US2411176A - Method of making metal castings - Google Patents

Description

` Nov. 19, 1946..

C. wEsSEL METHOD OF MAKING METAL .CASTINGS 6 Sheets-Sheet l Original Filed Dec. 16, 1940 Zz/e1@ Zoff @fz daag/el Nov. 19, 1946.,

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`METHOD OF MAKING METAL CASTINGS Original Filed Dec. 16, 1940 6 Sheets-Sheet 3 y ,ff/f/f/f f /0 NNW/ iwf/enza?? Nov. 19, 1946. c. wEssl-:L

METHOD 0F MAKING METAL CASTINGS 6 Sheets-Sheet 4 original Filednec. 1s, 1940 EABLY@ Nm?. m9, i946. C, WESSEL METHoD oF MAKING METAL cAsTINGs Original Filed Dec. 16, 1940 zza 17,2 170101 10@ 596 Nav. E99 w46, c. wEssfEL METHOD OF MAKING METAL CASTINGS Original Filed Dec. 16, 1940 6 Sheets-5heet 6 Patented Nov. 19, 1946 2,411,176 mamon or o inlener.. cas'rnvos.

Cari Wessei, Uhicago, assignor to Carl Wessel and Lew W. Gleminson, (Chicago, lll., trustees 4Eontilnuaticn ci' application Serial No'. 370,344,

Eiecemher lid, ldt). fllhis application Septemher 23, i942, Seriali No. 459,893

t cams. (ci. za-acti 1The present invention relates to methods oi y making metal castings.

This application is a continuation of my prior application, Serial No. 370,344, led December 16,

i940, U. S. Patent No. 2,309,608, issued January 26, i943.

Vlhile the presentmethod of making castings may be used lfor making all kinds of castings it has been illustrated in connection with a mold for making sludge or blanks which are to be drawn into metal containers.

The method according to the present invention may be briefly characterized as follows:

According to my method, any type of clean scrap or any other metal in ingot form that has heretofore been used for drawing may be used as raw material. The raw metal is rst melted in a furnace and poured from the furnace in a heavy stream into a tilting ladle so that it will contact a minimum amount of air.

Flame may be applied to the top of the liquid metal in the ladle for the purpose of excluding the oxygen and maintaining the metal and mold at a predetermined temperature. As a general rule, `no special iluxes are needed, provided,the metal was clean. x

The ladle constructed according to the present invention is lined with a suitable refractory and preferably so mounted that it may -be tilted, and

. the mold is preferably secured directly to the ladle at a discharge aperture which is located above the free surface of the molten metal.

The mold may then alsov be preheated by the application of ame to an opening in the top of the closed ladle, the flame striking the surface of the metal and being deilected upward into the mold through the discharge opening of the ladle. The discharge opening of the ladle into the mold is, of course, open at this time, and

the ladle or mold is `preferably provided with` some means for openingand closing this discharge opening.

* The next step is the mung of the iadie umn the free surface of the molten metal passes through the discharge opening into the mold, and the mold is preferably so arranged that the metal wells up into the mold from a filling opening 1ocated at the bottom of the mold, driving out the small amount of air which may be in the mold,

through the cracks between the mold parts.

-The amount of molten metal in the ladle and the amountl of tilt of the ladle is such that the mold is not only filled, but there is a head of'metal in the ladleat a higher yelevation than the metal in the mold, and when the mold is full the metal 55 a 35 mitted to run back into the ladle.

ltherein is subjected to continuous pressure ofthe head of metal in the ladle.

.as the ladlehas a large body of molten metal in ity andthe mold has a relatively small amount g of metal in it and the mold is connected to the ladle at the discharge opening thereof, the outermost part of the mold tends to cool rst and this is also true of the casting in the mold. Very soon after the mold is f11ed,or immediately lo thereafter, cooling begins and there is a gradient of temperature, the temperature decreasing from the iilling opening of the mold to its outermost parts. The casting cools from its outermost parts down toward the iilling opening, and as itcools l and shrinks additional metal is supplied from the head of metal in the ladle until the shrinkage is all taken up and the metal casting in the mold has congealed.

At this time the supply of metal to the mold is cut off at a relatively large sprue and the ladle may -be tilted back, since the discharge opening is now closed, and the metal cannot run back out of the mold. 'I'he metal does, however, run back from the closure at the discharge opening of the mold.

The4 next step comprises the cutting off of the sprue or gate immediately adjacent the surface of the casting, which produces a ilnished casting Without any sprue that must be cut oi after the castings are removed from the mold.

The mold may then be opened and the castings removed, and Iby means of the opening of the closure at the discharge opening of the ladle, :any remaining molten metal in the large sprue is per- 'I'he conduits in the mold leading to the actual cavities of the mold are then cleaned of their excess metal or sprue,and the mold may again lbe closed after removal of the castings for a recasting opera- 4,0r tion.

Slugs made according to this method are of Vsuch uniform homogeneous crystalline structure that they do not need to be preheated before they are drawn into tubes or boxes. Such tubes or boxes may be drawn from slugs made according to this method Without preheating` and Without the diiiiculties which have .been encountered in the drawing of tubes from blank slugs punched out of sheet metal. 'I'he -boxes made bythis method are practically perfect and the amount of rejections reduced to a small fraction of the percentage of rejections according to the meth- Y ods of the prior art.

The slugs made according to this method have smooth, bright surface, which may be im- I apparatus for casting by mediately subjected to polish without any machining or grinding, and as there are practically no imperfections in the slugs, there are none to be drawn out into imperfections in the tubes.

It should' also be understood that the present method of casting is not confined to the making of slugs for tubes, but may be used for making castings of all kinds.

Another object of the invention is the provision. of an improved method of making blanks fory drawing operations, by means of which the blanks may be made of homogeneous crystalline structure without the imperfections that are found in the sheet metal slugs of the prior art, and without the conditions of strain and tension that are produced in the sheet metal slugs by the operations to which they have beenl subjected.

Another object is the provision of' an improved means of -whicn castings having larger grain, softer metal. and more homogeneous characteristics may be made.

Another object of the invention is the provision of an improved method of' casting by means of which the defects of theprior art methods, such as for exampleblow holes, inclusions, faults, cracks, and other defects are practically eliminated.

Another object of the invention is the pro-I vision of an improved casting apparatus, which is adaptable to use in small plants and which is adapted to produce characteristics of a high degree ofl uniformity of crystalline structure and uniform smooth outer surface adapted to be polished.

. Other objects and advantages of the invention will be apparent from the following description and the accompanying drawings, in which similar characters of reference indicate similar parts throughoutythe several views.

Referring to the six sheets of drawings which accompany this specication,

Fig. 1 is a side elevational view of a casting apparatus constructed according to the invention;

Fig. 4 is a fragmentary sectional view on a f larger scale, taken on the plane of the line 4 4 of Fig. 2;

Fig. 5 is a fragmentary vertical sectional view, taken on the plane of the line 5--5 of Fig. 4, lookingin the direction of the arrows; i

Fig. 6 is a fragmentary vertical sectional view taken on the .plane of the line 6--6 .of Fig. 4, looking in the 'direction of the arrows Fig. 7 is a diagrammatic vertical sectional` view, taken on the plane of the line 1-1 of Fig. 3, showing the complete apparatus as it appears afterthe castings have just been completed:

Figs. 8 and 9 comprise` two fragmentary sectional views showing the condition of the casting in the mold after the mold has been lled by tilting and after the mold and ladle have been held in tilted position long enough for the metal to congeal and shrink in the mold, and to partially congeal in the conduit leading from the ladle.

Fig. 8 is a horizontal section taken on the same plane as Fig. 4;

,same planes as Figs. 8 and 9, showing the same apparatus, with the parts in the position which they assume in the manipulation of the parts of the mold to cut off the sprue at the side ofl the casting;

Figs. 12 and 13 are two views similar to Figs. 8

and 9, showing the Darts after one side of the mold has been withdrawn and the mold opened for access to the castings; y. Figs. 14 and'l5 are two views similar to Figs. 8 and 9, showing the parts of the mold after the open mold has beenemptied of its castings and 'of the sprue or excess metal remaining in the conduits leading to the cavities;

Fig. 16 is a diagrammatic view in perspective, with the parts broken away to show the structure of the mold cavities and members which form .the conduit leading to the oavities,'and which are adapted to cut oi the sprue;

L Fig. 1'7 is a view iti-perspective of one of the cast metal slugs or castings made according to the present method;

v Fig. 18 is a view in'perspective of a drawn tubular box made from the slug l1 according to the present method;

Fig. 19 is a fragmentary sectional view, taken on the plane of the line Isf-I9 of Fig. 4, looking in the direction of the arrows.

Referring to Figs. 1'7 and 18, the slug shown in Fig. 17 is merely exemplary of one of the forms of small castings that may be made according to the present invention.

It comprises a piece of metal, the shape in plan being the same as the plan shape of the box or tubular member of Fig. 18. Thus it has four plane sides 2li, and the upper and -lower plane sides 2| and the corners are preferably rounded at 22. 'Ihe opposite sides of the slug are parallel to each other and perfectly smooth and plane.

One of the characteristics of the castings made according to the present method is that the sides oi? the castings are so smooth that they may be polished without any intervening` machining or smoothing operations. v It should be understood, however, that this slug is merely exemplary of the many different forms of castings that may be made, as I have made table knives, spoons, forks, and many other small articles according to the same method.

I desire it to be understood also that aluminum is merely lone of the metals which may beI utilized according to the present method.. and that the invention is not limited in its use to non-ferrous metals, but may be employed .for practically all ferrous and non-ferrous alloys and metals.

Referring to Fig. 1B, this is the container which is formed from the blank of Fig. 17, and it is provided with a bottom 23, and the four plane sides 24, the opposite sides again being parallel to each other, and the corners being rounded at 22. The box of Fig. 18 is formed according to the usual methods of drawing such members from metal blanks, except thatin the present specic instance it is found that by means of my cast metal slugs it is 'not necessar to anneal the metal or preheat it, as it was in making the Fig. 9 is a vertical section taken on the same plane as F18. 6;

Figs. 10 and 11 are two views taken on the tubular containers from the sheet metal blanks of the priorvart. v

I desire it to be understood also that the tujbular container'of Fig. 18 is merely exemplaryof one form of receptacle or container or drawnv i metal member that may be made accordingto the present method..A The presentl methods may be ,j

anniv@ utilized fol-making all kinds oi containers, such as kitchen utensils orother articles which may be made by drawing processes.

Referring to Figs. 1 to 3 and 7, all indicates the casting apparatus in its entirety. This apparatus may have its parts further designated ascomprising the ladle 3i and the mold apparatus 32. The ladle 3i is preferably supported for pivotal movement upon a pair of bearing brackets 3,3, which may be identical in shape.

Each oi' these bearing brackets has the foot nanges 3c and the upwardly extending columns 35 suitably reinforced by reinforcing flanges 36, and at its upper end the bearing bracket hasl a horizontally extending socket 3l for receiving the be i i im: mmbel 33.

The 4bearing member 38 may be provided with vertically extending trunnions 39 at the top and bottoni.l and located in bearing apertures 40 so that the bearing 38 is mounted for pivotal movement on a vertical airis, and is self-aligning with respect to the same bearing on the other bracket lili.

The ladle 3l is preferably pivotally supported on the brackets 3b by means of a centrally located metal bearing band di, which has a laterally pro jecting trunnion l2 at each end, as shown in Figs. l and 2. The trunnions d2 are rotatably mounted in the bearings 3b, which are aligned with suitable bearing metal at d3.

The band di embraces the sheet metal housing dit of the ladle, to which it may be secured by rivets, welding, or any convenient method. The trunnions i2 are preferably located substantially midway between, the ends of the ladle, or slightly upward of the middle oi' the container so that when the ladle is empty and the mold apparatus 32 is attached, it is still held in upright position. When it is iilled with metal, the ladle tends to maintain its upright position by virtue of its own weight and the weight of the metal in the ladle. but it may be easily tilted because the apparatus is in a condition approximating 'a balance.

The ladle 3i consists of a member which has an outer sheet metal shell, such as the jacket 44, carried by trunnions d2. Inside the metal jacket 44 there may be a layer of suitable insulation, such as rock wool d5 or other temperature resistant heat insulating material.

The ladle 3i has its next inner layer 46 made of iirebrick or other suitable heat retaining and temperature resistant heat insulating material, and the rebrick may be suitably spaced from the metal shell and sides ofthe shell.

The spacer blocks 41 would also be made of the same material as the iirebrick and would transmit a minimum amount of heat through the rock wool 45 to the shell 44.

'I'he ladle has its innermost lining 48 made of suitable refractory material which is adapted to withstand the high temperatures to which this lining is subjected by the molten metal and by the application of heat with llame. asillustrated in Fig. '1.

The shape of the container chamber 49 is preferably round when viewed in plan and tapering from'the bottom toward the top, and the lower comers at 50 are preferably rounded so as to facilitate cleaning ofthe chamber 49.

At its upper end the nrebrick lining 46 is provided with a. cylindrical recess 5I for receiving a removable cover 52, which may also be made of irebrick material.

. The cover 52 lits in the cover aperture 5| and is of substantial thickness, being substantially horizontal ilange 56.

The rectangular frame 54 may project beyond the cylindrical shell 53 at the four corners of the rectangular frame member 54 and may be provided with apertures in the horizontal flange 56 foi-.receiving the elongated bolts 51, which extend to the` lower end of the metal shell 44 and there pass through the radially projecting ears 58.

The bolts 51 clamp the upper frame 54 to the shell 44 and secure the cover members 52 and 53 in place. The cover member 52 is preferably provided with a. pair of tapered apertures or conduits 58 and 68. The aperture 59 is merely for application of heat by means of the name 6I from a gas burner 62, having an adjusting member 63 for determining the amount of air which is 'fed into the nozzle e2 with the gas.

The gas burner t2 maybe secured by means of a bolt b4 to one of the vertical iianges 55 oi the rectangular frame 5i. Conduit 59 tapers upwardly andv is arranged at one side of the container dd so thatthe flame bl may be directed inwardly toward the surface b5 of the molten metal iid-and be deected upwardly into the conduit bil, which is the discharge conduit leading to the mold apparatus 82.

Conduit 3b is preferably also provided with a refractory lining ing i8 previously described. This conduit also tapers upwardly to the discharge opening leading into the mold apparatus 32.

The cover 52 is secured to the metallic cover plate 53 by means. of suitable bolts which are embedded in the rebrick cover 52 tance from the lower surface of the cover 52. The rebrick insulation of which cover 52 is made extends upwardly into an aperture 10 in the metal cover plate 53, and the refractory lining 61 extends upward into an aperture 'H in a guide plate 12 so that the conduit 60 is adequately insulated against the transmission of heat.

The metal cover plate 53 preferably supports the metallic guide plate 12, which is provided with the aperture 1I, registering with the discharge aperture 60.0f the ladle. The guide plate 12 (Fig. 6) comprises a flat metal member, which may be of substantially rectangular shape, as shown in 44 by spacer blocks 41 at the bottom Figs. 8 to 15, and provided with an upwardly pro-` jecting border 13 surrounding three sides of the ,hat surface or bed 14 of this guide plate. The innerwalls 15, 16 of this border (Fig. 14) act as guides for certain other parts, further to be described, and the border 12 may be provided with apertures for receiving the screw bolts 11, which pass through this guide plate and are threaded into the metallic cover plate 53.

The' mold apparatus 32 preferably includes an upwardly extending frame, indicated in its entirety by the numeral 80. 'I'he frame 80 consists of a pair of upwardly extending angles 8|, 82 at the side of the machine in Fig. 1, and another pair of similar bars 83, 84 at the opposite side.

These bars are bolted to the rectangular frame 54 at their lower ends, and they are joined together by auxiliary frame members 85, 86 at each side of the machine and by elongated frame members 81, 88 extending across the top of the frame (Fig. 3).

This provides a top frame which comprises the b1, similar to' the refractory lin-` at some' dis- 91, with the ribs |01 in Thusv the mold members 98, '91 are secured at 70 (Fig. 5). The space between the side walls |43 7 members 85, 88, 81, 88, supported by the columns 8| to 84. The top frame may support a guide plate 90 (Fig. 2) similar in constructionto the guide plate 12 previously described, but oppositely located.

'I'hls guide'plate also has a depending wall or border 9| which serves to guide the adjacent parts for sliding movement, but is open on one side, that is, the right side (Fig. 6). The mold may be indicated in its entirety bythe numeral Referring to Fig. 16, the main parts of the mold comprise the oppositely disposed mold members 98 and 91, each rality of cavities 98 posed members 99 and |00, duit to these cavities, and serve to sprue.

In addition to this, the mold has a pair of doors, best illustrated at |02 (Fig. 8) and other associated parts for controlling these members.

The mold members 98, 91 may be similar'in structure except that they are right hand and left hand members, as disposed in the drawings.

As a matter of fact, if the member 91 is turned end for end, it will be seen to be substantially similar to member 96. Each of these and the two oppositely diswhich form the concut oif the members and all of the main parts of the mold may be constructed of suitable metal of sumciently high melting point in relation to the metal to be used for the castings, so that it will withstand the heat without damage. For example, the present molds may be made of iron or steel, when used for aluminum finish of the mold is, therefore, very smooth, for the purpose of producing a casting of finished characteristics.

`Each of the members 96, 91 comprises a vbar of metal, having a plane face` |03, which is formed with a multiplicity of the cavities 98 complementary in shape to the slug, which is shown in Fig. 1'1. One of the slug is arranged in the plane of the surface |03 of the mold so that it will be formed by means of the plane surface |04 on the door |0| or |02.

The mold member 98 is provided with a lling aperture |05 at one side of the cavity 98, and the filling aperture preferably communicates with a transverse slot |08, which is rectangular in cross section and just as wide as the filling aperture |05 from top to bottom. Y

The slots or grooves |08 are adapted to receive the regularly vspaced transverse ribs |01, which are locatedv on the mold members 99 and |00. These ribs |01 are also rectangular in cross section and have an accurate smooth ilt in the grooves |08. They are of such length,on the member 99, for example, that they leave a `small aperture at |08, which is actually the lling aperture of the moldcavity.

In other words, the ribs |01 partially close'the aperture |05, previously mentioned. The molds 96 and 99 are viixedly secured to the framework in vertical position, parallel to each other, and spaced from each other sufiiciently so that the members 99, |00 can slide between the molds 98,

the grooves |06.

the bottom by means of brackets ||0, to the guide plate 12. At the top these mold members are similarly secured to the guide plate 90 by means of brackets 2, |3.

These metal mold members are preferably provided with heat insulation, which may take of which is provided with a plu-k slugs, and the interior.

side of the groove on the inner face. Rib forma--l positely disposed, and it larger planel faces of this the form of an insulating covering ||4, which isy The mold members 99, |00 may also be substantially similar in construction, with a few Mold member 99 may comslight differences. prise a bar of iron or steel or other suitable metal, which is provided with the rectangular horizontally extending ribs |01 at regularly spaced points on each of its opposite sides and projecting from the plane parallel surfaces |20, 2

The sides of the mold members 98, 91 also have plane surfaces at |22 and |23 for' engaging the surfaces |20 and |2|, respectively. At its inner side the member 99 is provided with a longitudinally extending substantially hemicylindrical groove |25. y

This groove has such a diameter that it leaves a, plane surface or rib formation |28, |21 at each tions |26, |21 are formed with the Plane Surfaces |29 at their inner ends, registering with what may 'be called a. filling slot |29 leading t'o the filling aperture |08 of the mold cavities 98. The mold member |00 is similar in shape to the member 99, previously described, but is opis also adapted to fit against the adjacent sides of the molds, as it has ribs |01 for sliding in the has the mold filling grooves |29, a part of which may be seen at Fig. 16. The mold members 99 and. |00 may meet at a, point between the front and back of the mold cavities.

The guide plates 12 and 90 are adapted to slidably support an additional pair of mold plates |30, I3I, one located at the top and one. at the bottom of the mold assembly. The mold plates |30, |3| may be substantially similar in structure,

except the mold plate' |3| has a tapered filling aperture |32, which registers with the refractory lined conduit 80 at the top of the ladle, while the mold plate |30 is imperforate, being located at the top of the mold. Each of these plates is of sufcient width to nt in between the side walls |35, |38, |31, |38 on the upwardly and downwardly projecting borders of the guide plates 12 88 opposite direction from the open sidevof the plates and 90.

The platesl |30, |3| may also be formed with the depending border |40.,and the upwardly 90 and 12.v

The thickness of the plates |30, |3|, seen in Fig. 5, is such that there is a clearance between these plates and the mold members 98, 91 at |42 y and |44 (Fig. 5) of the plates |30 and |3| is such that the rectangular endsof the members 99, |00

, may be iixedly secured or slidably mounted bctween these side walls |43, |44. Thus the mold '75 member |00 (Fig. 6) may be iixedly secured to grooves |08. It also' actuating these members the member |45 which pass through the plate and are threaded into the mold member.

Thus the mold 'member moves with the plates |30 and |3| at all times,` and for the purpose of is provided with a thrust plate |46, which is secured to it by screw bolts |41, and which has a socket |48. An actuating screw |49 has its end in the socket |48 and is provided with a groove |50 of circular cross section, which registers with a similar groove A circular wire |52 (Fig. 4) bent to annular shape, and located in the'grooves |50, |5|, may hold these parts together, but permitrotary motion Ibetween the screw |49 and thrust plate |46. Wire |52 may be forced in through a tangential aperture. Screw |49 (Fig. 4) extends through an internally threaded member |53 constructed like a follower, but fixedly secured to the vertically extending bars 63 and 84 by screw-bolts 54. Handle |55 permits the screw shaft to be rotated and causes the mold member |00 to move back and forthas desired, in Fig. 6. In this motion it carries with it the plates |30, |3|, which are guided by the plates 90 and 12. i l

'I'he mold member 99 is slidably mounted between the walls |43, |44 of the plates- |30, |3|, its movement being limited by the mold member |00 and by the abutment at |60. l

This mold member may be provided with a pair of rearwardly projecting lugs' 6| for engaging the cams |62 carried by cam are rotatably mounted in the and adapted to be actuated by The cams abutment for limiting the movement of the mold member 99 toward the right in Fig. 6. i

The-mold doors |0|, |02 are best illustrated in bearings |64, |65, lever 66 (Fig. 10).

' Figs. 8 to 15 and Fig. 4. The main bodies of each shafts |63, which |62 are adapted to provide a variable of these doors comprise a bar of the same metal 1 as the rest of the mold and of substantially rectangular cross section. These bars of metal t) against the plane surfaces |03 and close the cavities 96- on that side. The doors |0|, |02 are provided with upwardly and downwardly extending trunnlons |10, the trunnlons being rotatably mounted in bearings carried by the guide plates 90 and 12.

'I'he oppositely facing edges of these doors -|0|, |02 are also provided with the slots |1| (Fig."12) of rectangular cross section for permitting the sliding of the ribs |01 on the mold members 99, |00 (Fig. 16).

The metal bodies of the doors |00, |0| are preferably provided with a layer of insulation at |12, covered by a metal shell |13 secured to the doors |0|, |02 by screw bolts, and the shell |13 is curved around the trunnlons |10 so as to permit suitable clearance between the doors and the mold members 96, 91, so the doors may open'to the position shown in Fig. 12 from that of Fig. 8 for removal of the castings.

The operation of the mold is illustrated in Figs. 'l to 15. The mold is secured in Fig. '1 in vertical position on the topof the ladle 3|. 'Ihis is satisfactory in the present case because the filling conduits are so vances in a solid stream without any splashing.

of the molds 96, 91

large that the metal ad- In other embodiments of the invention, where Y v-the cams |62,

10 is tilted the free surface 65 of the metal 66 in the ladle would well up into the mold.

when the casting operation is to be begun", the

the cavities filling by the gradual rising of the free surface of the metal in these 'lcavities'without any splashing or exposure to air other than that which is in the cavities.

The moldV cover plates or doors |0|, |02 fit quite closely against the molds 96 and 91, but the air may still escape through the cracks, although there is substantially no nn formed on the castings, due tothe close iit of the parts of the mold. 'I'he ladle is'then tilted .back to the vertical position shown in Fig. 7, and due to the cooling of the metal themetal in the mold and conduits looks as it is shown in Fig. 7.

The manipulation of the mold is then as follows: Referring toFigs. 8 and 9, it will be observed that the parts are shown here in the position of Fig. 7. The cavities are all nlled and partially congealed, 'and a small amount of metal is congealed in the conduitl |25, but the molten metal at the center runs back into the ladle.

The next step is the turning of the stop `cam shaft |63 by means of lever of Fig. 8 to that of Fig. 10, establishing a1 dinerf ent stop position for the member 99'. The screw of the member |00 against it. The turning of the l screwis continued until members 99 and |00 are stopped by the engagement of the lugs |6| with as shown in Fig. 10. This motion has caused the member |00 to shear olif the sprue at a point immediately adjacent the side of the casting, by means of the cutting edge of the ribs |01 in the grooves |06. In this action the conduit |25 in the mold members 99 and |00 has also been placed slightly off registry with the conduit 60 in the ladle, as seen in Fig. 11.,

The next step is the withdrawal of the member |00 by means of the screw shaft 49 and handle |55, bringing the parts in thel position of Figs. 10 and 11 to that of Figs. 12, and 13. 'Ihis movement of the mold member .|00 draws with itthe lower plate 3| and cuts `off the vertically extending sprue at the aperture |32 (Fig. 13).

In addition, the member |00 is wholly withdrawn from between the doors |0|, |02, so there willbe no longer any .bindingbetween the adiacent sides of thegdoors, and the member |00, and the doors may then be pivotally opened from the position of Fig. 10 to that `of Fig. 12.

The castings may then be removed from the cavities, and the hollow sprue |15 (Fig. 12) may be removed ,from the groove I|25 in the member 99, where it stands, and the parts are then in the position as shown in Figs. 14 and 15,-when the cam |62 may be turned back to the position oi' Fig. 8 and lthe mold closed again to the position of Fig. 8, to beused again. l

My method lof making castings is-as-follows:

|66 from the position` low tube into the ladle 3l.

Q by means ofthe mechanism of the molds ing the parts from the position ofk Figs.

y The ladle 3l and the mold are preheated byv means of the' gas burner 62 until they have y, reached approximately the temperature at which been used for drawing and extruding. and the melting may bev done ina furnace where the vmetal may be cleaned and skinned offv so that it will be clean in the ladle. 1

It is poured in the ladle in such manner as to reduce the contact between the air and metal to a minimum, such as the pouring in a large stream.'

Thereafter, the preheating of the mold may be l12' removed from the mold. This is done while the parts are in the position of Figs. 12 and 13.

Thereafter the castings are taken out immediately, the Iparts being again placed inthe posi# tion of Figs. 14 and 15 within a very short time after the ladle and mold have been tilted back to verticalposition.

At this time the castings are still very hot. and

such shrlnkage'as takes place during the congelation of any part of the casting is taken -up by the supply of additional metal from the head of metal completed by the application of the gas flame ,I

through the aperture 59 into engagement withthe metal which deects it up into the mold.

With the `parts of the mold in the positions which they assume in Figs. 7 and 8,-the mold is tilted toward the right on its trunnions 42, and the free surface 65 of the metal gradually progresses up the conduit 60 and conduit [25 in a solid stream in such manner that the molds are filled without any splashing or any contact with air other than that which happens to be in'the ladle or in the mold cavities.-

The amount of` oxygen in this air is reduced to4 a minimum on account of the application ofthe flame, which carries products of combustionup into thevconduit and tends to drive out the all'.

When the mold has been filled, the ladle may be immediately tiltedv back, and it is found, as a matter of practice, that this tilting operation may be accomplished quite quickly with hardly any hesitation, as the mold fills immediately, and the metal begins to congeal in the mold, beginning at a point farthest from the filling openings, v and maintaining a gradient of heat', the temperature increasing from the remotest part of the mold to the flllin'g opening. l

This is also true down to the metal in the ladle,

which has the highest temperature of any metal in the assembly because the metal in the ladle is the source of the heat for the metal in themold; and the mold, being more remote from the ame, is necessarily cooler than the metal in the ladle,

particularly after the mold has been filled.

l pletely cover the discharge opening 60 inside the ladle chamber 49 when full tilting is reached. When the ladle is tilted back to vertical position,

' as shown in Fig. '1, congelatlon has taken place in the mold' cavities, shrinkage has been taken up, and congelation has partially taken place in the conduit |25, so that something likea tube is formed, the metal running back out of the hol- .The next step is the cutting off Aof the sprue of each slug or casting immediately adjacent the side surfaces of the casting. This is accomplished by movto that of'FigsJlO and 1l.

,flxheznext step is the Vcompletecutting off of the4 'larger'tubular sprue and the opening of the molds so that the castings and detached sprue may "ne which is impressed upon the mold cavities. By removing the castings from the mold immediately after they have congealed, any additional shrinkage may take place without inducing any undesirable strains because the casting is not held by any mold, nor, is there any contract-ion or strain brought upon the casting by shrinkage of the sprue.

Castings made according to the present invention have a smooth surface, which may be immediatelyv subjected to a polish, and therefore many articles which 'may be made by casting can be manufactured with 'a minimum amount ofy labor. Knives. forks, spoons, 'and other tableware' show a remarkably smooth finish without necessity for any machining or other smoothing operations except polishing.

' The slugs which are -made according to the present method have smooth surfaces without defects. y There are practically no inclusions or faults or different sizes and shapes.

As distinguished from the tubular members which were made out of blanks that came from sheet metal, the drawing may be accomplished with my blanks without laboring of the machinery, as the metal is much more )easily worked. Furthermore, the large percentage of defective boxes, which result from the methods of the prior art, is not present according to my method, as

practically all of the tubular members are perf fect. There is a large saving in the cost because clean scrap or ingot metal is much cheaper than the sheet metal of which the blanks were made according to the prior art.

In the castings made according to the present invention approximately fifty per cent vof the sprue runs back into the ladle so that this effects a large saving'in the remelting of metal j due to the fact that the sprue is hollow and thin.

One of the most important features of the inventiony is the location of the mold at a predetermined angle so that the metal wells up in the mold without splashing or spurting. The action ls merely a uniform raising of the level from the lower part of the mold.

Another` important feature of the invention is the provision of a filling opening for the mold, which is commensurate with the size of the mold cavity.

Insome embodiments of the invention, such as the casting of metal plates, the opening of the mold may extend across the full cross-sectional area of one end of the mold. This is to be carefully distinguished from methods in which there isa small opening in which the metal would spurt up into the mold instead of welling up gradually 76 according to the present method.

large and the metal a' In other embodiments of the invention the lling opening of the mold does not necessarily cover the whole cross-sectional area, but it is a relatively large opening for filling the mold and always located at the lowermost corner or prtion of the mold.

According to my method, no part of the melted metal is separated from the compact stream of melted metal Welling up into the mold. Any liquid metal which has separated from this compact stream surrounds itself immediately with oxygen and will not fuse again in the mold to make a homogeneous structure. The arrangement should be such as to provide an uninterrupted stream of metal of large cross-sectional area passing uniformly into the mold.

While I have illustrated a preferred embodiment of my invention, many modifications may be made without departing from the spirit of the invention, and I do not wish to he limited to the precise details of construction set forthybut desire to avail myself of al1 changes within the scope of the appended claims.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. The method of casting which comprises maintaining a supply of clean molten metal in a substantially closed container having a mold I' provided with `a lling opening applied directly to a discharge opening of said containen'maintaining a neutral atmosphere in said container by projecting a flame in said container in suchv manner as to heat sai-d iilling opening, causing said molten metal to ow upward from the illling opening .located at the bottom of the mold in a substantially solid stream into a mold cavity Without splashing, maintaining a heat gradient from the extreme portion of said mold cavity to the supply of metal whereby the casting congeals at its remotest part rst and at its lling opening last, and supplying additional metal to the moldcavity while shrinkage and congelation takes place by means of a head of metal impressed upon the mold cavity, the -mold being made of another metal of higher melting point, whereby the castings may be polished without intermediate smoothing operations, and cutting off the sprue of the casting immediately adjacent the side of the casting promptly after congelation of the metal in the mold cavity.

2. The method of 1casting which comprises maintaining a supply ofclean-molten metal in a substantially closed container having a mold provided with a lling opening applied directly to a discharge opening of said container, maintaining a neutral atmosphere in said container by projecting a flame in sai-d container in such manner as to heat said filling opening, causing said molten i metal to flow upward from the filling opening located at the bottom of the mold in a substantially solid stream into a mold cavity without splashing, maintaining a heat gradient from the extreme portion of said mold cavity to the supply of metal whereby the casting congeals at its remotestpart ilrst and at its lling opening last, and supplying additional metal to the mold cav- -ity while shrinkage and congelation takes place by means of a head of metal impressed upon the mold cavity, the mold being made of another metal of higher melting point, whereby the castings may be polished without intermediate smoothing operations, cutting ot the sprue of the casting immediately adjacent the side of the casting promptly after congelation of the metal in l 14 the mold cavity, and promptly removing the casting fromits mold after congelation to permit furtherl shrinkage of the casting `without restraint of the mold or sprue. 3. The method of casting, comprising maintaining a supply of molten metal in a closed ladle having a mold with its filling opening applied directly to said ladle, maintaining a neutral atmosphere insaid container by projecting a flame into said container to engage the lling opening of said mold, filling said mold with molten metal from said container by causing the molten metal to ow upward from the lling opening located at the bottom of the mold and maintaining a gradient ofheat in said mold and casting dimin-` ishing from the filling opening of said mold toward the remote parts of said mold whereby the casting congeals from the remote parts of said mold toward said filling opening while metal is being supplied under pressure to take up the shrinkage of metal in the mold, and separating the mold and the casting promptly after congelation in order to permit the free contraction of the casting in the subsequent cooling thereof.

4. The method of making castings which comprises maintaining a supply of molten metal in a, substantially closed and heat-insulated container having a mold attached directly to said. container, maintaining a neutral atmosphere in. said container by projecting a ame in said container to engage the free surface of the metal and to be deected backward into the mold, and tilting said container and mold until the metal wells upward into the mold from a filling opening located at the bottom of the mold to form a casting.

5. The method of making castings which comprises maintaining a, supply of molten metal at predetermined temperature in a substantially closed and heat insulated container having a mold attached directly to said container and communieating with said container through a filling opening, projecting a flame into said container to engage the free surface of the metal and to be deilected backward into the illling openingof the mold to maintain a neutral atmosphere and effect a heating of the filling opening of the mold, tilting said container and mold until the metal wells upward in a solid stream without splashing or separation from the lling opening located at the bottom of the mold into the mold to fill` the mold, and thereafter impressing a gravity head of metal in the ladle on the metal in the mold while the metal in the mold cools and solidies from all sides inward toward the center of the casting and toward the lling opening to provide additional metal to take up shrinkage during the congelation of the casting.

6. The method of making castings which comprises maintaining a supply .of molten. metal at predetermined temperature in a substantially closed and heat insulated container having a mold attached directly to said container and communicating with said container through a illling opening, projecting a ame into said container to engage the free surface of the metal and to be deected backward into the filling opening of the mold to maintain a neutral atmosphere and effect a heating of the lling opening of vthe mold,

tilting said container and mold until the metal 15 l from all sides inward toward the center of the casting and toward the filling opening to `provide additional metal to take up shrinkage during the congelation of the castin, and cutting oil the sprue of the casting immediately adjacent the face of the casting while the casting is in the mold, after the casting has congealed to the point o! cutting.

7. The method oi making castings which comprises maintaining a supply of molten metal at predetermined temperature in a substantially closed and heat insulated container having a mold attached directly to said container and communi- 16 tilting said container and mold until the metal wells upward in a solid stream without splashing or separation from the filling opening located at the bottom of the mold intothe mold to illl the mold, and thereafter impressing'a gravity head of metal in the iadle on the metal in the mold while the metal in the mold cools and solitliiles4 from all cating with said container through a filling open-v ing. projecting a' dame into said container, to engage the free surface `oi the metal and to be detected backward into the illling opening of the mold to maintain a neutral atmosphere and ef- -tect a heating of the filling opening of the mold,

sides inward toward the center of the casting and toward the filling opening to provide additional metal to take up shrinkage during the congelation of the casting, and cutting of! the sprue of the casting immediately adjacent the face of the casting while the casting is in the mold, after the .casting has congealed to the point of cutting, and promptly removing the casting from the mold to permit the casting to cool Aand shrink without consti-aint of the mold after removal oi the sprue.

CARL weisser..

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