US2966211A - Gas burner - Google Patents

Description

GAS BURNER Earl J. Weber, Bay Village, Ohio, assignor to merican Gas Association, Incorporated, New York, N.Y., a corporation of New York Filed Apr. 15, 1958, Ser. No. 728,724

4 Claims. (Cl. 158-116) This invention relates to gas burners, especially those adapted for use las the top burner of a domestic gas range. While the gas burner provided by this invention is particularly intended for such use, it is also intended to be used whenever it may have useful application.

ln the past, top burners employed on domestic ranges have had inherent objections, among which are the following: (l) inability to provide a high turndown ratio without resort to complex structure; (2) the necessity of employing lan air shutter for primary air adjustment, which tends to get out of adjustment; (3) inability to operate satisfactorily on all city gases, including peak load gases; and (4) relatively low efficiency and high heat loss.

The present invention provides an improved gas burner which overcomes the above objections. More specifically, the present invention provides a burner with high turndown ratio, without -an air shutter, which is able to operate on wide ranges of gas types and pressure conditions at high efficiency and low heat loss.

The gas burner provided by this invention is principally characterized in that fuel gas or a gas-air mixture is supplied to each port outlet through a pair of mutually-impingent ow paths that lead to the port outlet, and the flow streams impinge on each other and produce a resultant at fan-like ow from the port, the at faces of which are at equal angles to the streams. This gives a arne pattern that makes for high eiciency and low heat loss and, furthermore, the burner has other advantages and overcomes the objections of prior gas burners.

The invention may be fully understood from the following detailed description with reference to the accompanyin g drawings whereinliig. l is an elevational vlew, partly in section, of a gas burner assembly employing a burner construction according to the present invention;

Fig. 2 is an enlarged vertical sectional view taken centrally through the burner;

Fig. 3 is a transverse sectional plan taken on the line 3-3 of Fig. 2;

Fig. 3a is an enlarged view of an area taken from Fig. 3 showing channel detail;

Fig. 4 is a similar view taken on the line 4-4 of Fig. 2; and

Fig. 5 is a schematic sectional plan view illustrating the flame pattern of the structure of Figs. 1 to 4.

Referring first to Figs. l to 5, there is shown a preferred form of a gas burner according to this invention..

In Fig. l the burner is designated generally by reference numeral 11 and is shown in association with a supply pipe 12, which is supplied with fuel gas by a pipe 13. Air enters the entrance end of pipe 12 and is mixed with the fuel gas in section 14. The present invention is not concerned with the type of fuel supply arrangement employed, that shown being merely for the purpose of illustration. It will be understood, therefore, that the gas burner may be employed in association with any supply arrangement.

Referring particularly to Figs. 2 to 5, the preferred nited States Patent form of the gas burner comprises a generally cylindrical burner head 15 having ports 16a in the form of vertically arranged slots equally spaced circumferentially of the head. In the illustrated embodiment, the burner head 15 is in the form of a generally cup-shaped member 1S, usually a casting, having an entrance opening 17 in the bottom thereof. The vertical slot ports 16a are formed by cutting vertical channels 16 in the wall of the cupshaped head 18 from the top edge to the cups bottom 19. An annular rib 20 extends inwardly from the sidewalls of cup-shaped head 18, from a position somewhat below the top edge of the sidewalls -to a point somewhat above the bottom 19. The channels 16 do not extend through the rib 20 but terminate at it in back wall 16h. A cap 21 lits over the upper edge of the sidewalls of head 18, and the depending flange or wall 22 of the cap extends below the top of rib 20. A ring 23 is xed around the lower part of the head 15 and extends above the lower edge of rib 20. Edges 22a and 23a of members 22 and 23, respectively, define the upper and lower ends, respectively, of ports 16a and are preferably knife edges but in any event are thin relative to the width of slot 16a.

The arrangement illustrated and described connes the flow of gas from the interior of head 18 into two oppositely directed impingement flow paths. rIhese paths result from flow both over and under rib 2@ to the channels 16. Thence because flanges 22 and 23 are made suliciently long to produce this directional effect, the fiow is directed down in the former and up in the latter case within each channel between the respective flanges and the outer surface of rib 20 which defines the bottom of the channel so that the bottom 1Gb and side walls 16e of the channel are continuous. in this way, mutually opposed streams of gas or air-gas mixtures are caused to impinge each other essentially head on, `and since at the point of impingement they are bounded on all sides (by rib 20, and burner channel 16 sidewalls 16C) but one, the gases tend to form a flat fan-shaped flow as clearly illustrated in Fig. 5 of the accompanying drawing, and hence upon ignition a flame of this shape, generally perpendicular to the oppositely directed flow paths and the slots. In other words the slot port 16a is the open side of the channel 16 Whose side walls 16C are everywhere spaced apart essentially the width of the slot so that impingement must take place at the slot port level. Since the channels 16 are vertically arranged, the flame is hon'- zontal and one ame may be arranged to overlap another. However, being horizontally directed, the flames do not tend to impinge a pan on the burner directly.

It will be observed that the edges of encircling walls 22 and 23 which define part of the orifice of each of the burner ports 16a are beveled to form knife edges, as indicated at 22a and 23a, respectively. The vertical lateral edges of the orifice are defined by channel side walls 16C of channels 16. This arrangement has the effect of permitting the opposed streams to impinge one another at or just below the actual orifice opening so that the bounding channel side walls 16C will not interfere with the fan-shaped gas distribution created thereby and clearly illustrated in Fig. 5. For optimum fanning, the provision of the knife edge 22a and 23a which define the upper and lower ends, respectively, of the orifice at which the opposed streams originate, is the most desirable construction, although satisfactory results are obtained by a thin edge in the order of 3/32" for a one inch orifice. The shape of the orifice and its dimensions are not, however, determinative of the effect which is enhanced merely by the effect of wall thinness in the regions from which flow the impinging streams.

In order to provide a high turndown ratio and to enable operation of the burner at a low input rate (e.g.

about 350 B.t.u. per hour) suitable for keep-warm and simmer operations, the number of channels 16 is much smaller than the number of ports ordinarily employed. Thus, in the illustrated embodiment only eight ports are provided. However, the port Varea provided by such a small number of ports is not, in itself, su'icient to proper ly support the combustion of fuel gases, such as natural gas, at a full input rate of 9,000 B.t.u. per hour or higher. Consequently, with the input rate at or about full rate, the ames would lift off of the ports if there were no provision to prevent this. To provide for proper combustion of the fuel gas or gas-air mixture at high input rates, and to prevent lifting of the flames, auxiliary ports 24 are provided in the lower part of the burner head 15, and these ports feed fuel gas or gas-air mixture into an annular space 25 which leads to an annular outlet 26 that is directed upwardly just below the level of the main ports 16a. At high inputs, the fuel gas or gas-air mixture emitted through the annular outlet 26 burns in an annular flame which serves to prevent lifting of the frames at the main ports.

Conveniently, the lower portion of the burner head is formed as illustrated to seat within the upper end of a tubular member 27 which has horizontal and vertical annular anges 28 and 29, respectively, to form the annular flow space for channel 25 in cooperation with the adjacent portions of the burner head. By having a friction t between the burner head and the member 27, the burner head may be readily removed for cleaning purposes. Also, in the arrangement shown, the member 27 is in the form of a collar which fits over the tubular portion 30 at the upper end of the supply pipe 12 and seats on an enlargement or ange 31 provided on the pipe 12.

In a specic embodiment of the gas burner shown in Figs. 1 to 5, the burner head 15 has an outside diameter of 1% inches, an outside depth of the cup-shaped portion of inch, an inside depth of 1/2 inch, and a wall thick ness at the central portion of 1A inch. The upper and lower undercuts forming ange 20 are 1A; inch by I; inch. The eight vertical channels 16 are formed by making equally spaced saw cuts TA6 inch wide.

The present application is a continuation-impart of my application Serial No. 448,002, filed August 5, 1954, and entitled Gas Burner, which application Serial No. 448,002 has become and now stands, abandoned.

I claim:

1. A gas burner adapted to be connected to a source 4' of gas supply, comprising a cylindrical burner head, an outward facing surface means forming a plurality of channels having their long axes vertically oriented, their open sides facing radially outward and their side walls terminating in the outward facing surface, the open sides ofthe channels providing ports arranged circumferentially around the head parallel to the cylindrical axis, the front edges of the side walls of said channels dening the longitudinal edges of the ports and the side walls being spaced apart a distance behind the ports essentially the width of the ponts and a back wall opposite each port and continuous with the side Walls, and means covering the open sides of the channels at the ends of the channels and delining the ends of the ports and having thickness approaching knife-edge thickness at the edges of said ports, said means serving to direct gas ow in the channels from opposite directions whereby the streams of gas ow in said channels are caused to impinge on each other and if of sucient velocity produce a resultant flat horizontally dsposedffan-shaped ow of gas outwardly from the ports, each flow pattern issuing from said ports having its flat sides at approximately equal angles at the longitudiy A nal axis of the slot ports.

2. The burner of claim l in which the means covering the open sides of the channel at each end are terminated at the channel in knife edges.

3. The burner of claim 2 in which the channels are all cut n a common cylindrical surface of the burner head so that they lie parallel to the axis of the cylinder and a pair of continuous bands are provided at each end of the cylinder so that cach provides the means covering the open sides at one end of rall the channels.

4. The burner of claim 3 in which the burner head portion providing the cylindrical surface is a ring and one band is the rim of a cap which covers the open sides of the channels at one end of all the channels and the other band closes the other end of all the channels in the ring.

References Cited in the ile of this patent UNITED STATES PATENTS 672,748 Allen Apr. 23, ll 2,591,263 James et al. Apr. Il, l952 FOREIGN PATENTS 615,805 Great Britain a lan. l2, 1949 654,687 Great Britain Apr. 8, 1S49 www.

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