US2486388A

US2486388A - Ball casting machine

Info

Publication number: US2486388A
Application number: US555442A
Authority: US
Inventors: Willard C Brinton
Original assignee: Individual
Current assignee: Individual
Priority date: 1944-09-23
Filing date: 1944-09-23
Publication date: 1949-11-01
Anticipated expiration: 1966-11-01

Description

Nov l, 1949. w..c. BRINToN BALL CASTING MACHINE 4 Sheets-Sheet l Fil'ed Sept. 23, 1944;

- INVENTOR. W/LLARD C BR//vro/v NOV l, 1949. w, c, BRlNTQN I 2,486,388 I BALL CASTING MACHINE Filed sept. 23,`1944 4 Sheets-Sheet 2 l INVENTOR.

VV/LA RD C. 'R//vro/v I Afforneg NOV l 1949- w. c. BRINTON am. CASTING MACHINE 4 Shee'ts-Sheetl 3 Filed Sept. 23. 1944 FIG. i5

Fl'G. I5

FIG. i7 kN@ FIG. ZI

4 Sheets-Sheet 4 Filed Sept. 23, 1944 M40/n. hat

lliAllllllll Illllllh" mms/TOR. W/L ARD C BRM/TON gab A Hor/1e y Patented Nov. 1, 1949 UNITED STATES PATENT OFFICE 7 Claims.

This invention relates to improvements in automatic machines for casting grinding balls and similar articles.

Wherever rocks and ores are to be reduced to a powder for any reason, or purpose, as for preparing metaliferous ores for treatment for flotation, they are, as a rule, crushed and then ground in a ball or rod mill. In the grinding operation the balls employed are subject to the abrasive action of the materials ground which soon reduces the size of the balls to such an extent that they must be replaced. Balls for grinding mil-ls are either forged from steel or least from iron, and must have the required grain structure and hardness for long life.

Balls from cast iron are usually cast in water cooled molds and thus acquire a chilled outer surface that is hard and a grain structure which is tough, which characteristics make them last a long time compared with balls cast in sand molds.

Various kinds of machines have been invented and usedfor casting grinding balls, some of which are to a certain degree, automatic.

It is the object of this invention to produce a grinding ball casting machine which shall be of a sim-ple and substantial construction and which can be manufactured and sold for less than similar machines of different construction.

Another object is to produce a machine of the type specified which can be made almost entirely from commercial forms of structural steel thereby eliminating to a great extent the cost incident to the preparation of expensive patterns and .special tools.

A further object of this invention is to produce a ball casting machine having two spaced and inclined channels for the reception of substantially cubical mold blocks and to provide the same with means for moving the blocks upwardly in one channel and downwardly in the other channel and to provide means for shifting the blocks from one channel to the other.

Another object is to produce a machine o' the type specied in which the mold blocks move upwardly in straight rows during the casting operation in response to a force applied to the lo-wermost block, as distinguished from circular paths, whereby the blocks may be readily cooled.

Another object is to produce a casting machine in which the mold blocks may be rocked relative to each other while the metal is still molten and while it is setting so as `to facilitate the removal of the balls. y

A further object is Yto produce a machine in which the mold blocks are caused to move over a convex supporting surface to break the groove metal or sprue.

Another object is to :produce a ball casting ma-` chine in which the mold blocks are arranged in substantially straight and horizontally inclined rows and the metal allowed to flow downwardly through surface grooves that are in communica- -tion with the mold gate and in which lmeans is provided for partially cutting and for chilling the metal in the block grooves to facilitate breakage.

A further object is to produce a machine in which the expansion of the mold blocks is utilized for bre-aking the .groove metal that joins the sprues.

Another Objectis to produce a machine having separate mold blocks in which the force exerted on them during the shifting of the blocks tends to urge their contacting lsurf-aces into .engagement with each other and in which the expansion, due to the heat, also serves to urge the adjacent block surfaces into closer contact.

A further object is to produce a machine in which the degree of cooling can be regulated by changing the position of the pouring means.

The above and any other objects that may become apparent as the description proceeds are attained by means .of a construction and an arrangement of parts that will now be described in detail and Vfor this purpose reference will be had to the accompanying .drawings in which the invention has beenillustrated, and in which:

Figure 1 is a top plan view of the casting ma.- chine, shown in a more or less diagrammatic manner, with portions thereof `omitted and other portions broken away;

Figure 2 is a side elevation of the machine shown in Figure 1;

Figure 3 is. a transverse section taken on lines 3-3, Figures 1 and 2;

,Figure 4 is a top plan view yof a mold block;

Figure 5 is an end elevation of the block shown in Figure 4;

Figure 6 is a side elevation of the 'block shown in Figure 4 Figure 7 is a transverse Isection taken on line 1 1, Figure 4; y

Figure 8 is a transverse section simi-lar to that shown in Figure 7, but showing a modified construction in which the center part of the block is made from highly heat conductive material, vsuch as copper;

Figure 9' is a top plan view .of a mold block whose .outer surface .is provided with a replaceable layer of .poor ,heat .conducting material;

Figure is an end View of the block shown in Figure 9;

Figure 11 is a fragmentary top plan view showing the relationship of the several parts and the position of the groove metal notching wheel;

Figure 12 is a side elevation of the part shown in Figure 11;

Figure 13 is a section through a sprue showing the hollow material, the same as it appears immediately before the opening is closed by the flowing metal;

Figure 14 is a transverse section taken on line III-I4, Figure 13;

Figure 15 is a fragmentary top view showing means for rocking the blocks as they are moved upwardly in one of the channels;

Figure 16 is a side elevation of the rocking means shown in Figure 15;

Figure 17 is a top plan view of a mold block showing each side provided with short transverse ribs for cooperation with the rocking means;

Figure 18 is an end elevation of the block shown in Figure 17;

Figure 19 is a side elevation of the block shown in Figure 18;

Figure 20 is a section taken on line 22-22. Figure 1 and shows a means for bending the row of blocks so as to effect a breaking of the groove metal;

Figure 21 shows the mold blocks arranged in one position with the groove on the lower side of the center line;

Figure 22 is a view similar to that shown in Figure 23, but shows the groove on the upper side of the center line;

Figure 23 is a diagram showing the relative positions and the relation of the several elements of the machine.

Referring now to the drawings and more particularly to Figures 1 and 2, reference numeral 5 designates the floor or some other supporting surface cn which the machine rests. One end of the machine is supported between a pair of vertical pipes 6, whose enlarged bases 'I rest on the floor. Sleeves 8 are slidably connected with pipes 6 and are held in vertical position by means of pins passing through the openings 9. A pipe III, which has been indicated by dotted lines in Figure 2, connects the sleeves 8. The upper end of the frame, which will now be described, rests on this transverse supporting member.

The casting machine comprises a frame having three parallel guide members which have been designated by reference numerals II, I2 and I3. These members are constructed so as to be of rectangular cross section and hollow, as shown in Figure 3. In the actual construction they are each formed from two six-inch channels having twoinch anges, the flanges being welded so as to form a watertight joint, the ends of these guide members are also closed with a watertight closure which does not show in the drawings. The several guides are spaced as shown in Figure 3 so as to form channels A and B. The bottoms of the channels are formed by hollow members I4 and I5, which are of the same size and constructed in the same manner as guides Il, I2 and I3. The bottom members I4 and I5 are electrowelded to transversely extending pipes IB, which hold them in spaced position. It will be seen from Figure 3, that bottom members I4 and I5 are spaced apart at the center so as to form a channel C in which is located a pipe I1, to which reference will hereinafter be made in greater particularity. Secured to the sides of the hollow bottom members I4 and I5, are outwardly extending brackets I8, which may be electrowelded thereto. These brackets have elongated openings I9. Brackets 20 are electrowelded to the bottoms of the guides I2 and I3 and bolts 2| extend through the brackets I8 and 2l] and secure the guide members to the hollow bottom members in a predetermined relation. The parts are adjusted in such a way that channels A, B and C are of uniform width throughout their length. Electrowelded or otherwise secured to the frame near the lower end thereof, as viewed in Figure 11, is a large transversely extending pipe 22, or other equivalent member, that supports the lower end of the frame from the surface of the floor and permits a rocking movement thereof so as to allow the inclination to be adjusted by means of the support shown at the lefthand end of Figure 2. Pipe II is continuous, as shown in Figures 1 and 2, and at its lower end it is provided with a cross head 23. Secured to the upper end of pipe I'I is a cross head 25 which has an upwardly extending portion 26 from which a pusher bar 21 extends rearwardly. A pusher bar 28, similar to that designated by reference numeral 27, is secured to one end of cross head 23. It will now be evident that whenever the pipe is reciprocated, the two pusher bars 2T and 28 will move in the same direction and to the same extent.

It will be observed that the guide I3 extends downwardly to a greater distance than guides II and I 2 and that guide I2 extends upwardly beyond guides II and I3, all for a purpose which will hereinafter appear.

Reference will now be had to Figure 22 from which it will be seen that the cross head 23 is secured to the end of a piston rod 3U that extends into a cylinder 3l. A piston 32 is secured to the inner end of the piston rod and is urged against the end 33 of the cylinder by means of a powerful spring 34. A three-way valve 35 is connected with the cylinder and is in communication with the inner end thereof through a passage 36. The outlet port of this valve has been designated by reference numeral 3l and the inlet port, which is connected with a source of air under pressure (not shown) has been designated by reference numeral 38. The rotatable valve plug 39 has a handle 40 provided at its upper end with a heavy weight 4I. When the handle 40 is rocked from the full, to the dotted line position shown in Figure 23, it closes the inlet port 38 and opens communication between the passage 36 and the outlet port 31, whereby the spring 34 will function to return the parts to the full line position shown in Figure 23. A valve control bar 42 has one end secured to the cross head 23 and extends across the valve handle 4D. This bar has an elongated notch 43 in which pin 44, which is connected with the handle 40, moves. In the position shown in Figure 23, the valve has just been moved to such a position that the interior is connected with the compressed air and the piston will therefore begin to move towardsthe left and when the pin 44 contacts the wall at the righthand end of notch 43, it will move the valve handle over dead center so as to permit the weight to throw it into the dotted line position whereupon the Valve will be in a position to communicate the interior of the cylinder with the outlet port.

It will be observed that this mechanism s in eifect a, motor in which movement is effected in one direction by means of air pressure and the other by means of spring 34 and that it will con- S tinue to operate in this manner as long as it is supplied with compressed air.

Although it has not been shown in the drawing, the air is admitted to the valve rthrough a very small opening so as to limit the rate at which the cylinder moves.

Attention is called at this point to the fact that the guides Il, I2 and I3, as well as the hollow bottom members I4 and I5 are water cooled, the water entering through the pipes designated by reference numerals45 and leaves through the pipes designated by reference numeral 46. The circulation of water is effected by any suitable means, which has not been shown.

Positioned in the channels A and B and resting on the bottom members I4 and I5 are mold blocks 41 of a construction which will now be described.

Referring now more particularly to Figures 4 to 10, it will be seen that the blocks 41 are of almost cubical shape, the top View as shown in Figure 4 being a square and in actual construction for use in molding a three-inch ball, the

blocks are five inches square and six inches deepv and are formed from lcast iron, except as will hereinafter be explained. The upper surface of each block has a groove 48 whose bottom is inclined slightly towards the center in the manner shown in Figure 5. The opposite ends are provided with semispherical depressions 49 and with gate openings 50 that extend to the top of the block and intersect the groove 4B. When the blocks are placed in end to end relation as shown in Figures 1, 2, 21 and 22. the semispherical depressions supplement each other to form spherical molds for the reception of the molten metal. It is some times desirable to effect a, more rapid dissipation of the heat from the molten metal, than would be effected in a solid cast iron mold block and when this is the case, the blocks are molded with a cavity 5I that extends upwardly from the bottom in the manner shown in Figure 8 and this cavity is lled with copper or any other suitable metal 52 of high heat conductivity that has a suiciently high melting point to make it suitable for thisv purpose. It will be seen that when the blocks are in position as shown in Figures 1 and 2, their lower surfaces rest on members I4 and I5 and their sides are adjacent the guides II, I2 and I3 and since all of these supporting and guide members are water cooled, the heat from the molten metal is rapidly dissipated.

In Figures 9 and 10, a slightly modified form of block has been shown. In this modification the upper surface has a depressed area whose bottom has been designated by reference numeral 53. Positioned in this depressed area is a block 54 of refractory poor heat conducting material, such as reclay. This block has a groove 48a that communicates with the gate 50a. The poor heat insulating material 54 retards the cooling of the molten metal. In order to position the block 54 the side walls of the depressed area are provided with inwardly extending projections 55. that t into suitable depressions in the sides of the bloc-k. Any other suitable means for positioning these blocks may be substituted.

With the insert 54 of poor heat conducting material, the metal will not as readily solidify in the grooves as when it is poured directly onto a cast iron surface. Instead of a thick block like shown, the grooves 48 in the cast iron blocks may be painted or otherwise covered with a thin layer of reclay, or other suitable material 'so as to form a heat insulating layer. i

The blocks 41 are positioned in channels A and B in suilicient number to completely ll the same from 4end to end as indicated in Figures 1 and 2 and are moved longitudinally in the channels by the reciprocation of the pusher bars 21 and 28 and transferred from one channel to the other by transferring means which will now be described.

The distance that the pipe I'I and the cross heads which are attached thereto reciprocate at leach cycle of rotation is equal to twice the length of the blocks, for a reason which will hereinafter be pointed out. When the channels A and B are .full of blocks, the blocks willbe moved only the length of one block during each cycle of rotation for the reason that there is a lost motion at the point D Figure 23 equal to the length of a block. At the end of each cycle of rotation, the blocks are in the positions shown by full lines in Figure 1 and it is now necessary to move the lowermost block in channel B to the dotted line position at the lower end of channel A and to move the block designated by 41X at the upper end of channel A to the dotted line position in front of the pusher bar 21. To effect this transfer of blocks from one @channel to the other, certain mechanisms have been provided which have been shown in a more or less diagrammatic manner in Figure 23 to which reference will now be made. At the lower ends of the guide members and channels A and B there is a slide designated by reference numeral 56, which has a finger 51 pointing towards the blocks. This slide moves in a guide which has not been shown. A cable 58 is attached to one end of the slide and after passing over one or more pulleys 5S, terminates in la weight 6B. This weight tends to move the slide tothe full line position. Extending from the slide is another cable 6I that passes around the pulley 52 and is anchored to a stationary member at point 63.. An arm 64 is connected with the cross head 29 and carries a pulley 65 which contacts the bight of the cable, all as shown in full lines in Figure 23. When the cross head moves towards the left into the broken line position, the bight of the cable is increased and the slide 55 is moved into the broken line position. It will be seen that the slide 5,6 has a pro- `iection 66 and that there is a pawl 61 pivoted to a stationary part of the machine at 68. A spring 69 tends to rotate the pawl in a clockwise direcltion. When the slide reaches the broken line,

the projection 65 will pass by and engage the hook at the end of pawl 51 and the slide will therefore remain latched in this position until released. The release of the slide iseffected by means of a pin 'IIJ that is carried by arm 64 and which engages the pawl and moves it to releasing position just before the cross arm reaches the return end of its stroke. When the pawl releases the slide 56, it will move in response to the tension produced by weight 60, thereby engaging the lowermost block in channel B (Figure 1) and move this block to the full line position in channel A.

At the upper end of the machine the block 41X must be moved to the dotted line position in channel B and this is effected by means of a transfer mechanism comprising a slide 1I that moves in a suitable guide, not shown, and to which nger 12 is pivotally connected at 13. A spring 14 tends to hold this linger against the stop 15. A cable 16 is attached to the slide 1I and after passing over one or more pulleys 11, is attached to a weight 18. In the full line position shown in Figure 26, the weight is at its uppermost position. It will be observed that the cross head 25 has an arm 19 to the end of which 'a pulley SII is attached. A cable 8| is attached to the slide 1| and after passing around the pulley 82, is anchored to a stationary part of the machine at 83. A bight of the cable passes around the pulley 80. When the arm 19 moves from full line to dotted line position, it permits the weight 19 to move the slide 1| towards the broken line position and in this movement the finger 12 engages the side of the block 41 shown in broken lines and transfers it to the broken line position in channel B. When the slide reaches this position, the cross head and the attached parts are in the broken line position. An arm 84 is attached to the cross head and carries a downwardly extending plate 85 on one side. A lever 86 is pivoted to arm 84 at points 81 and is acted on by a spring 88 which tends to move it in a counterclockwise direction about the pivot 81. The free end of the lever has a downwardlly projecting curved plate 89 that overlaps the corresponding side of a block as shown in Figure 23. With the parts in the position shown in Figure 23, it is apparent that if the arm 84 begins to move towards the left, it will carry with it the block 41 that is positioned between plates 85 and 89. When the parts move towards the leit, the end block in channel A will be separated from the next block and will be carried a distance of its own length before the pusher bar 28 will engage the lowermost block in channel A. After this, the whole row of blocks in channel A will move the length of one block. Due to the lost motion above referred to, the upper block in channel A will move twice its own length, while the other blocks in this channel will lmove only their own length and as a result of this there will be a space indicated by Y in Figure 23 that is equal to the length of a block. There is a solid plate 90 that extends beyond the upper ends of guides Il and I3 for the support of the blocks and this is provided with an opening 9| through which the balls drop after they are removed rom the molds.

It is apparent that the separating device comprising .the lever 88 and associated parts must be released as the parts approach the end of their stroke and to effect this a stop 92 is positioned in the path of the upper end of lever 86. The action of this stop is to move this lever to the position shown in broken lines. It is further apparent that some means must be provided for holding this lever in inoperative position until the parts return to a position in which another block is to be grasped and this is effected by means of a friction brake mechanism comprising a lever 93, which is pivoted at 94 and has an end 95 bent so as to engage the lever 86 and hold it against movement due to the action of spring 83. The pivotal connection at 94 is such that it offers a considerable frictional resistance against movement and this is effected by any one of the many well known means employed for this purpose in dierent types of machines. A stop 96 is so positioned Ithat when the parts approach their lowermost limit of travel, the two levers 86 and 93 will engage this stop and this will remove the end 95 from lever 86 and permit the spring to function so as to bring the part 89 into block engaging position. The parts are now in such a position that at the beginning of the next cycle of rotation, another block will be separated from the line of blocks in channel A and moved to a point on the upper side of opening 9|, whereupon the ball casting in the mold can be separated and allowed to drop through the opening 9| from 8 to a tumbling barrel 98 which is rotated by suitable means.

From the above description it will be apparent that with the mechanism illustrated, an intermittent shifting of the mold blocks can be effected, the blocks being periodically moved in their channels the length of one block and the upper block of channel A being moved the length of two blocks so as to eiect a separation for the purpose of removing the castings. So long as air is supplied to the cylinder 3|, this movement will continue. The pipe supplying air from the storage tank to the three-way valve has not been shown, but it is provided with one or more valves positioned at strategic places around the machine so that the operator can stop the machine whenever he Wants to by closing any one of these valves.

The pressure exerted by the pusher bars in moving the blocks upwardly in channel A serves to force the contacting surface of adjacent blocks towards each other .to close the mold. The adjacent block surfaces do not necessarily have to be finished, but can be in the condition in which they arrive from the mold, because any molten metal that penetrates the thin space between these blocks will immediately become chilled and seal the mold.

Since it is the purpose of this machine to make balls or other similar articles, it is necessary to provide molten metal and to deposit this in the grooves 40 where it may run downwardly and enter the gates and fill the molds. In Figure 2, a ladle 99 has been shown. This is supported on trunnions |00. The carriage for the ladle has not been illustrated as any of the ordinary and well known ladle supports can be used. The pouring lip of the ladle has been designated by reference numeral |0|. Molten metal is poured from the ladle into the groove 48 and runs downwardly from one block to .the other and sincethe gates 50 intersect the grooves 48, molten metal will flow through the gates and into the mold depressions, lling the same. Due to the fact that the gates are positioned to one side of the groove, the metal will 'be given a rotary motion as it enters the gate opening. This rotary motion provides the metal sprue, with a center opening like that indicated by reference numeral |02 in Figure 3 where the sprue has been designated by reference numeral |03. The opening in the sprue permits any air or gas to escape and after the mold has been completely filled, opening |02 will also close. The rotary motion of the molten metal has been designated by arrow 84 in Figure 14. The different sprues are connected from one block to the other by means of the strips of groove metal |05. L

Since the groove metal must be separated or broken before the blocks can be separated, means has been provided to notch the metal and to sub'- ject it to a chilling action to make it brittle. For the purpose of notching and chilling the groove metal, a wheel |06 has been mounted for rotation about a bearing |01 that is carried lby the iront end of an arm |08 which in turn is pivotally connected at |09 to the vertical flange l0 of an angle bracket whose horizontal flange I is secured to the `guide I3 by means of blots H2. The wheel |06 is provided with sharp steel teeth or projections ||3 that are adjusted to travel in the grooves 48. This wheel is positioned directly above the point where the metal is poured and therefore engages the groove metal before it hardens. The teeth cut depressions ||4 in the groove metal in the manner shown in Figure 11.

whence it passes through a tubular conduit 91 75 By the time the molds reach the upper end of such an extent that it will be very brittle and can be readily broken at points IM. In order to expedite the cooling of the groove metal a massiv-e metal wheel I I is mounted on a support like that employed in connection with wheel |06 and positioned so as to engage the upper surface of the groove metal for the purpose of abstracting heat therefrom. Due to the heat absorptive action of the mold blocks and to the further heat absorp-v tive action of Wheels |06 and I I5, .the groove metal will cool very rapidly so as to be entirely solidiiied at the upper end of channel A.

blocks on opposite sides of their center lines. I

For the purpose of making these springs effective to rock the blocks, the latter has been constructed with their bases in a broadly convex shape. The convex curvature is effected by three straight surfaces comprising a center straight surface F and two upwardly inclined straight surfaces G, as shown in Figure 18. The center surface F rests on the upper surface of the bottom members I4 and I5 so as to be in good heat transmitting relation thereto. The upper surfaces of these blocks are provided with short transversely extending ribs II8, the ribs on opposite sides being staggered. When one of these ribs passes under the end of a spring, the pressure exerted by the latter will rock the block and this rocking of the block While the metal is still soft, results in a loose connection between the casting and the mold which facilitates the removal of the casting.

Where the rocking mechanism is dispensed with the blocks .may have flat bottoms as shown in Figures 5 and 10.

In order to break the groove metal, the rupper surface of bottom member I5 is provided with an upwardly convex portion like that designated by `reference |numeral I I9 in Figure 20, located a short distance above wheel II5 where the metal is brittle after having been notched and chilled. When the blocks are moved in the direction of the arrow, they are first turned upwardly so as to bend the groove metal at point H and this, due to the brittle condition of the metal, tends to weaken it and break it and this is further augmented at the next joint. As the blocks pass over the hump the groove metal will be put under tension which completes the breaking thereof.

In Figures 21 and 22, different arrangements of the blocks have been shown. In Figure 21, the groove 48 is positioned to the outside of channel A and in 22 the groove is positioned towards the inside of channel A.

The amount of cooling can be adjusted by varying the position at which the metal is poured with respect to the length of the row of blocks. It is evident that the nearer to the top of the row the metal is poured, the shorter time it will have for cooling and this makes it possible to give the castings the best possible heat treatment to obtain the optimum grain structure.

By increasing or decreasing the amount of metal in the mold blocks with respect to the siZe of the balls or other castings, and by substituting copper or a suitable alloy, the amount channel A, the groove metal will have cooled to '10 ,of chill and the resultant grain structure can be modified within reasonable limits.

Due to the fact that the molds are separated at the upper end of the row in channel A, the 'operator has an opportunity to employ a hammer or a chisel or any other suitable tool to .loosen the casting from the mold in case it should not fall out of its own accord.

The sprues H33 become quite hard and brittle due to the chilling action and are easily broken at their narrowest points and may be provided with a restricted area at this point, as indicated by reference numeral |20.

In the present embodiment the mold blocks have been shown and described as made from cast iron and in Figure 8 a block having a copper insert 52 has been shown. Its use is contemplated where a Very rapid chill is desired.

Since the blocks are arranged in rows and are moved by means of pressure exerted on an end block, it is evident that the blocks are free to expand and contract in response to temperature changes.

In addition to the spring 34 and. as a further V and an adjustable means for returning the cross head 29 and associated parts, a weight Wt may be attached to the cross head and connected with the latter by a cable in such a manner that the pull due to the weight will supplement the force exerted by the spring. This weight may 4be increased or decreased to effect the proper operation with diiferent inclinations of the machine.

Attention is called to the fact that when the mold blocks are heated due to their contact 4with the molten metal, the latter has its temperature decreased and the groove metal Ais therefore contracting at the time the blocks are .expanding and since the groove metal cools fast 40l nthe action of the notching wheel IIlI.

In the construction shown and described, the mold blocks are readily removable as they merely rest on the bottoms of the channels. A block v.can .be removed at any time and replaced by another without aifecting the operation.

Referring again to Figures 9 and 10, attention is called to the fact that the mold block 4'I can be made from copper and the top 54 from cast iron. Since copper is. a much better conductor of heat than the iron, the same relation between the heat conductivities of the two parts will be preserved.

Attention is directed to the fact that in the construction shown and described, the molds are pushed upwardly along an inclined path by a force applied to the lowermost mold in the row and this allows for expansion and contraction in response to temperature changes and as a result the molds are always held in contact with a constant force during the entire range of temperature variation.

Having described the invention, what is claimed as new is:

1. A ball casting machine comprising, in combination, an elongated frame, inclined at an angle to the horizontal, having its upper surface provided with two spaced parallel guide channels, a row of mold blocks positioned in each channel, in end contacting relation, said blocks having their contacting surfaces provided with complementary mold depressions and gate openings and a channel in their upper surfaces connecting said gate openings, a power reciprocated member having one abutment for intermittently moving the mold blocks upwardly in one channel and a second abutment for moving mold blocks downwardly in the other, each reciprocation moving the rows of blocks the length of a block, reciprocating transfer mechanism at the lower end of the frame for moving blocks from the lower end of the downwardly moving row to the lower end of the upwardly moving row, means for filling the molds in the upwardly moving row with molten metal, means for separating the uppermost block in the upwardly moving row from its adjacent block to permit the casting to be removed, and a second reciprocating transfer mechanism for moving the separated block in the upwardly moving row to the upper end of the downwardly moving row of blocks, whereby an intermittent circulation and separation of the blocks is effected.

2. An automatic ball casting machine in accordance with claim 1 in which a groove metal connection is formed which connects a row of several spaced gates and in which means comprising a toothed wheel positioned for rotation with its teeth projecting into the groove metal, is' provided for chilling and at least partially severing the groove metal to facilitate breaking thereof.

3. An automatic ball 'casting machin-e in accordance with claim 2 in which the bottom of the channel containing the upwardly moving blocks is provided with an upwardly convex portion positioned above the chilling and severing device for bending the groove metal to effect a breaking thereof.

4. An automatic ball casting machine in accordance with claim 1 including means for effecting a relative movement of the blocks with respect to each other while the metal is setting to facilitate removal of the castings from the molds.

5. An automatic ball casting machine in accordance with claim 1 in which the under surface of each block is transversely convex and in which means is provided for effecting a rocking movement of each block relative to its adjacent 12 blocks while the metal is setting,A whereby the removal of the casting is facilitated.

6. An automatic ball casting machine in accordance with claim 1 in which the sides and bottom of the guide channels are formed from hollow members through which water may be flowed for effecting a cooling of the blocks, the hollow members at the sides being a xed distance apart throughout their length and the hollow member at the bottom extending between the lower edges of the hollow members at the sides to form a channel with a closed bottom and an open top, the channel being of such size that a row of blocks may slide therein with the sides of a block in engagement with the hollow members at the sides, and the bottom of the block in engagement with the hollow member at the bottom.

7. An automatic ball casting machine in accordance with claim 1 wherein the channel in the upper surfaces of the molds is disposed relative to the gate openings in a manner to effect rotary movement of the molten metal as it ows down a gate open-ing.

WILLARD C. BRINTON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 5,371 Campbell Nov. 20, 1847 533,139 Potter Jan. 29, 1895 891,891 Weston June 30, 1908 972,108 Herbert Oct. 4, 1910 1,139,885 Mellen May 18, 1915 1,319,674 Stephenson Oct. 21, 1919 1,863,371 Greene June 14, 1932 1,864,270 Eurich et al June 21, 1932 1,984,385 Sherwood et al. Dec. 18, 1934 1,996,905 Davis et al. Apr. 9, 1935 2.091,348 Baldwin Aug. 31, 1937 2,308,448 Hodge Jan. 12, 1943 2,322,795 Enderich et al June 29, 1943 2,326,164 Payne Aug. 10, 1943 2,369,233 Hopkins Feb. 13, 1945