KR102018964B1 - Press-forming method, method of manufacturing component with such a method, and press-forming apparatus - Google Patents

Abstract

(Problem) Suppressing generation of wrinkles by shrinkage flange deformation and cracking by extension flange deformation when press forming a high strength metal plate into a component bent in the length direction of the part.
(Measures) In the press-molding method of suppressing the occurrence of wrinkles due to shrinkage flange deformation of a component curved in a longitudinal direction having a U-shaped or hat-shaped cross section, from the flange portion side of the material which is a part of the blank to the vertical wall portion. The material is moved from the top plate portion side to the vertical wall portion preferentially while suppressing the movement of the material, and the ridge line which is the boundary between the top plate portion and the vertical wall portion is inclined with respect to the press forming direction to draw molding. The material which is a part of the blank sandwiched between the molds is rotated to move in the part length direction, and the rotation is suppressed to generate compressive deformation in the plate surface in the part length direction, and further, generation of wrinkles in the material of the flange part and the top plate part is prevented. Press molding room of curved parts, characterized in that suppressed by a mold It is a law.

Description

PRESS-FORMING METHOD, METHOD OF MANUFACTURING COMPONENT WITH SUCH A METHOD, AND PRESS-FORMING APPARATUS}

TECHNICAL FIELD This invention relates to the press-molding method of the part curved in the longitudinal direction which has the shape of a cross-shaped or hat-shaped. Specifically, press molding which suppresses generation | occurrence | production of the crack by elongation flange deformation, and wrinkles by shrinkage flange deformation. It is about a method. Moreover, this invention also relates to the manufacturing method of the component using the press molding method. Moreover, this invention relates to the press-molding apparatus of the component curved in the longitudinal direction which has a cross-shaped or a hat-shaped cross section, Especially, it suppresses generation | occurrence | production of the crack by elongation flange deformation, and the wrinkle by shrinkage flange deformation. It relates to a press molding apparatus.

In recent years, in order to make both the collision safety of an automobile and the weight reduction of a vehicle body, the metal plate of higher strength is calculated | required. However, the metal plate tends to decrease the ductility largely related to press formability as the tensile strength is improved. For this reason, foam (bending) molding and draw (drawing) molding tend to be more versatile than elongation molding in which the ductility of the material greatly affects the moldability.

In draw molding, the wrinkle suppression part is arrange | positioned at the position which becomes a flange part of the blank which is a metal plate used as the material of a part to shape | mold, a blank is mounted on a punch and a wrinkle suppression part, and a die is placed above a blank. Install. Next, by lowering the die, the blank is pressed to the die and the wrinkle suppressing portion, and the blank is bent while loading the tension to the blank. At this time, the material (part of the blank) largely drawn between the punch and the die by being pressed by the die and the wrinkle suppressing portion forms the vertical wall portion of the part. Therefore, even if the material lacks ductility, molding of the vertical wall portion becomes easy. In addition, since the out-of-plane deformation (wrinkling) of the blank is constrained by the die and the wrinkle suppressing portion, and the tension applied to the material drawn into the vertical wall portion is easily adjusted, there is an advantage that it is easy to form a complicated part shape.

On the other hand, when manufacturing a complicated part shape by draw molding, there exists a problem that a crack and a wrinkle easily generate | occur | produce in the edge part of the blank of a position used as a flange part, especially in the part curved in the longitudinal direction of a part. It is easy to be a problem. The front view, side view, and sectional view along the AA line of (a) of FIG. 1 are shown in (a), (b) and (c) of the blank shape used when shape | molding the component curved in the longitudinal direction by the conventional method. 2 (a), 2 (b) and 2 (c), examples of shrinkage flange deformation (S) and extension flange deformation (E) generated when molding a component curved in the longitudinal direction by a conventional method are shown. 3, (a), (b) shows sectional drawing before shaping | molding of the metal mold | die structure in the AA cross section of FIG. In the drawings, reference numeral 1 denotes a die, 2 punches, 3 wrinkle suppression portion, 4 blanks, and 5 denotes a molded part.

The part 5 has the top plate part 5a, the vertical wall part 5b, and the flange part 5c, and when the longitudinal wall part 5b, the flange part 5c, etc. are curved, the die 1 and When the material that is a part of the blank 4 moves between the wrinkle suppressing portions 3, the deformation (extension flange deformation) that is elongated in the circumferential direction of the curved shape due to the lack of line length, or the deformation that is conversely compressed (shrink flange deformation) ) In the vicinity of the end of the blank 4, a crack occurs when an elongated flange deformation exceeds the ductility of the material, and when a shrinkage flange deformation exceeds the buckling strength of the material, wrinkles occur. It is easy to be a problem.

As a method of suppressing wrinkles due to shrinkage flange deformation, a method of dispersing shrinkage flange deformation as in Patent Document 1 is known. Moreover, as a method of suppressing the crack by extension flange deformation, the method of disperse | distributing extension flange deformation like the patent document 2 is known.

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

However, the higher the strength of the metal plate, the higher the stress generated with respect to the deformation amount, so that a stress exceeding the buckling strength of the metal plate tends to occur, resulting in larger wrinkles. Moreover, since the intensity | strength of a wrinkle increases with the high strength metal plate, sufficient measures cannot be taken by the method of dispersing wrinkles like patent document 1. And since the ductility of a blank edge part falls that the high strength metal plate becomes, there exists a limit to the crack which can be prevented by dispersion | distribution of extension flange deformation like patent document 2. As shown in FIG.

As described above, in the case of press-molding a high-strength metal plate into a component curved in the longitudinal direction of the part, in order to suppress wrinkles and cracks caused by shrinkage flange deformation or extension flange deformation, the occurrence of shrinkage flange deformation and extension flange deformation itself is prevented. Alleviate.

The press-molding method of the present invention, which advantageously solves the above problems, is a method of suppressing the occurrence of wrinkles due to shrinkage flange deformation of a component curved in a longitudinal direction having a U-shaped or hat-shaped cross-sectional shape, which is part of a blank. By suppressing the movement from the flange portion side to the vertical wall portion, the material is preferentially moved from the top plate portion to the vertical wall portion while generating an elongated flange deformation in the material, and also the occurrence of wrinkles in the material of the flange portion and the top plate portion. It is characterized by suppressing the to a mold.

Moreover, the press-molding method of this invention which advantageously solves the said subject is a method of suppressing generation | occurrence | production of the crack by deformation of the extension flange of the component curved in the longitudinal direction which has a cross-sectional shape of a U-shape or a hat shape, A top plate By inclining the ridge line, which is the boundary between the part and the vertical wall part with respect to the press forming direction, the material which is a part of the blank sandwiched between the molds during the draw molding is rotated to move in the part length direction, and the rotation is suppressed so as to suppress the rotation. Compression deformation is generated, and generation of wrinkles in the material of the flange portion and the top plate portion is suppressed by the mold.

And the manufacturing method of the component of this invention uses the press molding method of this invention mentioned above, and forms the component curved in the longitudinal direction which has a U-shaped or hat-shaped cross-sectional shape from the flat blank. will be.

On the other hand, the press-molding apparatus of the present invention advantageously solves the above problems in the press-molding apparatus for suppressing the occurrence of wrinkles due to shrinkage flange deformation of the component curved in the longitudinal direction having a cross-sectional shape of the U-shape or hat-shaped Shrink flange deformation suppression means for moving the material preferentially from the top plate portion side to the vertical wall portion while generating an extension flange deformation in the material by suppressing movement of the material that is part of the blank from the flange portion side to the vertical wall portion; And wrinkle suppression means for suppressing the occurrence of wrinkles of the material with the material between the top plate portion interposed therebetween.

Moreover, the press molding apparatus of another invention which advantageously solves the said subject is a press molding apparatus which suppresses generation | occurrence | production of the crack by deformation of the extension flange of the component curved in the longitudinal direction which has a cross-sectional shape of a U-shape or a hat shape. By inclining a ridge line that forms the boundary between the top plate and the vertical wall with respect to the press forming direction, a rotational force for moving the material, which is a part of the blank sandwiched between the molds in the longitudinal direction of the part during the draw forming, is suppressed, thereby suppressing the rotational force. And an extension flange deformation suppression means for generating compressive deformation in the plate surface in the longitudinal direction, and wrinkle suppression means for suppressing generation of wrinkles of the material between the flange portion and the top plate portion.

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According to the press-molding method and the press-molding apparatus of the present invention, when forming a vertical wall portion of a component curved in the longitudinal direction having a U-shaped or hat-shaped cross-sectional shape, the conventional material for moving the material from the flange portion side to the vertical wall portion Unlike draw molding, since the vertical wall portion is formed by preferentially moving the material from the top plate portion side, the occurrence of shrinkage flange deformation in the flange portion can be avoided. In addition, if the ridgeline that forms the boundary between the top plate portion and the vertical wall portion is inclined with respect to the press forming direction, the material sandwiched between the molds during the draw forming can be rotated to move in the component longitudinal direction. Therefore, the plate surface is suppressed by suppressing the rotation. Compression deformation can be applied to the inside to suppress elongation flange deformation. Moreover, by using together the suppression method of the shrinkage flange deformation and the suppression method of the extension flange deformation, it is possible to simultaneously suppress the occurrence of creases and cracks in the flange portion of the component curved in the longitudinal direction. And according to the manufacturing method of the component of this invention using the press molding method of this invention, and the molded part press-molded using the press molding apparatus of this invention, it curves in the longitudinal direction which has a cross-sectional shape of a U-shape or a hat shape. When press-molding the molded part, it is possible to suppress one or both of occurrence of wrinkles due to shrinkage flange deformation and generation of cracks due to extension flange deformation.

In addition, in the press molding method and the press molding apparatus of the present invention, in a single draw molding, two parts are simultaneously formed so as to share a flange portion where shrinkage flange deformation occurs and become symmetrical with respect to the flange portion, It is preferable to suppress the movement of material from the flange portion side to the vertical wall portion. By doing in this way, generation | occurrence | production of the wrinkle by the shrinkage flange deformation can be suppressed with a simple structure.

Moreover, in the press molding method and press molding apparatus of this invention, it is preferable to form the surface parallel to the press molding direction in the member of a metal mold | die, and to suppress rotation of a material. By doing in this way, generation | occurrence | production of the crack by extension flange deformation can be suppressed with a simple structure.

Moreover, in the press molding method and press molding apparatus of this invention, it is preferable to use the two press molding methods or two press molding apparatus mentioned above together. By doing in this way, generation | occurrence | production of the wrinkle and crack generation of the flange part of the component curved in the longitudinal direction can be suppressed simultaneously.

In addition, in the press molding method and the press molding apparatus of the present invention, the wrinkle suppression pressure with respect to the blank is set to 0.1 to 100 MPa or the gap between the mold and the material during the molding of the vertical wall portion is used to suppress the wrinkles caused by the mold. It is preferable to set it as 0 to 200% of the plate | board thickness of the.

Moreover, in the press molding method and press molding apparatus of this invention, it is preferable to use the metal plate whose tensile strength is 440-1470 Mpa as a blank. In this case, one or both of generation of wrinkles due to shrinkage flange deformation and crack generation due to extension flange deformation can be suppressed during press molding of a component made of a high strength metal plate.

(A), (b), and (c) of FIG. 1 are a front view, a side view, and an AA line of FIG. 1 (a) of a blank shape used when molding a component curved in the longitudinal direction by a conventional method. It is a cross section.
(A), (b) and (c) are the front view, the side view, and the front view which show the example of the contraction flange deformation and expansion flange deformation which arise when shape | molding the component curved in the longitudinal direction by the conventional method. It is sectional drawing along the AA line of (a).
(A), (b) is sectional drawing before shaping | molding and the completion of shaping | molding which show the metal mold | die structure in AA cross section of FIG.
(A), (b) and (c) are the front view, side view, and figure which show the shape of the blank used when shape | molding the component curved in the longitudinal direction in one Embodiment of the press molding method of this invention. It is sectional drawing along the AA line of 4 (a).
(A), (b) and (c) are the front view, side view, and sectional drawing along the AA line of FIG. 4A (a) which show the shape of the intermediate molded article shape | molded by the press molding method of the said embodiment. .
(A), (b) and (c) are the front view, side view, and sectional drawing along the AA line of FIG. 4B (a) which show the shape of the component shape | molded by the press molding method of the said embodiment.
(A), (b) is sectional drawing before shaping | molding and the completion of shaping | molding which show the metal mold | die structure in AA cross section of FIG. 4A (a).
(A), (b) is sectional drawing before shaping | molding and the completion of shaping | molding which show the metal mold | die structure in AA cross section of FIG. 4b (a).
(A), (b) and (c) are the front view, side view, and sectional drawing along the AA line of FIG. 6 (a) which show the shape of the blank which this inventor used for the investigation of the material behavior at the time of draw molding. to be.
(A), (b) and (c) are the front view, side view, and sectional drawing along the AA line of FIG. 6A of FIG. 6A which show the shape of the intermediate | middle molded article press-molded by the said material behavior investigation.
(A), (b) and (c) of FIG. 6B are a front view, a side view, and sectional drawing along the AA line of FIG. 6B (a) which show the shape of the component press-molded by the said material behavior investigation.
(A), (b) and (c) are the front view, side view which show the shape of the blank used when shape | molding the component curved in the longitudinal direction in another embodiment of the press molding method of this invention. It is sectional drawing along the AA line of FIG.
(A), (b) and (c) are the front view, side view, and sectional drawing along the AA line of FIG. 7A (a) which show the shape of the intermediate molded article shape | molded by the press molding method of the said embodiment. .
(A), (b) and (c) are the front view, side view, and sectional drawing along the AA line of FIG. 7B (a) which show the shape of the component shape | molded by the press molding method of the said embodiment.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described in detail by the Example based on drawing. 4 (a), 4 (b) and 4 (c) are views of blanks used when molding a component curved in the longitudinal direction in one embodiment of the press-molding method of the present invention. It is a front view, a side view, and sectional drawing along the AA line of FIG. 4 (a) showing a shape, FIG. 4A (a), FIG. 4A (b), and FIG. 4A (c) are press molding of the said embodiment. It is a front view, a side view, and sectional drawing along the AA line of FIG. 4A (a), and FIG. 4B (a), FIG. 4B (b), and FIG. 4B (c) which show the shape of the intermediate molded article shape | molded by the method. The front view, the side view, and the cross-sectional view along the AA line of FIG. 4B (a) which show the shape of the component shape | molded by the press molding method of the said embodiment. 5A and 5A are cross-sectional views before molding and when molding is completed, showing the mold structure in the AA cross section of FIG. 4A, and FIGS. 5B and 5A. 5b (b) is sectional drawing before shaping | molding and the completion of shaping | molding which show the metal mold | die structure in AA cross section of FIG. 4B (a). In addition, the part same as a prior art example in a figure is shown with the same code | symbol as it.

MEANS TO SOLVE THE PROBLEM First, the present inventors repeated various studies about the countermeasure method of wrinkles by deformation of a shrinkage flange. At that time, since the shrinkage flange deformation occurred when the material length was moved from the flange portion side to the vertical wall portion, it was considered whether the same vertical wall portion could not be formed by the expansion flange deformation lacking the line length. Then, what was necessary was just to reverse the moving direction of the material for shaping a vertical wall part. In other words, when the vertical wall portion is molded from the top plate portion side rather than from the flange portion side, wrinkles do not occur in the flange portion. In addition, since the position where the extension flange deformation occurs is the side of the top plate portion away from the end of the blank, there is an advantage that the crack caused by the extension flange deformation is hardly generated.

4, 4A and 4B show a countermeasure of shrinkage flange deformation based on the embodiment of the present invention, and show the structure of the mold as the press-molding apparatus in the cross section along the AA line therein. It shows in 5b. The press molding direction is the paper vertical direction with respect to the front view. In order to restrain material movement at the position B where shrinkage flange deformation occurs in the conventional construction method, as shown in FIGS. 4A to 4B, the flange portion where the shrinkage flange deformation occurs is shared, and the flange portion is referred to. What is necessary is just to shape | mold two parts 5 simultaneously so that it may become symmetrical. As a result, as shown in FIG. 4A, material movement from the top plate portion side can be preferentially generated, and the extension flange deformation (E) is generated by extending the line length of the material. And in the next process, as shown to FIG. 4B, when the outer flange part is shape | molded, two components curved in the longitudinal direction by which shrinkage | contraction flange deformation was suppressed are completed. That is, this structure which takes two of these parts of a metal mold | membrane is corresponded to shrinkage flange deformation suppression means.

In the process of FIG. 4B, when the vertical wall portion or the top plate portion is bent in the component length direction, the material moves unevenly to the vertical wall portion, so that the material moving the top plate portion is moved to the mold in order to suppress unnecessary out-of-plane deformation (wrinkling). It is desirable to suppress. Moreover, since a flange part becomes a junction part with another component, it is preferable to prevent out-of-plane deformation with a metal mold | die. Specifically, the top plate portion may be restrained by being sandwiched between the punch 2 and the pad 7, and the flange portion side may be placed between the die 1 and the wrinkle suppressing portion 3 to the extent that the material can be moved. In addition, in the process of FIG. 4B, when the material moves from the top plate side to the vertical wall portion during the draw molding, shrinkage flange deformation occurs, which may cause wrinkles. Therefore, the material of the top plate portion is restrained by being placed between the punch 2 and the pad 7 as described above, and the flange side may be placed between the die 1 and the wrinkle suppressing portion 3 to such an extent that the material can be moved. That is, the structure which sandwiches these materials of a metal mold | die is corresponded to a wrinkle suppression means.

In addition, in the press-molding method of the present invention, the method of restraining material movement at the position B where shrinkage flange deformation occurs by the conventional construction method is not limited to the example of FIG. 4B, and friction by placing a metal plate between molds. In addition to the resistance, it is also possible to use the deformation resistance of the metal plate by placing the metal plate between the metal molds having the uneven shape such as beads or embosses.

Next, this inventor repeated various studies about the countermeasure method of the crack by extension flange deformation. At that time, it was found that the characteristic change as shown in Fig. 6 was seen in the behavior of the material during draw molding by applying the curvature in the component longitudinal direction to the component formed in the direction in which the height of the component changed.

6 (a), 6 (b) and 6 (c) are a front view, a side view and a view (a) of FIG. 6 showing the shape of the blank used by the present inventors to investigate the material behavior during draw molding. 6A, 6A, 6A, and 6A are front views, side views, and FIG. 6A showing the shapes of the intermediate molded articles press-molded by the material behavior investigation. 6A, 6B, 6B, and 6C are cross-sectional views along the AA line of FIG. And FIG. 6B is a cross-sectional view along the line AA of (a).

As a result of examining the results of the above-described material behavior investigation, the ridgeline that forms the boundary between the top plate portion and the vertical wall portion is shown in Fig. 6A (b) with respect to the press molding direction (the paper vertical direction in the front view and the paper horizontal direction in the side view). It was discovered that by inclining as shown by the inclination distance C in the middle, the material of a part of the blank 4 can be rotated so that it may move to a component longitudinal direction (thick arrow direction of FIG. 6A, FIG. 6B) during draw molding. The amount of rotation changes by the inclination angle with respect to the press molding 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 from the top plate portion side as shown in Fig. 6A (the first step) to the movement from the flange portion side as shown in Fig. 6B (the second step), the rotating direction is reversed.

7 (a), 7 (b) and 7 (c) show the shape of the blank used when molding a component curved in the longitudinal direction in another embodiment of the press-molding method of the present invention. The front view shown, the side view, and sectional drawing along the AA line of FIG. 7A, FIG. 7A (a), FIG. 7A (b), and FIG. 7A (c) are shape | molded by the press molding method of the said embodiment. The front view, the side view, and the sectional view along the AA line of FIG. 7A (a), FIG. 7B (a), FIG. 7B (b), and FIG. 7B (c) which show the shape of one intermediate | mold molded article are said embodiment It is a front view, a side view, and sectional drawing along the AA line of FIG. 7B (a) which shows the shape of the component shape | molded by the press molding method of FIG.

This inventor came up with the press molding method of embodiment of this invention which can suppress both a shrinkage flange deformation and an extension flange deformation shown to FIG. 7-7B using the said knowledge. If the rotation occurs, even if the rotational force is suppressed, compressive deformation can be caused in the plate surface where the elongated flange deformation occurs, and in this embodiment, the metal plate 8 is pressed into the blank 4 of the press-molding die. B) The intermediate molded article 6 is provided at a position to abut on both end faces in the longitudinal direction of the component. This plate 8 of the metal mold corresponds to the extension flange deformation suppressing means.

The method of hindering the rotation of the material is not only a method of providing the metal plate 8 as shown in Figs. 7A and 7B, but also a contact face parallel to the press molding direction needs to be formed in the mold. Excellent in cost Since the contact surface slides in contact with the end face of the blank 4 or the intermediate molded product 6 during draw molding, it is prevented from being cut by using a material that is harder than the material of the blank 4. It is preferable to set it as the structure which can replace surfaces.

According to the press-molding method and the press-molding apparatus of the present invention, not only a component curved in the longitudinal direction having a hat-shaped cross-sectional shape, but also all materials located in the flange portion are used for molding the vertical wall, so that Parts can also be manufactured.

It is preferable to make a wrinkle suppression pressure into 0.1-100 Mpa for suppression of the wrinkles by a metal mold | die. If the pressure is less than 0.1 MPa, it is difficult to suppress out-of-plane deformation (wrinkling) of the blank 4, and a pressure exceeding 100 MPa is not preferable in view of cost because a high rigid pressurization device is required. When the wrinkle suppression pressure is not used, it is preferable to keep the gap between the metal plate of the mold and the blank 4 or the intermediate molded article 6 at 0 to 200% of the plate thickness during molding of the vertical wall portion. There is no particular advantage in making the gap less than 0% of the sheet 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, when the gap is larger than 200%, the wrinkles generated become large, so that it is difficult to remove the wrinkles in the subsequent trim step.

It is preferable that the metal plate used as the raw material of the blank 4 is 440-1470 Mpa of tensile strength. Since the metal plate whose tensile strength is less than 440 Mpa is excellent in ductility and drawing moldability, there is little advantage in using the method of this invention. Moreover, since the metal plate exceeding 1470 Mpa lacks ductility, the crack in the punch shoulder part and die shoulder part which are not made into object in this invention tends to generate | occur | produce, and it may become impossible to shape a part.

Using a 270, 440, 980, 1180, 1470 MPa grade steel sheet shown in Table 1 as a test material, the conventional method evaluates the molding result by the draw molding shown in FIG. 2, and the invention method is 2 shown in FIGS. The molding result was evaluated by the development method A of shaping | molding of a process, and the development method B of shaping | molding of two processes shown in FIGS. 7-7B. The metal plate was pressed at 10 MPa by a mold. The evaluation results are shown in Table 2. Evaluation of the molded article was performed visually, and the wrinkles and cracks which occurred in the flange part were evaluated in three steps of (circle), (triangle | delta), and *. The case where remarkable wrinkles and a crack generate | occur | produced x and the case where a slight wrinkles and a necking generate | occur | produced (triangle | delta) and the case where a wrinkle, a crack, or a necking do not generate | occur | produced was made into (circle).

In the 270 MPa-grade steel sheet, neither the conventional method nor the development methods A and B can be molded without wrinkles or cracks. In the case of the 440 MPa grade steel sheet, significant wrinkles occurred in the conventional method, but the development of wrinkles was prevented in the development methods A and B. In terms of crack evaluation, necking was observed in the conventional method and development method A, but neither crack nor necking occurred in development method B. In the case of 980, 1180 and 1470 MPa grade steel sheets, the wrinkles observed in the conventional method were not observed in the development methods A and B. In the crack evaluation, cracking occurred in the conventional method and development method A, but neither crack nor necking occurred in the development method B.

Industrial availability

In this way, according to the press-molding method and the press-molding apparatus of the present invention, when forming a vertical wall portion of a component curved in a longitudinal direction having a U-shaped or hat-shaped cross-sectional shape, the vertical wall portion is preferentially moved by moving the material from the top plate portion side. Because of the molding, the occurrence of shrinkage flange deformation in the flange portion can be avoided. In addition, if the ridgeline that forms the boundary between the top plate portion and the vertical wall portion is inclined with respect to the press forming direction, the material sandwiched between the molds during the draw forming can be rotated to move in the component longitudinal direction. Therefore, the plate surface is suppressed by suppressing the rotation. Compression deformation can be applied to suppress the extension flange deformation. And according to the manufacturing method and the molded part of the component of this invention, when press-molding the part curved in the longitudinal direction which has a cross-shaped shape of a U-shape or a hat, it is effective in the generation | occurrence | production of a wrinkle by a shrinkage flange deformation, and an extension flange deformation. One or both of generation | occurrence | production of the crack by this can be suppressed.

1: die
2: punch
3: wrinkle suppression
4 blank
5: parts
5a: top plate
5b: vertical wall
5c: Flange
6: intermediate moldings
7: pad
8: plate
B: position where shrink flange deformation occurs
C: slope distance
E: extension flange deformation
S: Shrink Flange Deformation

Claims (14)

In the press-molding method for suppressing the occurrence of wrinkles due to shrinkage flange deformation of the component curved in the longitudinal direction having a U-shaped or hat-shaped cross-sectional shape,
By suppressing the movement of the material that is part of the blank from the flange portion side to the vertical wall portion, the material is preferentially moved from the top plate portion to the vertical wall portion while generating an extension flange deformation in the material,
Further, the press-molding method characterized by suppressing the occurrence of wrinkles in the material of the flange portion and the top plate portion with a mold. The method of claim 1,
In the independent draw molding, the flange portion where shrinkage flange deformation occurs is shared, and two parts are simultaneously molded so as to be symmetrical with respect to the flange portion, thereby suppressing the movement of material from the flange portion side to the vertical wall portion. Press molding method, characterized in that. In the press-molding method for suppressing the occurrence of cracking caused by the deformation of the elongated flange of the component curved in the longitudinal direction having a U-shaped or hat-shaped cross-sectional shape,
By inclining the ridge line that borders the top plate and the vertical wall with respect to the press forming direction, the material, which is part of the blank sandwiched between the molds during the draw forming, is rotated to move in the length direction of the part, and the rotation is suppressed so that the plate surface in the part length direction is suppressed. Generate compressive strain within the
Moreover, the press molding method characterized by suppressing generation | occurrence | production of the wrinkle of the material of a flange part and a top plate part by a metal mold | die. The method of claim 3, wherein
The press molding method characterized by forming the surface parallel to a press molding direction in a metal mold | die, and suppressing rotation of a material. The press molding method of Claim 1 and the press molding method of Claim 3 are used together. The press molding method characterized by the above-mentioned. The method according to claim 3 or 4,
The press characterized in that the wrinkle suppression pressure on the blank is 0.1 to 100 MPa for suppressing wrinkles by the mold, or the gap between the mold and the material during molding of the vertical wall portion is maintained at 0 to 200% of the sheet thickness of the material. Molding method. The method according to any one of claims 1 to 4,
A metal sheet having a tensile strength of 440 to 1470 MPa is used as a blank. A method for producing a component comprising the press-molding method according to any one of claims 1 to 4, to form a curved part in a longitudinal direction having a cross-sectional shape of a U-shape or a hat shape from a flat blank. . In the press-molding apparatus for suppressing the occurrence of wrinkles due to shrinkage flange deformation of the component curved in the longitudinal direction having a U-shaped or hat-shaped cross-section,
Contraction flange deformation suppressing means for moving the material from the top plate portion preferentially to the vertical wall portion while generating an extension flange deformation in the material by suppressing the movement from the flange portion side of the material that is part of the blank to the vertical wall portion;
And a wrinkle suppressing means for suppressing the occurrence of wrinkles of the material with the material between the flange portion and the top plate portion interposed therebetween. The method of claim 9,
The shrinkage flange strain suppressing means is a press portion for simultaneously molding two parts so as to share the flange portion where shrinkage flange deformation occurs in single draw molding and to be symmetrical with respect to the flange portion. Device. In the press-molding apparatus for suppressing the occurrence of cracks caused by the deformation of the elongated flange of the component curved in the longitudinal direction having a U-shaped or hat-shaped cross-sectional shape,
By inclining the ridge line that borders the top plate and the vertical wall with respect to the press forming direction, it generates a rotational force for moving the material, which is a part of the blank sandwiched between the molds, in the component longitudinal direction during draw forming, and suppresses the rotational force in the component longitudinal direction. Expansion flange deformation suppression means for generating a compression deformation in the plate surface of the
And a wrinkle suppressing means for suppressing the occurrence of wrinkles of the material with the material between the flange portion and the top plate portion interposed therebetween. The method of claim 11,
And said elongated flange deformation inhibiting means is a member having a surface parallel to the press forming direction for sliding contact with a component longitudinal direction end face of said material to suppress rotation of said material. The press-molding apparatus of Claim 9 and the press-molding apparatus of Claim 11 are both provided, The press-molding apparatus characterized by the above-mentioned. delete

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