US2224961A - Flask - Google Patents

Description

Dec. 17, J. F HINES 2,224,961

FLASK Filed Dec. 7, i959 2 sheets-sheet 1 ATTORNEY.

INVENTOR.

DBCu 17, J F. HINES 2,224,961

FLASK Filed Dc. 7, 1939 2 sheets-sheet 2 IN VENTOR.

ATTORNEY.

Patented Dec. i7, 1940 UNITED STATES FLASK James F. Hines, Lakewood, Ohio, assignor to Hazel K. Hines, Lakewood, Ohio Application December 7, 1939, Serial No. 307,993

' 6 Claims. (01."22-106) This application is a continuation in part of my co-pending application Serial No, 248,668.

The present invention relates to a flask particularly adapted to meet those requirements t wherein present-day foundry practice is more exacting than previously. The outstanding features of such practice are the employment.Y of much harder molds, the requirement of high accuracy in castings, the requirement of clean castings, greater speed of foundry operation, and less skillful labor in foundries. `To meet such requirements it is necessary to satisfy the following conditions: y

(a.) That each flask half (cope or drag) be the l5 exact counterpart of every other flask half of its group, bothy as to dimensions and as to wall taper; this exactness is to a tolerance on the order of only a few thousandths of an inch, and when the tolerance is exceeded the useful life ofthe flask for accurate work is ended. y

(D) That each cope and eachdrag ofa group fit accurately every drag and every cope, respectively, of the same group, within a tolerance of 3D (1) such pouring isA necessary to give .sharpV denition of the casting but l (2) high head pouring increases the tendency of the mold cavity surfaces to wash, which must `be counteracted by hardness of -the mold.

40 (d) That any jacket of the group fit any mold,v

made by a flask of the group within a tolerance of only a few thousandths of an inch in dimensions and taper;

that the mold will spread out into any lost space between its outer wall and the jacket; such spread will of course cause inaccuracy of the casting by ja corresponding enlargement in the mold cavity. (c) That the flask be instantly removable fromv the mold, no matter how hard the'mold or how tightly it adheres to the flask walls, without hammering, shaking, forcing or other violence.

s (1)v In modern practice the sandmayrbe ,either-z ywalls cannot be broken by merely liftingthe flask,

(l) this is because high head pouring increasesIV the outward pressure inthe mold, with the result ing to hardness equal to that given by the sand slinger; in either case the adhesion to the flask but requires pounding with a maul, which destroys a fiask in about a month of service.

(2) Mauling also breaks overhangsf in the mold cavity, may impair the shape of the mold, or in extreme cases, destroy it.

(3) Snap flasks will not serve because none are capable of standing the destructive effects of jolting and squeezing, maintaining precision of size and taper necessary to produce castings meeting todays standards, vnone including any means for making theA separation of the parts and the return of -the parts accurate on the orderv of aV few thousandths of an inch, none include a mechanism for opening and closing which will be proof against injury from sand or'from rough handling. Such flasks are developed only to a point suitable for use with hand ramming, skilled molders, and tolerances on the order of an eighth of an inch; they have not kept pace with modern conditions.

(j) That the flasks have few moving parts and these very sturdy. v l

(y) That theemoving parts be `protectedfrom sand, from being hit, from being bent or otherwise hurt if the flask is dropped, from beingjammed, or worn, misaligned, loosened, or having their approachA distance altered.

(h) That such protection of the movingparts be effective in the open as wellas in the closed position of the ask.

Inmeeting the modern requirements above outlined, it is impossible to allow such discrepancies as were `acceptable in bygone days, and consequently, although` it has long been knownto use snap flasks, and Ahas long been known to make molds in flasks and afterwards to jacket them,no attention has been paid to maintaining extreme accuracy of such flasks and of the jackets to be lused in connection with them, or to adapting them by structureand characteristics to the requirementof maintaining such accuracy over a long life period, of making them interiitting in a close` rather than'ina loose sense, of freeing them from unnecessary members and projecting parts and so on, of guarding against warpage, of providing adequate bearing, guiding, stopping and positioning surfaces, of )saving small quantities' of Vtime in each operation, and in general of givingequipment whichis thoroughly adapted tov stand up and producesatisfactory results under the rigid 55 and exacting modern requirements, wherein the scrap losses in the` castings, the extent of machining previously allowed, the inaccuracies of results previously tolerated, and the damage to equipment previously considered inevitable, are no longer acceptable to the foundryman.

The flask of my invention is made to give high accuracy, to eliminate the need for rough handdling, but nevertheless to stand rough handling well. It embodies certain improvements over the invention of Ser. No. 246,668, notably eliminating sand strips. This saves four motions with every mold, besides simplifying the manufacture and maintenance of the flask, The operations saved are closing two sand strips after the cope is filled and before it is turned face down, and opening two sand strips after the cope has been set on the drag, before the cope can be lifted off. Means allowing gas escape from the mold walls are also provided. The opening and closingmechanism has also been improved.

The accompanying drawings and following description disclose a preferred embodiment of the principles of my invention, thereby illustrating it, but without limiting it to such disclosure.

In the accompanying drawings Fig. 1 is a perspective showing cope and drag of a flask of my improved construction assembled but empty;

Fig. 2 is a perspective showing a mold made in a flask similar to that of Fig, 1 although of diierent proportions and taper;

Figs. 3 and 4 are greatly enlarged vertical sections taken generally anywhere through an edge of my improved liask and including part of a mold therein, showing respectively the mold tight in the flask and the flask separated therefrom for removal;

vFig `5 is a reduced transverse vertical section through a mold and jacket, ready for pouring;

.Fig. 6 is a perspective showing half of a flask corner separatedfrom its complementary half to illustrate the constructionj Fig. 7 is a vertical elevation of either a cope or drag corner according to my invention, the parts being in closed position and the flask taper being disregarded for simplicity; l Y

Fig. 8 is a horizontal section on the plane 8--8 of Fig. 7 in the direction of Vthe'farrows, showing the corner closed; Y

Fig. 9 is a horizontal section of the plane 9 9v of Fig. '7, showingthe corner open; and

Figs. 10 and 11 are perspectives of the corner unit detached and open, being taken from opposite sides.

In the description for convenience, wall is used to mean either a side or an end of either a cope or a drag, flask section means tWo walls connected by an immovable corner, flask half means either an entire cope or an entire drag. In the claims ask means either a whole flask or a ask half.

My present invention, like that illustrated in my co-pending application, Ser. No. 248,668, provides a liask which has a lateral opening arrangement whereby a corner can be unlocked and the flask sections thus separated a short distance, thereby moving the walls slightly away from the mold' sides to break the adhesion, while at the same time thev sections of each flask-half are always firmly engaged in mutual alignment, andthe aligning means are protected from entrance'of sand or other injury, sothat the flask sections are allowed only averyv limi-ted and.. strictlycontrolled separation,y just suliic'ient fory cally nosed somewhat bluntly as at 26.

the purpose indicated. The alignment guides and the opening and closing mechanism are carefully protected against misalignment, against injury, and against encroachment by sand, by having the major portion of the guides housed and embedded in solid metal, and the opening and closing mechanism partly so housed.

My invention is illustrated in Fig. 1 as applied to two ask halves, of which the cope I is assembled on top of the drag 2 by the usual means employed for such purposes, here shown as conventional pin fasteners 5. Cope and drag are each separable horizontally into two sections or 4`vertical parting faces at diagonally opposed corners, 'I and 8 for the cope, 9 and I0 for the drag. The other pair of corners of each element of the flask are permanently immovable, preferably as sembled as shown in my Patent No, 2,006,240.

In the present invention, no sand strips are used. YThe sand is held in place by a series of shallow ribs I2 on the inner faces of the flask walls, Figs. 1 and 6, in the sides of the mold M, Figs. 2, 3, 4, and 5. Opening the corners 1, 8 or 9, I moves the walls enough to clear the ribs from the impressions, the extent of such opening movement being only slightly greater than the depth of the ribs, just sufficient to allow the flask t`o be lifted off, see Fig. 4. The channels I4 also allow gas which escapes through the mold to vent itself past the jacket J, Fig. 5, to the atmosphere.

'I o'in'su're that the parts will come together to the exact original dimensions and angle of taper and with exact alignment and the rigidity which characterizes a. tight or solid flask, I use a corner construction further developed from that shown in my application Ser. No. 248,668. This corner mechanism is most efficiently made as an assembly to be united to the flask walls by casting, as best indicated in Fig. 8. The assembly includes two parallel plates, 2U and 2|, connected near top and bottom by dowels 25, each plate including a large hollow boss, 22 on plate 20 and 23 on plate lII, outwardly horizontally directed. The bosses are receivedgin appropriate enlargements 22 and 23x in the ends of the respective flask walls, and partly enclosed by the tie` metal 30, Fig. 9. One of the plates, 2i] in this instance, also has integral fingers 28`on its back, bent over as in Fig. 8 before the assembly is castinto place, thus taking rm hold in the Vcast tie metal 3Il in the groove 3 I. on the Wallend.

The preferred form of dowel, best seen in Fig, 8, is cylindrical, shouldered about half its length to bear on the exposed face of theV plate 2l, and having the portion 32-of reduced v diameter projecting backwards through the plate 2I, the eX- tension being circumferen'tiallyy grooved, as shown at 33, or otherwise shaped for a rm hold in the tie metal 3D, Thus the dowels 25ghold the, plate 2| to the tiemetal 30of its corresponding flask Wall end, as well as hold themselves in place. The forward part of the dowel lits closely through the corresponding hole in the plate 26, and is Vconi- The plates andlthe dowels are preferably of hardened steel,.whil`e.the tie metal is preferably aluminum.

Since thelarge forward. cylindrical portion `of each dowel .25 .is longerthanfthe depth of. the sand-.holding ribs I2, and theseparatingmovement .atthe corners isV only slightly greater. than the depth of the ribs, asr seenby comparing Figs. 3 and 4, the largefcylindrical section will never leave its holel'in the plate-20 unless the nut 37 of the opening and-closingmechanismis backedoiffurthertha-will bel done-under working conditions. 'Ihusthe dowel always worksa through a hardened guide (the aperture through 20) into a cavity lin the cast tie metal 30, which cavity it keeps fully closed against access of sand, and in which the dowel yis protected against injury, and the dowel nose 26 seats in the tie metal 3U, so that the corner elements always come back to precisely the same distance apart.

Narrow beading 34 runs along the top and down the inner edge of each plate; the beads face one anotherand slightly separate the faces of plates 20 and 2l! when the corner is closed, so leaving space for escape of sand, which might otherwise prevent .the flask sections from closing 'completely and accurately.

It will be observed that by reason of this protection none of the parts which are depended upon for precision of dimension and taper and for linear alignment are exposed except for the short distance between the faces of plates 20 and 2|, and the seats of the dowel noses 26 are never uncovered in ordinary operation. The corner assembly can economically be of hardened steel, sinc only a small quantity is used, while the softer tie metal 30 protected by the plates 20 and 2l backs up the plates and provides the dowelreceiving cavities, and effectively encloses both ends of the dowels in a solid metal casting. There are accordingly no projecting parts which can be hit and injured by tools, strike on t'he floor if the flask is dropped, etc.

The preferred form of opening and closing mechanism, best seen in Fig. 9, comprises a bolt passing through the bosses 22 and 23, with a 35 cam 36 pivoted to one end and a wing nut 31 threaded to the other. Distance of opening is regulated by the nut, which of course also takes up cam wear. This wing nut is ridged on its inner face to engage notches 38 in the exposed end of the boss 22 and prevent unintended turning. The other end of the bolt is flattened providing a head to receive the split cam 36, arranged as a pair of ears eccentrically pivoted to the head and bearing against appropriate hard surfaces 39 on the end of boss 23, either a removable bushing or integral. A lever 40 actuates the cam, overtravel being prevented by a lug 44 on the flask side, Fig. 8. The closing action of the cam is opposed by a compression spring `4I surrounding the bolt 35 within the bosses 22 and 23.

The ends of the bolt 35, the cam lever 40 and the nut 31 are exposed, but these are largely protected by their position close to or against the ends of the respective bosses 22 and 23, which in turn are embedded in the ends of the flask walls, Figs. 1 and 9. However, the bolt assembly is easily removed by taking off nut 31, and easily replaced. 'Ihe bolt and its attachments do not determine the accuracy of fit of the flask sections;

30 such accuracy depends entirely upon the dowels.

As a matter of convenience, the cam levers 40 may have sockets 45 to receive a rod 46 connecting the levers on cope and drag, as shown in Fig. 1, so that a single motion will open or close both 65 cope and drag. This rod, in the preferred form shown, is slidable in the socket 45 of the cope lever 40, with stops 4 l to limit its sliding, and is no longer than the height of the cope, so that when the cope is inverted for filling the rod will not 70 project above its top, and when set upon the drag the rod will fall down into the corresponding socket in the drag lever.

In more detail, to manufacture the flask, the walls are put at the proper height on a block such 75 as 30 in Fig. 6 of my Patent 2,006,240, the two rigid corners are brought as close together as may bedesired and the two corners which are to be separable are set up against the closed corner assembly. Aluminum or other suitable material 30, Figs. 8 and 9 herein, is then poured into the 5 grooves 32 of the flask wall ends for tie metal substantially as shown in my previous patent, so thatthe completed flask on the forming block is a unit with parts held together by cast metal to exact size according to the setting of the sides on 10 the forming block and to exact taper according to the taper of the block. By such manufacturing method any quantity of flasks may be made up as exact duplicates, exact to the thousandth of an inch in size and to a fraction of a degree 15 in taper, whether made at the same time or different times, and any cope will fit perfectly with any drag of its corresponding series. After the corners are so cast,-the separable corners 1 and 8 or 9 and I0 are opened for insertion of the springs 20- 4|, thus also pulling the large ends of the dowels 25 out of the cast metal 30 behind the plate 20. After the springs 4I are inserted the bolt assemblies are placed and the nuts 31 set up to give proper limits of opening. When the flask sec- 25' tions are reassembled the seating of the dowel noses 26 in their self-made sockets insures exact correspondence of closing dimensions with the size to which originally manufactured. Jackets are made on the same block by the same precision 30 methods, by setting the sides and pouring their corners, whereby the jackets will also fit perfectly as to size and taper upon any molds made by flasks of the same group. It is essential to the production of precise castings that the jacket fit the mold perfectly, both as to size and taper. Otherwise applying the jacket will injure the mold, or the jacket will not support the sand closely against internal pressure of the poured metal, or both these ills will occur, with resulting 40 unsatisfactory castings, reflected in financial loss to the foundry.

It will be appreciated that the foregoing description is of a preferred embodiment of my invention, and is illustrative rather than limiting. 45 The scope of the invention is set out in the following claims.

I claim:

1. In a flask of the character described a corner opening and closing assembly comprising two 50 separate plates each adapted to be cast to one corner of the flask with inner faces toward one another, dowels connecting said plates, a hollow boss on each of said plates said bosses extending oppositely from one another away from said inner 55 faces and horizontally of the flask, a separating spring within said bosses and bearing outwardly in each, a bolt extending through both said bosses, a nut on one end of said bolt and connections between said nut and its corresponding boss whereby the nut may be locked against rotary movement, a cam on the other end of said bolt, a seat for said cam upon its corresponding boss whereby camming action is transmitted directly to the boss.

2. In combination with apair of flask halves, corners adapted to be opened and closed, levers adapted to cause such opening and closing, and a rod slidably carried by one of said levers and slidably engageable with the other of said levers when said halves are assembled into a flask, said rod when engaged with the other of said levers connecting both said levers for simultaneous movement.

3. In a separable corner foundry flask, guide means enclosed within the liask wall thickness at such separable corner, the ilask Walls having grooves deiined up and down their adjacent ends at such corner, said guide means comprising a pair of plates having their faces at angles to the inner faces of the flask Walls, said plates being face to face, each plate extending up and down over one of said grooves, horizontal dowels extending through and closely fitting apertures in both plates, said dowels having their ends in said grooves, metal cast in said grooves upon said dowel ends thereby forming seats for at least one of the ends of each of said doWels to stop the approach of the flask section, and elements in combination with said corners for limiting the separation of said plates to an amount less than the projection of the dowel ends into the cast metal.

4. In a foundry ask having separable corners, Walls adjacent said corners having grooves dened up and down in said ends, plates of the same general height as said Walls, covering the length of said grooves, said plates constituting a pair with opposed faces at angles to the inner faces of said Walls and horizontal dowels having ends passing through each of said plates and projecting into said grooves, and metal cast in said grooves upon said ends, said dowels being shouldered upon one plate and having the ends behind said plate reduced and shaped to engage metal cast in the groove, and having the other end smooth and removable from its seat in the cast metal, and determining by its said seat the closeness of closing of the corner.

5. In a foundry flask having separable corners, walls adjacent said corners having grooves defined up and down in said ends, plates of the same general height as said walls, covering the length of said grooves, said plates constituting a pair with opposed faces at angles to the inner faces of said Walls, anchorage means on the backs of said plates extending into said grooves, horizontal dowels having ends projecting through each of said plates and into said grooves, one of said dowel ends being reduced and shouldered against its plate, surfaces on said reduced projecting end adapted to resist Withdrawal when embedded in cast metal, said anchorage means of one said plate comprising integral extensions oi said plate into the groove, said anchorage means of the other said plate comprising said resisting surfaces on said reduced projecting dowel ends, and metal cast in said grooves behind said plates and upon said dowel ends and other anchorage means, said cast metal also forming seats for the non-anchoring ends of said dowels.

6. In a foundry flask having separable corners, a corner assembly comprising parallel plates secured to the side walls in a corner of the flask and facing one another, guide elementscon nesting said plates for relative horizontal movement, a hollow boss on each of said plates, said bosses extending horizontally oppositely and away from the adjacent faces of said plates, a bolt passing through said bosses, and elements on each end of said bolt bearing upon the corresponding boss, one of said elements on said bolt being adapted to change the distance of opening between said plates, said elements on said bolts being positioned close to the flask Walls and disposed partially Within the overall thickness of said Walls.

JAMES E'. HINES.

Images