US2638976A - Gas burner cap with branched outlet ports - Google Patents

Description

May 19, 1953 F. VIXLER 7 GAS BURNER CAP wm-x TBRANCHED' OUTLET PORTS Filed Dec. 16, 1952 INVENTOR. 6505 V/XLEI? A rraezvsy parent during the course of the following disclosures.

In the drawings forming a part of this specification:

Fig. l is a perspective View of my burner head with its mixing tube;

Fig. 2 is a vertical sectional View through the head showing its connection to the upper portion of the mixing tube, the plane of the section being indicated by the line 22 of Fig. 3;

Fig. 3 is a top plan view of the burner head and adjacent portion of the mixing tube;

Fig. 4 is a bottom plan view of the burner head element removed from the supporting part being shown partly in section to illustrate the screen-retainingconstruction;

Fig. 5 is an elevation of the burner head showing a modified form of burner ports; and

Figs. 6 and '7 are enlarged diagrammatic views illustrating the outline of contour of the forms of burner ports shown in Figs. 1 and 5, respectively.

Standard designs of commercially available burners follow a general pattern of construction. For any given amount of gas to be utilized by an atmospheric type burner of multiple port construction, there must be a certain ratio of burner port area to the total air-gas mixture supplied in order to obtain satisfactory flame characteristics.

With the usual type burner the total port area that would be required to support 9,000 B. t. u. per hr. flames would be between .45 and .60 square inches. This total port area is obtained by the drilling of multiple small holes around the periphery of a burner cap. The diameter of such a burner will be around 3 inches, because about 40-56 holes will be required, each no greater than about .120" diameter and spaced no less than T15" apart.

If the port is too large, it will cause trouble. That is, the ignition velocity of the gas must be in correct ratio with the velocity of the gas issuing from the burner port, otherwise, if the ignition velocity is greater than the port velocity, the flame will tend to burn behind the burner port which is known to be quite objectionable. Thus, to avoid this objection, small port sizes, such as a 36 or 38 drill size or about .104" are used, and about 44 of these holes are required to pass the necessary amount of gas. All these and other requirements tend to keep the diameter of the burner at present large sizes.

It is also generally known that so-called secondary air supply at base of flame should be such that the boundary of the outer mantle of the flame is reasonably well defined and that no streaming occurs. In order to obtain this adequate supply of secondary air, the burner ports must be so spaced that one port does not interfere with or rob the next adjacent port of the required secondary air necessary for proper flame characteristics. This required port spacing adds still further to the diameter or circumference of the burner so that the optimum ratio of burner periphery to B. t. u. input per burner port is sacrificed to a lesser degree in my burner than in a conventional burner.

In the novel slot-like construction of my burner, it is noted that no part of the port slot aperture is wider than the diameter of the usual drilled hole found in contemporary burner design. Yet, the total port area of each aperture is equal to several regular drilled burner ports. As will be evident from analysis, higher primary air injection will be obtained from similar conditions of operation when a small number of large ports are used than when a relatively large number of smallerports giving the same total port area are employed, for the reason that the larger port has a higher discharge coefficient per unit of port areaand less resistance to flow.

The novel arrangement of my port construction also permits easy access of adequate secondary air to the entire perimeter of the specially shaped port or aperture for satisfactory flame characteristics. The design and construction of my burner does not follow the pattern of present known burner construction. Although the same ratio of actual total port area to the amount of B. t. u. per hour to be passed through the burner remains approximately the same as contemporary burners, my design requires only 13-14 burner ports to pass the same amount of gas. This is approximately one-third the number of ports as is required for present day burners. In using fewer burner ports, I am able to reduce the size of my burner head approximately one-half. This construction also lends itself to the manufacture by stamping thin metal, instead of using bulky and expensive cast iron and aluminum castings. This affords considerable saving in fabricating costs and greatly reduces the Weight.

The flame and operating characteristics of my burner are quite novel. When full gas rate is being emitted from the burner, the characteristic flame produced is quite long in comparison to the short flame produced by present day burners as used for the same purpose. The length of these flames is such that the flame pattern diameter, at the flame tips, approximates the size of the flame pattern diameter developed by the small flames of the larger diameter burners. Inasmuch as the same amount of gas is being consumed in both conditions, the same amount of heat is also supplied. However, my burner flames, being much longer and extending over a larger area of heating surface, will tend to scrub more area of the heating surface, thus adding to the overall efficiency. These flames being of elongatedform will tend to parallel the heating surface and thus can be placed closer to the utensil without direct flame impingement, thereby adding still further to the burner efficiency.

In the drawings, forming a part of this specification and showing an illustrative embodiment of this invention, the numeral I0 indicates my burner head of the general form of an inverted cup, preferably formed of thin sheet metal such as stainless steel or the like. The shape and conformation, among other advantages, lends itself to manufacture by stamping and punching operations.

The head member is shown as having a substantially flat top wall I2 a substantially vertical annular side wall portion I4; a flat horizontal outwardly extending flange l5, and a depending skirt IT. The side wall I4 is provided with an annular row of ports 20 extending from near the flange [5 to points near the plane of the top wall I2, and formed in the special port shapes, as will presently appear.

This head is adapted to be conveniently attached and detached from the mixing tube 25, which is shown as having an outwardly extending flat supporting flange member 26 rigid with the upwardly extending end of the mixing tube, and as having a downwardly offset portion within the skirt l1; and also as having outwardly extending arms 2 8 adapted to *engage a looking portion 30 of offset slots 31 formed in the skirt 4:1, and which convenient removal and bayonet locking action is provided for "holding the burner head onto the mixing tube member,

As :usual, the mixer tube is shown as having a horizontal portion and :a reduced Venturl zlDQItiOll 35 adjacent to the usual mixer which may be provided with an aircontrol 5 1th as a rota able sleeve iii serving as a mixer shutter. Any suitable air mixer control, of course, may be used. It may be noted, however, that the mixer tube is co pondingly f a v ry l ht construction which, taken with the extremely lightweight burner head construction, lends itself to the relatively light weight of, he ass mbl Within the wall M and extending around and across the burner ports 20, I may provide a cr en it whic may b hel in positi by a upwardly rned edge form d n a ofi e disk m mb r .42 hav a. po o fit ed ti h ly w thin the skirt H and then lying along the flange l5 and ext n in pwa n id the l wer ed e of the screen. This securing member may be held by a forced-fit, or by welding, or the like.

'A l hter p 45, mo e n t e bu r head '25, is c nnected to a fl h li er st ture no shown, for igniting the burner in a well known manner, the spacing of the individual ports 30 permitting ready travel of the flame from the lighter tube around the burner head.

One form of "my novel type of burner ports, by which the foregoing objects are attained, appears in Figs. 1, 2, and fi. These ports are in the form of a Greek cross. Proportions of the openings in this form, which have been found most satisfactory, are approximately as follows: The elongated slot-lik-e radiating portions 5'91 are approximately of an inch wide, while the overall dimensions between the ends 51 (see diagram, Fig. 6) are included in a dimension of about of an incl-1. The spacing between the individual port openings is preferably not less than the width of one of the elongatedopenings. openings of ports should be 3% of an inch or more to assure access "of secondary air 'to .the zone between the ports.

The height of the wall [4 of the burner head is preferably only slightly more than the height of the burner openings; whereby, it will be seen that the volume within the burner head; that is, between the top wall [2 and the supporting member 26, is very small in relation to that of burners of comparable capacity.

Instead of the Greek cross form, I have found that a comparably efficient type of port openings may be that of the Y form, shown in Figs. 5 and '7. Here, of course, are three elongated slot-like portions 52 radiating from a common open central portion, and the dimensions are such as to form a port of comparable area and approximately the same circumferential and vertical dimensions.

In each of these illustrative ports, it will be seen that the central open portion C, from which the elongated openings radiate, will form the central cone of the flame issuing from the port, and in which area the flow of gas is more free and thus more rapid than in the elongated radiating portions, there being a relative resistance or drag, in proportion to the volume, at the outer portions of the radiating slots. As indicated, in outlining the foregoing objects and in describing the operation and efiicicncy of my That is, the space between the adjacent 6 *bm ner za'bove, this coupled with the fact that-suchla port shape provides a relaytively largearea of-opening with relation to the edges of the sport defining its perimeter; and also athev fact that all portions of the flame are relatively thingattains the objective of assuring the easy access of secondary air to the flame as it issues f romthe port. I

'Iihe outwardlyrextending flange t5. forms a shield below the flames, preventing upward rush of air from tending to extinguish the flames at the ports, whiles'till permitting this free and efiicient access of the secondary air-to the flames as they issue from the ports. An effect of this construction is that the burner operates efficiently placed. only one-half of the usual distance from the bottom of the utensil.

I have found that with a burner head ,having :a diameter of approximately 1V2 incheal may provide is :to iii of the Greek .crjoss shaped or Y shaped ports closely arranged in a horizontal row, as shownand that such a burner will support com u tion atits normal fuel input of 9000 B- tu-v rer eu Furthe more, I have found that by the :special arrangement and construction of the burner head these novel events will maintain combustion efficiently at as'low ara'tie as 500 B. t. u. .per hour, 01' 1658-. highly desirablefor maintaining the simmering ranges of burning.

The. American Standard gas input rating for regular gas-range top burners is 9.000 B. tuu. per hour. larger size is referred to as a giant range top burner which will-produce 124000 B. t. u. per hour. I have found that by slightly 1110:0833: ing the diameter of the burner head, I may arrange. 1'7 ports of these novel shapes-in the circumference, and with desired spacing therebetween; and m y readily obtain this higher or maximum 1 2, 00 53.; 't. u. per hour rating. This same larger type may likewise 'be regulated to and burn efiiciently at a low input rating for simmering purposes.

With the dimensions given, it may be noted, for convenience and for thorough understanding of the design of my burner, that the total port area :in the burner head :of 1% inches diameter with 12 or :14: zponts, may preferably be between .40 and .60 square inch. The area of one Greek cross port opening, illustrated in Fig. 6; for example, is .028 square inch. The perimeter of this same port is one inch. The volume of the burner head within the space between the top I2 and the supporting plate 26 is approximately /4 of a cubic inch.

The relationships between the port areas, perimeter of individual ports, and circumference and volume of the burner head, which have been found to produce sufiicient results, and based upon these illustrtaive dimensions, with reasonable modifications thereof, are defined :in the appended claims.

Obviously, Various modifications may be made within the scope, intent, and teachings of the foregoing, while attaining the objects and requirements of given specified applications or uses.

Having thus described my invention, what I claim is:

1. A burner of the class described, comprising means for mixing gas and air and including a burner head forming a chamber communicating with said mixing means, and having a substantially imperforate top and a substantially vertically disposed side wall, said side wall having a series of separate outlet ports arranged around and extending through the periphery of said side wall, each port comprising three or more elongated narrow open portions radiating from a common central opening of substantially the width of said elongated portions, and in which each of the ports has a perimeter, the value of the numbers indicating its length in linear inches ranging from twenty to fifty times the value of the number indicating its area expressed in square inches.

2. The burner described in claim 1 in which the ports are separated a distance at least as great as the width of one of said elongated open portions.

3. The burner described in claim 1 in which an annular screen is disposed within the burner head, and extends across the openings of said ports on the inside thereof.

4. The burner described in claim 1 in which the shape of the burner ports is that of a Greek cross.

5. A burner of the class described, comprising means for mixing gas and air and including a burner head having a substantially vertical wall surface through which extend burner ports arranged in a horizontal zone around said wall and in Which each port is formed to comprise at least three slots radiating from a common central opening of substantially the width of said radiating slots, and the total area of the ports, expressed in a number indicating value in square inches, being approximately in the ratio of oneninth to one-fourteenth of the periphery of the burner head, expressed in a number indicating linear inches.

6. A burner of the class described comprising a means for mixing gas and air, and a burner head communicating with the mixing means, the burner head being formed to include a thin walled chamber having a substantially flat topand a bottom .wall spaced therefrom, and having an opening through which themixing means communicates, said burner head having an annular row of ports arranged around the burner head between the top and bottom walls, and each port being formed to comprise single openings including three or more elongated narrow portions extending from a common central open portion of substantially the same width as said narrow portions, the walls of the burner head including a volume which, expressed in a figure indicating cubic inches, has a relation to a figure indicating the periphery of the chamber expressed in linear inches in substantially the order of three-fourths cubic inch to between four and six linear inches.

7. A burner of the class described, comprising means for mixing gas and air, and a burner head communicating with the mixing means, the burner head being formed in the shape of a thin walled chamber having a substantially flat top, said burner head having an annular row of ports substantially parallel with the top, and each port being formed with three or more elongated narrow portions extending from a common central opening of substantially the width of said narrow portions, the burner head having an outwardly extending annular flange below and adjacent to the row of ports, the ports being separated, and the total area of said ports, expressed in a number indicating value in square inches, being approximately in the ratio of one-ninth to one-fourteenth of the periphery, expressed in a number indicating linear inches, and whereby as a result of the shape of the ports and the function of said flange a sufiicient supply of secondary air to the flame is provided to support eificient combustion while burning from simmering flame to the top 13. t. u. range of the burner.

LESLIE F. VIXLER.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 555,070 Billings Feb. 25, 1896 1,595,638 Beard Aug. 19, 1926 1,657,995 Garneau Jan. 31, 1928 2,015,266 Gerer Sept 24, 1935 2,190,099 Hahn Feb. 13, 1940 2,441,242 Harkins May 11, 1948 2,546,009 McGowan et a1 Mar. 20, 1951 FOREIGN PATENTS Number Country Date 526,476 Great Britain Sept. 19, 1940

Images