US1886420A - Carbureting device for lighting stoves - Google Patents

Description

Nov. 8, 1932. w. oLsEN ET AL 1,886,420

GARBURETING DEVICE FOR LIGHTING vSIOVES Filed June 7, 1928 Patented Nov. 8, 1932y taten i; ot-Fi iii WALTER OLSEN AND SOPHUS RASMU'SSEN, 0F ALBERT LEA, MINNESOTA CARBURETING DEVICE FOR LIGHTING STOVES l Application filed June 7, 1928.

This invention relates to devices, such as stoves, lanterns, irons, heaters etc., using a liquid hydrocarbon fuel such as gasoline, which is vaporized and burned, and it relates particularly to what may be termed instant lighters for such devices. Such devices utilizing a liquid hydrocarbon fuel which is vaporized and burned, are now used in large numbers and prior to an invention 'i0 by John E. McCutchen upon which a United States patent has recently issued No. 1,718,- 473, dated June 25, 1929, entitled Gil burning device, it was the common practice in such devices, when initially lighting the same, to heat a vaporizing member to which liquid fuel was supplied either by burning a small quantity of the fuel under the vaporizing member in a priming cup, or byholding a torch under the vaporizing member for a short time. The McCutchen invention eliminated the necessity for preheating the vaporizing member, in initially lighting the device, as just described, but this McCutchen device is open to certain serious objections. In the McCutchen device, there is provided a burner, the flame -from which .plays on to a vaporizing tube Within which'l-iquid fuel is adapted to be vaporized for supplying the requirements of the burner. A tank containing liquid hydrocarbon fuel and compressed air is also provided and into'this tank a-main tube extends having a Small orifice located below thc liquid level of the tank. A branch tube is also located in the tank and this branch tube has an open upper end located Within and freely communicating with the air space of the tank and the branch tube has a lower end communicating with the main tube adjacent the orifice there- 43 in. A valve controls the main tube and a Conduit runs from this tube to the vaporizing tube of the burner.A The orifice in the main tube located Within the tank is proportioned relative to the outlet end of the vaporizing 43 tube, so that as the Valve is opened, a small quantity of liquid fuel will flow in a regulated stream into the tube in the tank, While at the same time a stream of compressed air from the top Aof the tank will flow from the 3 branch tube into the main tube iii the tank Serial No. 283,579.

' to mix with the liquid fuel and supply aimxtube located in the tank. This back pressure, according to McCutchens theory, slows up the flow of liquid and air through the main tube in the tank, permitting the liquid fuel to flow up through the orifice into the main tube and through the conduit and the vaporizing tube to supply the burner de mand and close the outlet of the branch tube 1n the tank to the main tube therein to seal o ff the air supply. As a lnatter 0f fact, in this Mc- Cutchen device, this air supply to the main tube is never completely cut off as long as any considerable pressure remains on the air in the tank. It is true that as the Vaporizng tube is heated so that the liquid fuel supplied to the vaporizing tube is vaporized, that the passage of air from thebianch tube to the main tube in the tankis checked, but it is likewise true that small quantities of air from the top of the tank will constantly pass to the main tube in the tank and thence to the burner as long as the burner remains in operation. In other Words, as long as the burner remains in operation, the supply of compressed air in the tank will be constantly depleted. rlhis necessitates the renewal of the supply of fresh air in the tank at frequent intervals, if the burner which is instantly lighted Without preheating the gen-` erating tube supplying the same, is to be kept in continuous operation.

We have discovered that if the passage through the orifice in the main tube located in the tank can be suddenly enlarged after the burner has been initially ignited and after the vaporizing tube has been heated, liquid fuel will run intothis main tube in the tank in such quantity as to completely seal Off the passage supplying air from the y conduit supplying the same and the main top of the tank to the main tube in the tank and thereby completely prevent the escapeof compressed air from the top of the tank by way of the burner to eliminate the necessity for renewing the supply of compressed air in the tank at frequent intervals during the continuous operation of the burner. The passage through the orifice in the main tube of the tank must be enlarged only after the vaporizing tube supplying the burner has been heated. If the passage through the oriice were made large enough to accomplish this air sealing function after the vaporizing tube had been heated and if the passage through the orifice was of the same size prior to the time that the vaporizing tube was heat ed and when the cold burner was initially ignited, no air would be supplied with liquid fuel to the vaporizing tube to produce an initial combustible mixture which could be instantaneously lit and the burner could not be lit without first preheating the Vaporizing tube as by a torch or by burning a small quantity of liquid fuel in a cup underneath the vaporizing tube.

It is the main object of this invention, therefore, to provide an instant lighting structure of the class described and wherein the passage through an orifice in a tube located within the liquid space of a tank containing liquid fuel under air pressure, can

` be suddenly enlarged.

A more detailed object is to provide means for cleaning such an orifice.

Another object is to provide a novel, improved simple, inexpensive and efficient lighting structure for devices, such as stoves, lanterns, irons, heaters etc., utilizing a liquid hydrocarbon fuel which is vaporized and burned.

These and other objects and advantages of the invention will be more fully set forth in the following description, made in connection with the accompanying drawing, wherein like reference Characters refer to similar parts throughout the several views and in which Fig. l is a partial plan view of the stove having the invention applied thereto;

Fig. 2 is a 'vertical section taken on line 2 2 of Fig. 1 as indicated by the arrows;

Fig. 3 is a vertical section taken on line 3-3 of Fig. 1 as indicated by the arrows;

Fig. 4 is a vertical section taken on line 4 4 of Fig. 3 as indicated by the arrows and Fig. 5 is a view similar to Fig. 4, showing a modification.

Referring to the drawing, a stove is shown comprising a top plate 10 secured to and supported by a frame 11 shown as rectangular in form and extending downwardly from said .top plate, said top plate being secured by screws 13. A fuel tank 14 is supported at one end of the frame 11, being secured thereto by straps 15 secured to said frame. The

stove comprises one or more main burners 16 disposed below openings in top plate 10 and connected to a mixing chamber 17 secured to the top plate by screws 18. A vaporizing member or tube 19 connects with mixing chamber 17 and extends over one of the burners 16 as shown, said tube having valves for opening and closing the same operated by hand wheel 20. Said tube 19 is connected to the .fuel tank by a small conduit or tube 21 connected to a fixture 22 secured to tank 14, which fixture carries a pressure gauge 23 for indicating the pressure in the tank and also comprises a valve 24. An auxiliary burner 25 is provided, and although this burner may` be used independently of burner 16, it is shown as forming a starting burner for heating tube 19, and while this burner may be variously located, in the embodiment of the invention illustratcd it is shown as disposed below tube 19 and between burners 16 and mixing chamber 17. The burner 25 comprises a mixing chamber having an open upper end 25a into which projects a fuel supplying and vaporizing tube 255 which is of quite small size. The mixing chamber also has an opening 250 forming the ignition opening disposed below tube 25?). Tube 25o connects with a valve body 26 having a valve seat adjacent one end engaged by a valve formed on the stem 27 which is operated by the hand wheel 28. Valve body 26 has a depending lug to which is secured a rod 29 forming a support for the mixing chamber of burner 25. The part connecting burner 16 with mixing chamber 17 has a pan 17a disposed below the opening 250 to catch any fuel overiowing therefrom and to guide the same to said mixing chamber 17. A conduit 30 connects valve body 26 to the fuel tank 14 and this conduit is connected to a valve body or fixture 31 secured in the top of tank 14 by being threaded into a plug 32 secured in said tank. A tube 33 is secured to valve body 31 within tank 14 and extends downwardly therein so that its lofwer end is disposed adjacent the bottom of said tank and in the fuel in said tank. Tube 33 is connected at its lower end to another tube 34 surrounding and spaced therefrom, which tube 34 has an open upper end disposed in the air space in tank 14. Tube 33 has a plurality of comparatively small openings 33a therein adjacent its lower end. affording communication with theinner side of tube 34,-. A plug 35 is threaded -Into tube 33 and has a small central opening therethrough which is tapered at its lower end, whichopening communicates with the opening in tube 33. The shell 36 is threaded on the bottom of the tube 34 and projects downwardly from the same, having a cylindrical opening surrounding plug 35 and having a screen 37 extendng across its lower end. A valve stem 3S is threaded in member 31, having an operating about half a turn.

38 has a valve 38a closing communicaton' with tube 33, said stem having` a projecftion 38?) extending therefrom downwardly through member 31 and tube 33, said portion 38?) having a reduced needle 380 projecting downwardlyl through the opening in plug 35, needle 38e having a conical pointed end.

ln operation, when the stove is cold and not in operation, all the valves are closed. `When the stove is to be started, valve 27 is opened and valve 38a is raised from its seat for a short distance by turning wheel 39 This initial turning movement of valve 38a and the valve stem 38 is not sufficient to withdraw the needle 380 upwardly from the lower end of theplug 35 sufficiently to materially increase the size of the passage through the plug As a result, but a very small passage through the plug 35 to the tube 33 will be initially provided, this passage being preferably slightly larger than the passage through the outlet end of vvaporizing tube Q56. A certain amount of gasoline or fuel will now pass through the needle obstructed opening in plug 35 into tube 33 and at the same time compressed air from the top of the tank 14 will be supplied to the tube 33 through tube 34 and opening 33a. The air running into tube 33 mixes with the liquid fuel in this tube and passes through the tube and out through conduit 30 into vaporizing tube 25?) and thence into the mixing chamber of burner 25 from whence it issues through the opening 250, where it can be instantly ignited with a match or other lighting device. 0f course, liquid fuel from the tank 14 tends to move through the passage in plug 35 by reason of the difference in levels between the surface of the liquid fuel in the tank and the bottom of plug 35. The air pressure on the surface of the liquid fuel within the tank 14 is practically the same as the air pressure within the tube 33 at this time, because communication is afforded between the air at the top of the tank and the tube 33 through the tube 34 and air openings 33a. The restricted passage in the plug 35 offers considerable frictional resistance to the travel of liquid fuel into tube 33 through the same and only a small quantity of liquid fuel will enter the tube 33 through this passage. This small quantity of liquid fuel will be entrained by theair passing to the tube 33 from the tube 34 and air openings 33a and, as

a result, a column of liquid fuel in tube 33 cannot be built up to such a height as to seal 'olf the air openings 33a.. The combustible mixture formed by the compressed air issuing from tank 14 and the liquid fuel'from tank 14v causes the burner 25 to operate for a short time, such asa few seconds, until vaporizing tube 25?) is heated. As soon as tube 25?) becomes thoroughly heated, any fuel supplied to this tube in liquid form will readily vaporize. As the vaporizing tube 256 becomes heated therefore, the mixture running through this tube will vaporize and will expand to many times its original 4volume, thereby creating a back pressure in conduit 30 and tube 33. This back pressure slows down the movement of the air in tube 33and thereby permits a greater quantity of liquid fuel from the liquid space in the tank 14 -to travel throughthe passage in plug 35 to the tube The proportion of liquid fuel relative to compressed air in the tube 33 is therefore increased 'due to the back pressure caused by the vaporized gases in the vanorizing tube 256. It is found, however, that the liquid fuel or gasoline will not rise in the tube 33in sufficient quantity to completely seal off the supply of air to the tube 33 and, as a result, small quantities of air usually in bubble form will travel from the top of the tank 14 through tube air openings 33a and tube 33 to the vaporizing tube 255 as long as the burner 25 remains in operation without enlarging the liquid fuel passage into the tube 33. In other words, if the burner 25 is maintained-in continuous operation, the air supply in tank 14 will be continuously depleted if the liquid fuel passage tothe tube 33 remains of the same small size necessary for use to supply the requisite proportions of liquid fuel and air to the tube 33 for initial ignition of the burner Q5 for starting when the vaporizing tube 25.7) is cold.

As'soon as vaporizing tube Q57) becomes thoroughly heat-ed` the wheel 39 is turned to carry valve 38a high above its seat, and at the same time to carry needle 380 either upwardly into the enlarged portion of the opening in plug 35 or completely7 above and out of the opening. As the needle 380 is cfarried into the enlarged portion of the opening of plug 35 above the lower tapered portion thereof, or as the needle 330 is carried completely out of this opening, the passa ge through the opening for the travel of liquid fuel from the fuel space in the tank 14 to the tube 33 is greatly enlarged. As a result, the major part of the frictional resistance hitherto offered to the travel of liquid fuel from the fuel space in the tank to the tube 33 through theopening in plug 35 will be eliminated and the liquid fuel will quickly run into the tube 33 to seal the openings 33a completely and to cause the rise of liquid fuel in the annular space be-1 tween tube 34 andy 33 to lapproximately the same level as the level of liquid fuel in the tank 14. It will then be no longer possible n for compressed air to travel from the top of the tank 14 through tube 34 and openingsf33a to tube 33 and nothing but liquid fuel will pass through tube 33 and conduit 30 to the vaporizing tube 256. In other words, the burner 35 may be operated indefinitely without depleting the supply of compressed air in tank 14.

Although the burner 25 is complete in itself and can be operated for any desired length of time, in the embodiment shown, this burner is utilized chiefly for heating the main vaporizing tube 19 which supplies the main burner 16. Accordingly, after the burner 25 has been in operation for a short time, such as a minute, the main vaporizing tube 19 will become heated whereupon the va ve controlled by the wheel 2O may be opened and the main burner 16 may be lit. Fuel admitted to main vaporizing tube 19 will be vaporized and will pass to mixing chamber 17 from whence the combustible mixture will pass to main burner 16. After main burner 16 is placed in operat-ion, valve 38a may be closed by turning the wheel 39 to place burner 25 out of operation. Also, if desired, valve 27 may also be closed, although this is not necessary. It will, of course, be seen that the opening in plug 35 will be kept clear at all times, due to the movement of the needle 380 through this opening.

lVhen the valve 38a is first opened for the initial starting of the burner 25 by turning the wheel 39 about half a turn, (valve 2T being considered to be opened) a small quantity of liquid fuel will be first discharged from the vaporizing tube 256 into the burner 25 before the combustible mixture of air and liquid fuel supplied for instant lighting is discharged from the vaporizing tube. This discharge of a small quantity of liquid fuel is due to the fact that when the valve 38a is first opened, quite a large quantity of liquid fuel will stand in the tube 33 and this liquid fuel must move upwardly out of the tube 33 beforethe compressed air charged with liquid fuel is supplied to the vaporizing tube 256. This liquid fuel initially discharged from the vaporizing tube 255 will be caught and held in a small recess formed in the burner 25 immediately below the outlet 250 where the liquid fuel will gradually be heated and vaporized when the burner is lit.

In Fig. 5, a modified form of the invention is shown in which a plug 42 is threaded into the bottom of the tube 33, the opening in plug 42 being tapered at its lower portion. Plug 42 has a cylindrical opening at its lower end in which is seated a semi-spherical screen 43,'the same being held in place by a small ring 44 pressed into member 42. The stem 38 has its lower end portion projecting into the opening 42a in plug 42 and it has the reduced portion 380 adapted to extend through the opening 42a.. The operation of the device shown in Fig. 5 is similar to that already described and this operationneed not be further repeated.

From the above description, it is seen that applicants have provided a very simple and efficient instant lighter structure for hydrocarbon burning devices, such as stoves, lanterns, irons, heaters etc. Although the nection with a stove, its application to other devices than stoves utilizing a hydrocarbon fuel which is vaporized before being burned, is deemed obvious. It will be understood, that if desired, the burner 25 can be used as the main burner for the hydrocarbon burning device or that if desired, thc vaporizing Atube 25?) can be connected with any suitable type of mixing chambefand burner. lVith the starting structure described, used in connection with a burner, such as the burner 25, or any other suitable type of burner, it is unnecessary to preheat t-he vaporizing tube by use of a priming cup or by a torch before the burner is lit and yet the burner can be 1naintained in constant operation after being lit without rapidly depleting the compressed air in the tank supplying the burner. The starter structure has been amply demonstrated in actual practice, and has been found to be successful and efficient.

It will, of course, be understood that various changes may be made in the form, de-y tails, arrangement and proportions of the parts without departing from the scope of applicants invention, which generally stated, consists in a device capable of carrying out the objects' above set forth and in the novel parts and novel combinations of parts disclosed and defined in the appended claims.

What is claimed is 1. The combination with a device using liquid vaporizing fuel having one or more main burners, a fuel tank adapted to contain fuel under air pressure and a Vaporizing member connecting said fuel tank and burners, of an auxiliary burner for heating said vaporizing member, a conduit connecting said auxiliary burner and the top of said fuel tank, comprising al tube extending downwardly into the liquid fuel space in said tank and having a small opening at its lower end for communication with said fuel, a second tube surrounding said first mentioned tube and forming therewith an annular space, the upper end of said annular space being open and disposed in the air space in said fuel tank and the lower end of said annular space being closed, said annular space communicating with the interior of the first mentioned tube near the lower end thereof, and a valve for controlling said first mentioned tube.

2. The combination with a device using liquid vaporizing fuel having one or more main burners, a fuel tank adapted to contain fuel under air pressure, and a Vaporizrlighter structure has been described in coning member connecting said fuel `tank and burners, of an auxiliary burner for heating adapted to extend through said opening at the bottom of said tube and a second tube surrounding said first mentioned tube and forming therewith an annular space, the upper end of said annular space being open and disposed in the air space in said fuel tank and the lower end of said annular space being closed, said annular space communicating with the interior of the first ment-ioned tube near the lower end thereof.

3. The combination with a device using liquid vaporizing fuel having one or more main burners, a fuel tank adapted to contain fuel under air pressure and a vaporizing member` connecting said fuel tank and burners7 of an auxiliary burner for heating said vaporizing member, a conduit extending from said auxiliary burner, a valve fixture connecte ed to the top lof said fueltank to which said conduit is connected, a tube secured to said xture and extending down into the fuel space in said tank, a member secured to the lower end of said tube having a small opening therethrough, a shell surrounding said member having a screen giving access to said member and opening, a second tube surrounding said first mentioned tube and forming therewith an annular space, the upper end of said annular space being open and disposed in the air space in said fuel tank, and the lower end of said annular space being closed, said annular space communicating with the interior of the first mentioned tube near the lower end thereof, a valve in said valve body having a stem extending downwardly through said first mentioned tube and the member at the lower end thereof, and having a reduced portion extending into the opening in said member.

4. ln a device using liquid vaporizing fuel and having a fuel tank adapted to contain liquid fuel under air pressure, a vaporizing member and a burner for heating said vaporizing member, a valve member, a conduit connected to said burner and to said valve member, a tube extending from said valve member downwardly into the fuel space in said tank and having an inlet opening adjacent its lower end for fuel to enter the same, said valve member being adapted to close and open communication between said tube and conduit, a second tube surrounding said first mentioned tube and forming therewith an annular space, the upper end of vsaid annular space being open and being disposed in the air space in said fuel tank, and the lower end of said annular space being closed, said annular space communicating with the interior of the first mentioned tube near the lower end thereof, whereby a mixture of air and vaporizing fuel may pass through said iirst mentioned tube and conduit to said burner from said tank.

5. In a device using liquid vaporizing lfuel and having a fuel tank adapted to contain fuel under air pressure, a vaporizing member and aburner for heating said vaporizing member, avalvemembersecuredto said tank, a conduit connected tol said valvemember and extending to said burner, a tube connected to said valve member and extending downwardly into the fuel space in said tank and having an opening at its lower end for communication with the fuel in said tank, a valve in said valve member for opening and closing communication between said tube and conduit, and having a stem projecting downwardly into said tube having a portion adapted to move through the opening in the lower end of said tube to clear the same, a second tube surrounding said first mentioned tube and forming therewith l an annular space, the upper end of said annular Space being open and disposed in the air space in said fuel tank, and the lower'end of said annular space being closed, said annular space communicating with the interior of the first mentioned tube near the lower end thereof, whereby a mixture of fuel and air may pass through `said tube and conduit to said burner. h

6. A fuel supply device for the starter of a liquid fuel stove, ysaid device comprising a valve fitting adapted to be mounted in the top of a liquid fuel tank, a tube connected to and extending downwardly from said fitting, ysaid tube having a transverse opening therein near its lower end', a sleeve surrounding said tube in spaced relation thereto and joined to said tube below said opening, said sleeve terminating short of the upper end of the tube, and means forming a restricted aperture at the lower end of said tube through which liquid may pass slowly into said tube and sleeve.

7. In a device using liquid vaporizing fuel, a fuel tank adapted to contain liquid fuel under air pressure, a burner, a vaporizing member supplying said burner and on which said burner plays when in operation, a tube running into the liquid fuel space of said tank and having an opening located in said'fuel space, means sealed from the liquid fuel space of said tank and affording communication between the air space of said tank and said tube adjacent said opening, means aording communication between said tube and said vaporizing member and means controllable from outside said tank for restricting the lll@ passage through said opening and for suddenly enlarging the passage therethrough.

8. In a device using liquid vaporizing fuel, a fuel tank adapted to contain liquid fuel under air pressure, a burner, a vaporizing member supplying said burner and on which said burner plays when in operation, a tube running into the liquid Jfuel space of said tank and having an opening located in said fuel space, means sealed from the liquid fuel space of said tank and aii'ording communication between the air space of said tank and said tube adjacent said opening, means afording commnication between said tube and said vaporizing member, a Valve controlling the passage through said tube, and means operable With said valve for restricting the passage through said opening when said valve is opened but slightly and for suddenly enlarging the passage through said opening when said valve is Widely opened.

In testimony whereof We almx our signatures.

WALTER OLSEN. SOPHUS RASMUSSEN.

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