JPS6192737A - Punching die - Google Patents

Abstract

PURPOSE:To prevent a die body from being broken and cracked by diving the die body on a surface passing through other axis being in parallel to its center axis. CONSTITUTION:A die body 2 having a die hole 1 is fitted and fixed into a cylindrical ring bush 3, and its ring bush 3 is fitted and fixed into a die holder. The die body 2 is constituted of two kinds of total four nibs 5, 6, one nib 5 has a formed surface 5a of a long side part of a rectangle, and the other nib 6 has a formed surface 6a of a circular arc part. Also, an opposed contact surface between each nib 5, 6, namely a split surface of the die body 2 is positioned on a plane passing through a split axis Q positioned at both sides of a center axis P of this die body 2 in the die hole 1. Therefore, angles of corner parts of each nib 5, 6 become almost equal. Accordingly, a pressure between the outside peripheral surface of the nibs 5, 6 and the ring bush 3 becomes almost equal over the whole periphery, an internal pressure is dispersed equally, and a crack, etc. in the corner parts of each nib 5, 6 are prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Field of Industrial Application) The present invention relates to a punching die that can die-process a product of a predetermined shape by punching.

(Prior Art) Conventionally, in this type of die, there is one in which the die body is formed in sections to prevent cracks from occurring in the die body due to internal pressure during punching.

(Problems to be Solved by the Invention) However, this conventional split die is divided on a plane passing through the central axis of the die body.

Therefore, depending on the shape of the mold cavity of the die body, cracks or chips may occur at or near the dividing portion.

This invention attempts to solve this problem.

(Means for Solving the Problems) Therefore, in the present invention, the die body is divided on a plane passing through another axis parallel to the central axis of the die body.

(Example) Hereinafter, a first example embodying the present invention will be described based on FIGS. 1 and 3. A die body 2 having a mold cavity 1
is fitted and fixed into a cylindrical ring bushing 3, and the ring bushing 3 is fitted and fixed into a die holder 4.

The mold cavity 1 has a rectangular shape with arcuate ends. Further, the die body 2 is composed of a total of four nibs 5 and 6 of two types. One nib 5 has a forming surface 5a that is a long side of a rectangle, and the other nib 6 has a forming surface 6a that is an arcuate portion. Further, the contact surface between each nib 5 and 6, that is, the dividing surface of the die body 2 is located within a plane passing through the dividing axis Q located on both sides of the central axis P of the die body 1 in the mold cavity 1. ing. Therefore, the angles of some of the corners of each nib 5, 6 are approximately the same.

Therefore, the pressure between the outer circumferential surface of the nib 5.6 and the ring bush 3 based on the internal pressure during punching becomes almost the same over the entire circumference, and the internal pressure is evenly distributed, resulting in This prevents omissions, etc.

FIG. 2 shows a second embodiment of the present invention, which differs from the first embodiment in that the shape of the mold cavity 1 is approximately D-shaped, and its function is This is the same as the first embodiment. 8 and 9 indicate nibs.

Effects of the Invention As exemplified in the embodiments above, the present invention has the effect of preventing cracking and chipping of the die body.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing a first embodiment embodying the present invention, FIG. 2 is a plan view showing a second embodiment, and FIG. 3 is an exploded perspective view showing the first embodiment. Mold hole 1, die body 2, ring bush 3, die holder 4, center axis P, division axis Q, patent applicant Sumikin Seisatsu Co., Ltd.

Claims (1)

[Claims] 1. A punching die in which a die body (2) provided with a die hole (1) is housed in a die case (7), comprising: A punching die characterized in that it is divided on a plane passing through another axis (Q) parallel to the central axis (P) of the punching die. 2. The die case (7) is constituted by a ring bush (3) that accommodates the die body (2) and a die holder (4) that accommodates the ring bush (3). The punching die described in . 3. The punching die according to claim 1, wherein the axes (Q) are a pair. 4. The punching die according to claim 3, wherein the axis (Q) is located within the mold cavity (1). 5. The punching die according to claim 3, wherein the axis (Q) is located on both sides of the central axis (P). 6. The punching die according to any one of claims 3 to 5, wherein the mold cavity (1) has a substantially rectangular shape. 7. The punching die according to any one of claims 3 to 5, wherein the mold cavity (1) is approximately D-shaped.