US2985234A - Swirl burner - Google Patents

Description

y 1961 c. E. GOLDEN 2,985,234

SWIRL BURNER Filed July 27, 1959 2 Sheets-Sheet 1 FIG../

INVENTOR. CARL E. GOLDEN A TTO/PNEVS y 1961 c. E. GOLDEN 2,985,234

SWIRL BURNER Filed July 27, 1959 2 Sheets-Sheet 2 INVENTOR. CARL E. GOLDEN BGYZZ/W r W A 7' TORNE rs My invention relates to means primarily useful in mixing combustible gas with air for combustion in the immediate vicinity of the burner, and is particularly concerned with such a burner which operates Well on butane and can easily and readily be installed in or adapted to furnaces of the customary type.

It is an object of my invention to provide a burner which has a very large capacity relative to other mechanisms of comparable size and weight.

An additional object of the invention is to provide a swirl burner in which the size of the flame can be varied from time to time.

A still further object of the invention is to provide a burner in which the homogeneous intermixture of fuel gas and air is fostered.

A still further object of the invention is to provide a swirl burner with a pilot or maintenance flame which burns satisfactorily despite wide variations in the volume of flow through the burner.

An additional object of the invention is to provide a swirl burner which can very economically be made, sometirries'largly with standard plumbing parts.

A still further object of the invention is to provide a swirl burner which is extremely simple, economical to construct and maintain and is capable of protracted, trouble-f-ree operation. a

Another object is to provide a generally improved swirl burner.

Other objects, together with the foregoing, are attained in the embodiments of the invention described in the accompanying description and illustrated in the accompanying drawings, in which:

Figure l is a side elevation of one form of swirl burner constructed pursuant to the invention.

Figure 2 is a side elevation of part of a modified form of swirl burner.

Figure 3 is a cross-section to an enlarged scale of the swirl burner of Fig. 1, the plane of section being on a diameter and being vertical.

Figure 4 is a plan of the burner insert, or disc, shown in Figure 3, with the damper removed.

Figure 5 is a cross-section, the plane of which is indicated by the lines 5--5 of Figure 4.

Figure 6 is a cross-section, the plane of which is indicated by the lines 66 of Figure 4.

Figure 7 is a plan comparable to Figure 4 but showing a still further modified form of swirl burner, with the damper in position.

While the burner pursuant to the invention can be easily embodied in a number of ditferent ways and can be varied pursuant to the prospective conditions of operation, it has successfully been incorporated in the various forms shown herein.

Particularly as disclosed in Figure 1, the device is inclusive of a venturi body 6 having an air opening 7 at- A gas conduit United StatesPate nt "ice 11 feeds into the opening 7, being supported suitably therein. An air inlet regulating disc 12 is adjustable along the length of the threaded gas conduit 11 and is locked in position by suitable nuts 13. As so far described, the structure is virtually standard. In operation, gas issuing from the conduit 11 entrains atmospheric air through the large end 7 and carries the mixture through the tube 6 for discharge adjacent the threaded end 9.

Pursuant to the invention and in an installation in which the tube 6 is horizontal and a vertically extending flame is desired, the end of the tube 6 is provided with a standard elbow 16. This is threaded over the threads 9 at the extremity of the tube 6 and is stopped with its upper flange 17 in a horizontal plane and with the customary elbow opening extending upwardly. Within the flange 17 the standard elbow 16 is either formed with or is especially machined to provide threads 18 extending for a substantial distance inwardly from the planar top 19 of the elbow 16 to end at a point well within the hollow interior 21 of the elbow.

Designed to engage the threads 18 are complementary threads 22 on the periphery of a disc 23. Conveniently, the disc is made of cast iron and is defined between an outer planar face 24 and an inner planar face 26. Preferably, the thickness of the disc, that is, the distance between the faces 24 and 26, is somewhat less than the total length of the threads 18. The disc 23, in its preferred form, is provided with a plurality of helical gas conduits 27 preferably evenly spaced around the interior of the disc and affording swirling gas passages from the interior to the exterior thereof. Conveniently, the openings 28 of each of the helical gas conduits adjacent the outer face 24 are spaced sufficiently to leave intervening lands 29 roughly of a peripheral extent comparable to that of the various openings 28.

Also in accordance with the invention, the disc 23 in its outer face 24 is provided with a central conical depression 31 confined within the remaining central body 32 of the disc. This central body isvbounded by the inner surface 26 and a plurality of cylindrical surfaces 33 normal thereto.

Designed to interact with the disc 23 is a damper 36 mounted on the disc for relative rotation therewith. The mounting is accomplished by a bolt 37 axially disposed and held by a nut 38, the bolt serving as a fixed axle about which the damper 36 can be turned. Preferably, the frictional engagement between the damper and the disc is such that the damper can readily be turned to an adjusted position and can be clamped in place, if desired. The damper is of the general nature shown in elevation in Figure 7 and includes a number of wings 41 with intervening spaces so that the wings are eifective in one position of the damper to overlie the openings defined at the emergence of the helical gas conduits with the outer surface 24 and in another position substantially to overlie the lands 29 therebetween.

Means are provided for establishing and maintaining a maintenance or pilot flame despite wide variations in gas flow. For that reason, the conical central portion 42 of the damper is provided with a number of gas openings 43 and 44, all communicating with a circular groove 46 on the underside of the conical portion 42. The groove 46 is not only in continuous communication with the openings 43 and 44 but is likewise in continuous communication with a pair of bores 47 (Figure 5) extending through the disc 23 from the conical surface 31 tothe adjacent one of the cylindrical surfaces 33. In addition, as shown in Figure 6, bores 48 extend from the conical surface 31 of the disc 23 through the disc to emerge at the inner face 26 thereof.

There is achieved the efiect of a pressure channel provided by the bores 47 and the effect of a pitot tube probetween the gas jets towa'rdthe center of the burner. mixes not only with the gas on the outside of the gas vided by the bores 48. The net result of both of these effects resulting from the different locations of the bores 47 and 48 is to afford a more nearly uniform gas flow through the pilot openings 43 and 44 in the damper 36. Thus, while the pilot flame is centrally disposed and is available for ignition of the surrounding main flame, the pilot flame does not substantially vary either with the .position of the damper or with the quantity of gas flowing through the main burner.

In the operation of this device, the disc 23 and its associated damper 36 are preferably installed either in its elbow 16 or are installed in a coupling 51 (Figure 2) so that standard pipe elements can be utilized to construct the burner exactly to fit the desired performance. The disc 23 is screwed into the mounting member, such as the elbow'16 or the coupling 51, to any desired extent. As shown in Figure 3, the disc is virtually in outermost position, being locked there by a set screw 52. Under some conditions of operation, the disc 28 is screwed inwardly and occupies a position as far into the elbow or coupling as possible so that the surrounding part of the elbow or'coupling-serves as an annular shield. The diameter of the damper 36 is such that it is smaller than the disc and so readily enters into the then surrounding end of the mounting fitting.

When gas issues through the various helical passages, or conduits, 27, as well as through the pilot apertures, the gas, being given a swirling motion in the peripheral portion and emerging in jets from a plurality of spaced orifices as regulated by the position of the damper 36,

continues momentarily to swirl and to induce the flow of combustion air in through the spaces intervening Air rapid, turbulent, reasonably homogeneous intermixture of gas and air so that good, clean combustion and a short compact flame results. The quantity of flame is varied by the amount of gas which isfper'mitted to enter through the pipe 11 but the size of the pilot flame remains substantially'constantat its selected value so that even though 7 the main flame is variedwidely, the pilot flame always furnishes a substantially constant, minimum amount of combustion.

The arrangement in Figure 7 is generally as previously described but is augmented by an extra array of peripheral apertures 53 surrounding the helical passages 27 and themselves affording a second tier of helical gas jets for intermixture. Preferably, the direction of the helix for the apertures 53 is opposite to that of the helix for the openings 27. A large, well mixed, homogeneous flame results.

What is claimed is:

A swirl burner comprising a gas conduit having an axis, first threads provided on the interior surface of said gas conduit and extending for a predetermined distance inwardly from the end of said gas conduit, a disc of predetermined diameter, second threads on the periphery of said disc adapted to engage said first threads but extending for only a fraction of the axial distance of said first threads, means forming a plurality of helical gas conduits through said disc in the general direction of said axis, means forming a plurality of straight gas conduits extending in the general direction of said axis through said disc, a damper of less than said predetermined diameter'overlying said disc, means defining openings extending in the general direction of said axis through said damper, means for mounting said damper on said disc for rotation about said axis between a first conduits in all rotated positions of said damper relative to said disc.

References Cited'in the file of this patent UNITED STATES "PATENTS 1,840,453 Keith Ian. 12, 1932 FOREIGN PATENTS 188,684 Great Britain Nov. 17, 1922 424,663 Germany J an. 29, 1926

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