JPS60223624A - Press forming method and press die used therefor - Google Patents

Abstract

PURPOSE:To form a recess and a projecting pattern to the base of the recess in a conspicuous state by pressing a metallic plate by an upper die consisting of a punch having a die hole and a movable die and a lower die consisting of a die mating with said dies, a movable die as well as a punch. CONSTITUTION:The metallic plate (a) to be worked is set between the upper die 1 provided with the die hole 12 on the bottom surface and the punch 11 having the movable die 13 slidable vertically in said hole and the lower die 2 provided with the die 21 mating with the punch 11 of the upper die and the movable die 22 slidable vertically on the inside periphery thereof. The die 1 is lowered to press the plate (a) by the punch 11 thereof; at the same time, the movable die 22 of the lower die descends and the plate (a) is sheared between the punch 11 of the upper die and the movable die 22 of the lower die, by which the recess a1 having a sharp angle is formed. The punch 23 of the lower die projects at the same time from the die 22 to force part of the recess a1 of the plate (a) upward from below, then the movable die 13 of the upper die ascends and the plate is subjected to shearing between the die hole 12 and the punch 23, by which the projecting pattern a2 having a sharp angle is formed on the base of the recess a1.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a press molding method for pressing a metal plate material to form a concave portion and a convex pattern protruding from the bottom surface of the concave portion in the same material, and a press mold used therein.

When forming a recess and six patterns protruding from the bottom surface of the recess in a metal plate material by a conventional press molding method, a press mold consisting of a pair of punches and a die is used. The punch and die are molded so that they fit into each other with a gap slightly larger than the thickness of the material.

By the way, in a product obtained by press-molding the above-mentioned material, there is a desire to make the concave portions and the convex patterns on the bottom of the concave portions stand out. In order to satisfy this demand, it is necessary to sharpen the corners of the boundary between the peripheral wall of the recess, the bottom wall, and the plate surface of the material, and the corner of the boundary between the four-part bottom wall and the raised wall of the convex pattern.

However, in the above-mentioned molding method using a press die, there is a gap between the punch and die that allows the material to escape, and because it is a so-called bending and drawing process, it is necessary to forcefully press the material against the punch and die while holding it down. It was not possible to sharpen the corners due to sag in the corners.

The present invention molds the metal plate material using shearing,
In addition, the technical problem is to press the material strongly against the punch and die without letting it escape during molding, and to sharpen the corners of the convex pattern on the recess and the bottom surface of the recess formed in the metal plate material. The present invention provides a press molding method that can make the convex pattern stand out, and a press mold used therein.

The press molding method of the present invention which achieves the above-mentioned technical problem involves pressing a metal plate material between an upper die and a lower die, and pressing the material from below with a movable die that fits into the inner periphery of the die of the lower die. While elastically pressing the material, shear is applied to the material by the upper die punch and the die to form a recess, and at the same time, a movable die that fits into the die hole provided in the upper die punch is used to form an area in the material that will become the bottom wall of the recess. While elastically pressing a part of the mold from above, shearing is applied to a part of the area using a punch that passes through the movable mold of the lower mold and the die hole, thereby forming a convex pattern protruding from the bottom surface of the recess. It is.

The press mold of the present invention that achieves the same problem is composed of an upper mold and a lower mold, and the upper mold has a punch, a die hole recessed from the lower surface of the punch, and a die hole that fits into the die hole so as to be vertically slidable. The lower die is provided with a die that matches the punch of the upper die, and a movable die that fits into the inner circumference of the die so as to be able to slide vertically and is elastically urged upward. The punch is provided with a movable die that is movable, and a punch that penetrates the movable die so as to be retractable from the upper surface of the movable die and fits into a die hole of the upper die.

According to the configuration of the present invention, the metal plate material is sandwiched between the upper die and the lower die and pressed, so that the movable die of the lower die elastically presses the material from below and presses the metal plate material between the upper die and the lower die. The material descends while being strongly pressed against the lower die and the upper punch, and the material is sheared between the die and punch without escaping, forming a recess with a sharp corner in the material. As the movable mold descends, the punch of the lower mold protrudes from the upper surface of the movable mold, and the movable mold of the upper mold elastically presses a part of the area that will become the bottom wall of the recess from above, thereby forming the die hole of the same mold. It rises while being strongly pressed against the punch of the lower mold, and a part of the area is sheared without escaping between the punch of the lower mold and the die hole of the upper mold, and a convex pattern with sharp corners is formed on the bottom of the recess. The concave portion and the convex pattern on the bottom surface of the concave portion can be formed on the material to make them stand out.

Embodiments of the present invention will be described below with reference to the drawings.

First, an example of the press mold used in the press molding method of the present invention will be explained.The press mold of this example has an upper mold 11))-T loaf U(')) as shown in FIGS. 1 and 2. )−
h) Put a punch (11), a die hole (12), and a movable mold (13) into the child's punch (1), and attach a die (21), a movable mold (22), and a punch to the lower mold (2). (23) is provided.

The punch (11) of the upper mold (1) is the die (2) of the lower mold (2).
1), four parts are formed on the metal plate material (a), and the cross section is rectangular as shown in FIG. 3, and the lower end is the stamped surface (Ila). This engraved surface <118)
A line pattern such as a mesh is formed on the bottom surface of the four parts formed on the material (a).

The die hole (12) of the upper mold (1) and the punch (23) of the lower mold (2) form a convex pattern, for example, a circular pattern, in a part of the area that will become the bottom wall of the recess of the material (a). in,
It consists of a hole with a circular cross section that is recessed from the lower surface of the punch (11), and a movable mold (13) is fitted inside the punch (13) so as to be vertically slidable.

The movable mold (13) is for pressing the convex pattern part of the material (a) from above, and is composed of a short cylinder and is attached to the holder (13).
4) is supported by the support shaft (15), and is supported by a spring (
16), and the lower end is in contact with the lower surface of the punch (11).

A material presser (17) (1g) for pressing the material (a) is attached to the upper die.

The die (21) of the lower mold (2) has a fixing block body (24
), and its molding hole (21a) is screwed to the upper mold (1).
The movable die (22) is vertically slidably fitted into the circumferential hole (21a).

The movable mold (22) presses the four parts of the material (a) from below, and has a rectangular cross section that is the same shape as the punch (11) of the upper mold (1), as shown in FIG. The flange (22a) of the step part (21a) is connected to the molding hole (21a).
b), and the fixing block body (24)
The die (21) is supported by a spindle (25) and a spring (26) and elastically biased upward, and its upper end is flush with the upper surface of the die (21). The lower surface of the movable mold (22) is spaced apart from the upper surface of the fixing block (24), and in this protrusion state, the movable mold (22) is stopped at the lower limit position.

The punch (23) of the lower mold (2) is inserted into the die hole (
It consists of a cylinder that matches the fixing block body (2).
4) is integrally protruded from the upper surface of the movable mold (22), passes through the movable mold (22) so as to be retractable from the upper surface thereof, and has an upper end that extends from the movable mold (22).
2) It is flush with the top surface.

Press molding using the press die as described above is performed as follows.

That is, a metal plate material (a) is placed between the upper mold (1) and the lower mold (2).
) by lowering the upper mold (1), the fifth
As shown in the figure, the material (a) has a recess (al), a line pattern on the bottom of the recess, and a circular convex pattern (al) protruding from the bottom.
and are formed at the same time.

The process of forming the recess (al) is that the punch (11) of the upper mold (1) contacts and presses the material, and at the same time the movable mold (22) of the lower mold (2) is pressed by the spring (26). The material (a) is strongly pressed against the punch (11) and the lower die (21) by the movable die (22) and is sheared between them (11) (21);
A recess (a+) with a sharp corner is formed in the material (a).

The line pattern on the bottom of the recess is the punch (11) in the upper die (1).
It is formed by the marking action of the marking surface on the lower end.

On the other hand, the process of forming the convex pattern (al) is the lower mold (2).
As the movable mold (22) lowers, the punch (23) of the lower mold (2) protrudes from the upper surface of the movable mold (22), and the punch (23) becomes the bottom wall of the recess of the material (a). At the same time as pressing a part of the area from below, the movable mold (13) of the upper mold (1) rises against the gun (16), and the material (a)
A part of the range is moved by the movable mold (13) to the upper mold (1).
While being strongly pressed against the die 1 (12) and the punch (23) of the lower mold (2), both of them (12)/')'J
Sp! 1 in front w1. A convex pattern (al) with four parts and one trowel is formed.

As an example of the use of the molded product obtained in the above manner,
As shown in Figures and Figure 7, materials for clips such as writing instruments (A
). A recess (a) formed in this material (A>
l) and the convex pattern (al) stand out from the surrounding board surface.

In addition, the engraved surface on which the line pattern on the bottom of the recess is engraved is the upper die (
The movable mold (2) of the lower mold (2) is not installed in the punch (11) of 1).
2) It may be provided on the top surface, or both (11) (22
) may be provided together.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view showing one embodiment of the press mold of the present invention, FIG. 2 is a cross-sectional view taken along the line (It)-<II) in FIG. 1, and FIG. III) Cross-sectional view of the track, Figure 4 is a cross-sectional view taken along the (IV)-(rV) line in Figure 1, Figure 5 is a vertical cross-sectional view showing the pressed material, and Figure 6 is an example of the application of the molded product. The plan view shown in FIG. 7 is a sectional view taken along the line (VI)-(Vl) in FIG. In the figure (a)...Metal plate material (al)...Concave part (a2)
)...Convex pattern (1)...Upper die (11)...Upper die punch (12)...Upper die hole (13)...Upper die movable (2)...・Bottom mold (2
1)...Lower die (22)...Lower movable die (23)...Lower punch Patent applicant Tokyo Kinzoku Seisakusho Co., Ltd.

Claims (1)

[Claims] ■ A metal plate material is sandwiched between an upper mold and a lower mold and pressed, and the upper mold is pressed while elastically pressing the material from below with a movable mold that fits on the inner periphery of the die of the lower mold. The punch and the die apply shear to the material to form a recess, and at the same time, a movable mold that fits into the die hole provided in the upper punch elastically modulates a part of the material that will become the bottom wall of the recess. A press molding method in which a part of the region is sheared by a punch passing through a movable mold of a lower mold and the die hole while pressing from above, thereby forming a convex pattern protruding from the bottom surface of the recess. ■ Consisting of an upper mold and a lower mold, the upper mold has a punch, a die hole recessed from the lower surface of the punch, and is fitted into the die hole so as to be able to slide vertically and is elastically biased downward. A movable mold is provided, and the lower mold has a die that matches the punch of the upper mold,
a movable mold that fits vertically slidably on the inner periphery of the die and is elastically biased upward; and a punch that penetrates the movable mold so as to be retractable from its upper surface and fits into the die hole of the upper mold. A press mold with a