US2171628A

US2171628A - Die-casting machine

Info

Publication number: US2171628A
Application number: US53311A
Authority: US
Inventors: Lannert Frank
Original assignee: Paragon Die Casting Co
Current assignee: Paragon Die Casting Co
Priority date: 1935-12-07
Filing date: 1935-12-07
Publication date: 1939-09-05
Anticipated expiration: 1956-09-05

Description

Sept. 5, 1939. F. LANNERT DIE-CASTING MACHINE Filed Dec. 7, 1935 6 Sheets-Sheet l I nilnior; Fez/21?: Jaime/-25 Sept. 5, 1939. F. LANNERT DIE-CASTING MACHINE Filed Dec. '7; 1935 6 Sheets-Sheet 2 fzvenzor Frank lamzer f BY m cum @m/fim Sept. 5,-1939. F. LANNERT 2,171,628

DIE-CASTING MACHINE Filed Dec. 7, 1935 6 Sheets-Sheet 4 172092502",- fiarz/z Za/merf Sept. 5, 1939. F. LA'NNERT 2,171,528

' DIE-CASTING MACHINE Filed Dec. 7, 1935 6 Sheets-Sheet 5 lFzveni'or; Frank Larznerf Sept. 5, 1939. F. LANNERT DIE-CASTING MACHINE Filed Dec. 7, 1935 6 Sheets-Sheet 6 3E5 mu Q Patented Sept. 5, 1939' r PATENT OFFICE 2,171,628 DIE-CASTING MACHINE Frank Lannert, Chicago, 111., assignor to Paragon Die Casting Company, Chicago, 111., a corporation of Illinois Application December '1, 1935, Serial No. 53,311

8 Claims.

. This invention relates to machines for diecasting metals under relatively high pressures. The particular object of the invention is to provide a die-casting machine which shall be capable 5 of automatically and rapidly performing a cycle of operations in proper sequence and in proper 'time relation, so that the metal shall be cast under the desired pressure and the die opened after suflicient time has elapsed to permit the 10 metal to congeal. I

In the accompanying drawings, Figure 1 is a side elevation of a die-casting machine embodying the features of my invention. I

Fig. 2 is a plan view of the machine. In Figs. 1 and 2 the die is shown closed. Fig. 3 is a fragmentai side elevation, showing the die open. I

Fig. 3"- isa section on line P-J' of Fig. 3.

Fig. 4 is a fragmental sectional view, showing the die closed. I

Fig. 51s a section on line H of Fig. 1.

Fig. 6 is a section on line -0 of Fig. 1.

Fig. 71s a section on line I''I of Fig. 4.

Fig. 815 a section on line 8-4 of. Fig. 4.

Fig. 9 is a section on line 8-9of Fig. '7.

I Fig. 10 is a diagrammatic illustration of the machine.

Figs. 11, '12 and 13 tain valves.

Fig. 14 (Sheet is a fragmental plan view of an alternative form of core-pulling and inserting mechanism.

.Fig. 15 is a section on line I5.-l5 of Fig. 14. The embodiment herein shown of theinvention comprises a supporting framework consisting of a base I, a platen 2, brackets 3 and beams 4 to which the platen 2 is rigidly secured, and two parallel inclined rails 5 supported above the base I on the brackets 3 and i. The framework of the machine further comprises four guide rods 1 rigidly secured to and extending perpendicularly from the platen 2. The outerends oi the guide ,rods 1 are supported in a frame 8 having rollers 9 which stand on the rails 5. As shown in Fig. 1, the outer ends of the guide rods 1 are screwthreaded and extend through openings in the frame 8, being secured to said frame by means of nuts III. The screw-thread connection between the guide rods 1 and the frame 8 permits the framet'o be secured at the proper distance from the platen 2 in accordance with the dimensions of the dies.

The die comprises a stationarysection I I which is detachably secured to the platen 2, and a movable section I2 which is detachably secured to a are sectional views of cercarriage I3 (Figs. 1 and 6). Said carriage is slidably mounted on the guide rods 1 and has wheels I4 that run upon the rails 5. It will, of course, be understood that the shape and dimensions of the die-sections I I and I2 will vary in accordance with the work in hand.

The die-section I I may be secured to the platen 2 in any desired manner, as 'by means of clamp members ll- (Figs. 4 and 7) and may be accurately located on the'platen by means of dowel pins I4".

The means for moving the die-section I2 into and out of contact with the die-section I I and for locking the die-sections in tight contact with each other comprises four pairs of toggle links I 5, each pair of links being pivoted at one end to the carriage I3 and at its opposite end to the frame 8. When the toggles are in alined position, as shown in Figs.'1 and 4, two of the toggles extend close to the plane of the twoupper guide rods 1 and the other two toggles extend close to the plane of the two lower guide rods 1. The upper toggles are connected at their mid-points to the mid-points of the lower toggles by means of links I6. It will be seen that'the four toggles I5 and the links I6 constitute a parallel-motion connection by means of which the carriage I2 may be moved toward and away from the platen 2. The means for flexing and straightening the toggles I5 to reciprocate the carriage I3 and to hold the diesection I2 tightly pressed against the die-section II comprises a cylinder II having trunnions I1 (Fig. 3) that are carried in bearings on brackets ll which arerigidly secured to the frame 8. The cylinder I1 is located atone side of the path of movement of the die-section I2. In said cylinder is a piston I! which is secured to a plunger 20, said plunger being attached to a crosshead 20 which is pivoted to the mid-points of two pairs of toggle links 2I. The lower ends of the pair of toggle links 2I are pivoted to the mid-points of the lower pairs-of toggle links I! (Fig. 5). The upper ends of the two pairs of toggle links 2I are pivoted to the brackets I8 at 2| which is at one side of the path of movement of the die-section I2, thus making possible the use of relatively long togglelinks 2I. The locked position of the toggles I5 and 2| is determined bycontact of the piston I! with a stop portion 2| (Figs. 3 and 4). By 5 cision in the casting of the metal, and preventing the escap of metal between the die-sections.

Means has been provided for automatically inserting cores into the impression or impressions a (Figs. 6 and 9) formed between the dies and for automatically withdrawing the cores.

casting or castings to be formed. The cores are indicated in Figs. 3 and 6 by the number 22.

They are mounted for rectilinear movement per- 1 pendicularly to the direction of movement of the die-section I2 in guides 22 fastened to said diesection, and are attached to heads 22*. Each head 22 has a guide pin 22 that fits slidably in an opening in the die-section I2. The-heads 22 have a screw-thread adjustable connection to yokes. 22. These yokes are connected by means of links 23 to levers 24. Said levers are pivoted on the pivot bolts 25 to brackets 26 rigidly secured to the carriage I 3. To prevent the brackets 26 from springing under the pressures exerted in operation, they are rlgidly connected to the diesection I2 by means of rods 26". As shown in Fig. 3, several openings are formed in each bracket 26 and lever 24 to receive the p ot bolt 25 in order that the extent of movement of the core 22 may be adjusted by placing the pivot bolt 25' in. selected openings in the lever and the bracket. The rear arm of the upper lever 24' is secured to. a yoke 21. The lever 24 maybe secured to the yoke 21 at various points in accordance with the position of the core relative to the die-sections, the bolts 23 (Fig. 6) being insertable into selected -openings 29 in the yoke 21. The arms of the yoke 21 are connected to the frame 6 by means of links 36 and brackets 30" (Fig. said brackets being attachable at various points as indicated by the series of screw holes 36 (Fig. 3). The link 36 may be connected with the yoke 21 at either of two points, as shown in Fig. 3.

The rear arm of the lower lever 24 is connected'to the frame 8 by means of a link 36. It will be seen that as the carriage I3 is moved, the cores 22 willbe moved into or out of the impressions q, depending upon the direction of movementof the carriage.

If cores are to be inserted and withdrawn at right angles from the position shown in the drawings, the brackets 26 may be secured to the vertical sides of the carriage I3, at "selected points, as indicated by the screw holes 36* (Fig. 3). In such a re-arrangement, the links 30 are attached to appropriate ,sides of the frame 3.

Figs. 14 and 1 5 illustrate an arrangement for horizontally inserting and withdrawing two cores. Two brackets I35 are adapted to be secured tox'a vertical side of the carriage I3 by means of screws I36, a plurality of holes I31 being provided in the carriage to permit of locating the brackets at desired points. To facilitate the handling of the brackets I35 when the latter are being located on and secured to the carriage, I provide supporting means comprising a bracket I 38 fixed to the carriage and rotatably supporting a screw I39 that extends freely through an aperfor rotating the screw I33 when the brackets I35 are to be adjusted.

Each bracket pivotally supports a lever I, a

In the present instance, means has been provided forthus operating two cores, but it will be understood that in' practice the number of cores will depend upon the number and character of the plurality of pivot holes being formed in the brack- I et and the lever to'aflord a range of adjustment;

One arm of each lever is connected to a core by means of a link I42. The opposite arm of the lever is connected to the frame 8 through a link I43. It will be evident that as the carriage I3 and die-section I2 move forward and back 'the cores will be inserted and withdrawn. To prevent springing of the brackets I35 as the cores are pulled, each bracket is connected tothe diesection I2 by means of a tie-rod I44.v

. The means for supplying molten metal under pressure to the die comprises a pot 3| (Fig. 4)v and a furnace 32, each of which may be of any preferred character. The pot 3| is located close to the platen 2. A pump cylinder or well 33 is stationarily supported in the pot 3|, one end of the cylinder communicating with the interior of the pot by means of an inlet port 34 and the opposite end of the cylinder communicating with a gooseneck 35 by means of a channel 36. A plunger 31 in the pump cylinder 33 is connected to a piston 38 in a cylinder 33 mounted on the frame 4. Preferably the plunger 31 is connected to the rod of the piston 33 by means of a member 33 so that the plunger may be easily detached and removed when cleaningor replacement is required. Forces tending to separate the cylinders 33 and 39 are counteracted by the tie-rods 39 (Fig. 8) and turnbuckles 33.

It will be seen that by operating the piston and cylinder 36-33, molten metal may be forced from the pump cylinder 33 and through the gooseneck to an inlet member 46 which extends between the end of the gooseneck 35 and the gate of the die-section II. I v

A spreader pin 42 secured to the die-section I2. extends into the gate H to aid in directing the stream of molten metal to the several impressions of the die. Pr

' The means for ejecting or freeing a casting from the movable die-section I2 is herein shown as consisting of a. suitable number of pins 43 fixed to a head 44. The pins 43 extends slidably through openings in the movable die-section I2, said openings extending to the impressions a of the die. The head 44 is secured to the piston rod Y 45 of a cylinder 46, said cylinder being mounted upon the carriage I3 parallel with the guide rods 1. A rod 41 is securedto the head 44 and to a crosshead 43 on the piston rod 45, the rod 41 extending through a guide opening 43 in the cardie-section II when the die is closed. In the closing movement of the die-sections, the pins 56 engage the die-section II .and thus insure that the 'ejector pins 43 shall be retracted from the im-' pressions a.

It will be apparent from the foregoing that power to move the die-section I2 into and out of I operative position and to lock it in operative-position, and to pull and insert the cores 22 is furnished by the cylinder I1; that power for forcing moltenmetal into the die is obtained from the cylinder 36, and that power to eject the castings from'the die is supplied by the cylinder 46. The

means herein shown for supplying pressure fluid to these cylinders in proper timed relation and under the control of the operator will now be de-, scribed.

A power unit 99 of well-known construction is connected to an oil reservoir 9| by means of a supply pipe 82. In the present embodiment of the invention I have shown a power unit manufactured by Vickers Incorporated, Detroit, Michigan, comprising two

positive displacement pumps

99 and 69 01' the sliding vane type, but it will be understood that my invention is not limited to the use of such a power unit. The pumps 69' and 99 are arranged to be continuously driven at the same speed by means of an electric motor M or other source of power. A valve unit 69 of known construction is connected between the

pumps

99 and 69 and a pressure supply pipe 96 and a return pipe 61. -A by-pass line 63 extends between the valve unit 69 and the tank H. In said line is a by-pass valve 94 which may be opened and closed by a handle 95.

The flow of oilto and from the die-and-coreoperating cylinder I1 is controlled by means of a valve A. The cylinder 39 that forces molten metal into the die is controlled by means of a valve 13, while the cylinder 46 that operates the ejector is controlled by means of a valve C.

Oil under pressure is supplied to the valves A, B and C by means of the branched pipe 86. Oil which is exhausted from the cylinders through said valves is returned from the valves to the reservoir 9i through the branched pipe 51.

Referring first to the connections between the die and-core-operating cylinder ii and its controlling valve A: The slidable valve member of said valve is arranged to connect the supply pipe 66 alternately to

pipes

69 and 99 leading to the opposite ends of said cylinder. Fluid exhausted from the cylinder 111 through thepipes t9 and 89 leaves the valve through the ports lil'and 10, respectively, and thence flows through a passage I! that communicates with the drain pipe 61.

The opposite ends of the pressure casting cylindex 39 are connected to the valve B by means oi pipes 13 and Fluid forced from said cylinder through said pipes leaves the valve B through

ports

15 and 16 and flows thence to a passage 1? that connects with the drain pipe 61.

An accumulator tank 19 is connected at its upper end to a source of compressed air so that the tank maybe charged with air under a pressure of say, 400 or 500 pounds per square inch.

After thus charging the tank with compressed air,

the source of supply is shut off by a valve 19 so as to confine the charge of air in the tank. 19", 19 and 18 are drain cocks connected to the tank at difierent heights. The lower end of the accumulator tank i9 is connected to the valve B through a pipe it. The slidable valve member of the valve B is arranged to connect the pipes" and 19 or the pipes it and 68, depending upon the position of said valve member. The pipe 96 is connected to the accumulator tank i8 through a pipe 99, a pressure-regulating valve 8i in the pipe 65 serving to supply oil under the desired pressure (say 1,090 pounds per square inch) to the pipe 89. M is a check valve interposed between said pipes to prevent flow of oil from the pipe 99 to the pipe 99. The slidable valve member of the valve C is arranged to connect the pipe t6 alternately with pipes 23?. and 823 leading to opposite ends of the ejector cylinder 66. Fluid exhausted iromthe cylinder 56 flows through

ports

94 and 85 to a passage 89 and thence to the drain pipe 51.

The valves A and B are arranged to be operated in succession under fluid pressure. For this purpose one end of the valve A is arranged to be supplied with pressure fluid through a tube 91 that supply pipe 66.

it extends from a valve D. The construction of this valve is best shown in Fig. 11. The other end of the valve A is arranged to be supplied with pressure fluid through a tube 99 also connected to the valve D. A drain tube 99 extends from the valve D to the reservoir BI. A tube 99 connects the valve D to the pressure supply pipe 99.

As shown in Fig. 11, the oscillatory valve meniber SI of the valve 1) has a peripheral groove 92. In the initial or idle position shown in Figs. 16 and 11, the groove 92 connects the

tubes

99 and 81 so that pressure fluid is supplied to the valve A to hold said valve in the position shown in Fig. 10. The valve member 9| also has ,a peripheral groove 93 which, in the position shown in Fig. 11, connects the opposite end of the valve A through the tube 99 to the drain tube 99. When the valve member 9| is moved clockw'se to its operated position, the groove 92 connects the tubes 91- and 99, and the groove 93 connects the supply tube 99 with the tube 88, therebycausing the valve A to operate 'to connect the supply pipe 99 with the pipe Bland to connect the pipe 69 with the out-' let port 1|. The piston I9 is thereby driven downwardly to close and lock the die.

The valve member 9| is provided with a hand lever 94 for manually operating the valve D to supply pressure fluid to the cylinder I1. Automatic means is provided for restoring the valve D to its initial position after a suitable interval, said means comprising a cylinder, 95 containing a piston 99 having attached thereto a trip projection 91 arranged to engage an arm 98 fixed to the valve member 95. One end of the cylinder 95 is connected through a tube 99 to a valve ltd connected into the pipe 13. The valve M9 is of any conventional construction adapted to open communication between the

pipes

13 and 99 when the pressure in the pipe 13 reaches a desired point,

as, for example, 1090 pounds per square inch. The opposite end of the cylinder 99 is connected through a tube IN to a valve I 92 which is similar to the valve I99, the valve I92 being connected into the pipe 14. In the tube IN is a timing valve I92 to retard the flow of the oil' to the cylinder 95, but to allow oil to exhaust freely from the upper end of said cylinder when the'trip 91 is reset. Any preferred construction of timing valve may be employed, as, for example, that shown in Fig. 13. As therein shown, the valve member I 92 restricts the flow of oil in one direction, while the ball valve I92 permits oil to flow freely in the opposite direction.

The valve B, like the valve A, is arranged to be operated by fluid pressure. The opposite ends of the body of the valve B are connected to a valve E by means of tubes I93 and I94. M is a tube connecting the valve E to the pressure 896 is a drain pipe connecting the valve E to the drain pipe 91. The valve E comprises an oscillatory-valve member i91 (Fig. i2) having a peripheral groove Hill-which, when the valve is in the position shown in Figs. and 12, connects the pressure supply pipe I95 with the tube I94; and a groove I99 which connects the pipe I93 to to the drain pipe Mt. When the valve member I91 is in the opposite position the pressure supply tube I95 is connected to the tube I99 through the groove M9, and the pipes I96 and I99 are connected through the groove I99.

The valve E is arranged to be automatically operated by two trips such, for example, as those illustrated in Fig. 10. H9 is a cylinder, one end of which is arranged to be supplied with pressure fluid through a tube iii extending from H3 is a drain tube connected to that end of the valve II3 which contains the spring I". The- .4 I the 'pipe 39. The other end of the cylinder H3 is supplied with pressure fluid through a tube II2 .which isconnected to a valve H3. The valve I I3 is connected through a tube II4 to a valve II! which is similar to the valves I 09 and I82, the valve IIS being connected into the tube 38. A shut-oi! valve H5 is connected into the tube II4. The valve II3 comprises a slidable valve member H6 which is normally held in the closed position shown in Fig. 10 by means of a spring I".

valve member H6 is arranged to be slid into position to establish communication between the tubes H4 and H2 by means of an armII! (Fig. 4) fixed to one of the toggle links IS in position to engage the stem I of the valve member II gage an arm I fixed to the valve member I01.

' A trip I26, similar to the projection I24, is arranged to engage an arm I2I fixed to the valve member I01; The trip I20 is arranged to be oberated by a fluid-pressure actuator I26 similar to the actuator IIO, I 2|, I23, both actuators being connected to the pressure supply tube III and to'the drain tube I22. Pressure fluid is arranged tobe supplied to one end of the actuator for the trip I26 through a tube I28 which is connected to the tube 99 a timing valve I28 being connected into the tube I 28.

Swivel joints are provided in the various pipes to permit of the required movement of the: cylinders I! and 46. I

The valve C is arranged to be manually operated'to cause ejection of the castings. I30 is a hand lever connected to the valve member of the valve C and normally held by 'a spring I3I in position to prevent actuation of the ejector.

The operation of the machine may be summarized as follows:

I After starting the motor M, the by-pass valve 64 is closed by shifting the handle 85 to the position shown in Fig. 10. .The power unit 80 then builds up, a pressure 01', say, 1000 pounds per square inch .on the oil in the pipe 06. Oil flows through the valves 8I and 8| and the pipe 80 to the accumulator tank I8 until the oil reaches or slightly exceeds the level of the drain cock 18", any excess being drained through said cock. The cock is then closed and the motor M stopped. Compressed air is then admitted to the tank I8 until thedesired pressure, say, 400 or 500 pounds per square inch, is reached, the valve 18 being then closed. The motor M is then restarted,

whereupon oil is forced into the tank I0 through the valves 8| and 8|! until the pressure in the tank reaches the desired working pressure as determined by the valve 8|. The dotted line a: indicates the approximate level of the oil in the tank.

With the machine in the position shown in Fig. 3, the operator turns the hand lever 94 (Fig. 10) in the clockwise direction to connect the pressure supply tube 90 with the tube 88, thereby causing the valve member of the valve A to move to the position opposite to that shown in Fig. 10, thus connecting the pressure supply pipe 66 to the pipe 58, and connecting the pipe 69 to the drain pipe 01. The piston I9 is thereby driven downwardly to close the die-sections and lock them tightly together. As the closing and locking operation is consummated; the valve H3 is operated to establish communication between the tubes H4 and H2, but prmsure is not immediately supplied through said tubes to the trip actuator I23, because the valve I I0 does not open to supply pressure fluid to the tube II4 until the pressure in the tube 68 and the upper end of the cylinder I1 has risen to the desired pressure, say,

1000 pounds per square inch. When that pres- ,sure has been attained, oil is supplied through the tubes 4 and H2 to actuate the trip I24 to operate the valvemember I0I to cormect the supply tube I05 to the tube I03, whereupon pres sure fluid is supplied to the lower end of the valve B, as represented in thediagram Fig/10,

thereby causing the valve memberof the valve B to move to the position opposite to that shown in the diagram, thus connecting the pressure supply pipe I9 to the pipe I3, at the same time blanking the pipe 86 and connecting the pipe I4 to the outlet port Hi. Pressure fluid contained in the accumulator tank I8 under the predetermined pressure, say, 1000 pounds, then flows through the pipes I9 and 13 to the upper end 01' the cylinder 39, whereupon the plunger 31 is actuated to drive molten metal from the cylinder 33 into the impressions of the die and hold the .metal under pressure while it congealing.

The valve I00 allows pressure fluid to flow from the pipe "I3to the tube 99 when the pressure in 'the pipe I3 has risen to 1000 pounds. Pressure fluid flows to the upper end of the actuator I28 for the trip I26 after a delay determined by the val've I28 and thus causes said trip to restore the valve member IN to the normal or initial posi-.

' tion shown in Figs. 10 and 12. In 'suchrestoration of the valve member I01, the arm, I25 restores the trip member I24 and the sleeve valve I2I to their initial positions, as shown' in Fig. 10. The restoration of the valve member I01 causes the pressure supply tube I05 tobe connected to the tube I04, whereby the valve member of the valve B is returned to the position shown in Fig.

' 10, and pressure is supplied through the pipes 66 and I4 to retract the plunger 31 in the pump cylinder 33, the pipe I3 being connected to the ex- .haust port I5 and the drain pipe 81. The valves I00 and I 28 insure the lapse of suflicient time between the metal-injecting and plunger-withdrawing movements so that the metal in the die shall have time to harden.

After the pressure in the pipe I4 "has reached 1000 pounds, the valve I02 allows oil to flow through the tube IM to the valve I02, and thence to the upper end of the actuating cylinder 95 for the trip 91, thus causing resetting of the valve member 9I to the position shown'in Figs. 10 and 11. Such resetting of the valve member 9I connects the supply tube 90 with thetube 81, whereby the valve member of the valve A is returned to the position shown in Fig. 10. The supply'pipe 66 is thereby'connected to the pipe 69, thus caustracted and before the unlocking and opening of the die is determined by the valves I02 and I02.

Pressure flows from the pipe 69 through the As soon as the accumulator l8 acted to drive oil under high pressure into the upper end of the cylinder 39, the continuously-operating power unit 60 began recharging the accumulator with oil, oil under high pressure being thus available for another cycle of operations by the time the operator has wiped oil the contacting faces of the die-Sections, preliminary to operating the lever 94.

It will be seen that in the machine'herein disclosed the closing and locking of the die, the

insertion of the cores, the injection of the molten metal, the withdrawal of the cores, and the unlocking' and opening of the die are efiected automatically, rapidly, in correct sequence and at proper time intervals, thus reducing the attention and exertions of the operator to, the minimum. The time intervals are variable through setting of the valves i02 H and I28. Automaticity of operation is highly desirable, as the great pressure under which the molten metal is cast creates such hazards to persons in the vicinity of the machine that proper operation is essential.

While a pair of die-sections is being installed in the machine, and the necessary adjustments made to effect proper locking of the die, the sup ply of oil to the valve H3 may be cut oif by closing the valve H5 thereby shutting off the hydraulic circuits that control all the apparatus except the cylinder i'l, and thus permitting the cylinder 8'! to be operated without danger that molten metal shall be supplied to the die.

While I have described the construction herein shown with considerable particularity, it should be understood that the invention is not limited to the details illustrated, and that various changes may be made without departing from the scope of the inventionv as defined in the appended claims.

For the sake of brevity, the hydraulic cylinders and pistons for operating the die, the moltenmetal pump and the ejector will be referred to in the claims as rams.

I claim as my invention:

i. In an automatic die-casting machine having a die adapted to be opened and-closed, and a reciprocating-piston pump for forcing molten metal into the die, a hydraulic ram connected to open and close the die, a second hydraulic ram connected to actuate the pump,- a source of hydraulic pressure connected to the rams, valve means in the connections to the die ram, valve means in the connections to the pump ram, a valve controlling the operation of the first valve means, a second valve controlling the operation of the second valve means, the first valve being arranged to be manually operated in one direction, means automatically actuated in the closing of the die for operating the second valve to operate the second valve means to actuate the pump to force metal into the die, means for thereafter automatically actuating the second lalve to operate the second valve means to re- ;tore the second ram, and means for thereafter automatically operating the first valve to operate the first valve means to cause the die ram to open the die.

2. In an automatic die-casting machine having a die adapted to be opened and closed, and means for forcing molten metal into the die, a hydraulic ram connected to open and close the die, a second hydraulic ram connected to actuate the metal forcing means, fluid-pressure means for automatically actuating the first ram to close the die, then actuating the second ram to cause the metal-forcing means to force metal into the die, then actuating the second ram to restore the metal-forcing means to idle position, and then actuating the first ram to open the die. and manually operable means to'initiate operation of said fluid-pressure means.

3. In an automatic die-casting machine having a die adapted to be opened and closed, and a reciprocating-piston pump for forcing molten metal into the die, a hydraulic ram connected to open and close the die, a second hydraulic ram connected to actuate the pump, fluid-pressure means operated by the closing of the die to actuate the second ram to actuate the pump to force metal into the die, fluid-pressure means operated by such actuation of the second ram to actuate the pump in the opposite direction, fluid-pressure means operated by the last-mentioned actuation of the pump to actuate the first ram to open the die.

i. In an automatic die-casting machine having a die adapted to be opened and closed, and a reciprocating-piston pump for forcing molten metal itno the die, a hydraulic cylinder and piston connected to open and close the die, a hydraulic cylinder and piston connected to actuate the pump, a source of hydraulic pressure, valve means controlling the supply of pressure to the die cylinder, valve means controlling the supply of pressure to the pump cylinder, a valve controlling the operation of the first valve means, a second valve controlling the operation of the second valve means, the first valve being arranged to be manually operated in one direction.

5. A die-casting machine having, in combination, a platen, a die-section detachably secured to the platen, guide members secured to the platen perpendicularly thereto, a'carriage mounted on said guide members to move toward and away from the platen,-a coacting die-section detachably secured to the carriage, a frame adjustably mounted on said guide members, means including a pair of toggle links connecting the a carriage to the frame, a second pair of toggle links connecting the midpoint of the first pair to said frame, and a hydraulic cylinder pivotally mounted on said frame and having a piston connected to the midpoint of the second pair 01' toggle links, for reciprocating the carriage and looking it in closed-die position.

' 6:3. A die-casting machine having, in combination, a platen, a die-section secured thereto, a coacting die-section, and means for moving the latter section and for locking it in contact with the other die-section, said means including a toggle connecting the second-mentioned die-section to a stationary point, a second toggle connected at one end to the mid-point of the first toggle and at its other end to a stationary point located at one side of the path of movement oi the second-mentioned die-section, and a hydraulic ram connected to the mid-point of the second toggle and located at one travel of the second-mentioned. die-section.

side of the path of 7. In an automatic die-casting machine, in combination, a die, a reciprocatory pump for forcing molten metal into the die, a hydraulic ramtor closing and opening the die, a second hydraulic ram for causing'said pump to force metal into the die and for then returning the pump to its initial position, fluid-pressure means operated by the closing of the die to actuate the [second ram to cause the pump toiorce metal into the die and then return the pump to its initial position, and fluid-pressure means operated upon the return of the pump'to its initial position to actuate the first ram to open the die. v 8 In an automatic die-casting machine, in combination; a die, a reciproca'tory pump for forcing molten metah into the die, a hydraulic fluid-pressure means.

ram for closing and opening the die, a second hydraulic ram for operating saidpump through a. cycle comprising 'torcing metal into the die and then returning to its initial position. fluid-prey sure means for actuating the first ram to'close the die, fluid-pressure means automatically operated by the closing of "the die to actuate the second ram to operate the pump through its cycle, said first-mentioned fluid-pressure means being automatically operated by the return of the pump to its initial position to actuate the first ram to open the die, and manually operable means to initiate operation of the first-mentioned mam: mmmn'r.