US1734313A - Casting apparatus - Google Patents

Description

1 Nov. 5, 1929. N w. D. VGN MALMBORG 1,734,313

*ooCEl Il CASTING APPARATUS Filed May 26, 1928 HUI Patented Nov. 5, 1929 UNITED STATES NILS W. DANIEL VON MALMBORG, F.XOKOM0, INDIANA CASTING APPARATUS Application led May 28,-

This inventionrelates to the art of producing sheet metal and more particularly to A the art of p roducing ingots. of lsuch metal which are adapted to be subsequently rolled into sheet metal and-produce a product of that character which is far more uniform tlan is at present produced by existing metho s.

The present invention is applicable particaluminum alloys, bronze, brass and other of the higher grade metals'as distinguished from ironand steel.

Itis Well known that many metals or alloys,

-and particularly those containing aluminum will, if subjected' to appreciable 'agitation/f' while being poured into molds, form a considerable amount of dross if,during the'pouring'of the molten metal,I it is exposed to the air and thus subjected to oxidation. It is also well known that aluminum oxide thus formed during the pouring of the metal has a strong tendency to remain suspended in the molten metal and is broughtto the surface only with diliiculty if at all as any stirring or agitation of the molten metal while still in the crucible or furnace or in the mold is very liable to' loosen from the walls thereof further oxide or other foreign matter asthe oxides formed during the vmelt-ing of the metal usually collect on and adhere to said walls if the metal is not stirred or agit-ated appreciably when pouring the same to produce castings.

A very important feature of the present method consists, therefore, in excluding air from the Crucible or furnace and the mold as soon as the metal has attained the desired liquid state ready for casting to produce,

primarily, ingots thereof orl other castings.

Thus, when the metal is ready to be poured, the flask or mold which is to receive the same and which is provided with one or more air vents, is secured to the crucible or about the outlet of a tiltablefurnace or thelike to produce a hermetically sealed joint between said parts. The flask or mold is then permitted to remain in place in inverted position relatively to the Crucible or furnace with its outer, and therefore, uppermost vent open toV thus allow the gases fromthe metal and its container to expel all air containedin the 192s. serial m. ascisse. i

mold and preheat 4the latter. During this short interval, those vents in the flask or mold which are apt to permit fresh air to enter the same whilethe air originally containedI therein is being expelled, are plugged suiiciently loosely to permit the plugs'to easily blow out after .the metal has been transferred to the mold in case sufficient gas pressure is generated in the mold and cru? cible or furnace to be dangerous.

As 'soon as the flask or mold so associated with thelcrucible or furnace has attained the desired Itemperature', the vent through which air hasnowbeen expelled, is plugged and the respective positions of the fiask or mold and the Crucible or furnace lreversed sov that .the latter becomes positioned to deliver themetal into the former, this vmotion being sufficiently gradual to permit smooth flow of the metal into the flask or mold without such agitation as will tend to loosen oxides or other foreign matter from the walls of the Crucible or furnace and this positioniof the latter and the v or mold in order that there may be no freezing. of metal in the outlet from the Crucible free flow of metal therefrom and reverse flow of gases displaced from the flask 'or mold by the inlowin metal as such freedom will prevent any bu bling of such ases through the metal during the pouring o the latter.

The foregoing method will be more clearly understoodv by 'reference to the accompanying drawings illustrating a conventional crucible,

.8o or furnace and the outlet from the latter is 1 preferably also made so large as vto permit of an ingot mold ofthe form required' to carry p out the said method and means for associating the mold. with thecrucible, the last-mentioned elements constituting illustrations of a suitable embodiment of my invention in so far as the latter relates to mechanism as distinguished from method or process.A In said l drawings Fig. 1 shows in central vertical section, av

Crucible associated with .a flask or mold and structure 1 composed of strips of sulliciently heavy sheet metal including a hoop 2. At diamet-rically opposite points, the latter is equipped with handles 3 and inwardly of said handles the lower ends of a pair of eye-bolts 4 are suitably secured. i

The flask or mold 5, which in the instance illustrated, is an ingot mold, is equipped with trunnions 6 for pivotally supporting the mold u-pon the arms 7 of asupporting frame or member 8, the vertical portions 9 of the arms 7 being sufficiently spaced from each other to permit the Crucible 10 and supporting basket therefor to be received therebetween.

The mouth of the mold 5 is flared as at 11 and equipped with an annular lip or flange 12 which is provided with an annular groove 13 to receive the rim of the open end or mouth of the Crucible 10, said flange being also equipped with pairs of lugs 14 bordering recesses into which the threaded ends of the bolts 4 are passed, the nuts 15 heilig then turned to draw the moldand Crucible together to provide a leak-proof joint therebetween. A suitable non-combustible packing ring may, obviously, be mounted in the, groove 18 though such packing is not illustrated.

In the bottom wall of the mold 5, I provide a vent opening 16 which is adapted to receive 'a suitable plug 17 and in the flared portion 11 of the mouth of the mold 5, I provide a small vent opening 18 which, preferably, is Closedby means of a slip-plug of-suitable material.

In use, after the metal in the Crucible is in condition for pouring,.the Crucible is disposed 'in the basket l, the mold 5 associated therewith and this assembled structure then transferred by means of a crane or the like to the supporting frame 8 as shown in Fig. 2. The mold may be preheated before association with the Crucible if so desired, and While being so associated, the small vent 18 will be closed .and vent 16 remain open. tense heat from the Crucible and gases from the latter will quicklyexpand and discharge air from the mold 5 lthrough the vent/1G which is then closed and then inverted suiliciently gradually to Cause a smooth flow of the metal'therefrom into the mold,f.the direction of rotation ofthe mold being preferably such that the metal does not pass "over the vent 18.

After transfer of the'metal to the mold', the vent 18 may be opened or the plugvtherein loosened sufficiently to relieve gas pressure in The inthe mold and Crucible, the latter remaining associated with and in inverted position until the metal in the mold has cooled sufficiently to obviate further oxidization by Contact with the air or until said-metal has become solidified. t

Obviously other types of molds may be substituted for the ingot mold shown.

The invention may be applied to sand molds provided that. preheating thereof is not carried to the point at which the superficial sand is loosened from the body thereof and thus becomes admixed with the metal.

Obviously in the embodiment shown, the Crucible will primarily maintain the mold in inverted position by gravity and, after inversion of the mold, thelatter will maintain the Crucible in inverted position by gravity. y

The invention is intended and best adapted for the production of ',ingots that are free .from dross, oxidized particlesor otherforeign matter so that they are adapted tov produce sheet me al of absolutely smooth surface and uniform texture or; in other words, sheet metal which is free otaws or imperfections of any. kind.

l claim as my invention: d

Apparatus for Vproducing metal castings which comprises a moldfhaving a mouth poltion, means for engaging bolts with the mouth portion of said mold, means at the said mouth f portion for receiving the rim ofthe moitth-` of a crucible for elifecting a hermetically sealed connection between. saidl mold and Isaid I'Crucible, air vents at opposite ends ofsaid mold,

l a pan' of trunnions. thereon adjacent the mouth portion thereof,ga, supporting frame --equipped with bearing formations to receive.

said trunnions, sa'idfmold being rotatable i said bearing formations to inverted position, a Crucible receiving and supportingstrueture having manually engageable members for transportii'ig the same, bolts pivotally se- Cured to said-members and adaptedto en gage the irst-ineiitioned means to tirmly associate the mold with a Crucible mounted in said structure, said Iair vents being sealable to permit inversiontntl said Crucible after association with the inverted mold to etfeetl transfer of the contents of the Crucible tothe mold. v

-N. W. DANIEL. voN MALMBORG.

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