Means for cooling permanent metal molds

Application filed May 4, 1922.

Serial No. 558,396.

To all whom it may concern:

Be it known that I, De Forest W. Candler, a citizen of the United States, residing at 2932 West Grand Boulevard, Detroit, in 0 the county of Wayne and State of Michigan, have invented certain new and useful Improvements in Means for Cooling Permanent Metal Molds, of which the following is a specification.

io The object of this invention is to provide means for cooling permanent metal molds when used for the continuous production of iron castings. The novel feature is the means provided whereby the cooling fluid, IS preferably air, is intermittently admitted to the hollow molds, the advantages of which are that the codling fluid is used economically, and, what is more important, should a crack develop in the face of the permanent 20 mold there will be no pressure of the cooling fluid within the mold during the casting operation so that the casting will not be spout by the escape of the coding fluid through the crack as the escape of cooling fluid would 2® cause a depression in the surface of the casting.

An additional object of this invention is to produce soft gray iron castings by avoiding increasing the cooling rate of the molten 30 iron (which produces hard castings) during the period the molten iron is solidifying in the mold. .

Figure I shows a sectional elevation of a molding machine to which the air cooling 35 device has been applied.

Figure II shows diagrammatically in plan the means whereby the cooling fluid is distributed to the various hollow molds.

In Figure II, A' and A are the legs for 40 supporting the base, B is the base, C is the driving shaft which rotates the turret D, E is a horizontal rod projecting from the turret which supports the hollow molds F and G, H is a projection of the driving shaft 45 C. _ The shaft H carries a pasting K, to which it is connected, whereby the piece K is rotated with the turret D, Z is a pipe entering K and supplies the cooling fluid. The pipe Z is supported by the stationary elbow 50 X which in its turn is supported by any convenient means. The pipe Z fits inside the casting K and leakage of the cooling fluid is. prevented by means of the gland Y. The pipe Z, which is stationary, is provided with 55 a port J through which the cooling fluid is distributed. The casting K is provided with outlets L and M into which are threaded BN and Ο. P and Q are preferably le rubber hose leading from the pipe O to the molds F and G, the cooling fluid eo being admitted to these hollow molds F and G at the bottom and escaping at the open ports R and S at the top.

In Figure I, which is a plan view of the means for distributing the cooling fluid, T 65 and U are outlets corresponding to the outlets L· and Μ. V and W are pipes threaded into the outlets T and U.

Operation.

The operation of the molding machine itself is described in my co-pending application, Ser. No. 504,988, filed October 3, 1921, which discloses the manner in which the molds F and G are separated and the cast- 75 ing ejected, which is not the subject of the present invention. Immediately after the casting is ejected the cooling fluid is admitted to the hollow cast iron permanent molds F and G from the elbow X through so the valve K and the pipe O and its outlets P and Q. The pipe Z is so adjusted in the elbow X that the outlet J comes opposite the opening leading to the pipe O in the casting K just after the casting is ejected 85 from the molds F and G. Immediately before the molten iron is poured into the molds F and G, after they have come together once more, the opening J ceases to connect with the passage O, so that the air no longer flows 60 through the mold. By thus cutting off the flow of cooling fluid just prior to the pouring of the iron in the mold it appears that the quantity of air used is conserved. However, what I have found is of more impor- 96 tance is that in the event there are any small cracks or leakages due to porosity in the mold, then if the air pressure is allowed to remain in the mold during the casting operation itself, the escape of the cooling air or 100 other cooling fluid through the cracks in the mold will spoil the casting and cause other trouble which will be obvious to any one familiar with the molding art.

I have found that compressed air, at 15 105 to 25 pounds per square inch, is the most convenient cooling medium to use, as comparatively small pipes will supply sufficient cooling fluid so that the escaping air will not exceed 700° F., under which condition no a

1,499,017 the cast iron molds will stand up indefinitely even with molten iron at 2700° F.

In order to provide means for cooling E and E', the horizontal rods upon which the molds F and G are mounted and which serve as guides on which the molds F and G slide back and forth as the molds are opened and closed during the casting operation, as described in my co-pending application, Serial No. 504,988, referred to above, and hollow passages 1 and 2 are provided through the center of the guides. E and E'. These hollow passages connect with the hollow bosses 3 and 4, which support the guides E and E'. Into the hollow bosses 3 and 4 Y pipe fittings 5 and 6 are connected by pipe connections, as shown in Figure II. This pipe 5 is connected by a pipe fitting 6 to the rotating valve K and an inclined passage 7 connects this, pipe 5 with the interior of the air entrance pipe Z. In Figure la corresponding pipe is shown leading to the period, opposite set of mold guides. The air flow- * ^T~ ing through the guides E and E' prevents i the lubricating oil caking and reduces the power necessary to drive the machine.

What is more important, however, is the fact that there is a considerable quantity of heat dissipated during the casting opera' tion. This neat causes the guides to distort leading to said hollow mold whereby the 55 flow of cooling fluid is automatically cut off during the pouring period. ....

3. In a rotating casting machine in which castings are successively poured and ejected at each revolution of the casting machine, eo a plurality of hollow metal molds, a stationary pipe supplying cooling fluid under pressure to said hollow molds, a rotating valve associated with said pipe, a plurality of outlets from said valve leading to said 55 hollow metal molds whereby the flow of cooling fluid is successively cut off from each hollow mold during the pouring period.

4. In a rotating casting machine having a permanent hollow ironmold., a pipe supply- 79 ing air under pressure to said.hollow mold, a rotating valve associated with said pipe, an outlet from said valve leading to said hollow mold, whereby the flow of air is automatically cut off during the pouring 75

5. In a rotating casting machine in which castings are successively poured and ejected at each revolution of the casting machine, a, hollow metal mold, a, stationary pipe sup- 80 plying air under pressure to said hollow mold, a rotating valve associated with said pipe, an outlet from said valve leading to said hollow mold whereby the flow of air is automatically cut off during the pouring 85 period. .

6. In a rotating casting machine m which castings are successively poured and ejected at each revolution of the casting machine, a plurality of hollow metal molds, a stationary pipe supplying air under pressure to said hollow molds, a rotating valve associated with said pipe, a plurality of outlets from said valve leading to said hollow metal molds whereby the flow of air is successively cut off from, each hollow mold during the pouring period.

7. In a rotating: casting machine having a plurality of permanent metal molds, slidably mounted upon rotating guides, hollow passages within said guides, and. a plurality of pipes conveying cooling fluid to said passages within said hollow guides, , for the purpose described.

In testimony whereof I affix my signa[ ture.

De FOREST W. CANDLER.

tion. This heat causes the guides to distort and in order to get continuous operation cooling is not only desirable but necessary.

By admitting the cooling air after the casting has solidified the cooling rate of the iron is not increased and therefore the tendency for the cast iron to solidify as white iron is minimized, and the tendency for gray iron to form is assisted.