US3168765A - Automatic core setters for centrifugal pipe casting machines - Google Patents

Description

1965 G. o. BERNHARDT 3, 68,765

AUTOMATIC CORE SETTERS FOR CENTRIFUGAL PIPE CASTING MACHINES Filed June 8, 1962 3 sheets sheet 1 INVENTOR GERD O. BERNHARD'T 9, 1965 5. o. BERNHARDT 3, 6 ,765

AUTOMATIC CORE SETTERS FOR CENTRIFUGAL PIPE CASTING MACHINES Filed June 8, 1962 3 Sheets-Sheet 2 use.

INVENTOR GERD O. BERNHARDT Filed June 8, 1962 FIG.3

AUTOMATIC CORE SETTERS FOR CENTRIFUGAL PIPE CASTING MACHINES 3 Sheets-Sheet 3 F" T F F \O s? r l 8 v ii if if Q ii e "3 d, I H

INVENTOR GERD O. BERNHARDT A'ITORN EYS United States Patent 3,168,765 AUTOMATIC CORE SETTERS FOR CENTRIFUGAL FEE CASTING MACHINES Gerd 0. Bernhardt, Pointe Claire, Quebec, Canada,

assignor to Canada Iron Foundries Limited, Montreal, Quebec, Canada Filed June 8, 1962, Ser. No. 201,078 Claims priority, application Canada, Mar. 21, 1962,

844,807 3 Claims. (Cl. 2265) This invention relates to automatic core setters for centrifugal pipe casting machines and basically known in the trade as Delavaud machines. These generally embody cylindrical metal water-jacketed molds mounted for rotation within a carriage which i moved axially along an inclined bed or trackway during the casting operation. In this type of apparatus the carriage moves longitudinally relatively to a pouring trough through which molten metal is supplied first of all to the bell end of the pipe mold and then continuously along the length of the mold as it moves, the pipe being formed by centrifugal action achieved by the rotating mold. When the mold reaches the end of its longitudinal travel as finally to position the end of the trough at the spigot end of the pipe mold and when the complete pipe has been cast, the carriage comes to rest and the pipe is extracted therefrom at the bell end of the mold. Prior to its return to the opposite end of its runway for the next casting operation, it is necessary for an operator to insert a bell core in the bell end of the mold and to wedge and lock it in position as to provide for the initial formation of the bell end of the pipe at the commencement of the next casting operation. Similarly when the pipe is cast and the mold reaches the end of its travel as above referred to, the operator first of all removes the core holding ring prior to withdrawal of the cast pipe from the mold. Most of these two manual operations are eliminated by the pres ent invention.

While pipe casting operations on machines of this kind may be accomplished in a two-stroke cycle as above according to more recent developments in this field, the

older mode of operation required four cycles: (1) a down stroke during which the pipe is cast when the operator removes the core for the extracting operation and an expanding grabbing device is introduced to the bell end of the pipe to cause withdrawal of the pipe from the mold as the mold is caused (2) to move back up the track to its original pro-casting position and wherein the pipe leave the mold, is received on carriers and moved transversely from the carriage path, whereupon (3) the carriage is moved back down to its final casting position so that the operator may insert a new core and (4) then is moved up the track to pre-casting position for the commencement of another casting operation. In other words, after the extraction of the pipe it is necessary to move the carriage twice between casting operations, i.e. a down stroke so that the operator may place the core and an up stroke to place the mold back in the position for the casting operation. To convert such four-cycle machines to two-cycle machines, using a travelling extract-or as has been developed the last few years, requires an increase in the amount of working space with attendant high cost in terms of conversion, whereas such space may not be available. In other words, in many cases conversion may be impossible in a plant already designed I and in operation on four-cycle principle.

The present invention provides a simple means wherebyfour-cycle machines of the kind described may be converted readily to two-cycle stroke mashines by pro viding an automatic core setting means operable after the pipe has been extracted and during the return travel of the carriage towards pre-casting position as to eliminate the two intervening operation cycles, i.e. the extra stroke of the carriage back to the casting position for core setting purposes and its return to pre-casting position for the next casting operation. It also eliminates some of the manual core setting functions and which can be applied if desired with advantage to the improved type of two-cycle casting machines. Overall in particular, however it will be obvious that the invention has its major advantage in the material increased production by its capacity ofsimple conversion of four-cycle type machines to two-cycle type, thus achieving a marked advance in this particular art.

The invention will be clearly understood by reference to the following detailed specification taken in conjunction with the accompanying drawings, in which:

FIG. 1 is an enlarged perspective illustration of automatic core setting means according to the present invention mounted in conjunction with the bell end of the pipe mold carried in a centrifugal casting machine and showing the core setting device in a position to move the core into the bell end of the mold.

FIG. 2 is an enlarged fragmentary top plan view partly in longitudinal section of that end of the mold shown in FIG. 1 and illustrating the core moved into position within the bell end of the mold; and

FIGS. 3 to 6 are top plan schematic illustrations of the mold and core setter in various positions of travel of the mold carriage during the casting of a pipe.

Referring to the drawings, A indicates a carriage containing a rotary pipe casting mold, which carriage in well known manner is adapted to be reciprocated on a trackway 10 from an initial precasting position to a final casting position and wherein the pipe is cast during travel of the mold and carriage to final casting position. In FIGS. 3 to 6, the carriage is shown, respectively, in final casting position (FIG. 3) where the pipe is about to be extracted from the mold; .pre-casting position (FIG. 4); during casting (FiG. 5) where a casting is just about completed with the mold moving near to final casting position; and final casting position (FIG. 6) where extraction of the cast pipe is commencing.

Referring again to FIG. 1, the bell end of the rotary mold 11 is shown open for reception of the bell core after withdrawal of a pipe therefrom and which is approximately the position illustrated in FIG. 6. According to the invention, a movable bell core holder B is mounted on the carriage for swinging movement relatively thereto and which maybe accomplished as shown in FIG. '1 by means of the vertical hinge shaft 12 carriedin suitable brackets on the mold carriage which swingably carries a suitable lever such as the bell crank lever 13 rigidly fastened to a rim 40 of the movable bell core holder B.

15 which is designed to receive the bore of the core C in frictional fit. The core C is provided with the flanged base ring 16, the exterior face of the flange thereof being tapered as at 17 to center in the'frusto-conical opening 18 of the bell end of the mold 11. The protector sleeve 14 is secured .as shown to a driving plate 19 which backs the flanged base ring 16 of the bell core C and. is clamped towards its outer end by suitable set screws 20 passing through the rotary member or sleeve 21 of the bell core holder and which suitably carries the rotatable portion 22 anearee of the roller bearing raceway 23 which, together with the stationary portion 24, carries the roller bearings 25 therebetween, the bearing assembly being closed with suitable seals, as shown, in normal manner. The protector sleeve 14 may be enclosed by the end casing 26 which is bolted to the stationary ring element 27 to which the lever 13 is rigidly secured by means of the connector arm 13a. Alternatively end casing 26 may be omitted to permit constant inspection of the pouring operations.

Ring 27 has the annular fitting 28 rigidly fastened thereto, as by welding, and which in turn is provided with the radially extending flange 29 adapted slidably to receive the grooved adjusting ring 30 having the radially extending groove 31 and which permits of the radial adjustment of ring 30, relatively to the annular fitting 28 and ring 27 carrying it, so that the base plate 16 of the core will adjust to fit accurately within the frusto-conical opening 18 of the bell end of the mold. Since the movable and stationary parts of the core holder are carried by the radial adjustment ring 30, it is clear that required limited radial shifting of the bell core C and its flange ring 16 will be achieved as the latter is being positioned within the opening 18 of the bell end of the mold.

The driving plate 19 is formed with a series of notches 32 in its periphery which are designed to register with and straddle suitable driving pins 33 carried on the end of the rotary mold 11 so that when the swingable core holder B is swung, to position the core C within the open bell end of the mold 11, the driving plate 19 will be placed 1n operative driving engagement with the drive pins 33. Consequently, the rotatable parts of the core holder B are adapted to rotate with the mold. It will be clear, therefore, that the movable core holder B can be swung to position the bell core accurately within the open bell end of the mold as to provide for commencement of casting.

The .swingable bell core holder B is designed to be actuated by any suitable means, here shown (FIG. 1) as a pneumatic cylinder 34, which is suitably mounted on .the mold carriage A and has its piston rod 35 pivotally connected to one end of bell crank lever 13. The pneumatic cylinder 34 is adapted to have air lines (not shown) connected thereto in well known manner and controlled by suitable well known valve mechanism so that the piston may be caused to reciprocate as required.

Upon completion of a pipe casting operation, the cylinder 34' is actuated to pull the bell crank lever 13 as to swing the bell core holder B outwardly tothe position shown in FIG. 3, whereupon the pipe may be extracted from the mold and the operatorthen places a new bell coreon the holder B. The carriage A is then retracted in well known manner on the trackway 10 from the position shown in FIG. 3 to the position shown in FIG. 4 where the pouring trough 36 is disposed within the mold with its pouring spout located at the bell end of the mold.

" As it reaches this position, or just prior thereto, the cylinder 34 is actuated to push the bell crank lever 13 and locate and secure the bell core within the previously open bell end of the mold 11. Pouring may then commence in the normal manner with the carriage moving from the position in FIG. 4 towards final casting position and during which time the pipe is being cast by centrifugal action due to the rotation of the mold. On completion of casting, as in FIG. 6, the cylinder 34 is actuated to cause the bell core holder B to swing outwardly and remove the core so that the extractor may be caused to enter and remove the pipe from the mold. The pipe is conveniently removed by introducing the expanding pipe grabbing device 37 into the bell end of the pipe and as the carriage A is retracted, the'pipe is extracted, received on suitable carriers (not shown) and moved transversely out of the way, 'as generally illustrated in dotted lines in FIG. 4. Prior .to or during extraction of the pipe, the operator will remove the core and ring, if it still remains on the bell core holder B, and place a new bell core and ring on the holder. Thus, when the carriage moves back to its pre-casting position as the pipe is extracted, the automatic insertion of the bell core in the bell end of the mold after extraction of the pipe provides for commencement of the next pouring operation. Pipe casting is thus achieved in a two-cycle operation of the apparatus as compared to four-cycle operation previously necessary, in this type of installation, wherein after extraction the carriage was moved back again to the final casting position so that the operator might insert and fasten a new core within the bell end of the mold whereupon the carriage was moved back to pouring position. Thus without altering the four-cycle type installation in any way, such aninstallation is automatically converted into a two-cycle operation with obvious increase in production.

The automatic core setting thus achieved while providing the primary advantage above described also achieves additional advantages since it eliminates the necessity for the operator to set a core in the bell end of the mold and fasten and wedge it as in past practice, as well as the necessity of manually releasing said fastening means at the end of the casting operation. Consequently, on newer two-cycle installations it will prove of advantage as well but, primarily, as above indicated, it is of particular advantage in converting four-cycle installations into twocycle without the necessity of increasing the space of operation and which is a requirement of two-cycle installations where the pipe extracting operation is achieved by an extractor operating on a long trackway and which Withdraws" the pipe completely from the mold and away from the carriage prior to the return of the carriage to pre-casting position.

It is to be understood that the foregoing illustrates a preferred embodiment of my invention and which is identified in principle with a captive movable bell core holder carried on a rotary pipe mold containing carriage employing controllable means for moving said bell core to a position within the bell end of the pipe mold and withdrawing it therefrom at predetermined stages of operation of the pipe molding apparatus. Consequently, changes may be made in the mounting and construction of the movable bell core holder including as well the shiftable core centering structure without departing from the spirit of the invention.

What I claim as my invention is:

l. in a centrifugal pipe casting machine employing a rotatable mold within a travelling carriage, a movable bell core holder adapted to carry a bell core and swingably mounted on a hinge fixed to said carriage to one side thereof adjacent the end of the carriage, the axis of said hinge lying in a plane extending at right angles to the longitudinal axis of said mold, controllable means for moving said holder to position said core operatively within one end of said mold for commencement of a casting operation and for moving said holder away from said mold after completion of casting to permit axial withdrawal of the cast pipe from the. mold, said bell core holder having radially shiftable means supporting said core for centering said core accurately within the open end of the mold.

2. The combination with a reciprocal carriage containing a rotary pipe casting mold, of a bell core holder jace'nt to that end of the carriage from which the bell end of the pipe mold is accessible, the axis of said hinge lying in a plane extending at right angles to the longitudinal axis of said mould, said holder being adapted to receive and carry a bell core and being swingable towards the bell end of said mould to center said bell core and secure it within and closing said bell end of said mold for casting purposes and swingable away from said bell end of the mold to permit withdrawal of the cast pipe therefrom, and controllable means operable at a predetermined time prior to casting and after casting respectively for 6 References Cited by the Examiner UNITED STATES PATENTS 1,942,919 1/34 Enrich et a1. 2265 2,107,322 2/38 Anderson et a1. 2265 3,074,130 1/63 Wittmoser et a1. 22-65 MICHAEL V. BRINDISI, Primary Examiner. WILLIAM J. STEPHENSON, Examiner.

Claims (1)

1. IN A CENTRIFUGAL PIPE CASTING MACHINE EMPLOYING A ROTATABLE MOLD WITHIN A TRAVELLING CARRIAGE, A MOVABLE BELL CORE HOLDER ADAPTED TO CARRY A BELL CORE AND SWINGABLY MOUNTED ON A HINGE FIXED TO SAID CARRIAGE TO ONE SIDE THEREOF ADJACENT THE END OF THE CARRIAGE, THE AXIS OF SAID HINGE LYING IN A PLANE EXTENDING AT RIGHT ANGLES TO THE LONGITUDINAL AXIS OF SAID MOLD, CONTROLLABLE MEANS FOR MOVING SAID HOLDER TO POSITION SAID CORE OPERATIVELY WITHIN ONE END OF SAID MOLD FOR COMMENCEMENT OF A CASTING OPERATION AND FOR MOVING SAID HOLDER AWAY FROM SAID MOLD AFTER COMPLETION OF CASTING TO PERMIT AXIAL WITHDRAWAL OF THE CAST PIPE FROM THE MOLD, SAID BELL CORE HOLDER HAVING RADIALLY SHIFTABLE MEANS SUPPORTING SAID CORE FOR CENTERING SAID CORE ACCURATELY WITHIN THE OPEN END OF THE MOLD.

Images