US2892225A

US2892225A - Process and means for casting system for operating pouring ladles

Info

Publication number: US2892225A
Application number: US478166A
Authority: US
Inventors: Buhrer Erwin; Goetz Walter
Original assignee: Individual
Current assignee: Individual
Priority date: 1954-06-23
Filing date: 1954-12-28
Publication date: 1959-06-30
Anticipated expiration: 1976-06-30

Description

June 30, 1959 E. BUHRER ETAL 2,892,225

PROCESS AND MEANS FOR CASTING SYSTEM FOR OPERATING POURING'LADLES Filed Dec. 28, 1954 e Sheets-Sheet 1 INYE N 1 OR. EEVV/A/ HUI/E5? WALTER 60572 June 30, 1959 Filed Dec. 28, 1954 E. BUHRER ET AL PROCESS AND MEANS FOR CASTING SYSTEM FOR OPERATING POURING LADLES 6' Sheets-Sheet 2 |||l|| Q D Y I (26 V INVENTOR. r] EPW/A/ BOA e52 WALTER GOETZ June 30,1959 E BUHRER Em 2,892,225

PROCESS ANb MEANS FOR CASTING SYSTEM FOR OPERATING POURING LADLES Filed Dec. 28, 1954 6 Sheets-Sheet 5 FIG. 5 3a 89 z 55; 39 La: 5 '7 82 42 it; 75 AM .79

w 39 e ZQ}. g; 88 a 20 INYEN'IOR. EEWl/V BZ/HGEE WALTER 60 72' June 30, 1959 E. BUHRER ETAL 2,892,225

PROCESS AND MEANS FOR CASTING SYSTEM I FOR OPERATING POURING LADLES Fiied Dec. 28, 1954 6 Sheets-Sheet 4 INYENT OR. EEW/N aux/e52 WALTER 60572 E. BUHRER ET AL 2,892,225 PROCESS AND MEANS FOR CASTING SYSTEM FOR OPERATING POURING LADLES 6 Sheets-Sheet 5 June 30, 1959 Filed Dec. 28, 1954 INVENT OR. EEWl/V EUH/QEE WALT [E 605 7' Z June 30, 1959 E. BUHRER ETAL 2,892,225

PROCESS AND MEANS FOR CASTING SYSTEM FOR OPERATING POURING LADLES Filed Dec. 28, 1954 6 Sheets-Sheet 6 F/G- 9 I83 19/ INVENTOR. EPW/N BUHEEE WALTER GOETZ United States Patent PROCESS AND MEANS FOR CASTING SYSTEM FOR OPERATING. POURING LADLES Erwin Biihrer and Walter Goetz, Schatthausen,

Switzerland Application December 28, 1954, Serial No. 478,166

Claims priority, application Switzerland June 23,1954 9 Claims. (Cl. 22-82) This invention relates generally to casting processes or a system facilitating the filling of molds with molten 1 mits regulating the amount of molten metal reaching the out by hand andat a minimum height above the mold metal or other material whereby such molten material is delivered to saidmolds from a ladle or like container. It is an important object ofthe presentinvention to provide means presenting highly simplified yet extremely eflicient casting systems leading to reductions in the remum cost due to substantial reductions in material waste and equally substantial increases -in the proportions of acceptable articles produced in each operation.

Whenever it becomes necessary, however, to fill a subdivided mold having several pouring basins by pouring molten metal successively into the individual sprues, there arises a well-known danger thatthe second or third of these successive pouring operations may bring about an explosive combustion of the combustible gases present in the mold after the first pouring operation. These minor explosions are usually the cause for the formation of spoiled castings.

Recent investigations have, moreover, brought out how greatly all aspects of the casting process are affected by the characteristics of the casting basin, the casting spouts or spigots, and the casting speed. In conventional casting procedures for small and medium-sized molds, the casting basin is always of relatively small dimensions. It is, therefore, very difiicult to direct the pouring or casting jet to the properspot and at the same time to pour the molten metal in such a manner that the casting basin, from which the molten metal flows continuously into the mold, is at all times filled to the brim.

In foundry technique it is known that the last. casting from a ladle is poured at substantially lower temperatures than the first casting from a full ladle. A similar drop in the temperature of the molten metal occurs where a number of casting ladles must be filled successively from one bull ladle or other type of storage tank. The pouring itself, as it is carried out today, is one of the most difiicult and hardest jobs in a foundry. .The heat the provision of a scale for "the casting ladle, which perand with a rate of flow of molten metal which may be accurately controlled; g 1 Another object of the present invention is to provide means facilitating the creation of a mechanism which does not actually tilt the ladle for pouring but which permits the swinging of the ladle about a virtual axis located adjacent the free end of its spout, so that the:disstance or height between the tip of the ladle spout'and the sprue or spruescf the mold and its pouring'basin will be kept at a minimum.

These and other objects of the invention will become further apparent from the following detailed description, reference being made to the accompanying drawings, showing preferred'embodiments of the invention.

In the drawings: l a

-Fig. 1 is aside elevational view of a pouring device, partly incr'osssection, taken along line 11 of Fig. 4;

a Fig. 2 is a sectional view taken along line 2-2 of Fig. 1;

-Fig. 3 is a front view of the device of Fig. l, as viewed in the direction of arrow A, conveyor and mold of the device of Fig. 1 being omitted;

Fig. 4 is a plan view of Fig. 1, partly in cross-section taken along line 44 in Fig. 1;

Fig. 5 is a view of the device of Fig. 4 as seen in the direction of arrow B and in conjunction with a weighing device and a collector or storage tank;

Fig. 6 is a sectional elevational view of a further em bodiment of the device of Fig. 1 taken along line 6-6 of Fig. 7;

Fig. 7 is a view of .the device of Fig. 6, viewed in the direction of arrow C;

Fig. 8 is an electrical control diagram for a filling and weighing device; and

Fig. 9 is a similar control diagram for an automatic pouring device.

Referring now more particularly to the drawings, there is disclosedin Figs. 1 to 3 a novel system for swinging and controlling a pouring ladle.

In Figs. 1 to 5 there is shown a pair of rails 21 on which a truck 23 on wheels 24 runs parallel to a mil supported conveyor 25 which carries the molds 26. On the truck 23 is supported in bearings 27 and rotatably mounted on two pivots 28 a casing 29. A motor 30 drives by means of "a reduction gear 31 a worm shaft 32 which in turn drives a worm gear 33 on a shaft 34,

gears

35 and 36 on said shaft 34 engaging with

gear racks

37 and 38, respectively (Fig'. 2).

Gear racks

37 and 38 are movable in

guides

39 and ,40 and carry at'the lower end asupportmember or frame 41 to which levers 42 and 43 are linked byfmeans'of pivots 44 and 45, lever 43 forming a crank. By'meansiof pivots '46 and 47, each of these levers is also linked to an arm member or angle piece 48,. 49 which is displaceable in parallel'relationship with respect to the frame 41, andwhich by means of

bearings

50 and 51 and

pivots

52 and 53 carry acasting ladle 54. Attached to the casting ladle 54 is areceptacle 55 which may be filled withsteel shot 56. A piston rod 57 rotatably supported by part 58, which is; firmly 'connectedwith the frame '41 carries acylinder 59- linkegl by means of pivot 6001; par-r61, which is firmly connected with elbows or

angle pieces

48 and 49.

It will be noted that frame 41 forms withlever means 42 and 43 and with respective portions of

saidangle pieces

48, 49 parallelogram'formingguide means for ladle 50; to which the remaining or extension portions of said'angle pieces are'operatively connectedat

pivot pins

52, 53, as aforesaid.

When compressed air is supplied to cylinder 59, the latteris lifted and causes thereby shifting of

levers

42 and 43, and also of

elbows

48 and 49 from a position indicated inFig. in the

directionof arrows

62 and 63 toithe position shown in Fig. 1. Upon release of compressed air'from cylinder 59, the latter drops from the position indicated in Fig. 1 to the position shown in Fig. 5; and with it all parts linked thereto by pivot pins or bolts 46 and 47. Firmly connected to lever 43 are two

levers

64 and 65, which by means of balls and

sockets

66, 67. and rods 68'and 69 are joined to the casting ladle 54 by means ofpivot

pins

70 and 71, rod .69 beingarranged for parallel displacement with' respect to arm member 49',in'accordance'with'the movement'of crank 43.

A single-acting cylinder 72 pivots on pin 73 of'truck 23 on the one hand andby'means of piston rod 74 and pin 75 on part 76 on the other hand which connects said two

guides

39 and 40. When compressed airis fed into cylinder 72, it pushes these

guides

39 and 40 into the position shown in Fig. 1. When the compressedairis discharged, a spring (not shown) returns

guides

39 and 40 .to .the position indicated in Fig. 5. Adjacent plate 77 which'isrigidly connected to bracket'78 (Figs; 3 and' 5) a lever 79is mounted on a shaft 80 which is. firmly attached to a lever 81 (Fig. 5). To lever 81 there is coupled an upright rod 82 connected to a blocking or .stop lever 83 having a pivot 84. Lever 83 engages a chain 85asshown in Fig. 1. Chain 85"is driven (in a manner not shown in details) by means of. shafts at the same speed as the conveyor 25. Mounted on shaft '80 is also a rotary slide air valve 86 (Fig; 3) through which the compressed air supply to cylinder 59 may be regulated.

A storage tank 87 (Fig. 5) in the bottom or floor of which there is a stopper opening 88 of conventionaldesign contains molten metal .89. A stopper 90 connected by a stopper rod 91 to a piston 92 is pressed by the tension of a spring 93 supported by casingv lid 94 against stopper opening 88 to close the same. In an annulus 95 and in the cylinder space 96 beneath the piston 92 there is an oil bath. If compressed air is fed into the air intake 97 it presses through oil bath and piston. 92 against the spring 93; piston 92 therefore rises to abut against sleeve 98 and thereby lifts the stopper 90 a certain distance, which clears the stopper opening 88 and permits molten metal to flow off. If the air intake 97 is set for escape, spring 93 will depress piston 92 and stopper rod 91 and thereby press the stopper 90 .back against the stopper opening 88 to close the latter.

If predetermining the exact amount of molten metal is not critical, a tiltable storage tank with a spout may be used in place of the aforesaid storage tank with stopper.

In a cylinder 99 (Fig. 5) there is a piston 100 with a piston rod 101 which carries a scale102. When compressed air is fed into the air intake 103 the piston 100 rises until the piston rod collar 104 comes to rest against the sleeve 105. If a casting ladle 54 is disposed above the scale 102then the former is lifted and the supporting pivot pins 52 and 53

leave the'bearings

50 and 51. The scale 102 now takes up the weight of 'thecasting ladle 54 and further half the weight of

rods

68 and 69, and moves in this elevated position (Fig. 5) freely.

A description of the mode of operation of the mechanismshown in Figs. 1 to 5 now'follows, reference being h'ad'to the control diagram of Fig. 8:

This operation is'based on the assumptionthat'batches of "six different moulds, which follow each other at a certain cycle, are poured successively from a ladle or like casting device and that the'batch-of six different moulds consists-of four difierent-mouldheights, whichare standardiied.

Let it-be assumed that the arrangement of the device and concomitant parts is in the position shown in Fig. 5, while the piston 100, the piston rod 101 and the scale 102 are still in lowered position.

When the foot-operated switch 106 is actuated, control current is supplied through circuit 107 to both the magnetic valve 109 and relay switch 110 if switch 108 is closed upon truck 23 reaching its position, indicated in Fig. 5. The magnetic valve 109 then opens. Through the compressed air pipe 111 compressed air is supplied to the space beneath piston 100 and, since the compressed air flows counter to the back-pressure 112, it rapidly raises the scale 102 and thereby the casting ladle 54, as previously described. With the hand valve 114 now in open position, compressed air is simultaneously fed to compressed air pipe 113, which through the by-pass pipe 115 flows into the annulus 95 and raises piston 92 against the action of spring 93, thereby opening the stopper hole 88 of tank 87 in the manner previously described.

Scale 102 takes up the weight of the casting ladle 54, as referred to, and molten metal begins to flow into the casting ladle 54. As the weight increases, the scale 102 shifts, and with it the corresponding indicator device 117 or the capacitance 118, respectively, which changes with the pointer position of the indicator device. Upon actuation of the magnetic valve 109, the cylinder 119 is supplied with compressed air or fluid through pipeline 120 and by means of ratchet lever 121 and ratchet 122 moves ratchet wheel 123 from position 124 of the sequence switch 125 to position 126, thereby switching capacitance 131 into the weighing process, while

capacitances

127, 128, 129 and 130 become inoperative.

When the supply or flow of molten metal increases the weight and thus changes the position of scale 102 and with it capacitance 118 so as to cause current to flow through coil 132, cutting off coil 133 from current, the differential relay 134 is tripped and by means of circuit breaker 135 opens circuit 107. The magnetic valve 109 is set for discharge.

Spring 93 rapidly depresses piston 92 as the back-pressure valve 116 opens .up, and thereby closes the stopper opening 88 as previously described. Simultaneously, piston 100 is lowered, but more slowly since the backpressure valve closes up and the compressed air beneath piston 100 can escape through the by-pass pipe 136 but slowly. The compressed air escapes from cylinder 119 and ratchet lever 121 is retracted by means of a spring (not shown), so that the ratchet wheel 123 is locked in its position by ratchet or pawl 137, which pivots on a rigid bearing block 138. Since

capacitances

127, 128, 129, 130 as well as capacitance 131 are all adjustable according to the amount of molten metal required for the respective mold, the performance of operation described above, causes that an amount of molten metal necessary for the mold in accordance with capacitance 131 is automatically poured into the casting ladle.

The truck. 23 and all parts connected with it, including the casting ladle 54, are now moved over to the mold to be poured, to which capacitance 131 is coordinated.

When the limit switch 143 slides off the circuit breaker rail 144, which occurs when the casting ladle '54 is removed from the scale 102, circuit 145 is closed and placed under current. Inasmuch as the sequence switch 146 was shifted by means of ratchet wheel 123, from position 147 to position 148 in a manner previously described, current is also supplid to switch 154. Switches 149, 150,151, 152, 153, as well as switch 154, can be adjusted to the 'levelof the molds associated with them. When circuit 145is closed by means of limit switch 143, current is therefore supplied through 148, 154 and 157 also to magnet coil 160, activating switch 161 and starting'the stop motor 30 for the downstroke of gear racks 37 and 38. When earn 162 reaches switch 157, the circuit will'be broken at the proper level of frame 41 and thereby-of casting ladle 54. Stop motor 30 is shut 011 and locked. Ina similar manner, with sequence switch 146 in proper position 163, it is possible to preselect switch-155 by means of switch 153, for example; via position 164 and switch 152, switch 158 may be preselected; via position 165 and switch 151 switch 155 may be preselected; via position 166 and switch 150 switch 157 and further by means of position 147 and switch 149, switch 156 maybe preselected.

Once this casting position. (Figs. 1 and 4) has been reached, lever79 in Fig. 5 is shifted in the direction of arrow 139. Upon opening of the three-link chain 85, which is attained by skipping the center link according to the gap or spacing of the molds on conveyor 25, the blocking lever 83 is able to-enter the respective chain gap.

The truck 23 therefore moves automatically, in the casting position appropriate for mold 26, parallel to the conveyor 25 and at the speed of said conveyor. While lever 79 is turned in the direction of arrow 139, compressed air is fed to cylinder 72 by activation of the rotary slide air valve 86. The

guides

39 and 40, and therefore all parts pivoting on pin 28, are shifted from the position indicated in Fig. 5 to that shown in Fig. 1. By moving lever 79'farther in the direction of arrow 138, cylinder 59 is also supplied with compressed air by means of the rotary slide air valve 86. The two

levers

42 and 43 shiftinthe direction of arrows 62 and 63 (Fig. 1) from the position shown in Fig. 5 to the position indicated in Fig. 1, thereby moving the

pins

52 and 53 of the casting ladle 54 in the direction of arrow 140 (Fig.1) from the position of Fig. 5 to the position of Fig. 1, as previously described. The ball gudgeons or pivots 66 and 67 simultaneously move in the direction 'of arrow 141 (Fig. 1), the

pins

70 and 71 consequently in the direction of arrow 142 (Fig. 1), thus swinging the casting ladle from the position shownin Fig. l in dotted lines to the position shown in Fig. 1 in full lines.

The swinging or tilting motion of the casting ladle is composed of a movement of an axis of rotation along a circular path around the horizontal axis, and of a simultaneous rotary movement at the same angular velocity around the axis of rotation, so that the swinging motion of the castingladleis performed about an axis of rotationiideally located close to the spout of the casting ladle.

It will be understood that the circular path with respect to its radius is defined by the length of

levers

42 and 43, while the magnitude of the angular movement of the ladle corresponds to the magnitude of the parallel displacement of arm member 48. The magnitude of the rotary movement of the ladle in angular respect is equal to the magnitude of angular movement along the circular path. The horizontal or virtual axis forms the center of this circular path.

The rotations in the direction of arrows 140 and 142 occur to ensure that the casting ladle is completely emptied of its contents; The range of rotation is regulated in cylinder 59. When this position is reached, lever 42 actuates switch 167, which closes the circuit by means -of magnet coil 168, switch 159, as'the cam 162 is in switch position 157, and thereby also locking contact 169 and switch 170, which closes the stop motor circuit for the downstroke. At the same time, switch 174 is opened by means of trigger-action relay 171, since current flows through coil 172 and coil 173 is without current. Once cam 162 has reached the position indicated in Fig. 8, the

stop motor 30 is shut off and locked, while the pouring or ladle device has resumed its elevated position shown in Fig. 5. At the same time, lever 79 is returned, counter to the direction of arrow 139, to starting position shown in Fig. 5. Thus the rotary slide air valve 86 opens the feed pipe of

cylinders

59 and 72, the casting ladle 54 rotates counter to arrow directions 140 and 142 from the position shown in Fig. 1 in full lines to the position shown in Fig. 1 in dotted lines, and the guides .6 39 and 40 are swung back around pivots 28 from the position shown in Fig. 1 to the position shown in Fig. 5.

Inasmuch as the return of lever 79 causes the release of blocking lever 83 from chain 85, the truck 23 may now be manually returned to the position indicated in Fig. 5. The casting ladle 54 is beneath the stopper opening 88, so that the operation may be repeated.

The same performance of operation lends itself to trouble-free, successive pouring of any number of molds of varying height and requiring difiering amounts of molten metal by employing appropriate arrangements as described. Likewise, it is easily possible to operate simultaneously two casting devices which alternate, so that, while one casting device pours the molten metal already received into the mold, the other is being supplied with the necessary amount of molten metal from the storage tank 87 and vice versa, while one casting device picks up the amount of molten metal required at the storage tank 87, the other one is pouring the required quantity of molten metal into the corresponding mold. Moreover, if the track on which the truck 23 runs is an endless one, it is readily possible to operate any number of casting devices simultaneously with one conveyor.

Of course, the invention is not limited to utilization of adjustable capacitances for the weighing operation. It is also possible to work by means of contacts or with compressed air regulating systems equipped with jets, or with other conventional systems. If only one casting device is used, variations in the dead weight of the casting ladle during operation may be compensated for by corresponding adjustment of such dead weight at the scale.

While control wiring diagram of Fig. 8 is based on the premise that an operator is assigned to each casting device, Fig. 9 shows a control wiring diagram for fully automatic operation.

Since the switching operations of this control wiring diagram are largely identical with those of control diagram Fig. 8, operation of the control wiring diagram of Fig. 9 is described only in as far as it dilfers from that of Fig. 8. A control drum 175 which is driven by the motor which drives the conveyor 25 and which makes one revolution while the conveyor advances from one mold part to the next, controls a switch 176 by means of a cam 177, which performs the same function as the foot-operated switch 106 in Fig. 8. In this way, the whole previously described sequence of operational steps for pouring ofi a fixed quantity of molten metal into the casting ladle 54 is initiated and executed in the manner referred to above. By means of control cam 178 switch 179 is now operated. This switch, by means of magnet coil 180, cuts into the circuit locking contact 181 and switch 182, whereby electric current is supplied to the stop motor 183 and magnet coil 191 (which are not shown in Figs. 1, 3 and 5), thus starting the motor of the truck 23.

When limit switch 143 disengages circuit-breaker rail 144, then, as previously described, adjusted height position will be caused by means of motor drive 30. When the truck 23 approaches the pouring or casting position (Fig. 4), cam 184 lifts change-over switch 185, whereby current is established to flow through magnet coil 186 which will attract locking lever 83. Since the locking lever 83 rests on the chain 85, it cannot perform any further rotational movement about pivot 187.

However, once the truck 23, moving in the direction of arrow 188, reaches the position of chain opening 189, then the locking lever 83 is able to enter the chain opening 189 thereby opening switch 190, which by way of magnet coil opens switch 181, thus shutting 011 the stop motor 183 and disconnecting magnet coil 191, which is located between motor and undercarriage. By means of locking lever 83 (Fig. 5), the truck 23 in the position shown in Fig. 4, is now led through chain 85 along the conveyor 25. In the meantime, earn 192 activates a rotary sliding air valve 193, feeding compressed air to cylinder 72, thus causing in the manner already described the rotary movement about pivots 28. Another cam 194 now activates a rotary slide valve 1.95, through which compressed air is also supplied to cylinder 59, thus initiating the tilting motion for emptying of the casting ladle 54.

Once mold 26 has been poured, the stop motor 36 is again automatically started by way of switch 167, and the elevation adjustment is returned from the position shown in Fig. l to the position shown in Fig. 5, as above referred to. A cam (not shown) sets rotary slide valve 195 for exhaust or discharge, thereby returning the casting ladle 54 from the position shown in Fig. l to the position which in Fig. 1 is shown in dotted lines. Another cam (not shown) sets rotary slide valve 193 too for exhaust or discharge, thereby returning by way of cylinder 72, the

guides

39 and 40 from the position shown in Fig. l to the position shown in Fig. 5.

Since cam 184 releases change-over switch 185, current is supplied by way of switch 196, which is opened by circuit breaker rail 197 in the position of Fig. only, to magnet coil 198, which actuates by way of switch 199 the travel stop motor 183 and electrical clutch 191, for causing return of the truck 23 from the position of Fig. 4 to the position of Fig. 5. Simultaneously, coil 186 is without current, thus releasing locking lever 83, whereby truck 23 is disengaged from chain 85. When the position of Fig. 5 is reached, the travel stop motor 183 is switched ofi by circuit-breaker rail 197, while electric clutch 191 continues to operate. Cam 177 now actuates switch 176 once again, thus repeating the aforesaid operation. 4

In Figs. 6 and 7, a conveyor 25 is shown with a mold 26 ready for pouring. Suspended from two parts 290 and 201, which are connected with a truck (not shown) similar to truck 23 running on rails (not shown) and parallel to conveyor 25, is a cylinder 202. This cylinder has a lid 203, with a permanently built-in piston rod 284 connected to a piston 205. When air supply line 286 by means of a rotary slide valve (not shown) is set for exhaust, the spring 287, which rests upon cylinder bottom 28%, presses under its tension against cylinder head 209 of cylinder 21G, thereby raising it and all parts mounted on cylinder 210 until collar 211 of cylinder 210 is arrested by cover 208.

When by way of a rotary slide valve (not shown) compressed air is fed into compressed-air pipe-line 206 and thereby to cylinder 210, cylinder 210 and all parts mounted thereon are lowered. Mounted on cylinder 21% is a part 212, which has bearings for

pivots

213 and 214.

Pivots

213 and 214 are fitted to a part 215, through which a bore extends to accommodate double lever 216 provided with collars 217 and 218, to prevent lateral axial shifting. Mounted at one end of the double lever 216 is a casting ladle 219, and at the other end adjustable by threaded nut 220 a sliding counterweight 221 and further a handle 222.

In operation, counterweight 221 is so positioned that it balances the dead weight of the casting ladle 219. The device of Figs. 6 and 7, used primarily for small amounts of molten metal and in non-automatic operation, operates in the following manner:

Let us assume that the casting ladle 219 is empty and rests upon a scale in a manner similar to that shown in Fig. 5. Thus, cylinder 210 and all parts mounted thereon are in their uppermost position, since the air supply line 2% is connected to the exhaust by way of the rotary slide valve (not shown). The scale, in contrast with Fig. 5, rests upon a solid base. Discharge of the necessary quantity of molten metal from the storage tank located above it, occurs essentially as illustrated in Figs. 5, 8 and 9 and is therefore not further described.

Once the necessary amount of molten metal has been supplied, the device is moved over to the mold to be poured, by means of a truck (not shown) with the handles 222' so as to keep the double lever 216 in balance. y way of a double push-button switch 223, which by a sus'- pension cable 224, is connected toa magnet valve (not shown), compressed air is fed into. the compressed-air pipe-line 286, until cylinder 210, and with it the casting ladle 219, have been sufficiently lowered so that the mold can be poured. While the mold is being poured in regular manner (Fig. 7), the load carried by cylinder 211 is reduced. This reduction results in added compression of the air contained in the compression chamber of cylinder 210, which begins to rise. By'providing a suitable spring 207 of adequate tension and a piston 205 of a suitable cross-sectional area, this rising of cylinder 210 may be made to offset approximately the lowering of pouring lip 225 of the casting ladle 219, when the casting takes place. This makes it possible for double lever 216 to remain in nearly horizontal position during the aforesaid casting operation.

These operational steps for casting and pouring the molds with at least two sprues offer the following advan tages over heretofore known procedures.

A number of small sub-molds (pattern plates) with their individual sprues may be combined into a'larger mold and jointly molded and poured by means of a casting basin of adequate size that can every time be suitably placed centrally near the longitudinal edge of the mold. This offers the advantage that the pouring from the casting ladle can be done at a level ensuring minimum of height for pouring. In addition, the invention permits tilting of the casting ladle on an imaginary axis of rotation located close to the lip of the ladle. Both developments make it possible to cast with a low pouring jet.

Pouring exactly as much metal from the casting ladle as flows off through the sprue openings of the mold so as to keep the casting basin constantly filled, and to stop pouring at the precise moment when filling has been completed so as not to spill extraneous metal unncessan'ly, are requirements which were nearly impossible to fulfill under the heretofore known casting methods, but which are met in every respect and readily maintained in the present casting system herein described.

The radically simplified casting operation requires from the operator, if one is still needed, considerably less strain than any heretofore known system. Pouring holds less danger of accident, too, as the molten metal splashes less and as an overflow at the end of the filling operation is made impossible.

If a mold to be poured consists of several sub-molds with corresponding sprue openings, the flow of molten metal enters the individual subrmolds almost simultaneously. Injuries of the mold through explosions due to the formation of gases, and their ill effects on the casting, are therefore eliminated.

As the system according to the invention lends itself to the simultaneous pouring of smaller castings as well as of large molds of the most widely difierent types and with the most widely different filling requirements, and since the casting operation consists largely of a rapid pouring of the molten metal from the casting ladle into the mold (regardless of the requiredpouring speed, which is determined by the cross-sectional area of the mold sprue openings), the pouring efficiency per pouring device is multiplied, and the crew required for the pouring of molds is reduced or,.in,-the case ofautomatic pouring, completely eliminated.

Since each casting ladle iszemptied completely with every casting, the differences in the temperatures of the molten metal arising from the pouring of several 'molds from one and the same casting ladle are avoided.

Since with a reduced number of casting ladles increased quantities of molten metal are poured, the average drop in the temperature :between the time when the molten metal leaves the melting aggregate and the time when it enters the mold is substantially reduced, so that the casting metal does not have to be overheated as heretofore required.

Thus, the over-all result of the invention described herein resides in a better quality of castings, substantially improved production and, in the case of fully automatic operation, complete elimination of a crew, or, in the case of semi-automatic operation, a pouring efficiency increased several times, as well as an increase of production efficiency.

Various changes and modifications may be made without departing from the spirit and scope of the present invention and it is intended that such obvious changes and modifications be embraced by the annexed claims.

Having thus described the invention, What is claimed as new and desired to be secured by Letters Patent is:

l. A system for swinging a member about one axis, which is independent of said member, comprising first means including movable parallelogram means supporting said member and adapted to guide said member on a circular path about said one axis for carrying out a first angular movement of said member with respect to said one axis, second means including displaceable rod means connected to said member and adapted to rotate said member about another axis movable on said circular path for carrying out a second angular movement of said member about said other axis, and third means including crank means interconnecting said parallelogram means with said rod means for correlating said guide movement of said parallelogram means and said displacement of said rod means in a manner so as to simultaneously impart equal first and second angular movements to said member about said one axis and about said other axis, respectively, to thereby swing said member about said one axis as a result of said first and second correlated angular movements.

2. A system for swinging a pouring ladle about one axis located adjacent a spout of said ladle, comprising first means including movable parallelogram means supporting said ladle and adapted to guide said ladle on a circular path about said one axis for carrying out a first angular movement of said ladle with respect to said one axis, second means including displaceable rod means connected to said ladle and adapted to rotate said ladle about another axis movable on said circular path for carrying out a second angular movement of said ladle about said other axis, and third means including crank means interconnecting said parallelogram means with said rod means for correlating said guide movement of said parallelogram means and said displacement of said rod means in a manner so as to simultaneously impart equal first and second angular movements to said ladle about said one axis and about said other axis, respectively, to thereby swing said ladle about said one axis as a result of said first and second correlated angular movements.

3. The combination, in a metal pouring system, of a ladle having a pouring spout for discharging molten metal to be poured, with parallelogram means including support means, crank means, lever means, and arm means, said lever means and said crank means hingedly interconnecting said support means with said arm means at spaced locations of said support means and said arm means, respectively, for parallel displacement of said arm means with respect to said support means, pivot means at said arm means rotatably supporting said ladle, and rod means hingedly interconnecting said crank means with said ladle at a point remote from said pivot means, said rod means being connected to said crank means and said ladle means for parallel displacement with respect to said arm means, whereby upon parallel displacement of a predetermined magnitude of said arm means with respect to said support means, said ladle is moved along a circular path whereby said rod means is displaced by said crank to rotate said ladle about said pivot means, the angular magnitudes of said circular path movement and of said rotary movement, respectively, of said ladle corresponding to said predetermined magnitude of said parallel displacement of said arm means and being equal with respect to each other, to thereby effect a predetermined swinging movement of said ladle about an axis forming the center of said circular path.

4. The combination according to claim 3, further comprising drive means interconnecting said support means with said arm means and operable to effect said swinging movement of said ladle.

5. The combination according to claim 3, further comprising guide rail means, and carriage means movable along said guide rail means, said guide means being connected to said support means.

6. The combination according to claim 5, said carriage means forming a trolley, said support means being suspended from said trolley.

7. The combination according to claim 6, further comprising lifting means interconnecting said support means with said trolley and adapted to raise and lower said support means.

8. The combination according to claim 7, said support means being suspended by said trolley for horizontal movement transversely with respect to said guide rail means and for vertical movement.

9. The combination, in a metal pouring system, of a ladle means provided with a pouring spout end for dis charging therefrom a quantity of metal, with parallelogram forming guide means for tilting said ladle means, said guide means including a frame provided with first pivot means, respective first lever means linked to said frame at said first pivot means, second pivot means, a pair of angle pieces, said ladle means being provided with third pivot means facilitating support of said ladle means, said angle pieces being connected through said second pivot means to said first lever means and through said third pivot means to said ladle means, whereby said first lever means extend in parallel relation to each other for circular movement about said first pivot means, fourth pivot means, second lever means fixedly connected to predetermined ones of said first lever means and carrying said fourth pivot means, fifth pivot means located at said ladle means at a location below said third pivot means, rod means interconnecting said fourth pivot means with said fifth pivot means, and means for regulating the range of rotation of said first and second lever means and of said angle pieces.

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