JP2007105791A - Trimming die - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mold with which manufactured goods the sheared face of which is lengthened and which are excellent in shape accuracy such as a camber and a round edge are produced at high productivity. <P>SOLUTION: In this mold, a die is arranged on one side of the upper mold and the lower mold and integrated or divided punches which are paired at a prescribed width (w), a blank holder, a blank holding spring are arranged on the other side and the contour of a product is blanked with the inner part or the outer part of the punch. In the mold, one more blanking contour is provided in the position of the width (w) along the contour of the product. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to a mold for punching a plate material and a press working method.

In order to obtain a product with a slanting and burr at the entire shear surface, excellent perpendicularity and flatness with respect to the plate surface of the work piece cut, the punch and die have been conventionally used by general-purpose press working. Although a punching die with a small clearance is used, it is difficult to obtain a long shear surface, and there is a limit to improving the shape accuracy such as large burr and squareness.
Therefore, using a dedicated double-acting press machine, the punching clearance is reduced, the plate presser force is increased, the counter force facing the punch is added, and a V-shaped ring is provided on the plate presser to increase the compressive stress near the cutting edge and crack There is a way to prevent the occurrence of

Problems to be developed by the invention

In the conventional method using a general-purpose press machine, it is not possible to obtain a total shearing surface with a hard material, and the shape and shape accuracy of the workpiece cut such as warpage, die mark, burr, drooping, perpendicularity to the plate surface, etc. Inferior.

In the method using a dedicated double-acting press machine, both the press machine and the mold are complicated and expensive. Moreover, since the number of strokes per minute of the press machine is low, the productivity is low, and the pressurization range is limited, it is difficult to process a processed product that requires multi-stage progressive feeding with a wide pressurization range. It is difficult to stably obtain a workpiece cut shape for a hard material.

Means to solve the problem

When punching a plate material, another punching contour is provided at the position of the width w along the product contour to prevent a decrease in the compressive stress in the plate material near the cutting edge or to increase the compressive stress.

An integral or split punch is provided that is paired with a width w along the product contour.

With this pair of punches, the material blocked between the punches is constrained by the compressive force from both of the paired punches due to the penetration of the punches, and at the same time the material under the paired punches corresponds to this punch ( Width w + extraction clearance) When pressed into a die having a width, a compressive force is applied from the side wall of the die.

While receiving the compressive force, the material under the punch is rotated under the punch due to the frictional resistance caused by the compressive force generated on both side walls of the die and prevents one end of the material under the punch from being separated from the punch.

The material to be processed between the punches in a pair and the material to be scrap under the width w are separated by the approach of the cutting edges of both the punch and the die, but the compressive force generated in the material and the material under the punch By preventing the compressive force from being reduced by suppressing the rotational moment, the reduction of the compressive stress in the vicinity of the punch, die and cutting edge is prevented or the compressive stress is increased to suppress the generation of cracks and improve the shape accuracy.

When the contour of the workpiece is an outer shape, a punch with a width w is provided on the outer side, and when the contour of the workpiece is a hole, a punch with a width w is provided on the inner side.
The width w does not need to be constant and can be partially changed according to the shape of the processed product. Also, the outline can be used around the entire circumference or partially.

Use a general-purpose press to improve productivity.

An embodiment of the invention will be described based on an example with reference to the drawings.
In FIG. 1, a punch 1, a plate presser 2, and a plate presser spring 3 are provided on the upper die, and are fixed to a punch plate and a punch holder. A die 4 is provided on the lower die and is fixed to the die holder.

FIG. 1 shows a stage in the middle of punching. Between the opposing punches 1, a material to be processed 5, a material to be scrap A 6 under the punch 1, and a material to be scrap B 7 are punched outside the punch 1.

The punch width w12, clearance c13, and punch r14 are selected according to the material to be processed and the plate thickness. In Examples, steels having a carbon content of 0.4% or more were set to w = t, c = 0.3% t and r = 7% t, respectively.
The plate presser spring was set to 20% or more of the punching force.

FIG. 2 shows an example of a workpiece contour.
When punching is performed with the punch 1 having the width w along the contour of the workpiece 5 having the punching contour surrounded by the curve, the scrap A6 having the width w12 along the contour and the scrap B7 are generated outside the scrap A6.

Since the present invention is configured as described above, the following effects can be obtained.

The features of the processed product obtained by the present invention will be described with reference to FIG.
At the cut end of the processed product, a smooth full shear surface 8 having no fracture surface is obtained, and the sled 9 and burr 10 are small. Further, the warp 11 of the entire processed product is small, and the perpendicularity 15 is excellent.

It is effective in obtaining a crack-free shear surface with a hard material such as high carbon steel.

A general-purpose press machine enables high-speed punching and multi-stage progressive processing, resulting in good productivity.

1 is a cross-sectional view of a punching die according to an embodiment of the present invention. It is explanatory drawing of the product and scrap by the cutting die of this invention Example. It is explanatory drawing of the workpiece cut obtained by this invention.

Explanation of symbols

1 Punch 2 Plate retainer 3 Plate retainer spring 4 Die 5 Processed product 6 Scrap A
7 Scrap B
8 Shearing surface 9 Who 10 Debris 11 Sleigh 12 Punch width w
13 Clearance C
14 Punch cutting edge r

Claims (3)

A die is placed on either the upper die or the lower die of the mold, and an integrated or divided punch, plate presser, or plate presser spring that forms a pair with a predetermined width (w) is placed on the inside of the punch. , Or the mold that draws the product outline on the outside, The mold according to claim 1, wherein another punching contour is provided at the position of the width w along the product contour. The width w provided along the contour is 50% to 150% with respect to the plate thickness t of the workpiece, and the punch and die clearance c is 0.2% to 5% with respect to the plate thickness t. The die according to claim 1 or 2, wherein the cutting edge r at the tip is 2% to 15% with respect to the plate thickness t.

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