US1505401A - Casting and in the process for its manufacture - Google Patents

Description

Aug. 19 1924. 1,505,401

E; MAYER CASTING AND IN THE PROCESS FOR ITS MANUFACTURE Filed March 14, 1922 .Z nrewfar;

iJ le ef Patented Aug. 19, 1924;.

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CASTING AND IN THE PROCESS FOR ITS MANUFACTURE.

Application filed March 1%, 1922. Serial No. 543,754,

lvlanuttacture; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to letters or figures of reference marked therein, which form a part of this specification. I

In some castings in iron or steel it is of frequent occurrence to find defects due to porous places, unequal shrinkage and accidental blow-holes, which necessitates scrapping the castings even when the latter appear good and uniform and well moulded on careful visual inspection so that it is only after being machined and being subjected to pressure tests that the castings show want of tightness.

These defects are particularly serious and objectionable in the case of certain articles such as the cylinders for motor-car, aeroplane engines, and locomotives, hydraulic piping and presses, etc.

The present invention has now for its object to obviate the above mentioned de-' fects.

This object is efiected by joining to the mass of the castings, in pouring the metal a solid plate or sheet of metal of such shape and dimensions that the walls of the castings which are strengthened or rendered tight thereby are thus composed partly of ordinary casting metal and partly of rolled or drawn sheet of metal having a higher melting point, this part of rolled sheet constituting one or more of the walls of the castings.

Owing to the temperature to which this sheet of metal is subjected during the pouring operation an intimate union takes place between the two parts of the castings.

The walls of the castings thus produced are rendered fluid-tight and are strengthened owing to the pressure of this sheet of metal.

On the other hand the presence of this rolled or drawn sheet of metal acts, during the pouring operation, chemically and phy ically upon the quality of the casting also metal that is situated in its immediate vicinity, For instance the casting metal in eontact withthe sheet of soft steel becomes decarburizedand the grain of the casting metal is thereby rendered finer so that the casting metal becomesstronger and more fluid-tight. i

I The sheets of metal are usually rolled and of flat, tubular, or dished form, or drawn in the form of tubes, and they may be covered with a suitable metal or coating. 7

For. instance,

they .may be previously tinned.

The shape of these "sheets of metal de-.

pends necessarily on the shape of the walls of the casting. Inthe application of this invention to a cylindrical article" (engine cylinder, press cylinder,'pipe, etc.) the sheet "of metal consists simply ofa tube or'of a'metal sheet bent in theform of a tube.

'lVhen the invention is applied on the contrary to walls of more complicated form, such as cylinder jackets, valve chests, etc,

the'sliape of the metalplate is usually produced by dishing or profile-shaping.

I It is to be note'd that the process, according to the invention, which has {as result the obtaining of castings having walls of mixed composition, comprising a part of cast-iron and a part ofmetal sheet, this latter being placed on one of the faces of the walls, is essentially different to the process which consists in obtaining castings having a sheet of metal placed near the middle of the'wall, this sheet serving to the strengthening of the casting.

The accompanying drawings illustrate by way of example the positioning of these metal sheets in the case of an internal combustion engine cylinder,uand in the case of a tube. v

Figure 1 is asection of an internalcombustion engine cylinder and'other elements forming the casting. I

Figure 2 is a section of a tube. V

As shown in Figure 1, the arrangement is as 'follows: i

A tubular metal sheet 1 insertedin the cylindrical portion of the engine cylinder.

A dished. metal sheet 2 inserted in the head.

A cylindrical metal sheet 3 arranged around the suction pipe. I

A metal sheet 4 arranged around the exhaust valve chest.

A cylindrical metal sheet 5 arranged around the socket for the sparking plug.

It is to be'noted that according to circumstances, according to the nature of the metal, and the quality of the castings to be produced it is optional to use plates 01- sheets or tubes of any suitable shape and material, thesenietal sheets being joined atterwards to the Walls of the casting.

In the case of Figure 2, a plate 6 is pro vided which is placed on the outer surface of the casting tube, and another plate 7 which isarranged on the inner surface of the said tube.

It is to be noted that in thecase of the pouring of castings having a complicate form as cylinder-blocks for internal combustion engines (Fig. l). or other pieces presenting variable thicknesses, the use of'metal sheets, according to the present invention, prevents the contraction of the cast iron and consequently the defects of leakage on the spots Where the variation of the thickness of said pieces is notable.

In considering, by Way of example, the spot 8, Where the outer surface of the coolin}: jacket 9 is joined to the cylinder properly so called. The founders know that by the cooling of a casting, it is specially on this spot that the defects of leakage are produced, by the formation of cracks and by obtaining cast-iron of porous constitu tion.

By the interpositionof a metal sheet according to the invention. the following advantages are specially obtained (1) The cylinder properly so called is poured as having only Wall of uniform thickness, whereby the pouring OPQIHJJCIOHQS assured to be particularly regular, that is to say, Without swells, erks and shocks.

The inconveniences of the contraction, produced by cooling on the spots as 8, where the variation of section. is a sudden one, are prevented by the fact that the overthickness is divided into two parts by the metal sheet, in such a manner that the con traction on these spots is produced. as if there were on said spots t vo distinct pieces of normal thickness.

Claims.

' l. A casting having relatively thick and relatively thin portions, in coniliiination with ietal sheets, the sheets being positioned on the surfaces of the relatively thin portions, and embedded in the casting in the relatively thick portions, so as to be enveloped by.

the casting, the changes from the surface positioning to the embedded positioning occurling at points Where there is an abrupt change of thickness in the casting.

2. A casting according to claim 1, the changes from said surface niolding,to said envelopnient by the cast metal, occurring at points Where there is an abrupt change of thickness in the casting.

In testimony whereof I aliix my signature in presence of two Witnesses.

Witnesses LEONARD LEVER, v Gnoncns VANDER HAEGHEN.

ERNEST MAYER.

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