USRE327E - Improvement in air-heating stoves - Google Patents

Description

J. M. THATCHER. .y

Hot Air Furnace.

Reissued Sept. 11, 1855.

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`Jersey Gity, county of Bergen, and State of UNITED gSTATES PATENT OFFICE.

J. M. THATGHER, OF JERSEY CITY, NEW JERSEY.

IMPROVEMENT IN AIR-HEATING STOVES.l

Specification forming part of Letters Patent No. 8,832, dated March 23, 1852; Reissue No. 327. dated September 11, 1855.

was to avoid the diiiculties vabove enumerated; and to these ends my said invention consists in giving to the plate or plates which form the bottom of the iue space or spaces for To all whom, t may concern:

Be it known that I, J. M. THATGHER, of

New Jersey, have invented certain new and and Furnaces and I do hereby declare that the following is a full, clear, and exact description of the saine, reference being hadv to the accompanying' drawings, forming part 0f this speciiication, in which- Figure lis a vertical section of one of my improved stoves, taken through the center. Fig. 2 is a horizontal section ofthe same, taken in the line x m shown iu Fig. l. Fig. 3 is a plan or top view of the same having `the capremoved. Figs. 4 and 5. are detached views of parts of the interior. Fig. 6 is a horizontal section taken through the line y g/ shown in Fig. l.

Similar letters ot' reference indicate corresponding parts in each of the several figures.

In air-heating stoves and furnaces for warming' apartments and buildings, and for other purposes, it is highly important to have the products of combustion from the lire-chamber inside pass among and around the air tubes or passages to increase the extent 'of heatingsurface, and to effect this economically and advantageously it has been deemed importhrough the spaces forming the iiues, and circulate through them all before reaching the chimney, and also to allow the air to pass diber, so that all particles of ashes, soot, or other solid matter falling upon such plate or plates may be returned by gravity into the lire-ch amber, and thus keep. the flues clear for draft, and also the surface of the plate or plates for the transmission of heat to the air-passages; and my said invention also consists in the employment of a series of hollow cylinders or tubes, of anysuitableform, arranged one within'another above the fire-box and around the chimney, with a space all round between every two of them, certain of such spaces being connected at the top and bottom to form iiues leading from the fire to the chimney, and the intermediate spaces between the irst-named spaces forming air-passages through which, and through smaller tubes passing through the iiues, the air passes-to be heated. The connections between the several spaces are formed outward, and then, if required, inward to the exit-pipe, while the air is carried in a. general direction upward 5 but to effect this in a practical wayhas been attended with serious difliculties. The plates or rings forming the fluespaces for the passage of the products of combustion outward or inward have prior to my invention been made dat and horizontal, or nearly so, and as in all stoves and furnaces having a good draft great quantities of ashes and other solid particles of matter are carried up from the fire-chamber by the force of the current, these, together with the soot, lodge upon these plates, and in a short time obstruct the draft, and by reason of their bad conducting properties prevent the heating of the plates, and, as a necessary consequence, the air coming in contact with their opposite surfaces.

The leading object of my said invention the greatest How through those parts where the heat is most intense.

To enable others skilled in the art to make and use my invention, I will proceed to describe fully its construction and operation.

A is the outer casing of the stove, which consists-of a cylinder of sheet metal.r It is set upon a cast-iron base-plate, B, below which is thev ash-pit C.

D is the tire-box, which rests upon the plate B.

E is the grate.

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the said space O being covered and closed by a ring of metal, so as to close all outlets except through the said tubes o o.

V is the cover of the stove, which fits to the outer casing, A, or to the plate U. It is of dome shape and raised sufciently above the plate U to form a receiving and distributing chamber, Y, for the heated air, the chimney S passing through it. It is provided with openings q q, through which the air is distributed.

W is the fire-door, through which fuel is introduced to the lire-box.

1', Fig. 1, represents one of aseries of openingsl in the plate B, around the foot of the fire-box, through which the air is admitted to be heated.

It will be understood by reference to Fig. 1 that when the damperJ is closed the draftfrom the fire plays between the tubes b b, ascends the annular flue L, and then passes between the tubes p p, descends the annular ilue It, and, after passing between the tubes i i, ascends the chimney S, its course throughout being indicated by arrows in the flues.

The air to be heated is supplied through the openings r in the base-plate, rising up to the inverted dome F, which spreads it, and part of it ascends the outer passage, II, and passes through the openings m m to the chamber Y, while the other ascends the tubes b b ff to the space between the inverted domes I and M, where it is again divided, part of it passing up the passage 0, and through the tubes o o to the chamber Y, and the remainder through the tubes it' and passage T to the said chamber, from which it passes oft' to the F is an inverted circular dome of cast-iron, having an opening through its center, surrounded by a rim, e, which fits to the top o f the fire-box, andhaAvin g also another rim, a., which stands up from its outer edge. It has a number of small tubes, b b, standing up from it, ranging in a circle around the fire-box. Its form may be best understood by reference to Fig. 5, which represents a similar dome, here inafter to be referred to. l

G is a sheet-iron cylinder fitting close over the rim a, and being supported by the dome F, ,the space between it and the outer casing, A, forming an annular passage, H. It reaches to the same height as A.

I is an inverted dome of cast-iron, smaller than F.l It has an opening through its center, ysurrounded by a rim, o, which extends ilpward in the form of a slightly conical tube, and has another rim, d, extending upward around its outer edge. It has a series of short tubes, ff, extending downward from it, which fit over the tubes b b of the dome F, and form passages through both domes, the tubes b b supporting the upper dome.

J is a damper or valve, which is placed in the short tube c.

K is a sheet-iron cylinder fitting over the rim d, and, being supported by the dome, it does not extend quite so high as G. The space between it and G forms an annular passage, L.

M is an inverted dome similar to F, and represented detached in Fig. 5. It has an opening in its center surrounded by a rim, g, which ts over the short pipe c, on which it is supported. lt has a rim, h, which extends upward all round it, and a series of tubes, i i, extending upward, ran ging in a circle around its center.

N is a sheet-iron cylinder fitting on the rim h, and supported by the dome M. It extends upward to the same height as the cylinder K, and there is an annular space, O, between the two.

F, whose form is most clearly shown in Fig. et, is a circular plate of castiron, having an opening through its center surrounded by a rim, j, forming the chimney-seat. It has a rim, k, extending upward around its outer edge, and has a number of short tubes, l l, extending downward and fitting over the tubes t' i, forming passages through it and through the dome.

Q is a sheet-iron cylinder fitting and restingl on the plate P, and running up tothe same height as the cylinders A and Gr. The space between it and N forms an annularpassage,R.

S is the chimney. Betweenit andthecylinder Q is an annular space, T.

U is a cast-iron plate whose form is shown inplan, Fig. 3. It fits down close to the cylinders A, G, and Q, and has openings m m, communicating with H, an opening, a,rwhich communicates with T, and a series of openings, o o, which communicate, by a series of small tubesp p, with the space O, the top rof' arrows in the passages. During its ascent it is brought into contact with an immense amount of heating-surface, being divided in ypassing through the main passages H O T into thin currents, each of which, except the outermost one, passes between two surfaces which are exposed to the re, and being divided by passing through the small tubes into still smaller currents, each of which is entirely surrounded by the heat and ignited gases passing through the flues, a great amount of heat is also communicated to it in passing the inverted domes. As the under part yof the fluespaces through which the products of combustion pass outward and inward, and herein termed the domes,7 are inclined downward toward the center of the stove or furnace or nre-chamber, it will be seen that all solid par ticles of matter-such as ashes, soot, Ste., falling upon these surfaces, will roll down and be returned to the iire-chamber-and it will be obvious that this will be the case whether the air-passages be arranged in the manner herein described or in any other manner, with the view to obtain an extended heating-surface, and hence I wish it to be distinctly understood that I do not limit myself to the use of the two parts of my invention in connection,

obtainedby the union of the two.

openings q for use, its ascent being shown by v although in my belief the best results will be The abovedescribed arrangement of cylinders may be continued with an increased number similarly connected to form a greater number of air passages and iiues if thought desirable, As many may be employed as will reduce the temperature in the chimney so much that no advantage could be gained by further increase. Instead of cylinders, tubes of polygonal, elliptic, or other forms may be employed, and instead of domes F l M P frustums of cones may be used. As the heat will have the greatest degree of intensity near the center of the stove, it is advantageous to induce a stronger current of air through those passages nearest it than through those nearest the outside. This I accomplish by the following means: By making the sum of the areas of the tubes b b ff greater than that of the openings m m at the top of the passage H, and the sum of the areas of the passages T much greater than that of H, I induce a strong current through b b ff, where the heat is extremely intense, which weakens that 'in H and sends more air into the space above the dome I. Again, by making the sum of the areas of the tubes z' z' greater than that of the tubes p p or of the openings o o, and the areas of T greater than that of o, I induce a strong current through z' fi, which weakens that through o and strengthens that in T. Thus the air'has tendency to rush in stronger currents toward they center of the stove.

What I claim as my invention, ailddesire to secure by Letters Patent, is

1. Making the bottom plates of the luef spaces of air-heating furnaces or stoves for the passage of the products of combustion outward or-inward among or around the air-passages inclining inward and downward toward the lire-chamber, substantially as described, for the purpose of facilitating the increase of the heating-surface without the inconvenience of the accumulation of ashes,

scot, and other solid matter on such plates,

J. M. THA'rcHnn.

Witnessesz' WM. H. BIsHoP, ANDREW DE LACY.

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