US3875266A

US3875266A - Carburetor for an internal combustion engine

Info

Publication number: US3875266A
Application number: US370416A
Authority: US
Inventors: Dezso Fonagy
Original assignee: Individual
Current assignee: Individual
Priority date: 1973-01-26
Filing date: 1973-06-15
Publication date: 1975-04-01
Anticipated expiration: 1992-04-01
Also published as: BE810161A; CH574568A5

Abstract

An improved carburetor for an internal combustion engine is disclosed. A mixing chamber with means for creating air turbulence and improved homogenization of the air-fuel mixture is provided. The disclosed carburetor comprises a lower portion having an opening adapted to be connected to the suction side or inlet of the engine, a partially closed compartment provided with a cover, a valve regulating the air passage through this opening and thus transmission into the compartment of the reduced pressure produced by the suction effect of the engine, and a set of pipings forming an arrangement of fuel lines adapted to be connected to a fuel supply and having fuel distribution means arranged for adding, in an appropriate manner, the homogeneous air-fuel mixture necessary for each running speed of the engine. Improved combustion and lower level of noxious emission gases are effected.

Description

United States Patent 11 1 1111 3,875,266 Fonagy 1 1 Apr. 1, 1975 [54] CARBURETOR FOR AN INTERNAL 3,273,869 9/1966 Morton 261/50 A COMBUSTION ENGINE 3,298,677 1/1967 Anderson... 261/65 3,701,513 10/1972 Carter 261/50 A Inventor: Egg p gcy i s. gtidd la 3.720.403 3 1973 Winquist et a1 261/50 A t 1 2 2;; emev'ces me FOREIGN PATENTS R APPLICATIONS 7 1.043129 11/1953 France 261/50 A [-2] FIled: June 15, 1973 207,926 12/1923 United Kingdom 261/65 [21] Appl. No.: 370,416

Primary ExaminerT|m R. M11es F A r r P t D Attorney, Agent, or FI'rmWerner W. Kleeman oreIgn pp ma non non y a a Jan. 26. 1973 Switzerland 1143/73 [57] ABSTRACT [521 [LS CL 261/50 A 261/65 261/79 R An improved carburetor for an internal combustion 1] CL h 9/12 engine is disclosed. A mixing chamber with means for 1581 6,6 ,15111a;11111111111111? al/56A, 79 R, 65 creutiflsair turbvlenceimd improved hor'iogeflizmion of the aIr-fueI mIxture 1s prov1ded. The dIsclosed car- [56] References and bgreto:i corgprises a lows/er pgrtion having1 an opening a apte to e connecte tot e suctlon 51 e or In et 0 UNITED STATES PATENTS the engine, a partially closed compartment provided 7.31.292 3/1904 Johunson 261/50 A i h a Cover a valve regulating the air passage *i- T 361/79 R through this opening and thus transmission into the E compartment of the reduced pressure produced by the {h4g 1mg 0mm 561/50 A suction effect of the engine, and a set of pipings form- 111711220 /1025 Tungve: .11: 261/79 R mg an arrangement of fuel lines adapted be 1547323 7/1025 Hcnn cquin 261/5 A nected to a fuel su l and having fuel distribution 1.606.491 1 1/1926 Aherncth ct a1 261/50 A m an rrang f r ing. in an ppropri te manner. 1.620.925 3/1927 Tungye 261/79 R the homogeneous air-fuel mixture necessary for each 1.927.090 9/1933 Hess 261/7 R running speed of the engine. Improved combustion 3 2 1 3: 2 1 3" a v a and lower level of noxious emission gases are effected.

.1. .3 a1 crt. r. 3.265.374 8/1966 Morton 261/ A 9 Claims, 16 Drawing Figures FUEL "RBYPRZESC PATENTEUAPR 11975 M m F FIGJS PIATENTEUAFR H975 3.87Eh266 SIHT 5 UP FUEL FIG. I6

CARBURETOR FOR AN INTERNAL COMBUSTION ENGINE It is known that air carburization devices from liquid fuel such as gasoline for feeding the internal combustion engines, devices commonly called carburetors, condition to a very important measure the proper func tioning of these engines and consequently their efficiency just as they do the amount of pollution caused by the exhaust gases.

Thus. applied to engines of motor vehicles just as to stationary engines. these carburetor devices can have a great influence on the operational efficiency and long life of these engines and functioning defects can be a cause of atmospheric pollution.

Thus. these carburetors are provided with complex air-fuel regulating systems to he able to meet the different functioning loads which the problematic operation conditions of these motor vehicles impose on their engines. These adjustments are delicate and as a result difficult and they should be frequently effected.

in addition. known carburetors are each adapted to a predetermined type of engine which involves a rather large number of carburetor types and particular adjustements for each one of these types.

Up to now attempts or proposals made in view of ob taining carburetors suitably arranged in a way as to improve the fuel dosage and to thus avoid the waste constituted by incompletely burned fuel surpluses, a source of bad efficiency and of pollution, have not led to really satisfactory results. in any case, not for all possible running speeds of a gasoline engine. It is known, on the other hand, that the fuel used for motor vehicles more often contains additives. notably lead. and that the presence of these additives in the exhaust gases of these devices. not or too little neutralized by oxidation at the time of the burnings of the combustion engine, has even become a pollution problem of an importance comparable to that of the presence of carbon monoxide.

It is. therefore. a primary object of this invention to furnish a carburetor with which an advantageous solution is found from the technical and cost point of view for the above-mentioned problems and particularly for the pollution problem and with it that of efficiency.

More particularly. it is an object of this invention to provide a carburetor for a gasoline engine or internal combustion engine of a type employing fuel injection with conventional fuel pumps and the like. A system of outlets is provided for introducing the fuel to means for conditioning the fuel flow. Fuel atomizing means are provided for and according to one of the aspects of the invention. means for the homogenization of the atomized air-fuel mixture and for the refinement of the components and additives of this mixture are also foreseen in order to cause. in the said mixture, a homogeneous distribution of the said components and/or additives in a finely divided form.

Another object of the present invention is to provide a carburetor as above-described wherein the outlets are arranged above the butterfly-valve without the intermediary presence of a float chamber being necessary and are subject to the difference in pressure between the fuel feed and the compartment formed in the tubu lar body above the butterfly-valve just as to the action of said means conditioning the flow.

An important object of the presence invention is to provide a carburetor for use with a fuel injection system where means for inducing turbulence in the incoming air is provided to attain a more homogeneous airfuel mixture.

in a particularly advantageous and effective embodiment corresponding to one of the aspects of the invention. the said means for the homogenization of the mixture comprise grooves formed in the inner surface of the said compartment which channel the mixture in the direction of the butterfly-valve. However. it is to be understood that other techniques for inducing turbulence are contemplated. Thus. for example. baffle-like structures may be employed. These homogenization means can also advantageously include means for forcing a whirling movement of the air passing through said compartment. According to the invention, the said homogenization comprises, in a particularly advantageous way, both the said roughness obtained by the grooves and the said means for forcing a whirling movement, the latter being arranged to cause whirling movement in a determined direction, and the said roughness con sists of helocoidal grooves downwardly shaped in the inverse sense to that of the said whirl movement.

Advantageously, the said means for forcing a whirling comprises holes made in the cover at the top of the said compartment. these holes being closed by means of elastically backdrawn flap-valves connected under the cover in a way as to open for enabling the passage of air in a deflected way, these flap-valves being mounted head to tail on both sides of the cover center so as to allow for a whirling of the entering air in the desired given direction. As a variation, these means can comprise oblique borings which are made in the side wall of the said compartment, in the upper part of the latter, according to a line non-converging with the axis of the volume forming the compartment.

It seems that the hammering of the mixture which whirls against a rough surface plays an important role in the functioning of the engine and causes a notable reduction of pollution which can be mainly attributed to the refinement of the main components which enables a complete combustion as long as it is combined with the proper amount of fuel. Working tests of a motor vehicle provided with a carburetor according to the embodiments of the present invention have revealed a reduction of the fuel consumption and of the pollution by exhaust gases. Tests have also shown that a single carburetor model of the type according to the invention may be suitable for engines of different strength equipping motor cars.

According to another advantageous aspect of the in vention promoting a good efficiency of the engine and a good combustion at different running speeds of the engine. the said fuel flow conditioning means comprises a device sensitive to at least one of the two joint parameters which are the pressure differential and the kinetic energy of the air flow, this sensitive device having adjusting means connected to at least one said outlets in order to control the distribution of a fuel flow adapted to each of the running speeds ofthe engine and having an equipment able to vary the passage which it opens to the fuel flow according to a predetermined function, susceptible of being non-linear, of the air flow or of the pressure in the said compartment.

Advantageously, the sensitive device comprises a shutter element susceptible of being moved against retraction means and connected to means for regulating the fuel flow. said equipment being at least partially constituted by said means for the retraction of the shutter element, which perferably comprises two springs which establish the said equipment by being successively applied to the shutter element as fast as a displacement of the latter takes place under the action of the air flow or of the pressure differential, one of these springs only entering into action, to notably increase the coefficient of the elastic retraction, after a part of the course of the shutter element on which only the other spring acts.

According to still another aspect of the invention, the said compartment is formed in a tubular body which presents itself in the general form of a funnel, the butterfly-valve being mounted in the tubular part having the smallest transverse dimensions of this body and the said compartment being formed in the truncated-cone shaped part of the funnel form. The main fuel outlet for regulating the jet and susceptible of being completely closed, is advantageously positioned at the center of the top of the funnel form, a device sensitive to the pressure differential and/or to the kinetic energy of the air flow in this compartment being adapted to more or less seal off or free the said main fuel outlet and comprising, for reacting to the action of the pressure differential and/or the kinetic energy of the air flow, a shutter element mounted coaxially to the funnel form around a tube comprising the said main fuel outlet in order to be arranged in a circular opening equally coaxial to the funnel form of the said compartment and made in the cover of the latter.

These different aspects as well as other features of the invention will now be explained, by way of nonlimiting example, in connection with the attached drawings in which:

FIG. 1 represents a perspective view of a first em bodiment of a carburetor of the type in question;

FIGS. 2 and 3 represent an axial sectional view and a cross-sectional view, respectively, of the carburetor of FIG. I;

FIG. 4 represents a plan view of an element of the carburetor of FIG. 1',

FIG. 5 represents a perspective view on a relatively small scale of an improved second embodiment of a carburetor of the type in question;

FIG. 6 represents an axial sectional view of two sets of elements intended to be assembled with each other to form the carturetor of FIG. 5;

FIGS. 7 and 8 are vertical and plan sectional views, respectively, of the main arrangement of FIG. 6;

FIG. 9 is a cross-section view of the other arrangement of FIG. 6;

FIGS. 10 and 11 represent axial sectional and crosssectional views, respectively, on a large scale, of the elements of the arrangement of FIGS. 7 and 8;

FIG. 12 represents a relatively small-scaled axial sectional view of an advantageous variation of the embodiment of FIGS. 1 to 4;

FIGS. 13 to 15 represent plan and sectional views, respectively, of an element fitted with the main means of the variation of FIG. 12', and

FIG. 16 illustrates in partial section another embodiment of the fuel injection system according to the present invention with the lower portion showing the piston feature thereof.

In FIG. 1, an element la is illustrated having the shape of a truncated cone the smaller base of which is fixed to one of the ends of a cylindrical casing or socket 1b; this latter being arranged coaxially to the truncated cone.

A plate 2, having holes 20, is transversely arranged with respect to the common geometric axis of the elements la, lb, and is fixed to the other end of the cylindrical casing lb to constitute a collar arrangement of this assembly la, 1b with the aid of screws or of bolts.

Moreover, an element 3 shown in the form of a spherical cap having holes 30, the edge diameter of which is equal to that of the large base of the element In and is assembled to the latter, as will be explained hereinafter.

Furthermore, an arm 4a is perpendicularly fixed on to a bolt 4b which is engaged in a hole radially made in the cylindrical casing lb, as will be explained below.

In addition, a screw 5 having a milled head and equipped with a counter-nut is screwed into a threaded hole in this casing lb at a level slightly above the bolt 4b with respect to the collar 2', the angular distance allowed between the bolt 4b and this screw 5 being almost equal to 90".

Finally, a tube element 6, the diameter of which is relatively small, is fixed onto the element 1 above the screw 5.

In FIGS. 2 and 3, the elements la to 6, described above, are again illustrated. The element la is tubular and constitutes, with the element lb, a body 1 in the form of a funnel.

The edge of the cap 3 is made in the form of an annular rib, the inner lateral surface of which comprises a thread adapted to that which is made on the inner lateral surface of a step lr, this step being made on the edge of the wall of the element In and which permits assembling the cap 3 to the body 1.

A plate 7 in the form of a disk, the diameter of which is adapted to a free engaging of this disk in the threading, is pressed into this step by the edge of the cap 3. This disk 7 comprises a rectangular opening 7a the median axis of which, relative to the longer sides, almost corresponds to a diameter of this disk. The latter also has two holes 71 respectively situated on both sides of the opening a plaquette 7p is connected to each of these holes by a screw and a threaded hole in the disk 7 to allow a regulating of the passage of fluid into or through this hole.

Two idntical brackets 7b are welded to the under surface of the disk 7 arranged parallel to each other and on each side of the extension of the longer sides of the opening 7a; each of these two brackets has a hole for a connecting pin which is transversely arranged with respect to the direction of the longer sides of this opening 7a.

A small rectangular plate 8, the width of which is a little smaller than that of the opening 7a, is appropriately mounted on the connecting pin 80 to constitute a shutter element. A relatively short bolt 8b is perpendicularly fixed to the upper surface of this shutter element 8 and extends through opening 7a above the disk 7', the free end of this bolt 8b comprises a hooking ring for one of the ends of a draw-spring 9, the other end of which is appropriately hooked to a support 7c which is fixed to the upper part of the surface of the disk 7 a good bit behind the small side corresponding to the opening 711.

A small round member 10 of a relatively flexible plastic material which does not react to mineral fuel is fixed by a force fit into an adequate recess on a bracket 8p mounted under the plate 8 (or shutter element) at a certain distance from the under surface of the latter.

Moreover, a small tube element 11 is arranged almost perpendicular to the direction of the plane defined by the disk 7 and above the small round member 10; one of the ends of this tube 11 being fixed to one of the ends of a tubular arm lla, the other end part of which is bent into an elbow then counter-bent at right angles to be fitted into a notch or hole made on the edge of the disk 7. This arm thus constitutes a piping system arranged in the form of an angle bracket above the disk 7.

The step lr also has a radial notch constituting an airtight recess for the counter-bent end of the arm 110 which is made to be gripped in this notch by the edge of the cap 3.

It will be noted that the tube ll includes an outlet H situated at a lower level than that of the inner surface of the plate 8 which the tube ll passes through. In the closed position of plate 8, the small round member 10 bears against the outlet 110 forming a closure stopper whereas the end of the tube constitutes a stop abutment of the plate 8; the tension of the spring 9 and the dimensions relative to the elements connected to the disk 7 being appropriately determined to yield their desired effects. In addition, the boring or internal diameter of the tube 11 ranges from 0.6 0.9 mm.

Furthermore. the wall of the body 1 has a conduit 12 opening into the fitting hole or notch of the counterbent end of the bracket like member 11a corresponding to the hole of this latter.

This conduit extends approximately lengthwise to the hole forming a housing for the screw and the tube 6 is forcedly mounted in a hole opening into this conduit 12 to constitute a piping system or canalization system which allows the distribution of a liquid to the outlet I of the tube ll and to the housing of the screw 5; the latter opening onto the inner surface of the casing lb in the form of an outlet in which the passage section can be regulated in atypical manner by a needle-valve positioned on the end of this screw 5. It should be mentioned that the opening into the casing 11; occurs above the butterfly-valve 4, to permit contact of the inlet fuel with the turbulent air.

The bolt 4b diametrically extends into the boring of the casing lb and a butterfly-valve 4 is fixed to this bolt 4b to allow a regulating of the passage section for a flow of fluid into the channel formed by this cylindrical casing. Furthermore (FIGS. 2 and 4) the edge of the butterfly-valve 4 has indentations or notches 42 of small dimensions which permit a small passage section to a fluid in the closed position of the butterfly-valve 4.

lmportantly. the inner surface of the body 1, situated below the disk 7, is roughened to provide means for creating air turbulence and good air-fuel mixing. Preferably. the inner surface of the body 1 is formed with tiny transversal grooves 13 the dimensions of which can be varied greatly. The grooves may be spiral-shaped or any other configuration which will impart the requisite roughness.

Furthermore. it will be noted that the color 2 is adapted to be mounted on the suction or induction pipe of an internal combustion engine fitting, for example. a motor car.

the tube 6 can be coupled by a flexible pipe or piping to the delivery tube of the fuel pump of an engine. and that the lever 40 of the butterfly-valve 4 can be coupled, in a conventional manner, to the accelerator pedal" of the car so that this device assures the carburation necessary for the functioning of the engine of this car.

From the foregoing, it should be understood that the suction of the engine produces, from holes 30 of the cap, an air current which successively passes through the opening 7a and the holes 7r to the tubular body 1; the flow of this current being regulated at will by ope ration of the butterfly-valve 4. According to the flow of this current of air, that is to say according to the position of the butterfly-valve 4, the pressure in the truncated compartment formed between the butterfly-valve 4 and the plate or shutter element 8 varies slightly from the intake pressure of the engine and the atmospheric pressure. The current of air resulting from the difference of pressure, or the pressure differential coupled with the force of the current of air, tends to push the shutter element 8 (arrowf,) to unblock the opening 7a and free the outlet of the tube 11 through which a fuel jet can escape under the pressure p" of the fuel pump (not shown).

The stopper l0 constitutes, therefore. a deflector assuring a radial dispersion of this jet which crosses or intersects the air current before reaching the rough wall of the body 1. Of course, the action of the current of air or of the pressure on the shutter element 8 is a function of the position of the butterfly-valve 4 and is counter balanced by the action of the spring 9 (arrow f the weight of the shutter element 8 being negligible with respect to this action. In a way, each position of the stopper 10 corresponds to a position of the butterfly-valve 4 taking into conderation the suction of the engine and determines the value of the fuel jet flow; the course of this stopper 10 with respect to the outlet 1 10 being relatively small.

The intersecting of the current of air and of the dispersion level of this jet produces eddies in the compartment situated below the disk 7', these eddies being fa vorable to an homogenous carburation of this air by the fuel. Moreover, the roughness of the surface due to the grooves 13 has an unexpected influence on this carburation, as is confirmed by a comparison with utilization of bodies 1 with smooth walls (the smooth wall produces less favorable results).

Of course, this carburation in the compartment cov ered by the disk 7 is produced for the different running speeds determined by the positions of the butterflyvalve 4 from a threshhold value of the action of the air current on the shutter element 8; this threshhold value corresponding to the limiting value of the tension arrow f which the spring Q should assure to close the opening 110.

This threshhold value is adapted to the closure position of the butterfly-valve 4 in the conduit and to which the idling of the engine corresponds.

The flow of air necessary for this load is, therefore. limited by the indentations or notches 42 of the butterfly-valve 4 and the corresponding quantity of fuel is distributed under the pressure of the pump through the outlet of the housing of the screw 5.

This outlet of the housing of the screw 5, whose diameter is almost equal to 1 mm, is made in the wall of the casing lb, without particular regard as to its position, above the butterfly-valve 4 as well as the grooves 13 which arre made down to the base of the conduit.

have an astonishing influence on the efficiency of the carburation for this idling speed. This influence ap pears as compared with different test results with elements or bodies that have more or less smooth walls.

Finally, a single device conformable to that described above is suitable for a very wide range of engine capabilities. Such a model has indeed been successively mounted on cars of very different capacities such as a ZCV CITROEN (435 cm), a GS CITROEN (lOl cm), a R l6 RENAULT (I565 cm), a 504 PEUGEOT (I971 cm), a PLYMOUTH 8 cylinders (4773 cm).

For operational performances similar to the usual performances of these cars, this model has assured an exellcnt carburation in every case; these working tests corresponding to a global run of more than 20,000 km.

Each transposition of this device from one engine to the other only required an adaptation of the position of the plaquettes 7p of the cover 7 and of the screw 5 to produce, respectively, an excess of air and a fuel flow for the idling speed suitable for the different engines; these adaptations being experimentally effected but being simple and rapid.

In all cases, this device, which avoids among others the use of an air filter, obtained excellent functioning conditions with the engine used resulting in a fuel economy which could be evaluated at 6 to 8 percent of the usual consumption of this engine. The different engines thus tested remained relatively cold and analyses of their exhaust gases revealed a rate or proportion of carbon monoxide equal to 0.02 percent.

Finally, it is understood that such a device can be manufactured from a small number of elements; these elements being simple and practically need no particular regulating after their assembly in the body 1. Thus, it is not necessary to gauge the distribution outlets of the tube 11 or the housing of the screw 5.

In this regard. the shutter element 8draw-spring 9 apparatus seems to be the most delicate part of the system, even though the spring 9 needs no particularly careful fabrication except for regulating its tension. Thus. the results indicated above were obtained with a spring comprising 24 turns made of steel wire with a diameter of 0.7 mm; the outer diameter of the coil" being 5.5 mm and its length in the resting position being 16 mm.

In the same way, the rectangular shape of the shutter element 8, the length of which is slightly more than twice its width, is very suitable to this simple manufacturing. Nevertheless, other shapes, preferably having two symmetry axes or more (ellipse, ovum, trapezium, cross-shaped could produce good results.

Moreover, the functioning of the carburetor, even in the idling speed, is not disturbed by ts position with respect to the horizontal plane as opposed to classical carburetors; it can be used in practically any position which can simplify the relative arrangements of the other parts of the engine. This possibility is also favorable for the equipment of vehicles (boats, planes, motorcycles l which may have variable operational seats or saddles.

FIGS. 5 to represent another embodiment of a carburetor of this invention.

In the FIGS. 5 to 10, a tubular element 21 is provided in the form of a funnel fixed to a mounting collar 22 on the suction side or inlet of an internal combustion engine (not shown) and equipped with a cap" 23 by means of a threading at the edge of this cap 23 and to a threading at the edge of the element 21 as is described in detail for the above-mentioned embodiment of FIGS. 1-4.

A butterfly-valve 24 (FIGS. 6, 9), the edge of which having notches 24e, is mounted in a convenient way on an axis 24a in a cylindrical part of the conduit formed by this element 21 and is controlled by an arm 24b fixed at the outer side of the element 21 onto the end of this axis 240 in order to regulate a current of air in this conduit.

It will be noted that a bolt element, forming a finger 21g arranged at the interior of the conduit of the ele ment 21, is forcedly mounted in a hole radially made in the wall of the element 21 slightly lower than the level of the axis 240 of the butterfly-valve 24, to constitute an abutment assuring a transversal state of this butterfly-valve in the cylindrical part of the conduit practically perpendicular to the geometric axis XX of the element 21.

The cap 23 (FIGS. 6, 7, 8) is shown in the form of a ring 230 provided with a handle like member 23b diametrically arranged and provided with two openings 23:) symetrically situated on both sides of the handle like member 23b.

This annular part or ring 23a comprises holes 23: which obliquely extend with respect to the axis XX of the element 21 and with respect to a transversal plane of this axis XX; it will be noted that the inner surface of this ring 230 is truncated and coaxial to this axis XX.

A tube element 31 is coaxially mounted to the cap 23 on the axial part of the handle like member 2311 by means of a threaded part ofthis tube 31 and a threaded hole in the axial portion ofthe handle like member 2311; this screw mounting being assured in a conventional manner by a counter-nut 31 A tube element 31!, bent at right angles, is conveniently fixed to the upper end of the tube 31 to form a mouth-piece to be connected to a flexible tubing, not shown.

Furthermore, a relatively thick disk 28, shown in the form ofa truncated cone, includes an axial hole permitting a free sliding motion of this disk 28 on the tube 31 and is engaged on the latter.

The end part of the tube 31 which is opposite the handle like member 23b is equipped, as will be explained further on, with a small round member 315 thick enough to form a seating for one of the ends of a spiral spring 29 adapted to the diameter of the tube 31 and destined to operate by compression; the other end of this spring 29 is guided, in a conventional manner, in an annular lodging or recess coaxial to the sliding hole on the tube 31 (FIG. 10).

It will be indicated that the slant of the lateral surface of the disk 28 is identical to that of the ring 23a and that the diameters of the truncated surfaces of this ring 23a and of this disk 28, respectively, and the thickness e of the latter permit a closure of the openings 230 of the cap 23 by this disk 28 whch thus forms a shutter element."

The wall of the end part of the tube 31 includes three small radial holes 31! of a diameter in the order of l mm; these holes being made in a same transversal plane situated slightly below the plane of the lower edge of the ring 230 and forming, between each other, an angular distance of about (FIGS. 10, ll).

Finally. the free end of the tube 31 comprises a threading permitting the mounting of a tubular element 25 suitably threaded. having an end engaged in the tube 31 made in the form of a needle-valve 25b which extends above the level of the holes 31: in order to modify. notably by throttling. the flowing conditions of a liquid in these holes 3h. This needle-valve 25b constitutes. therefore. a means for regulating the flow similar to the conventional needle-valve screws for regulating fluid flows; it permits. if desired. greatly reducing the effective passing section of the holes 31!.

In addition. the small round member 31s forming a seating for the spring 29 includes a threading adapted to the threading of the needle-valve screw" 25 in order to constitute a counter-nut assuring the rigidness of this arrangement.

Furthermore, the other end ofthe needlevalve screw 25 is made in the form of a small tube 31a. and a disk 30. of a flexible material resistant to the action of the fuel. is positioned adjacent the free outlet of this tube 3 la.

This disk 30. forming a closure stopper. is. as a matter of fact. forcedly engaged in a circular recessing which is made in the central part ofa disk 30d, the edge 30b of which extends outwardly and upwardly from the edge of the stopper 30 forming a bowl-like member.

This bowl disk 32d is welded to the median part of a metal strip 28 suitably bent in the form of a suspension stirrup and fixed by its ends to the under surface of the shutter element 28 by screws.

It has been already explained in detail. in connection with the embodiment of FIGS. I to 4. how this device can equip an internal combustion engine or gas engine in view of supplying it with carburated air and it will be noted that the holes 3lr and the outlet of the tube 31a constitute a system which is well adapted to the distribution of fuel quantities necessary for the different running speeds of the engine; the holes 311 assuring the air carburation admitted by the holes I3! for the idling.

In addition. it will be noted that the inner surface of the ring 23a constitutes a jet deflector for the holes 3]! and that this system of distribution is as far away as possible from the butterfly-valve 24. Moreover. the trans versal position of the butterfly-valve 24, due to the abutment 21g. assures a uniform distribution of the flow of gases necessary for this idling of the engine.

Finally. for the other running speeds. the stopper 30 constitutes. for the jet of the tube outlet 310. a deflector producing a radial dispersion of this jet. as described in detail above (arrowfZ). But, in the embodiment of FIG. 10. the edge 30b of the bowl forms another deflector for the fuel level which results. which produces an atomizing of at least a part ofthis fuel level or nappe (arrow f6).

In this regard. it will be noted that there would be no particular difficulty in arranging. for example on the tube 3!. a blade device of the screw or spiral type adapted to be rotated under the effect of the air current notably that from the jets of the slanting" holes 231 and adapted to a mechanical action of the atomizing of the jets of the holes 31! and of the level or nappe of the tube 31a.

A bladed wheel. or even an arrangement of counter rotating wheels could. as a matter of fact. be mounted on a small "thrust ball bearing" fixed to the nut-seating 31s; the suspension stirrup 28p having. therefore, a form adapted to the dimensions of this arrangement.

This thrust ball bearing could also be mounted on the median part of the tube 31, the spring 29 being replaced by a spiral tension spring mounted at the exterior" between the handle like member 23b and the shutter member 28.

It will be noted that the speed of the engine of a 504 Peugeot car fed by a dvice such as that of FIG. 10 can be maintained in the idling position at 500 rpm whereas a conventional carburetor applied to this engine can only provide, theoretically. a minimal speed of 740 rpm. but in practice a good stability of the idling can only be obtained at a speed of from 800 to 900 rpm.

Tests of the exhaust gases have revealed that for all running speeds, including the ilding, the burning of the exhaust gases could be complete; apparatuses used for these tests were not sensitive enough to reveal traces of carbon monoxide.

Furthermore. the temperature of this engine remains at a value much lower than that which is observed of similar running speeds when the engine is fed by its conventional carburetor. This results in less wear and consequently a saving on lubrication oil.

Referring now to FIGS. 12 to 15, these are illustrated improvements to the fuel distribution means associated with the carburetor of this invention.

In FIG. 12, a tubular element 41 is found fixed to a collar 42 equipped with a cap 43, a disk 47 and a butterfly-valve 44 with notches 44c, as in the embodiment according to the FIGS. 1 to 4.

This disk 47 comprises a rectangular opening 47a fitted with a shutter element 48 (owing to connection brackets 47b) and two holes 472 respectively situated at one side and the other of this opening 47a (FIGS. l3, 14. 15).

This disk forming partition 47 has a radial hole 47r defined and extended inwardly by a tubular element 51 and equipped with a small tube 46 permitting a connection to fuel supply pump owing to a notch at the edge of the element 41 (FIG. 12).

In addition. (FIG. 14). a needle-valve screw 45 is suitably mounted in a hole 45f intersection the hole 47r to regulate a fuel flow in a small tube 450. and a narrow plaquette 52 is fixed at an angle to the partition 47 under the opening of the tube 45a.

Furthermore. another small tube 51a directed downwardly having a small diameter in the order of millimeters opens into the tube 51 and is arranged almost axially passing through the hole of the shutter element 48 in a way that its free outlet is situated below this shutter element approximately a centimeter from the under surface of the partition 47. The shutter element 48 is. moreover. equipped with a stopper 50 by means of a bracket 48p.

In addition. two draw-springs 49a. 49b. hooked to supports 54a. 54b, respectively. assure a drawback of the shutter element 48 towards the opening 47a; these supports being fixed on the upper surface of the partition 47 on both sides of the needle valve screw 45.

These springs 49a. 4% are made of relatively fine wire of a diameter of three-tenths to five-tenths mm and are in the form of a spiral" of a diameter of approximately 4.5 mm and a length of 20 mm. Furthermore. the spring 49a is slightly stretched to assure a small butting effect of the stopper 50 on the free outlet of the tube 510 whereas for this position the hooking of the other spring onto its support 54a and onto the shutter element 48 is assured, conventionally, by rings having a play of 1 mm.

Finally. a plaquette 47p is arranged under the lower surface of the partition 47 beneath each of the holes 47r to close the latter. Each of these plaquettes 47p is, as a matter of fact, joined in a conventional way onto a small support permitting a fixation of the partition 47 and a small draw-back spring (not numbered) is mounted between this support and its plaquette to form, in a usual way, a small closure or flap valve.

It is observed that these two closure valves 47p are directed in the inverse sense (one is connected at the right and other at the left)v The pressure differential (or the air current) never opens these closure valves to the point where they are perpendicular to the partition 47, thus the air entering by the holes 47! is obliquely directed and its movement takes a tangential component. As the air is directed towards the left by one closure valve and towards the right by the other, a whirling results which causes the further pressing of air against the interior lateral wall of the element 41. An identical whirling effect is produced by the oblique holes 23! in the embodiments according to FIGS. 1 to 7.

The grooves of the interior wall of the funnel (represented in FIG. 6), grooves which are also present in the embodiment according to FIGS. 12 to 15, are not circular but helicoidal with a relatively pronounced in cline (one or two turns or rounds to traverse the whole height). the pitch of these grooves being of the opposite sense to that of the descending air whirl. The effect ofthese grooves, which the whirl crosses, is, thus, nota bly reinforced. This effect, already mentioned, can be explained by a hammering of the air-fuel mixture against the walls of the funnel. This hammering, or eddy, causes the mixture to be more homogeneous and in particular the lead particles (heavier and thus more sensitive to the centrifugal force) are more finely separated and better distributed in the mixture. When the combustion takes place they can burn better as they are finer and better distributed with respect to the oxygen. The hammering by the grooves, increased by the whirling and the inverse inclination of the grooves, per mits, therefore, a notable decrease or even an elimination of additive residues in the exhaust gases.

In view ofthe foregoing, the means, adapted to cause (or reinforce) the descending whirl of air and adapted to make this whirling move in a determined sense, are particularly important. These means consist of head to tail closure valves 47p in the embodiment according to FIGS. 12 to 15 and of oblique holes 231 in the embodiment according to FIGS. 5 to 11.

It should be understood that the displacement of the stopper 50 by the action of the air current on the shutter element 48 for regulating the fuel flow is effected in opposition to resisting strain successively applied to this shutter element 48 by the spring 49a then by the two

springs

49a and 49b. One can imagine that it is pos sible to use elastic systems obtaining, as a function of the position of the shutter element, a resistance well adapted to the variation of the fuel flow which is necessary for a good continuity of successive running speeds of a motor vehicle engine.

This device has assured, also in the idling speed, the normal running speed of 500 rpm of a "504 Peugeot" car engine.

Furthermore, a running limit ranging between 500 and approximately 2,000 rpm corresponds to the initial extension of about 1 mm of the spring 49a and it is only for running speeds greater than this latter value that the action of the second spring 49b is added to that of the first spring 49a.

For these running speeds, the combustion of the exhaust gases can be complete and the engine temperature is also reduced.

In addition, it will be specified that holes 47! of a diameter of about 12 mm, equipped with closure valves nneding a load in the order of one gram to be removed from their seating (arrow f5), permit compliance to the needs of engines of present cars" in which the capacities are within the range of 450 to more than 4,000 cm.

Finally, a device conforming to that of FIGS. 12 to 15 has been constructed by using plastic material of the polyamide type commonly called nylon (heraclon); the walls of the truncated part of the body I having, with respect to the axis of the body, a slant or incline corresponding to an angle of almost 16.

This model produced the results indicated above.

Moreover, it will be noted that an elastic system such as that mentioned above regarding the elastic shutter 48, could be applied to the embodiment of FIGS. 5 to I0 and that closure valve devices, causing similar effects as those of the closure valves 47p, could be connected to holes of the ring 23 similar to the holes 23! of this embodiment.

Finally, the inconveniences of conventional carburetors are sufficiently known to the public so that the advantages of a device according to the invention is clearly understandable from the preceding description; these advantages, therefore, are simply enumerated as follows:

This device is simple: the embodiment of FIG. 5 comprises only two main parts; a body 21 fitted with a butterfly-valve and a cap 23 equipped with a fuel circuit, means for regulating the flow and for the fuel atomizing.

The embodiment of FIG. [2 comprises only three main parts; a body 4], a partition 47 and a cap 43.

The device results in a saving of material and oflabor due to this simplicity.

The weight of this device of FIG. 5 is, indeed, of the order of 0.500 kg whereas a conventional carburetor and its parts uded for a 504 Peugeot car, for example, weights more than 6 kg.

In addition, it spares the labor for the assembling and for the regulating of the starter, the manifold jets. the acceleration pump and of the warming up circuits needed for a conventional carburetor.

It also produces a fuel saving of 6 to 8 percent due to a good combustion which results in a lower functioning temperature for the engine,

a saving of oil due to this reduction of temperature as well as a risk reduction of valve carbonizing, of leakage" of connecting rod and of deterioration of the cylinder head joint.

It facilitates the starting up ofa cold engine, also, due to the fact of the reduction of functioning temperature of the engine.

It avoids atmospheric pollution.

It can be applied to an extended range of engine capacities of from 200 cm to more than 4,000 cm".

It can equip engines of vehicles with variable operational seatings (motorcycle, boat, plane It avoids fuel reserves, a cause of burning in the case where a car accidentally overturns.

Generally, the particular phenomena which occur, often in an unfavorable way, in a conventional jet do not occur with a carburetor of the type described here because it is not, as in a conventional carburetor. a pressure differential of the venturi type which acts to draw off the fuel but it is directly the suction (or the current of air) coming from the suction inlet conduit of the engine. There results from the stopper-valve construction in the carburetor described here that there is no necessity to have a float chamber which maintains the fuel at an approximately constant level, the fuel inflow of the carburetor can be directly connected on a fuel pump or directly to a fuel reservoir placed higher than the carburetor.

In a conventional carburetor, a doubling of the flow of air-fuel mixture involves an approximate fourfold of the pressure differential which establishes this flow. In the carburetor of this invention, owing to the fact that the fuel and air inlet sections enlarge as a consequence of the movement towards the interior of the shutter element fixed to the stopper, an increase of flow does not involve a pressure differential increase as great as in the case of a conventional carburetor. In point of fact, with the carburetor described here, a doubling of the air and fuel inflow only involves less than twice the pressure differential. This is extremely important for the functioning of an engine at higher running speeds.

It is to be noted that whereas with a conventional carburetor the main jet continues to furnish fuel, irregularly, in idling position which means that the idling jet proper has only a complementary supply role, better regulated and more regular, with the carburetor described here there is no fuel coming from the fuel injection outlet in idling position. Consequently, the idling jet can be regulated to furnish itself. in a regular manner, all of the fuel necessary for the idling speed. There results from this advantageous feature that an engine equipped with a carburetor described here can start up in diverse conditions without necessitating a supplenientar starter jet as exists with conventional carburetors. As a matter of fact. as during idling absolutely no fuel comes from the element which delivers this fuel at normal running. the idling nozzle can be regulated to furnish more fuel than an idling jet (of auxiliary role) of a conventional carburetor. There is therefore suffi cient fuel arriving in a regular enough manner so that the starting up of the engine can be made even when cold.

Furthermore. it is noted that by an abrupt opening of the butterfly-valve (an action which in a conventional carburetor makes the acceleration pump function) the shutter element effects an abrupt movement suited to furnish. with the required suddenness. the exact amount of atomized air-fuel mixture necessary for the acceleration of the engine.

Referring now to FIG. 16 which illustrates in section another preferred embodiment of the present invention and represents a variation of that shown in FIGS. -11. In this embodiment the needle-valve assembly 25 is replaced with a piston assembly 90. The piston assembly 90 comprises a fuel inlet conduit 92 secured to the carburetor upper portion 94 with a locking nut 96 and passing through an opening 98 of a movable choke plate 102. Near the lower portion of conduit 92 is formed an enlarged portion 104 with a shoulder 105 provided to retain spring 106 thereon. Spring 106 provides upward biasing against an inner shoulder 10621 of the choke plate 102. Piston 107 includes an upper cylindrical portion 108 which slides upwardly or downwardly within conduit 92 for reasons to be made more apparent hereinafter. A removable plug 109 with a predrilled hole 111 is threadably secured to portion 108 and is secured by the lower portion of the cradle 113, the cradle being secured by bolts 114 or the like. to lower portion of the choke plate 102. The cradle 113 is of open construction to permit gas to pass therethrough. Also the portion 104 has openings 112 which are upwardly directed to permit the fuel to be injected into the chamber via conduit 92 as shown by the arrow F. In normal operation the incoming fuel would be ejected through the openings 112 with a certain quantity of fuel passing through opening 111 which is provided in the plug 109. The fuel which leaves through opening 111 is normally used for idling purposes as well as in normal operation. The purpose of the piston 107 is to control the quantity of fuel which is ejected through openings 112. The position of piston 107 is dependent on the operating conditions of the vehicle or engine rpm. The pressure conditions in the chamber are such that the choke plate 102 moves up and down, in turn moving the piston within the conduit 92, contacting the openings 112 to either partially close or par tially open the holes 112. In this way the amount of fuel entering the chamber is regulated along with the air.

Means are provided internally of piston 107 for regulating the degree of idle. Thus, the lower portion of piston 107, namely, the plug 109, is detachable from the upper portion so that the opening or nozzle 111 can be changed. In this way different idling characteristics can be provided for different vehicles. Plug 109 is detachable from the upper portion 108 of the piston 107 by use of an internal thread, with the lower portion 109 being provided with a mating external thread 120. Thus, various nozzle sizes can be provided in plug 109, for example, for a larger vehicle. a larger opening is provided so that the idling characteristics conform with the requirements of the larger vehicle. Similarly, a smaller vehicle would require a nozzle of smaller size such that the requirements of the smaller vehicle are also provided.

Another feature of the present invention is that there is an absence of mechanical or electrical linkages between the upper choke plate and the lower butterflyvalve. However, in some cases mechanical or electrical linkage can be provided.

Although the invention has been specifically illustrated and described with reference to particular embodiments thereof, it is contemplated that minor modifications could be made therein without departing from the spirit of the invention.

It is claimed:

1. A carburetor for an internal combustion engine comprising a lower portion having an opening adapted to be connected to a suction inlet of the engine, a partially closed compartment defining an air passage therethrough extending upwardly from said opening and being provided with a cover, valve means for regulating the air passage through said opening thereby controlling the transmission into said compartment of the reduced pressure produced by the suction effect of the engine, piping means including an arrangement of fuel lines adapted to be connected to a fuel supply and provided with fuel distribution means for providing an air-fuel mixture necessary for each running speed of the engine, said fuel distribution means comprising a system of outlets connected to means for conditioning the fuel flow, said conditioning means including a device sensitive to at least one of the two joint parameters which are the reduced pressure and the kinetic energy of the air current, said sensitive device comprises fuel outflow regulating means which cooperates with an outlet to control the distribution of a fuel flow adapted to each of the running speeds of the engine, said compartment being formed in a tubular body which has the general form of a funnel, said valve means comprising a butterfly valve being mounted in the tubular part hav ing the smallest transversal dimension of this body and the said compartment being formed in the truncated part of the funnel form, the main jet fuel outlet, regulatable and susceptible of being completely closed, comprising calibrated openings provided in the lower part of the wall of a conduit having the form of a tube element secured to said cover at the center of the height of the funnel form, directed towards the bottom coaxially to this form, whereby said tube element forms at least a part of said arrangement of fuel lines and said sensitive device comprising a movable choke plate crossed through at its center by said tube element and displacing itself coaxially to said tube element and to the funnel form to control an air inflow through an opening made in the cover of said compartment. the movement of said choke plate being controlled against the action of elastic retraction means by the suction in the said compartment, said main fuel outlets being controllably opened or closed relative to the amount of said air inflow, said fuel outflow regulating means of said sensitive device being fixedly connected to said movable choke plate by an open cradle means under said choke plate and includes a piston slidingly positioned at the lower end of the fuel outlet conduit for controlling the fuel discharged through said calibrated openings in said fuel conduit, said choke plate being constructed and positioned relative to said main outlets and said fuel outflow regulating means for causing fuel to be ejected directly below said choke plate in the part of said compartment where reduced pressure from the engine is primarily introduced, whereby the fuel impacts the incoming air under optimum conditions for intimate mixing with each other.

2. A carburetor according to claim 1, wherein said calibrated openings in the wall of said conduit are obliquely directed in such a manner that fuel ejection occurs upwardly, toward the marginal portion of the under surface of said choke plate to contact and admix with the entering air which passes around the periph' eral edge of said choke plate into the mixing chamber under said choke plate.

3. A carburetor according to claim 1 comprising atomizing and homogenizing means for providing a homogeneous distribution of the fuel-air components in finely divided form, said atomizing and homogenizing means comprising a helicoidal ribbing of the lateral surface of said compartment and means for forcing the air entering and passing through said compartment to effect a descending whirling movement as it traverses said helicoidal ribbing.

4. A carburetor as defined in claim 1 including a mixing chamber below said choke plate wherein predetermined quantities of fuel and air are brought together for intimate mixing, means for creating air turbulence within said mixing chamber whereby a homogeneous air-fuel mixture is effected.

5. A carburetor as defined in claim 4 wherein said means for creating air turbulence comprise groove means formed on the inner surface of said mixing chamber.

6. A carburetor as defined in claim 4 wherein said fuel inlet conduit communicates with fuel injection means, said movable choke plate in operable association with said fuel inlet conduit, said calibrated openings located intermediate the upper and lower ends of said fuel conduit in communication with said chamber means for regulating the amount of fuel passing through said calibrated openings.

7. A carburetor as defined in claim 6 wherein said piston-like member has an upper portion slidably positioned in the lower portion of said fuel conduit adjacent said calibrated openings and an enlarged lower portion with means for permitting idling fuel to pass therethrough.

8. A carburetor according to claim 1 wherein said piston includes removable plug means having aperture means for passing predetermined quantities of fuel into said mixing chamber for idling purposes.

9. A carburetor according to claim 8 wherein said piston is fixedly secured to said choke plate cradle and comprises a hollow conduit having an exterior surface slidingly conforming to the inner surface of said fuel conduit and an interior surface having thread means for engaging corresponding thread means provided in said plug means.

Claims

1. A carburetor for an internal combustion engine comprising a lower portion having an opening adapted to be connected to a suction inlet of the engine, a partially closed compartment defining an air passage therethrough extending upwardly from said opening and being provided with a cover, valve means for regulating the air passage through said opening thereby controlling the transmission into said compartment of the reduced pressure produced by the suction effect of the engine, piping means including an arrangement of fuel lines adapted to be connected to a fuel supply and provided with fuel distribution means for providing an air-fuel mixture necessary for each running speed of the engine, said fuel distribution means comprising a system of outlets connected to means for conditioning the fuel flow, said conditioning means including a device sensitive to at least one of the two joint parameters which are the reduced pressure and the kinetic energy of the air current, said sensitive device comprises fuel outflow regulating means which cooperates with an outlet to control the distribution of a fuel flow adapted to each of the running speeds of the engine, said compartment being formed in a tubular body which has the general form of a funnel, said valve means comprising a butterfly-valve being mounted in the tubular part having the smallest transversal dimension of this body and the said compartment being formed in the truncatEd part of the funnel form, the main jet fuel outlet, regulatable and susceptible of being completely closed, comprising calibrated openings provided in the lower part of the wall of a conduit having the form of a tube element secured to said cover at the center of the height of the funnel form, directed towards the bottom coaxially to this form, whereby said tube element forms at least a part of said arrangement of fuel lines and said sensitive device comprising a movable choke plate crossed through at its center by said tube element and displacing itself coaxially to said tube element and to the funnel form to control an air inflow through an opening made in the cover of said compartment, the movement of said choke plate being controlled against the action of elastic retraction means by the suction in the said compartment, said main fuel outlets being controllably opened or closed relative to the amount of said air inflow, said fuel outflow regulating means of said sensitive device being fixedly connected to said movable choke plate by an open cradle means under said choke plate and includes a piston slidingly positioned at the lower end of the fuel outlet conduit for controlling the fuel discharged through said calibrated openings in said fuel conduit, said choke plate being constructed and positioned relative to said main outlets and said fuel outflow regulating means for causing fuel to be ejected directly below said choke plate in the part of said compartment where reduced pressure from the engine is primarily introduced, whereby the fuel impacts the incoming air under optimum conditions for intimate mixing with each other.

2. A carburetor according to claim 1, wherein said calibrated openings in the wall of said conduit are obliquely directed in such a manner that fuel ejection occurs upwardly, toward the marginal portion of the under surface of said choke plate to contact and admix with the entering air which passes around the peripheral edge of said choke plate into the mixing chamber under said choke plate.