US2186004A - Burner for liquid fuel - Google Patents

Description

Jan. 9, 1940. J, L BREES 4 2,186,004

1 BURNER'FOR LIQUID FUEL 0 l y ,covoon im Patented Jan. 9, 1940 UNITED STATES PATENT OFFICE BURNER FOR LIQUID FUEL James L. Breese, Santa Fe, N. Mex., assigner to Oil Devices, Santa Fe, N. Mex., a limited partnership of Illinois 2 Itlflaims., (Cl. 158-91) My invention relates to an improvement in burners for burning liquid fuels, such as hydrocarbons, and has for one purpose the provision of a-burner which can be turned down to a very small fire, or low draft, without destroying the characteristic mode of combustion described, for example, in my prior issued Patent No. 1,702,929, issued on February 19,1929. I I Another purpose is the provision `of means for permitting low drafts burning with such a burner, while preventing down drafts from upper portions of the combustion chamber, which would disadvantageously affect combustion.

Another purpose is the provision of such means which are adaptable for ready removal to permit easycleaning of the burner and for adjustment of the burner capacity.

Anotherpurpose is the provision of a burner 'for carrying on my characteristic combustion method which constitutes or includes a plurality of superposed burners of varying diameters.

Another purpose is the provision, in connection with one of my burners, of'a lower supplementary burner which may have the functions of 'a pilot light for maintaining combustion during periods when a minimum heat or no heat is desired.

Another purposeis the provision of means forl l locating a lower baille sufficiently low in the burner to maintain a minimum llame as a pilot with a minimum use of fuel.

Anotherr purpose is the provision of means for raising such lower baille to a ylevel suiiicient to render it easy to initiate combustion, while permitting its ready return to turndown position.

Other purposes will appear from time to time in the course of the specification and claims.

The present application is a division of vmy copending application Serial No. 124,695, filed Ti'ebruary 8, 1937.

I illustrate my invention more or less diagrammatically in the accompanying drawing, wherein:

Figure 1 is a vertical axial section;

Figure 2 is a. similar section of a variant form of the device. y

Like parts are indicated by like symbols throughout the specification and drawing.

Referring to the drawing, I generally indicates an outer furnace or heater shell and 2 an inner shell. 3 is a horizontal partition secured -to the inner shell and provided with a central aperture 4. 5 is a preferably removable'baille, with a central aperture 6. 'I is a combustion chamber 55r member, herein shown as generally cylindrical,

self form part of the present invention, but it will be understood that any suitable float chamber or the like may be employed for governing the desired flow of fuel, for example a liquid hydrocarbon fuel, to the bottom 8. y

II is a closure member secured within the shell 2 and provided with apertures I2, which may be in a separate removable plate i3 closingthe central aperture I4 of the member II. I'herein illustrate air inlet apertures I5 in the bottom of the shell 2 and it will be understood that any suitable means, whether by natural draft or forced draft, may be used to supply air to the space between the shells I and 2, which air is caused to ow through the apertures I 5, upwardly through the apertures I 2, and into the space between the member 'I and the shell 2. The member 1 is providedI with an upper row of secondary air inlet apertures I6, herein shown as upwardly and inwardly inclined. A plurality of preferably smaller apertures I1 are shown arranged in rows in a lower portion of the member `l. 'Ihe bottom row I8 is also indicated.

Positioned above the'bottom row I8 is an upwardly movable and removable ring I9, herein shown as a simple annular disc conforming generally to the inner face of the wall 1 and having a central aperture It may normally be positioned in lowest position by permitting it to rest by .gravity upon any suitable inward projections, studs or the like, 2|. V'It desired, there may be a slight clearance of the outer edge of the baille ring', inasmuch as I nd it advantageous to permit the certain flow of air upwardly along the inner face of the wall l. This clearance may vary and may be as much as an eighth to a quarter of an inch if desired. In the form of Figure 2, in the place of the studs 2|, I may provide a lower portion of the chamber of reduced diameter as at 22, which is connected to the portion 1 as by a generally horizontal 'shelf or ledge 23, upon which the baille I9 may rest by gravity when in its lowermost position. I

Y.In the normal operation of the device, the characteristic combustion method of my Patent Number 1,702,929 may be carried on. 'The primary air supply enters through the apertures Il and ward and through the aperture 6 of the' baille 5' and there receives the secondary air supply admitted through the apertures I6. 'I'his produces a iinal mixture which burns and provides the heat for the stove or furnace unit.

l Preferably, whether by natural draft or by any suitable fan or the like, not herein shown, suificient air is admitted for maintaining combustion at a rate sumcient' to give the desired heat. Any suitable control means, thermostatic or otherwise, may be employed for controlling the desired heat produced.

In the event that it is desired to turn down the unit to a minimum heat, or to practically no heat, the air supply is reduced and combustion is correspondingly reduced. In the structure as shown in my Patent Number 1,702,929, there is a limit below which the stove does not operate eiciently. For example, unless a suiiic'ient air supply and sufilcient rate' of combustion is maintained, the secondary air or-the air above the baille 5 tends to eddy back and circulate down into the primary combustion zone, with the result that the balancev between the primary and secondary zones is destroyed and my method of combustion is interrupted, resulting in carbon deposit, and ineiiicient combustion.

I iind that the interpostion of a baille, such as the one shown herein at I9, prevents this down draft and my primary mixing and combustion may be carried on by means of the holes I8, and the secondary air may then be supplied by some or all of the holes I1. In other words, the primary zone moves down to or is limited to the holes below the baille, baille, which previously operated as a' source of primary air, then becomes the source of secondary air. y

When the baille I9 is atthe bottommost position in which it is shown in the figures, the por-l tion of the chamber below thebaiiie becomes a very effective pilot light structure which employs a very small amount of iuel. The smaller the opening 20 in baille I9 the lower the minimum flamevandrthe greater the turndown. There is, however, a critical point in the size oi the aperture taken with the position ofthe bame I9 at which, eventhou'gh it will satisfactorily maintain a ame after the device is in combustion,` it will not permit combustion to initiate.

I initially raise the baille I9. This allows an increased supply of air to enter the space below the bafiie which is important in the initialperiod of combustion.' The size of the central hole 20, which determines the minimum combustion, may be made-quite small, if means are provided for raising the baille during the period of initiation. For example, if I employ a 1 0 inch burner with a. two inch hole in the baille I8 and it is diflicult to light the burner because of insuillcient air in the lowest zone, I simply lift the nd the holes above the suitable handle 42. The lower end of the chain may be secured to the baille I9 by any suitable means. I illustrate for example chain branches -43. It will be understood that a pull on the handie 42 serves .to raise the baiile. The baille may be kept in raised position by engaging the chain ori handle by any suitable abutment mechanism generally indicated at 44. w

It will be realized that whereas I have described a practical and operative device, nevertheless many'changes may be made in size, shape, number and disposition of parts. I therefore wish my drawing to be taken as 'in a broad sense illustrative or diagrammatic rather than as limitirig me to the specic structure herein described and shown.

I claim:

1. A mechanism for burning liquid fuel, which includes a perforated walled chamber having a wall with air admission apertures the/rein, means for admitting a liquid iuel to the chamber, said chamber having an open top, a baille normally located adjacent the bottom of the chamber but above the lowest said apertures, said baille having an aperture therein, the size of the aperture in relation to the form and cubic content of the chamber, and the height of the baille from the chamber bottom, being adapted to maintain combustionwithin the portion of the chamber below I said bafile Whencombustion has been initiated, but being insuiiicient to permit combustion to be initiated', means for bodily raising said baille to -a suiiicient height to permit the initiation of combustion, whereby, when the baille is so raised, additional air inlet apertures'are put in commu.-

4nication with the portion of the chamber below said baille, and for holding said baille iixed in adjusted position.

2. In a device for burning liquid fuels, a mixing pot having a perforate wall, a baiiie adapted ,l to divide said pot into an upper and-a lower chamber, said baiiie being apertured to put said two -chambers into communication with eachother, `means for normally supporting said .baille in a lower portion of said pot, whereby the volumetric capacity of the chamber below the baille is substantially less than the volumetric capacity of the chamber above said baille, means for bodily raising said baille to a higher position and fv r thereby changing the relative volumetric ca ties of the two chambers,'and at the same time placing the space below the baffle in communication with additional apertures, whereby the airl supply to the lower chamber is increased, as well asits volumetric capacity, and means for iixing the baille in adjusted pitio'n.

JAMES L. BREESE.

Images