US2244490A

US2244490A - Casting machine

Info

Publication number: US2244490A
Authority: US
Inventors: Doyen Daniel
Original assignee: Individual
Current assignee: Individual
Priority date: 1937-12-17
Filing date: 1938-10-27
Publication date: 1941-06-03
Anticipated expiration: 1958-06-03

Description

June' 3, 1941.

D. DoYEN 2,244,490

CASTING MACHINE Filed Oct. 27, 1938 8 Sheets-Sheet 1 xNvENToR DAN/EL DOVE/V June s, 1941. A D. DOYEN' 2,244,490

CASTING MACHINE Filed Oct. 27. 1938 8 Sheets-Sheet 2 INVENTOR DAN/EL DOVE/V June 3, 1941. D. QOYEN 2,244,490 CASTING MACHINE Filed oct. 27, 19:58 8 sheets-sheet s u mvg A NVENTOR m m G3 BY l f l l ORNEYS June 3, 1941.l Q DQYEN CASTING MACHINE l Filed oct. 27, 193s:`

' 8 Sheets-Sheet INVENToR DAN/5L DOYE/V BY Y 'x-QRNEYS June 3, 1941. D. DOYEN 2,244,490

CASTING MACHINE Filed OGt. 27, 1938 8 Sheets-:Sheet 6 Fel. 8

Y I93a,

- INVENTOR DAN/EL DYE/V June 3, 194.1. D. DOYEN CASTING MACHINE Filed oct. 27, i938 8 Sheets-Sheet 7 INVENTR DAN/EL BY DOVE/V RNEYS June 3, 1941. D. DOYEN 2,244,490 CASTING MACHINE,

Filed oct. 27,41938 l f s sheets-sheet a /232 267 in y if Lw? a 23o i *Ill/fl'll V 1115.10 mgm/V Patented June 3, 1941 CASTING MACHINE Daniel Doyen, Brussels, Belgium Application October 27, 1938, Serial No. 237,191 In Belgium December 17, 1937 is claims. (ci. :a2-51') This invention relates to an automatic machine to cast metal parts, more particularly to an automatic machine for casting lead grids for storage battery plates and the like. l

In the past lead grids for storage battery plates have been made by hand-casting, in which a separable mould, adapted for manual opening and closing, was provided, into which the molten metal Was poured by a ladle or dipper. The ladle was filled from 'the surface of the molten metal in a container in which the metal has been heated to the point of liquefaction. This method had the disadvantage that the ladle would pick up oxides of the metal which oated on the, surface, and also. other impurities which are usually found floating on the surface of molten metal.V From the ladle these oxidesand other impurities were poured directly into` the mould which often resulted in imperfect castings.

The hand-casting method was subject to further diniculties, in that the molten metal in the ladle or dipper would cool in the process of being transferred from the container of the molten metal to the mould which often resulted in premature freezing of the metal and caused further imperfect castings. Furthermore, this method of casting could not be carried out with sufcient speed to be economical and the costs of operation were almost prohibitive.

This inconvenience in the handcasting has resulted in the design oflmany diiferent methods and machines to overcome the ditllcultles pointed. out. One type of machine proposed utilized several moulds which were adapted to open and close automatically, and which were mounted on a rotating table, so that they would pass inl succession before a workman who poured the metal into the successive moulds by hand with a ladle filled by dipping from the surface of the molten metal in a container. A part of the operation of A this method was done mechanicallmthat is, the

still allowed the introduction of oxides and lm-z purities into the cast, and, at the same time, did

from being introduced into the mould. This machine was a considerable step forward toward the mechanization of casting work but it solved the problems in only an imperfect manner because it still required a large number of moulds and also presented difficulties arising from a complicated pump mechanism whose output could not be regulated so as to force a predetermined amount of metal to the mould at each operating stroke.

Inasmuch asl the quantity of metal required to iill the moulds is substantially the. same for each casting, it was essential that the pump deliver the same amount of metal each time to the mould.

Furthermore, inlthe prior art, difculties were experienced With the mechanisms furnished to open and close the moulds automatically, inasmuch as rotating cams were usually used for this function. The Vcams were extremely dicult to adjust properly so as to maintain the properv pressure relation between the halves of the sep l arable mould and frequently the mould halves were not properly engaged and a gap would appear between them which would spoil the casting' made under these conditions because large seams would be formed on the casting where the molten metal had been dissipated in the gap between the mould halves. I

To avoid the difliculties of the machines of the prior art, described above, thepresent invention contemplates an automatic machine for casting relation with other operations which prevents the formation of gaps between the halves of the not overcome the dililculty presented by the cooling of the metal in the ladle in its transference from the container to the mould.

-To obviate these diillculties it was next proposed to provide a mechanical pumprin the cori` tainer for the molten metal which would force the molten metal directly from the container moulds by maintaining a constant pressure tending to thrust the halves of the moulds into cooperation. I Y This invention contemplates the provision of a mechanism for opening and Vclosing the mouldV automatically vand the provision of A means for pumping the 1moltenmetal from a point below its free surface in the .container to the mould by placing fluid pressure on a portion of its free surface. In a preferred form of the invention, the fluid pressure is impressed directly upon the surface of the molten metalrin a confined area which is segregated from the rest of the molten metal by the pumping means. A timed relation is maintained between the movements of the mould halves and the application of uid pressure in the pump means.A The segregation of a portion of the free surface has the advantagethat it dispenses with the necessity of providing a. uidtight cover for the whole top of the container.

To overcome the difficulties arising from the cooling of molten metal during the interval in which it is being transferred from the container to the mould, the body of the pumping means, mentioned above, may be positioned Within the container, so that it will be surrounded by the molten metal with which it is in communication by means of a one-way valve which automatically closes when fluid pressure is being exerted upon the surface of the segregated metal in the pumping means. The invention also contemplates the provision of a one-way valve cooperating with the pump means which may be mechanically controlled in timed relation with the action of the fluid pressure.

The invention further contemplates the provision of a mechanism in which a pumping means cooperates with a control mechanism, which assures that the conditions under which the pumping means is operating will be such that the pumping means will deliver at each actuation, a predetermined amount of molten metal to the mould. This control mechanism is preferably responsive to a function of the level of the molten metal in the container, and arranged so that the above mentioned purposes are obtained autoy matically at all times during which the pumping means is operating. A float may be placed in the container to cooperate with the free level of the molten metal to obtain this result, the float being adapted to cooperate with a-system of auxiliary apparatus to control the functions of the pumping means.

The cooling of the molten metal during transference in the feed line between the pump and the mould is prevented by placing the feed line in the molten metal in the container so that the temperature'of the feed line will be substantially that of the molten metal, thereby substantially preventing any cooling of the metal even though it passes out above the maximum level of the molten metal in the container The relatively shortportion of the feed line which is located above the free surface of the molten metal in the container will still have a 'sufficiently high temperature to prevent freezing of the molten metal.

Other objects and advantages of this invention relating to the arrangement, operation and function of the related elements of the structure, to various details of construction, to combinations of parts and to economies of manufacture, will be apparent to those sk lled in the art upon consideration of the following description and appended claims, reference being had to the accompanying drawings forming a part of this specication wherein like reference characters designate corresponding parts in the several views.

Figure 1 is an elevational view of amachine embodying one Iform of the invention.

Figure 2 is a plan View of the machine illustrated in Figure 1.

Figure 3 is an enlarged schematic diagram of 1 the control and distribution system vfor the fluid tribution system'for the uid pressure system controlling the movements of mould portions.

Figure 5 is a sectional elevationof a detail of the distributor means shown in Figure 4.

Figure 6 is a longitudinal section of the distributor means shown in Figures 4 and 5, taken along line 6-6 of Figure 5.

Figure 7 is an enlarged schematic diagram illus- 'trating a variation of the control and distribution system for the fluid pressure illustrated in Figure 3..

Figure 8 is an enlarged schematic diagram of another variation of the control and distribution system for the uid pressure as illustrated in Figure 3.

Figures 9 and 10 are schematic'diagrams illustrating another variation of the control and distribution system for the fluid pressure as illustrated in Figure 3.

Modifications illustrated in Figures 1 to 6 Referring to Figure 1 of the drawings. a base member I5 is provided which is preferably made of cast iron to which are attached upright mem- 'bers I6 and vII which may be of any convenient pot I9, being lined with refractory material 2 la to form a re pot about the melting pot into which gas burners 22 or the like are adapted to project names to maintain the temperature of the melting pot to a desired degree, and upper section 23 being adapted to be tted over the lower section 2l to cover the melting pot I9. To prevent the accumulation of undesired gases in the furnace,

vents

24 and 25 are provided to cooperate with a chimney 26 which is adapted to draw the gases from both portions of the furnace. The burners 22 are provided with control valves 21 to regulate the amount of gas burned in the lower portion of the furnace about the melting pot I9. The valves 21 may be connected to a common supply pipe pressure controlling the pump mechanism eject- 28 which is in communication with a source of inflammable gas (not indicated).

Positioned on the interior of the melting pot I9, a pumping means 29 is provided which is shown in phantom in Figure l. The pumping means is provided with a spout 30 which cooperates with an inlet of a mould 3I, which is divided into two portions, a xed portion 32, flxedly attached to the frame upright I6, and a movable portion 33, attached to guide members 34. The guide members are adapted to slide along guide rods 35 mounted in position between the main uprights IB and Il.

In order. to move the guide members SII along the guide rods 35, a uid pressure actuated cylinder 36 is provided which is attached to the frame member II adjacent the left side (Figure 1) of the frame I5. On the interior of the cylinder, a piston 37 (Figure 4) is provided to drive a stem 3B, which is attached to the end ofthe guide members 34 by Ameans of a universal joint 39. The joint 39 compensates for minor discrepancies in alignment between the mould portions as the guide members 34 move along the guide rods 35 under the influence frame member I1.

` position with the shaft 56.

upon shaft l), which is journaled in bearings 5I suitably mounted on the frame member I5 relatively near the center thereof. The shaft 50 is mounted transversely of the frame member I 5 as is clearly shown in Figure 2, and adjacent its center portion is supplied with a cylindrical enlargement 52 which extends a substantial distance between the bearings 5I on the shaft 50. A wide web 53, which is cut away at the extreme left end in Figure 1, is adapted to cooperate with the cylindrical enlargement 52 to form an apron upon which cast articles are carried away to any desiredposition to the left of the machine. The cast articles are deposited upon the web 53 through the medium of a conveyor 54 mounted on the frame member at a point below the mould 3l to catch the ejected castings from the mould. The ejected castings ride down the conveyor 54 under the influence of gravity until they are deposited on the surface of the web 53, thence being carried to the desired location.

A mechanism is provided to cooperate with the movable portion 33 of the .mould to eject the finished castings formed'in the mould after completion of a casting operation. The movable portion. of the mold is provided with small undercuts to hold the casting in position upon separation from the fixed portion 32 of the mould. Bosses 56 are provided on the rear faceof the movable portion of the mould to house ejector pins 51V which cooperate with the castingto thrust the completedcasting from the movable portion of the mould when the ejector pins 51 cooperate with a plate 56 mounted on rods 59 firmly fixed in theV This holds the plate 56 in Y proper position to contact. the ejector pins 51 when the movable portion ofthe mould has been moved to the left (Figure 1) under the influence of the stem 38. When the completed casting is ejected through the action of the pins 51, it falls upon the conveyor 54 and moves to the web 53 as described hereinbefore.

Returning to the shaft 50, the forward end thereof (Figure 1) is provided with a sprocket 69, keyed to the shaft 50 in the well known manner,

which cooperates with a chain 6I, engaging another sprocket 62 keyed to a shaft 63 also mounted transversely on the frame I5 in Aparallel juxta- The shaft 63 has keyed thereto at intermediate positions cam members 64 (Figure 3) and 65 and at a point adjacent its end, a rotor memberv 66 of a fluid pressure distributor 61. the purposes ofiwhich are to. V be described hereinafter.

From a source of fluidv ressure (not shown);

yconduits 11 and 18, Whchconduits lead uid to the opposite ends of the cylinder 36 to control the movements of the piston 31 for opening and closf ing the mould 3I in timed relation with other functions during the casting cycle. The conduit 11 is in communication. with the left end (Figure 4) of the cylinder 36 and may be utilized at selected times to' thrust the movable portion 33 of A the mould 3I by iuid pressure through the agency of the piston 31 into cooperation with the fixed portion 32 of the. mould during the pouring period of the casting cycle. .The conduit 18 is in communication with the right or forward end of the cylinder 36 and fluid pressure may be utilized at selected times to thrust the movable portion 33 of the mould 3| out of cooperation with the fixed portion 32. During the periods in which the fluid under pressure flows through the conduit 11, the opposite end of the cylinder 36 is vented to the atmosphere by the conduit 18 (Figure 4) through the medium of the indentations 16 cooperating with the conduit 19. Conduit 19 is provided with a hand valve which, in turn, cooperates with a conduit 6l which is vented to the atmosphere.

keyed to the shaft 63 as already described. The

rotor 66 may be of frusto-conical construction and adapted to fit into a housing 66a having a` conical depression to cooperate closely with the side of the frusto-conical rotor member 66 to form a gas-tight connection between them. To hold the rotor member in close engagement with the housing 66a, a stem 63a is provided vwhich projects forwardlyV from the shaft 63 through a central` aperture 66h in the housing 66a; the outer end of the projection 63a is threaded and provided with lock nuts 63h which may be utilized to thrust a pair of .washers 66e and 66d against the housing 66a through the medium of a coil springepand thereby pull the rotor and the housing together. To reduce the frictionbbetween the collar 66d.'and the housing 66a, an anti- -friction means' 66)e is provided to act between a conduit 16 leads fiuid (underpressure)V to a conduit 13 leading to a second hand valve 14 and them. Thehousing 66a may be held in stationary position bybeinganchored against a portion Ila of the frame, the conduits 15, 11, 18 and 19 aiding in holding the housing in position.

As pointed lout above, the rotor 66 is provided with indentations on the frusto-conical peripheral surface, which are utilized to place' in communication atV 'selected' times the conduits 11 and 18 with conduits 15 and 19. Figure 4 shows the position iny ,whichfthe left end of the cylinder 36 isA in communication with the source of fluid pres` sure as introduced into the distributor by means ofthe conduit 15, which is in communication with indentation 16a and vconduit 11. figure, the forward or right end of the cylinder 31 is vented 'to the atmosphere by being placedin communication with the conduit 19 through the agency ofconduit 18 andv the indentationA 16. I0

YWith the parts 'in position as shown in Figure 4,

Y thepis'ton 31is capable of placing the movable thence by a conduit 15 to the uid pressure'dis-v 16 and 16a (Figures 4 and 5) in the rotor 66 portion 433 of the mould into close cooperative re- ,bel described hereinafter.

In the same lation-.With the fixed Vportion 32, at which time mlten'leadsintroduced' into the mould as will C Turning to Figure 5, a second position of the distributor 61 is shown in which the conduit 18 and the forward end of the cylinder 36 are placed in communication with the conduit 15 through the agency of the indentation 16 to direct the fluid pressure into the forward end of the cylinder to enable the piston 31 to move the movable portion of the mould 3| from its cooperative relation with the fixed portion 32. At the same time, the

conduit 11 and the left end of the cylinder 36 are placed in cooperative relation with the conduit 19 to be vented to the atmosphere and allow the fluid entrapped in the cylinder to escape upon movement of the piston 31.

The indentations 16 and 16a are provided with displacedportions 16h and 16e which are connected to the principal branch by means of lat-v eral passages 16d and 16e. The lateral passages 16d and 16e may be parallel to the longitudinal axis of the shaft 63 as shown in Figure 6. Figure 6 also shows the displacement ofthe portion 16e from the principal branch 16a and also the displacement between the principal branch 16 and the lateral branch 16b. The rotor 66 is constant- `1y rotated through the agency of the shaft 63 to which it is keyed and the relation of the lengths of the indentations 16, 16a, 16h and 16o with reference to the conduits 15, 11, 18 and 19 are such that a timed relation may be obtained between the different portions of the casting cycle having reference particularly to the operation of the piston 31 and the

cams

64 and 6 5 (Figure 3) which are also keyed to the shaft 631.

Returning again to the accumulator 12, a second conduit 82 leads therefrom to a pressure regulator 03 which is adapted to lower the pressure as measured by a gauge 84. From the regulator 63, a conduit 85 leads the fluid pressure to a second accumulator 86, and from thence it is led by means of conduit 81 to a hand'valve 82B. From the hand valve 88, a c'onduit 89 leads the fluid pressure toa normally closed valve 90 (shown in detail in Figure 3) under control of cam 64 mounted upon the rotating shaft 63. The hump of the cam 64 cooperates with a lever 9| through the medium of an adjustable rider 9|a. The arm 9| is pivoted on pin 92, journaled in a projectiort 93 on the casing of the valve 90 and cooperates with a central pin 94 to thrust the same downwardly against a spring member 95 to re' move the valve member 96 from its seat to open the valve. The action of the spring 95 is sufficient to close the valve after the hump of the cam 64 has passed its cooperative position with the lever 9|.

The actuation of the valve 90 allows the fluid pressure to flow into conduit 91 which is in communication witha second normally open valve 90 of somewhat similar construction as valve 90, being normally held open by a spring 93a. An arm 99 through an adjustable rider 99a is adapted to cooperate with the hump of the cam 65 also mounted upon the rotating shaft 63, whereby the cam 65 is adapted to close the valve 98 in timed relation with the opening of the valve 90. The timed relation is preferably such that when the valve 90 is open, the valve 98 is closed. These valves are both in communication with the pump means 29, preferably adjacent its upper end, by means of conduit 91, and control to a certain degree the flow of fluid pressure to and from the pump means.

The pump means 29 vis in the nature of an elongated cylinder |00, preferably made of metal not attacked by the molten metal. It may be positioned in a vertical position in the molten metal M of the melting pot I9, and adjacent its upper end, it is provided with an outwardly .eX- 'tending flange |0| to which is attached a closure plate |02 in any well known manner. Adjacent its lower end, the cylinder |00 is provided with a one-way valve |03 which may be of any well known construction being designed to allow the molten metal to flow through the valve |03 into the interior of the cylinder to maintain the level of the molten metal on the interior of the cylinder substantially the same as that found in the container I9. The cylinder |00 is also provided at its lower end with an outlet tube |04 which forms a-t its'upper end the spout 30 being provided with a downwardly extending tube |05 which is positioned immediately above the pouring inlet of the-mould 3|. For convenience in cleaning, the outlet pipe |04 and the tube |05 are provided with an outwardly extending flange |06 to which is bolted a plate |01 in the nature of the closure member.

If preferred, the interior ofthe cylinder |00 is provided with a floating separation plate |06 which is carried by the surface of the molten metal. The plate |08 is especially useful when a fluid is used in the fluid pressure systemwhich is chemically active with the molten metal because the plate separates the molten metal from the fluid so as to prevent any reaction between them. By the use of a fluid pressure acting directly on the surface of the molten metal, or by valve ||1.

the nterdeposition of the plate |08, it is possible to use fluid pressure from one source to actuate both the actuating cylinder for the mould and the means to force the molten metal to the mould.

Referring to Figure 3 of the drawings, a mechanism is disclosed which controls the quantity` of fluid pressure impressed upon the surface of the molten metal inside of the cylinder |00 to -force the molten metal to the spout 30, there is a relation between the height of the metal and the amount of pressure required which may be correlated to deliver a uniforni 'quantity of metal to the spout, so that the mould may be exactly filled during each pouring period. This invention contemplates the provision of a, mechanism `which correlates the level of the molten metal in the container |9 and the fluid pressure maintained in the conduit 91 to actuatethe pumping means 29 to attain the result mentioned.

For this purpose, a float ||0 cooperating'withl the surface of the molten metal is provided which is connected by a line or cord to a rack bar- |I2 and a weight H3. The' line cooperates with the float ||0 and the rack ||2 over pulleys H4 which alle conveniently located to reduce resistance of movement of the line to a minimum. The rack l2 is supported by suitable guides (not shown) to cooperate with a pinion 5 which is attached to the spindle ||6 of a changes in level of the molten metal, the rack ||2 will move in response thereto, so that the pinion I I5 will change the position of the closure As theV float I|0 moves in response to element of the valve ||1, so that the valve will constrict or open the aperture through which gas may be flowing from conduit ||8 to conduit H9.` The conduit I|8 is in communication with the conduit 91, described above, and the conduit ||9 is in communication with conduit |20 which is preferably vented to the atmosphere having communication with the outlet side of valve 98 by means of conduit 98h. A second valve |2l, adapted for manual manipulation, is in communication with conduit |20 by conduit |22 and with conduit 91 by conduit 123, so as to be in parallel with the valve ||1.

By this mechanism the amount of fluid pressure in the conduit 91 which actuates the pumpable portion 33 moves to an extreme open posiing means 29 may be controlled by the valves ||1 and |2| in such a manner as to have a relation to the height of the molten metal in the container |9. As the level of the molten metal recedes in the container I9, the valve ||1 will be 'closed to a corresponding extent to raise the pressure in the conduit 91 in some relation corresponding to the change in level of the molten metal, so that the spout 30 will deliver a substantially constant amount of molten metal to the mould.A

The shaft 63, carrying

cams

64 and 65 and the rotor 66 of the distributor 61, controls the sequential operation of the elements of the casting machine. As shown in Figure 3, the

cams

64 and 65 are mounted in the same angular relation with respect to the shaft 63, so that when the hump of the cam 64 cooperates with the arm 9| of the valve 90, the hump of the cam 65 is simultaneously cooperating with the arm 99 `of the valve 98. In this manner, the two valves are actuatedsimultaneously, so that` when the valve 90 is opened, the valve 98 will be closed to allow the building up of a proper fluid pressure in the conduit 91 to force the molten metal from the spout 30 through the agency of the pump 29.

During the s ame time interval, the rotor 66 will-be positioned to supply fluid pressure to the left end of the cylinder 36 and venting the opposite end to the atmosphere (Figure 4), so that the movable portion of the mould will be held in cooperative relation with the fixed portion 32. It is essential that the mould is tightly closed with the two mould portions in close cooperative relation to prevent leaks during the period in which `the fluid pressure is acting in the pump 29 to force the molten metal through the spout 30 into the mould for the pouring operation. As the humps of the

cams

64 and 65 rotate and cease to cooperate with the arms 9| and 99 of the

valves

90 and 98 respectively, the valves will again move to their normal positions, that is, the valveI 90y will be closed by the action of its spring 95 and the valve 98 will be opened by the action of its spring 98a. This will release the fluid pressure from the surface of the molten metalin the pump 29 to terminate the pouring period and allow the valve |03 to `open to equalize the levers of the molten metal on the outside and the inside of the pump and in readiness for another cycle.

During this time interval, the rotor 66 of the distributor 61 will have moved substantially to the position shown in Figure 5, in which the fluid pressure is`led to the forward or right end of the cylinder 36 and the left end will be vented to the atmosphere. Under these circumstances, the fluid pressure flowing in conduit 18 will act against thepiston 31 to move the movable portion 33 of the mould to open the same and allow the removal of the completed casting. The comtion. The force of gravity will cause the ejected castings to fall on conveyor 54 which guides them by a sliding action to the moving apron 53, which conveys the castings to a desired position to the left of the machine (Figure 1).

Upon ejection of the castings from the mould, the distributor rotor 66 will have moved to a new position to inaugurate a new cycle.

Modification illustrated in Fig. 7

In Figure 7, a modification of the casting machine is shown in which fluid pressuretc actuate the pump means 29 is segregated from the fluid pressure employed to actuate the cylinder 36 which acts to open and close the mould. In this form of the invention, the shaft 63 is again furnish'ed with

cams

64 and 65 which control valves and 98 and also distributor 61 which controls the ow of fluid pressure to the cylinder 36 in a manner similar to the modification illustrated in Figures lto 6. The fluid pressure actuating the pump 29 in the modification illustrated in Figure 7 is conducted from the

valves

upper end of the threaded rod |43 is provided` with a hand wheell |43a, so that the rod may be suitably'adjusted by manual manipulation in itsv relation to plates |39 and |49.

The cylinder |3| is in communication with the pump means 29 through conduit |55 which cooperates with the pump means 29 adjacent its upper end and with the cylinder |3| through an aperture |56 in the cylinder end plate |42. Avv lateral extension |51 is provided for the conduit |55 which terminates in a one-Way valve |50 which may be of a spring pressedball type if preferred and is adapted to close by iiuid pressure formed in the conduit |55 and opens to the atmosphere when the pressure in the conduit |55 is sub-atmospheric. The action of the valve |58 is adapted to maintain the pressure in the conduit |55 at substantially atmospheric pressure when the piston |32 is in the optimum retracted position under the influence of spring |34.

In this modification, the fluid pressure, active in the chamber of the cylinder |3| adjacent plate |42 by the piston |32, is used' to force molten metal from the pump means 29 positioned in the molten metal container I9 to the moulds (not shown). y Inasmuch as the pressure in this chamber is maintained at atmospheric pressure when the piston |32 is in retracted position, it is clear that the length of the stroke of piston |32 in cylinder |3| controls the quantity of fluid supplied to the pump means 29 and, therefore, is related to the fluid pressure developed. The rod |43 being threaded adjacent its distal end, and provided with an enlargement |44 at its proximate end, a mechanism is provided which allows the rod |43 to be adjusted longitudinally, so that the point of cooperation between the enlargement |44- with the enlargement |35 on the piston rod |33 may be controlled to adjust the length of the stroke of the piston |32 and thereby control the iiuid pressure available to actuate the pump means 29.

The enlargement |44 on the threaded rod |43 acts as a stop for the piston rod |33 by abutting against the adjustable enlargement |35 as shown in Figure 7. An initial adjustment of these members is obtained by manual manipulation of the parts in which the threaded rods may iirst be loosened so as to draw plates |48 and |49 together and remove the locking relation between them andthe rod |43, so that the rod |43 may be by means of hand wheel |43a rotated to change its longitudinal relations. With the members in loosened position, the relation between the longitudinal position of the rod |43, plate |49, and pinion |45 may be determined by experiment to obtain the desired piston stroke, after which the threaded rods |5| are again tightened by manual manipulation to x the relation of the members in the desired adjustment. As the screws |5I are tightened, the plates |48 and |49 tend to be forced apart so as to lock the plates to the threaded portion of the rod |43 by a cramping action ln the threaded portions. When an adjustment is obtained, the position of the enlargement |44 has been determined to control the stroke of the piston |32 and, in turn, control the iiuid pressure available to actuate the pump means 29. As the enlargement |441 is moved a greater distance from the plate |42, the piston |32 must traverse a greater distance because engagement of enlargement I35on the end of piston rod |33 with the enlargement |44 on the end of the threaded rod |43 limits the stroke.

The relative position of the enlargement |44 on the rod |43 is further controlled automatically by a mechanism which cooperates with the pinion |45 in a manner similar to that already described with reference to the embodiment illustrated in Figures l to 6. In the present modication, the fluid pressure acting on the surface'of the molten metal in the container I9 is also controlled'by a. function which is responsive to changes of level in the molten metal. For this purpose, -iloat ||0 is provided to cooperate with the free surface of the molten metal in the container, the iioat acting through line to move a rack |59 supported by guides |60 in cooperative relation with pinion I45. A counterweight |6| is provided to keep tension in line and to effectuate further the movements of the oat |I0. As the iioat ||0 raises or lowers in response to changes in levelof the molten metal, the rack |59 changes its position correspondingly to rotate the pinion |45. The pinion |45, being in threaded relation with the rod |43, raises or lowers the rod in response to changes in level of the liquid and thereby changes the relation between the enlargement |44 and the plate |42.

This relation controls the length of the stroke of the piston 32 and thereby controls the fluid pressure acting in the pump means 29.

As already described, the amount of the fluid by a function of the change of the level of th molten metal in the container I9 to change the stroke `of the piston |32 so as to maintain the quantity of molten metal supplied to the mould substantially uniform. Upon release of the uid pressure in the conduit |30, by the release of

valves

90 and 98 through the action of the humps of

thev cams

64 and 65, spring |34 pushes the piston |32 toits initial optimum retracted position and all of the parts of the fluid pressure system are at substantially atmospheric pressure and ready for another cycle, 'I'he timed rela- -tions between

cams

64 and 65 and the distributor rotor 56 are similar in this modication to that already described with relation to the modification illustrated in Figures 1 to 6. The mechanism for controlling the movements of the mould are also similar to -those already described and no further description will be necessary.

Modification illustrated in Figure 8 In this modification of the invention a mechanism is provided in which iiuid pressure utilized to actuate the pump means 29 in the molten metal container |9 is supplied by evaporation of a,volati1e liquid at the relatively high temperature of the molten metal. A small amount of the volatile liquid, preferably anamount capable of being metered, is supplied at desiredv times to the pump means 29 by a secondary pump means |10, actuated by aneccentric |1I, which is adjustably positioned on shaft 63 by cooperating with an inner eccentric Illa. The pump means |10 is in communication with a source of liquid (not indicated) and with a chamber |12 on the pump means 29 by conduit |73, these connections to be described in detail hereinafter.

Upon evaporation of the volatile liquid in the pump means 29, a fluid pressure is generated in the cylinder |00 which ejects molten metal from the spout 30 into the mould (not shown). This motivating fluid pressure is controlledby a system of valves in a manner similar to that already described with reference to Figures 1 to 7, the

To attain these ends, the closure plate for the cylinder of the pump means 29 is provided with a valve chamber |12 which is in communication with the cylinder |00 and with conduit |13. The flow of4 fiuid from the cylinder |00 to the conduit |13 is prevented by a spring-pressed ball valve |14 which is, however, responsive to pressure in conduit |13 to allow epntry of liquid into the chamber |12 where it is evaporated under the influence of the high temperature to form the fluid pressure already mentioned.

The conduit |13 is in communication with a second valve chamber |15 which is in direct communication with pump by means of conduit |10. The chamber controls the flow of liquid from a source (not indicated) to the pump means |10 and also the flow of liquid from the pump means |10 to the evaporating chamber |12. For this purpose, a pair of spring-pressed ball valves are provided. The first valve |11, which is responsive to pressure in the chamber |15, allows liquid to now from the pump means |10 to the vevaporating chamber |12 through the medium of the conduit |13 and the second valve |18 which is responsive to suction in the chamber |15 and allows liquid to flow from the source (not indicated) through conduit |19 to the pump means |10.v During the compression stroke of the pump means |10, the valve |18 will be closed, while the valve |11 will open to allow the passage of liquid as already described, while during the suction stroke of the pump |10, the valve |11 will be closed, and the valve |18 will open to allow entry of liquid. A

The pump means |10 may be of any convenient construction and is preferably provided with a casing |80, in'which a piston |8I is fitted to Ireciprocate under the influence of a connecting rod |82 terminating in a rider |83 cooperating with the hump of the eccentric |1| on the shaft 63. The hump of the eccentric |1| thrusts the piston |8| into the casing |80 to create the pressure necessary to displace the liquid into the the evaporating chamber |12. After the hump of the cam has ceased cooperating with the rider |83, a spring |84 is provided which acts between a stationary plate |85, supported in spaced relation from body |80 by means of bolts |86, and a collar |81, positioned o n the connecting rod |82. The action of the spring |84 returns the rider |83 into the path of the hump of the cam |1| for a new actuation. Guiding means |88 are provided to cooperate with the connecting rod |82 to supp ort the rider |83 during the period in which it is in cooperative relationrwith-the hump of the cam In order to control the amount of fiuid pressure formed in the cylinder |00 of the pump means 29, a second conduit |90 is provided which is in communication with the upper end of the cylinder |00. The conduit |90 is in communication with valve 98 which serves a purpose similar to that already described. with reference to Figures 3 and 7. Cam 65, which actuates the valve 98 through the medium of lever 99, is. placed in an angular relation with reference to shaft 63 and cam |1| to obtain substantial simultaneous actuation of valve 98 and pump means |10. In this manner, the valve 98 is closed at the time the pump means |10 injects liquid into the evaporating chamber |12 to supply motivating fluid pressure to eject the moltenmetal from the spout by-pass `|93 is provided, in which is positioned valve |94 which is provided with a control pinion |95 actuated by a rack |98. The movements ci the rack |96 are controlledby float H0 through the medium of line- I cooperating with a counter-weight |91 to further effectuate the movements of the fioat. The action of the valve |94 is similar to the action of valve ||1 in Figure 3. The fluid pressure acting in the cylinder 00 is controlled in this manner by a function of the level of the molten metal in the container |9, which, in both cases, is obtained by the interaction of the oat ||0 and the rack |96, the valve |94, and the counter-weight |91.

The vaporof the evaporated iiuid may be allowed to escape to the atmosphere if desired by means of conduit |93a, or if found economical it may be condensed and used again. A condenser C (Fig. 1) may be provided for this purpose from which the pressure is relieved in the well known manner.

The furnace for supplying the heat to the container I9 in the various modifications may be regulated by an automatic valve |98 which controls the -low of combustible fuel to the burners 22. The valve |98 may be of the solenoid-controlled type and is regulated by the-temperature responsive means |99, positioned in the body of the molten metal. Any convenient regulating system may be utilized for this purpose, as long as automatic valve |98 supplies combustible material to the burners at a rate exactly sufficient to maintain the temperature of the molten metal Within prescribed limits.

The action of the pump means 29, except as described above, is substantially similar to that described in Figure 3, and need not be described in further detail. Other elements of the machine controlled by the shaft 63, particularly the fluid pressure means controlled by the regulator B1, cooperate with the pump means 29 in a manner similar to that already described in the other modifications.

Modifications illustrated in Figs. 9 and 10 In the modifications illustrated in Figures 9 and 10, the pump means for ejecting the molten metal from the container |9, into the mould 3| is actuated by fluid pressure means which thrusts a plunger downwardly into a Acylinder to force the molten metal from spout 30 as counter-distinguished from'the previously described modifications in which fluid pressure acted directly upon the surface of the molten metal in the pump means 29. In the modification illustrated in Figure 10, an automatic control means is provided to vary the length of the stroke of the plunger in the pump cylinder in accordance with a function of the change of level of the molten metal in the container so as to assure the deliverance of a constant quantity of molten metal to the mould at each actuation of the pump.

Referring to Figure 9, a submerged cylinder 200 is provided having a one-way inlet valve 20| acting in a manner similar to the one-Way valves already described with reference to previous modifications. A spout means 30' is provided to cooperate .with the lower end of the cylinder 200.

The upper end of the cylinder 200 is closed by an apertured plate 202,v attached to the cylinder in any convenient manner, through which a cylindrical plunger'203 is adapted to reciprocatey preferably made of the metalwhich is stable at high operating temperatures and chemically nonreactive with the molten metal M in the container.

Attached to the upper end of the plunger 203 by bolts 204, a connecting rod 205 is provided which is insulated from the plunger 203 by an insulating plate 206. Bolts 204 are also provided with insulating bushings 201 to prevent heat transfer from the plunger 203 to the connecting rod. A piston 208 is attached to the upper end of the connecting rod 205 and is adapted to cooperate with an actuating cylinder 209, held in fixed position in any convenient manner (not indicated). Piston 208 is provided on its upper side with gasket 2|0 to forman expansion chamber in which iiuid pressure is adapted to thrust the piston 208 downwardly and thereby actuate the plunger 203 in the submerged cylinder 200. The lower end of the cylinder 209 is provided with aclosure plate 2|| which vents the lower chamber to the atmosphere by means of apertures 2|2 and supports a central bushing 2|3 to guide the longitudinal movement of the connecting vrod 205. Projecting downwardly from the lower end of the cylinder, threaded rods 2|4 are provided which are attached to the closure plate 2li by a supporting plate 2|5 and are held in spaced relation at their lower ends by plate 2|6. The plate 2|6-is provided with a central anti-friction bushing 2|1 to further guide the connecting rod 205 .in its longitudinal movement. To prevent rotation of the connecting rod 205, a longitudinal slot 2|3 is provided therein to cooperate with a key 2|9, preferably fixed in bushing 2|1 anchored inlplat 2|6. F

To thrust the piston 208 and the plunger 203v upwardly after release of the fluid pressure in the chamber above the piston, a spring 220 is provided which preferably embraces the connecting rod 205 and acts between a seat 22l on plate 2|6 and a second plate 222 attached adjacent a central position to the connecting rod 205 by abutting against a shoulder 223 formed on the connecting rod. The downward stroke of the piston 208 and the plunger 203 is controlled by threaded collars 225, positioned upon the threaded portion of rods 2|4 which form an abutment for plate 222 which is attached to the connecting rod 205. The collars 225 are adapted for manual adjustment to control the length of the stroke ofthe piston and plunger.

The chamber formed above the piston 203 is in communication with a source of fluid pressure by conduit 226 which is fixed in cylinder head 221 and leads to

valves

90 and 90.

Valves

90 and 98 have been described hereinbefore and their function in this modification is similar to that already described. Valve 90' is controlled by cam 64 through the agency of arm` 9|, cam 64 being attached to shaft 63. In a similar manhner, Valve 98 is controlled by cam 65 which is also attached to shaft 63 through the medium of arm '99. The action'of the

cams

64 and 65, by the rotation of the shaft 63, admit and release fluid pressure in the chamber of the cylinder 209 at selected times to control the movemerts of the plunger 203 in'timed relation with the movements of the movable mould portion as has already been described with reference to the other modifications. f

Referring to Figure 10, a submerged pump cylinder 230 is provided having the same type of one-way valve and spoutmeans as before described with reference to other modications. The

upper end of the cylinder 230 is open and a relatively short plunger 23| is provided to reciprocate in the cylinder to 'force the molten metal from the spout 30 to the mould 3|.

The plunger 23| is driven by an articulated connecting rod 232 which extends through an aperture 233 formed in cover 234 of the furnace.

The articulated connecting rod is formed with ,a universal joint adjacent its central portion which consists of plates 235 clamped on a head 236 formed on the end of the one portion of the connecting rod 232 with heat insulating material 231 juxtaposed between the parts. The clamping action is attained by bolts 238 threading through proper apertures in plates 235. One plate 235 is provided with a socket 239 to cooperate with a spherical head 240 formed on a part of the connecting rod 232. The upper end of the connecting rod 232 is connected with a piston 24| which is adapted to reciprocate in a cylinder 202, held in fixed relation with the cylinder 230 by means of bolts 243 fixedly attached to the cover 234 of the furnace. The lower end of the cylinder 242 is provided with a perforated plate 240 which vents the lower portion of the cylinder to the atmosphere and is provided with a central` central bushing 24B is also provided with a projection 249 which registers with a longitudinal slot cut in the connecting rod 232 so as to prevent rotation of the connecting rod with respect to the rods 243.

Th'. plate 206 forms a seat for one end of a spring 250 which preferably embraces the connecting rod to thrust the piston 24| and the plunger 23| upwardly after it has been actuated by fluid pressure in the cylinder 242. The spring A250 also engages a plate 25| adjacent its other end, the plate having a central aperture cooperating with the connecting rod 232 and abutting against a stop 253 flxedly positioned on the connecting rod 232. 'I'he spring 250 pushes upwardlypn the plate 25| which is provided with apertures 252 to ride along the rods 243 to abut against the collar or stop 253, which transmits the upward thrust to the piston 24| and brings the piston with the plunger 23| to an initial position upon release of fluid pressure in the cylinder.

The plate 25| is also provided with outwardly extending portions beyond the rods 243 which portions are provided with apertures 254 to cooperate with depending rods 255 which have on their lower ends enlarged heads 256. The depending rods 255 are supported by a plate 251 which is positioned above the head of the cylinder 242. 'Ihe plate 251 is provided with a centrally-located threaded aperture 253 through which extends a threaded rod 259, rotatably journaled at its lower end in an aperture 260 formed in the head of the cylinder. A beveled pinion 26| is keyed to the threaded rod 259 adjacent its journal and is adapted to cooperate with a beveled gear 262,4 keyed to a horizontal shaft `263, which is journaled in brackets 264 attached to the upper end of the cylinder. The shaft 263 has a sprocket 265 keyed thereto which is adapted to cooperate with the bight of a chain 266 whose depending ends are attached to-the iloat 261 by line 266 and to counter-weight 268 by line 21o. v f

The oat as illustrated cooperates with the surface of the molten metal in the container I8 and as the level varies, the iloat will move in correspondence thereto which enables the tloat in cooperation with the counter-weight 269 to move the chain 2&6 with reference to the sprocket 265 to cause a rotation oi' shaft 263 which, in turn, rotates the beveled gear 282.' the beveled pinion 26B, and the threaded rod 259. Rotation oi the threaded rod 259 changes the position of the plate 251 by displacing the plate longi-I tudinally of the rod 359, so that the heads 258 of the depending rods 265 change their relation `with the plate 25l. The relation between the4 plate tt and the heads 256 determine the stroke i the piston 2M and thereby controls the stroke of the plunger 23! in the submerged pump in the furnace. In this manner, the stroke of the plunger 28| may be controlled by some function oi the change oi level of the molten metal in the container it, so that a predetermined amount oi molten metal may be ejected from the spout it into the mold 3l.

Fluid pressure is led to the cylinder lil by means of the conduit 225 in a. manner similar to that described with reference to Figure 9, and

t is controlled by valves lio and 93. The timed re= lation between the pump means in the molten metal container and the nuid pressure means actuating the moulds remains substantially the same in this modification as in those already described.

it is to be understood that the above detailed description oi the present invention is intended to disclose an embodiment thereof to those skilled in the art, but that the invention is not to be construed as limited in its application to the de tails of construction and arrangement of parts illustrated in the accompanying drawings, since the invention is capable of boina practiced and carried out in various ways without departing from the spirit of the invention. rilhe used in the specincation relating to the operation and iunction o the elements oi the inventlon is employed for purposes of description and not oi limitation, and it is not intended to limit the scope of the following claims beyond the requirements of the prior art.

What is claimed is: i

l. in a device oi the class described, separable moulds, a container for molten metal, means to leed the molten metal from the container to the moulds, duid pressure means to force the molten metal from the container into the conveyor means to feed the molten metal to the moulds, and means responsive to changes oi the level of the molten metal to vary the duid pressure in proportion to said changes whereby a predetermined amount oi molten metal Vis ied to the moulds through the conveyor means.

2. ln a device of the class described, a container for molten metal, separable moulds, conveyor means to carry molten metal irom thev in level of the molten metal in the container,

to the moulds. at selected times, valve means co` operating with the pump means to place the' pump means in communication with the molten 4metal at selected times, a source of iluld pressure, and control means acting between the source of fluid pressure and the pump meansn to allow the iluid pressure to actuate the pump means in timed relation with the operation oi said moulds, and means responsive to variations to determine the amount of -fluid pressure ap plied tothe pump means to maintain the quan tity of molten metal forced to the moulds substantially uniform.

e. In a device ol the class described, a container for molten metal, separable moulds, iluid pressure actuated means to separate the moulds at selected times, a second fluid pressure actuated means cooperating with the container and the moulds to force molten metal to the moulds at selected times, aV source of fluid pressure, and control means acting between the source of iiuid pressure and the two fluid pressure actuated means to actuate the separable moulds and to torce molten metal to the moulds in al selected sequence, and means being `responsive to the variations in the level of the molten metal in the container to vary the amount of iluid pressure available to actuate the second fluid pressure actuated means to maintain the quantity of molten metal forced to the moulds substantially constant. i

5. ln a device of the class described, a container for molten metal, separable moulds, a source oi fluid pressure, fluid pressure actuated means to open and close the moulds, pump means in the molten metal to lift the molten metalv above its level in the container and to force molten metal into the molds, a second iluid pressure actuated means to actuate the pump means, control meansfor the first and second iiuid pressure actuated means to control their sequence of actuation, and an automatic control means independent of the first control means for the second duid pressure actuated means to control the amount oi molten metal forced into the moulds by the pump means.

6. in a device oi the class described, a contalner for molten metal, separable moulds, a source of fluid pressure, an elongated chamber in the container extending from above the level of the molten metal to a substantial distance titl below the surface into the molten metal, conveyor means in communication with the lower end of the elongated chamber, extending above the surface of the molten metal and in cornmunication with the moulds', a one-way valve adjacent the lower end of the elongated chamber to place the chamber in communication with the molten metal to maintain the same. level of molten metal in the chamber, means cooperating with the source of uid pressure and the upper end of the chamber to place a fluid pressure on the surface of the molten metal at selected times to force molten metal from the conveyor means into the moulds, and means responsive to changes in the level of the molten metal to vary the amount of the fluid pressure acting on the surface of the molten metal in the chamber, whereby the conveyor means will deliver a `substantially constant quantity of molten metal to the moulds.

'7. In a device of the class described, a conltainer for molten metal, separable moulds, a

source of uid pressure, fluid pressure actuated lmeans to-open and close the moulds, a closed cylinder positioned in the molten rmetal in the container, a one-way valve in the lower end of the cylinder to allow the molten metal to iow into the cylinder to fill the cylinder except for a relatively small space adjacent its upper end,

conveyor means communcatingwith the cylinder adjacent its lower end to convey molten metal in the cylinder to the moulds,I iiuid pressure means cooperating with' the source of iiuid pressure to place'al variable fluid pressure on the surface o'f the molten metal in the cylinder t0 force the moltenrmetal through the conveyor means into the moulds, control means cooperating with the source of fluid pressure, the fluid pressure actuated means and the iiuid pressure means to give a predetermined sequence of operation of the various means, means to vent the upper end of the cylinder to the atmosphere at selected times and a second control means responsive to variations in the level of the molten metal in the container to control the fluid pressure on the surface of thev molten metal in the cylinder whereby,l the conveyor' means delivers a predetermined amount of molten 'metal' to the moulds.

8. In a device of the class described, a containerfor molten metal', separable moulds, means to open and .close the moulds, iiuid pressure actuated means associated with the container to force molten metal to the moulds, a source of fluid pressure, a second fluid pressure actuated meansvcooperating with the source of pressure to create a variable uid pressure to actuate the J mined substantially unvarying amount of molten metal to the moulds.

9. In a device of the class described, a container for molten metal, separable moulds, a source of uid pressure, iluid pressure actuated means to open and close the moulds, a closed cylinder positioned in the container, a one-way valve in the lower end of the cylinder, conveyor means communicating with the cylinder to convey molten metal to the vmoulds by uid pressure acting on the surface of the molten metal, control means cooperating with the source of fluid pressure, the uid pressure actuated means and the cylinder to give a. predetermined sequence of operation, means to vent the-upper end of the cylinder to the atmosphere at selected times, and a second control means responsive to variations in lthe level of the vmolten metal in the container to control the fluid pressure on the surface of the molten metal in the cylinder `whereby the conveyor means is caused to deliver a predetermined amount of molten metall to the moulds.

10. In a device of the class described, a container for 'molten metal, separable moulds, a l

source of fluid pressure, a closed cylinder positioned in the molten metal in the container, conveyor means communicating with the cylinder adjacent its lower end to convey molten metal in the cylinder to the moulds, uid pressure means cooperating .with the source of fluid pressure to place a uid pressure on the surface of the molten metal in the cylinder to force the molten metal through the conveyor means into the moulds, control means cooperating with the source of iiuid pressure, and the iiuid pressure means to give a' predetermined sequence of operation, means to vent the cylinder to the atmosphere arid the molten metal at selected times, and a second control means responsive to variations in the level of the molten metal in the container to cause the conveyor means to deliver a predetermined amount of molten metal to the moulds.

l1. In a device of the class described, a container for molten metal, separable moulds, pump means positioned within the container and adapted to deliver molten metal to the moulds,

actuating means for the pump means, fluid pressure actuated means adapted to cooperate with the actuating means, a source of iiuid pressure, variable stop means cooperating with the actuating means, control means responsive to changes of the level of the molten metal in the container to vary the position of the stop means for the actuating means to cause the pump means to deliver a substantially uniform amount of molten metal to the moulds. v

12. In a device of the class described, a container for molten metal, a mould, means to supply molten metal from the container to the mould at selected times, and control means responsive to changes of the level o'f the molten metal in the container to control said supply means, whereby the iatter means will convey a substantially uniform amount of metal to the mould during each cycle of operation thereof.

13. In a device of the class describedfa container for molten metal, separable moulds, conveyor means operable by fluid pressure cooperating with the moulds and the container to convey molten metal from the container to the moulds at predetermined times, and controlmeans cooperating. with the conveyor means to maintain the amount of metal conveyed to the moulds substantially constant, said control means being responsive to variations of the level of the molten metal -in the container. l 14. In a device of the class described, a container for molten metal, separable moulds mounted adjacent the container, pump means mounted in the container at least partially submerged in the molten metal, conveyor means to convey the molten metal from the pumpmeans to the moulds, actuating means for the pump means, and control means for the actuating means cooperating with the level of the molten metal to vary the capacity ofthe pump means in response to variations of the level of the molten metal to maintain the amount of metal conveyed to the moulds substantially constant.

15. In a .device of the class described, a container for molten metal, separable moulds, fluid-f pressure actuated means to separate the moulds at predetermined times, conveyor means at least partially submerged in the molten metal in the container and operable by fluid pressure to convey molten metal from the container to the 16. In a device of the class described, a contaner for molten' metal, separable moulds. a source of fluid pressure, uid pressure actuated means to open and close the moulds,\ pump means in the molten metal to liftthe molten metal above its level in the container and to force molten metal into the moulds, va second v fluid pressure actuated means to actuate the pump means, control means for the rst and second iluid pressure actuated means to control their sequence of actuation, a secondcontrol means for the second fluid premura actuated means to controlv the amount of molten metal forced into the moulds by thepump means, and means to actuate the second control means responsive to changes in level of the molten metal to allow the pump means to discharge a substantially constant amount of molten metal into l the moulds.

17. In a device of the class described, a container for molten metaLvseparable moulds. uid pressure actuated means to separate the moulds at predetermined times, conveyor means at least partially submerged in the molten metal in the 35V container and operable by iluid pressure to convey molten metal from the container to thel moulds, a source of uid pressure of substantially constant pressure, control means for the uid pressure to control the sequence ofY actuation oi' the separable moulds and the conveyor means, separate power means to actuate the control means, and a second control means cooperating with the `conveyor means responsive to the level oi molten metal in the container to control the amount of uid pressure supplied thereto, to

maintain the amount of molten metal conveyed` to the moulds substantially constant.

18. In' a device of the class described, a container for molten metal, separable moulds, iluid pressure actuated means vto separate the moulds at predetermined times, conveyor means at least partially submerged in the molten metal in the container and operable by fluid pressure to convey molten metal from the container to the moulds, a source of uid pressure of substantially constant pressure, control means for the uid pressure to control the sequence of actuation of the separable moulds and the conveyor means.

separate power means to actuate the control means, and a second control means cooperating with the conveyor means and bleeding the uid pressure supplied to the conveyor means to a value which is proportionate .to the level of the molten metal in the containerv so as'to enable tl'xe conveyor means to convey a substantially constant amount of molten metal from the container to the moulds.

DANIEL DOYEN.