US2875821A

US2875821A - Sheet metal burner and cross lighter

Info

Publication number: US2875821A
Application number: US467731A
Authority: US
Inventors: George W Allen
Original assignee: Stewart Warner Corp
Current assignee: Stewart Warner Corp
Priority date: 1954-11-09
Filing date: 1954-11-09
Publication date: 1959-03-03
Anticipated expiration: 1976-03-03

Description

March 3, 1959 w. ALLEN swam METAL BURNER AND CROSS LIGHTER 2 Sheets-Sheet 1 Filed Nov. 9, 1954 Ma. rh 3, 1959' a. w. ALLEN SHEET METAL BURNER AND CROSS LIGHTER 2 Sheets-Sheet 2 Filed NOV. 9, 1954 United States Patent O SHEET METAL BURNER AND CROSS LIGHTER George W. Allen, Indianapolis, Ind., assignor to Stewart- Warner Corporation, Chicago, Ill., a corporation of Virginia Application November 9, 1954, Serial No. 467,731

3 Claims. (-Cl. 158115) The present invention relates to gas burners adapted to be mounted alongside each other.

One object of the invention is to provide an improved gas burner adapted to be used alongside similar burners and having highly efficient means for vcross lighting between burners.

A further and more specific object is to provide an improved gas burner of the above character which is well suited for economical fabrication from sheet metal.

Other objects and advantages will become apparent from the following description of the form of the invention illustrated in the drawings, in which:

Figure 1 is a plan view of a burner embodying the invention;

'Fig. 2 is a side view of the burner of Fig. 1;

Fig. 3 is a right end view of two burners mounted side by side;

Fig. 4 is a fragmentary plan view on an enlarged scale of one cross-lighting runner; and

Fig. 5 is a fragmentary vertical view on an enlarged scale of a cross-lighting runner as viewed from the outer end.

The gas burner incorporating the invention is adapted to be mounted side by side with similar burners, Fig. 3, in a heater or furnace (not shown) to providethe heating capacity desired. Each burner is symmetrical about a vertical longitudinal plane and is relatively narrow in relation to its length.

A long narrow series of burner openings extending along the top of the burner, Figs. 1 and 2, are fed with a mixture of gas and air from a horizontally elongated plenum chamber 12 underlying the openings. The plenum chamber 12 is widened generally from top to bottom and deepened from its outer ends toward the center. The lower central portion of the chamber merges with the upper end of a short vertical passageway 14 connected with the inner end of a horizontal fuel mixing tube 16. Shaped and dimensioned in accordance with conven-.

tional burner design practice, the mixing tube 16 has a circular transverse configuration which sharply decreases in diameter from the outer end 20 of the tube to a venturi throat 18 and then progressively increases in diameter to the inner end of the tube which merges with the passageway 14.

The mixing tube 16, the plenum chamber 12 and the connecting passageway 14 are fashioned in a very economical manner from two generally vertical sheet metal plates 22, 24 formed substantially as mirror images of each other. Both plates are blanked to have a generally rectangular shape, the upper right and the lower left corners of each plate being cut away, as shown in Fig. 2.

Each plate 22, 24 is shaped by suitable dies or the like to form an elongated bulge 26 therein extending horizontally inward from the lower right corner of the plate, Fig. 2, in spaced relation to the lower marginal edge of the plate. Each bulge 26 is displaced away from the opposed plate and shaped to form a one-half section of the mixing tube 16. The inner end of the bulge 26 in each 2,375,821 Patented Mar. 3, 1959 ice plate merges with an upwardly extending bulge 28 shaped to form' a half section of the passageway 14; The upper end of the bulge 28 merges with a much larger bulge 30, which fans out horizontally in both directions and extends to the upper edge of the plate to'forrn a half section of the plenum chamber 12. The upper edge of each plate 22, 24 extends horizontally a short distance beyond the opposite extremes of the plenum chamber bulge 30 in theplate. v

The two plates 22, 24 are fastened in face .to face engagement by suitable spot and

seam welds

32 and 34 forming gastight seals between the plates running along opposite sides of the mixing tube 16, the passageway 14, and the plenum chamber 12. I

As shown in Figs. 1 and 2, the uppermarginal edge of each plate 22, 24 above the plenum chamber bulge 30 in the plate is olfset horizontally outward from the opposite plate to form one straight vertical side 38 of a long narrow burner opening channel 40. The extreme upper edges of the flat channel sides 38 are curled outwardly and downwardly to form reinforcing beads 41.

The flat channel sides 38 are positively held in spaced relation to each other by four transverse members 44 spaced horizontally along the channel 40 just below the channel sides and attached at opposite ends to four I downwardly extending flats 46 on each plate 22, 24.

' burners, Fig. 3.

vertically disposed

sheet metal stampings

58, 60 shaped The members 44 also support a plurality of vertically corrugated ribbons 49 fitted into. the channel 40 with flat spacer ribbons 50 between each corrugated ribbon to form the burner openings 10. The ribbons 49 and 50 are secured in place by two transverse clips 51 snapped over the beads 41 at opposite ends of the channel 40.

Short opposed end sections 52 of the plenum chamber bulges 30 at the mixing tube end of the channel 40 are flattened to extend straight down from the flat channel sides 38. A central aperture 54 is formed in each end flat 52. p

The apertured flats 52 form support bases for horizontally elongated cantilever lighters or runners 56 brazed to the flats and projecting laterally toward adjacent Each runner 56 is formed from two as mirror images of each other, except for certain structural features to be presently described. Each stamping has a generally flat marginal edge 62 of U-shape configuration extending around the stamping from points on the adjacent flat 52 above and below the aperture 54 in the flat. A central, horizontally elongated bulge 64 in each

stamping

58, 60 is offset outwardly from the opposed stamping and extends from the adjacent support flat 52 to the U-shaped marginal edge 62 of the stamping. The bulges 64 in the two stampings of each runner 56 form a passageway within the runner which communicates with the interior of the plenum chamber 12 through the adjacent aperture-54, which is almost entirely encircled by the runner.

The upper edges of the runners 56 adjacent the plenum chamber 12 are substantially flush with the upper edges of the burner ribbons 49, 50. 'Outwardly from the plenum chamber 12, the upper edge of each runner 56 curves downwardly with a progressively increasing curvature to the extreme end of the runner.

The lower portions 65 of the opposed marginal edges 62 of the two stampings'SS, 60 of each runner 56are seam welded together up to a horizontal offset line 66' (see Figs. 3 to 5) extending through the extreme outer stream of fuel mixture extending from the burner openings to the outer end of the runner from which the fuel mixture is directed horizontally (just above the offset line 66) toward a similar runner on the adjacent burner (see Fig. 3). Inthis' manner the runners 56 of adjacent burnersprovide a substantially continuous stream of fuel mixture extending" from burner to burner for efficient, dependable cross-lighting between burners.

To provide further assurance of unfailing cross lighting between burners when the gas pressure is extremely low, an auxiliary channel 71 is swaged rearwardly in the upper marginal edge 62 of the rear stamping 60 of each cross lighter 56 to extend outwardly at a somewhat upwardly inclined angle from the outer end of the central bulge 64 in the stamping to the extreme outer edge of the lighter gap 70. The cross lighter channels 71 increase the flow of gas horizontally from the lighters of adjacent burners as a further aid to the progress of flame from lighter to lighter.

In the event that the gas outlet gap 70 of one or more of the burner cross lighters 56 should become blocked by falling scale or otherwise (a most unlikely condition) effective cross lighting between burners is effected by gas supplied through a row of auxiliary lightin'g ports 73 drilled in the front stamping 58 of each lighter 56 and extending generally from the outer end of the lighter to the plenum chamber 12.

Fuel gas is supplied to each burner through a conventional nozzle (not shown) fitted into a support 72 extending across the outer end of the mixing tube 16.

'Formed almost entirely of sheet metal, the improved burner is, extremely economical to manufacture. The

[sheet metal construction is inherently resistant to breakage. Moreover, the two plates 22, 24 form strong reinforcing webs 74, 76 between opposite ends of the plenum chamber 12 and the mixing tube 16 (Fig. 2). These webs can be used in mounting the burner.

While I have shown and described a preferred embodiinerit ofmy inve'ntion, it will be apparent that varia- -tions and modifications thereof may be made without departing from the principles and scope of the invention as set out in the following claims.

I claim:

1. A sheet metal gas burner adapted to be used alongside another burner and comprising, in combination, twoopposed generally vertical plates of sheet metal formed substantially as mirror images of. each other, each plate having an elongated bulge therein displaced outwardly from the opposed plate and shaped to form a half section of a fuel mixing tube, said mixing tube bulge of each plate merging with an enlarged bulge reaching to the upper edge of the plate and shaped to form a half section of a. plenum chamber, a large section of the upper marginal edge of each plate being offset from theopposed marginal edge of the opposite plate, said .plates b'eing welded in face to face engagement with each other, means coacting with-said oflEset marginal edges of the two plates to define burner outlets from the space-betweensaid plenum chamber bulges of the 'two plates, the plenum chamber bulge of at least one of said plates defining an aperture therein, a cantilever lighterof sheet metal attached at one end to said one plate in embracing relation to said aperture therein, said lighter comprising two sheet metal stampings attached respectively at one end to said one plate on opposite sides of said (aperture therein, each stamping having a U-shaped marginal edge bounding the stamping generally in a substantially vertical plane as the stamping projects away from the adjoining plate, the central portion of at least one stamping extending from the end thereof adjacentsaid aperture to said U-shaped marginal edge of the stamping being bentoutwardly from the opposed portion of the other stamping to form therewith an internal'lighter cavity communicating through said aperture with the plenum chamber, that part of the one stamping central portion which delimits the upper extremity of the cavity turning outwardly from the plenum chamber and downwardly at a progressively increasing slope, the opposed portions of the U-shaped marginal edges of the two stampings extending from the adjoined plate along the underside of the lighter to the projecting end thereof and up to a generally horizontal line running through the projecting end of the lighter being sealed together, the upper portions of said marginal edges of the two stampings above said line curving outwardly from said adjoined plate and downwardly to the projecting end of the lighter with a progressively increasing slope, said upper portions of said marginal edges of the two stampings above the line being offset horizontally from each other down to the line to define a thin crosslighting fuel gap communicating with said internal lighter cavity and opening upwardly and horizontally outwardly therefrom to issue fuel from said cavity upwardly from the lighter and horizontally outward from the projecting end thereof, a portion of said marginal edge of at least one of said lighter stampings disposed at the projecting end of the lighter above said line being swaged away from the opposing portion of the marginal edge of the other stamping to have a spacing therefrom greater than the width of said cross-lighting gap to provide for an increased flow of fuel from said internal lighter cavity horizontally outward from the projecting end of said lighter, and one of said stampings defining a plurality of auxiliary gas outlet apertures therein communicating withsaid internal lighter cavity and disposed adjacent its upper marginal edge in a series extending substantially from said plenum chamber means to the projecting ,end of said lighter.

'2. In a combination heater construction of the type in which a plurality of gas burners are disposed adjacent each other and in which a mixing tube integral with each of the burners causes air and gas to be mixed in. proper proportions and to be directed to a plenum chamber means from which the gas is emitted through burner ports for ignition, the combination with each of the burners of a cross lighter construction which permits limited variable spacing and misalignment between the burners comprising a pair of sheet metal stampings in engagement with each other, fixed at one end of the respective plenum chamber means, and extending toward an adjacent burner, the central portion of at least one stamping being bent outwardly from the opposed portion of the other stamping to form therewith an internal cavity in the lighter, that part of said central portion which delimits the upper extremity of the cavity extending outwardly from the plenum chamber means and downwardly at a progressively increasing slope, passageway means connecting the cavity with the plenum chamber, the lower edges of the two stampings beingsealed together from the plenum chamber means toa'Qcentral. generally horizontal linerin their outer ends, the tuppernmarginal :edges of the two stampings turning outwardly from said plenum chamber and downwardly toward the projecting end of the lighter to said line at a progressively increasing slope, said upper edges being narrowly spaced from each other to define a thin cross lighting fuel gap communicating with the lighter cavity and opening upwardly and horizontally outwardly there from to issue ,fuel from said cavity upwardly from the lighter and horizontally outwardly from the projecting endthereof, and one .of said stampings defining adjacent its-upper edge a plurality of auxiliary gas outlet apertures arranged in a seriesextending substantially from said ,plenumphamber means to the horizontal line.

3. In a combustion heater construction of the type in which a plurality of gas burners are disposed adjacent each other'andin which a mixing tube integral with each of the burners causes air and gas to be mixed in properproportions and, to be directed to a plenum burner ports for ignition, the combination with each of the burners of a cross lighter construction which permits limited variable spacing and misalignment between the burners comprising a pair of sheet metal stampings in engagement with each other, fixed at one end of the respective plenum chamber means, and extending toward an adjacent burner, the central portion of at least one stamping being bent outwardly from the opposed portion of the other stamping to form therewith an internal cavity in the lighter, that part of said central portion which delimits the upper extremity of the cavity extending outwardly from the plenum chamber means and downwardly at a progressively increasing slope, passageway means connecting the cavity with the plenum chamber, the lower edges of the two stampings being sealed together from the plenum chamber means to a central generally horizontal line in their outer ends, the upper marginal edges of the .two stampings turning outwardly from said plenum chamber and downwardly toward the projecting end of the lighter to said line at a progressively increasing slope, said upper edges being narrowly spaced from each other to define a thin cross lighting fuel gap communicating with the lighter cavity and opening upwardly and horizontally outwardly therefrom to issue fuel from said cavity upwardly from the lighter and horizontally outwardly from the projecting end thereof, and the edge of at least one of the stampings being bent outwardly from the opposed portion of the other stamping adjacent the horizontal line to define an auxiliary gas outlet channel communicating with the cavity and inclined upwardly and outwardly toward an adjacent burner.

References Cited in the file of this patent UNITED STATES PATENTS 709,356 Piper Sept. 16, 1902 1,161,438 Bell Nov. 23, 1915 1,289,555 Schall et a1. Dec. 31, 1918 2,470,880 Zimbelman et a1. May 24, 1949 2,541,428 Leo et al Feb. 13, 1951 2,560,777 Reeves July 17, 1951 2,658,504 Jaye et al. Nov. 10, 1953 2,658,569 Hughes et al Nov. 10, 1953