CS199366B1 - Production method of fine perforated thin-walled grid - Google Patents

Description

The present invention relates to a method for producing a fine-perforated thin-walled grid with a one-sided beading of openings, e.g.

The fine-perforated thin-walled grille, for example as a fixed knife, on whose inner surface the movable knife of an electric shaver vibrates, is still produced by etching or electroplating, so-called galvanoplasty.

At present, fine holes in the thin-walled grid are also produced by punching, stretching and machining, and it is known to use an elastic environment for forming operations.

The production of etching grids for electric shavers is very lengthy and laborious and does not guarantee quality products, as burrs are formed on both sides of the etched holes.

Thin-walled fine-mesh grills with galvanoplastic are superior, but expensive to manufacture and have a low lifetime in service.

The punching and stretching holes created in thin-walled grids are geometrically more accurate and the products are of better quality and less laborious. However, punch waste is very difficult to remove due to its small size. If it sticks to some parts

199 366

199 388 tools, will cause difficulty in stretching, or cause scrap.

The described drawbacks of the known technology are substantially eliminated by the method of manufacturing the fine-perforated thin-walled grid according to the invention, which consists in that the grid-forming material has one side coated with an elastic layer, thereby achieving simultaneous hemming during punching. The layer of elastic material may be replaced by a lubricant or paint. In this way, the production operations are reduced by combining the punching and hemming operations, simplified tools can be used and the protective layer protects the material from scratches.

An exemplary embodiment of a method and a tool for producing a fine-perforated thin-walled grid with a one-sided curved aperture is shown in the attached drawings.

Giant. 1 is a cross-sectional view of a grid with single-sided lined openings without a layer of elastic material; FIG. 2 is a shear for punching and simultaneously lining the openings; FIGS.

Even with known methods of etching holes into a thin-walled grid, the active surface is irregular and has burrs on both sides.

The thin-walled grid X, used as a fixed knife for the electric eyelets of the movement, must have rounded openings on the outside. The curvature g is achieved by hemming the perimeter of the punching holes according to the invention using an elastic material 2 'applied to the molded material g.

The steel punching tool with simultaneous flashing has a shearing formed with a rounding 2 and a sharp stirrer edge.

Other tool groups such as punches g, holders g are formed in a manner known per se.

The shape of the fine openings of the thin-walled grid 1 is arbitrary. According to him, the shaping punch and the cutting die will adapt. Most economically, however, the openings are circular.

The higher effect resulting from the use of the starting material coated with an elastic layer results in a reduction in the manufacturing operations, since it facilitates the merging of the punching and hemming operations, on the one hand by simplified tools and, finally, by protecting the material from scratches.

The process for producing the fine-perforated thin-walled grid according to the invention can also be advantageously used in the manufacture of other components, for example fine-perforated thin-walled screens, both on presses and by rolling on separate rolling stands.

Claims (1)

Method for producing a fine-perforated thin-walled grid with a one-sided curved aperture, characterized in that the punching and the simultaneous edging are carried out by means of at least one-sided film of the protective material.