KR20170081215A - Press-forming method and method of manufacturing component employing same method, and press-forming device and formed component press-formed using same device - Google Patents

Abstract

[PROBLEMS] To suppress occurrence of wrinkles due to deformation of a shrink flange when a high-strength metal plate is press-formed by a component bent in the longitudinal direction of the component and occurrence of cracks due to deformation of the extension flange.
A press forming method for suppressing the occurrence of wrinkles due to the contraction flange deformation of a component curved in the longitudinal direction having a cross-sectional shape of a U-shape or a hat shape, comprising the steps of: While moving the material from the top plate side to the vertical wall portion while causing the stretch flange deformation to occur on the material while tilting the ridgeline which is the boundary between the top plate portion and the vertical wall portion with respect to the press forming direction, The material that is a part of the blank sandwiched between the molds is rotated so as to move in the longitudinal direction of the part and the rotation thereof is suppressed to cause compressive deformation in the plate surface in the longitudinal direction of the part and occurrence of wrinkles of the material of the flange part and the top plate A press forming room for a curved part characterized by suppressing with a mold It is law.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a press forming method, a method of manufacturing a part using the method, a press forming apparatus, and a molded part formed by press molding using the press forming apparatus. -FORMED USING SAME DEVICE}

The present invention relates to a press forming method for a component curved in the longitudinal direction having a cross-sectional shape of a cross shape or a hat shape, and particularly relates to a press forming method for suppressing cracks caused by deformation of the extension flange, ≪ / RTI > The present invention also relates to a method of manufacturing a component using the press forming method. The present invention also relates to a press forming apparatus for a component curved in the longitudinal direction having a cross-sectional shape of a cross shape or a hat shape, and more particularly to a press forming apparatus for a component that suppresses cracks due to stretch flange deformation and wrinkles caused by shrinkage flange molding The present invention relates to a press forming apparatus. The present invention also relates to a molded part press-molded by using the press molding apparatus.

In recent years, a metal plate having a higher strength has been required in order to make both the collision safety of an automobile and the weight reduction of a vehicle body compatible. However, as the tensile strength of the metal plate is improved, the ductility largely related to the press formability tends to decrease. Therefore, there is a tendency that foam (bending) molding or draw (drawing) molding is more used than extrusion molding in which the ductility of the material greatly affects the moldability.

In the draw forming, first, a blank holding portion is disposed at a position where a flange is attached to a blank, which is a metal plate serving as a material for a part to be molded, and the blank is placed on the punch and the blank holding portion, Install it. Next, by lowering the die, the blank is pressed against the die and the wrinkle suppressing portion, and the blank is bent while applying an appropriate tension to the blank. At this time, the material (a part of the blank) that is greatly drawn between the punch and the die by being pressed by the die and the wrinkle restraining part forms the vertical wall part of the part. Therefore, even if the material is insufficient in ductility, the vertical wall portion can be easily formed. In addition, since the out-plane deformation (wrinkles) of the blank is restrained by the die and the wrinkle restraining portion, it is easy to adjust the tension applied to the material drawn into the vertical wall portion.

On the other hand, when a complicated part shape is manufactured by draw forming, there is a problem that cracks or wrinkles are likely to occur at the end portion of the blank at the position where the flange is attached. Particularly, It is easy to become a problem. 1 (a), 1 (b) and 1 (c) show a front view, a side view and a cross-sectional view along the line AA of FIG. 1 (a), respectively, of a blank shape used for molding a component curved in the longitudinal direction by the conventional method 2 (a), 2 (b) and 2 (c) show examples of shrinkage flange deformation S and elongation flange deformation E that occur when a longitudinally curved part is molded by the conventional method 3 (a) and 3 (b) show cross-sectional views of the mold structure at the AA cross section in FIG. 1 (a) before molding and at the time of molding. In the drawings, reference numeral 1 denotes a die, 2 denotes a punch, 3 denotes a wrinkle suppressing portion, 4 denotes a blank, and 5 denotes a molded part.

The component 5 has a top plate portion 5a, a vertical wall portion 5b and a flange portion 5c. When the vertical wall portion 5b, the flange portion 5c, and the like are curved, (Extension flange deformation) that elongates in the circumferential direction of the curved shape due to an excess or a short of the line length when the material that is a part of the blank 4 moves between the wrinkle restraining portions 3 and deformation (contraction flange deformation ). Cracks are generated when the extension flange deformation to such an extent as to exceed the ductility of the material near the end of the blank 4 and wrinkles are generated when the shrinkage flange deformation is exceeded to exceed the buckling strength of the material. It is easy to become a problem.

As a method for suppressing the wrinkles due to the deformation of the contraction flange, a method of dispersing the contraction flange deformation as in Patent Document 1 is known. As a method for suppressing cracks due to elongation flange deformation, a method of dispersing stretch flange deformation as in Patent Document 2 is known.

Japanese Laid-Open Patent Publication No. 2010-227995 Japanese Laid-Open Patent Publication No. 2014-039957

However, since the stress to be generated with respect to the amount of deformation increases as the strength of the metal plate increases, stress exceeding the buckling strength of the metal plate is liable to occur, and larger wrinkles are generated. In addition, since the strength of the wrinkles increases with the metal plate having a high strength, a method of dispersing the wrinkles as in Patent Document 1 can not provide a sufficient measure. The higher the strength of the metal plate, the lower the ductility of the blank end. Therefore, there is a limit to the crack that can be prevented by dispersion of stretch flange deformation as in Patent Document 2.

As described above, in order to suppress wrinkles and cracks due to the deformation of the shrink flange and the deformation of the extension flange when the high-strength metal plate is press-formed by a component curved in the longitudinal direction of the component, the occurrence of the shrink flange deformation and the stretch flange deformation itself It should be alleviated.

The press molding method of the present invention which solves the above problems advantageously is a method for suppressing the occurrence of wrinkles due to the contraction flange deformation of a component curved in the longitudinal direction having a cross-sectional shape of a cross shape or a hat shape, The material is moved from the side of the top plate to the side of the vertical wall while the stretch flange deformation is generated in the material by suppressing the movement of the material from the flange portion side to the vertical wall portion, Is suppressed by a mold.

Another press molding method of the present invention which solves the above problems advantageously is a method for suppressing the occurrence of cracks due to the extension flange deformation of a component curved in the longitudinal direction having a cross sectional shape of a cross shape or a hat shape, The ridgeline which forms the boundary between the vertical wall portion and the vertical wall portion is inclined with respect to the press forming direction so that the material that is a part of the blank sandwiched between the dies during the draw forming is rotated so as to move in the longitudinal direction of the component, Compressive deformation is generated and generation of wrinkles in the material of the flange portion and the top plate portion is suppressed by the mold.

The method of manufacturing a component of the present invention is characterized in that a component bent in a longitudinal direction having a cross-sectional shape of a chisel or a hat shape is formed from a plate-like blank by using the press molding method of the present invention described above will be.

On the other hand, the press forming apparatus of the present invention which solves the above problems advantageously is a press forming apparatus for suppressing the occurrence of wrinkles due to the contraction flange deformation of a component curved in the longitudinal direction having a cross- Contraction flange deformation restraining means for restricting the movement of the material from the flange portion side of the blank to the vertical wall portion so as to move the material from the top plate side to the vertical wall portion while generating stretch flange deformation in the material, And a wrinkle suppressing means for suppressing the occurrence of wrinkles of the material between the material of the top plate portion and the wrinkle suppressing means.

Another press molding apparatus of the present invention which solves the above problems advantageously is a press molding apparatus for suppressing the occurrence of cracks due to the extension flange deformation of a component curved in the longitudinal direction having a cross sectional shape of a cross shape or a hat shape A ridge line which is a boundary between the top plate portion and the vertical wall portion is inclined relative to the press forming direction to generate a rotational force for moving the material that is a part of the blank held between the dies during draw forming in the longitudinal direction of the component, An extension flange deformation restraining means for causing compressive deformation in the longitudinal direction of the plate surface; and wrinkle suppressing means for suppressing the occurrence of wrinkles of the material between the flange portion and the top plate portion with the material therebetween.

The molded part of the present invention is a part bent in a longitudinal direction having a cross-sectional shape of a cross shape or a hat shape, which is press-formed from a flat blank using the above-described press molding apparatus of the present invention will be.

According to the press forming method and the press forming apparatus of the present invention, when the longitudinal wall portion of a longitudinally curved part having a cross-sectional shape of a cross shape or a hat shape is formed, Unlike the draw forming, since the vertical wall portion is formed by moving the material preferentially from the top plate side, it is possible to avoid the occurrence of deformation of the shrink flange at the flange portion. When the ridgeline which is the boundary between the top plate portion and the vertical wall portion is inclined relative to the press forming direction, the material sandwiched between the metal molds during the draw forming can be rotated so as to move in the longitudinal direction of the component. The deformation of the extension flange can be suppressed. In addition, by using the method of suppressing the shrinkage flange deformation and the method of suppressing deformation of the extension flange, it is possible to simultaneously suppress occurrence of wrinkles and generation of cracks in the flange portion of the component curved in the longitudinal direction. According to the method for producing a part of the present invention using the press forming method of the present invention and the molded part formed by press molding using the press forming apparatus of the present invention, One or both of the occurrence of wrinkles due to the contraction flange deformation and the occurrence of cracks due to the deformation of the extension flange can be suppressed.

In the press forming method and the press forming apparatus of the present invention, the flange portion in which the contraction flange deformation occurs is shared in the single draw forming, and the two parts are simultaneously formed so as to be symmetrical with respect to the flange portion, It is preferable to suppress the movement of the material from the flange portion side to the vertical wall portion. By doing so, the occurrence of wrinkles due to the deformation of the contraction flange can be suppressed with a simple structure.

In the press forming method and the press forming apparatus of the present invention, it is preferable that the surface parallel to the press forming direction is formed on the member of the mold so as to suppress the rotation of the material. By doing so, it is possible to suppress the occurrence of cracks due to the elongation flange deformation with a simple structure.

In the press forming method and the press forming apparatus of the present invention, it is preferable to use the above two press forming methods or two press forming apparatuses in combination. This makes it possible to simultaneously suppress the occurrence of wrinkles and the occurrence of cracks in the flange portion of the component curved in the longitudinal direction.

In the press forming method and the press forming apparatus of the present invention, it is preferable that the wrinkle suppressing pressure for the blank is set to 0.1 to 100 MPa for suppressing the wrinkles caused by the mold, or the gap between the mold and the material It is preferable to maintain the thickness at 0 to 200%.

Further, in the press forming method and the press forming apparatus of the present invention, it is preferable to use a metal plate having a tensile strength of 440 to 1470 MPa as a blank. In this case, one or both of the occurrence of wrinkles due to the deformation of the shrink flange at the time of press forming of the component made of the high-strength metal plate and the occurrence of the crack due to the deformation of the extension flange can be suppressed.

1 (a), 1 (b) and 1 (c) are a front view, a side view, and a side view of a blank shape used for molding a component curved in the longitudinal direction by the conventional method and along the line AA in FIG. 1 Sectional view.
Figs. 2 (a), 2 (b) and 2 (c) are a front view and a side view showing an example of a shrink flange deformation and a stretch flange deformation that occur when a component curved in the longitudinal direction is molded by the conventional method, (a) taken along the line AA.
3 (a) and 3 (b) are cross-sectional views showing the mold structure at the AA cross section in FIG. 1 (a) before molding and at the time of molding.
4 (a), 4 (b) and 4 (c) are a front view, a side view and a side view showing the shape of a blank used for molding a part curved in the longitudinal direction in one embodiment of the press- 4 is a cross-sectional view taken along line AA of Fig.
Figs. 4A, 4B and 4C are a front view, a side view, and a cross-sectional view along the line AA of Fig. 4A (a) showing the shape of an intermediate molded article molded by the press forming method of the embodiment .
Figs. 4A, 4B and 4C are a front view, a side view, and a cross-sectional view along the line AA in Fig. 4B (a) showing the shapes of the components molded by the press forming method of the embodiment.
Figs. 5A and 5B are cross-sectional views of the mold structure taken along line AA in Fig.
Fig. 5B is a cross-sectional view of the mold structure taken along line AA in Fig. 4B before molding and at the completion of molding, in Figs. 5A and 5B.
6 (a), 6 (b) and 6 (c) are a front view and a side view showing the shape of a blank used for the material behavior investigation at the time of draw forming by the present inventors and a sectional view along AA line in FIG. 6 to be.
Figs. 6A, 6B and 6C are a front view, a side view, and a cross-sectional view along the line AA in Fig. 6A (a) showing the shape of an intermediate molded article press-molded in the material behavior investigation.
Figs. 6A, 6B and 6C are a front view, a side view, and a cross-sectional view along the line AA in Fig. 6B (a) showing the shape of the press-molded part in the material behavior investigation.
7 (a), 7 (b) and 7 (c) are a front view, a side view, and a side view showing the shape of a blank used for molding a component curved in the longitudinal direction in another embodiment of the press- 7 is a cross-sectional view taken along line AA of Fig. 7 (a).
Figs. 7A, 7B and 7C are a front view, a side view, and a cross-sectional view along the line AA of Fig. 7A (a) showing the shape of the intermediate molded article molded by the press forming method of the embodiment .
Figs. 7A, 7B and 7C are a front view, a side view, and a cross-sectional view along the line AA of Fig. 7B (a) showing the shapes of the components molded by the press forming method of the embodiment.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings based on the drawings. Here, Figs. 4 (a), 4 (b) and 4 (c) are cross-sectional views of a blank used for molding a part curved in the longitudinal direction in one embodiment of the press- (A), 4 (a), 4 (b), and 4 (c) of FIG. 4 are cross sectional views taken along the line AA of FIG. 4 (A), Fig. 4 (b) and Fig. 4 (b) are cross-sectional views taken along the line AA in Fig. 4 , A front view, a side view, and a cross-sectional view along the line AA of Fig. 4B (a) showing the shapes of parts molded by the press forming method of the above embodiment. 5A and 5B are cross-sectional views showing the mold structure at the AA section in FIG. 4A (a) before molding and at the time of molding, and FIGS. 5A and 5B are cross- (B) of FIG. 4 (b) is a cross-sectional view of the mold structure taken along line AA in FIG. 4 (b) before and after molding. The same parts as those in the conventional example are denoted by the same reference numerals.

The inventor of the present invention has repeatedly studied various methods for preventing wrinkles caused by contraction flange deformation. At this time, since the contraction flange deformation occurs when the line length remains when the material moves from the flange portion side to the vertical wall portion, it has been considered that the same vertical wall portion can not be formed due to the extension flange deformation which is insufficient in the line length. Then, it is conceived that the moving direction of the material for forming the vertical wall portion can be reversed. In other words, when the vertical wall portion is formed from the top plate side rather than the flange portion side, wrinkles are not generated in the flange portion. In addition, since the position where stretch flange deformation occurs is located on the side of the top plate remote from the end of the blank, cracks due to stretch flange deformation do not occur well.

Figs. 4, 4A and 4B show examples of countermeasures against shrinkage flange deformation based on the embodiment of the present invention, and the structure of a mold as a press molding apparatus in the section along the line AA is shown in Figs. 5A and 5B 5b. The press forming direction is a direction perpendicular to the paper surface with respect to the front view. In order to restrain the movement of the material at the position B where the contraction flange deformation is caused by the conventional method, as shown in Figs. 4A to 4B, the flange portion in which the contraction flange deformation occurs is shared, The two parts 5 may be simultaneously molded so as to be symmetrical with each other. As a result, as shown in Fig. 4A, the movement of the material from the top plate side can be generated preferentially, and the elongation flange deformation E is generated by extending the line length of the material. Then, in the next step, as shown in Fig. 4B, when the outer flange portion is molded, two parts bent in the longitudinal direction in which the shrink flange deformation is suppressed are completed. That is, this configuration in which two of these parts of the mold are taken corresponds to the contraction flange deformation restricting means.

In the process of Fig. 4B, when the vertical wall portion and the top plate are curved in the longitudinal direction of the component, the material moves to the vertical wall portion nonuniformly. Therefore, in order to suppress unnecessary in- . Further, since the flange portion serves as a joint portion with other parts, it is preferable to prevent the out-of-plane deformation by the metal mold. Specifically, the top plate portion is placed between the punch 2 and the pad 7, and the flange portion side is placed between the die 1 and the wrinkle restraining portion 3 so that the material can be moved. In the process of Fig. 4B, contraction flange deformation occurs when the material moves from the top plate side to the vertical wall portion during draw forming, which may cause wrinkles. Therefore, the material of the top plate portion is placed between the punch 2 and the pad 7 as described above, and the flange side is placed between the die 1 and the wrinkle restraining portion 3 so that the material can be moved. That is, the constitution in which these materials of the mold are interposed is equivalent to the wrinkle suppression means.

Further, in the press forming method of the present invention, the method of restricting the movement of the material at the position B where the contraction flange deformation occurs by the conventional method is not limited to the example of Fig. 4B, It is also possible to use a deformation resistance of a metal plate by placing a metal plate between the metal molds in which the concavo-convex shapes such as beads and embosses are formed, in addition to the resistance.

Next, the inventors of the present invention have repeatedly studied various countermeasures against cracks due to elongation flange deformation. At this time, it has been found that the characteristic change as shown in Fig. 6 is seen in the behavior of the material during draw forming by applying the curvature in the longitudinal direction of the part to the part formed in the direction in which the height of the part changes.

6A, 6B and 6C are a front view and a side view showing the shape of a blank used in the material behavior investigation at the time of draw forming by the present inventor and FIGS. (A), 6 (a), 6 (b) and 6 (c) of FIG. 6 are a front view and a side view showing the shape of an intermediate molded product press- 6A, 6B, 6B and 6C are a front view and a side view showing the shape of a press-molded part in the material behavior investigation. Fig. 6A is a cross- And FIG. 6B is a cross-sectional view taken along line AA of FIG. 6A.

As a result of investigating the result of the above-described material behavior investigation, a ridge line which is a boundary between the top plate portion and the vertical wall portion is formed in the press forming direction (the vertical direction of the front view and the left- It is possible to rotate the material of a part of the blank 4 to move in the longitudinal direction of the part (in the direction of the thick arrow in Figs. 6A and 6B) during the draw forming, by inclining the inclined distance C in FIG. The rotation amount changes by the inclination angle with respect to the press forming direction and the direction of rotation changes in the moving direction of the material for forming the vertical wall portion. Therefore, when the moving direction of the material changes from the movement (the first process) of the top plate side as shown in FIG. 6A to the movement (the second process) of the flange side as shown in FIG. 6B, the direction of rotation is reversed.

Figs. 7 (a), 7 (b) and 7 (c) are cross-sectional views showing another embodiment of the press forming method according to the present invention, in which the shape of a blank used for forming a component curved in the longitudinal direction (A), 7 (a), 7 (a), 7 (b) and 7 (c) of FIG. 7 are cross-sectional views taken along the line AA of FIG. 7 (A), 7 (b), and 7 (b) and 7 (c) are cross-sectional views taken along the line AA of Fig. 7 Fig. 7B is a front view, a side view, and a cross-sectional view along the line AA of Fig. 7B (a) showing the shapes of the components molded by the press forming method of Fig.

The inventors of the present invention have conceived the press forming method of the embodiment of the present invention, which can suppress both the contraction flange deformation and the stretch flange deformation as shown in Figs. 7 to 7B using the above knowledge. In this embodiment, the plate 8 of the metal is pressed against the blank 4 of the press-formed metal mold. In this case, Or the intermediate molded product 6 in the longitudinal direction of the component. This plate 8 of the mold corresponds to a stretch flange deformation restricting means.

7A and 7B, it is sufficient to form not only the metal plate 8 but also the abutment surface parallel to the press forming direction on the metal mold, It is excellent in cost. This abutting surface is slid and contacted with the end face of the blank 4 or the intermediate molded product 6 during draw forming so that it is prevented from being cut by using a material harder than the material of the blank 4, It is preferable to have a structure in which the surface can be exchanged.

According to the press forming method and the press forming apparatus of the present invention, not only the longitudinally curved part having the hat-shaped cross-sectional shape but also the material located at the flange part are used for forming the vertical wall, Parts can also be produced.

The wrinkle suppression pressure is preferably 0.1 to 100 MPa for suppressing wrinkles caused by the mold. When the pressure is less than 0.1 MPa, it is difficult to suppress the out-of-plane deformation (wrinkles) of the blank 4, and a pressure exceeding 100 MPa requires a high-rigidity pressurizing device. When the wrinkle restraining pressure is not used, it is preferable to maintain the gap between the mold and the metal plate of the blank 4 or intermediate mold 6 at 0 to 200% of the plate thickness during molding of the vertical wall portion. There is no particular advantage in setting the gap to less than 0% of the plate thickness, and on the contrary, excessive force is applied to the mold, which may cause wear and deformation of the mold. On the other hand, if the gap is larger than 200%, the wrinkles generated become large, and it becomes difficult to remove the wrinkles in the subsequent trimming process.

The metal plate used as the blank 4 preferably has a tensile strength of 440 to 1470 MPa. A metal plate having a tensile strength of less than 440 MPa is excellent in ductility and drawing moldability and therefore has a small advantage of using the method of the present invention. In addition, since the metal plate having a thickness of more than 1470 MPa is insufficient in ductility, cracks tend to occur in the punch shoulder portion or the die shoulder portion which is not the object of the present invention, and the component can not be molded.

The steel sheet of 270, 440, 980, 1180 and 1470 MPa shown in Table 1 was used as a specimen, and the result of molding was evaluated by the draw-forming method shown in Fig. 2 in the conventional method. The molding results were evaluated by the development method A of the molding of the process and the development method B of the molding of the two steps shown in Figs. 7 to 7B. The metal plate was pressed by a mold at 10 MPa. The evaluation results are shown in Table 2. The evaluation of the molded article was carried out visually, and the wrinkles and cracks occurring in the flange portion were evaluated in four stages of?,?, And?. A case in which significant wrinkles and cracks occurred was indicated by X, a case where slight wrinkles and necking occurred was indicated by DELTA, and a case where no wrinkles, cracks or necking occurred was evaluated as & cir &

In the 270 MPa grade steel sheet, the development method A and B could be formed without causing wrinkles or cracks even in the conventional method. In the case of the steel sheet of 440 MPa class, remarkable wrinkles occurred in the conventional method, but wrinkles were prevented in the development methods A and B. Necking was observed in the conventional method and development method A for crack evaluation, but no crack nor necking occurred in development method B. For the 980, 1180 and 1470 MPa grade steel, wrinkles observed in the conventional method were not observed in development methods A and B. As for crack evaluation, cracks occurred in the conventional method and the development method A, but no crack nor necking occurred in the development method B.

Industrial availability

Thus, according to the press forming method and the press forming apparatus of the present invention, when the vertical wall portion of a longitudinally curved part having a cross-sectional shape of a cross shape or a hat shape is formed, the material is preferentially moved from the top plate side, So that the shrinkage flange deformation can be avoided from occurring in the flange portion. When the ridgeline which is the boundary between the top plate portion and the vertical wall portion is inclined relative to the press forming direction, the material sandwiched between the metal molds during the draw forming can be rotated so as to move in the longitudinal direction of the component. The deformation of the stretch flange can be suppressed. According to the manufacturing method and the molded part of the present invention, when a longitudinally curved part having a cross-sectional shape of a cross shape or a hat shape is press-molded, the occurrence of wrinkles due to the contraction flange deformation and the elongation flange deformation It is possible to suppress one or both of the occurrence of cracks caused by the cracks.

1: die
2: punch
3:
4: Blank
5: Parts
5a: top plate
5b:
5c: flange portion
6: intermediate molded product
7: Pad
8: Plate
B: Location where flange deformation occurs
C: Slope distance
E: Extension flange deformation
S: Shrinkage flange deformation

Claims (14)

A press forming method for suppressing the occurrence of wrinkles due to shrinkage flange deformation of a component curved in the longitudinal direction having a cross-sectional shape of a cross shape or a hat shape,
The material is moved from the side of the top plate to the side of the vertical wall preferentially while the stretch flange deformation is generated in the material by restricting the movement of the material as a part of the blank from the flange portion side to the vertical wall portion,
Further, the occurrence of wrinkles of the material of the flange portion and the top plate portion is suppressed by the mold. The method according to claim 1,
In the single draw forming, the flange portion where the contraction flange deformation occurs is shared, and the two pieces are simultaneously formed so as to be symmetrical with respect to the flange portion, thereby suppressing the movement of the material from the flange portion side to the vertical wall portion . CLAIMS 1. A press forming method for suppressing occurrence of cracks due to elongation flange deformation of a component curved in the longitudinal direction having a cross-sectional shape of a cross shape or a hat shape,
The ridgeline which is the boundary between the top plate portion and the vertical wall portion is inclined relative to the press forming direction to rotate the material that is a part of the blank sandwiched between the dies during the draw forming so as to move in the longitudinal direction of the component, To thereby generate a compressive strain in the resin,
Further, the occurrence of wrinkles in the material of the flange portion and the top plate portion is suppressed by the mold. The method of claim 3,
Wherein a surface parallel to the press forming direction is formed in the mold so as to suppress rotation of the material. A press molding method characterized by using the press molding method according to claim 1 or 2 together with the press molding method according to claim 3 or 4. 6. The method according to any one of claims 3 to 5,
Characterized in that the wrinkle suppression pressure for the blank is controlled to 0.1 to 100 MPa or the gap between the mold and the material during the molding of the vertical wall portion is maintained at 0 to 200% Molding method. 7. The method according to any one of claims 1 to 6,
And a metal sheet having a tensile strength of 440 to 1470 MPa is used as a blank. A method for manufacturing a component, characterized in that a component bent in a longitudinal direction having a cross-sectional shape of a chisel or a hat shape is formed from a flat blank using the press molding method according to any one of claims 1 to 7 . 1. A press forming apparatus for suppressing the occurrence of wrinkles caused by deformation of a shrink flange of a component curved in the longitudinal direction having a cross-sectional shape of a cross-hat or a hat,
Contraction flange deformation restraining means for restricting the movement of the material as a part of the blank from the flange portion side to the vertical wall portion so as to move the material from the top plate portion to the vertical wall portion while generating stretch flange deformation in the material,
And wrinkle suppressing means for suppressing the generation of wrinkles of the material between the flange portion and the top plate portion between the materials. 10. The method of claim 9,
Wherein the shrinking flange deformation restraining means is a forming portion that shares a flange portion where shrink flange deformation occurs in a single draw forming and simultaneously forms two parts so as to be symmetrical with respect to the flange portion, Device. CLAIMS 1. A press forming apparatus for suppressing the occurrence of cracks due to deformation of an elongated flange of a component curved in the longitudinal direction having a cross-sectional shape of a cross shape or a hat shape,
A ridge line which is a boundary between the top plate portion and the vertical wall portion is tilted with respect to the press forming direction to generate a rotational force to move a material which is a part of the blank sandwiched between the dies during draw forming in the longitudinal direction of the component, The elongation flange deformation restricting means for causing compression deformation in the plate surface of the elongated flange,
And wrinkle suppressing means for suppressing the generation of wrinkles of the material between the flange portion and the top plate portion between the materials. 12. The method of claim 11,
Wherein the stretch flange deformation restraining means is a member having a surface parallel to the press forming direction, which is in sliding contact with the edge of the material and suppresses rotation of the material. A press-forming apparatus comprising the press-forming apparatus according to claim 9 or 10 and the press-forming apparatus according to claim 11 or 12. A molded part formed by press-molding from a flat blank using the press-forming apparatus according to any one of claims 9 to 13, and being a part bent in a longitudinal direction having a cross-sectional shape of a cross shape or a hat shape .

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