US2056334A - Carburetor - Google Patents

Description

Oct.. 6, 1936.

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' E. D. WALLACE CARBURETOR Filed Oct. 19, l1964 E; EDWaliace 2 Sheets-Sheet l Gttomeg Oct. 6, 1936.

E. D. WALLACE CARBURETOR v 2 .SheeJcS-Sheet 2 Filed Oct. 19, 1934 Fig. 3 l

` 3nventor.,

Ellwallace i mg. W (lttorneg Patented Oct. 6, 1936 UNITED STATES PATENT oFFlcE CARBURETOR Application October 19, 1934, Serial No. 749,118

5 Claims.

The present invention relates to carburetors for internal combustion engines and thelike, and has for an object to provide an improved structure for more effectively completing the volatilization of the fuel, such as raw gasoline so as toprovide a better vaporized mix of the hydrocar- 4bon and air than with present used devices.

Another object of the invention is to provide a device of this character which may be used on different types of internal combustion engines and alsowith varioustypes of liquid fuels so as to obtain the best possible results from the -fuels and in the din'erent'types of engines.

The invention has for a further object the provision of an improvedl means for initially` heating and'vaporizing the liquid" fuel prior to its admixture with` the main body of air and prior to its delivery to the intake manifold of the engine, andto provide various means for controllingthe vaporization of the fuel and the quantity thereof for admixture with theair.

With the foregoing and-,other objects in View, the inventionV will be more fully described lhereinafter, and will be more particularly pointedr out in the claims appended hereto.

In the drawings, ,wherein like symbols refer to like or corresponding parts throughout the severalviews,

Figure l'is an enlarged vertical ysectional view taken through a carburetor constructed Vaccord-r ing to the present invention, the section being taken substantiallyon the line I -I of Figure 3.

Figure 2 is .a horizontal section taken through the carburetor on the line 2-2 of Figure 1, and

Figure is a top plan viewl of the device.

Referring now to the drawings, I0 designates the body of the carburetor which may be in tubular or type form and comprises the body part of vthedevice. As shown, the bodyv part I8 may be arranged with its axis .in vertical position and provided at its lower end with a flange II for attachment to the intake manifold of an internal combustion engine. A throttle valve I2, of the butterfly type, may be disposed in the lower end of the tubular body II) for controlling the passage of thekmixture to the manifold in the ordinary manner.

The upper end of the tubular body I0 may be connected to an air supply pipe I 3-which may lead from an air cleaner or the like and which is preferably connected to the body I 0-by a bell and spigot connection as shown providing a seating shoulder I4 upon which is supported a passage reduction disc I5 having a central opening I6 of reduced diameter as compared to that of the feed pipe I3 and the body I Il. The disc I5 is adapted to stabilize the flow of air downwardly through the tubular body I0. A screen I1 may be disposed upon the shoulder I4 beneath the disc I5for the purpose of intercepting the passage of dust and other foreign particles into the body II) of the carburetor.

At one side of the body I0, the carburetor is provided with the usual bowl or container I8 of suitable size to receive a desired quantity of the liquid fuel to be used. The bowl I8 is provided' in its bottom with ar suitable drain plug I9 by means of whichxsediment collecting in the bottom of the bowl may be removed from time to time. The liquid fuel is fed through the top of the bowl I8 by a suitable pipe connection 20 which opens downwardly through the top of the bowl and is providedwith a downwardly facing valve seat 2| against'which aneedle valve 22 is adapted to seat when raised. The needle valve 2| bears at itslower end'upon a float 23 which is connected bya hinge 24 to one side of the bowl I8 and is adapted'to swing on the lhinge 24 when raised and lowered by changes in the surface level of the fuel in the bowl. Thus, the ioat 25 and valve 22` maintain a predetermined constant surface llevel ofthe liquid fuel in thev bowl I8. The bowl I 8 may be supported upon the body Illbybracket arms 26fand 21 which extend outwardly from the body IIJ and engage the upper and lower portions of the bowl.

vDisposed at preferably the opposite side of the body portion I0 vis a vapor forming chamber 28 which is connected by a pipe 29 to the bowl I8. The pipe 29 opens into the bowl at a point below the normal surface level ofthe liquid fuel and opens into the lower portion of the chamber 28 so as to maintain in the lower portionY of the chamber a surface level of the liquid fuel equal to that in the bowl I8.

Thus, a small quantity of the liquid fuel is maintained in the chamber 28 lin the lower end thereof, and the upper end of the chamber is left free for the accumulation of vapor from the liquid fuel. Extending axially through the chamber 28 is a tube 30 which is provided in one side with an opening 3I leading to the interior ofthe chamber 28 at a point below its normal surface level of liquid so that the liquid fuel may pass into the tube 30. A closed tube 32 is connected to the tube 3i]V at its lower end and extends a suitable distance to the exhaust manifold 33 cf an internal combustion engine, the tube 32 being closedA at its lower end andbeing externally threaded vfor adjustable engagement through the wall of the exhaust manifold or pipe. Thus, the lower closed end of the tube 32 may be heated by the exhaust gases passing through the pipe 33, or any other suitable heating means may be provided for the tube 33.

The upper end of the tube 30 is connected to a valve casing 34 which carries an adjustable valve 35 adapted to seat against the upper end of the tube 30 to close it, and which may be set to maintain an opening of desired size at the top of the tube. A vapor nozzle 36 is connected to the valve casing 34 beyond the Valve 35 and projects through the adjacent wall of the tubular body Il) and is provided with a relatively long end 31 bent at an angle to the body of the nozzle 36 and which extends toward the lower outlet end of the tubular body and is open at its end.

For the purpose of admitting a small amount of air to the upper portion of the tube 30, above the surface level of the liquid fuel, an air valve casing 38 is mounted in one side of the chamber 28 and opens into one side of the tube 38 at a point above the normal surf-ace level of the liquid fuel therein. The air valve casing 38 carries a controlling valve 39 which may be threaded in the casing and adjusted relatively to the valve seat of an air port 40 in the bottom of the casing 38. The tube 30 is therefore vented at its upper end so as to prevent an air lock therein incident to the accumulation of vapor in the top of the tube. It is found essential to locate the air inlet device 38 closely adjacent to but above the normal surface level of the liquid fuel in the chamber 28 so that the air admitted through the valve 38 may properly Vent the upper vapor chamber and allow the accumulating vapor to freely escape through the upper vapor valve 34.

In the operation of the carburetor, the air is drawn downwardly by the action of the internal combustion engine through the air pipe I3 and through the disc I5, the latter insuring a steady ow of air through the body I0, particularly when the engine is idling or operated at relatively slow speeds. The air passing through the disc I5 expands and travels uniformly throughout the cross sectional area of the body I0 throughout the length thereof and at all times creates the desired pressure at the open end 31 of the vapor nozzle 36.

The liquid fuel passes from the bowl I8 through the pipe 28 to the chamber 28 and maintains the desired surface level of the liquid fuel in the chamber. The liquid fuel passes through the opening 3l into the tubes 30 and 32, and when the latter is heated the heat is transmitted through the liquid fuel to the upper part of the fuel within the chamber 28 and the vapor from the liquid fuel accumulated in the upper end of the tube 30. Any vapor pressure within the upper end of the chamber 28 about the tube 30 exerts a desired pressure against the upper surface of the fuel in the chamber and consequently augments Iand assists in the ejection of the vapor upwardly through the vapor valve 34. The Vapor passes the valve 34 at the desired rate, determined by the adjustment of the valve 35, and enters the valve nozzle 36 from which it is admixed with the column of air flowing outwardly through the hollow body Ill.

The liquid fuel is thus delivered into the mixing chamber or body part I 0 in the form of a vapor which is relatively heavy and which thus readily admixes with the air before the mixture reaches the throttle valve I2. The air vent or valve 38 prevents the lifting or drawing of the liquid fuel upwardly into the vapor valve 34 but the amount of air through the valve 38 is so controlled as not to chill or otherwise destroy the effect of the relatively heavy vapor formation in the upper end of the tube.

It is of course understood that the bowl I8 as well as the chamber 28 may be connected 01' constructed otherwise than as shown, the important features being the relation of the parts to maintain the desired surface level of the liquid fuel in the chamber 28 and to feed the vapor formed by the heating of the fuel in the pipe 30 directly into the mixing chamber.

By means of this construction at no time is the unvaporized liquid fuel admitted to the mixing chamber so that a relatively uniform mixture is provided at the throttle valve and the mixture is raised to the proper working temperature by the heat of the vapor which passes through the nozzle 36. y

I do not wish to be restricted to the size, form and proportions of the various parts, and obviously changes could be made in the construction herein described without departing from the spirit of the invention, it being only necessary that such changes fall within the scope of the appended claims.

What is claimed is:-

1. A carburetor comprising a mixing chamber having a throttle valve at its lower end and an air intake at its upper end and adapted for connection with the intake manifold of an internal combustion engine, a fuel supply bowl, a vapor chamber, means connecting the supply bowl with the vapor chamber, means for maintaining a predetermined surface level of liquid fuel in the bowl and chamber, a threaded air inlet valve connected to the vapor chamber, a heating tube connected to the chamber for receiving liquid fuel therefrom and adapted at its lower end portion for insertion in the exhaust manifold of the engine for heating the fuel in the tube and chamber and vaporizing the fuel in the upper end of the tube and chamber, a vapor valve mounted 0n the upper end of the chamber for controlling the outlet of vapor therefrom, and a nozzle leading from the vapor valve and opening axially and downwardly into said mixing chamber for admixture of the vapor with air passing through the mixing chamber.

2. A carburetor comprising a, tubular body open at its upper end to receive air and adapted for connection at its lower end to the intake manifold of an internal combustion engine, a liquid fuel supply bowl disposed at one side of the tubular body for maintaining a predetermined surface level of liquid fuel in the bowl, a vaporizing chamber connected to the bowl for maintaining the said surface level of the liquid fuel in the lower end of the chamber, a threaded air inlet for said chamber, a heating tube extending from said chamber to receive liquid fuel therefrom and adapted at its lower end portion for insertion in the exhaust manifold of the engine for vaporizing the fuel for accumulation in the upper end of the chamber, a vapor nozzle connected to the upper end of the chamber for receiving the vapor therefrom and opening axially downward in the tubular body for delivering the vapor into the air stream therein and an adjustable valve for said vapor nozzle.

3. A carburetor comprising a mixing tube having a throttle valve at one end and an air intake at its opposite end, a oat chamber at one side of said mixing tube, a vaporizing chamber exteriorly of the tube and connected to the float chamber for maintaining a surface level of liquid in the vaporizing chamber equal to the surface level of the liquid in the float chamber, adjustable valve means controlling the passage of air to the vaporizing chamber, a heating tube extending downwardly from the vaporizing chamber for connection through the side of an exhaust manifold for heating fuel from the vaporizing chamber, a nozzle leading from the upper portion of the vaporizing chamber into said mixing tube and opening toward the throttle valve and a threaded needle valve contro-lling the opening in the nozzle.

4. A carburetor comprising a mixing chamber having a throttle valve at its lower end and an air intake at its upper end and adapted for connection with the intake manifold of an internal combustion engine, a fuel supply bowl, a vapor chamber, means connecting the supply bowl with the vapor chamber, means for maintaining a predetermined surface level of liquid fuel in the bowl and chamber, a threaded air inlet Valve connected to the vapor chamber, a heating tube Connected to the said vapor chamber and receiving liquid fuel therefrom, means for heating the said heating tube to vaporize the liquid fuel therein, a vapor valve mounted on the upper end of the said vapor chamber for controlling the outlet of vapor therefrom, and a nozzle leading from the vapor valve and opening axially and downwardly into said mixing chamber for admixture of the vapor with air passing through the mixing chamber.

5. A carburetor comprising a mixing chamber having a throttle Valve and an air intake in relatively spaced apart relation from the throttle and adapted for connection with the intake manifold of an internal combustion engine, a fuel supply bowl, a vapor chamber, means connecting the supply bowl With the vapor chamber, means for maintaining a predetermined surface level of liquid fuel in the bowl and chamber, adjustable intake means connected to the vapor chamber for admitting air, a heating tube connected to said Vapor chamber and receiving liquid fuel therefrom, means for heating the said heating tube to vaporize the liquid fuel therein, adjustable and outlet means disposed between the upper end of the vapor chamber and said mixing chamber for admixture of the vapor with air passing through the mixing chamber.

EARL D. WALLACE.

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