US900970A - Riser-lining for molding devices. - Google Patents

Description

E. C. WASHBURN.

BIBBB LINING FOB HOLDING DEVIOEB. Arrmunlol nu 1.511.115.1906.

900,970, l Patented 01:15.13, 1908.

. mold EDWIN Q. WAQIBURN, QF MINNEAPQLIS, MINESTA.

Rxsna-Lnmw ron nonnina Daviess.

Bpeeicaton of Letten Patent.

Patented Oct. 13, 1908.

- Appiisaon fusa 11n-oh 15, isos. saisi N. 306,117.

i To all whom it may Beit known that I, EDWIN C. WASHBURN,

a citizen ofthe United States, residing at Minnea olis, in the county of Hennepin .and State o Minnesota, have invented certain new and-useful Im rovements in Riser-Linings for Molding evices; and I do hereby declare the followi to be a full, clear, and exact description o the invention, such as .Will enable others skilled in the art to which it a pertains to make and use the same.

y invention relates particularly to apparatus for molding large and heavy castings, and is directed to the provision of anima proved.riser, whereb i certain iin roved results areV obtained, al ashereina ter set forth. l l

As is Well known, in making large .castingls the metal is usually poured into the mod through a vertical opening called a gate and another and larger opening is provided, called a riser, which permits the molten rmetal, 'after the 4mold is iilled, to'run into said riser, and to run from said riser into the to com nsate for shrinkage, as the metal cools. It is also the custom to pour considerable metal into this riser, to insure ample suppl of molten metal to fully comnsate fors rinkage of the metal in cooling.

's so-called riser must be lar e, when large castings are to be made. itherto, this riser has been formed directly in the sand and it has been necessary to form the entireI riser with large cross section land so that there has been a large surplus body of metal united `to the casting by a neck portion- 'of very large cross section. This surplus body has had to be cut off from the casting,-

. by a saw or other cuttin tool, and when the castings have been very arge and heavy and "consequently hard to handle, considerable time of several men has been required to accomplish this result. 4Ii`iirtl'ierinore, the cold and damp sand of the mold rapidly chills the metal in the'riser, and often causes the iiser,

whereit'joins the casting, to solidify too rap- `and mo d', particularl idly and to' choke up the riser, with the result that a depression or flaw is .produced in the casting,

In accordance with my invention, I pro vide a heat retaining device which will pre#4 ventra id chilling of the metal in the riser around the neck of the riseradpc'ent to t e mold, or where the body of the mold left in theriser will join 'withthe body ofthe casting, thereby per,-

metal is to mittingthe use of a comparatively small sage, adjacent to the body of the mold.

U n practice, I have found the best form of this heat retaining device to be a pot-like re- 'ceptacle construct d of baked clay, and having in itsbottom a. assage which is of much smaller cross secties than the bottom of the pot. This pot, when placed in the riser, should be located with the under surfacel of its botom alined with the adjacent surface of the mold or cavity in which the castingis "L to be formed. An ordinary flower ot' havof metal contained Within the pot will be united to the casting only by a comparatively small neck portion, Which neck portion ma be broken off by the useof a hammer or s edoe. tained b the use of a plate or disk-like body ofbak'e clay placedin the bottom of the riser, adf'acent to the body of the mold.

Bake clay is a material that will not be fused to any considerable extent by 'molten steel or other metal and, furthermore, is a poor conductor 0f heat or, otherwise stated is a good insulator of heat and, hence, will prevent the chilling or rapid cooling of the metal which runs into contact therewith. It is better, however, to .provide the riser with a complete lining such as afforded by a pot. Man other materials besides baked cla ina owever,.be used to formthe soca ed eat` retainen For instance the heat retainer, so-called, might be made of asbestos `and even if constructed of' metal or Good vresults may also be ob of wood would, to some extent, be efficient -venience, but, of course, it will be understood that the improved device may be applied at an and all places ,where molten e run into the mold.

The invention is illustrated in the accompanying drawings, wherein like characters 'view principally in section, ta en transversely through a flask and body of sand therein constituting a mold. Fig. 2 is a sectional view of the casting as it would appear when rst removed from the mold; and Fig. 3 is a sectional view illustrating a modified form of the im roved heat retainer.

The numera 1 indicates a two part flask of the 4usual or any suitable construction which, as shownl is set up on a mold board 2.

The numeral 3 lndicates the molding sand contained Within the flask and Within which is formed a mold 4 which is to give form to the-body to be cast.

The numeral 5 indicates the usual gate which opens into the cavity 4; land the numeral 6 indicates a vertical passage which leads into the mold 4, and which corresponds to the usual so-called "riser. In this riser 6 is placed the lining in the form of a clay pot 7 having in its bottom an opening 8 of considerably less cross section than the bot- 4 tom of the pot.

The numeral 9 indicates the body of the casting, the numeral 10 the lu that is cast thereon by the metal left Within the ate 5,

l and the numeral 11 the lug or body o metal central cast integrally with the body 9, by the metal left Within the pot 7. The lu 11 it will be seen, is connected to the bo y of the casting by a contracted neck ortlo'n 12, so that it may be easily broken o from the casting. The casting shbwn is in the form `of an ingot, but, of course, in practice it`may be of any form so far as my invention is concerned.

In Fig. 3, the numeral 13 indicates the disk.

or plate, preferably of baked clay, having a passage 14, the said disk or vplate .being laced at the bottom of the riser 6 with its un r surface adjacent to or alined with the upper surface of the casting 9.

My ek eriments up to date go to show that by t e use of the simple device above described, castings'may be roduced Which will not have flaws due to t e cause above stated and furthermore, that a very material saving' of labor is effected by making it ossible to break rather than saw the lugp 11 from the body of the casting.

It will' be noted that the only difference betweenthe 'forms of the device shown in Figs. 1 and 3, is that the perforated disk like bottom or body shown in Fi l, is provided with avertlcal lange, W ich fiange able portion o the upper Wall ofthe mold, A.

a thin partition between the top and formin c? and the bottom of the riser, the

of themol said disk-like bod having a central perforation through Whic the molten metal may be poured into the mold, substantially as de'- scribed.

In testimony whereof I afix my signature in presence of two witnesses.

EDWIN oWisHBURN. Witnesses:

, MALIE Hom.,

F. D. MERCHANT.

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