USRE4991E - Improvement in driers - Google Patents

Description

B1B. HAWLEY. Improvement i n.Drie r s. No. 4,991. ed Ju|y1s',1a12.

0 O O O Q G O O G G U 0 O O O 6,! O G ,p Q (git a:

O O O Q Q Q 9 O Q Q. V127, erred". Fzverzia UNITED STATES PATENT OFFICE.

BENJAMIN R. HAWLEY, OF NORMAL, ILLINOIS.

IMPROVEMENT IN DRI ERS.

Specification forming part of Letters Patent No. 84,117, dated November 17, 1868; reissue No. 4,991, dated July 16, 1872.

Figure 1 of the accompanying drawing is asectional elevation,bisecting the said house or kiln longitudinally. Fig. 2 is a horizontal section taken on the line as y of Fig. 1, and Fig. 3 is another horizontal section taken on the line as y of Fig. 1.

A represents the outer walls of this house or kiln, which may be constructed of any suitable or approved material adapted for the requirements of drying-kilns for using air heated to two or three hundred degrees of heat ormore. In the bottom part of the house or drying-chamber will preferably be the fire-box of the heater B, which will be inclosed by the "ertical walls of the hot-air chamber B, so as to leave an air-passage, b, surrounding the said fire-box on all sides except that occupied by the fuel-door. From the top part of. the firebox rise the suioke-tubes G, which are also inelosed in the hot-air chamber B, and which convey the smoke from the furnace to the smoke-pipe C, and thence to the chimney D. Several small pipes O are used,in order to have more radiating-surface than one large one would give. The hot'air chamber or well B extends nearly to the top of the house or kiln, or at least to the height of the top shelf or floor. Surrounding the hot-air chamber, or arranged by the side of it, are the dryingchambers A, which are fitted with shelves 11.

or other equivalent devices, for suspending the articles to be-dried. The cold air which is fed into this kiln first enters the chamber or passage b at the bottom of the house, which is row, the cold air comes in direct and intimate contact with the heated plates of the fire-box and the tubes 0, and is quickly heated thereby. From the top end of the chamber B the heated air will pass over into the chamber A in the direction of the arrows and down through the said chambers to the bottom thereof, where it passes into and escapes up through the draught-chimneys D, thus securing a more even and uniform application of the heat than can be had where the air escapes from the top,

because in descending from the point where it is discharged into the drying-chamber it first spreads evenly over the whole area, and it tends, naturally, to descend as it becomes charged and cooled with the moisture expelled from the substances under treatment, which is heavier than the heated air. Ducts a should be provided at-the bottoms of the chambers A, for affording free passages for the heated air from the corners of said chambers to the said chimneys.

By means of the foregoing arrangements a very large volume of air may be heated. and applied to drying purposes, and the heat will be economized, first, by the mode of heating the air in b and B, and, secondly, by having the air pass downward in the manner described.

It will be perceived that no artificial pressure is employed in this form of drier to impel the downward current of heated air, the action of the draught-chimneys D.being amply sufiicient to'withdraw the saturated and cooled air from the bottom of the chamber, the place of which is constantly supplied by the gravitatin g current of heated air as it condenses and accumulates. moisture.

I claim as my invention 1. An air-heater and a drying-chamber, combined and arranged in such manner that the air not combined with the produets.of-combustion from the heater is delivered into the upper part of the chamber, caused todescend along the articles to be dried as it absorbs the moisture thereof and becomes cooled, and is exhausted from the bottom of the chamber by the natural action of a vertical draughtchimney, substantially as specified.

2. The dry-house or kiln A, when provided with a furnace having an air-inlet, b, snrroundair chamber b and B, arranged and combined ing the fire-box; also a heating-chamber, B, with the drying-chamber substantially. as

which is arranged to conduct the heated air specified. Y I to the top of the building; and alsothe chim- B. R. HAWLEY. neys D, arranged to take the cold and vitiated air from the bottom of the drying-chamber, Witnesses: substantially as specified. JOHN H. Scum,

3. The fire-box B, smoke-tubes O, and hot- WM. H. BROWN.

Images