US2564713A - Coal coking and burning magazine stove - Google Patents

Description

Patented Aug. 21, 1951 COAL COKING AND BURNING MAGAZINE STOVE John 0. Miles, Urbana, Ill., assignor to Board of Trustees, University of Illinois, Urbana, Ill.

Application January 31, 1946, Serial No. 644,563

This invention relates to a coal stove or the like for heating buildings.

All bituminous coal contains large amounts of volatile matter which is not burned completely in the ordinary stove or furnace and is given off in the form of smoke. This not only wastes much of the fuel value of the coal but also results in a dirty atmosphere. Various methods have been proposed for burning the combustible vapors. Most of these methods, however, are not adaptable to simple stoves for the heating of residences.

I have invented a light-weight, inexpensive stove which uses the downdraft principle of burning to consume the smoke. This new stove requires a minimum of attention and can be easily regulated so that the heat given off can be controlled. The new stove provides for a storage space which can be filled with coal and will then require no attention for considerable periods of time.

With the new coal stove it is now possible to heat small homes emciently and at extremely low cost. All the combustible matter of the fuel is burned and there is very little or no smoke given off at any time.

The invention will be described as related to the embodiment of the same set out in the accompanying drawings. Of the drawings Fig. 1

is a partial vertical section taken substantially through the center of the stove; Fig. 2 is a'horizontal section taken along line 2-2 of Fig. 1; Fig. 3 is a horizontal section taken along line 33 of Fig. 1; Fig. 4 is a horizontal section taken along line 4-4 of Fig. 1; and Fig. 5 is a horizontal section taken along line 55 of Fig. 1.

The coal stove shown in the accompanying drawings comprises a shell ill, a base H, and an,

exhaust pipe I2 for the escape of burned gases. The shell I is of substantially cylindrical shape except for a flat rear portion l3 inclined downwardly and inwardly. This fiat rear portionextends from near the top to approximately the mid-portion of the shell.

On the inside of the shell there is located a flat plate l4 arranged substantially parallel to and spaced from the flat rear portion l3 of the shell. This plate I4 is supported on four posts l and has its bottom end I6 extending into the stove. The top edge of the plate M is spaced from the top portion ll of the shell.

.At the top of the shell I9 there is located a radiator l-8 communicating with the exhaust pipe l2. This radiator is separated from the firebox J9 that is located in front of the fiat plate l4.

7 Claims. (Cl. 126-73) Immediately beneath the lower edge of the flat plate Hi there is located a fiat grate 20 formed of three substantially rectangular grate bars 2|, 22, and 23. This grate defines the bottom of the firebox. 7

At the front of the stove there is located a combustion chamber 24 formed of refractory elements 25 against the shell 10 and a second set of refractory elements 26 spaced from the first set 25. The top of the combustion chamber 24 communicates with the radiator l8, while the bottom of the combustion chamber communicates with the firebox [9. The bottom entrance to the combustion chamber 24 is formed by an inclined shoulder 21 of refractory material extending beyond the inner edge of the combustion chamber and into the firebox. The inclined shoulder 21 forms a constricted entrance 28 to the combustion chamber 24.

Secondary air is admitted upwardly to the combustion chamber 24 through an air passageway 29 at the front of the stove and beneath the inclined shoulder 21. This secondary air passageway is formed by refractory or metal elements 30 held in spaced relationship from the shell I0. The top of the refractory elements 30 as shown is spaced from the shoulder 21 and inclined inwardly and upwardly to form an air opening 31.

The bottom portion of the flat plate I4 contains a number of holes or perforations 32. These holes extend upwardly to a point substantially even with the bottom of the refractory elements 26 forming the combustion chamber 24. The rear inclined portion l3 of the shell [0 contains air ports 32a and 321) with both ports covered by an adjustable damp-er 33. The air ports 32a and 32b are formed by a division strip 14a extending across the fiat plate I4. Air enters the port 32a and flows upwardly over the upper end of the fiat plate [4 and down along the flat plate into the under-grate portion 34 of the stove. The air flows through port 32b, down along plate 14, through the holes 32, up through the grates 20, and up through the secondary air passageway 29 and openings 31 and 28 into the combustion chamber 24. When the furnace is in operation and filled with coal the firebox I9 will be divided into a coke-burning zone 35 extending from the grates to the entrance 28 to the combustion chamber 24, a coking zone 36 above the coke-burning zone 35, and an uncoked coal zone 31 above the coking zone 36. Air enters the coke-burning zone 35 through the grates 20 around the bottom portion of the inclined plate [4 and through the lower holes 32. Air enters the coking zone 36 through the upper holes 32. Air enters the uncoked coal zone 31 around the upper edge of the fiat plate I4. The top front portion ll of the shell l adjacent this upper edge is provided with a downwardly extending flange 38 to direct the air in a generally downward direction through the uncoked coal zone 31.

At the top of the stove and beside the radiator l8 there is located an opening 39 for the introduction of coal into the firebox [9. This opening 39 is normally closed by a hinged door 40 that opens toward the radiator 18. This hinged door may be opened by means of a handle 4|. Adjacent the opening 39 is a second opening 42 between the firebox l9 and the radiator 18. This second opening 12 is normally kept closed by a sliding door 43 held in side brackets 44. The two doors 40 and 43 are connected by a bar 45 hingedly mounted at one end on the first door 40 and also hingedly mounted at the other end on the sliding door 43. With this construction the two doors are opened and closed substantially simultaneously.

Each of the grate bars 2 l, 22, and 23 which define the bottom of the firebox are hingedly mounted at points beneath their mid-sections. The first grate bar 2! at the front of the firebox is provided with a relatively short downwardly extending bar 48. The second grate bar 22 is provided with a similar bar 4! of appreciably greater length, and the third grate bar 23 is provided with a similar bar 58 of still greater length. The lower ends of each of these bars, 46, 41, and 48 are rotatably connected by an inclined bar 49. With this arrangement the grates are shaken by moving the inclined bar :9 back and forth, by means of any desired. mechanism. This movement rotates the grate bars 2:, 22, and 23, with the grate bar 2| being rotated through the greatest arc, the second grate bar 22 being rotated through the next greatest arc, and the third grate bar 23 through the smallest arc. This construction is important because the greatest burning rate occurs at the front of the stove, and the grate bar 2| underneath this portion is given the greatest agitation when the grates are shaken. As shown in the drawings the middle grate bar 22 is turned by a handle 59 extending through the shell l0, and this turns the other grate bars 2| and 23.

The under-grate portion of the stove is provided with an ash removal door at the front or back thereof. The radiator l8 has a top opening 52 that is used for clean-out purposes, and this opening is normally kept closed by means of a weighted cover 53.

When the furnace is in operation air enters through the air ports 32a and 32b. The air from port 32a is directed down through the uncoked coal zone 3?. The air from port 3222 is directed laterally into the coking zone 36; another portion of this air is directed laterally into the cokeburning zone 35; a portion of the air is directed upwardly into the coke-burning zone 35; and a final portion of the air is directed up through the secondary air passageway 29 around the shoulder 21, and through the constricted opening 28 into the combustion chamber 2 The burning gases ordinarily extend through the combustion chamber 24 and into the radiator 18. In this chamber all of the volatile combustible products are consumed, leaving only the gases fromthe combustion to be exhausted out the pipe I2.

Having described my invention as related to the embodiment shown in the accompanying drawings, it is my intention that the invention be not limited by the details of description unless otherwise specified but rather be construed broadly within its spirit and scope as set out in the accompanying claims.

Iclaim:

1. A coal stove comprising a shell having a front wall inclined downwardly and inwardly; a plate arranged substantially parallel to said front wall for at least the greater part of its length and spaced therefrom; a firebox behind said plate divided into a coke-burning zone at the bottom thereof, a coking zone above said coke burning zone and an uncoked coal zone adjacent the top portion of said plate; said plate having perforations therein communicating only with the cokeburning zone and the coking zone; means forming an air port through said shell opposite said plate and above the coke-burning zone; a grate beneath the lower edge of said plate and forming the lower boundary for said coke-burning zone; means forming a combustion chamber above and laterally displaced from the coke-burning zone; means for directing a portion of the air from said air ports downwardly into the uncoked coal zone; means for directing a portion of the air through said perforations; means for directing a portion of the air upwardly into the coke-burning zone; and means for directing a portion of air upwardly as secondary air into the combustion chamber.

2. The coal stove of claim 1 wherein the upper edge of said plate is separated from the top portion of the shell to provide an air opening into the top of the uncoked coal zone.

3. The coal stove of claim 1 wherein there is provided a constricted neck portion of diminishing cross-section at the bottom entrance to the combustion chamber through which the secondary air enters.

4. The coal stove of claim 1 wherein the top portion of the shell contains a radiator separated from the firebox with the top of the combustion chamber opening into said radiator on one side thereof and a stack for burned gases communicating with an opposite side thereof.

5. The coal stove of claim 1 wherein the top of the firebox contains means forming an open-. ing for the introduction of coal normally closed by a door, and the top portion of the shell contains a radiator separated from the firebox with the top of the combustion chamber opening into said radiator on one side thereof and a stack for burned gases communicating with an opposite side thereof, said radiator having means forming an opening communicating with the firebox and normally closed by a door, said opening between the radiator and the firebox being located beneath the stack.

6. In a coal stove and the like having a firebox formed with a coke-burning zone, the combination comprising: means forming a combustion chamber above one side of the coke-burning zone and communicating therewith at the bottom of the combustion chamber, a bafile at one side of the coke-burning zone and beneath the combustion chamber with the bafile being spaced from the adjacent side of the stove and the bottom of the combustion chamber to form an air passageway, and the top edge of the bafile adjacent said side of the stove being sloped upwardly and inwardly, and a second baille having a portion projecting from the said side of the stove into the space between the first bafile and the bottom of the combustion chamber and spaced from each, said second bafile having an upwardly and outwardly sloped top surface leading to the bottom entrance of the combustion chamber, the said sloped top of the first baffle and projecting portion of the second bafiie forming gradually diminishing constricted air entrances to the cokeburning zone and to the bottom of the combustion chamber.

7. The coal stove of claim 6 wherein the projecting portion of the second baflle extends beyond the inner surface of the first baflie and the inner side of the combustion chamber.

JOHN C. MILES.

REFERENCES CITED UNITED STATES PATENTS Name Date Mayhew June 29, 1869 Number Number Number 6 Name Date Livermore Mar. 11, 1890 Hinstin Feb. 16, 1892 Benster June 1, 1897 Schumann Dec. 24, 1901 Boies et a1 Aug. 30, 1910 Lazzell Dec. 12, 1916 Mersfelder May 11,1920 Wier Nov. 17, 1925 Lowe Sept. 22, 1942 Wingert June 20, 1944 Wingert Dec. 4, 1945 Sanford et a1 July 9, 1946 FOREIGN PATENTS Country Date Austria May 25, 1904 Austria Aug. 26, 1934 Germany June 23, 1904 Great Britain June 18, 1928 Germany Sept. 30, 1933

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