US2340262A - Casting machine - Google Patents

Description

Jam 25, 1944- J. F. CRAWFORD CASTING MACHINE Filed Feb. 2e, 1940 3 Shee'ts-Sheet 1 Jan. 25., 1944., J. F. CRAWFORD CASTING' MACHINE Filed Fb. 26, 1940 3 Sheets-Sheet 2 UHHHHHH NVENToR. dorm FA CRAWFORD BYnuw-n. i I1TToRzvEY IIIIIHHHI Jan. 25, 1944. J. F. CRAWFORD CASTING MACHINE Filed Feb. 26, 1940 5 Sheets-Sheet 3 @drm INVENTOR.

JOHN F. CRAWFORD BYMJ/m ATTORNEY Patented Jan. 2s, 1944 CASTING MACHINE John F. Crawford, Racine, Wis., assignor to J. I. Case Company, Racine, Wis., a corporation Application February 26, 1940, Serial No. 320,735

20 Claims.

.'Ifhepresentinvention relates to casting ma'- chines and more particularly `to'such as are intended'forv casting sleeves or other hollow forms.

'An' bject of the invention is to generally-improve'gthe constructionand operation of devices vof class. Alll vfurther object is to provide such'amachine which will have a relatively large Further objects are to provide such a machine Ahaving vva rotatable-ask in which castings may.- bemade repeatedly and as rapidly as they are suf'ciently cooledto stand 'being removed 'fromr the mold; to provide methods'and'mechanism-- for forming a sand mold-within the rotating" ask immediately after leach vcastingisdischarged therefrom; to provide a movable carriage for supporting the rotatable flask and disposing it instance fixed with shaft A. Block 2 carries an arm or support 3 in turn supporting a'bearing head or the like, generally designated as 4, head 4 and motor M constituting the major portions of carriage C. Shaft A also has xed thereon in a position convenient for operation, a hand wheel or similar manually operablee element 5 and an indexing plate 6, Fig. 8,4providingnotches as I engageable in well-known manner with a detent or dog 8 pvoted on akstud 8B or the like carriedv by any convenient fixed part of the ma- 'chinejfor suitably locating carriage C in the ,el-various,necessaryattitudes.

' MtorM drives, through a pulley or thev like 9,

belts :I0- I0 and a pulley Il, a spindle or stem I2 .journaled in head 4 as by means of antiinl various positions or attitudes best adapted for the various operations; and to provide suitable facilities and expedients for the realization of the above objects.

An illustrative embodiment of the machine is described in thefollowing specification and illustrated in the accompanying drawings in which Figure 1 is an axial vertical sectional view taken through the characteristic parts of the machine.

Fig. 2 is a similar view of a portion of Fig. 1 showing the parts in a diierent position.

Figs. 3, 4, 5, 6 and 7 are similar views with other parts removed, showing the parts in various other positions and illustrating various steps in the process of casting a cylinder sleeve.

Fig. 8 is an elevation taken from the opposite side .of the machine from that shown in Fig. 1 and with parts broken away.

Fig. 9 is an enlarged sectional view on the line s-s of Fig. s.

Fig. 10 is an enlarged sectional view on the line Ill-I0 of Fig. 5.

Returning to Fig. 1, the machine in general comprises a base B upon which is mounted for rotation in the present instance about a shaft or axis A, a carriage generally designated as C. Carriage C supports rotatable flask F, a motor M for rotating the flask and various mechanism, and expedients to be more fully described below.

Base B also supports a guide, ram, or secondary carriage G for cooperation with flask F in a manner to be presently explained, the carriage C being rotatable for placing the flask in the Vvarious attitudes indicated in Figs. 1 to 7. for accomplishing the various steps in the casting of a sleeve. l

Motor M is supported as by a suitable bracket I from a clamp-block or the like 2, in the present friction bearings I3 and I4, Fig. 1, of any suitable or preferred type. Spindle I2 may have a ange I5 engaging a base or attaching portion I6 of ask F, and which may be removably secured thereto in any suitable or well-known manner. In the present instance.' bolts as I'I pass through flange I5 and a reinforcing ring or housing I8 enclosing a portion of head 4 and assisting in preventing access of dirt or the like to -bearing I4. By removing bolts I1, other flasks of different sizes or characteristics may be substituted for flask F for adapting the machine to different stylesof castings, although it is to be understoodl that one ask remains in place throughout numerous successive casting operations, the molds being formed directly in the flask and removed and renewed repeatedly as the operation continues.

Flask F carries a retaining ange or closure I9 having an inwardly extending lip 20 and being readily removable from the'ask as by means of a bayonet" s lot 2|, Fig. 6, engaging a pin 22, or other suitable or well-known expedients for holding such a closure in place.

' sary for the operation.

Spindle I2 is hollow in the present instance and carries therein mechanism for actuating a able in fluid tight relation to the bore l25 of spindle l2. Piston 24 is fixed in the present instance with a tubular stem 26 extending lengthwise of the plunger and through a suitable closure or packing 21 into the interior of ask F and being fixed in suitable manner as by a threaded connection 28 With above mentioned head 23.

Piston 24 is also slidable in uid tight relation on the outer surface of a tube or pipe 29 ex-` tending through the major portion of the length of the spindle i2, and ports as 30 in tubular stem 26 provide for flow of fluid from pipe 29 into the bore of spindle l2 about stem 26. Pipe 29 is fixed with a tting 3| extending into the end of spindle l2 remote from flask F, the space about the fitting being closed by a packing or other sealing means 32 to provide for rotation Yof spindle i2 about fitting 3| Without the escape of uid therefrom. Fitting 3| may have a ange 33 for preventing endplay of spindle I2 as seen in Fig. 1. Fitting 3| is prevented from r'tating as by a member 34 clamped or otherwise fixed on the fitting as by a screw 35 and supported from bracket 3 by one or more rods as 36.

A bore 31 in fitting 3| communicates with the bore 25 of spindle I2 exteriorly of pipe 29 and communicates as by a port 38 witha conduit 39 for pressure uid. A bore 40, also in fitting 3|, communicates with pipe 29 and through a port 4| with a conduit 42 also for pressure fluid.

It Will now be apparent that supplying pressure fluid through conduit 39 and exhausting it through conduit 42 will cause movement of piston 24, stem 26 and head 23 to the left as seen in Fig. 1. Supplying of fluid through conduit 42 and exhausting through a. conduit 39 will cause opposite movement of 'piston 24 and its attached parts. Head 23 is so advanced through ask F for the purpose of preliminarlly forming the mold and also form ejecting the finished casting as will appear.

Base B, in addition to supporting shaft A, carries supports or partitions 43, 44 and 45 which cooperate for carrying and actuating a tamping or finishing roller generally designated as 46, for

insertion and operation within flask F at one stage in the making of each mold. In the present instance partition 43 carries tubular element or stem 41. Stem 41 carries a piston 48 about which is slidable in uid type manner a cylinder` or hol- `low plunger 49, cylinder 49 being also slidable within a collar or fitting 50 fixed with partition 44. In this manner cylinder 49 may be extended through partition `44 for a substantial distance without support other than engagement with collar 50 and piston 48. The end of cylinder 49 at the left as seen in Fig. 1, is closed by a packing or other suitable element slidable in uid tight manner on the exterior of stem 41, element 5i cooperating to guide and 69.

Cylinder 49 carries a. ange 52 to which is direct cylinder fixed a fltting 53 having a guide portion 54 which may conveniently be a ange for cooperation with flange 6 2, suitable bolts or other fastenings in the position of Fig. 1, to an extent less than the offset of axle 58 relative to shank 56, although other means is contemplated for offsetting roller 46 when desired.

Flange 54 of tting 53 is adapted to t within guide or collar portion 6i carried inpartition 45 to guide the tting and prevent displacement thereof under the considerableside thrust developed in forming the mold. Flange 54 is so formed as to be freely rotatable within collar 6| when guided therein, and flange 51 is suitably fixed with tting' 53, as for example by la pin or the like 62.

Cylinder 49 has xed therewith as by a clamp 63 engaged with the cylinder as by a screw 64, an actuating handle or element 65, by means of which cylinder 49 may be rotated through a fairly large arc, in the present instance approximately Stem 41 provides ports as 66 adjacent piston 48 and a conduit 61 extending through the stem and through piston 48 to communicate with the space to the right of piston 48 as seen in Fig. 1. A tting 68 is engaged with stem 41 at the left end thereof and has a bore 69 communicating with the interior of the stem 41 and, through a clamp 10, fixed with fitting 68 as by a screw 1|, with a conduit 12. Another bore 13 communicates with conduit 61 and through clamp 10 with a conduit 14. By supplying pressure iiuid through conduit 12, pressure may be communicated through stem 41 and vports 66 to the space between fixed piston 48 and packing 5I, causing movement to the left of cylinder 49 together with tting 53 and roller 46, thus retracting roller 46 from the interior of flask F, roller 46 having previously been shifted to a position where it will clear collar 20, as follows:

Starting'with the position of the parts shown in Fig, 1, cylinder 49 is rotated by means of handle 65 to oiset axle 58 upwardly instead of downwardly relatively to cylinder 49. Owing to the slight downward offset of cylinder 49, roller 46 will thereby be brought substantially coaxial with ask F, or at any rate into a position in which it may be retracted to the left as seen in Fig. 1.

On the other hand, supplying pressure fluid through conduit 14 and exhausting it through conduit 12, as will further appear, develops pressure between fixed piston 48 and the end of cylinder 49 formed by ange 52, thereby displacing cylinder 49 to the right. Assuming roller 46 for the time being to be positioned coaxially with flask F, this movement will result in inserting roller 46 within ask F, at the end of which movement flange 52 will contact collar 6| and locate the roller properly within the flask while flange 54 will seat within collar 6l to brace the structure against side thrust. Handle 65 may then be actuated to offset the roller for rolling or compacting the mold being formed within flask F as will further appear. i

The several steps in the casting of a sleeve may now be understood from the mechanism so far described. Referring to Fig. 2, flask F is first positioned with its axis vertically, head 23 being retracted and forming the bottom wall in flask F in this position, the head being contoured to form the desired distribution of the molding sand in this region. A predetermined quantity of suitable molding sand which may be of any suitable or well-known composition, core sand having been found satisfactory, is introduced into the flask as by a funnel or the like 15, the flask being rst started rotating or spinning by means of motor M. Owing to the rotation of iiask F, the sand will be thrown outwardly by centrifugal force and distributed within the ilask approximately in the manner indicated.

The ask continues to rotate throughout the trifugal force alone keeps the layer of sand 'i6 in place at this stage of the operation.

When the plunger 23 has traversed the length of theask, it is retracted to its original position as shown in Fig. 4, leaving layer'16 complete land of predetermined thickness throughout the length of ask F. When plunger 23 is completely retracted, cylinder 4,9 is advanced by fluid pressure as above outlined, placing roller 46 substantially concentrically within ask F and its lining of sand 16. Handle 65 is then manipulated to rotate cylinder 49 as above described, osetting roller 46 to the position shown in Fig. 1, reducing the thickness of sand layer 'I6 and compacting it to the necessary density for receiving the molten metal. Roller 46 has a collar 'i8 which forms a groove i9 in the sand for forming an attaching flange on the finished sleeve. Other configurations for roller 46 and also for ask F for forming sleeves of varying types or cross sections, are contemplated as part of the invention.

suitable manner, as by tapping on a lug 81 to dislodge it from pins 22, whereupon carriage-C is indexed to place iiask F in the position as shown in Fig. 7. Plunger 23 is then advanced slightly as by .iiuid pressure as above described, which movement breaks part of the sand lining and exerts a substantial pressure on the inner, or what is than the upper end ofsleeve 86, which falls out oi nas! F together with most, it not all ofthe sand lining. Carriage l2 is then indexed again to the position of Fig. 5 and the interior of ask F is cleaned in any suitable manner, as by a swab or the like,

or while stili in the position of Fig, 7 the iiask may be cleaned by the insertion of a nnger 88 guided for vertical movement by suitable or wellknown means not shown, the ask-being set rotating again for this purpose. Finger 88 is so placed that sleeve 86 will clear it when dropping out of the flask, and movement may be imparted to it by hand or otherwise through suitable or. well-known connections not shown.

With the carriage in the position indicated in Figs. 5, 6 and 8, collar I9is replaced, motor M again started to-resume the rotation oi' iiask F whereupon the cycle is repeated, in actual practice a completed sleeve being turned out of the machine about once in every iiveminutes orless.

The foregoing is an explanation of the characteristic features and principles involved in the e invention. Numerous expedients are used for The sand mold or lining is now complete and I may possibly undergo a certain amount of baking from the residualheat in ask F, although this does not appear to be essential for the successful operation ofthe apparatus. Roller 46 is returned to retracting position shown in Fig. 4, and backed out of the mold by means of iluid pressure, whereupon carriage C is rotated or indexed through substantially 180 tothe position shown in Figs. 5, 6 and 8. e

A spout 8G hinged on a suitable support 8l is swung into place with delivery spout 22 projecting within the opening in ange 2D, whereupon a measured quantity of molten .iron or other suitable metal, which will give the desired properties in the casting, is poured into spout d@ and,

owing to the centrifugal force developed by the continued rotation of ask F, with its sand lining lt, arranges itself inthe form of a tube or sleeve within the accurately formed inner surface of the sand lining l5, the sleeve having an accurately formed cylindrical interior or bore 83, Fig. 6.

The heat of the molten metal liberates quantities of gas from the moist sand, as is understood,

which gas escapes through openings or vents 8f3-Sli, formed through the outer wall of iiask F. These openings being of any desired shape but preferably :daring outwardly so that they tend to clear themselves of accumulations oi sand rather than to become packed with the same, and thereby closed. Additional openings 85, similar in character, are provided in iiange 2@ for a similar purpose. Flask Fis allowed to continue to rotate until the interior of the newly cast sleeve d5, as observed through the opening in flange 26, has acquired a color indicating that it has cooled enough to support itself. The rotation of ask F is then stopped and collar it removed in any accomplishing the various above outlined operations, many of which are well-known but which will be described in order to provide a complete working illustrative embodiment. For example, in the present instance to prevent iiask F from becoming overheated, it is provided with anges 89-89 which provide a large radiation surface and help to control the temperature of the flask.

` If desired, a nozzle Sil may be hinged to support 8i or other suitable supporting means and arranged for blowing compressed air or other cooling fluid directly into the mouth of flask F for cooling the castings or the ask or for blowing bits of sand out ofthe ask, or for other purposes.

Head 23, in ,order toprevent transmission of excessive heat to stem 26 and accordingly to the fluid actuating the stem and piston 2d, is made in two or more pieces, as Qi and S2, which are united by bolts or the like S3 and formed to provide a cavity 9d within the head for partially isolating portion 9i from portion 92." Conversely, the making of plunger 26 hollow, and causing the circulation of the duid therethrough by means of pipe 29, on its way to the space of spindle i2 carries away a large amount of heat from portion 92 and assists in preventing. its reaching ex cessive temperature. This is important inasmuch as portion Si is exposed directly to the interior of the newly cast sleeve without the benefit of any sand lining, the latter ending Aat .the outer periphery of head 22 as clearly apparent from Fig. i.

Pressure fluid is supplied for the actuation oi piston .2li and cylinder it as follows: Fluid, for example oil, is contained in a reservoir t5, Fig. 8, and put under pressure in aconduit S6 as by any suitable pump ill, driven through a belt or the like 98 by a motor 9S. Conduit S6 may, for example, lead to a branch i6@ connecting with one or more control valves, in the present instance two, although a single valve is contemplated'having different positions for the separate functions of a machine. Hydraulic pumps, valves, etc., be-i' ing well known, it is unnecessary to describe these elements in detail other than to point out the particular functions that they serve in this organization.

A control valve receives fluid through a conduit |02 communicating with branch |00 and, according to its adjustment, may transfer it through either of conduits and |04, at the same time receiving fluid returning through the other conduit and exhausting it through a conduit |05, connecting withc. branch |06 leading to a discharge or return pipe |01 emptying into reservoir 95.

In like manner, a control valve |08 receives fluid-through a conduit |09` also lcommunicating with branch |00 and discharges it through either of conduits |I0 or III, connecting respectively with above mentioned conduits 1'. and 14. Fluid returning from the otherconduit is exhausted through a conduit ||2 communicating with conduits |05 and |01. These valves |0I.and |08 control the actuation of head 23"and cylinder 49. A relief valve IIIEL provides communication between conduits I00 and |01 and may be adapted to open automatically in the event of the development of excess pressure or under other desirable conditions.

Conduits |03 and |04 must communicate with above mentioned conduits 39 and 42 on carriage C which as above described is rotatable about the axis of and in fact with axle A. To provide for this, axle A, Fig. 9, is preferably although not necessarily tapered as at H3, and a fitting generally designated as I|4 is fitted in a fluid tight manner on the tapered surface.` Fitting I I4 provides grooves or channels I|5 and ||6 surrounding or at least partially surrounding axle A. Above mentioned conduit |03 communicates in any suitable manner with channel I I5 while conduit |04 communicates with channel I I6. Axle A has a port I|1 which registers with channel II5 and communicates with a bore I I8 leading longitudinally of the axle to a point beyond a bearing I I9 carried by base B and serving in part to support axle A. Another port |20 communicates with above mentioned conduit 39 on carriage C.

In a similar manner a port |2| in `axle A communicates with channel I I8 and leads into a bore |22 whichin turn communicates with a port |23 connecting with above mentioned conduit 42. In this manner fluid communication into the movable carriage is obtained so that piston 24 and head 23 will respond to the position of valve IOI.

Valve I0| may be controlled by a suitable handle or other manually operated member |24, Fig. 1.

Conduits 12 and 14 as above described lead directly to fitting 68 and accordingly cylinder 49 will respond to the position of valve |08. Valve' |08 has a handle or similar means |25.

Valves |0| and |08 may be of any suitable or well-known construction, such that controls |24 and |25 will have a neutral position in which no fluid will flow in the conduits controlled thereby,

' or other well-known or suitable ,characteristics such that piston 24 and cylinder 49 may be advanced or retracted or heldin any desired position at will by appropriate manipulation of controls |24 and |25.

Referring again to flask F, provision is made for preventing transmission of excessive heat to spindle I2. For this purpose portion I6 is substantially enlarged in the present instance over the diameter of the major portion of the flask.

Portion I6 is also formed with a cavity |25 so that there is no direct contact of any appreciable area between portion I6 and flange I5. Furthermore, parts of portion I8 are cut away as indicated at |21 between above mentioned screws I1, to further reduce the area of contact between the flask and flange I5. In this manner flask F is to a certain extent isolated from spindle I2 and does not communicate thereto more heat than can be effectively carried away by fluid circulating within spindle l2. The fluid and spindle accordingly maintain a safe and efficient operating temperature.

Dog 8 may be controlled in any suitable or convenient manner, in the present instance a pull rod |28, Fig. 8, being pivoted to the dog at |29 and extending to a clevis |30 pivoted as by a pin |3| to a lever |32 fulcrumed on a pin |33, carried as by a bracket |34 on base B. Rod |28 may be upwardly urged by any suitable means, such for example as a spring |35 compressed between a collar |38 on rod |28, and some fixed element such as a bracket |31 on base B. Lever |32 may extend through base B and constitute a foot pedal |38, Fig. 1. Thus the operator may have both hands free to control hand wheel 5 while clog- 8 is released on pressure of |38.

Spout is arranged so that spout portion 82, as seen in Fig. 10, is offset from the vertical plane of the center line of flask F and toward the side of the sand lining 16 which is moving downwardly by virtue of rotation of the flask. In this manner the molten metal obtains a component of movement by its fall from spout 82 in the general direction of movement of the sand mold. It is unnecessary for the sand lining to assume the entire burden of starting the rotation of the metal from its relatively stationary or only slightly moving condition as it leaves the spout 82. Such a requirement might, under certain conditions, result in a washing away of the sand lining and enlargement of imperfection in the casting in the region where the metal first contacted the sand. This oiset or substantially tangential introduction ,of the fluid metal eliminates this possibility. y

Electric current for operation of motor M may be introduced into carriage C in any suitable or well-known manner, in the present instance slip rings |39 and |40 being mounted upon a body of insulation |4| fixed in any suitable or well known manner on axle A. A wire` or other conductor |42 connected with slip ring |39 and leading into a central bore |43 .in axle A, extends through the bore and a bore |44 within base B to a terminal box |45 or other suitable point of connection with motor M. A second insulated wire |45 extends from slip ring |40 through bores |43 and |44 and also to terminal box |45 as above. Brushes |41 and |48 bear resiliently against slip rings |39 and |40, urged by any wellknown or suitable expedient not shown and connect with leads |49 and |50 leading from a switch |5| connected to a suitable source of energy |52. Leads |52 and |53 also lead from switch |5I to a terminal box or the like |54 on motor 99. With the mechanism above described, the various steps for casting a cylinder sleeve can be carried out as hereinbefore explained. Thus, motor 99 may be operated through the source of energy |5I, supplying fluid pressure to valves |0| and |08 for controlling piston 24 and cylinder 49. Carriage C may be released for rotation by pressure upon pedal |38 and the carriage may be wheel 5.

through fitting H4 and electrical energy for the operation of motor M is introduced through slip rings |39 and |40.

The above being a complete description of a workable illustrative embodiment of the invention, what is claimed as new and desired to be secured by Letters Patent of the United States is:

1. In a casting machine, a sleeve-like flask rotatable about its axis and having an open end,

Aa movable plunger normally disposed at the opposite end of said flask from said open end, means disposed adjacent the open end of said flask in one .position thereof for introducing sand into the open end of said flask, said plunger being adapted to traverse said flask and expel excessive sand through said open end for forming preiiminary rough molds within the flask, means for retracting said plunger, a roller carried by the machine and adapted for introduction through said open end in one position of said flask and to be offset for compacting said mold and forming a finished molding surface, means for retracting said roller` means for introducing molten metal into said finished mold, and means for releasing the resulting casting and the used sand.

2. In a casting machine, a sleeve-like flask having an open end, means for rotating the flask about its axis, means for swinging the flask while rotating to an upright position with the open end up, means disposed adjacent the open end of said flask in one position thereof for introducing sand into the open end of the rotating flask, means for expelling surplus sand from the rotating flask and forming a rough mold therein, means positioned and adapted to be'introduced into said flask and displaceable for compactlng said sand and forming a finished mold, means for locating said flask with its axis in position for receiving molten metal into said mold, means for introducing metal into said mold, means for releasing the resulting casting and used sand when cooled and means for ejecting said casting.

3. In a casting machine a, sleeve-like flask hav- `ing an open end, means for rotating the ask about its axis. means disposed adjacent the open end of the flask for introducing sand into the open end of the rotating flask, means adapted to be introduced into the rotating flask from the opposite end from the said open end for expelling surplus sand through said opening, means introduceable into the flask through said open end for compacting the sand and forming a mold within said flask while the rotation continues, and means for pouring molten metal into the mold thus formed for forming a -casting within.

said mold.

4. In a casting machine a sleeve-like flask having an open end, means for rotating the flask about its axis. means supported adjacent the open end of the flask for introducing sand into the flask while the same is rotating, and means. adapted to be introduced into the rotating flask to urge surplus sand toward and out of the open end thereof.

5. In a casting machine a rotatable spindle,.a ilask carried by said spindle, a fluid motor in said spindle. a plunger carried by said spindle, so disposed as to be actuated by said fluid motor and having a head normally at one end of the flask, and adapted `to be introduced into said flask, during rotation of the spindle 'and ask by said fluid motor, and a source of fluid under pressure connected with said fluid motor 'for actuating said fiuid pressure actuated element.'

6. Ina casting machine, a sleeve-like flask rotatable about its axis and having an open end,`

closing means partially closing said open end, a movable plunger normally disposedA at the end of said flask opposite said open end, means for causing said plunger to traverse the length of said flask, means supported adjacent the open end of said flask for introducing sand into the open end of said flask, said plunger being adapted to expel excessive sand through said open end, means for retracting said plunger, means for compacting the remaining sand and forming a finished mold surface, means for introducing molten metal into the finished mold, means for releasing said closing means for releasing the resulting casting and used sand,.and said plunger' being adapted tovbe advanced to expel said casting from the flask.

'1. In a casting machine a sleeve-like flask rotatable about its axis and having an open end, means supported adjacent said flask for substantial registration with said open end for introducing sand into said flask for forming a mold therein, pressure exerting means insertable Within said sleeve-like flask for compacting the sand and forming a finished -mold within the flask, and said flask providing a plurality of outwardly flared vent holes for the escape of gases developed in the sand mold; the size of said holes 'being so chosen as to provide for the escape of excessive sand to prevent undue compacting of the sand by said pressure exerting means, and means for introducing molten metal into said mold.

8. In the centrifugal casting of molten metals by subjecting a-mold charged with molten metal to the effect of rotation in a casting machine. the steps of rotating a flask and while rotating charging the flask with sand to be acted upon by centrifugal force, scrapingthe sand toa substantially uniform thickness, pressing the sand, charging the finished mold with molten metal and continuing the rotation of the mold while the metal sets.

9. In( the centrifugal casting of molten metals by subjecting a mold charged with molten metal to the effect of rotation in a Vcasting machine, the steps of rotating a flask and while rotating charging the ask with sand to be acted upon by centrifugal force, scraping the sand to a substantially uniform thickness, pressing the sand to produce a suitable density and form, charging the finished mold with molten metal and continuing the rotation of the mold while the metal sets.

10. In thecentrifugal casting of molten metals by subjecting a mold charged with molten metal to the effect of rotation in a casting machine, the steps of rotating a flask with its axis in an upright position and While rotating charging the flask with sand to be acted upon by centrifugal force, scraping the sand to a substantially uniform thickness, pressing the sand to produce a suitable density, shifting the mold to a substantially horizontal position, charging the mold with molten metal and continuing the rotation of the mold while the metal sets.

11. In the centrifugal casting of molten metals by subjecting a mold charged with molten metal to the effect of rotation inea casting machine,

the steps of rotating a flask with its axis in an upright position, and while rotating charging the flask with sand to be acted upon by centrifugal force, shifting the flask to a substantially horizontal position, scraping the sand to a substantially uniform predetermined thickness, pressing the sand to produce a suitable density and to accurately form the desired internal contour of the mold, charging the finished mold with molten metal, continuing the rotation of the mold while the metal sets, shifting the mold to a downwardly directed position, ejecting the casting and sand and repeating the cycle while the flask retains sullicient residual heat to assist in hardening the sand.

12. In the centrifugal casting of molten metals by subjecting a mold charged with molten metal v to the effect of rotation in a casting machine the steps of rotating a flask and while rotating charging the flask with sand to be acted upon by centrifugal force, scraping the sand to a predetermined thickness, pressing the sand to a suitable density; charging the finished mold with molten metal, continuing the rotation of the mold while the metal sets, ejecting the casting and sand and repeating the cycle while the flask retains sufficient residual heat to assist in hardening the following charge of sand.

13. In a casting machine a flask of open ended sleeve like form rotatable about its axis, means on the machine for supporting the flask and shiftable for disposition of its axis at various angles relative to a horizontal plane suitable for consecutive operations in forming a mold and casting within the flask, means on the machine cooperating with the flask in each position thereof for performing an operation requisite to forming therein finished molds and castings, and said flask having means partially closing the open end and movable away from said end for releasing castings formed in the flask.

14. In a casting machine a rotatable spind1e,

a flask carried at one end of the spindle for rotation therewith, means for permanently fastening the flask to the spindle, said means being so shaped as to limit the area of contact available for transmission of heat from. said flask to said spindle, and fluid motor means in said spindle for carrying away heat absorbed from said flask.

15. In a casting machine a sleeve like flask 'rotatable about its axis and having an open end, a movable plunger normally disposed at the opposite end of said iiask from said open end, means partially closing the open end and movable away from said end for releasing castings formed in the flask, means disposed adjacent the open end of said flask in one position thereof -for introducing sand into the open end of said flask, said plunger being adapted to traverse said flask and expel excessive sand through said open end for forming preliminary rough molds within the flask. means for retracting said plunger, a roller carried by the machine and adapted for introduction through said open end in one position of said flask and to be offset for compactlng said mold and forming a finished molding surface, said A molten metal, means for retracting said roller, and means for introducing molten metal into said finished mold.

16. In a casting machine a sleeve like ask rotatable about its axis and having an open end, a flange adapted to partially close said open end and movable away from said flask for releasing the contents thereof, means for introducing sand into said flask and means-'for compressing sand for forming a compact finished molding surface within said flask, and said compressing means being constituted and adapted for displacing some of said sand against said flange for protecting it from damage from molten metal, and means for introducing molten metal into said finished mold.

17. In a centrifugal casting machine, a flask, rotatably supported on the machine, having an open end and adapted to contain asand mold, means supported on the machine positioned for introduction into said flask for forming a sand mold in the flask while the same is rotating, separate means also carried on the machine in position for introduction into said flask for compressing the sand for forming a hard molding surface, means positioned for ,introduction into the flask for pouring molten metal into the mold for forming a casting therein, said flask being adapted to contain said sand mold and said casting and to confine material urged by centrifugal force within said ask, and having a displaceable part adapted to be moved to release said sand mold and casting from the flask.

18. In a casting machine, a flask of sleeve-like form rotatable about its axis and having an open end, said flask being shiftable for disposition of its axis at various angles to a horizontal plane, and said flask having means partially closing the open end and movable away from said end for releasing castings formed in the flask.

19. In a casting machine, a rotatable spindle. a ilask carried by said spindle, a fiuid pressure actuated element in said spindle, a plunger carried by said spindle, so disposed as to be actuated by said uld pressure actuated element and having a head normally at one end of the flask, and adapted to be introduced in to said flask, during rotation of the spindle and flask, by said iiuid actuated element, a source of fluid under pressure connected with said fluid pressure actuated element, said fluid pressure actuated element being disposed in heat transmitting relation with the head so that the fluid in said fluid pressure actuated element will tend to carry away heat absorbed by the head from castings being formed ln the flask.

20. In a centrifugal casting machine, able flask of sleeve-like form and means for forming a sand mold within the flask, and including a shank portion rotatably supported on the machine and having an eccentric axle portion constituting a continuation of said shank portion, a roller journaled on said axle portion, said shank portion and said flask being supported for relative movement for causing insertion of said roller into said sleeve-like mold, and -means for rotating said shank portion for displacing said eccentric axle portion for urging said roller into contact with the sand mold being formed in said flask.

JOHN F. CRAWFORD.

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