SU761079A1 - Die for punching openings in flat parts - Google Patents

Description

The invention relates to tooling for cold forming, can be used in the radio industry mainly in the manufacture of printed circuit boards, as well as 5 and in other areas when punching holes in products made of plywood, wood, plastic.

Known stamp [1], containing the upper and lower plates, a matrix, punches, ₁₀ means for directing punches in the form of figured washers, in the end planes of which along the periphery there are notches. Between the washers in the cavities formed by the recesses ₁₅ are situated Belleville pru- zhiny. Washers with springs are installed in the cavity formed by two sectors that have protrusions and can move relative to each other.

Disadvantages of the stamp yavlya- ₂ are about the complexity of manufacturing curved washers sectors with projections, as well as the complexity of its installation. Stamping a group, e.g., printed circuit boards, when breaks up to several hundred holes ₂₅ po- Daubney stamp not only difficult to implement due to the complexity of the die, but also because of the required small distance between the punches (of the order of 3 mm or less), since such small size-39

2

It is difficult to make figured washers, cup springs, sectors with protrusions and to ensure their reliable operation.

Known stamp for punching holes in the sheet material holes with a diameter, minicim the thickness of the material containing the puller, consisting of several members of one another and glasses and columns guided punch [2].

In the well-known stamp, the need for relative centering of the glasses requires a higher precision in their manufacture.

Known stamp for punching holes in flat products, in particular in printed circuit boards, containing a movable plate, punches, a puller, guide punches and made in the form of plates arranged one below the other and relatively movable in the direction of movement of the punch, and a fixed plate carrying the matrix. In the well-known stamp, the puller is not directed relative to the plates and has a non-rigid structure, which reduces the accuracy of the direction of the punches [3].

To increase the rigidity of the puller and increase the accuracy of the direction of the punches, the stamp is provided with a puller direction node, made in the form of frames and clips entering one another, one of which is

tory fixed on the plate of the puller, placed on the side of the working ends of the punches, and the other on the movable plate of the stamp.

To press the product during punching, the stamp can be equipped with elastic elements placed between the plates and between the frame and the yoke.

FIG. 1 shows a stamp in longitudinal section; in fig. 2 — section A — A of FIG. one.

The stamp consists of the lower fixed plate 1, on which the matrix 2 and the slider 3 bar are installed. Columns 4 are mounted in the bottom plate 1, along which the upper movable plate 5 moves. On the top plate 5 are mounted a ferrule 6, an elastic element 7 (for example from polyurethane), pins 8 with fasteners, a punch holder 9. Made in the form of flat plates 10, a puller for directing the punches 11, the elastic elements 12 and the puller plate 13, provided with a plate 14 and connected to the frame 15, placed on the side of the working ends of the punches 11. The plate 5 is equipped with a shank 16, a cover 17 of the hatch with fasteners for access to the punches 11, gaskets 18. The frame 15 is placed in the holder 6.

Works stamp as follows.

When the press ram moves downwards, the board 19 is clamped using a stripper strip 14, the force to which is transmitted from the element 7 acting on the frame 15. The puller is guided by the frame 15 moving in the casing 6. With the further movement of the press ram downwards, the holes are punched 19 with punches. 11. At the same time, elastic elements 12 are compressed. After punching the holes, elements 7 and 12 take on their original shape, the stamp takes up its original position. To prevent displacement of the elements 12, they can be glued to the plates 10 for the direction of the punches.

The direction of the puller using the frame and the holder allows you to provide the necessary rigidity of the puller and uniform clamping of the printed circuit board. The implementation of means for directing punches in the form of flat plates mounted on pins connected to the upper plate allows to simplify the stamp design and ensure a large stroke of punches without the danger of their buckling and loss or stability, since the distance between the flat plates in the initial position of the stamp can be provided structurally small enough.

Since the proposed stamp allows a large stroke of punches, it can be used for group stamping and punches with a conical shape of the working part and a rounded end. During the experiments, such punches, although they have reduced strength, require complex sharpening, allow for a significant depth of foil tightening into the punched hole, which significantly increases the reliability of the solder joints.

The stamp, providing a large stroke of punches, can also be used for group punching of small-sized holes in thick plates, for example, in plywood, wood, plastic.

Claims (2)

Claim 1. Stamp for punching holes in flat products, in particular printed circuit boards, containing a movable plate, punches and a puller, guiding punches and made in the form of plates arranged one below the other and relatively movable in the direction of movement of the punch, characterized in that increase the rigidity of the puller and improve the accuracy of the direction of the punches, it is equipped with a puller direction assembly, made in the form of frames and clips entering one another, one of which is fixed on the puller plate placed on the sides the working end of the punches, and the other - on the moving platen die. 2. Stamp on π. 1, characterized in that, in order to implement the clamping of the product, it is equipped with elastic elements placed between the plates and between the frame and the yoke.