US3703166A

US3703166A - Liquid fuel cooking stove

Info

Publication number: US3703166A
Application number: US160747A
Authority: US
Inventors: Michael W White Jr; Jacques A Plamondon
Original assignee: Colorado Technologists Inc
Current assignee: Colorado Technologists Inc
Priority date: 1971-07-08
Filing date: 1971-07-08
Publication date: 1972-11-21
Anticipated expiration: 1989-11-21
Also published as: CA967070A

Abstract

A portable liquid fuel stove is disclosed herein which is particularly suited for cooking out of doors. The stove includes an annular shaped, cast fuel tank with a central opening having circumferentially spaced depending bottom ribs and upstanding top ribs both preferably cast with the fuel tank to form an integral unit. A control valve assembly preferably extends radially inwardly from the tank, and a fuel vaporizing section extends transverse to the valve assembly in axial alignment within the central opening in a lower portion of the tank. Vaporized fuel is passed from the fuel vaporizing section through an orifice disposed within the central opening in a lower portion of the tank to provide a stream of vaporized fuel. A burner cup in the central opening is substantially confined within the vertical extent of the tank to provide a mixing chamber. The flame produced heats the tank to pressurize the tank to force the fuel from the tank into the vaporizing chamber and vaporize the fuel in the vaporizing chamber for continuous burning.

Description

United States Patent White, Jr. et al.

Nov. 21, 1972 [54] LIQUID FUEL COOKING STOVE [72] Inventors: Michael W. White, Jr.; Jacques A.

Plamondon, both of Denver, Colo.v

[73] Assignee: Colorado Technologists Incorporated, Englewood, C010.

[22] Filed: July 8, 1971 [21] Appl. No.: 160,747

[52] U.S. Cl ..126/44, 431/243 [51] Int. Cl. ..F24c 5/02 [58] Field of Search ...126/44, 38; 431/243, 247, 242

[56] References Cited UNITED STATES PATENTS 694,173 2/1902 Neivbold ..126/38 2,444,444 7/1948 Howard ..126/44 2,498,682 2/1950 Howard ..126/38 2,928,386 3/1960 Keyt et al. ..126/44 Primary Examiner-Charles .l. Myhre Assistant ExaminerHarold Joyce Att0rneyReilly & Lewis ll'C o I VF -43 6 9 5 M 37 [57] ABSTRACT A portable liquid fuel stove is disclosed herein which is particularly suited for cooking out of doors. The stove includes an annular shaped, cast fuel tank with a central opening having circumferentially spaced depending bottom ribs and upstanding top ribs both preferably cast with the fuel tank to form an integral unit. A control valve assembly preferably extends radially inwardly from the tank, and a fuel vaporizing section extends transverse to the valve assembly in axial alignment within the central opening in a lower portion of the tank. Vaporized fuel is passed from the fuel vaporizing section through an orifice disposed within the central opening in a lower portion of the tank to provide a stream of vaporized. fuel. A burner cup in the central opening is substantially confined within the vertical extent of the tank to provide a mixing chamber. The flame produced heats the tank to pressurize the tank to force the fuel from the tank into the vaporizing chamber and vaporize the fuel in the vaporizing chamber for continuous burning.

23 Claims, 4 Drawing Figures PATENTED NOV 2 1 m2 vN R0 w 5 0 R WM 0 T HM T WP M A WA as YU HQ mm. MJ B 4 LEQUID FUEL COOKING STOVE This invention relates to an improved stove fueled by a liquid fuel which becomes vaporized by the heat generated by the stove and develops its own internal pressure for producing continuous burning.

Some attempts have been made to provide self-pressurizing stoves suitable for cooking out of doors on camping trips and in the military. Certain difficulties attendant to such stoves include general complexity of construction, a difficulty in providing a rapid start, a lack of effective fuel vaporization and in providing sufficient tank pressures to sustain continuous burning whereby in some cases an auxiliary pump is required to force the fuel into the burner. The present invention is intended to afford many advantages and improvements over previously known pressurized liquid fuel cooking stoves.

Accordingly, it is a general object of this invention to provide an improved liquid fuel stove capable of generating its own internal pressure for continuous burning, capable of effectively vaporizing the liquid fuel and capable of effectively shielding the flame against being put out by the wind or the like, particularly during starting.

Yet another object of this invention is to provide an improved cooking stove apparatus which is principally characterized by a simple, durable construction with a minimum number of parts which are relatively inexpensive to manufacture and assemble and has improved heat transfer characteristics making it highly effective in producing its own tank pressure and in vaporizing the liquid fuel for the burning thereof.

In accordance with the present invention, a preferred form has a hollow, generally annular cast fuel tank with a central opening having circumferentially spaced top upstanding ribs to support a cooking utensil above the fuel tank and having depending circumferentially spaced bottom ribsto support the tank above a supporting surface for efiective air circulation, the ribs being made integral with the tank. A control valve assembly extends radially fromthe tank and a vapor section extends transversely thereto and passes vaporized fuel through an orifice to produce a stream of vaporized fuel. A generally conical burner cup surrounds and extends upwardly from the orifice to define a mixing chamber, the cup being substantially confined within the vertical extent of the tank by having a major portion thereof located within the vertical extent of the central opening of the tank to shield the flame and provide good heat transfer to and from the tank whereby a stream of the vaporized fuel passes through the orifice and mixes with air in the burner cup and is deflected through annular spaces at the top of the cup to produce a flame which is characterized by a relatively even distribution.

Other objects, advantages and capabilities of the present invention will be more readily appreciated and understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a top plan view of a cooking stove embodying features of the present invention;

FIG. 2 is a bottom plan view of the cooking stove shown in FIG. 1;

FIG. 3 is a side elevation view of the stove shown in FIGS. 1 and 2 drawn approximately to scale; and

FIG. 4 is a vertical sectional view taken along lines 4-4 of FIG. 1 and the same side as FIG. 3.

Referring now the the drawings there is shown an annular or toroidal-shaped fuel tank 11 having a bottom wall 11a, top wall 11b and spaced inner and outer side walls and 11d, respectively, the corners of the tank being rounded and the inner side walls forming an axially extending central opening generally designated by numeral 12. The fuel tank has top ribs 13 extending upwardly from the top wall thereof and arranged at circumferentially spaced intervals along the top wall, the ribs terminating in flat top edges all of which are in the same plane to support a cooking utensil such as a skillet above the fuel tank. The fuel tank 11 also has a plurality of depending bottom ribs 14 extending down from the tank and arranged at circumferentially spaced intervals along the bottom wall to provide legs. The legs terminate in the same plane to support the fuel tank above a support surface permitting air to flow upwardly into the center of the tank to support combustion.

The fuel tank 11 has an inwardly directed feed tube projection or projecting part 15 provided with a radially extending internally threaded bore 16 opening into an inner sump portion 7, the sump portion being of relatively narrow width as compared to the full circumferential extent of the fuel tank. The sump portion 17 is located in a lower position than the bottom wall 11a of the tank so that the last remaining part of the fuel will pass from the tank. The fuel tank 11, upper and

lower ribs

13 and 14, and projecting portions 15 preferably are made as an integral one-piece unit by casting in a single casting mold from aluminum or a like material which makes a unit which is lightweight, extremely durable, relatively inexpensive to manufacture and capable of withstanding the required relatively high pressures.

In order to fill the fuel tank, a portion of the outer side wall 11d of the tank is formed with an annular inturned flange or filler neck 18 with internal threads to provide an inlet opening 19 formed therein. The filler neck 18 defines an annular expansion space or void 18a between it and the walls of the tank. A removable plug or filler cap 20 with a knurled head portion 20a and an externally threaded body portion 20b threads into the threaded flange 18 to close the fuel opening 19. The filler cap 20 is made hollow or bored out to form another expansion void 21 in the fuel tank. These expansion voids 18a and 21 prevent expansion of fuel (due to a rapid change in temperature) from bursting the tank walls. An O-ring type seal 22 is supported in a groove in the head portion 20a which bears against a recessed surface in the outer side wall of the tank to form a seal so as to prevent loss of pressure in the tank. A generally C-shaped ring 25 is mounted on the plug 20 and has intumed end portions inserted into openings in the head portion 20a to facilitate the carriage of the tank on a belt and provide added leverage for tightening and loosening the plug. The fuel tank may be initially filled through opening 19 by a suitable liquid fuel represented at 26. The fuel may be a variety of types such as kerosene, gasoline or the like which will vaporize rapidly when heated.

A control valve assembly for regulating the fuel flow from the fuel tank 11 includes a valve housing or valve body 31 having oppositely disposed end portions 32 and 33. End portion 32 is provided with external threads and is threaded into projecting part to secure the valve body to the tank. End portion 33 has internal threads. The valve body 33 has a longitudinal bore 34 extending throughout its lengthwise extent through which an elongated metering rod or needle valve stem 37 extends. The valve stem 37 had an externally threaded portion 38 which threads into internal threads 39 formed in the longitudinal bore 34 of the valve body. The valve stem has a gradually tapering end portion 41 which is adapted to engage a tapered complementary shaped valve seat 42 formed along the horizontal bore 34. The tapered end portion 41 and the valve seat 42 is quite gradual or only slightly tapered to provide very close metering or fuel regulation.

The valve stem terminates at its free central end in a knob 43 which is turned by the user to open and close the control valve assembly. A cap 44 with a head portion 44a and external threads is threaded into the threaded end portion 33 and a gas seal 45 is provided inside the valve body and around the stem to prevent gas leakage along the stem. The gas seal 45 is shown to comprise a pair of rings sandwiched between a pair of washers, all of which encompass the stem rearwardly of the threaded portion 38. The threading of the stem through the valve body serves to open and close the flow passage thereof and the valve body closely regulates the flow of fuel from the tank through the valve body.

A vaporizing chamber 49 is formed in flow communication with the horizontal bore by providing a vertically disposed bore 46 with internal threads extending through the top of the valve body 31 and then extending into the longitudinal bore 34. A hollow nozzle member 48 having a hexagonal head portion 48a and an externally threaded part 48b with an internal bore threads into the internal threads in the vertical bore 46 to define a vaporizing section forming the vaporizing chamber 49. The stem 37 has a recessed portion 37a which is beveled at the ends and cooperates with the lower end of threaded part 48a extending into the longitudinal bore to prevent the stem from being removed and/or opening of the valve causing an excessively high flame. A narrow restricted orifice 51 is formed in the head portion 48a to discharge the vaporized fuel in a fine spray or jet as it passes from the vapor chamber. The internal bore of the nozzle member 48 has a main bore portion of uniform cross-section and an upwardly tapered bore portion 52 leading into the restricted orifice 51. A free-rolling ball valve 53 is carried in the bore of the nozzle member 48 and engages the tapered surface 52 which acts as a valve seat therefor to prevent the loss of fuel when the tank is placed in an inverted position. The nozzle member 48 has a tapered portion 48c which is complementary to a chamfer in the vertical bore forcing the bottom of the burner cup 55 to form a chamfer.

As best seen in FIG. 4, the nozzle member 48 and orifice 51 are located within the center of the tank and at a point substantially below the midpoint of the tank along a vertical line through the axis of the fuel tank and is preferably approximately at the fuel level of the bottom of the tank. This allows the fuel to flow by gravity feed from the tank into the vapor chamber for the starting of the stove and also locates the nozzle member and vapor chamber relative to the tank so that they will receive a substantial amount of heat from the tank.

A vapor-air mixing assembly located above the nozzle member 48 and within the center of the tank of the stove comprises a burner cup 55 having an inverted bell shape or conical shape with an upwardly divergent side wall portion 550 and an inturned base portion 55b provided with a central opening therein. The side wall portions 55a have openings 56 to admit primary air into the mixing chamber 57 formed by the cup for mixing with the fuel vapor emitting from the nozzle with primary air coming in through the side openings 56. The burner cup is substantially confined within the vertical extent of the tank in that a major portion of the cup is located within the vertical extent of the tank. This provides a substantial shielding of the flame and affords good heat transfer between the tank and'cup.

A flame deflector plat 58 extends across the top of the burner cup 55 with the deflector plate being of a concave-convex shape having a plurality of circumferentially spaced outwardly extending relatively nar row tabs 59 which are bent to releasably engage the upper edge of the cup and leave annular spaces 61 between the tabs through which a mixture of fuel vapor and air pass to produce a flame above the deflector plate during the operation thereof. The annular spaces 61 and location of the top of the cup afford a burner flame more closely resembling that of the gas range, with a more even flame and heat distribution, and an essentially blue flame is produced. The nozzle member 48 extends through the opening in the base portion 55b and threads into the vertical base of the valve body and the head portion 48a engages the upper surface of the base portion so as to releasably secure the burner cup 55 in place on top of the valve body with the threading of the nozzle member into the bore 46 forming a chamfer in the bottom of the cup, as best seen in FIG. 4.

In the entire sequence of operation for the abovedescribed stove, the control valve is initially opened only slightly to permit a relatively small quantity of fuel to pass by gravity feed or flow into the vapor chamber 49 and up through the nozzle orifice 51. The valve is then closed and the fuel is lit either by introducing a match into the mixing chamber 57 through the side opening or actuating a suitable spark generator device located in the mixing chamber or adjacent thereto. This produces an initial flame in the mixing chamber 57 which in turn burns a portion of the fuel in the vapor chamber and the fuel in the vapor chamber is heated and begins to vaporize so that after a period of fifteen to thirty seconds of burning in the mixing chamber the fuel begins to vaporize within the vapor chamber causing a hissing effect. The control valve assembly is then opened slightly and the fuel continues to vaporize in the vapor chamber as a result of its being heated up by the flame.

The fuel tank which begins to become heated by flame has vaporized fuel passing through the orifice which mixes with primary air in the mixing chamber to produce a flame which gradually begins to extend through the top openings 61. After initial heating, the flame moves from inside the mixing chamber to above the mixing chamber where it combines with secondary air above the deflector plate and provides a substantial flame above the deflector plate. The deflector plate serves to spread the flame out through the top openings where it is in close proximity to and impinges on the fuel tank to heat the fuel tank. As the flame burns a pressure begins to build up in the fuel tank which tends to force the fuel from the tank past the control valve assembly and into the vapor chamber with the vaporized fuel being forced up through the orifice 51 in a continuous feeding of the liquid fuel into the vaporizing chamber under pressure provided in the tank.

During the lighting operation the flame stays inside the mixing chamber 57 until proper draft occurs and it has been found that the flame is very difficult to blow out. This point is important as to the overall operation because many camper, hiker, fisherman and hunter finds himself in a windy unprotected area, and to build even a small wood fire becomes difficult due to the wind. This stove allows one to light it in winds of a substantial velocity such as up to 30 mph and it will stay lit because of the flame being protected from the wind during the generation period.

It is therefore to be understood that various modifications and changes may be made in the detailed construction and arrangement of parts comprising the preferred form of the present invention without departing from the spirit and scope thereof.

What is claimed is:

1. Cooking stove apparatus comprising:

a generally annular fuel tank with a central opening,

control valve means for regulating the flow of fuel from the tank having a fuel vaporizing section at a discharge end thereof located within the central opening at the bottom of said tank,

a nozzle disposed within the central opening at the bottom of the tank having an orifice for discharging vaporized fuel passing from said fuel vaporizing section in a fine stream, and

means defining a mixing chamber disposed within said central opening and substantially confined within the vertical extent of said tank, said mixing chamber mixing air with the stream of vaporized fuel passing through said orifice to produce a flame whereby heat produced by the flame heats the tank to pressurize the tank and vaporize fuel in the fuel vaporizing section.

2. Cooking stove apparatus as set forth in claim 1 wherein said nozzle orifice is located at approximately the level of the bottom of the tank whereby the fuel may drain by gravity flow from the tank through said orifice.

3. Cooking stove apparatus as set forth in claim 1 wherein said mixing chamber is defined by a generally conical cup-shaped burner member made of a heatconductive material having walls in close proximity to the inner walls of said tank to transfer heat produced by the flame to said tank.

4. Cooking stove apparatus as set forth in claim 3 wherein said cup-shaped burner member diverges upwardly and terminates in a top opening slightly above the top wall of the fuel tank and a flame deflector partially covering said top opening and forming therewith annular openings along the outer periphery of the cupshaped burner member for the discharge of a vaporized fuel and air mixture to produce a flame.

5. Cooking stove apparatus as set forth in claim 4 wherein said cup-shaped burner member has openings in the side thereof to admit primary air into the mixing chamber.

6. Cooking stove apparatus as set forth in claim 1 wherein said fuel tank has depending ribs at circumferentially spaced intervals along the bottom thereof to support the tank above a support member and upstanding ribs at circumferentially spaced intervals along the top of the tank to support a cooking utensil above the top of the tank.

7. Cooking stove apparatus as set forth in claim 6 wherein said tank and bottom and top ribs are cast as an integral unit.

8. Cooking stove apparatus as set forth in claim 1 wherein said control valve means includes a valve body mounted along an inner side wall of the tank which extends radially inwardly thereof, said valve body having a longitudinal bore provided with a tapered valve seat in flow communication with the inside of the tank and a valve stem having a tapered portion adapted to move through said bore to meter the fuel flow from said tank into said vaporizing section.

9. Cooking stove apparatus as set forth in claim 8 including a recess in the stern cooperating with said nozzle to limit the movement of the stem in the valve body.

10. Cooking stove apparatus as set forth in claim 8 wherein said valve body has an upper portion formed with a vertical bore opening into said longitudinal bore, said nozzle being fitted in said vertical bore for forming said fuel vaporizing section.

11. Cooking stove apparatus as set forth in claim 1 wherein said nozzle contains a movable valve member adapted to close the orifice when the nozzle is inverted.

12. Cooking stove apparatus as set forth in claim 11 wherein said movable valve member is in the form of a ball.

13. Cooking stove apparatus as set forth in claim 1, said fuel tank having means defining an expansion void for the fuel.

14. Cooking stove apparatus as set forth in claim 12 wherein said means defining an expansion void includes a radially extending filler neck flange formed in a side wall of the tank leaving a space between the filler neck flange and the inner walls of thetank.

15. Cooking stove apparatus as set forth in claim 12 wherein said means defining an expansion void includes a removable plug in the tank having a hollow portion in the plug.

16. Cooking stove apparatus comprising:

a generally toroidal-shaped fuel tank with a central opening,

control valve means for regulating the flow of fuel from the tank having a fuel vaporizing section at a discharge end thereof located within the central opening of said tank,

a nozzle disposed within the central opening having an orifice for discharging vaporized fuel passing from said fuel vaporizing section in a fine stream, said orifice being located below the midpoint of the vertical extent of the tank so that fuel may flow by gravity feed into said orifice, and

means defining a mixing chamber within said central opening and surrounded by said tank for mixing air with the stream of vaporized fuel passing through said orifice to produce a flame whereby heat produced by the flame heats the tank to pressurize the tank and vaporize fuel in the fuel vaporizing section.

17. Cooking stove apparatus comprising a generally annular fuel tank with a central opening, control valve means extending radially inwardly from the tank for regulating the flow of fuel from the tank, said valve means having a fuel vaporizing section in flow communication therewith, a nozzle member in flow communication with the vaporizing section having an orifice for discharging the vaporized fuel in a fine stream, said orifice being located at least below the midpoint of the vertical extent of the tank so that fuel may flow by a gravity feed into said orifice, and a burner cup extending upwardly from the nozzle member defining a mixing chamber for mixing air with the fine stream of vaporized fuel to produce a flame, said burner cup being substantially confined within the tank with a major portion of the burner cup being located within the vertical extent of said tank whereby heat produced from the flame produces a pressure in the tank to force the fuel into the vaporizing chamber and heat from the tank transmitted to the vaporizing section vaporizes the fuel in the vaporizing chamber.

18. Portable self-pressurizing cooking stove apparatus comprising:

a toroidal-shaped integrally cast fuel tank with a central opening made of a heat conductive material, said fuel tank having a removable plug in sealed engagement with a wall portion thereof for the filling of the tank with fuel, a hollow, radially inwardly extending projecting portion forming a fuel feed line connector from the tank and having a sump portion opening into the projecting portion, and a flanged neck portion defining a fill opening into the tank, said neck portion being spaced from the inner walls of the tank to form a fuel expansion void, said fuel tank having depending ribs at circumferentially spaced intervals along the bottom of the tank to support said tank above a support surface and upstanding top ribs at circumferentially spaced intervals along the top of the tank to support a cooking utensil above said tank, said bottom and top ribs being cast integral with said tank,

a control valve assembly including a valve body with a longitudinal bore releasably secured to aid projecting portion and extending radially inwardly from said tank, said horizontal bore having a tapered valve seat portion, aneedle-type valve stem extending through said longitudinal bore having a tapered portion movable axially along said valve seat to meter fuel flow from the fuel tank, said valve body having an upright transverse bore opening into said longitudinal bore,

a hollow nozzle member threaded into said upright bore to form a vaporizing chamber for vaporizing fuel metered past said valve stem, said nozzle member having a restricted orifice for discharge of the vaporized fuel in a jet stream, said orifice being located at approximately the bottom of the tank so that fuel will flow by the force of gravity through said orifice, said nozzle member projecting into said upright bore and into engagement with a beveled recess in said valve stem to limit the movement of the valve stem,

mixer assembly including a generally conical burner cap defining a mixing chamber surrounding and extending upwardly from said nozzle orifice within the central opening of the fuel tank, a major portion of the burner cap being located within the vertical extent of the tank, said burner cap having side openings to admit primary air into said mixing chamber and having a deflector plate across the top thereof to deflect the flame through annular top openings along the outer edges of the burner cup, said nozzle member being in engagement with the bottom of the burner cup to secure the cup to the valve body and transfer heat to the vaporizing chamber whereby heat produced by the flame heats the tank to pressurize the tank and vaporize the fuel in the vaporizing chamber.

19. Portable self-pressurizing cooking stove apparatus as set forth in claim 18 wherein said nozzle member has a beveled edge adapted to be received by an inclined depression at the top of said upright bore to incline the bottom of the burner cup at an angle in its engagement with the burner cup and the valve body.

20. In a self-pressurizing stove, the combination comprising:

a generally annular shaped cast fuel tank with a central opening, said tank including spaced inner and outer side walls, a top wall and a bottom wall arranged to form an inner fuel chamber, said tank having an opening into the fuel chamber formed in the outer wall with a removable plug in said opening, a flanged portion extending inwardly from an inner surface of said outer wall at said opening to form a fuel expansion void, and a projecting portion extending inwardly from the inner wall having a bore in communication with said fuel chamber, said tank having depending rib portions at circumferentially spaced intervals along the bottom wall to support said tank and upstanding top ribs at circumferentially spaced intervals'along the top wall of the tank, said flanged portion, projecting portion, depending ribs and upstanding ribs being cast integral with said tank, and

a valve and burner assembly mounted on said tank, said assembly including a valve body connected to said projecting portion and extending radially inwardly therefrom having a bore in communication with the fuel chamber and a valve stem movable through the bore to regulate the flow of fuel therethrough, and a burner mounted on said valve body extending generally transverse thereto and coaxially arranged in said central opening of said tank.

21. In a self-pressurizing stove is set forth in claim 20 wherein said valve body has external threads which thread into internal threads in said projecting portion.

22. In a self-pressurizing stove, the combination comprising:

a generally annular fuel tank having a vertical axis and walls defining a central opening and an inner fuel chamber, and

means defining a fuel discharge orifice in said central opening at the bottom of the tank and a vapor chamber below and in flow communication with said fuel discharge orifice, said vapor chamber being in flow communication with said fuel chamber, said means including a valve body with a bore and valve stem, said valve body supported by an inner wall of said tank and extending radially inwardly therefrom, said valve stem being movable in the bore to regulate the fuel flow from the fuel chamber through said vapor chamber and out said fuel discharge orifice.

Claims

1. Cooking stove apparatus comprising: a generally annular fuel tank with a central opening, control valve means for regulating the flow of fuel from the tank having a fuel vaporizing section at a discharge end thereof located within the central opening at the bottom of said tank, a nozzle disposed within the central opening at the bottom of the tank having an orifice for discharging vaporized fuel passing from said fuel vaporizing section in a fine stream, and means defining a mixing chamber disposed within said central opening and substantially confined within the vertical extent of said tank, said mixing chamber mixing air with the stream of vaporized fuel passing through said orifice to produce a flame whereby heat produced by the flame heats the tank to pressurize the tank and vaporize fuel in the fuel vaporizing section.

3. Cooking stove apparatus as set forth in claim 1 wherein said mixing chamber is defined by a generally conical cup-shaped burner member made of a heat-conductive material having walls in close proximity to the inner walls of said tank to transfer heat produced by the flame to said tank.

4. Cooking stove apparatus as set forth in claim 3 wherein said cup-shaped burner member diverges upwardly and terminates in a top opening slightly above the top wall of the fuel tank and a flame deflector partially covering said top opening and forming therewith annular openings along the outer periphery of the cup-shaped burner member for the discharge of a vaporized fuel and air mixture to produce a flame.

9. Cooking stove apparatus as set forth in claim 8 including a recess in the stem cooperating with said nozzle to limit the movement of the stem in the valve body.

14. Cooking stove apparatus as set forth in claim 12 wherein said means defining an expansion void includes a radially extending filler neck flange formed in a side wall of the tank leaving a space between the filler neck flange and the inner walls of the tank.

16. Cooking stove apparatus comprising: a generally toroidal-shaped fuel tank with a central opening, control valve means for regulating the flow of fuel from the tank having a fuel vaporizing section at a discharge end thereof located within the central opening of said tank, a nozzle disposed within the central opening having an orifice for discharging vaporized fuel passing from said fuel vaporizing section in a fine stream, said orifice being located below the midpoint of the vertical extent of the tank so that fuel may flow by gravity feed into said orifice, and means defining a mixing chamber within said central opening and surrounded by said tank for mixing air with the stream of vaporized fuel passing through said orifice to produce a flame whereby heat produced by the flame heats the tank to pressurize the tank and vaporize fuel in the fuel vaporizing section.

18. Portable self-pressurizing cooking stove apparatus comprising: a toroidal-shaped integrally cast fuel tank with a central opening made of a heat conductive material, said fuel tank having a removable plug in sealed engagement with a wall portion thereof for the filling of the tank with fuel, a hollow, radially inwardly extending projecting portion forming a fuel feed line connector from the tank and having a sump portion opening into the projecting portion, and a flanged neck portion defining a fill opening into the tank, said neck portion being spaced from the inner walls of the tank to form a fuel expansion void, said fuel tank having depending ribs at circumferentially spaced intervals along the bottom of the tank to support said tank above a support surface and upstanding top ribs at circumferentially spaced intervals along the top of the tank to support a cooking utensil above said tank, said bottom and top ribs being cast integral with said tank, a control valve assembly including a valve body with a longitudinal bore releasably secured to aid projecting portion and extending radially inwardly from said tank, said horizontal bore having a tapered valve seat portion, a needle-type valve stem extending throUgh said longitudinal bore having a tapered portion movable axially along said valve seat to meter fuel flow from the fuel tank, said valve body having an upright transverse bore opening into said longitudinal bore, a hollow nozzle member threaded into said upright bore to form a vaporizing chamber for vaporizing fuel metered past said valve stem, said nozzle member having a restricted orifice for discharge of the vaporized fuel in a jet stream, said orifice being located at approximately the bottom of the tank so that fuel will flow by the force of gravity through said orifice, said nozzle member projecting into said upright bore and into engagement with a beveled recess in said valve stem to limit the movement of the valve stem, a mixer assembly including a generally conical burner cap defining a mixing chamber surrounding and extending upwardly from said nozzle orifice within the central opening of the fuel tank, a major portion of the burner cap being located within the vertical extent of the tank, said burner cap having side openings to admit primary air into said mixing chamber and having a deflector plate across the top thereof to deflect the flame through annular top openings along the outer edges of the burner cup, said nozzle member being in engagement with the bottom of the burner cup to secure the cup to the valve body and transfer heat to the vaporizing chamber whereby heat produced by the flame heats the tank to pressurize the tank and vaporize the fuel in the vaporizing chamber.

20. In a self-pressurizing stove, the combination comprising: a generally annular shaped cast fuel tank with a central opening, said tank including spaced inner and outer side walls, a top wall and a bottom wall arranged to form an inner fuel chamber, said tank having an opening into the fuel chamber formed in the outer wall with a removable plug in said opening, a flanged portion extending inwardly from an inner surface of said outer wall at said opening to form a fuel expansion void, and a projecting portion extending inwardly from the inner wall having a bore in communication with said fuel chamber, said tank having depending rib portions at circumferentially spaced intervals along the bottom wall to support said tank and upstanding top ribs at circumferentially spaced intervals along the top wall of the tank, said flanged portion, projecting portion, depending ribs and upstanding ribs being cast integral with said tank, and a valve and burner assembly mounted on said tank, said assembly including a valve body connected to said projecting portion and extending radially inwardly therefrom having a bore in communication with the fuel chamber and a valve stem movable through the bore to regulate the flow of fuel therethrough, and a burner mounted on said valve body extending generally transverse thereto and coaxially arranged in said central opening of said tank.

22. In a self-pressurizing stove, the combination comprising: a generally annular fuel tank having a vertical axis and walls defining a central opening and an inner fuel chamber, and means defining a fuel discharge orifice in said central opening at the bottom of the tank and a vapor chamber below and in flow communication with said fuel discharge orifice, said vapor chamber being in flow communication with said fuel chamber, said means including a valve body with a bore and valve stem, said valve body supported by an inner wall of said tank and extending radially inwardly therefrom, said valve stem being movablE in the bore to regulate the fuel flow from the fuel chamber through said vapor chamber and out said fuel discharge orifice.