US3825402A

US3825402A - Gas burner

Info

Publication number: US3825402A
Application number: US00307078A
Authority: US
Inventors: D Duperow; W Ferlin
Original assignee: Lincoln Brass Works Inc
Current assignee: Lincoln Brass Works Inc
Priority date: 1972-11-16
Filing date: 1972-11-16
Publication date: 1974-07-23
Anticipated expiration: 1991-07-23

Abstract

Closed-center inverted cup type gas burner has noncircular, nonlinear slot-shaped burner ports with uniform widths, the port axes being angled upwardly to clear the top of a surrounding aeration pan. The fuel valve orifice is metered to inject gas into the mixing tube at velocities inverse to the flow rate to the burner.

Description

United States Patent [191 Duperow et al.

[111 3,825,402 51 July,23, 1974 GAS BURNER Inventors: Donald E. Duperow; William J.

Ferlin, both of Detroit, Mich.

Assignee: Lincoln Brass Works, Inc., Detroit,

Mich.

Filed: Nov. 16, 1972 Appl. No.: 307,078

US. Cl. 239/568, 239/601 Int. Cl B05b 1/14 Field of Search 126/39 11, 39 N, 39 K;

References Cited UNITED STATES PATENTS 8/1953 Schlenk et a1. 126/39 K 2/1957 Kindl 126/39 N X l/1967 Stohrer, Jr. et a1 239/567 3,738,577 6/1973 Blanzy et al. 239/601 FOREIGN PATENTS OR APPLICATIONS 105,608 11/1938 Australia ..239/567v Primary ExaminerCarroll B. Dority, Jr. Assistant Examiner-I-Iarold Joyce Attorney, Agent, or FirmBames, Kisselle, Raisch &

Choate [5 7 ABSTRACT Closed-center inverted cup type gas burner has noncircular, nonlinear slot-shaped burner ports with uniform widths, the port axes being angled upwardly to clear the top of a surrounding aeration pan. The fuel valve orifice is metered to inject gas into the mixing tube at velocities inverse to the flow rate to the burner.

13 Claims, 4 Drawing Figures GAS BURNER an inverted closed-center cup whose end wall forms the top of the burner and whose side wall adjacent the top is provided with an annular array of burner ports. Such,

burnerscharacteristically have a maximum output of 6,000 BTU.

Because of their simplicity, low cost, compactness and attractive appearance it would be desirable to use such burners in full size domestic gas ranges. However, these ranges must have burners capable of an output of about 12,000 BTU. No. conventional burner of the type under consideration has such a capacity since its port area is too limited. Moreover, when such a burner is modified to provide the necessary port area for I2,000 BTU operation, it does not furnish gas properly at low turn down because of improper fuel gas-air mixture.

In the typical domestic gas range, a pan is mounted around the burner, this pan frequently being referred to as a drip pan or aeration pan. Portions of the pan proximal to the burner are below the level of the burner ports while distal portions of the burner dish upwardly so that the pan forms a well in which gas tends to accumulate when the burner is turned on but prior to ignition. When ignition occurs, the entire body of the accumulated gas ignites with an unpleasant thump or puff.

A principle object of the present invention is to provide a relatively simple, inexpensive burner structure improved in that while it is compact and attractive in appearance it has increased port area for operation at high output and which nevertheless operates efficiently at low turn down. Another object of the invention is to provide'a burner structure improved so that gas issuing from the burner ports prior to ignition does not collect in the surrounding aeration pan thereby avoiding puff type ignition.

In general, the invention is carried out by forming each burner port asan elongate, nonlinear slot having angled leg portions interconnected at their lower ends by a return portion. The slot has substantially uniform width from end to end. The fuel gas valve has an orifice which is metered to inject gas into the mixing tube at velocities which are inverse to the rate of flow to the burner to insure a proper fuel-air mixture at low turn down. The burner ports are angled upwardly at such an angle as to direct gas above the level of the surrounding aeration pan to prevent pre-ignition accumulations of gas in the pan and consequent puff type ignition.

In the'drawings:

FIG. 1 is a side elevational view of portions of a gas range embodying structure according to the present invention, portions being broken away and shown in section to illustrate structural details.

FIG. 2 is an enlarged 'scale fragmentary view of 'a portion of the structure illustrated in FIG. 1.

FIG. 3 is a further enlarged scale fragmentary eleva tional view of a portion of the burner illustrating the shape of the burner ports.

FIG. 4 is a fragmentary sectional view illustrating the metered orifice of the gas valve.

FIG. 5 is an elevational view illustrating a modified form of burner.

Shown in the drawings is a gas range 10 having a fuel gas supply pipe 12 into which is tapped the'inlet of a valve 14 having an outlet nipple 16 onto which is threaded an adjustable hood 18 containing an outlet orifice 20 (FIG. 4) through which fuel gas is injected into a mixing tube 22. A mixture of fuel gas and primary air is fed from the mixing tube to a burner 24 according to the present invention, the burner being supported within the gas range by a mounting bracket 26.

v The gas range'has a top 28 with an opening 30 in the center of which burner 24 is disposed. A pan 32 fits within opening 30 and has a rim 34 which rests removably on top 28 of the range. A grate 35 has a ring 36 which rests removably on top 37 of rim 34. Lugs 38 depending from ring 35 fit within pan 32. Grate 35 is adapted to support a cooking vessel above burner 24. Pan 32 is referred to as a drip pan or frequently as an aeration pan in that it has a central opening 39 through which secondary air is provided to the burner ports 40 in burner 24. The pan portions 42 which are proximal to the burner are below the level of ports 40 while the pan portions 37 distal of the burner ports are above the level thereof. 1

Valve 14 has a ported inner plug '(not shown) which is rotated by a knob or handle 44 to provide fuel gas at varying rates of flow from pipe 12 into mixing tube22 and burner 24. The valve is preferably of the type disclosed in Mueller Pat. No. 2,260,474 wherein the valve plug is coupled with an axially movable member 46 provided with a metering needle 48 which is axially advanced and retracted relative to hood orifice 20 for a purpose to be described.

In the illustrated form of the invention, burner 24 has the shape of an inverted cup having a cylindrical side wall 50 and a closed-center end wall 52 forming the top of the burner. Side wall 50 has an outward shoulder 54 secured upon top of a bottom closure plate 56, a skirt 58 extending around the periphery of the plate. Mixing tube 22 opens through the center of plate 56 to introduce a mixture of fuel gas and primary air into the chamber 60 defined by top 52, side wall 50 and-plate 56.

contains burner ports 40. Ring 62 is angled inwardly from the vertical toward the center line of the burner cup so that ports 40 face upwardly from the horizontal at a like angle. This angle is such that a projection of the axis A of each port passes above the uppermost portions 37 of the aeration pan and the mounting ring 36 of grate 35 for a purpose to be described. Side wall nected by a return portion 72. Legs 68, extend along Side wall 50 has a port ring 62 adjacent top 52 which I lines which are angled equally but inopposite directions from the vertical. Leg 68 is defined by inner and

outer edges

74, 76 and an upper end'portion 78. Leg 70 is defined by inner and

outer edges

80, 82 and an upper end portion 84. Return portion 72 is defined by arcuate inner and

outer edges

86, 88. The inner and outer edges of the various slot portions are spaced apart substantially uniformly.

Inner edges

74, 80 of the legs adjoin inner edge 86 of return portion 72 in generally tangent directions at 90 and 92 respectively. Similarly,

outer edges

76, 82 of the legs adjoin outer edge 88 of the return portion in generally tangentdirections at 94 and 96 respectively. With this construction the slot shaped burner port 40 has substantially the same width throughout its length between end portions 78'and 84 thereof.

The

upper end portions

78, 84 of adjacent burner ports are close enough together so that chain ignition proceeds from one port to the next. The upper ends of adjacent ports, however,,are far enoughapart to insure that a flow of secondary air will rise between the flames at

adjacent end portions

78, 84 to prevent the adjacent flames from coalescing or balling together. This is particularly important in the illustrated form of the invention wherein burner top 52 has a closed center as dis- 1n burners 24 of the type having a closed-center top 52, no secondary air can reach flames F by rising through the center of the burner as in the open center,

' ring shaped burners. Consequently it is preferable with tinguished fromthe open center, ring shaped burner In use it will be assumed that initially the burner is turned off. When valve 14 is operated to turn the burner on, a certain amount of the fuel mixture issues from ports 40 before ignition occurs. Since the burner ports are aimed along axes A which pass above grate ring 36 and top 37 of pan 32, the issuing fuel gas is directed considerably above the well formed by the pan and the grate ring. The preignition flow of gas is thereby prevented from accumulating'in this well so that ignition occurs without the unpleasant thump or puff frequent in conventional burners.

The angle of axis A to the horizontal may be anywhere in the range from about 12 to about 21 for satisfactory operation. Preferably this angle is in the range of about 17 to 19. 1 v

The slot width of ports 40 ranges from a minimum-of about 0.032 inch to a maximum of about 0.040 inch for liquified petroleum gases or to a maximum of about 0.043 inch for natural gas. A width of about 0.040 inch has been found suitable for all around use witheither type of gas. For convenience in conventional manufacturing practices, a minimum slot width of about 0.037 inch is preferred. The minimum ratio of the length of the slot to its width is preferably about 10:1 where the length of the slot is measured along the generally U- shaped center line of the slot between

end portions

78 and 84.

Outer edges 76, 88, 82 define the major peripheral portions of port 40 and these portions are disposed in the path of upward flow of secondary air during operation of the burner. This insures an adequate supply of secondary air to ports 40.

A typical conventional burner having structuresimilar to burner 24 but being provided with conventional burner ports has a maximum output of about 6,000 BTU. By modifying such burner to incorporate ports 40 having the configuration defined herein, the maximum output of the burner is increased to about 12,000 BTU without increasing the size of the burner.

burners 24 to use valves 14 of the type disclosed in the Mueller patent referred to above. When this type'of valve is turned full on, metering needle 48 on its valve member 44 is fully retracted from outlet orifice 20 as illustrated in dotted lines in FIG. 4. When the valve-is turned down, metering needle 48 advances'to provide a progressively greater metering effect at orifice 20 which increases the velocity of the fuel gas entering mixing tube 22. The increased velocity causes inspiration and entrainment of a higher percentage of primary air which insures complete combustion of the fuel mixture at ports 40 during operation at low simmer rate.

The modified form of burner 24a illustrated in FIG. 5 is in general similar to that describedabove except that port ring 62 directly adjoins burner top 52 at 98 without the provision of an intermediate overhanging lip 66 as in burner 24. This structure is preferred as being more economical in gas ranges where it is unnecessary to provide the ultimate degree of flame stability at low turn down. Also burner 24a is illustrated as including a series of small carry-over ports 100 disposed in alternate arrangement between ports 40." This arrangement is utilized in some burners to facilitate chain ignition and to facilitate flame retention at high BTU output when a relatively strong current of secondary air flows upwardly past the burner ports.

We claim: 3

1. Gas burner structure having burner ports which comprise,

a first noncircular portion extending in one direction,

a second noncircular portion extending in another direction and an arcuate interconnecting portion,

each of said first and second portions having an end portion spaced from said interconnecting portion,

said port having a length between said end portions,

said port having a width which is substantially uniform throughout said length. r

2. The structure defined in claim 1 wherein said first, second and interconnecting portions are defined by edges, the edges of said first and second portions adjoining the edges of said interconnecting portion 'in directions substantially tangent to the arcs of said edges of said interconnecting portion.

3. Gas burner structure having burner ports which comprise,

a generally U-shaped slot having legs which are angled to the vertical,

said legs having upper end portions and having lower end portions which are interconnected by a return portion, said slot having a length between said upper end portions,

said slot everywhere along said length having a width substantially normal to said length, said width being everywhere no greater than 0.043 inch.

4. The structure defined in claim 3 wherein said width is everywhere in the range from about 0.032 inch to about 0.043 inch.

5. The structure defined in claim 4 wherein said width is everywhere in the range from about 0.037 inch to about 0.040 inch.

said port having a length between said end portions,

said port having a width which is substantially uniform throughout said length. 7. The structure defined in claim 6, wherein said first and second portions extend in directions angled oppositely to the vertical.

8. The structure defined in claim 7, wherein said first and second portions are angled substantially equally oppositely to the vertical.

9. The structure defined in claim 8, wherein said first and second portions extend along substantially straight lines.

10. The structure defined in claim 6 wherein said burner has the shape of an inverted closed-center cup with an end wall forming the burner top, said cup having a side wall portion adjacent said top containing said ports.

11. The structure defined in claim 10 wherein said side wall portion is disposed at an angle such that the ports therein face upwardly from the horizontal at an angle in the range from about 12 to about 21.

12. The structure defined in claim 11, wherein said upward angle is in the range from about 17 to about 19.

13. In combination with the structure defined in claim 10 a mixing tube and a valve operable to furnish fuel gas to said burner at different rates of flow,

said valve having an orifice whichopens into said mixing tube and which is metered to provide a gas velocity at said orifice inverse to said rate of flow of said burner.

Claims

1. Gas burner structure having burner ports which comprise, a first noncircular portion extending in one direction, a second noncircular portion extending in another direction and an arcuate interconnecting portion, each of said first and second portions having an end portion spaced from said interconnecting portion, said port having a length between said end portions, said port having a width which is substantially uniform throughout said length.

2. The structure defined in claim 1 wherein said first, second and interconnecting portions are defined by edges, the edges of said first and second portions adjoining the edges of said interconnecting portion in directions substantially tangent to the arcs of said edges of said interconnecting portion.

3. Gas burner structure having burner ports which comprise, a generally U-shaped slot having legs which are angled to the vertical, said legs having upper end portions and having lower end portions which are interconnected by a return portion, said slot having a length between said upper end portions, said slot everywhere along said length having a width substantially normal to said length, said width being everywhere no greater than 0.043 inch.

6. A gas burner structure having burner ports which comprise, a first noncircular portion, a second noncircular portion and an interconnecting portion, said first and second portions extending in directions which are angled to each other, said interconnecting portion turning through the angle between said directions, each of said first and second portions having an end portion spaced from said interconnecting portion, said port having a length between said end portions, said port having a width which is substantially uniform throughout said length.

7. The structure defined in claim 6, wherein said first and second portions extend in directions angled oppositely to the vertical.

11. The structure defined in claim 10 wherein said side wall portion is disposed at an angle such that the ports therein face upwardly from the horizontal at an angle in the range from about 12* to about 21*.

12. The structure defined in claim 11, wherein said upward angle is in the range from about 17* to about 19*.

13. In combination with the structure defined in claim 10 a mixing tube and a valve operable to furnish fuel gas to said burner at different rates of flow, said valve having an orifice which opens into said mixing tube and which is metered to provide a gas velocity at said orifice inverse to said rate of flow of said burner.