JPH05228542A - Press forming method - Google Patents

Abstract

PURPOSE:To provide the press forming method by which a press formed part having a rugged part or an opening part on the forming surface can be obtained easily and rationally. CONSTITUTION:At the time of forming a press formed part having a rugged part on the forming surface, a rugged part 17 is formed in advance on the forming scheduled surface of a plate-like stock 10, and subsequently, a die 22 is pressed from the recessed part surface side of the stock on which the rugged part is formed, and also, forming is executed by providing a space part 33 on the stock surface having a projecting part, of the opposite side to the pressing side.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a press-molding method, and more particularly to a press-molding method for a press-molded article having an uneven portion or an opening on a molding surface.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 9, a press-formed product having a concavo-convex portion on its forming surface is first formed into a predetermined shape by pressing a plate-like material 48 such as a metal plate with a pressing die and a receiving die. The molding surface 50 is formed, and then the uneven portion 52 is formed on the molding surface 50 by embossing using an embossing punch.

Further, in forming a press-formed product having an opening on the forming surface, a plate-shaped material similar to the above is pressed by a pressing die and a receiving die to form a forming surface of a predetermined shape, and then formed by a punch punch. The opening was formed on the surface.

[0004]

However, it is not easy to work and the workability is inferior, and the tool is likely to be damaged when the unevenness or the opening is formed on the molding surface which is not already flat by press molding. There was also such a problem.

On the other hand, when an uneven portion or an opening is formed on the planned molding surface in advance and then a molding surface having a predetermined shape is press-molded by sandwiching the molding surface with a pressing die and a receiving die, the concave and convex portions are crushed. Or, there arises a problem that the inner peripheral edge of the opening is crushed and the hole becomes smaller. Therefore, the present invention provides a press molding method that solves the above problems.

[0006]

In order to solve the above-mentioned problems, the first aspect of the present invention is to form a concavo-convex portion on a molding surface of a plate-shaped material in advance when molding a press-formed product having a concavo-convex portion on the molding surface. Then, the pressing die is pressed from the concave surface side of the material on which the concave and convex portions are formed, and the material surface having the convex portion on the opposite side to the pressing side is provided with a space portion for molding. .

The second aspect of the present invention is to form a press-formed product having an opening on the forming surface by forming an opening on the surface of the plate material to be formed in advance, and then from one surface of the material on which the opening is formed. While pressing the pressing die, the material surface having the opening on the side opposite to the pressing side is provided with a space portion for molding.

[0008]

In the first aspect of the invention, as shown in FIG. 8, first, the uneven portion 58 is formed on the planned surface 56 of the plate-shaped material 54, and then the molded surface 56 is pressed from the concave surface 60 side by the pressing die. To form a molding surface having a predetermined shape. At that time, since the concavo-convex portion 58 can be formed on the flat plate-shaped material 54 which has not yet been molded, the work for forming the concavo-convex portion 58 becomes extremely easy. Moreover, at the time of pressing by the pressing die, since a space is provided on the side of the convex portion 62 opposite to the pressing side, the convex portion is not crushed.

On the other hand, according to the second aspect of the invention, when the pressing die is pressed after the opening is formed, the inner peripheral edge of the opening is pressed from both sides because the space is provided on the material surface opposite to the pressing surface. Will not be crushed. Therefore, the hole diameter of the opening does not become small.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the accompanying drawings. 1 to 5 are sectional views showing a molding process in an embodiment of the present invention. This example is an example of press-molding a molded product having an uneven portion on the molding surface.

FIG. 1 shows a step of forming an uneven portion. First, a plate-shaped material 10 made of a metal plate or the like is placed on a table 12, and a molding surface 14 of the plate-shaped material is embossed by the embossing punch 1
6 is pressed to form an uneven portion (emboss). FIG. 6 is a plan view of the plate-shaped material 10 thus obtained. In the figure, reference numeral 17 is an uneven portion, 18 is a central hole forming tool, and 19 is a central hole.

2 and 3 show a step of pressing the molding surface with a pressing die. The plate-shaped material 10 after the uneven portion is formed,
It is arranged on the pressing die 22 so that the concave surface 20 side is the pressing die 22 side. Then, the planned surface of the plate-shaped material 10 is pressed by the pressing die 22 from the concave surface 20 side to form a molding surface 24 having the surface shape of the pressing die. At this time, the outer peripheral edge of the plate-shaped material 10 is sandwiched by the upper and lower holding portions 26 and 28, and the surface of the plate-shaped material 10 on the side opposite to the pressing die 22 is pressed only by the central holding portion 30 by the central holding portion 30. A space 33 is formed between the upper surface of the press 32 and the other parts of the press upper frame 32 without being pressed by the surface.

FIG. 4 shows a trimming process of the plate-shaped material. After forming the molding surface, the plate-shaped material 1 is trimmed by the trim dies 34 and 36.
0 Trim by cutting the excess part of the outer peripheral edge. 38
Is a stripper.

FIG. 5 shows the outer peripheral drawing step. The outer peripheral edge 10a of the plate-shaped material 10 after trimming is pressed and deformed by the die 40 for outer peripheral drawing to the concave side of the forming surface to perform outer peripheral drawing, to obtain a final press-formed product. Numerals 42 and 44 are strippers for taking out molded products. FIG. 7 is a perspective view of the press-formed product 46 thus obtained.

The trimming step and the outer peripheral drawing step may be unnecessary depending on the shape required for the molded product. Further, in the above description, the case where the molding surface has an uneven portion is shown, but press molding of a molded product having an opening instead of the uneven portion is also performed in the same manner as described above. However, in that case, the opening forming step is first performed in place of the uneven portion forming step.

[0016]

Since the present invention has the above-mentioned structure,
It is possible to easily form irregularities or openings on the molding surface, and to prevent damage to the tool. In addition, there is no problem such as crushing of the uneven portion of the molding surface or reduction of the hole diameter of the opening, which is extremely useful in industry.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an uneven portion forming step in an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a molding surface forming step in the example.

FIG. 3 is a cross-sectional view showing a molded surface after molding in the example.

FIG. 4 is a sectional view showing a trim step in the example.

FIG. 5 is a sectional view showing an outer peripheral drawing step in the example.

FIG. 6 is a plan view of the plate-shaped material after forming the concavo-convex portion in the example.

FIG. 7 is a perspective view of a press-formed product obtained in the same example.

FIG. 8 is a cross-sectional view showing the outline of the molding process of the present invention.

FIG. 9 is a cross-sectional view showing a process outline of a conventional press molding method.

[Explanation of symbols]

 10 Plate-like Material 14 Planned Surface 17 Concavo-convex Part 20 Recessed Surface 22 Push Mold 24 Molding Surface 33 Space Part

Claims (2)

[Claims] 1. When molding a press-molded article having a concave-convex portion on the molding surface, the concave-convex portion is formed in advance on the surface to be molded of the plate-shaped material, and then,
A press-molding method, characterized in that a pressing die is pressed from the concave surface side of the material having the concave-convex portion formed, and a space is formed in the material surface having the convex portion on the opposite side to the pressing side. 2. When forming a press-formed product having an opening on the forming surface, the opening is formed in advance on the surface of the plate material to be formed, and then,
A press-molding method, characterized in that a pressing die is pressed from one surface of a material having the opening, and a space is provided on the surface having the opening opposite to the pressing side for molding.