US1074485A - Drier-kiln. - Google Patents

Description

P. W. BALLARD.

DRIER KILN.

JQPPLIGATION FILED DB0. a, 1911.

www Essa@ MWA-Wilmn? IBY ll'NlTED STATES .rnrnrrr ortica.

FREDERICK W. BALLARD, OI'F CLEVELAND HEIGHTS, OHIO, ASSIGNOR T0 THE SHERWIN- WILLIAMS COMPANY, OF CLEVELAND, Gil-H0, A CORPORATION F OHI. l

DRIER-EKILN.

Specication of Letters Patent.

Patented Sept. 30, 1913.

.application nea December a, 1911. .serial no. 664,546.

T0 all whom t may concern.'

Be it known that I, FREDERICK W. BAL- LAR, a citizen of th'e United States, and a resident of Cleveland Heights, county of herein explained andthe best mode in which I have'contem-plated applying that principle, so as to distinguish it from other inventions. In the manufacture of furniture and more particularly `of einer articles of furniture, such as pianos and the like, avery considerable delay has always been involved in the linishing o r varnishin-g process;- for a number of coats of one kind or another of oil, varnish or paint, require to be applied, after application of each of which suilicient time must be allowed for such coat to dry before the next is puton. The `present improved drier kiln is intended to provide means whereby this drying operationmay Ibe much facilitated, thus correspondingly shortening the process of manufacture of furniture and articles of the kind referred to, although insuring an equally good, or even better finish than Where\ the ordinary protracted drying in the open air is relied on.

To the accomplishment of the foregoing and related ends, said invention, then consists of the means hereinafter fully. described and particularly pointed out in the claims. The annexed drawing and the `following description set forth ih detail certain mechanism embodying my invention, such disclosed means constituting, however, but one of the various mechanical forms in which the principle of the invention may be used. In said annexed drawi s:.-Figure 1 is partly an end elevation an partly a transverse vertical section of a kiln embodying my present improvement; While Fig. 2 is a central vert-ical 'section taken at right angles to Fig. 1f

In the simple structural embodiment of the invention illustrated in the foregoing figures, the chamber 1, into which the articles to be dried are desi ed to be placed, is of general rectangular orm and is furthermore arranged with a floor 2 raised above the earth or other supporting surface, although. this is not essential. This chamber .may be entered through a door 3, but when` the apparatus is in operation, it is closed as `hereinafter specified. Laterally of this `chamber are vertically extending chambers or passages 4, one on each side, that are vopen at their lower ends and communicate tvith said malin chamber 1near the floor line t-hrough openmgs 5, as also with the exterior through other openings 6, these openings G being preferably closed by sheets 7 of cheese' cloth or other filtering medium stretched there-across. These lateral passages-4 at `their` upper ends communicate with a chamber 8 that 'is located 4directly above the central lcham-ber 1 and separated vtherefrom by a. perforated, horizontally extending partition 9,-as shown. Such communication may be had either directly by passages 10 or through passages 11 that'lead over receptacles in the form ofy shallow pans 12 con taining water. Strips 13 of cloth or wicking depend across these latter passages into the Water in the pans, so that when air passes therethrough it may become rela-tively humid or saturated With moisture.

Disposed in the lower portions of the re'- spective lateral chambers or passages 4 are suitable heating means, preferably in the' form of coils 14, through which steam or .other suitable heating medium may be circulated. Gates or doors 15 arearranged at the bottom of each lateral passage so as to close the sameeither to the exterior, or to the interior of the kiln, as desired or to assume its desired intermediate position. Each set of these gates is carried by Va common shaft ,16 provided with a pointer-17 at one end, so that the exact position of the gates may be indicated on a suitable indicator without the end Walls of the kiln. Other gates, or valves 18, on sim-ilarshafts 19, at the upper ends of the passages are adaptedto directv the current of air either through the passages 11 over the pans of Water, or through the' open passages 10, into the air chamber 8 directly above the main chamber of the kiln. The sition of these upper gates is likewise indicated by means of ointers 20. The Water level in the pans, wh1ch are connected by a pipe 21, is maintained constant by a float valve 22 located in inl auxiliary supply tank 23 outside of the Having thus described with sufficient detail the construction of my improved drier kiln,its mode of operation may be briefly set forth. Assuming the article to be dried admit-ted to the heating coils 14, as a result of which the air in said passages is heated and so caused to rise. Upon reaching the top or the upper ends of the passages, thls Warm, ascending current of air is normally passed across the pans or receptacles 1Q which contain water, as previously stated. The eifect of thus passing Warm, dry air over the surface of this Water, or through between the strips 13, is to evaporate some of the Water, whereby heat is absorbed, becoming latent. The current of air is accordingly not only humidified but also cooled to a degree which causes it to descend downwardly into the main chamber, the downward flow of air being evenlydistributed by reason of the interposed perforated partition 9. Then the proper temperature has been arrived at, this being determined in general by the amount of steam admitted to the heating coils, the gates 15 may be opened more or less, as shown in Figs. 1 and 2, so as to permit a finer adjustment of the temperature and at the sam'e time to add a fresh supply of air to that contained Within the kiln. This .is desirable, because the operation involved is not strictly a drying one, as the term is ordinarily used in connection with the drying of lumber, but rather consists in the oxidation of the varnish or other coating applied to the article. Accordingly, the air used in drying should contain its normal quota of oxygen. The presence of a certain amount of moisture in the air used in thus drying the varnish, or paint` on the articlel being dried, is also recognized as essential, for if the air be'too dry it has been found that the drying operation does not proceed satisfactorily. Such drying operation, it will be understood does not involve the extraction of moisture, that is Water,- at all, but relates Wholly to the hardening or oxidizing action of the air. It is also desirable that the coat of varnish be thus oxidized from the bottom up, whereas, if the air be too dry, a thin ilm on the surface is initially hardened and the coat is brittle and apt to be checked. Accordingly I prefer t-o maintain the content of moisture in the air, that passes over the article being dried, rather high, my experiments indicating that best results are obtained where the air is practically saturated.

The direction arrows on Fig. 1 indicate the general circulation of the air occurring Where the gates are arranged in the manner there shown; that is, there is a combination of outside 'and inside currents of air. Where the gate is in the position 15 (shown in dotted outline), the clrculation is all inside; While, conversely, in the position 15 an entirely fresh current of air is drawn in through openings G and discharged through openings 5.

By the foregoing arrangement of chambers and disposition of the heating coils and humidii'ying means, it will be seen that such coils and humidifying means cooperate to produce the necessary circulation of air; that is, the column of heated air ascending in the outer chambers is sufficiently cooled, incidentally to its being moistened to the desired degree, to cause it to descend through the drying chamber proper. Thus there is no energy Wasted, but the heating coils and humidifying or moistening means coperate in maintaining the desired circulation, without the use of any mechanical current-producing means or the condensation of moisture from the air (Where it should remain) by means of cooling'coils. From the drying chamber the air may pass into the lateral chambers there to be again heated and so caused to flow in the same path as before. A careful and exact regulation, both of the temperature and of the amount of moisture in the circulating body of air, is rendered possible by the adjustable gates or valves previouslyadescribed, so that by the use of suitable indicators, such as a thermometer and hygrometer, the drying operation may be exactly and scientifically controlled.

Other modes of applying the principle of my invention may be employed instead of the one explained change beingr made as regards the mechanism herein disclosed, provided the means stated by any of the following claims or the equivalent of such stated means be employed.

I therefore particularly point out and distinctly claim as my invention 1. In a kiln of the class described, the combination with a main drying chamber adapted to receive the article to be dried; of an auxiliary chamber communicating with the upper portion of said main chamber: means adapted to heat the air in said auxiliary chamber, whereby an ascending current of air is created therein; and other means above said main chamber adapted to humidify such current of air by the evaporation of a liquid, whereby the air is cooled and caused to descend into said main chamber independent of any agency in the latter.

2. ln a kiln of the class described, the combination with a main drying chamber; of an auxiliary chambercommunicating with the upper portion of said -main chamber; heating coils located in the lower portion of said auxiliary chamber, whereby an ascending current of air is created therein; and air-humidifying means located above said main chamber and adapted to cool such current of air and thereby cause it toydescend into said main chamber independent of any agency in the latter.

' thereby cause it to descend into saidmain 3. In a kiln of the class described, the,

combination with a main drying chamber; of an auxiliary chamber; two passages connecting said auxiliary chamber with the upper portion of said main chamber; means for optionally closing either of said. passages; air-humidifying means located in one of said passages; and air-heating means located in said auxiliary chamber,

4. In a kiln of the class described, the combination' with a main drying chamber; of an auxiliary chamber connected at' its lower portion with the lower portion of said main chamber and with the exterior; means for closing one connection or the other, as desired, said auxiliary chamber being also connected with the upper portion of said main chamber; means adapted to heat the air in said auxiliarychamber, whereby an ascending current of air is created therein; and other means above said main chamber adapted to cool such'current of air and chamber. y

5 In a kiln of the class described, the combination with a main drying chamber; of an auxiliary chamber connected at its lower portion with the lower portion of said mainchamber and with the exterior; means for closing one connection or the other, as desired, said auxiliary chamber being also connected with the upper portion .of said main chamber; means adapted to heat the air in said auxiliary chamber, whereby. an ascending current of air is created therein; and other means above said main chamber adapted to humidity such current of air by the evaporation of a liquid, whereby the air is cooled and caused to descend into said main chamber.

Y 6. In a liln of the class described, the

combination with a main drying chamber; of an auxlhary chamber connected at 1ts .lower portion with the lower portion .of .said main chamber and with the ex terior; means for closing one connection or the other, "as desired, said auxiliary chamber being connected with the upper portion of said main chamber by two 'separate passages; means adapted to close ,elther of said passages, as desired; airhumidifying means located in one of said passages; andan-heating means located in said auxiliary chamber.

'7. In a kiln of the class described, the combination .with a main drying chamber; of an auxiliary chamber communicating with the lower portion of said main chamberandwith the exterior; means adapted to control such communication, said auxiliary chamber beingconnected with the upper portion of said main chamber by two separate passages; means adapted to close either of said passages, as desired; air-hu midi-.tying means located in one of said passages; and air-heating means located 1n said auxiliary chamber.'

Signed by FREDERICK WBALLARD.

` Attested' MYRTLE K. SoHUoH,

JNO. F. OBERLIN.

me this 6th dayiof December,

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