US1062289A - Apparatus for making castings. - Google Patents

Description

ITED ,y sTATEs PATENT oFFICE.

DAVID MAXWELL, OF DETROIT, MICHIGAN, ASSIGNOR TO THE LIQUID FORGED S'IEEL CCMPANY, or CLEVELAND, oHIo, A CORPORATION APPARATUS RoR MAKING CASTINGS.

Specification of Letters Patent. n

OF OHIO.

. I Patented May 20, 1913.

Original application filed JanuaryB, 1911, Serial No. 601,742. Divided and this application led March 9,

1911, Serial No; 613,391. Renewed October 4, 1912. Serial No. 723,999. 1

l o all whom it may concern Be it known that I, DAVID` MAXWELL, a citizen of the United States, residing at Detroit, in the county of Wayne and State of Michigan, have invented certain new and useful Improvements in Apparatus` for Making Castings, of which the following is a. specication.

This invention relates to the art of casting, and while applicable to the making of castings in general, is particularly designed for use'in making ingots, and has for its object to prevent piping and segregation` and to enable the stripping of a casting upon one and the same apparatus.

With these and other objects in view, the present invention consists in the combination and arrangement of parts as will be hereinafter more fully described, shown in the accompanying drawings and particularly pointed out in the appended claims, it being understood that changes in the form, proportion, size ,and minor details may be made within the scope of the claims, without departing from the spirit of the present invention.`

In the drawings,-Figure 1 is a vertical central longitudinal sectional view of one form of apparatus for practising the'invention. F ig'. 2 is a similar view of another form of apparatus for applying the impacts ina differentv manner from that of Fig. 1.

' ,Fig 3 is a reduced plan view, partly in section, showing the manner of guiding the hydraulic or adjustable piston shown inl F ig. y1. v

Referring at first to Fig. 1 of the accompanying drawings, l designates any su1t able base or bed from which rises a cylinder.. 2 having.an open top through which works'a piston 3 suitably packed, as at 4.

Water is admitted into the bottom portion of the cylinder 2 through a suitable port 5 formed through the bed or base 1 or located at any other suitable point as may be desired. The bottom of the piston 3 is pro-y vided with Aa central dependingboss 6 designed to strike the basey orbed 1 so as to ort the bottom of the piston slightly the bed or bottom 1 to provide a space to receive the water initially introduced into .the cylinder. It will of course be understood lthat the exhaust from -the cylinder passes out through the port 5. The piston 3 is hollow or provided with a central longitudinal bore 6 opening through the top of the piston. Working in the bore of the piston is a plunger including a stem .or shank 7 of `somewhat less diameter than that of the bore of the piston.- This shank is provided at its lower end with a piston head 8 suitably packed and working in ,the cylinder formed by the hollow piston 3.' At the upper end of the stem 7 there is a striking head 9 designed to applyimpacts to the casting as will be hereinafter explained. The top of the cylinder 3 is provided with a suitable gland l0 through which the piston shank or stem 7 works. For the support of an ingot above thestriking head 9 there is provided a table or platform 11 supportedor loosely connected to the table or platform 11 by means of eyes'17, each hook being designed to be engaged with a suitable ear or lug`18 as commonly provided upon ingot molds.' In order to insure a snug engagement betweenthe hook and adjacent lug or ear a wedge 19 is driven in between the hook and ear. By the means just described, a mold may be very conveniently and rigidly held against'the casting plate so as to avoid displacement by the blows imparted by the striking head 9 of the reciprocating plunger 7. In the top of the casting/plate 14 is a central depression or seat 20 of suitable shape vcorresponding' to the cross sectional shape of the lowerendof the casting. A downwardly tapered opening 22 extends through thelcalsting plate from the seat or socket `20, with its lower yopen end registering with an opening 23 extending through the table or platform l1' in alinement with the striking head of the reciprocating plunger. Workinginthe openings 22 and 23.

and conforming to the shape thereof is an impacting and stripping head 24:, the low r lend '.of which is in the path of the striking For the automatic control of the percussive piston there is provided a valve chest 27 carried by the cylinder 3, there being upper and lower ports 28 and 29 communicating between the valve chest 27 and the bore of the cylinder 3. The valve in the chest 27 is controlledby suitable tappet mechanism including a rocker arm 30 and upper vand lower reciprocating tappet elements 31 and 32 arranged to coperate with the striking hea-d 9 and the rocker arm 30. The lower tappet member is mounted in a suitable guide'33 carried by the top of the adjustable cylinder 3, while the upper tappet member works in a guide 34 carried bythe table or platform 11. The striking head 9 of thepercussive piston is provided with upper and lower beveled portions 35 and 36 coperating with the respective tappet elements 31 and 32 to l slide the same'back and forth and thereby kthrow the rocker arm 30 to .shift the valve inthe valve chest 27. Forthe purpose of guiding the adjustable cylinder 3, the head of the cylinder, as best shown in Fig.' 3 of the'drawings, is provided in its outer edge with notches or recesses 3', each of which receives one of the standards 12, whereby the cylinder 3 is guided in a vtrue Vertical direction during its up and down movements. In practising my invention by means of the apparatus herein shown and described, molten metal is poured into theI mold through the open top thereof, and after a suitable quantity has collected in the bottom of thel mold, depending upon the character of the metal under treatment, air or other compressible iuid `under pressure is admitted into the bottom of the cylinder 3 through the port 29 so as to drive the percussive piston upwardly to strike the reciprocating impacting head 24 andtherebyapply an impact directly against the ingot 26.

I When the percussive piston reaches its upper limit by striking the bottom of the reciprocating head 24, the tappet 31 will have been moved outwardly ,to its limit bythe striking Ahead 9 wiping across the ends of the tappet,

whereby the rocker-arm 30 will be thrown and the valve in the valve chest 27 reversed so as to admit air-.through the port 28 to force the percussive piston downward, during which time the port 29 is an exhaust porti When the percussive piston 7 reaches its downward limit, it will actuatey the tappet member 32 to return the valve in the valve *chest 27 toits original'position, whereupon air will beadmitted beneath the piston head 8 -and the percussive piston again driven upwardly. By this means, a succession of 1mpacts may be very conveniently and eifec- -tively applied directly to the metal in the mold. The `effect of the impact or jars upon the. metal is such as to-cause the metal to pack convergently downward along the longitudinal axis of the casting, whereby secondary pipe is effectively prevented. In the initialimpacting operation, the apparatus/is controlled so as to impart a vibrating Ior trembling motion to the molten metal for the purpose of maintaining the metalloids in suspension'. As the level of the molten metal gradually rises in the mold, this trembling or vibration of the molten metal is kept up in order that the 'metalloids may always be in suspension4 throughout the successive levels of the molten metal during the pouring operation. By thus maintaining the metalloids suspended, segregationJ is efl'ectually prevented. As the level of the molten metal rises in the mold it becomes necessary to increase the impact, depending upon the character ofthe metal under treatment. To

effect this change in the character of the im- 'pact all that is necessary to do is to lower the adjustable cylinder 3 by permitting vwater to escape through the port 5, whereby the-stroke of the percussive piston will be increased and the power of the impact correspondingly increased. When the level of the molten metal reaches the upper port-ion of the mold where there. is a tendency to form bridges, hanging walls and piping, the power of the impacts is materially increased for the purpose of breaking d'own any hanging walls, bridges and crust which form or .tend to form at the upper portion of the casting. By thus breaking down the bridges, hanging; walls and crust, the broken portions are thrown into the molten portion and are. remelted therein, whereby bridges and piping are eiectually prevented and the x top of the metal is maintained in a molten condition except for the annular freezing at the inner walls of the mold.

From the Iforegoing description' of the operation, it will be understood that the impacts are quick and relatively light during the initial pouring of the mold and, as the level of the molten metal rises, the character of the impacts is varied by increasing the length lofthe stroke of the percussive piston and decreasing the rate thereof, the

heaviest blows being struck during the pipey forming and bridge-forming periods.

After pouring, and forthe purpose of preventing the molten metal' from splashing out 'through' the open top o-f the mold and also to retainl heat, I employ a' cover 37 which ts loosely within the open top of the mold `and floats upon the molten metal. This cover preferably is in the form of a spidered casting filled with some suitable refractory or infusible material 38 forming a facing for the lower side of the cover to come in direct contact with the molten metal. By the use of this cover, oxidation of the upper surface of the molten metal is prevented and the metal is maintained in a molten condi,- tion for a relatively long period.

Due to shrinkage of the metal, a cup will be formed in t-he top of the casting containing some molten metal. This cup may be filled up bythe addition of molten metal, the cover replaced and the impacts continued until the metal in the cup portion of the casting has become solidified. When the additional molten metal is poured into lthe' cup portion a violent'eruption is produced by reason of the very hot metal mingling with the relatively cooler met-al, whereby all the impurities inthe molten metal contained in the cup will rise to the. surface, and the molten metal -will solidify and unite to the walls of the cup and thus render the casting homogeneous-clear to the top thereof.

After the treatment of the lcasting has beencompleted, the adjustable cylinder 3 is elevated to its limit, and yhydraulic fluid pressurev is admitted beneath thebottom of the percussive piston to force the same slowlyupward, whereby the solidified ingot will be stripped upwardly through the mold which is held down by thevhooks 16, until the top of the ingot can' be caught bya crane and pulled entirely out of the mold. yAs soon as an ingot has been stripped from the mold, it is of course apparent that the latter 4can be immediately poured and the'treatment of the ingot proceeded with in the manner hereinbefore described. In other words, a single mold servesfo'r successive castings and need not be removed from the impacting apparatus until, it has become yunserviceable.

Instead of applying theimpacts directly to the material in the mold while holdingl the mold fixed',l the mold and its contents may be lifted up and dropped so as `to apply impacts to the metal. This manner of applying impacts may be carried outby an apparatus vsuch as shown in Fig. 2 of the l accompanying drawings wherein 39 desig nates a suitable base upon which issupported an upright cylinder 40 containing a piston vor plunger 41 working through the n `cast-ings while solidifying, including a reciprocating impact member, Huid actuated' head 42 designed to support a casting under treatment. Where it is an ingot that is be- 'treated the usual casting block 43 is plcedupon the head or table, and the ppen ended ingot mold 44iis placedupon the casting plate. in the usu'al manner. Impacts are 'applied rto the casting bytadmitt-ing uid i pressure into the bottom of the cylinder 40 through a suitable port 5 and afterwardk exhaustingthrou'gh this port so as to `drop the cylinder andthe table or vhead carrying y the mold.. With this type of apparatus, the impacts are not applied directly to the metal in the mold independently of the mold while the'latter is4 held fixed orfstationary, as in'." Fig. 1 of the drawing, but the mold and its contents are lifted up-and then dropped.

The cylinder 40 isl provided withports or openings 40 normally closed by the plunger 41 so as to prevent the escape ofiuid pressure in the cylinder 40, but which operate as escape ports in the event of the plunger 4l beingele-vated above suchports, thereby tol prevent excessive elevation of the plunger.

, It will of course be understood that a floating cover 37 is employed as hereinbefore explained in connection with Fig. 1.V The admission and exhaust of Huid pressure to the cylinder is effectedby means of a valve chest 46, the valve of which is controlled by a coni necting rod 47 extendingbetwe'en, the valve in the chest and the head or table on the top of the piston. Any suitable or preferred meansl may be employed for adjusting the rod 47 to vary the. throw oft-he valve for the purpose of increasing the stroke of the pist-on and for increasing the rate thereof.

In using either form of apparatus for carrying out the method, the mold may be'I- used with its small end uppermost -or yits large end uppermost as may be desired, and the effects of the two machines on the metal in the* mold are identical.

v This application is a division of my copendingl application Serial No. 601,742, filed January 9, 1911. 'l

What is claimed is loo 1. An apparatus for applyingimpacts'tol castings while slodifying including a'recip rocating impact member, fluid actuated means for rcclpiocating said member, and

4meansfor automatically controlling the fluid-actuated means. .v

2. A apparatus for applyingv impacts to f castings while solidifying, including an impact member, fluid actuated means for reciprocating the impact member,`means actuated --by a moving part of the impacting `means for'controlling the supply andA` dismeansfor` reciprocating vthe impact member,

means actuated by moving art of'the impacting means for 'controlling the supply and discharge of fluid pressure and means to vary the stroke of the fluid actuated means vvithoutstopping the operation of the apparatus.

4c. An apparatus for applying impacts to cast-ings vvhlle solidifying, including a reciprocating impact member, fluid actuated means for reciprocating the impact member,

means actuated by a movmg part of the imlpacting means for controlling the supply and discharge of fluid pressure and means for varying the rate of operation off the fluid actuated means Without stopping the operation of the apparatus.

5. An apparatus for applying impacts to castings While solidifying, including a reciprocating impact member, fluid actuated means for reciprocating the impact member, means actuated by a moving part of the impact-ing means for controlling the supply and discharge of fluid pressure and means for varying the stroke and rate of operation of the `luid actuatedmeans vvithout stopping the operation of the apparatus.

6. An apparatus for applying impactsto castings Whilel solidifying, including a support for a mold, means to apply impact-s to the contents of the mold independent of the mold, and means actuated by a Imoving part of the impacting means for controlling the supply and discharge of fluid pressure.

7. An apparatus for applying impacts to castings While solidifying, including a support for a mold, fluid actuated means for applying impacts to the contents of the mold independent of the mold, and means actuated by a moving part of the impacting means for controlling the supply and discharge of fluid pressure. v

8. An apparatus for applying impacts to castings while solidifying, including a support for the mold, fluid actuated means for applying impacts to the contents of the mold independent of the mold, including a percussive piston for applying the impacts, and means actuated by a moving part of the impacting means for controlling the supply and discharge ci fluid pressure.

9. An apparatus for applying impacts to cast-ings While solidiying, including a supfit within the mold and float upon its contents and exclude air and means for applying impacts to the casting.

10. An apparatus for applying impacts to castings While solidifying including a support, a mold .having an open t-op, a cover to Y fit Within lthe mold and float upon its contents and exclude air, and means for applying impacts to the bottom of the casting.

11. An apparatus for applying .impactsto castings While solidifying, including a supfor a mold, fluid actuated impact4 port U l means for applymg impacts to the contents of the mold independent of the mold, in-

cluding a percussive piston for applying un- -cast-ings While solidifying, including a suport a mold having an open top, a cover to pacts, and means actuated by a' moving part of the impacting means for controlling the supply and discharge of Huid pressure.

12. An apparatus for applying impacts to port for a mold, fluid actuated impacting means for applying impacts to the contents of the mold independent ofthe mold, including a percussive piston Jfor applyingl impacts, and means actuated by the movement of the piston for controlling the supply and discharge of fluid pressure.

13. An apparat-us for applying impacts to castings While solidifying, including a mold support having an opening therethrough, an

impacting plunger Working in said opening,

and fluid-actuated impacting means including a percusslve piston 1n operative relation with the 'impacting plunger.

14. An apparat-us for applying impacts to castings While solidifying, including a mold support, an impact plunger Working through the support, means for securing a mold to the support with its open end in alinement with the plunger, and fluid actu-y ated impact applying means including a percussive piston in operative relation with the plunger.

15. An apparatus for applying impacts to castings While solidifying, including a mold support., fluid actuated impact. applying means including a cylinder and a percussive piston, and a fluid pressure cylinder containing the cylinder of the impact applying means.

1G. An apparatus for applying impacts to the castings While solidifying, comprising a -mold support, a stationary fluid pressure cylinder below the support, and fluid actuating impacting means including a cylinder adjustably supported in the stationary fluid pressure cylinder, and a percussive piston Working in the adjustable cylinder.

17. An apparat-us for applying impacts to castings While solidifying, comprising a mold support, a stationary fluid pressure cylinder beneath the support, and fluid actuated impact applying means including anadjustable cylinder adjustably supported Within the stationary cylinder, a percussive 115 piston Working in the adjustable cylinder, a l valve for controlling the supply and exhaust of the adjust-able cylinder, and valve controlling means including tappets carried by the mold support and the adjustable cylinder respectively in cooperative relation with the percussive piston.

'pacting means lfor controlling the supplyI and discharge of fluid pressure.

19. In apparatus for makingtcastings, a

`combined impacting and stripping member, Tating means to move` said member for stripmeansA to reciprocate said-member forjimping.v

10 pact-ing', and other means for moving said In testimony whereof I affix my signature memberfor stripping. inpresence of tWo Witnesses.

20, Inapparatus for making foastings', al DAVID MAXWELL. combined impacting; and strippil'igmember, Witnesses:

vfluid actuated means to reciprocate said. WALTJizR S.

member for impacting, and other `lud actu- EDNA HoWAitD.

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