US1885039A - Casting afpabatus and method - Google Patents

Description

0d' 25, 1932 J. scHMELLER, SR

CASTING' APPARATUS AND METHOD Filed Jan. 27, 1932 2 sheets-sheet 1 Trop/vers Oct. 25, 1932. J. scHMELLER, sR

CASTING APPARATUS AND METHOD 2 sheets-Sheet 2 Filed Jan. 27, 1932 Patented Oct. 25, 1 932 UNITED j STATES JOHN soHMLLEii, sa., oF LAKEWOOD, oHIo CASTING APPARATUS AND METHOD Applicationfled ll'aniiary?, 1,932. Serial No.v589,068.

This invention as indicated relates to a casting apparatus and method. More particularly it relates to the production of castx ings in permanentor semipermanent molds, L Iv and especially with metals having a low meltinggpoint and high crystallization shrinkage.

Heretofore it has been the practice in casting various objects, particularly those having thm walls, from metals having a low metal point and high crystallization shrinkage, to

adopt either the methodv f supplying adjacent oney edge of the. ca lng a considerable body of molten metal serving as a reservoir to be drawnupon by the metal within the casting cavity 1n the course of its solidifica'- tion and to supply Athe e'xtra metal needed through shrinking, such shrinking being caused 'to take -eeot initially at a' point remote from the -position of such excess supply of molten-metah'as is clearly described in the patent to Norton, No. 1,296,595, or the easting of a thin-walled section has been carried out by' supplying' to the base of the mold through a gate communicating .with the periphery thereof substantially throughout its entire extent, practically all of the metal `for the entire casting, such metal /lowing in a wide substantially continuous web through a' f circumferential gatesupplierh from a pe` ripheral runner and thence'proceeding rapid- -ly toward the upper portion offthe casting, thel entire casting being thus supplied from the base to provide a lsmooth surface finish above the periphery of the base, the entire mass of the casting then solidifying substantially at'one time, as isset forth i to F'ahlman, No. 1,770,386. y y ,v

' The present invention has in'view` the production of thin-walled` castings whereinthe metal. supply for 'the bodyportion thereof is not derived lsolely from ingatesiadacent the i peripheral lportions of Athe base, nor is supplied in successive horizontal layers from a f large, `reservoir of molten metal, so that 'shrinkage losses maybe made up vby drawing upon such reservoir of metalin the courseof" l f progggreis'sive solidification ofv the article,y butv y. is carried out by'supplying the metal to the j casting cavity at 'a plurality of points'jsimulLj taneously and 'admitting the metal y,to the n the patent casting cavity through gates of narrow width having the eHect of fiowing such metal into the interior of the cavity as a smooth nonturbulent stream, and diverting oxides and impurities from such gates through the angu-, 55 larity of the passageways leading thereto. It also has in view the provision of a', method of manufacturing castings from aluminum and aluminumalloys and the like, wherein the casting cavity is supplied through gates of 60 unsual thinness', which serve substantially as valves between the molten lmetal supply and the metal admitted to the casting cavity, such gates having so littleA mass that the metal therein freezes substantially instantaneously 05 upon 'the cessation of flow of -inolten metal therethrough', and because of the slight mass y of the gates has no appreciable eil'ect in causing draws which would distort or affect the even contour of the castingor permit interference therewith through the excess off' metal in the molten metal supplyon the opposite 'Y side of such gates. Thus, after the closing of the gates through the freezingof the same, themetal within'the casting cavity beneath 75 the level of such gates will begin to solidify and, having so little mass of metal to draw upon in the gate, will be 4unaffected by the gate and will shrink uniformly throughout such portion of the molding cavity because ofthere being no body of molten metal ad jacent to such freezing mass which could be drawn upon to supply Vthe shrinkage losses. The shrinkage undergone by a casting in the manner stated will thusbe uniform throughout and any diii'erence in size of the product will be adequately taken care ofthrough l the allowance for fsuch shrinkage in the orig? ,ipal design of the molds'. ,In addition to facilitating the production' 9 'ofjcastings -through the use `of permanentllor semi-permanent m'oldsfthe` usev of gatshof `extreme .thinne'ssprovides for the. eeonomyif; c al removal of the waste material from the y casting proper ,after` thesame is taken jfrom f thed'nold. It has beenfundithat gatles hav-fv ing a thinness ofapproximatelylf of'an yinch when the objects are' kI, ,1i1r1'edf elummimyer. a aluminum alloys are"` readily' 'frangible 'and by sharply tapping the. mass of runners 'and 10 sprues about the margins of the 4casting, the same will be freed at vonce from the body of `the casting through the fracturing of the gates close to the margins of the casting. This obviates the necessity of any sawing operations on the casting and in ycases where trimmed edges "are required, permits the immediate positioning of the casting in an automatic lathe .for such finishing operations as are required.

The invention permits the direct feeding of metal through thin-walled sections ,such as the wing members of castings for agitators for washing machines without in any way interfering with the smooth contour of the finished article, even though in current practice it has been 'considered improper to supply metal to a casting through such thin,- walled extensions up/on the theory that the flow of hot metal over such walls would heat the same to too ,great an extent and cause uneven cooling together with all of the iinperfections and irregularities which are consequent thereon. y' Thus, with the method and apparatus herein set forth, it is possible to rapidly supply metal to a casting cavity through va large number of gates distributed at a wide variety of points about a` casting and it is also possible to feed directly into a rthin-walled section such as a fin or wing of an agitator for washing machines without in any way causing any imperfections in the casting either as to the body of such casting or as to such thin-walled extensions or wing portions thereof.

In addition to the advantages pointed out above, there are many other advantages which are to be found in the invention herein 'set forth as will appearin the course of the following description.

To the accomplishment of the foregoing and related ends, said invention, then, consists of the means and steps hereinafter fully described and particularly pointed out in the claims. The annexed drawings and the following description set forth inV detail certain structures embodying such invention, and the method of making the same, such disclosed means and method constituting, however, ut. several ofvarious applications of the ypr nciple of my invention. i i

In said annexed drawings Figure 1 is a vertical sectional view of the 'apparatus taken along the 'line v1--l, shown in Figure 2, looking in the direction of the arrows; 1

` i f Figure 21s a top plan view, partly in sge'ction, taken along the line 2-2, shown yin Figu re 1, looking in the direction of the arrows;

Figure 3 is a(side`elevation of a casting formed in the 'apparatus illustratedin Figures 1 and 2;

Figure llis a top plan-view,upartly inseetlon, taken along the line44, shown'in Fig-' urel 3,`looking`in the direction of the arrows;

looking in the direction of the arrows;

`lng 'a series ofl legs and cross members, said 4 resaca@ l Figure 5 is a top plan view, partly in sect1on, of the casting shown in Figure 3, taken along the line 5-5, shown in Figure 3,;

Figure 6 is a horizontal sectional view taken through the stem portion of thecasting adjacent the plane indicated by the line 5-5, shown in Figure 3, and showing the details of the vertical gate;

Figure 7 is a greatly enlarged sectional `View of the gate and adjacent structure shown in Figure 6;

Figure Sis a view similar to Figure 1, illustrating a modified form of casting apparatus, the section being taken along the line 8 8, shown in Figure `9, looking in the direction of the arrows;

Figure 9 is a plan view, partly in section,

, taken along the line 9 9, shown in Figure 8,

looking in the direction of the arrows; f

vFigure r10 is a side elevation of a casting formed in theapparatus shown invFigures 8 and 9; l f

Figure 11 is -a sectional p-lan yview taken along the line 11-11, shown in Figure 10,

ofthe casting cavity shown in Figure 8, l

but showing a modified form of vertical sprue and passageways Yassociated therewith.

As is clearly shown in Figures 1 and 2 of. the drawings, the apparatus .comprises a base 1 in the form of a heavy annular metal mem- 1 ber supported upon a frame 2 preferably havibase havlng a central opening preferably of circular outlineA through whichk a movable coresection 3 is engaged, said core section being held against rotation by a key 3a engaging in a keywayb, and having adjacent its lower edge a projecting flange 4 adapted to limit the upward motion thereof and having an upper surface presenting a substantially flat area 5 merging with a taperedstem section 6. The core-is preferably supported il'pon a standard 7 screw-threadedly engaged ytherewith andformed adjacent its lower end' with a rack 8 adapted to be engaged'bya pinion V9 thesha'ft lof which whenoperated by a ,handle bar 10wil1 recipocate'the core sec\ tion, drawing' the same downwardly into the base upon the completion of the casting.

Qn the, upper face ofthe base member a lplurality :of pivoted moldvsections is provided each mold sectionhaving al body por'- l tion adapted to overliethe'mfar 'ns of the y base member and tle adjacent, ore surface and having side platesadapted when in'op., y7

erative position to meet corresponding side plates on companion mold sections. .f The apparatus illustrated shows three movable mold sections, 11, 12, 13, each centrally 'supportedmpon a hingeinember 14 and adapted to be moved outwardly from its operative casting position toan inclined posi-f tion with referencev to the base to a distance s'uflicient to permit the free removal ofthe finished casting. A boss adjacent the lower n handle ,16 may be secured, such handle being preferably of a lengtlrsuicient to serve as a the body ,portion of .the article referredto, so j support or prop for its mold section when in open position,` The/inner face of each mov'- able moldsection is recessed adjacent the core surfacev to provide a casting cavity for the body portion-of the article to be formed, and blocks bringsaid sections into accurate registry. ,s i

In the apparatusillustrated, anagiitator for a washing machine is indicated as the product and such articles have 'a series of wings, in this instance, .three radially spaced wing members 17, 18', 19, being shown, and the adjacent faces of the movable 'mold section are each lrecessed to`provide a casting cavity continuous with the casting lcavity for that integral wings may be formed when 4metal is supplied to such mold in its operative l position: i

The core member, .as heretofore stated, is formed with an upwardly extending stem section which may be' formed of metal throughout or, as shown in Figures 1 and 2 of the drawings, may be of metal as to itslower section and with a composition core 21 for.

ca ,vertical gate, 37, at an intermediate or- 'the upper section'of the stem. Inforder to satisfactorily position the composition core above the permanent stem section of the core, Ithe latter i s for1ned with a smallsquared Yextension 22-'on -its upper surface over which the composition `core maybe engaged and held against radial displacement. The c m: position core preferably is formed wit a supportlng wire 23 embedded centrally therein and projecting above the same and 'adajit- Y ed to be supported at its'upper, end 24 means of the frictional clamping/action of the vupper. beveled portion 125. of the assembledd mold sections immediately above lthe stem. A riser cavity I3 is formed immediately above. the composi ion core, and the supporting wire extends therethrough.

In order to supplymetal to the casting cavity above de'scr'ibed,.the meeting faces along e two of the parting'lines of the mold sections are recessed to provide 'a vertical spru cavity 26 whichA preferably extends downwardly and outwardly for convenience-of arrange.

"lower vertical edge o 'spaced wingextensions merge, sad wing'exment and economy of space, as shown in Figlire l, the lower end being somewhat reduced `in Width and outwardly offset from the main body portion thereof and entering-n arc- .shaped runner cavity .27 formed in the adjacent faces in the base and movable mold sections and provided at` spaced intervals with thin horizontal gates 28, preferably about gli of an inc/h in thickness, feeding into the adjacent portion of the base ofthe casting cavity.l SaidJ meeting faces of the respective for the adjacent Wing section, such runner at its lower end merging with the. peripheral vmovable molds are also each recessed to prorunner cavity 27 and having preferably one V`or more cross-feeder passageways 31, 32,

above the same,in the present casev two being i lndicated, one 3 1 at `a point opposite the angle of the wing and .another 32 approximately midway of the puper portion ofthe stem por- 1 tion of they casting cavity. The runner referred to may also extend upwardly a slight distance beyond the top' of the wing section in the formof a riser; j

,In order to supply metal fromv the wing feeder runner to the adjacent wing,' vertical gates 33, 34, of small thickness, preferably of about 12- of an inchmay be provided, the

jformed adjacent the the. wing cavity and adjacent the vertical portion of the upper Wing section of the casting cavity. In order to supply metal tothe wing 19, formed' at gates preferablyy being the parting plane bf the mold faces not rev cessedfor a pour-sprue,-an extension, 35, is provided |on one of the adjacent runners which' 1s opposite -such lparting plane and communicates at`such po1nt\,with a short vertical riser, 36,of a height substantially equal to that of the adjacent wing and formed with i tion-communicating'with .said wing. aid

gate'37 is also made relatively thin, being preferably not over g1g ofan inch in thickness.

The casting formed inthetfapparatus just desdribed, together with its'associated sprlie's and runners, is illustrated inFigures 4 to 6 inclusive, wherein the body portion, 41,. of

the casting is shown as an inverted trumpet stem Section', 42, with which three equally.

tensions each having a lower'portion, 43, -exshaped portion having an elongated cent-ral tending substantiallyjto the periphery of ther i `body section and of relatively smalll height" e and'having an elongated tapered upper portion, 44, merging with the upper sec-tion of .the stem from a point approximately m'dway .I

of the lowerportion ofthewing. f The :hprizontalrunners, 45, as indicated, are pesi-l -v rac tial portion of the mold.

with an extension,-46, for carrying metal to a point opposite the third parting plane, at

which point a vertical riser 47 is provided spaced slightly outwardly of the'margin of the adjacent wing section with which it coinmunicates by means of a narrow gate portion 48, the riser extending somewhat above the upper end of the gate. The riser may be carried upwardly spaced from 4the margin of the adjacent wing if the size and character of the casting so requires.

As is clearly shown in Figures 4 and 5, the horizontal gates from the horizontal runners are provided adjacent the', ends of 'such runners but slightly spaced therefrom with narrow gate sections, such gates preferably being of about gli of an inch in height and eX- tending in the form shown only a small portion of the total extent of the circumferen- The form of mold just described is intended to produce an agitator'for a washing inachine wherein three wings equally spaced about the upper surface aie provided, as has heretofore been stated. l

In/the form of Aconstrictfon illustrated in Figures 8 to 13 inclusive, an agitator casting of somewhat differentform is shown, such casting having a substantially yrectangular Outline and being formed with four wings of less height and greater width than the agitator castiiig i'irst described. f

The supporting and operative parts of the structure aie Ysubstantially the same as those shown in Figures 1 and 2, and the same refI erence characters have been. applied thereto, in so far as they relate to the identical structure. The movable mold sections, 51, 52, 53, 54, in theV modified form of construction, are

Y four in' number and the core portion A55K off `thedeviceis a permanent metal core throughout, no composition entensio'n being employed as in the construction heretofore describedf The core vmember held against rotation by akey 55a engagingin a, keyway 555, and on A-its'upper surface isl provided with a marginal area 56.1ying-substantially in a hori vzontal plane and adjacent its central portion is curved upwardly toward a stem section 57 tapering slightly in any upward direction. The stem section is a solid cylindrical member having a body portion tapering slightly 'in an upward-direction as stated,` and is specially shaped adjacent its upper end -58 to form a tor. yThe stem section f-the core is secured tothe base section of. the core through the seating of the base of the stem section within i gea lower portion ofthe stem in or'derpt form Vanannular recessfonthe upper sur-face of the boulder and a, rectangular socket'- 'within the stem of the casting to provide suitable driving engagement for the agita-- insane@ combined core members to form adepending flange on the under side of the agitator casting in alignment with the stein section thererlhe mold is supplied with four movable sections supported on the base by suitable hinge members 63 which sections are each provided with recesses on their inner faces adjacent to the core members to form the body portion of the agitator casting, and are provided on each of their meeting faces 'along the parting lines of said respective sections with recesses to form the wing porl tions 64 of the lagitator casting. T he vertical feeding sprues 65 are formed in the parting planes intermediate the flanges on two of the movable mold sections on one side of the apparatus, and likerecesses in the directly opposite pain of mold sections along the parting plane in alignment with the Afirst mentioned parting plane. The two parting planes between the respective mold sections at right angles with the parting planes just referred to `are not provided withpassageways for feeding sprues for th casting here illustrated inasmuch as adequate metal canY be supplied to said`` casting without additional feeding sprues andthe labor of fillingl and operating Ithe mold is considerably reduced by reducing thefnumber of sprues and associated passageways. At the base of the feeding sprues lateral runners 66 of V shaped formation are provided at diagonallyopposite corners of the casting cavity, such runners being formed by recesses provided partially in the base of the apparatus and partially in the adjacent under faces of the movable mold sections. The

V-'shaped sprues are of considerable width' and the vertical feeder sprues 65 communicate therewith adjacent the outer edges thereof. A runner 67, spaced slightly from. the outer marginv of each adjacent wing cavity feeding between the mold faces in which the feeder sprues', are located, is provided, and extends from the inner edge of the V-shaped runner' in, an Iinwardly'. curved direction, the upper endA thereof 68 'extending beyond Vthe ppsition of the upper edge of the wing to provide a riser cavity at suchv point. A thin gate 69 preferably of not over LZ of an inch in width connects the runner last referred to to the upwardly extending margin of the wing-,cavit A cross/feeder connection 71 is; providedl between thefeeder sprue and the upwardly extending runner at a point slightly below,

the lower end of 'the gate just referred to..

The V-shaped runners communicate with tral position intermediate the wings. A riser cavity 7 3 is provided immediately` above the top of the stem section of the core to receive excessive metal rising through the castingv cavity as the filling of pletion.

j A still further modifiedfform of construction is illustrated in Figure 14, wherein the feeder sprue 81 for the mold cavity in place the mold nears comof connecting with they V-shaped runner B2' at its outer edge and having a riser or runner extending upwardly from the inner edge 'of such V-shaped runner extends directly downwardly into the central portionv ofr the V-shaped runner', `and is connected with the adjacent casting cavity for the wing by means of two gates, one 83 entering the vertical end portion of the wing directly from the lower portion of the vertical feeder sprue, and the other I84 entering -thecurved intermediate portionof the upper edge of the Wing through a riser passageway 85 and connected with the feeder sprue at a point slightly above the top of the outer vertical edge of the wing. Each of the gates shown in Figure 14 is formed exactly similarly to the gates preferably used throughout the apparatus which as stated in a thin casting-of the type described are preferably made of 31E of an inch in thickness so as to present a very small mass relatively to the adjacent metal in the wing cavity on one side when the mold is in use and the molten metal in the adjacent passageways to which reference has been made. 1

The invention as has already been stated includes the supplying of metalto the casting cavity from a plurality of sources simultaneously and preferably also includes in each instance the supplying of such metal through gates of such narrow width as to serve after the manner of shut-ofil valves to separate the metal 'which has filled the casting cavity immediately adjacent such gates from the supply of molten metalon the opposite sideof said gates when the adjacent accruing through the control of shrinkage 'y `means of the thin gates are not the only.. ad-

portion of the casting cavity has been filled with metal and the flow nthrough suchlgates has substantially stopped. When this action occurs, as will bevery cleanly evident ,from

"Figure 7, the gate 34 intermediate the adja' cent margin of the casting 18 andthe adjacent edge of the passageway 2 9 full of molten metal tends .Lto solidify as soon as the temperature drops through the cessation of metal flow through Ysuch thin gate. Because of i the small mass of the gate there is substantially no appreciable interchange of metal.

between the gate and the casting due to crystallization shrinkage at the other edge of' the gate; the molten metal at the other side ofthe gate is effectively prevented from passing through the gate into the .casting cavity ,to supply further-hot inetal during shrinkage process. i

The action just described obviously takes place at each of the gates throughout the ap- Y paratus and the method forming a part of.-

this invention includes the steps of supplying molten metal through a plurality of passageways` to the casting cavity through a plurality of thin gates each of which gatesl is adapted to automatically freeze and effectively seal the casting cavity from interchange of metalL with theadjacent molten Imetal supply in the adjacent passageways,

shrinkage of the casting takesplace uniform- 'ly over its entire extent without being sub-V ject to draws or the introduction of strains because of the nearness of molten metal to a mass undergoing shrinkage. In this manner a casting can be produced by feeding the same at a large number ofpoints, and even feeding thin walled sections such as the Wings of agitator sections directly from a mass of moltenmetal andfree of any injurious effects either as to quality or appearance because of a fiow of metal over the walls' of the castingcavity preliminary to the final filling of such cavity with the metal which is to remain therein.

The size of the gate obviously must bear a certain relation to the adjacent masses of metal in the'casting cavity and in the feeder passageways so as to bring about the valve action or stopping of-the gate at the desired time to `produce the results referred to. lVhere the casting itself is a thin walled member of from 1/8 tos-5g of an inch in thickness, the thickness of the gate should preferably be not more than 3l; of an inch, and it has been found that gates of still lessthickness have worked satisfactorily in connection with vantages which arise through their use, and

the invention includes the use'of thin gates irrespective of this function originally stated,

inasmuch as thin Vgates are readily frangible,

at least while still hot immediately after re-1 moval from the mold. The provision of such thin gates brings about a large savinggin theY cost of finishing castings. j j

Whenfcastings have gates of appreciable thickness it is usually necessary to separate the same from the finished mold by means of a sawin or grinding operation preliminary to any urther nishing of the casting, and

this involves considerable delay and expense in connection with the handling of the casting after it is fabricated in the mold.

@ther .modes of applying the principle of.

` casting cavity, restricting its flow adjacent ythe bottom of the casting cavity, and directing it into the casting cavity 1n the form of a thin web, which comprises such a small mass of metal that when the casting cavity has been filled to substantially the level of said web and metal flow therethrough has stopped, it will solidify in advance of the metal in the casting cavity and form a seal between said metal and the molten metal supplyadjacent the casting cavity. o l

2. The process of casting articles from metal having a low melting point andl high crystallization shrinkage, comprising intro- 'ducing molten metal into-the casting cavity by pouringV the metal downwardly un der the action of gravity toward the casting cavity and in spaced relation thereto and directing the flow laterally andv upwardly and directing the upwardly flowing metal into the casting .cavity in the' form of an upwardly extending thin web which comprises such a small mass of metal that when the casting cavity has been filled to substantially the level of said web and metal How therethrough has stopped, it will solidify in advance of the metal, in the casting cavity and form a seal between said metal and the molten metal supy ply adjacent the casting cavity.

3. rlhe process of casting articles Afrom metal having a low melting point and high crystallization shrinkage, comprising introducing molten metal into the casting cavity by pouring the metal downwardly under the action of gravitytoward the casting cavity and in spaced relation thereto and directing the flowlaterallyand upwardly at a plurality of circumferentially spaced points and directing the upwardly flowing metal into the casting cavity in the form of upwardly extending thin webs, each of which comprises such asmall massl of metal that when the casting cavity has been filled' to substantially the level of said web and metal How therethrough has stopped, it will solidify in ad! vance ofthe metal in the casting cavity and neeaoae form a seal between said metal and the molten metal supply adjacent the casting cavity.

'4. The process of casting articles from metal having a low melting point and high crystallization shrinkage, comprising introducing molten metal into the casting cavity by pouring the metal downwardly under the action 'of gravity toward the casting cavity and in spaced relation thereto and directing the flow laterally and then upwardly and die recting the laterally flowing metal and also the upwardly flowing metal into the casting cavity in the form of the plurality of thin webs, each of which comprises such a small mass of metal that when the casting cavity has been filled to substantially the level of said web and metal flow therethrough has stopped, it will solidify in advance of the metal in the casting cavity and form a seal between said metal and the molten metal supply adjacent the casting cavity. A

5. rllhe process of casting metal and alloys comprising introducing the moltenmetal into the casting cavity by pouring the metal downward under the action of gravity toward the casting cavity, restricting its How adjacent the bottom of the casting cavity, and directing it into the casting cavity in the form of a web extending upwardly from the lower part of the casting cavity which comprises such a small mass of metalthat when the casting cavity has been filled to substantially the level of said web and metal tlow therethrough at said level progressively has stopped, it will solidify progressively in advance ofthe metal in the casting cavity and form a seal between said metal and the molten metalfsupply adjacent the casting cavity.

. 6. The process of casting metals and alloys comprising introducing the molten metal into the casting cavity by pouring the metal downward under the action of gravity toward the casting cavity, restrictingr its flow and directing a portion of it to flow laterally adjacent to and along the periphery of the bottom of the casting cavity and another pore tion upward and adjacent to the casting cavity, directing the laterally flowing metal into the casting cavity in the form of a thin horizontal web and directing the upward iowing metal into the casting cavity in the form of a substantially thin web, the amount of metal in each one of the thin webs being so small that when the casting cavity has been filled .to substantially the level of each respective web and the metal flow through such respective web-has stopped, said webs will solidify I in advance of the metal'in the casting cavity and form a seal between it and the molten metal supply of said web adjacent the casting cavity.

7. rlhe process of casting metals and alloys comprising introducing the molten metal into the casting cavity by pouring the metal downward under the action of gravity toand in opposite directions adjacent to. and

^ taneouslj directing ward the casting cavity, restricting its flow and directing a portion of it to flow laterally along the periphery of the bottom of the` casting cavity and another portion upward and adjacent to the casting cavity, simulthe laterally ilowin metal into the casting cavity inthe form o aplurality of thin horizontal webs, and simultaneously andprogressively directing the upward flowing metal into the casting cavity in the form of a series of successlve thin vertical webs, VA'the amount of metal in each one of the thin webs being so small that when the casting cavity has been filled to substantially the levelrof each respective web, and the metal flow through said respective web has` stopped, the said webs 'will solidify infadvance ofthe metal in the casting-cavity (2O/and form a seal between it and the molten metal supply of said web adjacent the casting cavity. v l Y 8. The process of casting metals and alloys comprising introducing the molten metal into the casting cavity by pouring the metal downwardunder vthe action of vgravity toward the casting cavity, restricting its flow and directing it to ilow laterally and thence upward in spaced relation to the casting cavity and directing the upward flowing metal into the casting cavity in the form of a -thin web which comprises such a small mass of metal that when the casting cavity has been filled to substantially the level of said web and metal ow therethrough at said level progressively has stopped, it will solidify progressively in advance of the metal in the casting cavity and form a seal between it and the molten metal supply adjacent the casting cavity.

9. The process of casting thin-walled articles havinga'tapered body portion and wings integrally formed therewith from metal having a low` meltingpoint and high 'crystallization shrinkage, comprising introducing molten metal into the casting cavity by pouring the metal downward under the action of gravity toward the casting cavity, restricting its flow and directing a portion of it to flow laterally and in opposite directions adjacent to andalong the periphery of the bottom of the casting cavity and thence upward in spaced relation to the casting cavity opposite eacli `respective wing, and simultaneouslyl directing the laterally flowing metal into the casting cavity in the form of a plurality of thin horizontal webs, and directing the upward flowing metal into the casting cavity at said wings in the form of a thin web which comprises such a small mass of metal thatI when the casting cavity has been filled'to substantially the level of each respective webfand metal flow therethrough at said f-level progressively has stopped, it willl solidify progressively in.'

advance of the metal in the casting cavity and form a seal between it and the moltenmetal supply adjacent the casting cavity.

10. The processv of casting thin-walled aiticles having a tapered body portion and I wings integrally formed therewith from metal having a low melting point and. highy crystallization shrinkage, comprising introducing molten metal into the casting cavity by, pouring the metal downward under the action of gravity toward the casting cavity, restricting its flow, and directing a portion of it to flow laterally and in opposite directions adjacent to and along the periphery ofthe bottom of the casting cavity and thence upward in spacedf relation to thex casting cavity opposite each respective wing and simultaneously directing the laterally flowing ymetal into the casting cavity in theform of a plurality of thin horizontal webs and simultaneously v and progressively directing` the upwardv iiowing metal into the wing and adjacent basep ortion ofthe casting cavity in the form o a plurality of series of successive thin webs, the amount of metal in each' one of the webs being so smallthat when the casting'cavity has been filled to substantially the level 'of` each'respective web, and

the metal flow .through said respective webl has stopped, the said webs `will solidify in advance of the metal in the casting cavity andform a seal between it'and the molten metal supply of said Webadjacent the casting cavity.

l1. A mold comprising a plurality of sections having a casting cavity, a sprue, and a narrow gate having substantially flat parallel Walls connecting the sprue with the bottom of the casting cavity, said gate .being so narrowthat the molten metal therein, when the castingl cavity has been filled to substansol tially the level of the; man of Said gate and' the/metal flow therethrough has stopped, will solidify in advance of that in the casting cavity and form'a seal between the metal in the casting cavity and the sprue.V

12. A mold comprising a plurality of. sections having a casting cavity, a plurality of sprues, and al plurality4 of narrow gates each having a pair of closely spaced walls connecting each respective sprue at spaced points llO with the castingcavity, said gates each beingso narrow that the molten metal therein, l

when the casting cavity has been filled to substantially the level of themetal ofsaid gates, will solidify in advance of that in the casting cavity and for-m a seal kbetween the metal inthe casting cavity and the respective sprues.

18. A mold comprising a plurality of sections having a casting cavity, a sprue, afrunner adjacent to the bottom of the castingY cavity and communicating 'with the sprue, anupright feeder between the casting cavity and the sprue and communicating directly with the runner, a series of narrow horizontal gates each having a pair of closely spaced i walls on both sides of the upright feeder and A communicating with the casting cavity and the runner, and a series of sucessive narrow vertical gates each having a pair of closely spaced walls communicating with the casting cavity and the upright feeder, said gates being so narrow that the molten metal therein,

ywhen the casting cavity has been filled to substantially the level of the metal ofsaid gates and the metal low therethroughhas stopped, will solidify in advance of that in the casting cavity and form a sealbetween the I metal in' the casting cavity and the respective sprues.

1li. A casting apparatus comprising a metal 'mold having a base, a movable core section cavities for carrying metal tof said vertical gates, said gates each y being of small 'width and substantial area whereby the metal therein will solidify in advance of the metal at either side of said gates. Q

'15. A casting apparatus comprising a metal mold having a base, a movable core section extending upwardly through the central p0rtion of said base and adapted to be withdrawn downwardly therethrough, a plurality of movable mold members supported on said base about said core section and in spaced relation thereto to provide a casting cavity, cavities provided in adjacent faces of said mold sections to form auxiliary extensions of said casting cavity, sprue cavitiesin said mold members for supplying metal at spaced resaca@ downwardly therethrough, a plurality of movable mold members supported on said base about said core section and in spaced relation thereto to provide a casting cavity, cavities provided in adjacent faces of said mold sections to form auxiliary extensions of said casting cavity, sprue cavities in said mold members for supplying metal at spaced points adjacent thecasting cavity, horizontal gates communicating with the periphery of the lower .portion 'of the casting cavity, vertical gates communicating with marginal portions of the extensions of the casting cavity, riser cavities communicating with the vertical gates, and runner cavities connecting with z said sprue and riser cavities for carrying vmetal to said horizontal and vertical gates,

said gates each being of small width and substantial area whereby the metal 'therein will solidify in advance of the metal at either `side of .said gates.

Signed by me this 22nd day of January,

Qici-iii sciiMnLiinn, sR.

points adjacent the casting cavity, horizontal gates communicatingwith the peripheryof the lower portion of the casting cavity, and

vertical gates communicating with marginaly portions of the extensions of the casting cavity, and runner cavities connecting with said' -f sprue cavities `for carrying metalto said horizontal and vertical gates, said gates each being of small width and'substa'ntial area whereby the metal Ytherein will solidify in advance of Vthe .metal at either side of ysaid gates.

16, A casting apparatus comprising a metal mold having a base, a movable core section.`

extending upwardly through the central portion ofsaid base and adapted to be withdrawn llO

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