US1602987A - Method and appabatus fob casting in closed molds - Google Patents

Description

Oct. 12, 1926. 1,602,987 H. P. MAUGHLIN METHOD AND APPARATUS FOR CASTING-IN CLOSED MOLDS Filed Sept. 6, 1922 2 Sheets-Sheet 1 I 7 W WINVENTOR. I

3 2 I Fig. 2.

ATTORNEY.

H. P. MAUGHLIN METHOD AND APPARATUS FOR CASTING-IN 01,0521) MOLDS Oct. 12 1926.

Filed Spt. 6, 1922 2 Sheets-Sheet 2 Fig.5".

ATTORNEY.

-.Patented Oct. 12, 192 6.

i HARRY r. manenmmor COLUMBUS, 01110.

I I ETHOD AND APPARATUS FOR CASTING- IN CLOSED 'MOLDS.

-, A Application filed September 6, 1922. Serial No. 586,513.

In the past, in casting it has been the practice to convey the'molten metal from the'furnace to the mold in open ladles, particularly when a sand mold was used. This method was disadvantageous, especially Where small, sharp and flawless castings. were desired, because the metal cooled, while transporting it, to such a' degree that it was sluggish and would not fill the mold properly. It also made it necessary to provide relatively large gates, which not only allowed impurities such as slag or dross to get intothe casting, but were difficult to remove, thus increasing the cost of the completed casting.

Furthermore, the height of the sprue determined the head pressure of metal in the mold and, if the volume or drop of the metal was too great, it would cause washing of sand into the casting causing flaws. When too small a sprue or gates were used, the

metal as it is poured into the mold and also the volume of flow and head pressure. This accurate control makes it possible to secure very small, sharp and flawless castings with verypmallgates,which can be easily and cheaply removed without ,damage to the casting. These small gates have a further important function in that they aid in keeping dross, slag and other impurities out of the mold, acting as a sort of strainer, thus reducing imperfect castings to a minimum. Another object of my invention is practically filling the mold at comparative y low velocity and lighthead pressure, to obviate the washing of sand into the casting or forcincreasing the metal is-sufiiciently high to flow freely.

- This will insure a casting that is sharp,

' clean cut and of full size.

A further object of myinvention has to do with clearing the pouring nozzle of the furnace of metal and preventing it from freezing therein.

Various other features 'of my invention will be apparent as this description progresscs and will be broughtout in the claims appended hereto. The various objects of my, invention are preferably obtained by the structure illustrated in the drawings, Whereinsimilar characters of reference desi gnate corresponding parts, and Whercin Figure 1 is a side elevation of my novel furnace and mold in their cooperative relation.

Figure 2 is a cross-section on line 2-2 of Figure 8 of my furnace nozzle in contact with the sprue plate of the mold.

my furnace 'ing in a closed mold is shown as comprising a substantially spherical furnace 1,'divided as at 2 for convcnience'in lining, and held together by suitable fastenings. The furnace 1 is provided with a charging opening 3, a

hinged cover 4, and a truncated conical projtiClJlOIl 5, whereinisheld the pouring nozz e 6.

The furnace is provided with a large hol low-trunnion 7, as best shown in Figure 6, haying an opening 8 for some suitable form of. heating unit for'melting the charge, and a small trunnion9 which is supported by the frame bearing 10. The trunnion 7 is supported by-rollers 11 carried in the bracket 12, which is in turn supported by the frame member 13. a ing-the 'mold apart, and afterward uickl'. the pressure to complete t efil ing of,the mold, while the temperature of.

Depending from the lower part of the furnace are wings 14. to which are. secured the track-like members 15. It is obvious that the furnace can be tilted about its horizontal axis and will carry the -t-rack-'like members 1'5 with it. To facilitate the tilting of the Figure 3 is a front elevation of the sprue pressure after the mold is 1 held a ainst tilting by the pins 36.

furnace I have provided the handle 16 fastened to the trunnion 7 of the furnace by the lug 17.

The furnace structure is sup orted in a horizontal position by a support ar 18, pivoted as at 19 to the frame 13, notched as at 20 to coact with the support rod 21 connecting the rails 15 near their outer ends. Adjacent the lower end of the support bar 18 is provided a foot 22 which coacts with the floor when in its disengaged position. It is evident that tiltin the furnace in a backward direction a su cient distance will raise the track 15 and release the support rod 21 from the notch 20 and allowing the bar 18 to swing outwardly and downwardly about its pivot 19 until the foot 22 stops further motion by coming into contact with the fio'or. The furnace structure can then be tilted forward to an desired position, the support rod 21 clearlng the bar 18.

Resting on the track members 15, I have provided a car 23 which supports a table 24 at an appreciable angle, as shown in Figure 1, by means of a ball and socket connection 25. Secured to the table 24 by suitable clamps 26 is provided a conventional flask 27 having a mouth-like sprue late 28, for the3sprue opening 29, clampe thereto as at O.

The ball and socket connection 25 allows a limited adjustment of the table 24 and flask 27, for the purpose of aligning the mouth-like s rue plate 28 with the pouring nozzle 6. The car 23 may then be moved toward the-'f urnace sufficiently to bring the mouth-like sprue plate 28 into cooperative relation with the pouring nozzle 6 as best shown in Figure 2.

It will be noted that the nozzle 6 fits the mouth-like sprue plate 28 with aball and the furnace by some suitable means such as shown in Figure 1, comprising upstanding bars 33 and a wedge-like block 34, which is forced between said bars 33 and the flask.

27 to hold the mouth-like s rue plate 28 thereof in coacting relation wit the nozzle 6. The upstanding bars 33 are vertically slidable in the channel structures 35 and Ialil'e e channe structures 35 are secured tov the track-like members 15 adjacent their outer ends. I have provided hook-like projections 37 near the uppgr ends of the bars 33 which allow of their ing lowered until the hooks 37 rest upon the upper edges of the channels 35, after the wed e 34 is withdrawn for the removal of the ask 27.

The level of the molten metal is held substantially on the line 38 by additions, from time to time, through the charging openin 3.

Tt will be evident that at times there is a possibility of metal freezing in the passage 39 of the sprue plate 28. To facilitate the removal of such frozen metal, I have divided the sprue plate '28 on the line 40. The two halves are held together by the bolt 41 and the nut 42 threaded thereto. 1 have also provided a dowel 43 which assists in hold- 311g the two halves in proper correlation to each other and in preventing any rotation of one half in relation to the other.

' The operation of my novel form of aparatus for casting in a closed mold is as ollows:

The molten metal being at proper temperature in the furnace, the mold is brought into proper cooperative relation and securely fastened. The handle 16 is raised, tilting the furnace backward until the su port rod 18 is released, whereupon the hen le is lowered with a continuous motion at a su1table speed through the position shown in Figure 4 and to substantially the position shown in Figure 5.

When the nozzle 6 becomes lower than the metal line 38, in the tilting operation, the metal fills the mold under a light head pressure, the flask 27 being substantially in a horizontal position as shown in Figure 4. The filling of the mold under light-head pressure is very important aslt obviates washing sand in the mold or swellin the casting due to the velocity of the meta and V yieldability of the sand. It therefore in-- sures against a swelled or enlarged casting. The continued tilting to the pos tion shown in Figure 5 brings a comparatively high head pressure to bear upon the metal in the mold while still in a liquid state, thus forcing it under pressure to completely fill the mold. Owing to the fact that the temperature of the metal can be controlled so closely the mold being in direct con unction with the furnace, the gate openings can be made much smaller than usual. This is important as it facilitates the removal of, the gates from the casting, thereby saving time and expense. The small gate openings have the further advantage of assisting in the prevention of slag, dross and sand from entering the casting as the mold is bein filled.

The furnace is now tilted back to t e dotted line position, shown in Figure 1 and the metal from the nozzle and some from the sprue, which .beingcomparatively large and liquid state, flows back into the furnace.

The metal does not flow back from the casting itself, as sufficient time is allowed, be

fore the above clearing of the nozzle operation, for the metal to freeze in the gates, thus holding the casting intact. The furnace is then tilted down to its'original position,

resting upon the support 18, which 1s moved into cooperative relation with the support rod 21 -by hand.

It willbe seen that the volume of flow is under complete control of the operator, through the speed at which the furnace is tilted. It is obvious that my novel furnace and mold structure is applicable to a considerable range of metals and various kinds of castings but it is particularly advantageous whetili sharp and clear cut castings are desire v Having thus described my invention, what Iclaim is:

1. In casting apparatus, a furnace, a mold, and a common means for moving the said furnace and mold relative to each other.

2. In casting apparatus, a furnace tiltable about a horizontal axis, a mold pivotally mounted adjacent said furnace, and a common means for moving the said furnace and mold relative to each other.

3. Casting apparatus comprising a furnace provided with an outlet tiltable about a horizontal axis, a mold rovided with an inlet pivotally mounted a jacent the outlet of said furnace, means for clamping the inlet of said mold against the outlet of said furnace, and means for moving the said furnace andmold relative to each other. e

4. Casting apparatus comprising a furvnace provided with an outlet tiltable about a horizontal axis, a nozzle disposed in said outlet, a mold provided with an inlet pivotally mounted adjacent the outlet of said nace, a sprue plate disposed about the inlet furnace, means for clamping the inlet of said mold against the outlet of said furnace, and means for moving said furnace and mold relative to each other.

5. Casting apparatus comprising a furnace provided with an outlet tiltable about a horizontal axis, a nozzle disposed in said outlet, a mold provided with an inlet pivotally, mounted adjacent the outlet of said furnace, means for clamping the inlet ofs'aid mold against the outlet of said. furnace, and means for simultaneously moving said furmice and mold relative to each other.-

6. Casting apparatus comprising a fur nace provided wlth an outlet tiltable about a horizontal axis, a nozzle disposed 1n sald outlet, a mold provided with an inlet lvotally mounted adjacent the outlet of sai fursignature.

of said mold and adapted to enfia e said nozzle, and means for moving sai urnace and mold-relative to each other.

7. Casting apparatus comprising a fur; nace provided with'an outlet tiltable about a horizontal axis, a nozzle disposed in said outlet, a mold rovided with an inlet pivotally mounted a j acent the outlet of said furnace, a sprue plate disposed about the inlet ofsaid mold, means carried by said sprue plate to receive the said nozzle and hold same in substantially air tight relation, and. means for moving said furnace and mold relative to each other.

8. In casting apparatus, a furnace, a mold, and means for movin the said furnace and mold together and re ative to each other.

9. In casting apparatus, a furnace tiltable' about -a horizontal axis, a mold pivotally mounted adjacent said furnace, and means for movingthe said furnace and mold together and relative to each other.

10. In casting apparatus, a furnace, a mold, and means for moving the said furnace and mold relative to each other and then moving both together.

11. In casting apparatus, ajurnace tiltable about a horizontal axis, a-mold pivotally mounted adjacent said furnace, and means for moving the saidfurnace and mold relative to each other and then moving both' together.

12. The method of casting metals which comprises pouring at one pressure for a part of the pouring operation and then at an increased pressure for the balance of the pour ing operation.

13. The method of casting metals in sand molds which comprises pouring the molten metal into a sand mold at one pressure for a part of the pouring operation and then at an 1ncreased pressure for the balance of the pourin operation.

14,15 casting apparatus comprising a tiltable furnace, a track structure attached thereto, a car resting on said track and supporting a mold in universal relation thereto,

cooperaits - In testimony whereof I hereby afiix my' HARRY P. MAUGHLIN.

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