RU1794545C - Stretching die - Google Patents

Abstract

The invention relates to the processing of metal by pressure, in particular to sheet stamping, and can be used for the manufacture of convex-concave shapes. The purpose of the invention is to save sheet metal and improve product quality. The stamp consists of a lower fixed plate with a matrix fixed to it, convex in the longitudinal direction, a clamp made of two opposite vertically movable blocks with restrained thresholds mounted on backpressure devices and guides. The upper half of the stamp consists of a punch with a corresponding concave angle and a clamping ring With constricted elements corresponding to the bottom plate. The height of the movable blocks is equal to the height of the fixed blocks at their junctions. 6 ill.

Description

ate

WITH

The invention relates to the field of sheet punching and can be used to shape convex-concave parts such as an inner panel of a tailgate, an inner panel of a trunk lid of a passenger car.

A stamp with stretching on double-acting presses is known, comprising a die located in the lower part and a clamp with taper ribs, a punch and a pressure ring fixed in the upper part, as well as a back pressure device.

The disadvantage of this stamp is the possibility of obtaining parts of a convex-concave shape, which on two opposite sides do not require a blank of the blank along the punch, but only a deep drawing on these sides near the edges is required.

The aim of the invention is to save sheet metal and improve the quality of convex-concave products.

To achieve this goal, the clamp is made integral from two movable blocks located on both sides of the axis of the stamp and placed between the two fixed blocks, while the heights of the blocks in the mating zones are respectively equal.

In FIG. 1 is a plan view of a matrix; in FIG. 2 - longitudinal section of the stamp at the moment of pressing the transverse sides of the workpiece and the beginning of the wrapping; in FIG. 3 - stamp at the end of the wrapping and pressing the workpiece around the perimeter; in FIG. 4 - stamp at the time of completion of shaping; in FIG. 5 and 6 is a transverse section of the stamp at the end of the wrapping and clamp for

4 SL 4 SL

perimeter cooking, as well as at the time of forming.

The stretching stamp contains a fixed plate 1 with a matrix 2. The lower clamp consists of movable blocks 3 mounted on back pressure devices 4 and guides 5 located on the longitudinal sides of the workpiece, as well as fixed blocks made in one piece bottom plate 1 and located on the longitudinal sides of the workpiece. To brake the flange of the workpiece, brake ribs or sills are made on the pressure blocks. The connectors of the movable and fixed blocks at their mating points are designated 6, and the points on the opening of the blocks at their mating points are 7 and 8. The upper part of the stamp contains a clamp 9 mounted on the plate 10 and a punch 11.

The stamp works as follows.

The preform 12 is stacked on the protruding part of the matrix 2 and the movable blocks 3 in the upper position. The height of the points 7 on the opening of the moving blocks in the places of their mating 6 with the fixed blocks - Нп will be greater than the height of the points 8 on the opening of the moving blocks Нн by the stroke of the backpressure device - L. During the course of the external press slide (not shown), the clip is 9 s the plate 10 lowers and presses the flanges of the transverse sides of the workpiece 12 to the movable blocks 3. With the further course of the external slider, the workpiece 12 is wrapped along the matrix 2, starting from its top. which creates favorable conditions for its uniaxial longitudinal extension. To effectively stretch the workpiece 12 at

Claims (1)

SUMMARY OF THE INVENTION A stamp for stretching on double-acting presses comprising a die located in the lower part and a clamp with taper ribs, a punch and a pressure ring fixed in the upper part, and a counter-pressure device, characterized in The radius of the vertex of the matrix RM must exceed the size (10-15) Z, where Z is the gap between the matrix 2 and the punch 11. When the outer slider reaches bottom dead center there is a clamping of the longitudinal sides of the workpiece 12 with a clamp 9 and fixed blocks. In this position, the flanges of the workpiece 12 are clamped around the perimeter, and the height Hp will be equal to the height of HH along the line of their mating 6 until the end of shaping. During the course of the internal press slider (not shown in the drawing), the punch 11 is lowered and acts on the workpiece with its protruding parts made along its perimeter. The parts are drawn and formed. In order to conduct a successful shaping process with a maximum stretching of the workpiece 12 and the absence of corrugations and undulations on the surface of the part when drawing with a concave punch 11 (at ), protruding elements with a height of HB (5-7JZ, an angle with a concave apex of the punch 11 / 40-80 °, a radius of curvature of the tip of the matrix RM of at least (10-15) Z, are made along the perimeter of the punch, The most efficient use of the described stamp for the manufacture of parts of a convex-concave shape, i.e. those in which the direction of curvature of the main surface is opposite to the direction of local protrusions. This saves sheet metal by reducing technological allowances and improving quality by eliminating corrugations and undulations on the part. that, in order to save sheet metal and improve the quality of convex-concave products, the clamp is made of two movable blocks located on both sides of the die axis and placed between the two fixed blocks, while the heights of the blocks in their mating zones are respectively equal . .2