US2300486A

US2300486A - Coal gas stoning range

Info

Publication number: US2300486A
Authority: US
Publication date: 1942-11-03
Anticipated expiration: 1959-11-03

Description

Nov. 3, 1942.

N.-H. CARGILE COAL GAS BURNING- RAN-GE Filed Nov. 22, 1940 a Sheets-Sheet l Neil H aaryize.

Nov. 3, 1942.- N. H. CARGILE coAL GAS BURNINGRANGE Filed Nov. 22, 1940 3 Sheets-Sheet 2 {Veil h. @aryiZe Nov. 3, 1942.

N. H. QARGILE COAL GAS BURNING RANGE 3 Sheets-Sheet 5 Filed Nov. 22, 1940 Patented Nov. 3, 1942 T OFFIC 13 Claims.

My invention relates to the art of coal ranges or cooking stoves, exemplified by U. S. Patents #51224, November 28, 1865, #112,377, March 7, #1871, 158,653, January 12, 1875, #179,776, July 1, 1876, and #377,876, February 14, 1888.

One of the objects of the present invention is to improve the ranges or cooking stoves of the prior art so as to produce a range, etc, in which fuel consumption is reduced to a minimum and heating or cooking efficiency raised to a maximum.

Another object is to provide a range or cooking stove of such construction that it will not only burn hard or soft coal with great efiiciency but the range, etc., will also be of a compact construction and of pleasing appearance so as to bar monize with modern kitchen practice.

Again, it is an object to provide a range or cooking stove in which the combustion is so complete that .the formation of heavy or black smoke and soot is practically eliminated, thereby permitting the use of shallower flues about the oven chamber and thus providing for an increase in the oven space, for a given over-all dimension, than is possible to obtain with the structures of the prior art.

Another object of my invention is to provide a magazine feed burner with which the fire may be held for long periods of time, with which burner and simple air controls the heat to the cooking top and to the oven is easily and quickly regulated or controlled, and with which arrangements it is possible and practical, at all times, to have a quick, hot fire available for cooking by stirring up the fuel in the magazine, shaking the grate and opening the air control dampers, and from time to time adding a small amount of fuel.

More specifically, the invention has for its objects: to provide a cooking stove or range having, at one side of the oven chamber, a closed fuel magazine with a grate at its bottom and having gas ports in one side wall a short distance above the grate level, through which ports the gases from the ignited fuel bed pass into a gas-burning chamber which is located between the magazine and the adjacent wall of the oven chamber; to provide auxiliary or secondary air for combus tion to enter the gas-burning chamber at about the level of and on the side opposite the gas ports to effect full combustion of the gases; to provide a slanting grate so designed and positioned with respect to gas ports that the air passing through the grate, and the gases and products of combustion from the fuel, cause a side-wise flow to take place across the bottom portion of the magazine, by virtue of which there will be a tendency to hold the actual burning lower in the magazine than would be the case if there were a fiat grate through which the air entered vertically and then had to turn through right angles to go out-the side ports or pass under a division plate; to provide for passing these gases around the oven before discharging same to a smoke box and chimney flue; to provide for the admission of a proper supply of overdraft air into the magazine adjacent its top, sufiicient in quantity to prevent formation in the fuel body of tars in sufiicient amount to clog the fuel and to cause a downflow of the products of distillation; and to provide two air admission means under control of two valves for governing the primary, overdraft and secondary air supplies. v

Other objects will in part be obvious and in part be pointed out hereinafter.

To the attainment of the aforesaid objects and ends the invention still further resides in the novel details of construction, combination and arrangement of parts, all of which will be first fully described in the following detailed description, and then be particularly pointed out in the appended claims, reference being had to the accompanying drawings, in which:

Fig. l is a perspective view of a range or cooking stove embodying my invention.

Fig. 2 is a view similar to Fig. l with parts broken away, the oven and warming chamber doors open and the fuel feed door open.

Fig. 3 is a vertical section of the line 3'3 of Fig. 4.

Fig. 4 is a cross-section taken substantially on the line 4-4 of Fig. 3, but showing a modified positioning of holes 32 with respect to ports 36.

Fig. 5 is a cross-section on the line 5 5 of Fig. 3.

In the drawings, in which like numerals of reference indicate like parts in all of the figures, it

will be seen that the outer wall of the range is composed preferably of an outer shell I, and. an inner shell 2 separated by an air space 3; a top casting 4 fits on this wall and a bottom 1 is provided as best shown in Figs. 3 and 4.

Within the space bounded by the outer wall of the range and spaced from the sides of the same is an oven shell 5, the back wall of which is constituted by a part of the outer wall of the range and the front of which is closed by a drop door It].

Located to one side of the oven and spaced therefrom to leave a side flue is a transversely disposed vertical partition 6 formed, preferably, of two metal plates with rock wool insulation between them. 7

Beneath the oven and spalced from the bottom of the oven shell 5 is another plate 24 with rock wool insulation between it and the bottom 7, the space between shell 5 and plate 24 constituting a continuation of the flue about the oven. A partitition or baffie flue strip 25 extends partway across from the back wall to prevent the products of combustion passing directly to the bottom flue opening 2 6, see Figs. 3 and 5.

The top of the shell is spaced from the level of the top casting 4 to form the top flue of which the side flue is a continuation. A top flue opening 27 to smoke box 29 is provided adjacent the entrant end of the oven embracing flue (see Figs. 3 and 5), and this opening 21 may be closed by a sliding damper 28 after the fire has been started as will be clearer later.

At the other side of the oven there is provided a space which contains the. fuel magazine and the combustion chamber for the gases. Access to this space may be had through a front door 9. In this space is a transverse vertical partition 3i that extends up from bottom l to about one half the height of the oven where it is bent over to the oven shell and, with that shell and its flange 5 at the front, and the back wall of shell 2, constitutes a secondary air chamber into which air is admitted via a set of holes 33 of predetermined aggregate area, and from which the air passes through inclined holes 32.

Above the partition 3| and set on the upper inturned portion of the same is a flame back 34 of fire-brick or fire-clay which lies against the upper part of the side wall of shell 5 to protect the same from direct flame action.

To the left (in Fig. 3) of the secondary air chamber and of the fire-clay flame back 34 is the fuel magazine. This comprises the inner wall 35 of heavy cast iron and extends from the top of the range to a place below openings 32. The outer wall of the magazine lies adjacent the side wall of the inner shell and includes a downwardlyinwardly inclined portion 37 terminating at the grate carrying casting 38, as does also wall 35. The front and back walls 48 of the magazine preferably diverge downwardly or may be vertical if desired from the top of the range (see Fig. 4) and terminate at the grate 39. Opposite the outlets (holes) 32, the wall 35 has vertically elongated ports 35 through which the gases from the ignited fuel bed pass into the gas-burning or combustion chamber, i. e. the space between wall 35 and flame back 34. The outlets 32 are, preferably, staggered with respect to the ports 36 (see Fig. 4) although if desired they may lie opposite the ports (Fig. 3) or some may be staggered and some lie opposite if found desirable.

46 designates partitions which cut off the flow of air directly to the gas-burning or combustion chamber between the front and back of the magazine. These partitions 46 have holes 48 which communicate with ducts 51 that convey overdraft air to small openings 49 in walls 40 near the top of the magazine (see Figs. 3 and 4).

At the upper part of the magazine are air inlets 5| which are controlled by a damper 52 and constitute what I call the high-speed air control, the purpose of which is to make the fire burn faster when it is first lighted or when the drafts are opened and the fire in the burner is burning at its very lowest rate after the drafts have been closed several hours to cut down or reduce the heat or fire, as in a stand-by when the range is not in use.

50 designates air holes through the back Wall of the stove to admit a small constant supply of secondary air regardless of the dampers. When the burner is burning at a low rate with the highspeed air controlclosed, and the main air regulator closed, these secondary air holes supply sufficient air to the air chamber to pass through the air ports 32 to give proper combustion at this stage of operation.

The grate 39 has a handle M to which a shaker (not shown) may be attached When door 9 is open and it is desired to shake the grate.

An ash box or pan 42 is supported, between suitable guides 53, on bottom I below grate 33.

Opposite the inclined wall 37 is the air inlet 44 that is controlled by a suitable valve 45 and constitutes the main air supply and control unit.

To the right (in Fig. 3) of the wall 6 is a chamber, closed at the front by a door II, which may serve as a compartment for a water heating reservoir, a warming chamber or be used for any other purpose desired.

The top of the range has removable sections l5, l6 and I1, and removable lids i8 and 29 (Fig. 1). The magazine is filled through a suitably mounted door 19. A clean-out door.l2 is provided between the bottom of oven door l0 and the skirt 8.

The several doors 9, i3 and II have handles l3 and door I2 has a knob I4 (Fig. 1).

The range may have an upward back shield 53 on which may be mounted a shelf with a cooking timer and salt and pepper box assembly 2 I, and a cooking top light with shield 22 if desired, and the range may be mounted on suitable legs 23 as shown.

The smoke box 23 has a connection 36 to which the chimney flue may be attached.

Operation The fire is started by putting paper and kindling in the bottom of the magazine above grate 39. After the paper and kindling have been placed in the bottom of the magazine, the rest of the magazine is filled with lump coal.

The fuel door 13 is then closed. This door fits tight so that no appreciable amount of air leaks in around the door and no smoke or fumes escape into the room.

High-speed air regulator 52 and damper 28 are opened. The main air regulator 45 is opened. The fire is lighted from the ash pit by holding a lighted piece of paper beneath the grate.

The top direct damper 28 is opened when the fire is first lighted, allowing the direct draft of the chimney to draw on the fire. After the fire has been burning about five minutes, the damper 28 is closed, thereby forcing the heat and products of combustion around the oven as indicated by the arrows in Figs. 2 and 3. The hot products of combustion travel between the top of the oven and the cooking top, down the right hand side of the oven, then under the oven past the flue strip 25, and out the bottom flue opening 25 where the burned gases, etc., are discharged into the back smoke box 29 to which the smoke pipe (not shown) is connected.

The air regulator 45 controls the amount of air, primary, which goes through the grate 39, overdraft which goes through the holes 49, and sec ondary air, which goes through holes 33, through the secondary air chamber, and out through the holes 32 into the gas-burning or combustion chamber near the base of the flames, and between the flames burning through the port holes 36. The air regulator 45 controls such operation when the high-speed air regulator is closed.

A portion of the air admitted by the regulator 45 is drawn through the holes 48, ducts 4'! and holes 49 into the magazine on top of the coal therein. This air (secondary air) is arranged so that just enough is drawn in to cause enough down-draft through the fuel to carry the gases and other distillates from the coal above the combustion zone, down through the fuel and discharge the same through the port holes 36 and burn clean. The coal in the magazine is coked as it feeds down to the burning zone near the grate 39 and port holes 36.

The magazine holds sufiicient coal to last all day and by replenishing the fuel, closing the air regulator, the fire may be started the next morning and quickly heat up the range by simply stirring up the coke and coal in the magazine, adding a small amount of coal and opening the drafts. By admitting all the air for combustion through the regulator 45, it is very easy to control the fire and the heat for the oven, something that is very difiicult to accomplish satisfactorily with the ranges of the prior art.

The high-speed air damper 52 is opened when one wishes to have the fire come back quickly after it has been banked or standing by; this damper is not open after the range has become heated, as this extra amount of air, or the extra amount of down-draft, is not required except during the starting or recovery period because the lower air regulator 45 supplies sufficient primary air for the grate and for the over-draft air passing through the holes 49, and at the same time sufiicient secondary air, in addition to the fixed secondary air openings 50 in the back of the range, to provide enough air for a satisfactory burning rate for the range, and to prevent clogging in the magazine, and to carry the products of distillation of the fuel bed through the incandescent fuel in the bottom of the magazine and out through the ports where they are properly burned. By carrying the products of distillation from the coal which is being coked above the bed of incandescent coke, through the incandescent fuel bed, either in a downward or sidewise direction, these gases are raised to ignition temperature, so that when they have passed through the constricted area port holes 36 they are burned promptly in the presence of a sufficient supply of secondar air.

By diverging the walls 46 downwardly, the bridging action of the fuel is reduced to a minimum allowing a downward movement of the coal as it is consumed.

By a proper designing and proportioning of the areas and positions of the

holes

32, 33, ports 36 and holes 49, with regard to the fuel used (hard or soft coal), it is possible to use a single air regulator 45 and yet maintain high efficiency of operation. operating skill to a minimum and make the range practically fool-proof.

By carrying the products of combustion, gases, etc., through constricted-area port holes, the burning rate of the fire may be more quickly regulated and may be definitely controlled, whereas in a magazine feed that does not constrict the outlet through open port holes, or where the magazine has an open slot or partition or side wall out from under which the flame burnsas in the stoves of the aforementioned patentsit is very difficult to regulate or control the burning rate and to get clean burning.

From the foregoing description, taken with the accompanying drawings, it is thought the construction, operation and advantages of my improved range will be clear to those skilled in the art.

What I claim is:

1. In a range, an enclosing body having a top The two air regulators reduce and a bottom, an oven shell in said body, said body having a space to one side of said oven shell, which space contains a fuel magazine and a separate gas-burning chamber alongside said magazine, said magazine comprising side walls, front and back walls, and a grate at the bottom, the side wall of said magazine which faces the oven being spaced therefrom and having gas ports above but adjacent the grate, a secondary air duct in said space betweeen said wall with the gas ports and the oven and having air discharge holes adjacent said ports for admitting secondary air into the gas-burning chamber with the gases from said ports to complete the combustion of said gases, said magazine having at least one over-draft air hole near its top for admission of air above the coal in the magazine, partitions separating said gas-burning chamber from the space below the grate, a duct for conveying overdraft air to said at least one over-draft air hole, and an air regulator for regulating the air passing through said grate, said secondary air ducts and said over-draft air hole, said range having a flue outlet for passing the products of combusiton to a chimney fiue and means to divert the products of combustion about the oven before passing to the fiue outlet.

2. In a range of the character described, an outer casing enclosing an oven shell, and a coal magazine at one side of the oven shell and enclosing a gas-burning chamber located alongside the magazine and an ash chamber, a front door for the combustion and ash chambers, a front door for the oven, a duct for carrying the products of combustion over the top, down one side and under the oven shell to a fine outlet in said outer casing, said magazine comprising two side walls, a front wall and a back wall and a bottom grate, the side wall of the magazine facing the oven shell being spaced from the same to provide a gas-burning space alongside the magazine and being provided with flame ports adjacent the grate, a secondary air duct adjacent the oven and having air discharge holes directed upwardly toward said ports, an insulation fiame back above said holes and held beside the oven shell, said secondary air duct having airadmitting holes communicating with the space below the grate, said magazine having a tight top door and having at least one over-draft airadmitting hole in one wall above the coal level, and an air duct for conveying air from the space below the grate to said over-draft air hole, and an air regulator for admitting air into the space below the grate for supplying air to the fire through the grate and for supplying air to said secondary air duct and to said over-draft air hole, and means to discharge the products of combustion from the range.

3. A coal-burning range which includes an outer casing, a top casting and a bottom, an oven shell in said casing and spaced from one side wall thereof, a vertical cross partition at the other side of the oven shell and spaced from the same to provide a down-flow flue, said oven shell being spaced from the top casting to provide a top cross flue from one side of the oven to the other, said shell being spaced from the bottom to provide a bottom flue beneath the shell, there being an outlet from the bottom flue for products of combustion, a coal magazine located in the space between the oven shell and the first mentioned side wall of the casing, said magazine comprising front, back and side walls, a bottom grate and a tight top door, the side wall of the magazine which faces the oven being spaced from the same and including a lower portion in clined downwardly toward the oven, a secondary air duct located between the oven and said inclined lower portion, said inclined lower portion having flame passing ports and said secondary air duct having air holes adjacent said ports for directing the secondary air upwardly and toward said ports, said ports and secondary air duct holes being staggered, a flame back located against the oven and above said secondary air duct, said magazine having an over-draft air hole in its wall at about the coal top-level, partitions to separate the space around the magazine into an upper part and a lower part, the lower part being in communication with the grate and the inlet only of said secondary air duct, another air duct to effect communication between said lower part and said over-draft air hole at the top of the magazine, and air regulating and admitting means for said lower part.

4. A coal-burning range which includes an outer casing, a top casting and a bottom, an oven shell in said casing spaced from one side wall thereof, a vertical cross partition at the other side of the oven shell and spaced from the same to provide a downflow flue, said oven shell being spaced from the top casting to prove a top, cross flue from one side of the oven to the other, said shell being spaced from said bottom to provide a bottom flue beneath the shell, there being an outlet from the bottom flue for products of combustion, a coal magazine located in the space between the oven shell and the first mentioned side wall of the casing, said magazine comprising front, back and side walls, a bottom grate and a tight top door, the side wall of the magazine which faces the oven being spaced from the same and including a lower portion inclined downwardly toward the oven, a secondary air duct located between the oven and said inclined lower portion, said inclined lower portion having flame passing ports and said secondary air duct having air holes adjacent said ports for directing the secondary air upwardly and toward said ports, a flame back located against the oven and above said secondary air duct, said magazine having an over-draft air hole in its wall at about the coal top-level, partitions to separate the space around the magazine into an upper part and a lower part, the lower part being in communication with the grate and the inlet only of said secondary air duct, another air duct to eflect communication between said lower part and said over-draft air hole at the top of the magazine, and air regulating and admitting means for said lower part.

5. A coal-burning range which includes an outer casing, a top casting and a bottom, an oven shell in said casing spaced from one side wall thereof, a vertical cross partition at the other side of the oven shell and spaced from the same to provide a down-flow flue, said oven shell being spaced from the top casting to provide a top cross flue from one side of the oven to the other, said shell being spaced from said bottom to provide a bottom flue beneath the shell, there being an outlet from the bottom flue for products of combustion, a coal magazine located in the space between the oven shell and the first mentioned side wall of the casing, said magazine comprising front, back and side walls, a bottom grate and a tight top door, the side wall of the magazine which faces the oven being spaced from the same and including a lower portion inclined downwardly toward the oven, a secondary air duct located between the oven and said inclined lower portion, said inclined lower portion having flame passing ports and said secondary air .duct having air holes adjacent said ports for directing the secondary air upwardly and toward said ports, a flame back located against the oven and above said secondary air duct, said magazine having an over-draft air hole in its wall at about the coal top-level, partitions to separate the space around the magazine into an upper part and a lower part, the lower part being in communication with the grate and the inlet only of said secondary air duct, another air duct to effect communication between said lower part and said over-draft air hole at the top of the magazine, air regulating and admitting means for said lower part, and a high-speed damper-controlled over-draft air admitting means to the upper part of the magazine.

6. In a range having an oven shell over which heat and products of combustion pass to a flue, means for generating heat by combustion of coal and coal gas, said means comprising a chamber in the range, a .fuel magazine in said chamber, said magazine having a top fuel door and bottom grate, the cross-sectional area of the magazine increasing from the top door toward the grate, said magazine including a heavy wall on the oven side which wall adjacent the grate has gas and flame ports, a secondary air box located between said heavy wall and the oven at the lower end of said heavy wall, said air box having air inlets, and having air outlet holes directed upwardly and toward said flame ports for feeding secondary air to the flames, a flame back above said air box protecting the oven against direct flame action, partitions between the magazine and the front and back of the range to divide said chamber into a lower part and an upper part, the lower part being in direct communication with the grate and the inlets of the air box, said magazine having an over-draft air hole near its top, a duct from the lower part of said chamber to said over-draft air hole, and means to admit air into said lower part and regulate the same.

'7. In a range having an oven shell over which heat and products of combustion pass to a flue, means for generating heat by combustion ofcoal and coal gas, said means comprising a chamber in the range, a fuel magazine in said chamber, said magazine having a top fuel door and a bottom grate, the cross-sectional area of the magazine increasing from the top door toward the grate, said magazine including a heavy wall on the oven side which will adjacent the grate has gas and flame ports, a secondary air box located between said heavy wall and the oven at the lower end of said heavy wall, said air box having air inlets, and having air outlet holes directed upwardly and toward said flame ports for feeding secondary air to the flames, a flame back above said air box and protecting the oven against direct flame action, partitions between the magazine and the front and back of the range to divide said chamber into a lower part and an upper part, the lower part being in direct communication with the grate and the inlets of the air box, said magazine having an over-draft air hole near its top, a duct from the lower part of said chamber to said over-draft air hole, and means to admit air into said lower part and regulate the same, and a controlled high-speed air admitting means to the upper part of the magazine.

8. In a range having an oven shell over which heat and products of combustion pass to a flue, means for generating heat by combustion of coal and coal gas, said means comprising a chamber in the range, a fuel magazine in said chamber, said magazine having a top fuel door and a bottom grate, the cross-sectional area of the magazine increasing from the top door toward the grate, said magazine including a heavy wall on the oven side which wall adjacent the grate has gas and flame ports, a secondary air box located between said heavy wall and the oven at the lower end of said heavy wall, said air box having air inlets, and having air outlet holes directed upwardly and toward said flame ports for feeding secondary air to the flames, a flame back above said air box protecting the oven against direct flame action, partitions between the magazine and the front and back of the range to divide said chamber into a lower part and an upper part, the lower part being in direct communication with the grate and the inlets of the air box, said magazine having an over-draft air hole near its top, a .duct from the lower part of said chamber to said over-draft air hole, and means to admit air into said lower part and regulate the same, some of said air box inlets communicating directly with the atmosphere and the others communicating with the lower part of said chamber.

9. In a range having an oven shell over which heat and products of combustion pass to a flue, means for generating heat by combustion of coal and coal gas, said means comprising a chamber in the range, a fuel magazine in said chamber, said magazine having a top fuel door and a bottom grate, the cross-sectional area of the magazine increasing from the top door toward the grate, said magazine including a heavy wall on the oven side which wall adjacent the grate has gas and flame ports, a secondary air box located between said heavy wall and the oven at the lower end of said heavy wall, said air box having air inlets, and having air outlet holes directed upwardly and toward said flame ports for feeding secondary air to the flames, a flame back above said air box and protecting the oven against direct flame action, partitions between the magazine and the front and back of the range to divide said chamber into a lower part and an upper part, the lower part being in direct communication with the grate and the inlets of the air box, said magazine having an over-draft air hole near its top, a duct from the lower part of said chamber to said over-draft air hole, and means to admit air into said lower part and regulate the same, and a controlled high-speed air admitting means to the upper part of the magazine, some of said air box inlets communicating directly with the atmosphere and the others communicating with the lower part of said chamber.

10. In a cooking and baking range having a burner chamber, partitions dividing said burner chamber into a top part and a bottom part, a coal burner in said chamber and comprising a magazine having side and end walls and a bottom grate, one of said side walls having gas ports adjacent the grate end of the magazine, said grate lying at an acute angle to the ported side wall, a secondary air chamber in said burner chamber spaced from said ported wall and having air outlets directed toward said ports and having air inlets communicating with the bottom part of saidburner chamber, a main air control means to admit air to the bottom part of said burner chamber, and at least one over-draft air duct for effecting communication between the lower part of said burner chamber and the upper part of said magazine,

11. In a cooking and baking range having a burner chamber, partitions dividing said burner chamber into a top part and a bottom part, a coal burner in said chamber and comprising a magazine having side and end walls and a bottom grate, one of said side walls having gas ports adjacent the grate end of the magazine, said grate lying at an acute angle to the ported side wall, a secondary air chamber in said burner chamber spaced from said ported wall and having air outlets directed toward said ports and having air inlets communicating with the bottom part of said burner chamber, a main air control means to admit air to the bottom part of said burner chamber, and at least one over-draft air duct for effecting communication between the lower part of said burner chamber and the upper part of said magazine, said secondary air chamber having means to admit a predetermined constant supply of air direct from atmosphere.

12. In a cooking and baking range having a burner chamber, partitions dividing said burner chamber into a top part and a bottom part, a coal burner in said chamber and comprising a magazine having side and end walls and a bottom grate, one of said side walls having gas ports adjacent the grate end of the magazine, said grate lying at an acute angle to the ported side wall, a secondary air chamber in said burner chamber spaced from said ported wall and having air outlets directed toward said ports and having air inlets communicating with the bottom part of said burner chamber, a main air control means to admit air to the bottom part of said burner chamber, at least one over-draft air duct for effecting communication between the lower part of said burner chamber and the upper part of said magazine, and a high-speed over-draft air admitting and controlling means to the upper part of said magazine.

13. In a cooking and baking range having a burner chamber, partitions dividing said burner chamber into a top part and a bottom part, a coal burner in said chamber and comprising a magazine having side and end walls and a bottom grate, one of said side walls having gas ports adjacent the grate end of the magazine, said grate lying at an acute angle to the ported side wall, a secondary air chamber in said burner chamber spaced from said ported wall and having air outlets directed toward said ports and having air inlets communicating with the bottom part of said burner chamber, a main air control means to admit air to the bottom part of said burner chamber, at least one over-draft air duct for effecting communication between the lower part of said burner chamber and the upper part of said magazine, and a high-speed over-draft air admitting and controlling means to the upper part of said magazine, said secondary air chamber having means to admit a predetermined constant supply of air direct from atmosphere.

NEIL H. CARGILE.