SU101055A1 - Method of drawing hollow sheet metal products - Google Patents

Description

A distinctive feature of the proposed method of pulling hollow articles from sheet metal in a stamp with a pressure ring is a message to the pressure ring in the process of working movement of the exhaust punch of reciprocating (pulsating) movements along the axis of the punch, which ensures smoothing of folds on the flange part of the product to be pulled and increase EXTRACT RATE in one operation.

FIG. 1 shows the beginning of the stretching according to the proposed method; in fig. 2 and 3 - the process of wrinkling on the flange part of the product; in fig. 4 - the process of smoothing the folds.

In a stamp consisting of a punch / with a pressing ring 2, a hollow product is drawn out of the SHEET blank 3 located on the stretch ring of the die 4.

The clamping ring 2 is at a certain distance f from the workpiece at the time of the beginning of the EXTRACT. As a consequence, the folding of the flange part of the workpiece occurs, and the height of the folds cannot exceed the values of the gap between the matrix 4 and the clamping ring 2 (Fig. 2 And 3). Then

the movement of the pressure ring 2 is reported to be DOWN. And under the action of its EFFORT the folds on the flange part of the product being stretched are smoothed (Fig. 4). After the folds are smoothed, the pressure ring 2 again rises to the height f (or to another height) and when the punch is moved / down, the material of the flange part of the workpiece 3 is folded again. This time the height of the folds also cannot exceed the values / the gap between the die 4 and the pressure ring 2. When the pressure ring is lowered, the folds on the flange part of the product being pulled out are again smoothed. A reciprocating motion is thus reported to the pressure ring 2 until the process ends.

In the proposed method of stretching, the force from the punch side / is expended only to overcome stresses from friction at the extruded edge of the die, to provide wrinkles in the flange portion of the product being stretched and to bend the material around the stretch edge of the die, and plastic deformation of the flange of the workpiece This is due to the landing of the hofp when lowering the clamping ring 2. The stresses from the friction, as well as the plastic deformation stresses, are practically absent, which makes it possible to engage in plastic deformation significantly larger material volume and thus dramatically increase the coefficient of stretching in a single operation. It is quite obvious that from the point of view of increasing labor productivity, it is necessary in the process of inserting the punch / with deformable workpiece 3 into the stretch ring of the matrix 4 to report pulsating displacement to the clamping ring 2 with a well-defined pulsation amplitude. Amplite} and pulsation is established depending on the geometrical dimensions and mechanical properties of the material being stamped with the aim of ensuring the fit of the resulting CI to stretch the folds under the influence of force from the side of the ring.

Subject and reason about cm i and

A method of stretching hollow articles from sheet metal in a stamp with a PRESSURE ring, characterized in that, in order to increase the stretch ratio in one operation, the pressure ring during the stroke of the punch is reported to reciprocate (pulsate) s along the axis of the punch.

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