JPS6336967A - Trimming die - Google Patents

Abstract

PURPOSE:To simplify the production stage and also to prevent the deformation of blade part by casting in the blade part of a trimming die together with a mold main body at casting and dividing the blade part at the circumferential direction of loop. CONSTITUTION:The lower mold 1 of trimming die is composed of the mold main body 2 and the blade part 3, which is integrately cast together with the main body, and the blade part 3 having the loop state is divided into the half bodies 3a, 3a. And, at the divided facing part of half body 3a, the gap (g) is formed and in the recessed part 4, a guide member 5 is inserted. At the time of casting the trimming die, the blade part 3 composing of high hardness steel is fitted to the expendable pattern having the same shape as the mold main body 2 and after investing the surround by refractory, molten metal is poured to cast in the blade part 3 in a ordinary cast iron. Therefore, the blade part is not fitted by the other stage, the production stage is very simplified and expansion of the blade part 3 at the time of casting is absorbed by the gap (g) and the deformation is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION (& Field of Application on Beams) The present invention relates to a trim die for press-cutting a board or the like into a predetermined shape using blades provided on the upper and lower dies.

(Prior Art) A trim type is known as a device for cutting iron plates or the like into a predetermined shape. This trim die generally consists of an F-type and an upper die that moves up and down relative to the lower die.The upper die is lowered toward the lower die, and the workpiece (object to be cut) is held down on the lower die by a band. In this state, the workpiece is pressed into a predetermined shape using blades provided on the upper and lower molds.

Since the trim-type blade part cuts iron plates and the like as described above, it needs to be made of high-hardness steel such as high-carbon steel. In consideration of machining, etc., it is preferable that the main body of the mold is made of ordinary cast iron, which has excellent inertia.

For this reason, conventionally, after the mold body is manufactured by casting, the blade portion is formed in the mold body by filling or inserting.

However, when the trim mold is manufactured by the above method, the blade portion must be formed as a separate process after the mold body is cast, which is disadvantageous in terms of production efficiency and cost.

Therefore, a technique disclosed in Japanese Patent Laid-Open No. 57-25278 is known.

JP-A-57-25276 discloses a mold (
A trim-shaped cavity (101) is formed in the interior of the runner (100), and a runner (102) communicates with this cavity (101).
, (+03) are formed separately, and one runner (103) is formed separately.
) from the other runner (+
From 02) onwards, molten metal (100) of high hardness steel was poured and trim molds made of materials with different material properties (hardness, toughness) were integrally cast.

(Problems to be Solved by the Invention) 1-As mentioned above, in so-called two-layer casting in which molten metal of materials with different properties is poured into a cavity through separate runners, each material is heat-treated after casting. In other words, high-hardness cast iron requires heat treatment at a higher temperature than normal cast iron, but it is difficult to heat treat each type under different temperature conditions, resulting in insufficient hardness and formation of cavities. Problems occur in the adjustment of metal structure such as generation.

(Means for Solving the Problems) In order to solve the above problems, the trim mold according to the present invention is made by integrally casting the trim mold by casting ordinary cast iron around a loop-shaped high-hardness steel material that will become the blade part. Furthermore, the blade portion was divided into at least two parts in the length direction of the loop.

(Function) When pouring metal with the blade set in the mold, the blade expands in the circumferential direction due to the heat of pouring, but this expansion is absorbed by the gap between the divided parts of the blade, and the blade expands. It does not deform in the radial direction and can be cast in the set state. In particular, if the split opposing parts are connected by a guide member that allows movement in the length direction of the loop, the L arrangement shape and the level difference between the split opposing surfaces can be further suppressed.

(Example) Examples of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows the lower mold of the trim mold according to the present invention, and shows the lower mold of the trim mold according to the present invention.
) An upper mold is placed above the mold so that it can be raised and lowered by a ram or the like. The lower mold (1) is made up of a mold body (2) and a blade part (3) which is integrally cast with this mold body (2). (3a), (
The second part is divided into 3a) and is an enlarged partial view of the 114th part.
As shown in the figure, a gap (g) is formed between each of the half-holes (3a) and the opposing divided portions of (3a).

It is desirable that this gap (g) be less than the thickness of the workpiece to be cut.

Further, as shown in FIG. 3, each of the half-rests (3a) and (3a) of the blade part (3) has a recess (4) in the length direction.

(4) is formed, and a guide member (5) is inserted into this recess (4) (4) to restrict the movement of each divided opposing part in the radial direction and to allow movement only in the length direction. ing.

A method for casting the lower mold (1) having the above structure will be explained based on FIG. 4.

First, a vanishing model (6) having the same shape as the lower mold body (2) is formed. The material used for the disappearing model (6) is one that vaporizes and disappears due to the heat of the molten metal, such as foamed resin. Then, the blade part (3) made of high hardness steel is attached to the vanishing model (6).
), and in this state remove the disappearing model (6) and the blade part (3).
is placed in a frame (7), and the surrounding area is hardened with a refractory material (8) such as sand containing a binder to form a mold.

Next, molten ordinary cast iron is supplied to the disappearing model (6). Then, the material of the disappearing model (6) melts and disappears due to the heat of the molten metal, the model (6) and the molten metal replace each other, and the blade part (3)
) is usually cast with molten cast iron.

Here, when the molten metal comes into contact with the blade part (3), the blade part (3)
temperature rises, the blade part (3) expands by 1, but the blade part (3) expands by 1.
) is composed of divided half-holes (3a) and (3a), and there is a gap (g
) is provided, and the split opposing parts are connected by a guide member (5) that is movable in the length direction of the blade, so expansion of the blade (3) occurs almost only in the length direction.
The blade does not shift in the radial direction.

In the embodiment, the blade portion (3) is divided into two halves, but it may be divided into more than two halves.

In addition, the temperature of the blade part (3) is raised before the molten metal that becomes the mold body comes into contact with the blade part (3), and the disappearing model (6 ) A heating element or a heat insulating material may be brought into contact with the blade part (3) exposed from the blade part (3).Furthermore, a preheating body made of a fugitive material is brought into contact with the blade part (3), and molten metal is poured into the part of the vanishing model (6). Before supplying, molten metal is supplied to the preheating body part using another runner, and the blade part (3)
The temperature may be increased.

(Effects of the Invention) As explained above, according to the present invention, when manufacturing a trim mold in which a blade is provided in the mold body, the blade is cast into the mold body, which simplifies the manufacturing process. The blade part is divided into a plurality of parts, and a gap is provided between the opposing parts of the IJ blade part, so that even if the blade part expands due to the heat of the molten metal during casting, this expansion is absorbed by the part of the gap. As a result, the blade part does not deform in the radial direction.
The blade portion can have a uniform overall profile.

[Brief explanation of drawings]

Fig. 1 is a perspective view of the lower mold of the trim mold according to the present invention, Fig. 2 is an enlarged view of the main part of the lower mold, Fig. 3 is a sectional view of the main part, and Fig. 4 shows the method of casting the trim mold. Fig. 5 is a sectional view of the conventional method. In the drawing, (1) is the lower mold of the trim mold, (2) is the mold body,
(3) is the blade part, (3a) is the half-rest of the blade part, (4) is the recessed part,
(5) is a guide member, (6) is a fire hydrant, and (g) is a gap.

Claims (2)

[Claims] (1) In a trim mold in which a mold body made of cast iron is provided with a blade part made of a steel material with higher hardness than the mold body and having a loop-like overall shape, the blade part is cast into the mold body. A trim type characterized in that the blade part is divided in the circumferential direction of the loop. (2) A recess is formed in the split opposing portion of the blade in the length direction of the blade, and by inserting a guide member into this recess, the split opposing portion is connected so as to be movable in the length direction. A trim mold according to claim 1, page 1, item 1, characterized in that: