US1749448A - Drying sand molds - Google Patents

Description

Mafch 4, 1930.

R.SCULTHQRPE DRYING 5 AND MOLD S Filed Nov. 17. 1928 2 Sheets-Sheet l March 4, 1930. R. scuLTHoRPE DRYING SAND MOLDS Filed Nov. 17. 1928 2 Sheets-Sheet 2 JMENTZR M rily in drying molds they are subJ'eCted to the Patented Mar. 4, I 1930 1 u NIT-ED I PATENT oil-Fist:

nAY sc LTHonPE, or snenrsv nnn, PENNSYLVANIA, Assion'on 'T'o srrnnieneo rnnn MOLD COMPANY, on sHARPsvI jIJE,,TPENNSYLVAN A, A 'ooItP nAr I'oN or "PENN- SYLVANIA Application 'filed. November 17, 1928.

I This invention relates to the drying of sand of sand molds for casting metal. 'Itcontemplates an apparatus formore effectively utilizing the drying medium used in drying the 1 molds than has heretofore been possible, and a method-of drying such molds. Sand molds for use in metal casting-are first prepared by packing sand in a suitable flask or, container using a suitable pattern or smoothing device, and then subjecting the packed sand to the action-of a drying medium for the purpose of driving out the cont'ained moisture and preparing the sand-f walls for the: reception ofthe molten metal. Ordinaaction of hot gases, which may be the produc'tsofcombustion from a furnace. The dryin'g gases are conducted into the presence of moldandare allowed to flow in proximity thereto, heating the sand walls and'abstracting the moisture therefrom.

loss in {Usually the molds are placed either in a drying oven or upon a rack, provisionbeing made below themolds for theadmission of drying gases. 'Ordinarily the respective molds are placedsubstantially above open- "ings in the bottom, of the rack, the drying gases emerging from such openings and passing in proximity'to the molds.

When the molds to be dried are of small size and so positioned that the drying -gases emerging from the conduit'conveyin-g them into the presence of the mold must necessarily impinge thereagainst, thedrying is eflectivel'y accomplished. However, wheirthe molds'are oflarge size or of such shapethat oneormore of the sand surfaces cannotbe placeddir'e'ctly in the ath of the drying gases, a marked I rying elficiency results. Gaseous bodies have a tendency to stratify' andflow ,insegregated masses, particularly in'cas'es Where the temperature of a flowing gaseous body is materially different from the temperature of the surrounding atmosphere. A

" body of drying gases emerging from the conduit conveying such gases into'the presence of jsegre'gate and to flow in a direct path in the ,directiono'f least resistance. Ordinarily-this nnyino {SAND MOLDS Serial No. 320,186.

direction is upwardly because the temperature of the surrounding, atmosphere is mate.- riallylower than that of the'dryin g gases.

"In thecase of 'an'y but-thesinallest and simplest molds therdryin-g gases may impinge against a small portionof the sand suriace thereof, but willrusuallyrise upwardly and tend to stay away from the sand surface. For example,-this. condition is quite marked in the case of large sized sand surfaced. ingot 'molds. Such =moldsare normally placed over dryinggas outlets so that :the gases emerge in the interiors thereof. A natural chimney effeet is createdv in such .a 'mold and the gases take the path of 'least resistance, namely, straight upwardly. throughthe centerh-o f the moldwithout' comingiinto intimate contact with the sand walls. On'ly a'small proportion of the available 'dryingelficiency is utilized.

I provide an apparatus and. methodfor drying sand inoldsiadaptedto obviate the disadvantages 'above noted "and to more 'efli- "cien'tlyan'd effectively dry thesand than has heretofore been possible: I provide a source of gases, a conduitfor conducting the gases into the presence ofaino-l dwall, and-means surface and having supporting means spacing the deflecting surface from i the means upon which the deflecting means is supported. I still further provide a method of dr ing sand mold'walls comprising introducing dry- ,in-g gases into the presence of a wall 'and dimeeting the path of the gases therealong.

Other objects and advantages will become apparent as the following description of a presentpr'eferred embodiment of the invention proceeds.

' In the, accompanying drawings, 1 have shown a present preferred embodiment of the inventionwhe'rel'n Fi'gu're 1 is a cross sectional view through a mold drying apparatus having a mold in place thereon,

escape and upward flow of the drying gases contained therein. The top surface of the flue-serves as a support or base upon which are placed flasks 5 having sand molding surfaces 6. The sand is first introduced and suitably packed or rammed withinthe flask,

after which the flask is placed on the rackor flue for drying. The mold is provided with a down pouring gate 7 and an-in pouring gate 8. r

Resting upon the rack and preferably disposed directly above an opening or conduit 4 is a deflecting device designated generally' by reference numeral 9.1 This device comprises a lateral deflecting'surface 101 and a plurality of legs'llspacing the surface lO-from the top of the rack. The device is further provided with a laterally extending conduit 12, one extremity of which opens bepreferneath .the deflecting surface 10 and ably substantially above the conduit 4. The outward extremity ofthe conduit 12 extends toward and into proximity with the 1117130111- ing gate 8. The inner extremity of the conduit 12 is beveled, as shown in Fig.1, thus to provide for the reception of as'large'a quantityof drying gases as is practicable.

The drying gases rising upwardly through theopening '4: in;.the rack have a natural tendency, as above explained, to stratify and rise straight upwardly without coming into intimate contact with the sand walls of themold by reason of the interposition of v the deflecting device 9.' However, the stream of drying gases is deflected or interrupted and caused to segregate and flow laterally in all directions. Due to thefsubstantial velocity of the gases, this lateral flow-causes them to impinge with considerable force against the sand walls, and as their natural tendency is thereafter to rise straight-upwardly, they willrise in substantially intimate contact with the walls, thereby most eflectivelydrying them. I f

Heretofore great difficulty has been :experienced in drying the pouring gatesinas -much as the inner extremity ofthe in gate is near the bottom of the mold and the gases have an opportunity to move past suchgate before moving laterally to a sufficient-extent I to enter it. In many instances in an effort to completely dry the gates to enable the metal to be poured, the sand walls have been badly mold wall. v I V 2. The combination of a source'of gases for drylng sand mold walls, means for contion of the burned, necessitating the putting aside of the mold without being used. This disadvantage is overcome'by the provision of the device 9 having a laterally extending conduit 12 which directs a substantial volume of the drying gases toward and into proximity with the pouring gate. The gases which do not pass through the conduit 12are mushroomed 'or laterally 'deflectedin alldi'rections and pass upwardly along the inner sand wall 6. Thus a most efl'ective and quick drying of the mold is accomplished.

v.VVhen molds-without pouring gates are being dried, the conduit 12 may be omitted from the deflecting device 9, if desired, or in case a. portion of the sand surface is of greater thickness than another portion, the-conduit 12 maybe utilized to convey a substantial volume of dry gases into proximity with the thicker portion. The deflecting device is adjustable to cause a greaterfproportion of the gases to be directed as may be desired, and is very easily removed by merely lifting it with-a hook orother suitabletool.

l Vhile I have shown and described a present preferred embodiment ofthe invention, I wish itdistinctly understood that the same is not limitedthereto, but may be otherwise embodied and practiced within the scope of the following claims. I claim:

1. The combination of a source of gases for drying sand mold walls, means for conducting the gases into the presence of amold introduced into drying relationship with the ducting the gases into the presence of a'mold wall, and-an adjustable and removable baffoo fle device for deflecting the gases asthey are ios wall, and means for directing the gases toward the mold wall, such means .havingprovision for directing at least a portion of the.

gasfis toward a localized portionof the mold The combination of a sourceof gases for-drying sand mold walls, means forconducting the gases into thev presence of a mold wall, and meansfor directing the'gases to? ward the mold wall, such means having a conduitrfor directing at least a portion of the gaslas toward a localizedportion ofthe mold 4. The combination of a source of gases for drying sand mold walls, means for conducting the gases into the presenceof a mold wall, having a pouring gate therein, and

meansfor positively directing at least a por- V gases toward'and into proximity with the gate. V

5.. The combination :of a source of gases fordrying sand mold walls, means for conducting the gases into the presence of a mold wall having a pouring gate therein, and

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means for directing the gases toward the mold wall, such means having provision for directing at least a localized portion of the gases directly toward the gate.

6. The combination of a source of gases, for drying sand mold Walls, supporting means for a mold having a conduit therein for conducting the gases into the presence of a mold wall, and a removable deflector resting on the supporting means in the path of the gases.

7 In apparatus for drying sand mold walls, a deflecting means having a deflecting surface and having a conduit extending generally laterally from such surface.

8. In apparatus for drying sand mold walls a deflecting means having a deflecting surface, legs spacing the deflecting surface from the means upon which the deflecting means is supported, and a conduit extending out- Wardly therefrom.

9. In apparatus for drying sand molds, a

Y deflecting means adapted to be interposed in the path of drying gases, such means having a surface adapted to deflect the gases sub stantially laterally and having means for con ducting a portion of the gases in a desired 7 localized direction.

10. In a method of drying a sand mold having a pouring gate, the steps comprising introducing drying gases into the presence of the mold, deflecting the gases toward the mold, and conducting a quantity of gases toward and into proximity with the gate.

In testimony whereof I have hereunto set w my hand. I

RAY SOULTHORPE.

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