US2384609A - Fuel carburation system - Google Patents

Description

Sept. 11, 1945. R F. DEN/R155 2,384,609

FUEL CARBURAT ION SYSTEM Filed Feb. 19, 1945 I@ um IN VENTOR.

y ATTORNEY.

Patented Sept. 11, 1945 UNITED STATES l-jATENT OFFICE FUEL CARBURATION SYSTEM Reinier P. De Vries, Melrose, Mass.

1 Claim.

The invention has for another object to pro-..

vide a fuel carburation system including a novel heavy fuel vaporizer wherein hot air is passed through a body of heavy fuel liquid with vaporizing effect thereupon, means being provided to automatically regulate and control the air temperature to maintain the same at a predetermined required degree, and means being further provided to regulate the volume or head of the heavy fuel liquid, whereby to predetermine the time of contact of the hot air and liquid fuel, to the end that a uniformly stable and correctly proportioned air and fuel vapor mixture is produced and served to the engine cylinders, adequate for efficient operation of the engine at all speeds and loads, l

The invention has for another object to provide a heavy fuel vaporizer as above characterized, the construction of which provides novel means for distributively discharging hot air into and for passage through the heavy fuel liquid, and which further provides a novel means for thoroughly mixing and drying the air-vapor mixture prior to delivery thereof to the engine cylinders.

And still further objects of the invention are to provide means for utilizing the waste heat of the engine exhaust gases for heating the air served to the heavy fuel vaporizer, and to provide means for manually controlling the system for shifting from service of an. initial gasoline fuel mixture to that of the heavy fuel vapor mixture.

Other objects of this invention, not at this time more particularly enumerated, will be understood from the following description of the same.

The accompanying drawing provides a schematic view of the novel multi-fuel carburation system of this invention, certain parts being shown in section.

In the drawing, the reference character I indicates a fuel mixture intake manifold of an internal combustion engine, and 2 indicates the exhaust manifold of said engine.

Connected for communication with said intake manifold I is an ordinary carbureter 3 for producing a gasoline fuel mixture; the air intake of said carbureter 3 being equipped with a suitable air cleansing lter 4, in the well known manner.

Application February 19, 1943, Serial No. 476,391

Mounted within the fuel mixture discharge portion 5 of the carbureter 3 is the usual throttle valve 6, which is subject to optional manipulation by either the hand control 'I or the foot control 8.

The heavy fuel vaporizer of the system comprises a vaporizing chamber 9, preferably provided with a dish-shaped bottom end wall I0,

and having an upwardly open top end. The selected relatively heavy liquid fuel is delivered into the bottom end of said vaporizing chamber 9 througha float chamberl I I, which is connected with a source of liquid fuel supply (not shown), so as to receive the same therefrom. The liquid fuel is delivered-from said float chamber Il to said vaporizing chamber 9 through an intercommunicating flexible conduit I2. The float chamber operates to automatically maintain the liquid fuel within the vaporizing chamber at a predetermined level. The oat chamber II is so arranged and mounted relative tothe vaporizing chamber that it may be adjustably raised or wlowered to vary the level of liquid fuel Within the latter, whereby to regulatably increase ordecrease the volume or head of liquid fuel therein, for the purposes and with the advantages hereinafter more particularly explained; and to this end, said oat chamber II is carried on a vertically adjustable support, comprising e. vg. a screwthreaded suspension rod I3 which extends through an external supporting bracket I4 affixed to said vaporizing chamber, and said rod having upper and lower adjusting nuts I5 and I6, manipulation of which permits vertical adjustment of said float chamber for disposition thereof relative to the vaporizing chamber in a selected liquid fuel level determining position. The connection for coupling said conduit I2 to the bottom of the vaporizing chamber preferably includes a normally closed drain means I'I. 1

Extending over the upper open end of said vaporizing chamber 9 is a diametrically enlarged hood I8, the dependent skirt flange I9 of which overlaps the upper end portion of said vaporizing chamber in concentrically spaced relation thereto, thus providing an annular vapor discharge passage 20. Intersecting said vapor discharge passage 20 are a series of circumferentially spaced oblique vanes 2l, which impart a swirling movement to the air and vapor mixture discharging from the vaporizing chamber, whereby to effect turbulence thereof operative to thoroughly mix the air and vapor constituents of the mixture. Surrounding the thus hooded end of the vaporizing chamber is a closed diametrically enlarged fuel mixture collecting and drying chamber 22.

In order to balance the pressure within the oat Y chamber Il with that within the vaporizer, a exible conduit 23 is communicatingly connected between the interior of said collecting and drying collecting and drying chamber.

The means for delivering hot air to the vaporizing chamber 9, in a preferred arrangement.

thereof, comprises an air heater 24, the interior of which is suitably partitioned to provide an exhaust gas chamber or compartment 25 and a fresh air chamber or compartment 26. Said heater is provided with an exhaust ga intake 21 adapted to be communioatingly con ected with the exhaust manifold 2 of an internal combustion engine, to deliver hot exhaust gases into said exhaust gas chamber or compartment 25, and an exhaust gas outlet 28 to discharge exhaust gases from the latter to the atmosphere through an exhaust pipe 29. Said heater is further provided with an air intake 30 leading into the air chamber or compartment 26, and an air outlet 3| discharging from the latter. Fresh atmospheric air is delivered to the air chamber or compartment 26 of the heater 24 through a cold air delivery conduit 32, which preferably communicates with the atmosphere through an attached air cleansing iilter33. Cold air delivered into the heater 24 is heated, and the resultant hot air is discharged througha hot air delivery conduit 34, which extends to and is coupled with a hot air discharge manifold 35 entered in the vaporizing chamber 9. As a safety factor, the line of said hot air delivery conduit 34 may include, if desired, a spark arrester means 36 of suitable construction.

Means is provided for both modifying the temperature of the hot air delivered into the vaporizer and automatically maintaining the same at a selected temperature suitable for vaporization of a given grade of liquid fuel desired to be vaporized within the vaporizer. To this end a cold air by-pass conduit 31 extends from the main cold air delivery conduit 32 to communicate with the hot air conduit 34, in advance of the point of connection of the latter with the vaporizer hot air discharge manifold 35. Included in the line of said cold air by-pass conduit 31 is a temperature control valve 38 adapted to be actuated by means which is responsive to the temperature of the hot air flowing to the vaporizer through said hot air conduit 34, as

e. g. by a trapped expansible gas confined in a gas bulb 39 which is exposed to contact by the hot air traversing said hot air conduit 34. Said bulb is connected, though pipe 40, in communication with ari-adjustable spring contracted bellows 4l, expansion of which opens the valve 38, and contraction of which closes said valve, through interconnecting linkage 42. An adjustable thrust nut 43, or other suitable means, is provided for regulating the tension of the bellows contracting spring 44, whereby to adjust the temperature control valve mechanism, so as to obtain operative response thereof to a desired selected temperature, as will be hereinafter explained. In order to visibly indicate the temperature of the hot air which is 'delivered to the vaporizer chamber 9 through the manifold 35, a thermometer 45 may be provided, the same being operatively connected to a thermometer bulb 46 which is exposed to contact by the hotair entering said manifold 35.

The hot air discharge manifold 35, which serves the vaporizer, extends axially downward through the collecting and drying chamber 22,

hood I8, and into the interior of the vaporizer chamber 9. At its lower end said manifold 3l is provided with a plurality of radial discharge arms 41, the lower ends of which terminate in inwardly directed nozzleA members 48, which are closely spaced in substantially parallel relation to the bottom end wall I0 of the vaporizer chamber 9. These nozzle members 48 are provided, on their underside and along the lengths thereof, with a multiplicity of small discharge outlets 49. Said nozzle members 48 being submerged in and at the bottom of the body of liquid fuel supplied to the vaporizer chamber 8, function to distributively discharge hot air into said fuel body, so that the hot air will divide into a multiplicity of small streams' adapted to bubble upwardly through said liquid fuel with vaporlzing eiect thereupon. Arranged within the vaporizing chamber 9, above the level of the liquid fuel body contained therein, is a transverse perforate anti-splash plate 59, or equivalent pervious body, which not only arrests undue splashing or violent movement of the liquid fuel (especially when the system is used in connection with the internal combustion engine of an automotive vehicle), but also serves to further break up or more finely subdivide the air and vapor bubbles discharged into and through the upper regions of the vaporizing chamber 9.

The air-vapor mixture generated within the vaporizer is discharged therefrom through a. fuel mixture delivery conduit 5I, which leads out of the top of the collecting and drying chamber 22, and extends to a coupling connection 52 which communicates with the engine intake manifold I, at a point between the latter and the discharge portion 5 of the gasolene carbureter 3. Mounted within said coupling connection 52 is a second throttle valve 53, which is subject 'to optional manipulation by either the hand control 54 or the foot control 55. I

Means is provided for testing the heavy fuel air-vapor mixture, the same comprising a shunt conduit 56A connected in communication between the hot air delivery conduit 34 and the fuel mixture delivery conduit 5I, so as to by-pass the vaporizer. Arranged in the line of said shunt conduit 56 is a manually actuatable normally closed valve 51. 'I'he manner of using this testing means will be subsequently explained.

In order to prevent loss of heat by radiation from the vaporizer, it is desirable to cover the collecting and mixing chamber 22 and the vaporizing chamber 9 thereof with an insulating jacket (not shown), such e. g. as an asbestos jacket or other suitable insulating material. The heater 24 and any other parts of the system desired'to be protected from heat losses by radiation may be likewise insulated.

In the use and operation of the system, when starting, from cold condition, an internal combustion engine served thereby, the throttle valve 53 isclosed, and the throttle valve 8 is opened to admit a gasolene fuel mixture to the engine intake manifold I, whereby to start and warm up the engine with such4 readily volatile fuel. After an initial period of engine operation under such conditions, suiiiciently long to produce effective operation of the heater 24 by engine exhaust gases, the throttle 53 is partly opened, thereby admitting excess air to the gasolene mixture, to induce circulation of air through the vaporizer, whereupon cold air is delivered through the cold air delivery conduit 32`to said heater 24. As the cold air passes through the heater 24, its tem- .4| against extension u the valve 38.

perature is considerably elevated, and it flows onward, as a hot air stream, from the heater through the hot air delivery conduit 34 to the\ vaporizer manifold 35 to issue from the nozzle members 48 thereof, so as to bubble upwardly through the liquid fuel content of the vaporizing chamber 9 with vaporizing effect thereupon, whereby to generate a combustible or explosive air-vapor mixture for delivery through the fuel mixture delivery conduit 5l and intake manifold I to the engine cylinders.

As soon as the vaporizing equipment is warmed up, and properly proportioned air-'vapor mixture obtained, the engine will increase in speed, whereupon the throttle valve E is fully closed to shut off the gasolene fuel mixture, and thereafter the throttle valve 53 may be manipulated so as t0 controllably operate the engine solely by the delivered air-vapor mixturel produced in and supplied from the vaporizing chamber 9 A mixture of just the right amount of air and fuel vapor is obtained, according to the grade of liquid fuel used, by adjusting the level or head of liquid fuel in the vaporizing'chamber 9, and by regulating and maintaining the temperature of the hot air delivered to and through said liquid fuel at a predetermined degree best adapted.; for vaporization of the selected grade of the latter. For instance, when dealing with kerosene as the ,selected liquid fuel, as compared with heavier,-

grades of fuel, such e. g.- as light fuel oils, the head of liquid fuel in thewaporizing chamber 9 may be lowered, and the temperatureA of the hot air reduced, sinceless .timejoffcontactfof the air with such liquid fuel and a' lowe'te'r'np'erature would be adequate to produce the required 0perative air-vapor mixture. With grades of fuel tion of the thermometer 45 will visibly advise as to thel temperature of the hot air entering the vaporizing chamber 9. Proper adjustment of liquid fuel level or head and proper regulation of the temperature of the hot air delivered into the vaporizing chamber will assure a proper combustible or explosive air-vapor mixture for env gine operation at all speeds, without necessity for supplying additional air to such produced fuel mixture.

Testof the efficiency of the air-vapor mixture delivered to the engine may be made by opening the manual valve 51 to allow heated air to be drawn into the air-vapor mixture. Assuming that the temperature of the hot air has been modified and held to a proper, degree suitable to the particular grade of liquid fuel in use. if, upon admitting additional heated air into the airvapor mixture, the engine speeds up, this indicates that the mixture is too rich, correction of which may be made by closing `the valve 51 and then lowering the level or heady of liquid fuel in the vaporizing chamber 9 soas to suitably lean the mixture. Y i' Having now described my invention, I claim: A liquid fuel vaporizer .apparatusjcomprismg a l vaporizingr chamber having-aaclosedbottom and oil heavier than kerosene, the level Lor headof liquid fuel in the vaporizing chamber should be raised to give longer contact of hotair with said liquid fuel as it bubbles therethrough, and .at the 1 y trol of the temperature of the hot air delivered` an open top and adapted toicon'tain a volume of a selected volatizable liquidfuel, means to deliver hot air for passage kinto and upwardly through the liquid fuel contained in said lvaporiztion thereto whereby to provide a downwardly open gaseous mixture discharge passage leading fout of said vaporizing chamber, oblique varies intersecting said discharge passage operative to"l impart. swirling movement to the gaseous mix- "ture outgoing therethrough, a closed diametrcallyl enlarged annular collection and drying chamber surrounding said hood and the upper end-tof 45- said -vaporilting chamber in concentrlcally` spaced relatiorithereto adapted to receive the discharged gaseous mixture; a fuel mixture delivery conduit leading away from said collection and drying chambenmeans to deliver liquid fuel to said vae,

porizingv chamber including a float control1ed valve chamber disposed exteriorly of the vapor-"f`A izing chamber. a. conduit in communication with and between the bottom interior of said drying and collection chamber and the interior of said to the vaporizi g chamber is accomplished -by admitting to the hot airstream by operation of the temperature control val'vcs, a controlled or measured amount of cold air suillcientto/reduce lthe temperatureof the air, ultimately vdelivered to the vaporizing chamber 9, to lthe desired degree. To thus modify and control the' hot air ,y temperature, the bellows contracting pressure of the spring 44 is adjusted so as to hold the bellows, expansion of the fluid in the communi/cath@ bulb 39 and bellows 4| by rise of temperature of the hot air in contact with the former, beyond a desired predetermined degree, overcomes the spring resistance, and thereby allows the bellows to extend and open Opening of the valve 38 admits sufficient cold air for admixture to the hot air stream as will drop and hold the temperature of the latter to the desired degree. It will be obvious that this operation, once the bellows spring adjustment is made, will be automatic. Inspecfioat controlled valve chamber, whereby to balance the pressure within the latter chamber with that within the vaporizer chamber and to addiuonauy srve to drain back to said float controlled valve chamber any liquid fuel condensation accumulating in said drying and collection chamber, means to control the te perature of hot air delivered through the liquid uel within the vapcrizing chamber and the time of contact of said air with said liquid fuel to, that best adapted for vaporizing a selected given gradeoi liquid fuel, said means comprising means to automatically regulate the temperature of said hot air, and means to mount said float controlled REINIER P. DE VRIES.

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