DE423570C - Expansion of engine pistons or other hollow bodies - Google Patents

Description

GERMAN EMPIRE

ISSUED JANUARY 7, 1926

REICH PATENT OFFICE

PATENT LETTERING

CLASS 49 i GROUP 9.

(W6 ₁₅ 8 ₅ I \ 49i)

Karl Wolfram in Schalksmühle i. W. Expanding engine pistons or other hollow bodies.

Patented in the German Empire on November 11, 1924,

The invention relates to a method and

a device to expand or expand hollow or ring-shaped metal bodies,

z. B. cast iron pistons for engines, pumps, compressors and the like.

There is a method for engine pistons known in which the expansion by Filling material with a higher coefficient of expansion takes place by placing the latter in the piston is enclosed and heated with this. The .Füllmaterial should here as a result of its larger expansion widen the piston. This procedure has the drawback that enlargement is entirely subject to chance and

will not take place evenly, because the piston is not everywhere the same wall thickness to have.

In the method of the invention, the hollow bodies, with or without an enclosed filler material, are heated and inserted into a housing enclosing the same and are set in rapid rotation with this. The housing has the width that the hollow body is to be given by the expansion. The expansion takes place evenly through the rapid rotation or spinning within the enclosing housing.
The drawing shows a representation of the method and an example of an embodiment of the device used on an engine piston.

The piston α is made with small metal parts or other small but heavy components

ao parts filled out, put together with these in a glowing or hot state. Or the piston and the filling compound are heated individually and the latter is then poured into the former. To prevent the filling compound from falling out, a cover c is screwed on.

The piston is then inserted into a housing b , which is wider in diameter by as much as the piston is to be expanded or expanded. The housing b is mounted in a suitable manner and is appropriately set in rapid rotation, the filling compound exerting pressure on the piston wall due to its centrifugal force obtained as a result of the rapid rotation and driving it outwards, as a result of which the piston is enlarged in diameter will. The rotation is continued until the piston has cooled down and then retains the expanded shape. The piston is then removed from the housing, the filling compound is emptied and the former is fitted into the cylinder.

Other hollow or ring bodies are also expanded in the manner described above.

In the drawing, a housing b adapted to the piston a is shown; in this case, a different housing must be available for pistons or other bodies of different diameters or corresponding reducing jackets must be used.

Instead, however, a calibrated or adjustable housing or such can also be used Jacket come into use, in which piston, etc., different diameters are used can be.

With a sufficiently high number of revolutions of the housing with the hollow body to be expanded there is no need to fill in with filler material.

Claims (1)

Patent claim: Procedure for expanding or expanding engine pistons or others Hollow bodies and ring bodies with or without the use of heated filler material, characterized in that the same in heated state in a calibrated or adjustable, to exact internal dimensions manufactured housing can be rotated or spun quickly until it cools down.