corresponding portion is located on the fourth region pad surface; A second region portion forming step of pressing the second pad against the holder to form the second region portion; A third region portion forming step of pressing the second mold against the first mold with a notch corresponding to the non-bonding portion formed in the blank, sandwiching the first region corresponding portion between the first region holder surface and the first region pad surface, sandwiching the second region corresponding portion between the second region holder surface and the second region pad surface, sandwiching the fourth region corresponding portion between the fourth region pad surface and the fourth region die surface, and relatively moving the first pad and the die toward the one side with respect to the holder and the second pad to form the third region portion; A method for manufacturing a molded body, characterized by comprising the above steps.

15. A method for manufacturing the molded body using the mold according to claim 12, comprising: An arranging step of arranging the blank in the first mold such that the first region corresponding portion is located on the first region holder surface, the second region corresponding portion is located on the second region holder surface, and the fourth region corresponding portion is located on the fourth region pad surface; A second region portion forming step of pressing the second pad against the holder to form the second region portion; A third region portion forming step of pressing the second mold against the first mold with a notch corresponding to the non-bonding portion formed in the blank, sandwiching the first region corresponding portion between the first region holder surface and the first region pad surface, sandwiching the second region corresponding portion between the second region holder surface and the second region pad surface, sandwiching the fourth region corresponding portion between the fourth region pad surface and the fourth region die surface, and relatively moving the first pad and the die toward the one side with respect to the holder and the second pad to form the third region portion; and comprising: In the second region portion forming step, after pressing the leading pad against the holder and sandwiching the first region corresponding portion between the first region holder surface and the first region pad surface, the trailing pad is pressed against the holder to form the second region portion. A method for manufacturing a molded body, characterized by the above.

16. A method for manufacturing the molded body using the mold according to claim 13, An arranging step of arranging the blank on the first mold such that the first region corresponding portion is located on the first region holder surface, the second region corresponding portion is located on the second region holder surface, and the fourth region corresponding portion is located on the fourth region pad surface; A second region portion forming step of pressing the second pad against the holder to form the second region portion; With a notch corresponding to the non-bonded portion formed in the blank, the second mold is pressed against the first mold, and the first region corresponding portion is sandwiched between the first region holder surface and the first region pad surface, the second region corresponding portion is sandwiched between the second region holder surface and the second region pad surface, and the fourth region corresponding portion is sandwiched between the fourth region pad surface and the fourth region die surface. In this state, the first pad and the die are relatively moved toward the one side with respect to the holder and the second pad to form the third region portion. A third region portion forming step; having In the third region portion forming step, with the punch positioned on the one side with respect to the blank holder, the first pad and the die are relatively moved toward the one side with respect to the blank holder and the second pad, and the punch is relatively moved in the direction opposite to the one side with respect to the blank holder and the second pad to form the third region portion. A method for manufacturing a molded body, characterized by the above.

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