US1384799A - Carbureter - Google Patents

Description

w. E. DEWEY.

CARBURETER.

APPLICATION FILED JAN. 17. 1917.

1,3 4,799. Patented July 19,1921.

Arm/v56 PATENT OFFICE.

WILL E. DEWEY, OF ROCKFORD, ILLINOIS.

CARBURETER.

Specification of Letters Patent.

Patented July 19, 1921.

Application filed January 17, 1917. Serial No. 142,820.

ToaZZ 'w hom it may concern Be it known that I, WILL E. DEWEY, a citizen of the United States, residing at Rockford, in the county of lVinnebago and State of Illinois, have invented certain new and useful Improvements in Carbureters, of which the following is a specification.

This invention relates in general to fuel mixing devices, and has more particular reference to carbureters especially adapted for use with internal combustion engines.

It is well recognized that inefficiency and poor operation of internal combustion engines caused by improper fuel mixture is due mainly to faulty carbureter design. In the carbureter liquid fuel is volatilized by the admixture in various ways of air, the fuel being most readily ignitible and effective when most completely volatilized with the proper amount of air; and it follows that such designs as cause stratification and con densation of the fuel in the carbureter are inimical to economical and efficient operation.

The primary object, therefore, of my invention is to overcome the objectionable features of carbureters now in use and to obtain a carbureter of high efficiency by providing for the mixture of fuel and air in a novel manner that will insure thorough volatilization of the fuel with the proper amounts of air underall conditions of operation and will avoid stratification and the general consequences of condensation of the fuel.

Another important object of my invention is to provide a carbureter in which the supply of secondary or auxiliary air is automatically governed in a novel manner to completely volatilize the fuel and carry it in such condition to the engine.

In furtherance of these general objects I have provided a carbureter of generally improved construction so far as relates to the parts for mixing and conducting the fuel and air and controlling the supply of auxiliary air. A most important feature in this connection is the novel arrangement of the fuel and air conduits and the intake of the secondary or auxiliary, all of which will be fully described hereinafter. Another feature is the provision of a diffusing or distributing plate, which in conjunction with the secondary air intake, causes the primary mixture to be more fully volatilized and supplied with the proper amount of air.

A still further object of the invention is to provide an improved means for automatically controlling the supply of secondary air and also for varying such supply by means of an adjustment under control of the operator so that the best results may be obtalned under various conditions of operation.

Other objects and many of the inherent advantages of my invention will be readily appreciated by those skilled in the art as the same becomes better understood by reference to the following description when considered in connection with the accompanying drawings, wherein Figure 1 is a vertical sectional view through a carbureter embodying my improvements; and

Fig. 2 is a horizontal sectional view taken on the line 2-2 of Fig. 1:

Since my improvements have no special reference to the means for supplying and controlling the supply of liquid fuel, or to the throttle controlled outlet from the carbureter, or to the arrangement of this outlet, I have illustrated these in a somewhat conventional and brief manner. The fuel supply may be of any suitable or preferred form, and in this instance I have shown a well known form of nozzle or jet 4, communicating through passages 5 with a float chamber 6 in which the proper level of the liquid fuel supplied through the pipe 7 is maintained by a float 8 in a manner not shown but well understood in the art and forming no part of the present invention. The nozzle 1 is positioned centrally within a primary air intake casing 9 which passes through an aperture in the bottom of the float chamber casing and is interiorly threaded to receive the threaded extension 11 of the main body of the darbureter. thereby securing the float chamber housing rigidly to the main carbureter body. This body is shaped to provide a comparatively long and narrow primary air tube or conduit 12 into the lower or inlet end of which the nozzle at projects. The upper or outlet end of the primary air conduit is widened and opens into a mixing chamber 13 more fully described hereinafter, which chamber is in reality the top end of a secondary conduit 14 surrounding the primary conduit 12 and having an outlet 15 which connects with the engine manifold 16 and is equipped with a throttle valve, such for instance as an ordinary butterfly valve 17, adapted to be controlled by an operator. The terms primary conduit and secondary conduit refer .to the general conduit through which the fuel passes and distinguishes different portions of said general conduit by the air supplies. That is, the conduit through which passes the fuel laden with the primary .air is termed the primary conduit, and from the point the secondary or auxiliary air is added the conduit is spoken of generally as the secondary conduit. Fuel is drawn from the nozzle 4 by the engine suction and will pass upwardly through the primary conduit 12 into the mixing chamber 13 and will be drawn around the top end of said conduit and down through the secondary conduit to the outlet 15 and thence to the engine, as indicated by the arrows in Fig. 1. As the liquid is drawn from the nozzle 41-, the primary air drawn upwardly through the conduit 9 will be deflected to the center of the channel by the converging wall 18 so that the velocity of the air is considerably increased and the air in thus mixing with the fuel will atomize and vaporize the same. This primary mixture will be-drawn upwardly through the long narrow conduit 12, which while holding the mixture in a confined area allows it to become quite thoroughly volatilized before it is supplied with secondary of auxiliary air. In order to better vaporize the mixture during its passage through the primary conduit the latter is slightly tapered longitudinally, as shown in Fig. 1.

By means of an annular projection or diffusing plate at the outlet end of the primary conduit in conjunction with the arrangement of'the adjacent parts a conduit is formed, causing the mixture upon leaving the outlet end of the primary conduit to be distributed and'diffused radially and to pass outwardly in all directions and thence down around the peripheral edge of the plate. The conduits are so relatively proportioned as to give confined areas or passages in which it is desired to positively control the mixture and hold it, as it were, in positively defined channels, so that the secondary air may be properly mixed with the fuel in a manner that will insure thorough volatilization and will preclude stratification. The diffusing plate 19 provides an upwardly and outwardly flaring annular wall, the diameter of which is slightly greater than that of the secondary conduit 14. The passage from the outlet end of the primary conduit around the peripheral edge of the diffusing plate and into the secondary conduit is restricted and defined by the inner walls of the mixing 1 chamber casing 13 and also by a secondary and directly opposite the outlet of the primary conduit. This valve is secured to a stem 22 slidably mounted in a sleeve 23 in turn longitudinally slidable in the central spider bearing 24- of a valve seat member. 25 threaded into the top of the casing 13. Spring means are provided for-yieldingly resisting movement of the valve in an opening direction and consists of a relatively light expansion spring 26'interposed between the flange 27 of the collar'23 and a nut 28 adjustable on the upper end of the valve stem and a second expansion spring 29, preferably of greater strength than the spring 26, coiled on the valve stem and interposed between the upper end of the collar 23 and the lower end of the nut member 28, although terminating short of the nut member so as not to be normally effective. The collar 23 may be removed longitudinally upon and with respect to the valve 7 stem to' compress thev spring 26 and also to bring the spring 29 into operation, so that the yielding resistance to the opening move ment of the valve may be varied at the will of the operator. A. suitable lever under the control of the operator is provided for de-' termining the position ofthe collar 23 to regulate the supply ofsecondary air under different conditions of operation. This lever may be in the form of a bell crank 31 pivoted at 32 on one of the spider arms of the valve seat member and shaped so that the end of the bell crank is bifurcated and extends beneath the annular flange 27 of the collar 23. Any suitable connection may be attached to the end 34 of the bell crank lever for the purpose of rocking the same and holding it in any of a plurality of adjusted positions. When the lever is rocked in a clockwise direction its bifurcated end 33 will slide the collar 23 upwardly on the valve stem, thereby compressing first the spring 26 then the spring 29, the stop 35 on the lever limiting its movement by contact with the valve seat member. A. cap 36 may be mounted on the collar 23 to protect the springs and also to prevent tampering withthe adjusting nut 28, since it is intendedto properly adjust the nut when the carbureter is manufactured and to adjust the spring pressure only by means of the lever 31 or any suitable means for moving the collar 23 lengthwise. It will be noted that the valve 21 is not seated, but is suspended in a balanced position.- And since the spring 26 is thus preferably adj usted so as not to seat the valve under certain operation, the valve will be further opened by the suction of the engine, allowing a very plentiful supply of secondary air to be drawn in. This supply may bedecrea sed and varied at will by adjustment of the lever 31 and when the same is adjusted to the Y fullest extent so that the combined pressures iao of the springs 26 and 29 hold the valves seated, the admission of secondary air is shut off so that the valve serves as a choker.

Assuming that the carbureter is attached to an automobile and operated at ordinary speeds, for instance up to approximately 20 miles an hour, the valve may be set to operate in the manner shown in Fig. 1. This means that a plentiful amount of secondary air will be supplied to the fuel and by causing this air to thoroughly disintegrate and atomize the fuel, producing a fully vaporized mixture, a very effective explosive fuel will be obtained, enabling very economical consumption due to the relatively large proportion of air. During this operation the fuel drawn upwardly through the primary conduit 12 is equally distributed circumferentially about the plate 19 due to the even suction created by the arrangement of the secondary conduit. The fuel upon thus leaving the conduit 12 literally hugs the top wall of the diffusing plate 19 by reason of the fact that the valve 21 is drawn down so as to somewhat restrict the passage and also cause-the channel of the suction to turn sharply about the peripheral edge of the plate 19, making a substantially complete turn, in the reverse direction. The influence of the incoming secondary air also tends to hold the fuel toward the plate 19 so that in being drawn over and around this plate it is diffused and finely separated and atomized. Thus, when the fuel leaves the peripheral edge of the plate 19 and is drawn at a high velocity into the restricted peripheral channel of the mixing chamber and enveloped in the secondary air, the fuel will be further and more fully volatized and carried in this condition to the engine. It will be noted that stratification of the fuel and secondary air is practically impossible, since the fuel which has been considerably vaporized in its passage through the relatively long narrow primary conduit and is further divided and diffused by its distribution and passage over the plate 19 enters a circumferential body of secondary air at a high velocity and in a manner very favorable to producing a fully volatized fuel. During this operation the valve may be said to have an automatic balancing effect, since when the speed is increased by operation of the valve 17 to increase the suction the valve will be opened to a greater extent. The increased suction will draw the fuel from th primary conduit at a greater velocity, so that the tendency of the fuel will be to pass upwardly and over and out of contact with the diffusing plate. However, the valve in being drawn down to a greater extent proportionately restricts the outlet passage from the conduit 12 thereby causing the fuel to be diffused and expanded by the influence most favorable for proper admixture therewith. hen the speed is further increased, the spring pressure on the valve may be increased by adjustment of the lever 31, it being evident that as the spring pressure is increased the supply of secondary airwill be decreased in proportion to the gasolene or kerosene drawn from the nozzle. 'WVhen starting an engine, especially in cold Weather, the lever 31 would be adjusted so as to serve as a choker to practically prevent the admission of secondary air and thus allow a full rich mixture to be drawn to the engine.

While I have shown and described one practical embodiment of my improvements, it should be understood that various changes in the construction and modifications in the design may be made without departing from the spirit and scope of the invention as expressed in the appended claims.

I claim:

1. In a carbureter, the combination of a primary mixture tube, a secondary mixing chamber having an air inlet port and a mixture outlet, an inwardly opening disk valve for said port, said tube extending into said mixing chamber through the mixture outlet end. thereof, a fuel nozzle in said tube, and a distributing disk within the mixing chamber at the discharge end of the primary mixture tube, co-axial with the disk valve and positioned between the valve and mixture outlet, whereby the primary mixture will be. radially distributed by said plate and will be drawn into a peripheral body of secondary air in the mixing chamher and thence through the mixture outlet in the opposite direction from that in the primary mixture tube.

2. In a carbureter, the combination of a vertical primary mixture tube, a fuel nozzle at the lower portion of said tube, a distributing disk at the upper or discharge end of the tube, a mixing chamber surrounding the distributing disk and having an air inlet port above the disk and a mixture outlet below and co-axial with the disk, whereby to cause the primary mixture drawn upwardly through the primary tube to pass outwardly over the distributing disk into the mixing chamber and around the peripheral edge of said disk and thence downwardly through the mixture outlet, and an inwardly opening valve for said air inlet port for admitting secondary air to the mixing chamber.

3. In a carbureter, the combination of a primary mixture tube terminating at its discharge end in an annular distributing disk, the face of which is dished toward the mouth of the primary tube, a mixing chamber surrounding the distributing disk and drawn around the peripheral edge thereand having an air inlet opening at the face of into the mixing chamber and into a peside of said disk and a mixture outlet at ripheralbody'ofsecondary air, and thence 10 the opposite side thereof, and an inwardly in a reverse direction through the mixture 5 opening valve for said air inlet opening, outlet. whereby the primary mixture Will be distributed radially over the face of said disk WILL E. DEWEY.

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