JPH08141666A - Resin made press die and its production - Google Patents

Abstract

PURPOSE: To provide a resin made press die which can secure sufficient pressure resistance strength only for required part in resin layer, improves durability and is suitable for mass production and its production method. CONSTITUTION: A cast iron made insert member 26 is embedded in a part corresponding to the shoulder part requiring pressure resistance strength to a resin layer 24 constituting the forming face 20 of a punch 18 and this insert member 26 forms part of the forming face 20. On the other hand, a cast iron made insert member 40 forming part of a forming face 34 is embedded in a part corresponding to the bent part requiring pressure resistance strength of a resin layer 38 constituting the forming face 34 of die 32.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin press die in which a resin layer is provided on the molding surface of the press die, and a method for producing the same.

[0002]

2. Description of the Related Art In recent years, a resin-made press die having a resin layer on its forming surface has been widely adopted as a press die used for pressing metal materials. In this type of resin-made press die, it is desired to secure the pressure resistance required for performing press forming such as bending and drawing on a metal material.

Therefore, as disclosed in Japanese Patent Publication No. 59-11370, a press molding surface is provided with a synthetic resin coating layer, and the synthetic resin coating layer contains cast iron powder. A press die is known in which a part of the cast iron powder is exposed on the surface of the synthetic resin coating layer (hereinafter referred to as Conventional Example 1). Further, as disclosed in JP-A-6-71356, a resin press mold in which a thermosetting resin sheet is attached to a part of the resin layer of the press mold and the resin sheet is heated to be thermoset. Is known (hereinafter referred to as Conventional Example 2).

[0004]

However, in the above-mentioned conventional example 1, the cast iron powder cannot be concentrated and added only to the portion of the synthetic resin coating layer where the pressure resistance is required, and a large amount of unnecessary iron powder is unnecessary. Cast iron powder will be added. Moreover, since cast iron powder is added to the synthetic resin coating layer, it has limited durability and is suitable for a prototype mold, but it has been pointed out that it cannot be actually used as a press mold for mass production. ing.

Further, in the above-mentioned conventional example 2, since the thermosetting resin is provided only in the portion of the resin layer which requires the compressive strength, it is possible to improve the compressive strength as compared with the conventional example 1.
There is a problem that durability is limited and it is not suitable for mass production press dies.

The present invention solves this kind of problem, and it is possible to secure sufficient pressure resistance only in a necessary portion of the resin layer, and at the same time, the durability is improved and the resin is suitable for mass production. An object is to provide a press-making die and a method for producing the same.

[0007]

In order to solve the above-mentioned problems, the present invention is a resin press die in which a resin layer is provided on the molding surface of the press die, wherein the resin layer has a compressive strength. The cast iron insert member is embedded corresponding to only the portion that requires, and the surface of the cast iron insert member forms a part of the molding surface.

Further, the present invention relates to a resin-made press die for producing a press die in which a void is formed between a press die body and a base die, and a resin is injected into the void to provide a resin layer on a molding surface. A manufacturing method, in the resin layer, a step of obtaining a cast iron insert member having a shape corresponding to a portion requiring pressure resistance, and forming a void between the press die body and the base die. A step of disposing the insert member at a desired position of the void, and a step of injecting a resin into the void in which the insert member is disposed to form a resin layer in which the insert member is embedded. Is characterized by.

[0009]

In the resin press die and the method of manufacturing the same according to the present invention, first, a cast iron insert member having a shape corresponding to a portion of the resin layer that requires pressure resistance is prepared, and the insert member is used as a molding surface. It is embedded in the resin layer as a part. Therefore, the compressive strength of the resin layer is sufficiently secured only in a desired portion by the insert member, and moreover,
Durability is effectively improved.

[0010]

EXAMPLES The resin press mold and its manufacturing method according to the present invention will be described in detail below with reference to the accompanying drawings.

In FIG. 1, reference numeral 10 indicates a resin press die according to this embodiment. The press die 10 includes a fixed lower die 12 and an upper die 14 that can move up and down above the lower die 12.
With.

The lower die 12 has a fixed punch mounting portion 16
And a punch 18 screwed onto the punch mounting portion 16, and the punch 18 has a recess 22 on all or part of its molding surface 20. A resin layer 24 of synthetic resin that integrally forms the molding surface 20 is formed in the concave portion 22 of the punch 18, and the resin layer 24 requires pressure resistance, that is, the shoulder portion of the punch 18. The cast iron insert member 26 forms a part of the molding surface 20 and is embedded only in the portion corresponding to.

Bolts 28 are integrally screwed into the insert member 26, the resin layer 24 and the punch 18, whereby the insert member 26 and the resin layer 24 are firmly fixed to the punch 18.

The upper die 14 is a die mounting portion 30 that can be raised and lowered.
And a die 32 screwed to the lower side of the die mounting portion 30. The die 32 has a recess 36 on all or part of its molding surface 34. Recess 3 of die 32
6 is provided with a resin layer 38 of synthetic resin that integrally forms the molding surface 34, and this resin layer 38 corresponds to a portion requiring pressure resistance, that is, a bent portion of the die 32. Insert member 40 made of cast iron only in the part
Are partially embedded in the molding surface 34.

A bolt 42 is integrally screwed into the insert member 40, the resin layer 38 and the die 32, whereby the insert member 40 and the resin layer 38 are firmly fixed to the die 32.

Next, the press die 10 constructed as described above.
The process of manufacturing the punch 18 will be described first.
And an insert member 26 having a shape corresponding to a portion of each of the resin layers 24, 38 of the die 32 that requires compressive strength.
40 are manufactured. The work of manufacturing the insert member 26 will be described in detail below.

As shown in FIG. 2A, in the master model 50, which is made of wood or gypsum corresponding to the punch 18, the gypsum 54 is attached to the shoulder 52 that requires pressure resistance. Next, after the plaster 54 is separated from the master model 50 and the clay 56 is attached to the recess 54a of the plaster 54, the plaster 54 is covered so as to cover the clay 56.
Gypsum 58 is attached to the base (see FIG. 2B).

Further, when the plasters 54 and 58 are solidified and then the clay 56 is removed by separating them, the plaster 5
4, 58 are heated to remove water. And
As shown in FIG. 2C, the gypsum 54 or the gypsum 58 has a sprue
0 is provided, and the plasters 54 and 58 engage with each other to form a cavity 62 corresponding to the shape of the clay 56. Therefore, the molten cast iron (FC) is injected into the cavity 62 from the sprue 60, and after a lapse of a predetermined time, the gypsum 5
By separating 4, 58, the cast iron insert member 26 is obtained (see FIG. 2D).

The insert member 40 of the die 32 is
It is obtained by the same manufacturing method as the above-mentioned insert member 26, and detailed description thereof will be omitted.

Next, a process of manufacturing the punch 18 and the die 32 will be described.

First, the punch 18 is cast by, for example, a full molding method. As shown in FIG. 3, this punch 18 has a sprue 64 for injecting a synthetic resin into the recess 22.
Is provided. On the other hand, as shown in FIG.
For example, it is cast by a full molding method and the recess 36
A sprue 66 for injecting synthetic resin is provided.

The bottom surface (reference surface) of the punch 18 and the die 3
The upper surface (reference surface) of 2 is processed, and the punch 18 and the die 32 are profiled. Further, after the punch 18 and the die 32 are circumferentially rubbed with each other, the recesses 22 and 36 are degreased by a thinner or the like.

Then, a reverse die model 68 for punching is manufactured from plaster or synthetic resin based on a punching master model (not shown) (see FIG. 5). The reversing die model 68 is arranged in a reversing state, and the insert member 26 is easily releasably adhered to a corner portion thereof, that is, a position corresponding to the shoulder portion of the punch 18. Then, the punch 18 is assembled in the inverted die model 68 in the inverted state, and is fixed to each other by the clamp means (not shown). As a result, a cavity 70 is formed between the recess 22 of the punch 18 and the reverse die model 68.

Next, when the synthetic resin mixed with the curing agent is injected into the cavity 70 of the punch 18 through the sprue 64, the synthetic resin is cured and the resin layer 2 is formed in the recess 22.
4 is formed. At that time, the insert member 26 arranged in the cavity 70 is embedded in the resin layer 24. Then, the punch 18 and the reverse die model 68 are separated.

As shown in FIG. 6, the punch 18 on which the resin layer 24 is formed has a thickness corresponding to the plate thickness of the work W after press molding by the press die 10 and is made of, for example, wax or the like. 72 is attached to the molding surface 20. The insert member 40 is attached to the master sheet 72 at a position corresponding to the bent portion of the die 32 so as to be easily peelable. A release agent is applied to the surface of the master sheet 72 in advance.

Further, the punch 18 is attached to a blank holder plate (not shown), and after the punch 18 is centered, the die 32 is attached to the punch 18 (see FIG. 6). Therefore, the recess 3 of the die 32
A cavity 74 is formed between the master sheet 6 and the master sheet 72, and a synthetic resin containing a curing agent is injected into the cavity 74 from the sprue 66. This allows the die 32
A resin layer 38 is formed by burying an insert member 40 in the recess 36.

Next, the punch 18 and the die 32 are separated from each other, and the master sheet 72 is removed.
8 and die 32 are finished. Then, the punch 18 is screwed to the punch mounting portion 16 and the die 32 is screwed to the die mounting portion 30, and the manufacturing work of the press die 10 is completed.

The insert member 26 and the resin layer 2
4 is fixed to the recess 22 of the punch 18, the bolt 28 is integrally screwed into the insert member 26, the resin layer 24 and the punch 18, and then the head of the bolt 28 exposed to the outside of the resin layer 24. Cut the part side and finish with a file etc. A knock pin (not shown) may be driven in if necessary. On the other hand, the bolt 42 that fixes the insert member 40 and the resin layer 38 to the recess 36 of the die 32 is processed in the same manner as the above-described bolt 28.

In the press die 10 according to this embodiment manufactured in this manner, the resin layer 24 forming the molding surface 20 of the punch 18 is required to have pressure resistance, that is, the shoulder portion of the punch 18. A cast iron insert member 26 is embedded in the portion to be formed, and this insert member 26 forms a part of the molding surface 20.

Therefore, there is no problem of adding a large amount of cast iron powder to an unnecessary portion unlike the conventional resin layer containing cast iron powder, and the insert member 26 is provided only in a portion requiring pressure resistance. Can be provided. Therefore,
The effect that the pressure resistance hardness of the resin layer 24 can be improved at once is obtained. Moreover, since the cast iron insert member 26 having a desired shape is used instead of adding the cast iron powder to the resin layer, the durability is improved and the punch 18 has a considerably long life, which is suitable for mass production. There are advantages. Since the insert member 40 is provided also in the die 32 corresponding to the portion where pressure resistance is required, the same effect as the punch 18 can be obtained.

[0031]

As described above, according to the resin press die and the method for producing the same according to the present invention, the following effects can be obtained.

In the resin layer constituting the molding surface of the press die,
Since the cast iron insert member is embedded in the portion requiring the pressure resistance, the pressure resistance of the resin layer is sufficiently secured only in the desired portion by the insert member.
As a result, the durability is improved all at once and it can be effectively used as a press mold for mass production.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a press die according to the present invention.

FIG. 2 is a diagram illustrating a manufacturing process of an insert member that constitutes the press die, FIG. 2A is an explanatory diagram of a state where plaster is attached to a master model, and FIG. 2B is a diagram in which clay is surrounded by two plasters. 2C is an explanatory view of a state in which a cavity is provided between the two plasters, and FIG. 2D is an explanatory view of an insert member manufactured by pouring cast iron into the cavity.

FIG. 3 is a vertical cross-sectional explanatory view of punches forming the press die.

FIG. 4 is a vertical cross-sectional explanatory view of a die forming the press die.

FIG. 5 is a partially enlarged vertical sectional view showing a state where cavities are formed by a punch and a reverse die model.

FIG. 6 is a partially enlarged vertical sectional view showing a state in which the punch and the die are assembled to form a cavity.

[Explanation of symbols]

10 ... Press mold 12 ... Lower mold 14 ... Upper mold 16 ... Punch mounting part 18 ... Punch 20, 34 ... Molding surface 22, 36 ... Recessed part 24, 38 ... Resin layer 26, 40 ... Insert member 32 ... Die

Claims (2)

[Claims] 1. A press mold made of resin in which a resin layer is provided on a molding surface of the press mold, wherein a cast iron insert member is embedded in the resin layer so as to correspond only to a portion requiring pressure resistance. In addition, the surface of the cast iron insert member forms a part of the molding surface, and a resin press die. 2. A method for producing a resin press die, in which a gap is formed between a press die body and a base die, and a resin is injected into the void to produce a press die having a resin layer on a molding surface. A step of obtaining a cast iron insert member having a shape corresponding to a portion requiring pressure resistance in the resin layer, and forming a void between the press die main body and the base die, and A step of disposing the insert member at a desired position, and a step of injecting a resin into the space in which the insert member is disposed to form a resin layer in which the insert member is embedded. A method for manufacturing a resin press die.