US2471964A - Apparatus for drying and heat-treating - Google Patents

Description

May 31, 1949. A. .L KlssKALT 2,471,964

APPARATUS FOR `DRYING AND HEAT TREATING Filed May 9, 1946 2 Sheets-Sheet 1 JNVENTOR.

H77 /b/Eys.

May 31, 1949- A. J. KlssKALT 2,471,964

APPARATUS FOR DRYING AND HEAT TREATING Filed May 9, 1946 2 Sheets-Sheet 2 JN VEN TOR. f M1 JIJM? BY @WMM r f/ f Patented May 3 1, 1949 Y y A1 ff2 Thisinvention relates'to thehealtingand drying alc'dance'Withi th present invention; vconof variouskinds'of Work including metallicurdrk UVS del"r1lfg`n 'owasingle dryiilg'linit, 'the' apparatus pieces; molds, ladies, Aand the l1ike aridal ithas `lesidesfbasicallyin a col/er applicable to the contoddofparticularly with a portable sectionalzed tairler 'toth'us "f orrrianenclosed chamber. The

4 "heatiijlg anddryingapparatus 'adapted to treat 5Q'urni`t'is'eduipped withsliitableheatingmeansand the Work pieces in containers or"asks' or the -n learls-for fcircl'lletingaiiin'the chamber. The "like, "c l'lainber being closed, the"lfolul'ne' of 'air circu- The'rhetallicfuflork pieces may be itemsas lat'edisirlatively'lsmalljand is' given a temperfdies; o rfcastifngs'or sheet steel Aand other 'Workf or l"-'ature Flighenough for the s ulosta'ncetol be dried L"tems vl/l1,ich;erento bedied, such as sand molds,v '10" or heated. 'In "other Words",l` the 'gas Wthinfthe Qrplastelffmoldsmr ladlesfor molten metal v 'hi'ch fcha'rnberf is "re-circulated as"dis`tinguished from arelined with br i c k o r other zereflnict material. Athe"p as'sillg acuii'ent of air over the" Work and "Inv disclosing the invention, it is vconvenient. "to "then eih'aus'tin'g' di' ventin'gthe air. The chamber, make reference largely to molds.A 'howeverfis notsealed'sothat the'vaporized prodljhejprvailingmethod o f 4 drying sand 1no l ds,f V'15"l`lfctfs :ln'ay'scape tle'refromr'due to the pressure ;"foreiamplaior foundry purposes, isj'to placeithe dev'el'ped."" Sliitalle I-rneanssl'l'cllV as" directors 'or "1n"1 o1 1 s i n' an oven a lld heat tlflerrloldsl andnaslis. no"zzle s"re'emm'yed 'lvh'e're rthe nature of the This oven method of drying the s arldfmoldsl @vigile "rk requires same* and'tll'eseA arepre'ferably adjresulting in littleuwastendue to improper drying, "justable tojadpt the'lit't 'molds' or other Work Iei'iper'lfsile fand inconvenient. The ovensA are 20of'dife`re'nt'tlpesandshapes.

ge land requiremuch oor space. If'ano'ven is Ereferably,` the` 'indiv`idual 'unit is constructed oaded with adive'rsity of molds, some o rwhi'ch f sotha'tV itlnflaytbe detacl'l`ablycon`nected to' other are smallwand some of which are largefsomelof ylillie't'lits,"'Accodl'lgly, Where a large container .fthm remain in the ovenl longer than is nec.'ess'ary. jf is" encountered or afla'r'ge heater or cover is j Ifhis results 'in loss of time Vamil"lll-:ath B/[re-"`25"d'esred twormorefofthe units may be conover; the 'eintireimfoldand flask s tru ct ll re m f "nec'ted' togetl'ielf-'"for` 'jointi opration. lleatedall the Way through 'thus' representing 'Otheroljectsv of theA` invention will become 'ap- V 'another uneconom'ical use of heat. Tllen too, V c cn- `"l' ir=, nt "`asv 1the yfc'll'lol'll'fing detailed vdescription f is gfsiderahlefspace is reduiredfor accommodating h'cnsdeedfndonelrnr ofA structure for carrythemolds" after removalfrom the ovenfand W 1le"3Q; ing olitthe invention disclosed in tl'leaccm- KIMtheymare` cooling Metal flasks are necessa'yfor U`pa'r`1yn"g"` drawings:

h' lelli/errdrying" p` 1o; ':l s s' andfredllel'ltly delay'sior Fig. 1 is a view in the nature of a plan vie'w ecialfl'bsf are nces'sary' until the flaskA re ""Witlrpart'cutaway'to'sliowthe underlying strucrcr'ledQ VvIn asmu'ch as they ovensfare' of 'l ge ""tlire. ,onstiil'letlonndjarjn 'xeq pos'itlpn', en r^ *35 2'" aviewf-'prllylnfsideelevationend able handling and movement ofthworlis Epartly: irf" ftiofshowi'ngfne of the units. l SIIUSTSUlting in" jan excess o f labo MFig. -3 is an 'ilalgedsectinal View taken suban everpresenthagagrd of damage toI thel stantially on line 3-3 of Fig. 1 showing a strucoldlnits" handling before'and' 'after it ""'tliral fe'atn'lre.4 `b enl iliriedin the over 1 "4Q 4isank`enlazed 4flartial elevational "view Infth 'asefbf,lveryglargejmollg `@mit mme shwlnfglstructurarfeaeures.

nriotfbe'b'rjnovedf toen' overr ltil/ley? 're Fig(. 5` is'y detailed'vleWin"Section"showing a,

zzl-oir directing means.

fr 'lgl' 6i is weeen-smal vlw'lken substantially Meza-lon llnlsgjgs `or Fig. 1 illustrating ythe electrical fnrleetio`ror"ai1"e1e`ctric motor. andthed nger alwaysfeiists of ruiningfthe cast- Figa 'T' is' a'-Wtlta'iledw view-of enlarged' nature 7"ing'b'y the a'son of an'i'lbefetly driedfirlold. ""takenf'online 1%1'o`f'Fig; 1.

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tion of the unit showing the structure for detachably connecting the units together.

Fig. 12 is a sectional view illustrating a single unit applied to a ladle for use with molten metal.

Fig. 13 is a View showing a single unit applied to a container with a metallic work piece there- As above set forth the invention will be described in detail with reference to the treatment of molds.

As shown particularly in Figs. 1 and 2, each drying unit comprises a suitable body or housing I, the upper portion of which may be suitably reinforced by partitions 2 and mounted inthe upper portion thereof, preferably in a central location, is an electric motor 3. The walls of the upper portion may be provided with openings 4 so that the same may be engaged by suitable means for lifting the same by machine or hand. There is a partition wall of suitable metal 6 extending across each unit and dividing it into upper and lower portions, said wall having a passage therethrough as at l, for the shaft of the motor, as indicated. A second wall B spaced from the wall 6 has a surrounding wall structurel 9 and the space between the walls 6, 8 and 9 is preferably insulated by suitable insulating material IB. This structure forms a lower cavity II in which is mounted a suitable fan. or air propelling means I5. As shown herein this fan is of the radial flow type which takes air in its central portion and blows it out laterally although other types of fans may be used. The fan is centrally located preferably in the chamber I I and surrounding the fan are suitable heatn ing means here shown as electrical resistance elements I6 mounted upon suitable insulators Il.

The chamber Il is dened by a partition 2!) which is spaced from the wall 8 and underlies the fan and heating elements and this partition has a central opening 2l which aligns with the center part of the fan I5. The partition 2t is provided with suitable air outlet, or perhaps it would be more fitting to specify gas outlets, which are arranged to direct iiow of gas or air and which may be termed nozzles and which are shown at 22. As illustrated in Fig. 9 each nozzle may be provided with a flange 23 held by a ring 24. The nozzles being inclinedy as indicated, may be rotatably adjusted for directing the air. The nozzles are not necessary with some classes of work.

A single unit is designed to rest upon the flask 25 within which is the mold 25, and when resting in this position an interior enclosed chamber 21 is provided which communicates with the chamber II through the opening 2l and nozzles 212.

The lower edge portion of each unit is preferably reinforced as by means of an angle iron strip 3G and this strip is provided with a button which may lbe in the nature of a rivet head 3l, one adjacent each end thereof. Also, the wall of the unit adjacent its lower portion is provided with key hole slots 32. It will be noted by reference to Fig. 4 thatJ the button and key hole slots at opposite sides are reversed as to position. Therefore, when two units are to he assembled together the buttons 3l on one unit may slip into and connect with the key hole slots of the other. This is shown in Fig. 8. Also, where necessary, an outwardly extending ange such as the angle strip 33 may be applied to the lower edge of a unit as shown in Figs. 3 and Il. These reinforcing members are provided with 4 laterally extending key hole slots 35 for tting over the buttons 3|. When two or more units are secured together they may be bolted together at their upper edges for which purpose the side walls are provided with apertures 34.

It will be understood that two, three or more units may :be thus united to cover molds of different sizes. In Fig. 8, for example, four units are indicated connected together to form a square area. If the mold is long, two, three or more units may be placed in a line. Each unit is, of course, equipped with suitable means for the reception of electrical conductors for providing power for the heating element I6 and for the motor. A socket for this purpose is generally illustrated at Ml. As shown in Fig. 6, conductors 4I may -be passed through the insulation IIB and out through the partition 6 as by meansl of a bushing 42 for supplying current to the motor.

An expedient manner of use is illustrated in Figs. 9 and i0 where the work comprising the molds for example, as indicated at W, is caused to travel in the path as shown on a conveyer and the units travel in a closed path suspended from a track M, one end of which is elevated as at t5. As a work piece approaches a unit moves down to the lower portion of the track @Il and rests upon the mold throughout most of the travel and around the curve l5 and as the combined unit and work reaches about the point .'c, the unit elevates to the higher portion of the track. The molds are thus dried in a continuous fashion.

In considering the drying of a mold, it may be assumed that a single unit is rested upon the ask, after the manner shown in Fig. 2, and the motor 3 set into operation and the heating elements it energized. The fan draws air (gas) in axially through the opening ZI and discharges the saine in a heated condition radially into the outer regions of the compartment II from where the ow is directed by the nozzles 22 against the material of the mold. It is convenient to use electrical heaters as this makes the unit more easily handled although other heating means such as oil or gas burners may be used. However, the saving of time and labor in using electricity is to be taken into consideration and with this saving the use of electricity is economically feasible.

The air is thus circulated with a high velocity and is caused to penetrate into the deep pockets and recesses in the mold. To this end the nozzles may be `adjusted to properly direct the air. The mold is speedily and efciently heated and dried, this action being aided by the fact that the mold is completely covered by the drier thus retaining a maximum :amount of heat. The air (gas) volume is maintained at a mini-mum thus facilitating the attaining of high temperature, a maximum number of Iair changes with a given fan which promotes rapid heat transfer and the volatile substances in the materia-l are converted to steam vapor. The steam vapor is a good heat transfer medium and penetrates into the voids and recesses in the material and gives up heat to the deeper layers thereof thus progressively and rapidly heating up the mold. Accordingly, the mold material is dried in its innermost recesses with a. minimum of superficial or case hardening and drying. Such superficial drying and hardening may result in cracks on the face of the mold.

As the volatile substances are evaporated the same may readily escape because the combined chamber l l and 21 is tight but not sealed and the escape of the gases may readily occur at the joint where the unit rests upon the container. Thus, the process may be visualized as one wherein steam vapor is produced by the heat and which is permitted to escape from the chamber as it .is developed. Of course, the length of time it takes to dry a mold or heat other work depends upon the size of the work, the depth to which the substance is to be dried or heated and other factors. This can be regulated by those practicing the invention in a manner best calculated to produce the desired results for the work in question. This may vary also with the form and shape of the work, having in mind that some may have rather deep cavities therein and others may be relatively at in form with relatively small surface areas.

In Fig. 12 the apparatus is shown as applied to the heat treating or drying of a ladle. The ladle is shown as comprising a suitable metallic vessel 50 with a ceramic, fire clay or brick lining 5l, which is to be heat treated and dried. Inasmuch as the freshly applied ceramic may contain moisture or other volatile substances, the function of drying the same is substantially the same as that of drying molds and the above description applies. In this case, however, no nozzles for directing the air are needed because the entire surface is to be treated and there are no cavities or recesses in which the recirculating air need be directed. In addition to the drying the lining substance may be suitably heat treated for desirable time periods and temperatures.

In Fig. 13 a work piece 52 which may be a casting of metal or a forging or die or other item, is disposed in a container 53 and the heating unit I is placed on the container. In this case, there may not be any drying function but the work piece is subjected to the heat treating action for purposes as desired. Some work pieces may be normalized or tempered in this manner. In each instance, as shown in Figs. 12 and 13, the ladle or container or crucible 53 may be of circular shape and the heating units may be formed to properly t and close upon the circular upper surface thereof.

I claim:

1. An apparatus for drying a mold for founding which comprises, a housing-like body member adapted to be placed on the mold container, said body member having a, heat insulating partition for providing a substantially closed chamber, a dividing wall spaced from the partition and positioned to be next adjacent the surface of the mold, and spaced from the surface of the mold, a fan in the chamber positioned between the partition and the dividing wall for circulating the gaseous contents in the chamber, heating means adjacent the fan for heating the circulating gaseous contents, a motor located on the side of the partition opposite the heating means for operating the fan, and a plurality of directing nozzles in said dividing wall which are adjustable for the directing of the circulating gaseous contents against and into the recesses in the surfaces of the mold material.

2. An apparatus for drying foundry sand mold while in a container, comprising a housing-like body adapted to be placed upon the container over the mold, a partition extending across the housing substantially in the mid-portion thereof and including a layer of heat insulating material, a dividing wall positioned so that it is spaced from the partition and from the surface of the mold to form an upper chamber and a lower chamber, an air fan in the upper chamber, electrical heating means in the upper chamber, an electric motor above the partition for driving the fan, a plurality of adjustable air nozzles in the dividing wall so that air moved by the fan is exhausted through the nozzles and upon the mold and into recesses thereof, said body being of rectangular form, and connecting means on the body arranged so that a plurality of like bodies with similar connecting means may be detachably connected together to form a multiple unit adapted to be placed over mold containers of relatively large size.

3. An apparatus for drying foundry sand mold while in a container comprising, a housing-like body adapted to be placed upon the container over the foundry sand mold, a heat insulating partition extending across the mid portion of the housing, a dividing wall positioned so that it is spaced from the partition and from the surface of the mold to form an upper chamber and a lower chamber, said body member resting upon the container so that the lower chamber is substantially closed to prevent escape of gases from the lower chamber and is not sealed tight so that gases may escape only under pressure, a fan in the upper chamber, an electric motor above the partition for driving the fan, heating means in the upper chamber for heating the gaseous contents moved by the fan, a plurality of adjustable air nozzles in the wall through which the gaseous contents propelled by the fan are discharged into the lower chamber, said nozzles being adjustable to dire'ct the gaseous contents against and into cavities in the mold, a central opening in the dividing Wall for the ow of gaseous contents from the lower chamber back to the upper chamber, whereby gaseous contents yare .circulated and recirculated by the fan in the drying of the mold.

ADAM J. KISSKAL'I.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 455,293 Richardson June 30, 1891 2,138,624 Campbell Nov. 19, 1938 2,187,161 Kulka Jan. 16, 1940\ 2,318,393 Honerkamp May 1, 1943 2,417,673 Barnett Mar. 18, 1947 OTHER REFERENCES The Iron Age, December 26, 1946, pages (i6-68.

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