US2398611A

US2398611A - Igniting means for burners

Info

Publication number: US2398611A
Authority: US
Publication date: 1946-04-16
Anticipated expiration: 1963-04-16

Description

pria w, 1946. D. BEGGS 27,398,611

Y IGNITING MEANS. FOR BURNERS l Filed April-1, 1941 v Z Smaentor Qqgy @wim Gttorneg Patented Apr. 16, 1946 UNITED STATE.

s Partitur oFFice IGNITING MEANS ron. BURNERS Don Beggs, Toledo, Ohio, assignor, by mesne` assignments, to Surface Combustion Corporation, Toledo, Ohio, a corporation of Ohio Application April 1, 1941, Serial No. 386,236 i 7 Claims. (Cl. 126-91) This invention relates to improvements in heating apparatus of the type wherein fuel gas and combustion-supported air are delivered to a combustion chamber in separate but contiguous streams in order to obtain delayed combustion. One example of such apparatus is shown in patent to Hepburn et al., No. 2,047,471, wherein the combustion chamber is atube adapted to be used as a heating element; in furnace chambers and the like. It will also be noted that in this patent the means for igniting the gas comprises a premix burner around the discharge end of the fuel supnomenon in the following way: Referring to Figs. 2 and 3, IS indicates a relatively small baille in the form of `a radially extending'iinger at one end of a rod Il positioned in the air passage I5, the linger being relatively close to the discharge end of the gas discharge tube I4. Due to the zone of reduced pressure at the downstream side ply tube. The object of the present invention is to provide a simple and practical improvement in means for providing a pilot flame for a firing system of the type disclosed in said patent. Other objects will appear as the description proceeds.

-In the accompanying drawing wherein the preferred form of the invention is disclosed- Fig. 1 illustrates the type of heating apparatus with which the invention has special utility; namely, heating apparatus, embodying an internally 'red tube for use as a heating element in furnace chambers and the like.

A Fig. 7 is a cross sectionA on line 'I-l of Fig. 6,l for the purpose of illustrating the application of the modification shown in Fig. 4.

In Fig. 1, Iindicates a furnace chamber wall and I I a heating tube which extends into and out of said chamber through said Wall. At one end of said tube is a suction producing device I2 for producing draft through the tube.` Projecting into the other end of the tube to a point some distance inwardly from the air intake end' I3 thereof is a fuel supply tube or conduit I4, it

being understood that the air. for supporting combustion of the fuel enters the tube I I through the annular flow passage I5 about the gas supply conduit.

The present invention is predicated on the phenomenon that a zone of reduced pressure or partial vacuum tends to occur at the down stream side' of a non-streamline body placed in the path of ow of a stream of air or other gas, In the present invention I take advantage of this phe- 65 tion Wall for delivering separate streams 0i'.y fuel of this iinger or baille I6 some of the gas flowing 'from the tube I4 will tend to flow toward the' zone of reduced pressure and in so doing will become mixed with the air.` This mixture on heiligl ignited will form a pilot flame at the `end of the Y fuel tube I4 in igniting proximity Vto the Point where the main air and gas streams meet as will now be readily understood.

Other relatively small bailles I8 may extend rafdially outward from the tube I4 itself to provide a plurality of pilot flames around the tube. The primary reason for utilizing a rod I1 for sup# porting the baille I6 is to permit the latter to be utilized as a spark electrode for igniting the mixture produced therebehind as said-it being` 1inderstood that the rod I'I is connected to a suitable source of electric power (not shown). .It'

will also be understood that once the air-gas mixtures behind the bailies I6 and I 8 have been ignited the resulting pilot flames will tend to persist Vas long as both air and fuel gas flow into the radiator tube I I.

In Fig. 4, the arrangement is the .same as in Fig. 2 except that I 'provide a relatively small gas port I9 in the wall' of the gas tube at the downstream side of the baille I8 for the more direct flow of the gas from the tube to the zone of reduced pressure.

In Figs. 5 and?, I have shown how the inven tion may be applied to a modified form of burner adapted to fire into a furnace 2I| such as a forgefurnace. The gas passage is indicated at 2I and the air passage at 22, the two passages being separated by a partition wall 23. The primed numerals indicate parts similar to those indicated by the same but non-primed numerals in the other figures and the mode of operation will be readily understood from what has already been said.

From the foregoing description it can bereadyily seen that the present invention provides a gas and air to a combustion space. of means for turbulently intermixing relatively small quantities of said streams to produce a premix pilot name at the end of said wall. said means comprising a relatively small baffle positioned in the air passage to cause a turbulent partial vacuum to be produced thereinbehind the baille, said baille being positioned in such close proximity tube having at its exhaust end a suction producing device so thatcombustion-supporting air and fuel gas introduced into the tube at the front tothe end of said wall that the said partial vacuum will be effective to divert towards itself from a spark gap therebetween for igniting the airgas mixture produced as said. l

2. Th'e combination with an air passage and a gas passage separated from each other by a partition`wal1 for delivering separate streams of air and fuel gas to a combustion space, of means for producing a premix pilot flame in relatively close proximity to the downstream terminal of ysaid wall for igniting the air and gas issuing from said passages, said means comprising a relatively small baiile in one of said passages in relatively close proximity to the downstream terminal of said wall for producing adjacent said terminal a turbulent partial vacuum to produce the air-gas mixture that maintains saidpremix ame, said baiile being spaced from said wall to provide a spark gap therebetween for igniting said mixture.

-end thereof will tend to Vbe drawn through the tube, a gas conducting tube projecting 4centrally into the front end of the combustion tube to discharge fuel gas centrally thereinto and to form vbetween the tubes an annular .passage for the inicoming air, and means for producing within the combustion tube a premix pilot flame forigniting the fuel gas issuing from the said gas conducting tube, said means comprising a radially extending finger in the air passage in relatively close proximity to the discharge end of said gas conducting tube to produce behind the nger a turbulent partial vacuum eiectiveto divert towards itself from the stream of gas from the gas conducting tube enough gas to produce behind the finger a zone of combustible mixture sumcient to maintain 'said pilot name at said zone.

6.`In combination, a relatively long combustion tube having at its exhaust end a suction producing device so that combustion-supporting air and 3. The combination with an air passage and a l gas passage separated from each other by a parti- I tion wall for delivering separate streams of air and fuel gas to a combustion space, of means for producing. a premix pilot ame in relatively close proximity to the downstream `terminal of said wall for igniting the air and gas issuing from said passages, said means comprising a relatively small baille in the air passage in relatively close proximity to the downstream terminal of said wall for producing adjacent said terminal a tur l 5 bulent partia'l 1vacuum which will be effective to divert towards itself from th'e main gas stream enoughy gas to produce the air-gas mixture that maintains said pilot flame, said wall being apertured in relatively close proximity to said baille l at the downstream side of the latter for the flow of gas through said wall.

4. In combination, a relatively long combustion tube which at its intake end has an air entering passage and a gas entering passage separated from each other by a. partition wall so that'the air and gas will initially enter the tube as separate straight away streams and which' tube at its exhaust endhas a suction devicefor producing a draft through thetube, and means for producing a premix pilotlame in the tubefor igniting the gas where it first comes in contact with air after leaving the gas passage comprising `a relatively small baille in the air passage in rela# tively close proximity to the downstream terminal of said wall for producing behind said baille a turbulent partial vacuum effective to divert towards itself from the main gas .stream enough gas to produce the air-gas mixture that maintains said pilot flame.

v5. In combination, "a relatively long combustion fuel gas introduced into the tube at the front end thereof will tend to be drawn through the tube, a. gas conducting tube projecting centrally into the front end of the combustion tube to discharge fuel gas centrallythereinto and tovform between the tubes an annular passage for the incoming air, and means for producing within the combustion tube a premix pilot ilame for igniting the. fuel gas issuing from Athe said gas conducting tube, said means comprising a radially extending finger in the air passage in relatively close proximity to the discharge end of said gas conducting. tube to produce behind the finger a turbulent partial vacuum effective to divert towards itself from the stream of gas from the gas conducting tube enough' gas to produce behind the finger a zone of combustible mixture suflicient to main-` tain said pilot flame at said zone, the said finger being radially spaced from the gas conducting tube to form a spark gap therebetween for igniting said mixture.-

7. In combination, a relatively long combustion tube having at its exhaust end a suction producing device so that combustion-supporting air and fuel gas introduced into the tube at the front. end thereof will tend to be drawn through the tube, a gas conducting tube projecting centrally into the front end of the combustion tube to discharge fuel gas centrally thereinto and to form between the tubes an annular passage for the incoming air, and means for producing within the combustion tube a plurality of premix pilot names each l adapted to ignite the fuel gas issuing from the gas conducting tube, said means comprising a. circumferential row of radially-extending ngers in the air passage in relatively close proximity to the discharge en d of the gas conducting tube to -ing tube enough gas to form behind euch nger a zone of combustible mixture sufcient to maintain a pilot iiame at said zone.

f DON Bacuis.