US1657361A - Carburetor - Google Patents

Description

Jan, 24, 1928., 1,657,361

' A. M. ALEXANDRESCU CARBURETOR Filed July 1925 3 Sheets-Sheet 1 IN VEN TOR fllexandrewzz,

' ATTORNEKYI A. M. ALEXANDRESCU CARBURETOR Filed July 2 1925 3 s t -s t 2 iii gunman" INVENZ'OR mndrarcu 3 Sheets-Sheet 5 A. M. ALEXANDRESCU GARBURETOR Filed July 23. 1925 Jan. 24, 1928.

TTORNYS.

Patented Jan. 24, 1928. 7

UNITED STATES PATENT OFFICE.

ALEXANDER m. ALEXANDRESGU, 0E oLEvELAND, OHIO, ASSIGNOR TO THE ALEx CORPORATION, or CLEVELAND, OHIO, A conro m'rron OF OHIO.

CARIBURETOR.

The present invention relates to improvements 1n carburetors, and has for an obect to provide an improved carburetor 1n which a more thorough and intimate mix-' ture of the fuel and air will be promoted, and wherein the vapor in the gasoline tank is utilized for forming the combustible charge instead of being wasted as. under the present practice.

A further object of the invention resides in a greater economy in the use oflthe gasoline, because of this very thorough mixture including the utilization of the gasoline tank vapor.

One of the greatest advantages of the improved carburetor is the great economy effected by passing the air above the float in the float chamber through a small opening, thereby driving the vapor out from the gasoline float chamber. This vapor is drawn into'the carburetor by the suction of the motor. 4

The air that drives the vapor from above the float yields approximately fifteen miles more per gallon of gasoline. The great amount of vapor (atmospheric gas) that every carburetor at the present time is wasting from above its float chambenthrough the breathing hole is thus saved.

A great advantage secured by the 1mproved atomizing or pulverizing system. is the preventing of scoring; in other words, no raw gasoline is permitted .to enter the cylinders of the motor to cut off the lubrication to the pistons, rings and walls of the cylinders. V c

A further objeotof the invention is to provide an improved carburetorwhich will secure quick starting of the motor and-at the same time preventing flooding of the carburetor.

" Further objects of the invention are to avoid smoky exhausts, the reduction and elimination of carbon deposits in the motor,

' greater power from the ignition of the mixture in the motor, and generally to secure,

more responsive action in the motor and the prevention of the burning of the valves.

With the foregoing and other objects in view, the invention will be more fully de scribed hereinafter, and will be more particularly pointedout in the claims appended hereto.

In the drawings, wherein like symbols refer to like or corresponding parts throughout the several'views,

Figure 1 is atop plan view, with parts shown in section, of an improved carburetor constructed according to my present invenion.

Figure 2 is a vertical section taken longitudinally on the line 2-2 in Figure 1.

Figure 3 is a cross section taken on the line 33 also in Figure 1.

Figure 4 is a horizontal section taken on the line 4-4 in Figlire 2.

Figure 5 is a similar section taken on the hue 5-5 in Figure 2.

Figure 6 is a longitudinal vertical Section taken on the line 66 in Figure 1.

Figure 7 is a vertical section taken on the line 7-7 in Figure 1, and additionally showing the gasoline tank in vertical section.

Figure 8 is a side view of the needle valve on an enlarged scale.

Figure 9 is a vertical section showing the atomizing tube taken on an enlarged scale. Figure 10 is an'enlarged elevation of the atomizing sleeve.

Figure 11 is a section taken on the line 1 111 in Figure 10, and

Figure 12 is a perspective view of a valve employed.

Referring to Figure 7, 14 designates the gasoline tank usually at the rear of the automobile, or other vehicle upon which the improved carburetor is installed. This asoline tank is provided with the usual fil ing neck 15 closed 10 the screw cap 16 having the usual vent 1 Usually the gasoline is taken from the bottom of the tank to a vacuum- .tank and the connection for this purpose is indicated at 18. The-liquid gasoline v is pulled from the tank 14 by the vacuum in the vacuum tank and is then circulated to the carburetor. the vacuum tank has been left out, and in Figure 3 the pipe 18 is-shown as connected through the side wall of the shell 19 of the carburetor. Many automobiles do not use the vacuum tank and. in this case the pipe 18 will extend directly to the carburetor. A passage 20 in the shell places the gasoline in communication with the float chamber 21.

The float valve 22 controls the entrance of the gasoline to the float chamber and this valve is under the control of the float 23 hinged as indicated at 24 to a bracket or For purposes of clearness other support. The float rises with the liquid gasohne in the float chamber and "closes the valve 22, thereby avoiding flooding of the carburetor in accordance with a well known practice. Again adverting to Figure 7 a dome is made above the gasoline tank at a convenient point, and is in communication by means of the perforations 26 in the top of the tank with the vapor space above the gasoline body, whereby this vapor may be collected in the dome and circulated through the pipe 27 to the carburetor. As shown in Figures 1 and 7 this pipe 27 introduces the gasoline vapor to the space directly in advance of the throttle valve 28.

As shown in Figures 3 and 6 the gasoline from' the float chamber 21 passes through the screen 29 and into the hollow column 30 through the perforations 31. From this point the liquid gasoline ascends into the nozzle 32, which is provided at the base with the threaded enlargement 33 for screwing into the column 30. There is a slot 34 in the base of the nozzle for the urpose of screwing the nozzle in and out o the column. The nozzle is provided at its upper end with a conical or flared seat 35 for the point of the needle valve 36. The needle valve may be operated by the hand piece 37 shown in Figure 8 directly above the carburetor or by the connection indicated at 38, in Figure 6, which extends to the instrument board of the vehicle.

The needle valve 36 is provided with the screw threads 39 in the body thereof, which take into similar threads 40 in the passage down through the top of the carburetor shell provided to receive this needle valve. By the turning of the valvein either direction the point 41 of the valve is moved toward or from the seat 35 in the nozzle 32 and the flow of gasoline is regulated in the usual less numbers. The shoulders are shown as pinges to there being annular and as interposing progressivel wider abutments for the ascending aso 'e to strike against. The shoulders ormtargets against which the gasoline imy break up the gasoline and atomize the same.

The gasoline is formed into a spray or mist by this practice'and these shoulders or abutments are arranged directly in the path of the air, and the shouldered portion of the needle is housed within a sleeve 43,shown particularly in Figures 10 and 11. This sleeve is open at its bottom and surrounds the nozzle. It is also open at its top portion to slip about the needle valve and to permit the needle valve to turn therein. The sleeve may be fitted frictionally in the needle opening of the carburetor and in the hollow post 30, or it maybe held therein in any appropriate manner. At the air side of the carburetor the wall of the sleeve is provided with a number of perforations 44. all exposed to the in rushing air. These perforations are arranged opposite the steps of the needle, so as to direct the air in minute I streams to the gasoline at the point of impact with the shoulders. The side of the sleeve next the throttle valve is slotted vertically and provided with teeth or serrations 45 at both vertical side edges of the slot. The points of these teeth extend around and the converging side edges of the teeth all form sharp points and edges against which the commingled air and gasoline is made to pass, thus further assisting to break up,

atomize and commingle the air and gasoline. The shoulders 42 of the needle valve will direct the gasoline laterally and horizontally represents a plug having a socket 91 to receive a coil spring 92 and a friction shoe 93 which conforms at its outer edge to the bearing portion of the choke valve and is urged against this choke valve by the coil spring. Plug 90 is held by the rivets 94, shown in Figures 1 and 6, to the cover plate '95. In turn this cover plate 95 is removably secured to the carburetor shell by the screws or other fastenings 96. This friction shoe, under tension of the spring, will preventthe choke valve from vibratin and chattering, compelling the choke va ve to undergo -a comparatively slow movement in opening and closing. The choke valve 47 is operated by thesuction of the motor. according to the opening and closing of the throttle valve 28. The weight or gravity of the chokevalve controls the suction of more or less fuel and the vapor from the gasoline tank and float chamber. Observe in Figure 6 the two lines indicating the tilted position of the carburetor in going up and down grade. In going up grade, weight of the choke valve will act more effectively against the suction of the motor, thus making it more diflicult to open the choke valve and requirin a greater amount of suction to do this wor k. Consefluently, a richer mixture will be drawn from sition illustrated. As shown in Figure 6,

the carburetor nozzle and from the two vapor sources. In going downhill, when the motor is under less load and strain, the carburetor is so tilted that the choke valve 47 will open upon a comparatively light suction and the mixture will thus be diluted and considerable gasoline saved by this automatic performance of the choke valve. When the choke control lever 51, which is normally held by the spring 52, against the stop 53, is pulled in the direction of the arrow, shown in Figure 2, the screw 50 is moved down against the shoulder 54 (Figure 6) of the choke valve. In this case the valve 47 cannot be lifted, because the head of the screw 50 acts as a stop. The screw head is moved-to the position just referred to when starting the cold motor in order to draw a rich mixture to the engine. An air by-pass 55 is made in the shell of the carburetor paralleling the carburetting chamber. Air is supplied to this passage through the opening 56 which is outwardly of the choke valve (see Figure 6). The by-pass 55 is adapted to convey air through the passage 57 to the vapor space in the float chamber 21. The gaseous vapor picked up by the air circulating over the body of fluid in the float chamber is conveyed off from the float chamber by the passages 58 and 59 to thev carburetting chamber adjacent the throttle valve 28. These passages are shown in Figures 4, 5, 6 and 7 The mixture of air and fuel vapor gives a quick start to the engine in the coldest weather and prevents raw gasoline from entering the cylinders thatfloods the motor, destroying it, causing scoring of the cylinders, etc.

The by-pass' 55, as shown in Figure 3, connects by the downwardly extending'passage 60, with the space about the nozzle 32. The nozzle is smaller than the sleeve 43 and forms an annular air passage w ere the nozzle extends up into the lower. pq' tion of the sleeve. The sleeve is frusto-conical thus increasing the velocity of the air which ascends from the base of the nozzle, and causes the air to pick up the "gasoline from the top of the nozzle as governed by the position of the needle valve. p I

The by-pass 55 further communicates by a passage 61 of small cross sectional area with a larger passage 62 connecting with the duct 63 which carries the air about the throttle valve 28. The by-pass will thus furnish air directly to the engine whenever pumping action takes place therein, through the small cross sectional area passage 61. The passage 61' is, however, by-passed by the passage 64 controlled by the valve 65 which valve is shown in Figure 12. The valve is carried be lifted to the combustion chambers,

down upon the wall of the passage-64 and act as guides for the valve, while the upper wider portion of the tip seats against the bottom of the passage 64. The stem 66 slides in the hollow cap 68, shown in Figure '2, and a coil spring 69 wound about the valve stem urges the valve to a closed position.

The air will enter through the passage 56, without regard to the closed position of the choke valve 47 and entering the by-pass 55 will be distributed to the three places above mentioned. That air which goes to the float chamber will result in the formation of a mixture of air and fuel vapor which is circulated to the motor through the openings 58 and 59. That air which descends through the passage will be lifted about the noz-.

zle drawing the gasoline upwardly therewith through the nozzle. This gasoline and air will impinge a ainst the shoulders of the needle valve within the circumscribed space of the sleeve 43. This mixture of gasoline and air will be broken up and atomized as hereinbefore explained, and will bedrawn into the motor, mixing with the vaporized fuel ascending throu h the perforators 58 and 59 and also with the vapor. from the gasoline tank. This forms a very rich mixture, which is, very effective in starting the motor in the coldest weather,

Ordinarily the spring 69 will be of a strength to keep the valve closed, so that no air will pass throu h the relatively large passage 64 which para lels the restricted passage 61. However, if the operator inadvertently omits to turn on the switch and keeps the starter in operation for some time, the tendency will be to create a degree of vacuum which is undesirable as drawing up oil from the crank case past the pistons to relieve this vacuum.

It is the purpose of the valve 65 to provide an easier andquicker relief for any abnormally strong vacuum produced in the motor at this time. The spring "69 will be selected as of a strength to meet these conditions and to permit opening of the valve and the supply of the vacuum-breaking'air invalve 65 maybe described as followsz'forfl operating thecar at high speed and necessity demands a quick stop, the o erator will close the throttle valve 28 first y removing the brake operating foot from the throttle control and afterwards releasing the clutch the oilfrom the crank ease up about t e pistons and into the combustion chambers. This is, of course, disadvantageous. In accordance with the present invention, under the conditions just noted, the valve 65 will open in obeyance to this great suction and will relieve it with atmospheric air before 'also tends to rotate the she the oil can be drawn up about the piston rings. The valve does not yield readily and consequently opens only when the suc-- tion increases to a high degree, such as is sufficient to draw the oil in the crank case past the pistons. The braking eflect ofthe engine, turned over by the momentum of the vehicle, is not lessened up to this high suction.

Most drivers at the present time will leave the clutch in when running down grade, although the throttle valve is closed. The compression of the engine is used to brake the car. This is another situation in which the unrelieved suction in the motor tends to draw up oil from the'crank case above the pistons. To remedy this situation, the valve 65 in the improved carburetor will open to relieve this vacuum.

At 99 is shown a cotter pin for holding the shaft 48 permanently in place. spring 52 urges the shaft long'tudinally and The cotter pin 99 prevents the spring 52 from ejecting the shaft from the carburetor.

Air is constantly entering the-gasoline tank 14 through. the vent l7 and through the filling neck 15. This air absorbs the vapor in the upper part of the tank and the vapor is drawn to the carburetor under the operation of the throttle valve.

In addition the "vapor from the gasoline tank at the rear of the automobile is furnished through the pi the throttle valve, so t at I provide a three fold source of mixture, one from the gasoline tank at the rear of the automobile, secondly from the float chamber of the carburetor, and thirdly from the nozzle of the carburetor. These combustible vapors, ordinarily wasted are thus utilized to the economy of the mixture requiredto be furnished at the nozzle of the carburetor.

It is obvious that various 'changes and modifications may be made in the details of construction and design of the above specifi The 27 at a point near cally described embodiment of this invention without departing from the spirit thereof, such chan s and modifications being restricted only y the scope of the following claims What is claimed is 1. A carburetor comprising a shell having a carburetting chamber, a fuel supply nozzle opening into said carburetting chamber, a plurality of consecutively step ed bafiie means for interrupting and de ecting the flow of fuel from the nozzle, and a separate air supply means for and disposed opposite to each of said bafile means for admixing air separately and intimately with the fuel at each point of interruption and deflection of the latter.

2. A carburetor comprising a shell having a carburetting chamber therein, a fuel nozzle opening into the carburetting chamber, a valve for controlling said nozzle and having a plurality of stepped shoulders for interrupting and deflecting the fuel enters ing the carburetting chamber, and means for supplying separate iets of air independently to the stepped shoulders for intimately admixing the air with the fuel at the points of interruption and deflection thereof as the fuel enters the carburetting chamber.

3. In a carburetor having a fuel nozzle and a needle valve controlling the fuel nozzle and provided with stepped shoulders out wardly thereof to receive and deflect fuel issuing from the nozzle, an air distributing tube surrounding the needle valve and having air admission openings arranged in alinement with said stepped shoulders and provided at one side with a longitudinal slot exposing the needle valve, the marginal edge portions of the tube at said, slot being serrated to break u and commingle the separate streams of air from the openings in the tube and the separate streams of fuel deflected from said stepped shoulders.

4. A carburetor comprising a casing having a mixing chamber therein, throttle and choke valves means for supplying a mixture of air. and fuel to said mixing chamber, a byass extendin about said throttle and cho e valves an said mixture supplying means, saidby-pass having a portion of restricted cross sectional area, a secondary b pass of larger cross sectional area within the first by-pass, and a valve operated only by a high suction for said secondary by- P ALEXANDER M. ALEXANDRESCU.

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