US1781784A - Gas burner - Google Patents

Description

Nov. 18, 1930. KERR 1,781,784

GAS BURNER Filed April 2, 1928 $513 N a 9 1: A pm Hi5 1 I m Patented Nov. 1 1930' UNITED STATES PATENT OFFICE HARRY E. KERR, OF CLEVELAND, OHIO, ASSIGNOR TO THE BARBER GAS BURNER COMPANY, OF CLEVELAND, OHIO, A CORPORATION OF OHIO GAS BURNER Application filed April 2, 1928. Serial No. 266,531.

My invention relates to gas burners, and my object in general is to provide an air and gas commingling jet or tube of relatively small dimensions which will produce a hori- ,zontally-spreading body of flame of relatively low height and of high British thermal unit value for use in water heaters having shallow combustion chambers or wherein a spreader, heatingelement or other device is 10 located closely adjacent the flame. The jet or tube can be used in .other appliances, for example, a single tube can be used in a coffee urn or percolator, but customarily a plural number of such jets or tubes are mounted at predetermined distances apart upon a gas distributing body or manifold which may be circular, straight,'0r of any. desired form dependent upon the heating appliance with which it is used. As designed and constructed the present jet or tube effects mixture of air and gas Within the tube, but this mixture is not combustible and will not ignite within the tube itself during operations, notwithstanding that the air ports in the base of the tube are open and unguarded and should a flame be directed into such ports and the interior of the tube. This desirable result is effected in part by the velocity of the gas stream, by permitting the gas to expand nat- 'urally and Without friction or resistance as it passes through the tube, and by promoting a free discharge of the mixture Without back ressure' from the upper end of the tube. ombustion occurs only in the open atmosphere surrounding the tube and in order that a flame of low height be produced the exits for the mixture are horizontally arranged, and in the present instance, a series of slots are used. 1

These-slots are horizontally-inclined relatively to the axis of the tube at different places radially thereof to provide a cupshaped and petal-shaped body of flame approximately three inches in diameter under normal gas pressure. The flame is light blue opposite the slotted exits and violetbeyond, and the production of this flame is accompanied Without objectionable noise or sound under the'highest gas pressure. 50 In the accompanying drawing Fig. i is a top view of a gas burner embodying my invention, and Fig. 2 a side elevation thereof. Fig. 3 is a sectional view of my improved burner jet or tube, and Fig. 4 a side view thereof with the spreader cone removed. Figs. 5 and 6 are transverse sections of the tube on lines 55 and 66, respectively, of Fig. 4. Figs? and 8 are side and bottom views, respectively, of the spreader cone. Fig. 9 is a perspective view of a complete burner jet or tube.

My invention involves the production of a simple and comparatively inexpensive tube A of relatively small dimensions, say-one and three-fourths of an inch long and approximately one-half of an inch in diameter. It is customarily made of hexagonal brass rod stock by screw-machine operations. One end is reduced and screw-threaded to permit attachment to a hollow gas distributing body or manifold B, shown in Fig. 2 as partly circular, a formcommonly used in water heaters of the storage or tank type. However, the showing is merely exemplary, as manifold B may be of any desired shape and size, anddany desired number of tubes A may be use The internal construction of tube A is of more importance, as slight variations in form or size affect the functioning ofthe device. Thus, the base or bottom end of the tube contains a gas orifice 2 of relatively small diameter and length. The diameter of this orifice varies dependent upon whether the burner is to be used for artificial or natural gas. To illustrate :Using artificial gas the orifice may be made with a #54 drill. and for natural gas it should be made with a drill. The entrance 3 in the screw-threaded extension 4 of the tube leading to orifice 2 is preferably of cup-shape. The remaining portion of the tube is drilled to varying diameters, a longitudinal bore 5 of approximately five-thirty seconds of an inch in diameter being formed in the enlarged hexagonal part 6 of the tube, and a flaring or tapering hole 7 being made which extends from this bore to a counter bore or chamber 8 of larger diameter in the upper end of the tube. Air intakes or cross ports 9 are drilled in the does not incline downwardly sides of hexagonal enlargement 6 which open into the bottom end of bore 5 opposite orifice 2, and I may use two or more such ports radially of the tube to entrain air into bore 5 from different directions. Chamber 8 may be eleven-thirty seconds of an inch in diameter and about three-eighths of an inch long, and it provides a slightly larger expansion chamber than the flaring end of hole 7. The direction of flow of the gas or mixture is changed when it reaches chamber 8 and it is caused to pass through a series of slotted exits 9 in the side walls of the tube. The gradual enlargement or taper of passage 7 from bore 5 upwardly permits the jet of gas to ex pand without friction or retardation after it leaves orifice 2 at high velocity, and the slightly larger chamber 8 permits still greater freedom for expansion and an immediate change of direction in flow. As an additional aid to a free'and full escape of the gas and whatever air is entrained with the,

gas the exits or slots 9 are made by sawing the circular wall of the tube downwardly at an angle from its upper end edge, and preferably at an angle of substantially thirty degrees to-the horizontal, the slots thereby extending circumferentially of the tube for a substantial distance. As shown, four such inclined slots are used equal distances apart, one in each segmental quarter of the tube through which the gaseous mixture is projected in a horizontally inclined plane, and thus four petal-shaped sheets of flame are produced which curl upwardly at their edges. It is desirable however, to have the flame of low height in certain heating appliances, and to spread the flame over a circular area. By sawing the wall of the tube at an inclination the walls of the narrow slot 9 so produced are also made to incline downwardly radially of the tube, thus projecting the gaseous mixture downwardly at the same inclination.

The saw cut extends on a straight line at an inclination through the end edge of the tube, but as the cut involves slotting of a quarter section of thecircular wall, the slot wall itself at the same angle throughout the length of the slot.

The minimium angle is at the beginning or at the upper edge of the tube and the maximum angle at the bottom end of the slot. Thus the gaseous mixture is projected downwardly at the greatest angle of inclination at the bottom end of the slot, and nearly in a horizontal plane, at the upper end of the slot.-

This is advantageous inasmuch as the upper end or beginning of one slot lies immediately above the lower end of another slot, and the separate mixtures are caused to issue in different angles on diverging lines, thereby being more free to mix separately with the air outside of the tube and to even overlap without affecting proper and perfect combustion.

To promote a substantial spread of the mixture and a wide expanse of flame as Well as a low flame, the tube is provided with a closure member C in the form of an inverted cone. Member C has a flat top of larger diameter than the tube itself so thatwhen it is seated upon the tube its edge portion will project as an annular flange 11 beyond the side wall of the tube and'serve as a flaring deflector for the mixture discharged circumferentially of the tube through all four slots 9.

The upper end of the tube projects into an annular groove 12 in the sloping surface of the cone, thereby firmly bracing and supporting the partially severed portions of the tube. The straight cylindrical inner wall 14: of groove 12 also provides a substantial backlng for the tube wall so that pressure may be applied at different places radially of flange llbto lock spreader member or cone C to the tn e.

The cone, including flange 11, serves to deflect the mixture and to spread it evenly in a plane below the flat top of the cap, seemingly preventing eddy currents from forming within the tube and even deflecting the mixture downwardly after it issues from the inclined circumferential slots 9. However, the body of flame is not deflected very much below the lower ends of the inclined slots, and a sudden down draft will not force the flame to a level with the air intake ports. However, should such drop of the flame occur the flame will not ignite the mixture in the tube, inasmuch as the tube is so dimensioned and constructed internally that a flame cannot exist within bore 5 under a normal gas pressure, nor will the tube back fire through slots 9. Complete closure of the top of the tube by the solid cone, including overhanging flange 11, also prevents dirt or foreign matter from dropping or finding its way into the tube and causing it to malfunction.

A tube constructed for "burning natural gas contains a smaller gas orifice but a larger bore and larger air port than a tube designed for artificial ,gas. The approximate proportions of a tube built for'burning natural gas is shown in Fig, 3, and in the orig; inal drawing as filed the tube is full size. In that connection it should be understood that if the same tube is enlarged, say twice the size, that it will not function in the same way as the smaller tube.

What I claim is 1. A gas burner, comprising a tube of relatively small dimensions having a gas orifice axially therein and an air port opposite said orifice, including an expanding passage ex tending into a mixing chamber having a closed outer end, communicating with circumdeflecting closure opposite the outer end of said bore. 1

3. A gas burner, comprising a tube having a gas orifice and air intake ports, including a tapered axial bore extending into an enlarged discharge chamber having slotted exits in the wall of said tube, and a conical deflector and clcsure member for the chambered end of said tu e.

4. A gas burner, comprising a tube of relatively small dimensions having a tapered longitudinal bore and a slotted side wall at one end of said bore, including a gas intake orifice axiali y of said bore and air intake ports open to said bore adjacent said gas orifice, and a combined closure member and deflector for the outer end of said bore-adjacent the slots in the side wall.

5. A gas burner, comprising a tube having inclined slots in its wall extending to one end thereof, and a closure member extending into the slotted end of the tube and supporting the severed portions of the tube, including air and gas intake openings in the opposite end of the tube.

6. A gas burner, comprising a tube having an axial gas orifice at one end communicating with a cylindrical bore of relatively small diameter and air intake ports in the side of the tube opening into said bore closely adjacent said gas orifice, said bore flaring to lar er dimensions and extending into a disc arge chamber in the opposite end of the tube, the side wall of said chamber being slotted circumferentially at an acute angular inclination to the axis of the tube, and the upper end of said chamber being closed.

7 A gas burner, comprising a tube having a conical spreader at one end and slots extending circumferentially of the tube obliquely across its curved wall, including separate gas and air intake openings at the opposite end of the tube.

8. A gas burner, comprising a tube having a tapered central passage, the smaller end thereof extending into a short cylindrical passage having a gas intake orifice and an air inlet port, and the larger end thereof comfice, and air ports adjacent said orifice, including an expanding passage, communicating with said orifice and extending into an enlarged chamber, having a relatively small intake for the air and gas, and the side Wall of said chamber having exit slots extending municating with an enlarged chamber having a side wall, including slots angularly inclined to the axis of said chamber and an end closure for said chamber extending into an annular deflecting flange adjacent the slots in said side wall, said flange being acute angularly related to said side wall.

9. A gas burner, comprising a tube of relatively small dimensions having a gas orifice and an air port, and an expanding bore of restricted area communicatlng and axially in line with said orifice, the top portion of the side wall of the tube itself having exits for the mixture, and the outer end of the tube being closed to deflect the mixture through said exits.

I 10. A burner tube having an axial gas ori

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