US1501337A - Rotary casting - Google Patents

Description

A. M. HENRY ROTARY CASTING Filed'May 24. 1921 3 sheets-sheet l INVENTOR.

July 15, 1924.y r1,501,337

\ A. M. HENRY f ROTARY CASTING Filed May 24. 1921 3 Sheets-Sheet 2 IN V EN TOR.'

' A. M. HENRY` ROTARY CASTING Filed May 24. 1921 3 Shets-Sheet. 5

fig. 1 5

' INVENTOR:

atented July l5, w24

AUGUSTUS M. HENRY, F BROOKLYN, NEW YORK.

ROTARY CASTING.

Application filed May 24, 1921. Serial No. 472,169.Y

To all whom t may concern.' Y

Be it known that LAUGUSTUS M. HENRY, a citizen of the United States, and a resident of Brooklyn, New York, in the county of Kings and State of New York, have invented certain new and useful Improvements in Rotary Castings, of whichA thel folvlowing is a specilicatio This invention relates to centrifugal or rotary casting, and aims to provide apro'cess of and apparatus for making, reliably,

economically and rapidly, ferrous castings preferably of ring form.

A particular object of the invention is to provide a process and apparatus as just indicated for the manufacture of iron castings for piston-rings, which shall be of highquality cast ironso far as the known metallurgical requirements of a theoretically perfect piston-ring are concerned,

I-Ieretofore, in the manufacture of such castings by the rotary casting method, that is, by the employment of rotating moulds, attempts have been made to use metal 5 moulds. This, of course, has resulted in the casting of` hard white cast iron, utterly useless for machining into a piston-ring. Attempts were then made to anneal such castings to convert them into soft. gray iron castings, to permit them to bemachined or inished as is necessary, onV a lathe, grinder or the like. But then an apparently insuperable difiiculty presented itself, which may be explained as follows: In the first place, the purpose of the annealing was to convert the combined carbon characteristically inthe hard white iron, into graphitic carbon, the carbon form characteristic of soft gray iron. But it was found that at all times and in every instance, the conversion of the combined carbon into graphitic carbon resulted in the graphitic carbon being inally arranged as temper carbon. Temper carbon, however, is the characteristic of 1 malleable iron. Malleable iron is entirely unsatisfactoryr for piston-rings-indeed, 'is positively destructiveofthe cylinder against which it rubs in operation; due to its toughness and what may be termed its relative plasticity, causing its edges to feather or form minute comb teeth or Scrapers. These Scrapers or feathers chew away the cylinder lining in very quick time.

Acquainted with these facts, I tempted to usevarious mixtures of ordinary high-quality foundry sand .and even core mixtures as a lining fora rotating mould, so that the molten iron admitted to the mould would f thenlcongeal against the refractory moulding-surface thus provided, thereby toavoid ,chilling the casting, and so obtain a soft `gray iron directly as a result of the casting operation, thereby in turn obviatingthe capacity for satisfying three requirements at once. That 1s to say, the ideal or theoret'- ically perfect piston-ring is one which, when actually in operation on apiston in the cylinder of an wear and so preserve the cylinder against all wear; which will continuously prevent the escape of any of the compressed fluidsv from'behind the piston; and which will have very long life. I have found that the ability of a piston-ring to satisfy these threeire.- quirements varies directly asfthe fineness and uniformity of size of the carbon particles, `provided these. particles are finely and uniformly distributed, and provided further that these particles are all graphitic carbon and yet not oftemper form, and are dispersed as above throughout. a mass of densified 'or compacted iron. In this iconnection, I may add, or rather point out, that an iron casting having its graphitic butA engine, will itself take up all non-temper `carbon constituted and di/stributed as just )described and having its main ferrous mass densified or compacted as just described, is of course exceedingly desirable .for very many types of centrifugal castings of annular, arcuate or other-cross section, aswell as for piston rings.

I have found also that such a carbon distribution in the castV iron may, and apparently only may be accomplished when the rate of congelation of the molten iron, after the latter has been deposited in the lrotating mould, is quicker than the rate at which such metal congeals in a xed sand mouldor in a rotating mould lined with mixturesof ordinary foundry sand and other `inirst at gredient's.

One feature of the present invention,

therefore, is the process of making annular articles by' rotary casting, which includes providing a mould, rotating the mould, and depositing molten iron in the mould, while controlling the time of solidification of the iron, relative to the time required for the iron to become predeterminedly deposited around the mould, so that the iron solidiies in less time than iron similarly cast in a mould having molten-iron-contacting surfaces of the usual foundry-sand type, and yet so that the iron requires a long enough time lto solidify, relative to iron similarly cast in a permanent mould having molten iron contacting surfaces of metal, to prevent chill, that is to say, the hardening or partial hardening of the casting as white iron rather than gray, due to the carbon content being in the combined rather than in the graphitic form. Preferably, such process is so carried out that the iron solidies into the predetermined shape within less than one minute, to cause a ne distribution of the combined carbon, but after theexpiration of at least live seconds, to prevent chilling. Good resuits are also obtained where the congelation or solidication control is such that the iron nally and rmlytakes the shape predetermined for the casting after the expiration of three seconds, a full second, and even onef half of a second; and where the setting of the molten iron occurs within considerably less than one minute,l as good results'are obtained when the iron sets within something less than ten seconds after admission to the rotating mould.

Y A very satisfactory means 'for carrying out the discovery just defined, as I have Aproved by actual workings, is obtained by using a rotating mould made up of, or lined with, carefully shaped pieces of greatlyL compressed refractory material of a kind Whose high refractory quality (that is, whose resistance to melting or"'deformation or disintegration-due to high heat is very great) and whose relative rate of heat absorption and radiatin, may be readily predetermined as the result of the ingredients 'and methods of admixture and bondingcinto therequired article. It will be understood that the justmentioned qualities, of the shaped pieces will predetermine absolutely the rete of heat release of the molten iron, and hence predetermine absolutely the rate f congelation of the iron; all other things, and particularly the composition of the molten metal and the centrifugal force factors of the rotating mould, being equal. Said qualities, I find,

at least in the case of the materials tested,

may be thus predetermined in advance by properly selecting the ingredients of the first batch mixturel out of which the pieces' are to be formed, and by forming such pieces from the batch mixture as the result of two sequential manufacturing steps. These two perature employed is. 2800 to 000-degrees Fahrenheit. The ingredients used in mak-y ing the batch mixture for the pieces tested are in the case of said krausgrainclay bases or rogs, preferably in fine particles and pre erably so treated that such particles are in another physical 'form than that of the usual crystals. As to this phase of the invention, however, I do not wish to be limited to the use of any particular mixture or mauterial for, the mould lining; provided only,

of course, that the lining used should, for practical casting on a real production basis, be one such that the shaped pieces may be shaped or moulded accurately and so as to have mould surfaces of as fine and smooth texture as possible; bearing in mind also that such pieces should be s o made as to have as-great permanence as possible, in regard to deferred chemical reaction between the materials of the pieces and the ingredients of the molten iron, and particularly in regard to the formation of silicon and iron compounds which would have the effect, I have found, of bonding the casting to the mould lining and so causing removal of the former to ruin or injure the latter;

in regard to resistance to repeated temperature-change shocks; in regard to resistance to .abrasion by the moving molecules of the molten metal before the casting congeals; and in regard to toughness and strength in withstanding chipping, flaking, splitting or other damaging from the momentary slight expansion of the molten "iron which apparently occurs at the instant of solidiication as a preliminary to a @subsequent v and greater contraction of the metal during `its cooling peridd.

In actualftests, I have found several materials produce desirable results, and par- .ticularly sillimanite;V krausgrain and carbon. Such sillimanite is, a product of. the Norton Co., Worcester, Mass., also sometimes called alumdum; with the base alumina rather than silica. Such krausgrain is a product) of the Krause Research Laboratories, New York, N. Y. Thel carbon used was that as commercially placed on the llO market in thick slabs or blocks b the National Carbon Co., New York, N. which carbon is of the kind often called as-carbom-such as is used for making arcing electrodes for electric furnaces and arc lights and for' makingthe brushes for dynamos carbon is used, however,l a more desirable.

' specific use of carbon as a mould lining for strong and tough state characteristic of substantially pure ungraphitized carbon.

If sillimaniteor krausgrai is used, a piston ring` casting meeting the above indicated requirements is produced, and, further, a p1ston ring casting not requiring a subsequent heat treatment of any kind to adapt it tov its appointed work. If gas mould lining isy provided for certain kinds of castings than when sillimanite or krausgrain is used, especially so far as resistance to cracking due tozan extra high and sudden heat shock, is concerned; but then it is desirable to subject the casting to such subsequent heat treatment if the casting is to be subsequently finished off by turning or otherwise for use as a piston'ring. Onv the other hand, however, if such casting is to be used for other purposes than for making piston rings, as, for instance, for making ferrous metal rims for railroad car-wheels, such subsequent heat treatment may be dispensed with, even in the case of a casting made in a mold with a carbonlining, because then the casting vwill not require subsequent finishin as above yand the casehardening found at the outer peripheral surface ofthe. casting will be advantageous' rather than otherwise. In this regard, lthe deliberately obtaining such a case-hardened casting, for use in various industries, is fully discussed and claimed in my co-pending application filed October 9, 1923, Serial No. 667,524.V i i A further particular object of the present invention is to provide a process, auxiliary to that just described, for the reliable, economical and rapid handling of the molten metal and the piston ring castings made from such metal, while controlling, as above explained, the character of the metal at all times during. such handling; and to provide novel apparatus to facilitate all the processes involved.

Heretofore, in the attempted manufacture of piston-ring castings by powerdriven machines including rotary moulds, machines having acapacity of one ringper mould-carrying-rotor per molten-metal-pour have been apparently sup lanted by machines having a capacity o a plurality of rings per mould-carrying-rotor per molten-l metal-pour. The reason for this has been that machines of the first class, hereinafter referred to as machines of the unit-castin type, have 4been altogether Ltoo complioatet, bulky and slow for rapid and economical production. of thesecond class, hereinafter referred to as machines of the multiple-casting type, havepbeen foundunsatisfactory becausev the castings have not been accurately formed to the precise dimensions predetermined. Such an accurateJ casting is of the highest importance, because after the founder has delivered the casting to the machine shop,

the most expensive paia; of the manufacture of the piston-ring commences, its machining to specifications. lThere should of course be enough surplusmetal all over the ring casting to permit machining all over,

On the other hand, machines' yet the amount of surplus metal should be uniformly thick all over and as few thousandths of an inch thick as possible, to standardize the finishing of the various surfaces, and to minimize. the time and expense of the entire machining operation. It will be understood, then, from what is known in the art, that when a single metal pour, made by means of the familiar elongated tilting i feed-trough or ladle inserted within the rotatin mould, is made relative to a line of annular grooves arranged side by side in the mould of a machine of the multiplecasting type, identical portions of themolten metal are. seldom if ever discharged into all the different grooves. As a result, thel various individual rings, each of which is supf posed to be congealed in one of the grooves. as the mould continues rotation, are of different dimensions, so far as their inside 'diameters are concerned, and sometimes of different shapes, so far as their inner peripheral surfaces are concerned. I

According to the present invention, however, the rapid production advantages of the multiple-castingtype machine .are preserved -in a unit-type casting machine by aV novel process of operating a unit-type casting machine of new and improved form. So far as such novel process is concerned,

in relation to the operation of vsuch unittype casting machine, the. present invention' may bebriefly described, in that particular, as involving the art of manufacturing annular articles by the rotary casting method, which includes, providing a two-part mould, se arable axially of the annular article wfien cast,rotating the mould parts s1- multaneously,introducing molten metal within the mould,-continuing such simultaneous rotation ofthe mould parts until the article,`v is solidiied,-separating the mould parts axially while both continue rotation, to permit extraction of the cast ar-` ticle,-and then bringing the mould parts together to reconstitute the mould for a subsequent casting operation; whereby during a plurality of successive casting operations at least one of the mould parts is continuously rotated by suitable power-means. According to this arrangement, since at least one of the mould parts continues rotation at all times, centrifugal force is permitted to act positively to facilitate ejection of the cast article. Expressed in another way, the inventiorf attains its rapid and efficient production possibilities as the result of providing a unit-type casting machine wherein the mould-carrying rotor is continuously driven at a constant speed by suitable power-means during the casting and ejection of a plurality of piston ring castings,- such castmgs being made within the machine, and ejected therefrd'm, one after another; and this end, turn, is accomplished by separating axially the parts of a multipart rotating mould while....the main or power-driven part is power driven as above.

In the preferred embodiments, the complementary part of the mould is arranged to rotate frictionlessly and hence on momenturn during the period of separation of the mould-parts and during the ejection of the casting just previously made, which ejection takes place coincidently with such period of separation. As a result, when the mould parts are a ain brought together, immediately after t e ejection of said castings, friction between mutually engaging surfaces of the two mould-parts permits the wer .means instantaneously to resume driving both mould-parts simultaneously and positively, and incidentally before the momentum of the complementary mouldpart is so much dissipated as to cause a material speed variation of, or impose any sudden load-shock on, the power-shaft. i

Such features ofthe invention are embodied, preferably, in a quantity-production machine of the turret type, that is, a machine eomprising essentially a turn-table on which are mounted a suitable plurality of simultaneously and continuously rotating mould-carrying roto`rs, arranged radially on the table. During production, the table rotates so that each rotor, in turn, first passes a feeding station whereat a charge of molten metal is delivered to the rotor,-then traverses a pathl of suchlength 4that the time of traverse is just that required to solidify and congeal the ring castin sufficiently to permit harmless centrifuga ej ecl tion',then passes an ejection station, whereat a fixed cam-rail or the like automatically engages an instrumentality on the rotor to separate the complementary mouldpartjfrom the main mould-part of that rotor to cause ejection of the castin into a -suitable fixed receptacle,-and fina ly, and immediately thereafter, again passes the feeding station, for a second charge of molten metal, as before; all a's willvv be more of metal and so predetermining a castingV of accurate dimensions all over.'

The process as above described, it will be seen, has the important advantage, among others, of dispensing with the necessity of any tangible' means for ejecting the casting during the period of separation of the mould parts. Such casting is ejected in the smallest fraction of a second imaginable, by the same intangible means which functioned to form, congeal and densify the molten metal admitted to the rot-ating mould to make the piston ring casting itself,-the intangible means of centrifugall force.

Still a further object of the present invention is to provide a process of and apparatus for the'making of a piston ring castin in a rotating mould which will at once acilitate the feeding of the precise quantity of molten metal desired for each casting operation, facilitate the quick and uniform circumferential distribution of such molten metalwithin the mould, expedite the congela-tion and rate of solidification of the metal, increase the density of the metal as finally set in the casting, and form an almost perfect cylindrical surface for the inner peripheral face of the casting. I have discovered that all these highly important practical effects may be brought about if the axis of rotation of the mould be maintained continuously at an inclination removed from both the horizontal and the vertical; best results so far having been obtained when the mould axis is maintained at or substantially at 45 degrees to the vertical.

The apparatus I have sofar found the best for carrying out this feature of the process just last referred to, is embodied in a powerdriven mould comprising a disc fixed perpendicularly on the upper end of a shaft arranged for rotation about an axis inclinedas above specified, the upper side of the disc having mountedthereon for rotation theresurface of the central portion of the disc;

all as will be'more clearly understood hereinbelow when the disclosures of the drawings are described in detail. t

Preferably, of course, the three annular walls just mentioned are each either con structed of a single piece of the refractory material above described or built up of a plurality of such pieces; in which case the delayed rate of congelation and solidilication of the molten metal, resulting from the heatrefractory nature of such material, increases and intensifies the beneficial effects caused by the process of making the casting in a rotary mould on anV inclined axis pursuant to the preferable method of carrying out the invention.

Preferably, further, in the case of operating and controlling the mould and the action of its molten metal contents by rotating the mould on a continuously maintained inclined axis as specified, the above-explainedy process of providing -a-multi-part mould and axially separating the two parts of such mould to cause centrifugal ejection of each ringcasting as made, is utilized. According to this preferable mode of combining all the various mechanisms and processes herein disclosed, all their separate advantages are simultaneously retained, and at the same time a further important advantage is secured in regard to the automatic or centrifugal ejection of each ring casting at the appointed instant. 'Ihis last advantage, fiowing -from the fact that the mouldsl axis of rotation is inclined both to the vertical and to the horizontal, may be explainedas follows: If the axis of the mould is horizontal, that is, if the ring is cast in a vertical plane, centrifugal force, I have found, will tend to eject the casting prematurely, that is, before the mould parts are completely separated, f

resulting in a comparatively quick destruc tion of the adjacent exposed portions'of the comparatively brittle mould pieces, necessarily separated when the mould-partsare separated. If the axis of the mould is vertical,

that is, if the ring is cast in a horizontal plane, centrifugal force may not absolutely be relied on to eject the casting, since, on separation of the mould parts, the center of mass of the cast ring will be, and in many cases will`remain for some seconds, concentric with the, axisvrof rotation of the mould; and centrifugal force will not funcytion at all in the direction of ejccting the is inclined to both the vertical and the horif zontal, as herein disclosed, the ring is cast in a similarly inclined plane, and I have found that the separation of the mould-parts always occurs before the ring casting may damage the moulding pieces; while on the other hand, as soon as such separation is complete, that is, as soon as the complementary mould-part is completely raised away from above the ring and the lower main-mouldpart, gravity is sufficient to just overcome friction between the ring and the. mould-part supporting it. Thereupon, the ring drops slightly, so-that its center of mass is slightly below the center of rotation of the main mould part; whereupon, instantaneously, the ring is ejected with lightning speed-`- and always in a downward direction, and without danger to the workmen.

`The invention will be more clearlyunderstood from the following description, when taken in connection with the accompanying drawings, illustrating preferred types of apparatus to facilitate carrying out the various processes involved.

In these drawings Fig. `1 is a vertical axial section illustrating one embodiment of the invention;

Fig. 2 is a side elevation of the parts shown in Fig. l, partially broken away, and looking to the left in Fig. 1';

Fig. 3 is a horizontal section, taken on the line 3-3 of Fig. l;

Fig. 4 is an enlarged detail view of certain of the parts shown in Fig. l;

Fig. 5 is a top plan view of a four-part wedge ring shown in section in Fig. 4;

' Fig. 6 is a sideielevation of the ring shown in Fig. 5;

Fig. 7 is a view similar to Fig. l, but showing a di'erent embodiment;

Fig. 8 is a view showing the parts of Fig. 7, when viewed in the direction of the arrow 8 of Fig. 7;

Fig. .9 is a view showing certain of the parts shown in Fig. 7 when viewed in the direction of the arrow 9 of Fig. 7;

Fig. l0 is a perspective view of one of the parts shown in Figs. 7, 8 and 9; t

Fig. ll is an enlarged view of certain of the parts disclosed in Fig. 7, but swung around in a clockwise direction so that yparte which are inclinedk in Fig. 7 are vertically arranged in F ig. l1;

Fig. l2 is a vertical axial view of a tur ret-type machine for quantity production, including several radially arranged' rotors.

with such rotors arranged 'on axes inclined 5 also in Fig. 12.

Similar reference characters refer to similar parts throughout the several Views of the drawings.

Referring t0 the construction shown in Figs. 1, 2, 3, 4, and 6:

The machine shown here is not atA the present time deemed the preferable one, but has shown certain practical values. This machine is one wherein the sep-arable mould is mounted on a vertical shaft 16, adapted to be driven by a belt or the likeMpassing over a pulley 17 fast on the shaft.

The multi-part mould comprises an up-per mould-part 18, which is the complementary mould-part, and a lower mould part 19, which is the power-driven part, that is, the part which continuously rotates at a constant speed. As will be noted, this part is pinned on the upper end of shaft 16.

Shaft 16 is suitably mounted on antifriction bearings, as indicated at 20, these bearings being housed in the upper and lower portions of a casting 21; this casting being bolted to la suitable table 22.

Referring to the lower mould-part 19, this mouldart carries a central 'circular plate 19a, w ich is fixed to the mould part and may be formed integrally therewith if desired. Mounted on the annular upper face of mould part 19 surrounding plate 19a is an annular pieceof theV refractory material above-referred to, this piece being indicated by the reference character 23. The piece 23 is assembled on the mould part 19 by merely laying it on top of the mould .part as shown and then filling in the annular groove left at 23a with fire clay or the like; so that finally the upper plane surface of piece 23 is flush with the upper plane surface of plate 19a.

The other two annular pieces of refractory material,-one being indicated at 24 and the other at 25, are fiXedly clamped in place within the upper .complementary mould-part 18. The manner in which such pieces 24 and 25 are thus clamped in place'will be describedin the paragraph immediately below; but at this point it may be explained that the idea in thus securely mounting these pieces 24 and 25 in the complementary mould-part 18 is to permit such mould part tdbe elevated relative to the constantly rotating main mould-part 19, so that then the congealed and solidified ring which has been cast in the groove indicated at 25a (formed by the three pieces 23, and 25) will lie on a single plane unobstructed rotating surfacein readiness for centrifugal ejection as hereinafter explained. 5, Referring vnow particularly to Figs. 4, 5

and 6, it will be seen that pieces 24 and 25 are secured in place in a recess 26 on the under side of .complementary mould-part 18,

so that the inner peripheral suriaces of pieces 24 and 25 concentrically surrounda central circular opening 27 in complementary mould-part 18. These pieces 24 and 25 are thus held in place by means of the four-part wedge-ring shown in Figs. 5 and 6 and they are marked 28, 28", 28C, 28d; the

part of the wedge ring shown 1n section in 't number of circumferentially spaced screwsone of which is shown at 30 in Fig. 4.

During the interval when the two mouldparts 18 and 19 are rotating in unison, the upper part 18 is driven by frictional contact with the lower part 19, which latter is ,power driven as above explained by' shaft 16. However, it is not desirable to h-ave such friction set up at the cost of abrasive contact between the under surface of piece 24 and the upper surface of piece 23, as this might cause undue and prematurewear of the two pieces last mentioned. Hence main or lower mould-part 19 is provided withan adjustable ring 34, secured to mould-part 19 by a suitable number of cir- -cumferentially spaced screws one of which is indicated at 32 in Fig. 4. In order onicely to set the height of ring 34, in regard to a particular set of pieces 23, 24 and 25 set up in the multi-part mould, so that, when the mould-parts are close together during a casting operation, an annular rib 33 dependent from the under side of mouldpart 18 will frictionally engagethe upper surface of ring 34, and yet so that while pieces 23 and 24 will not be in -frictional contact they will not be so much separated that molten metal may creep in between the two pieces beyond the bounds of groove 25, the design is such that suitable shims of different thicknesses may be set up below rin 34 around'each screw like the screw 32 o Fig. 4, such shims being there indicated `at 30.

Referring now to the means for axially separating the mould-parts, in preparation for the centrifugal ejection of a ring casting made within the mould when the mould was rotating in the condition shownin Fig. 1: rounding drive-shaft 16, is a lined` sleeve 35. A On this sleeve are a pair of exterior .vertical keys or feathers indicated at 35a in Fig. 3. Slidable on the sleeve, and held against rotation by the feathers, is a collar 36 carrying four upwardly and outwardly iso floating member when the two mo-uld- parts 1,8 and 19 are together and rotating in unison during a casting operation; ring 40 acting as the retainer for a circumferentially arranged series of balls 41. However, when barrel 38 is elevated so that clutch 39 engages ring 40, and is further elevated to cause the upper mould-part 18 to be lifted out-ofv frictional contact with the continuously rotating lo-wer mould-part 19, mould-part 18 will continue to rotate on ,balls 41 astantifriction guides and yet merely on its own momentum-almost at' the speed at which it was rotating with mould-part 19, despite the clutch action functioning between clutch 39 and ring 40. Thus, the moulds will be 'axially separated, the lower or main mouldpart 19 will continue to rotate as before, and the upper mould part 18 will continue also to" rotate, but on its own momentum,v

almost at the same speed as the lower mould part, and yet nevertheless, the two parts.

will be separated sufiiciently and for a long enough time to permit ejection of the casting now lying on lower mould part 1,9 and piece 23.

The design of the partsis such that when the barrel 38 is fully elevated, that is, when it is above its position -cf partial elevation shown, and therefore upper mould-part 18 and ring 40 are so elevated that such parts are above the level of the upper plane surface of the main or power-driven mouldpart 19,y the rotating surface on which such casting rests will be entirely surrounded by the cylindrical inner wall of barrel 38 eX- cept where two' openings 42 and 43 are located, as shown best in Fig.l 2. These two openings will then lie in the same horizontal plane as the line of actuation of a kick-member or jabber 44 shown in Fig. 2.

This jabber 44 comprises, asshownin Fig.

2, a slide rod working through a fixed bearing 45, and carrying at its right end a roller 46. By suitable means (not shown) this jabber may be caused to enter open# ing 42, `when the ring is ready for ejection, to let the roller`46 engage the outer peripheral surface ofthe ring, and thereupon, as the jabber is further advanced, to kick the ring a little off center to-ward the opening 43; whereupon centrifugal force will in-v stantaneously eject thering through said opening 43. 4 5

In order to prdvide a convenient means for elevating the barrel 38 at tlfe'proper times, the casting which'comprises collar 36, arms 37 and barrel 38, also carries, as best sho-wn 45 degrees to the horizontal.

in Fig. 2, offset bosses 47, from which` are pivotally hung a pair of links'48, the lower ends of which are pivoted to a hand-lever 49, fiXedly pivoted to a bracket`5`0, hungv which is shown at 33a inv Fig. 4.

Referring `now to Figs. 7, 8, 9, 10 and 11:

` The machine here shown is a variation from that shown in Figs. 1 to 6, particularly in that the driving shaft 51 for the mould is arranged at an angle of approximately One of the great advantages of this construction, as pointed out above, and as will be more clearly understood from what follows, is that gravity aids centrifugal force in ejecting the ring casting when the latter is solidified, and'more than this, and-of even greater importance, a better and more accurately formed ring casting results.

Here the main mould-part is indicated at 52 and ythe complementary mould-part at 53. The main mould-part carries on its upper side a central plate 53a; at its under side is pinned onthe upper end of ldriving shaft 51. This shaft runs in anti-friction bearings indicated at l54 in Fig. 7, set iny ed to be driven by a suitable belt (not shown) Jor the like.

The complementary mould-part 53A (see Fig. 11) is provided with a`n outer flange 53a having therein a groove'53b constituting as shown the outer race for a circumferentially arranged series of balls 58. The'cooperant inner race for these ballsl is carried by'a groove 59b formed on the upper exteriorof a skirt 60. This skirt is provided with two offset portions 61 through which are passed slide-rods 62 working through bearings/63 on casting 55. The offset portions' 61 of the skirt 60 are suitably pinned to the slide-rods; so that each upward sliding movement of the slide-rods causes an upward separating movement of comple-y also provided as anti-friction members permitting rotation of complementary mould- Shaft 51 has fixed thereon at its lower end. a pulley 57 adaptpart- 53, on Qits own momentum, after the latter hasvbeen moved upward and away from the constantly spinning main mouldpart 52f0r the ejection of a casting just previously made.

Refractory pieces 23,` 24 and 25 are provided as in the case of the embodiment of Figs. 1 to 6, and are preferably fixed to theirV respective mould-parts in the same manner and by the same means as illustrated here and as described in connectionwith said Figs. 1 to 6. l

i In order normally to hold the two mouldparts together, and yet to permit axial separationthereof when desired for the ejection of casting, the following parts are provided: The two lower ends of slide-rods 62 are joined by a cross-bar 64. Expansile springs 65 are arranged as shown normally to hold the mould-parts in mutual engagement so that such parts will rotate as one in unison with shaft 5l. Garried by a cross-shaft surface of main-mould part' 52, commences to drop slightly, due to gravity; whereupon centrifugal force acts, and instantaneously the ring is ejected inra downward direction.

However, in order to provide extra, certain provision against any possibility of such a ring casting, during ejection,n flying upward, possibl to injure a workman, the

skirt 60, it will be noted, is provided with an opening, at 60L on its under side, and the skirt is so designed that when the two mould parts are separated to the maximum, the opening will lie opposite the upper surface of piece 23 carried by main-mould part, 52. In this way, a ring casting may not leave the mould except by a movement downward, that is, through opening 60B. And in order to prevent the possibility, iu the event of a ring fiying upward so far as to strike a part of the skirt beyond the bounds of .said opening, of said casting becoming' injured as the result of impact against Vthe skirt, the skirt is lined with a buer 69. This buffer is preferably formed of asbestos, the betterl towithstand the high i heat `conditions prevailing. I have found it very'convenientto use a length `of ordi-- nary sized asbestos brake-lining.,

In order to permit the angle of the shaft 51 to be altered slightly when desired, the framework comprised of castings 55 and 56 is shown as being provided with a depending i boss formed as a sleeve adapted to take around a suitable transverse shaft (not shown).

It will be understood that such shaft supports the framework and at the same time the construction is such'that the angle of inclination of the mould-shaft 52 may be varied when desired.

Referring now to Figs. 12, 13, 14 and 1.5:

The embodiment here shown comprises a turret-type machine in which a plurality of rotors of the class shown in Figs. .7 to 11 are incorporated, these rotors being radially arranged on a turn-table 78 and .each being of the same construction as the embodiment shown in said Figs. 7 to 11 with the exception that the mould-separating means of said Figs. 7 to 1l (parts 66, 67 and 68) are dispensed with and the pulley 57 is removed. Each mould driving-shaft is elongated, and carries, instead of such a pulley, a beveled gear 71. All such bevelled gears 71 are simultaneously driven by a bevel gear 72. -Referring to Figs. 12 and .15, it will be seen that gear 72 is driven, from a motor 73, by means of bevel gears 74 and. 75 and bevel gears 7'6 aand"77. Turn-table 78 is adapted to rotate about a fixed vertical shaft 79 set in a main frame 80. Table 78 is turned by the following means: the table is a bevel-gear 81 meshing with a bevel .pinion 82 fast on a shaft 83 carrying a sprocket wheel 84. Sprocket wheel 84 is coupled bya chain 85 to a sprocket wheel 86' on a common shaft (not shown) with a worm-gear 87 meshing with a worm 88 on the shaft of motor 73.

Instead of the mould-separating means of Fi s. 7 to 11, above referred to, here each radially arranged moulding unit is provided with a mould-separating means as follows: Pivoted below each unit at 89, as shown, is 'a lever 90 carrying .at its bottom a roller 91. To coact with such means predeterminedly is a xed cam-rail 92, it being understood that each lever 90 is rocked as its unit passes the station whereat such rail is located during rotation of table 78. Referring to Figs. 12 and 14 Secured to the underside of each lever 90 normally hangs as shown in full lines, but on a le'ver 90 passing over cam 92 such lever is rocked to the position shown in broken lines at 90 in Fig. 14.

In operation:

Assume the table 78 of Fig. v13 is rotating in a clockwise direction. Let A represent the metal feeding station. Then B will represent the ejection station. It will vbe seenthateach casting will be congealing and solidif ing as the unit in which it lies is passing t e stations D, E, F, and G. Yet

pouring, and `also ejection, is continuous. The number of stationsbe'tween the pouring and ejection stations, here four, is merely illustrative, as preferably the machine will be so designed that, in view of the number of seconds required between pouring and .cross-section by rotary casting, which includes providing a mould, rotating theK mould, and deposit-ing molten iron in the mould, while controlling the time' of solidification ofthe iron,- relative to the4 time,

required for the iron to be predeterminedly Adeposited around the mould, so that the iron solidifies in less time than iron similarly cast in a mould having molten iron-contacting' surfaces of the usual foundry-sand type, to obtain a very fine, close grain, and yet so that the ironrequires a long enough time to solidify, relative to iron similarly cast in a per-v manent mould having molten iron-contacting surfaces of metal, to prevent chilling.

2. The combination with a rotary casting machine, of a mould therefor includingI a mould body and a lining for the latter including a plurality of preformed shaped blocks constructed of a material having the qualities of being highly refractory to temperatures, at least as high as the lowest practical pouring temperature'of molten iron, of including ingredients none of which will combine with'the!A components of the molten metal in such a way as so to`bond the casting to the lining as to preclude removal of the casting without' appreciable injury to such lining, ofsubstantially absolute resistalice to the abrasive action of the molecules of the molten metal subjected to centrifugal action during rotation of the mould, of substantially absolute resistance to distortion from repeated temperature-change shocks, and of sbstantiallymbsolute resistance to chipping, flaking, splitting and otherdamage from such shocks or from the momentary slight expansion of the molten metal,

if any, at the instant of solidification.

3. The art of manufacturing articlesof annular cross-section by the rotary castlng method, which includes providing a twopart mould, separable axially-of the annular 'article when cast, rotating the mould parts simultaneously, introducing molten metal within the mould, continuing such simultaneous rotation ofthe mould parts until the article is solidified, and then while maintaining the axis of rotation of the mould inclined to the vertical, separating the mould parts axially while at least one of the mould parts continues rotation, to permit centrifugal force to act positively to facilitate ejection of the cast article.

4. The process defined in claim 3, wherein the same further involves maintaining the axis of rotation of the mould inclined to the vertical andl also to the horizontal.

5. The process defined in claim 3, wherein the same' further involves maintaining the axis of rotation of the mould inclined to the vertical substantially 45 degrees away from the horizontal.

6. In a rotary casting machine, combina` tion, a main mould having an incomplete annular moulding cavity, a complementary mould for completing such cavity during a casting operation 'but separable from the main mould axially of said cavity, a powermeans for rotating the main mould continuously during a number of successive casting operations, journalling means for the complementary mould independent of the journalling means for the main mould, the two moulds carrying cooperant surfaces for mu-` tual engagement when the two moulds aret brought together whereby during a casting operation the power-means rotates the two moulds simultaneously and yat the Vsame speed, means for separating the two moulds after the completion of each casting operation, and guiding means carried by one of the moulds for spanning a part of the bounds of the space between the moulds when the are separated, thereby, when a cast article 1s ejected from between the moulds, to direct said article to be ejected by way of another part of said bounds.,`

7. The machine defined in claim 6, wherein the axis of rotation of the main mould is inclined to the vertical, whereby gravity cooperates with centrifugal force in automatically ejecting the cast article after the moulds are separated following a casting operation. l

8. The machine defined in claim 6, wherein said journalling means lfor the complementary mould includes an anti-friction bearing whereby the complementary -mould continues to rotate under momentum during the ejection ofsaid cast article, whereby, in

turn, when the two moulds are again brought casting operation but separable from the main mould axially of said cavity, a powermeans for rotating the main mould continuously during a number of successive casting operations, journalling means for the` oomplementary mould independent of the journalling means for the main mould, the two tio ` driven and being mounted for rotation about moulds carrying cooperant surfaces for mutual engagement when the two moulds are brought together whereby during a casting operation the power-means rotates the two moulds simultaneously and at the same speed,"means for separating the two moulds after the completion of each casting operation, said journalling means for the complementary mould including van anti-friction bearing whereby the complementary mould continues to rotate under momentum after the moulds are separated for the ejection of said cast article, said journallingmeans for the complementary mould including a series of rolling anti-friction elements and an inner race and an outer race, there being also provided a ring member having thereon one of -said races, and a movable member for engaging vsaid ring member to move the same axially of thel mould and consequently separate the complementary mould from the main' mould, said movable member constituting a part ofvsaid separating means.

10. In a rotary casting machine, the combination ofv a. rotor adapted to be poweran axis' obliquely inclined to [the horizontal, said rotor, carrying part of a mould, a sec- `ond rotor carrying a complementary part of saidmould and arranged for rotation about theaxisaforesaid, a frame fixed'againstrotation, anti-friction bearings for the second rotor carried partially by said frame, guiding means for supporting said frame and along which'said `frame is slidable in a line` parallel to said axis, and meansfor sliding said frame on said-guiding means to Sepai rate the two moulds after a casting operation to permit centrifugal force to eject a cast article.

-11. The machine defined in claim .10, wherem said frame carries a shield on' its f upper portion for overlyingthe space between the two moulds when the two moulds are separated as described,to prevent accidental ejection of a cast article in an upward direction.

12. In a rotary casting machine, in combination, a main mould having an incomplete annular moulding cavity, a complementary mould for completing such cavity during a casting operation ybut separable.

cles of annular cross-section by rotary castlng, which includes providing a mould, ro-

tating the mould, and depositing aLvmolten such metal in the mould, while controlling the time of solidication of said metal, rela-y tive to the time required for the same to be predeterminedly deposited around the mould, so that said metal solidiies in lless time than similar metal similarly cast in a mould having molten iron-contacting surfaces of the usual foundry-sand type, to ob- Vtain a very fine', closegrain, and yet so that` the deposited metal requires a long enough time to solidifyfrelative to similar metalsimilarly cast in a-perma'nent mould having molten iron-contacting surfaces of metal, to

minimize chilling.

14. The art of making ferrous metal arti-l cles of annular cross-section by rotary casting, which includes providing a mold, rotating the mold, and depositing 'a molten such metal in the mold, whilel controlling the time of' solidification of said metal, rrelative to the time required for the same'to be predeterminedly deposited around the mold, so that said metal solidifies in less time than similar metal similarly cast in a mold having molten iron-contacting surfaces of the Yusual foundry-sand type, to obtain a very fine, close grain, and yet so that the deposited metal requires a longer time to solidify than similar' metal similarly cast in a permanent mold having molten iron-contacting surfaces of metal.

Signed at New York, in the county of New York and State of New York, this 19th' day of May, A. D. 1921.

AUGUSTUS M.r HENRY-

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