US2038031A - Oil carburetor - Google Patents

Description

P. D, DOYLE OIL CARBURETOR Filed Nov. 29, 1933 2 Sheets-Sheet l zmwm P.D.DOYLE OIL CARBURETOR Filed Nov. 29, 1933 Apwil 211 1193569 2 Sheets-Sheet 2 Patented Apr. 21, 1936 UNETED STATES FATENT OFFICE OIL CARBURETOR Application November 29, 1933, Serial No. 700,244

4 Claims.

My invention relates to internal combustion engines, and more particularly to an auxiliary fuel supply device adapted for use with that type of engine which has positive firing mechanism such as conventional spark plug ignition equipment. This type of engine is normally suited to burn only an explosive mixture of air and gasoline or some other light combustible fluid.

My invention is designed to enable an engine of this type to employ a heavy oil combined with air to form the explosive mixture. It is my purpose, therefore, to increase the efficiency of such an engine and decrease its operating cost, without changing the fundamental construction and operation thereof, by reason of employing a fuel such as Diesel oil, which is comparatively inexpensive, but which gives greater power than the lighter oils, such as gasoline and distillate, for example.

Heretofore it has not been considered feasible to employ Diesel oil in an engine of the type dedescribed because, in the first place, it has been difficult to make an air stream pick up sufficient of the heavy oil to form an explosive mixture, and even if a suflicient amount of such oil was picked up it was not atomized sufficiently to produce a uniform mixture, and because of its low volatility, high specific gravity, and incomplete atomization it has been prone to be deposited in the passage leading to the intake manifold as condensate instead of remaining in suspension to produce an efiicient explosive mixture.

It is my main purpose, therefore, to provide a carburetion system for heavy oil in which an air flow is produced capable of picking up a sufficient quantity of the heavy oil to produce a properly proportioned explosive mixture.

It is a further object of my invention to provide a mechanism which will insure atomization of the oil to an extent that the mixture leaving the carburetor will be substantially homogeneous in character.

Still a further object of my invention is to provide means for insuring that the homogeneous mixture thus formed will remain in a suspended state during its passage from the carburetor to the intake manifold, and without allowing any condensation of the oil before the mixture reaches the cylinders, and thereafter, and to stabilize the homogeneous mixture as formed.

Another object of my invention is to provide means for mixing a regulated amount of water with the explosive mixture to increase its working efficiency.

Other objects, and more particularly those resulting from the embodiment of my invention illustrated, will be set forth in the following description of the construction and operation of my device, and in the claims, and will be found by study of the accompanying drawings.

I have shown and described only one form of my device, but I am well aware that various changes may be made by those skilled in the art, without departing from the spirit of my invention, so that although I have shown, in the con- 10 struction and arrangement of parts illustrated, the form now preferred by me, I do not wish to be limited to this embodiment alone.

Figure 1 is a side elevation of a typical internal combustion engine, showing my invention applied thereto.

Figure 2 is a longitudinal section through my device.

Figure 3 is a detail section of a part of the carburetor assembly.

Figure 4 is a top plan view of the heater, forming the lower part of the device shown in Fi ure 2.

From the conventional gasoline carburetor I a conduit l l leads to the intake manifold l9, and a branch conduit l2 connects to the discharge side of my oil supply mechanism. A butterfly valve I3, regulating the supply of gasoline mixture flowing to the engine, is normally closed, as shown in Figure 2, during the time when my oil supply mechanism is in operation, although for starting it is necessary to employ the gasoline carburetion system.

The oil supply mechanism may include a conventional float chamber 2 for oil, and a similar chamber 3 for water. Passages 20 and 30 controlled by needle valves 2l and 3i lead from the oil float chamber and water float chamber, respectively, into an atomizing device, herein shown in the form of a ball 4, disposed in the Venturi throat 50 of the air intake conduit 5. A passage 4|] disposed lengthwise of the air conduit, passing through the ball 4 and having an enlarged discharge end 4! communicates with passages 20 and 30. A throttle butterfly valve 5| for the oil supply device is located at the discharge side of the Venturi throat.

A number of tubes 60, of high heat conducting material such as copper, disposed in a casing 6,; communicate between the oil-water carburetor and the conduit l2 leading to the intake manifold. Connected to the chamber 6 is the exhaust intake 6!, leading from the exhaust manifold 69, and an outlet 62. A second wall 63 surrounds the wall of the chamber 6, thus providing an air space 64 open at the bottom and closed at the top. This air space serves to insulate the chamber from loss of heat as well as to heat the air passing therethrough, which air is delivered, preheated, to the air intake conduit 5, previously referred to.

To start the engine, the butterfly valve is left closed, and the valve I3 is opened to permit a gasoline mixture to flow into the engine. Soon the exhaust gases passing through the intake 6| and outlet 62 heat the chamber 6. At this time the butterfly valve 5| may be opened somewhat, whereupon air in the space 64, heated by contact with the walls of the chamber 6, flows first upward and then downward through the conduit 5 and into the Venturi throat 59. The needle valves 2| and 3| having been previously regulated to adjust the flow of oil and water respectively through the conduits and 30, air flowing through the Venturi throat draws oil and water from the discharge opening 4! in the ball 4. The ball, it will be noted, is disposed slightly below the throat of the Venturi throat 50. Air passing through the Venturi throat attains a very high velocity, and the shape and location of the ball serve to cooperate with this air stream to produce an annular Venturi passage between the walls of the throat 50 and the ball 4, which further increases the velocity of the air stream. This abnormally high velocity, producing a corresponding low pressure, induces a sufficient flow of the heavy oil and water from the two passages to form a good explosive mixture. Air passing at a high velocity through the small passage 4i! and into the flaring mouth 4| tends to disperse the oil and water and to distribute the same uniformly throughout the air flow as minutely atomized particles. to produce a homogeneous mixture. This mixture, passing the valve 5| and entering the tubes 66, which are preferably made of a material, such as copper, which has a high heat conductivity, is thoroughly and immediately heated by the exhaust gases passing through the chamber 6. The explosive mixture is thus first atomized and then somewhat vaporized, and

7 is heated sufficiently to eliminate any danger of the oil being deposited out of the mixture when passing through the conduit and before reaching the engine cylinders. The mixture leaving the heater in an installation of the mechanism was found to be approximately 350 F.

When the engine commences to operate satisfactorily on the explosive oil mixture the butterfly valve 5| may gradually be opened wider, and the valve l3 closed more and more, until the gasoline mixture is entirely out off, and the engine is operating solely on the heavy oil mixture. After this time the valve 5| may be operated as a throttle to increase or decrease the speed of the engine at will.

The flared opening 4| preferably terminates in a knife edge, and the air streams, one flowing outside the ball 4 and the other through the aperture 40, each following its restraining wall, meet at an angle at the edge 4|, thus producing one current of air flowing toward the center of the Venturi throat and another toward the periphery. The water, tending to wet the sides of the opening 4| and underlie the oil, assists in forming an oil film distributed over the entire area of the flared opening. Furthermore, as the oil moves outward along the wall, the increase in area effected by the flare of the opening, increases the area of the film so that it has become very attenuated upon reaching the knife edge at the mouth of the opening, and may readily be released as minute particles. The crossing air currents at the knife edge seize this oil film, break it up into finely comminuted particles and disperse them throughout the air stream.

The proportion of one part of water to twenty parts of oil by volume has been found to be satisfactory. The water vapor in the explosive mixture seems to retard the formation of carbon in the heater tubes and engine cylinders, and such negligible amount of carbon as is found is light and. fluffy, instead of the hard caked carbon usually formed.

The casing 6 also serves to mufiie the exhaust noise of the engine owing to the interference and turbulence set, up in the flow of the exhaust gases by the pipes 60 interposed between the passages 6| and 62.

What I claim as my invention is:

1. A fuel oil supply device for internal combustion engines comprising fuel atomizing means, a conduit connected to the intake manifold, and a heater interposed between said fuel atomizing means and said conduit comprising a plurality of copper tubes through which the explosive mixture passes, a casing surrounding said tubes, an engine exhaust conduit connected to said casing to heat the same by means of hot exhaust gases, a wall surrounding said casing to form an air chamber open at the bottom and closed at the top, and a conduit connecting such air chamber to the fuel atomizing means.

2. In an internal combustion engine, in combination, an air intake conduit, means in said conduit to atomize and deliver a heavy oil and water mixture to an air stream therethrough, an intake manifold, a heater interposed between said air intake conduit and said manifold, a second air intake conduit connected directly to said manifold, means in said second air intake conduit to atomize and deliver gasoline to an air stream therethrough, and separate means in each air intake conduit to control flow of air through the respective conduits.

3. A fuel oil carburetor for internal combustion engines comprising an air intake conduit having a Venturi throat therein, a ball positioned in and spaced from the wall of said throat to form therewith an annular Venturi passage between said ball and the throat, an oil delivery pipe and a water delivery pipe connected to said ball and opening into a common chamber formed therein, and said ball having a flared opening from said common chamber in its side toward the discharge end of said Venturi throat to effect blending and atomizing of the water and oil flowing from said ball.

4. A fuel supply device for internal combustion engines comprising an air intake conduit formed with a Venturi throat, a ball positioned in and spaced from the wall of said throat to form therewith an annular Venturi passage between said ball and the throat, said ball having a passage therethrough coaxial with said conduit, the discharge end thereof being flared to form at the surface of said ball a sharp circular edge, a fuel delivery pipe communicating with said passage to feed fuel for distribution over the surface of the flared discharge opening down to said sharp edge, whereby air flowing around said ball and through said passage therein sweeps along both faces H forming said sharp edge, converging to form a single air stream beyond said edge, and picks up fuel therefrom and atomizes it in its passage.

PALMER D. DOYLE.

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