US769103A - Dry-kiln. - Google Patents

Description

y A No. 769,103. 1 PATENTBD AUG. 30,-1904.

LAFAYETTE MOORE..

DRY `KILN.

PATENTED AUG. 30, 1904.

LA FAYETTB MOORE.

DRY KILN.

APPLICATION FILED IEB. 2, 1904.

3 SHEETS-SHEET 3.

N0 MODEL.

witwassen wm IST Patented August 3o, 1904.

PATENT OFFICE.

LAFAYETTE MOORE, OF OORDELE, GEORGIA.

DRY-KILN.

SPECIFICATION forming part of Letters Patent No. 769,103',r dated August 30, 1904.

Application led February 2, 1904. Serial No. 191,716. (No model.)

T a/Z whom t may concern:

.Be it known that I, LA FAYETTE MOORE, a

Acitizen' of the United States, residing at Oor@ 4dele,'in the county of Dooly and State of 'Georgien haveinvented a new and useful Imadopted for concentrating the heat and va-` rious attempts have been made for maintain- 1 sides.

ing an even temperature throughout the kiln.

For instance, it has been proposed to' take in air at the bottom and circulate it throughout the interior of the kiln, the entire upper portion of which was air-tight, and then recirculatethe air from the top of the kiln by conducting it downward through iiues at the It was also proposed to absorb the moisture by providing a layer of absorbentl materiaL such as sand, at the base in a kiln whose top .was air-tight and which had airflues at the base; but my present invention contemplates a kiln-chamber which is practically air-tight at the base and sides and sealed at the top a short distance above the lumber and provided immediately below the ceiling 30.

with Ventilating-ducts, the outlets of which are controlled by pop-valves which are automatically opened and closed by the pressure i of the confined gases within, and in my preslent invention the .only air admitted from below is supplied through the cracks or crevices at the doors or between the doors and door-jambe.

Another object is to provide Lmeans for sweating or steaming hardwoods preparatory to their entrance to the kiln and at the same time at a convenient place in close proximity thereto, so that the tr uck from the steamer after With the foregoing objects in view my pres- 'ent invention consists in a dry-kiln vand scalding-box arranged in close proximity to each other, so that the lumber can be transferred from one to the other with facility and so that hard lumber can be undergoing a steaming process independently of the kiln-drying and preparatory thereto where the lumber being treated is of a class which requires such preliminary treatment. i 4

In connection with the foregoingv my present invention also consistsl in means for heat-A ing and Ventilating the kiln in such a manner as to hold the moisture expelled from the green and wet lumber in suspension throughout the interior of the kiln, so that all nortions of the contents are treated at the same vtime with the greatest economy in the expenditure of heat by applying and utilizing the maximum amount of heat at the entrance of the kiln, where the lumber to be treated is the greenest and the wettest.

It still further consists in a system of heating and Ventilating which precludes the possibility of explosion or combustion by theignition of gases, all of which I accomplish by maintaining a practically even tempera- .ture and uniform moisture throughout the entire interior of the kiln, just so much fresh air being supplied as is necessary through the door-cracks, therefore in very limited quantity, and .just so much of the heated air and kiln as the uniform internal pressure causes to automatically escape.

My invention further consists' in certain va detail, and Fig. 4 is a view of a ventilator v used where several kilns are employed.

A represents vthe'scalding-box, and B isrthe kiln, the two being located in comparatively moisture being discharged at the top of the close proximity to each other-say about two feet apart-to afford suflicient space for a person to pass between them. The scaldingbox and kiln are located on a suitable platform, and the tracks 1, 2, and 3 continue right through the two on a gradual incline in order to facilitate the movement of the trucks 4 4 from one to the other and throughout the lengths of the two buildings. These buildings are erected upon a suitable foundation or framework of horizontal and upright timbers 5 and 6, respectively, which affords a suitable space below the track-line for the heating apparatus. The usual doors 8 8 are provided for the scalding-box and kiln, weights 9 9 being provided to counterbalance them and to facilitate in opening and closing them. The purpose of the scalding-box is for steaming hard lumber preparatory to the dry-kiln process, and by the use of this scalding-box the hard lumber is brought to a condition somewhat similar to pine and other soft lumber in readiness to be subjected to the same kiln-drying process for practically the same length of time that the softer lumber requires, say from forty-eight to seventy-two hours. This scalding-box may be heated in any convenient manner, and an approved plan for accomplishing it is to run a branch pipe 10 from the main 11, to which it is coupled bythe T-coupling 12. This branch pipe 10 is provided with a discharge-nozzle 13 and a valve 14 for controlling the discharge of steam into the box. Independent pipes could of course extend from the boiler to the box and kiln. From the opposite end of the T-coupling 12 a pipe 15 leads into the base of the kiln B to a header 16, through which the steam is distributed into the battery.

The material being dried is subjected to the greatest heat upon its entrance into the kiln, the heat being gradually reduced as the lumber proceeds toward the discharge end of the kiln, the reason being that the lumber is green as it enters the kiln, and were it subjected to the same degree of heat throughout its progress through the kiln the lumber would be ruined owing to a too rapid drying. On the other hand, if the heat was reduced to that degree radiated at the discharge end of the kiln the process of drying would occupy a great deal longer and the product would be inferior in grade.

Immediately below the ceiling the boxes 29 29 are provided. lThese are very much like those employed in my Patent No. 635,57 2 of October 24, 1899, except that they do not extend entirely across from side to side, with slots in the bottom, as I find for my present purposes it is quite as effectual to make them shorter and Wide open at their inner ends instead of being slotted at their lower sides. Flap-valves 30 30 are provided at their outer ends, which valves are automatically controlled by the steam-pressure from within.

It is hardly necessary to repeat in this ap# plication what I have so fully stated in the patent above referred to about the heating up to boiling-point and the creation of steam by heating the sap of the wood to a point of vaporization. I will merely state in conclusion that my system of ventilation and applying heat is such that the heat is utilized economically. It is concentrated, and the heat and steam generated from the lumber being dried are evenly disseminated throughout the entire interior of the kiln, the moisture being held in a state of suspension in order to protect the outside surface of stock and not being precipitated, so that the lumber is uniformly subjected throughout its entire surface to an even heat and moisture, thus preventinghollow-horn, checking, and case-hardening.

It is evident that slight changes might be resorted to in the form and arrangement of the several parts described without departing from the spirit and scope of my invention, and hence I do not wish to limit myself to the exact construction herein set forth. For instance, a number of these kilns and scaldingboxes might be arranged side by side, according to the size of the plant to be constructed and the capacity for work required.

Having fully described my invention, what I claim as new, and desire to secure by Letters Patent. is

1. The combination with a kiln, of a series of trunk-ventilators extending from the outside part way across the interior of the kiln' and automatic Hap-valves carried by the ventilators, the excess pressure from within the kiln operating to open the valves.

2. The combination with a kiln, of a series of tubes projecting from without the kiln part way across the interior of the kiln, the inner ends of the tubes being open and Hap-valves hinged to the outer ends of the tubes, the valves normally closing the tubes against the entrance of air to the interior of the kiln and being automatically opened by the excess pressure within the kiln to release the same.

3. The combination with a kiln, of ventilators located in the upper portion thereof and extending part way across the kiln from the4 outside and doors normally closing the outer ends of the ventilators, the doors automatically opened by an excess pressure within the kiln.

In testimony whereof I have signed this specification in the presence of two subscribing Witnesses. f

LA FAYE'ITE MOORE. Witnesses:

C. A. TowNsnND, J. GrJoNEs.

IOO

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