US1893896A

US1893896A - Carburetor

Info

Publication number: US1893896A
Application number: US138365A
Authority: US
Inventors: Victor R Heftler
Original assignee: Societe du Carburateur Zenith SA
Current assignee: Societe du Carburateur Zenith SA
Priority date: 1926-09-03
Filing date: 1926-09-03
Publication date: 1933-01-10
Anticipated expiration: 1950-01-10

Description

V. R. HEFTLER Jan. 10,11933.

CABBURETOR 4 ,Sheets-Sheet l Filed Sept. 3, 1926 INVENTOR n QQN N Q1 um@ Hmm Jan. 10, 1933. v. R. HEFTLER GARBURETR Y Filed sept. 5. 192e C (lf-Sigh.

4sneets-sn'eet s d j@ 5.a P-39.69 NOA/mmm fig. 0. E596 AIR T0 NEEDLE /lJoZQ/R To NozzLE l 49 45 l f l l i d IE@ 7 AIR ro WELL NO AIR T0 NEEDLE I a (Eg 7 NO AIR TO WELL o loo/AIR 'ra WELL AIRl T0 WELL.

AIR To wel.; 100% AIR To WELL. 'AIR To wsu.

N AIR Toweu.. L/rrLE Amro WELL N0 AIR T0 NEEDLE N0 AIR T0 NOZZLE N0 AIR T0 NOZZLE AIR T0 NOZZLE /007a/AIR 7'0 NOZZLE AIR To FL oA'r CHR. AIR ro FLOAT CHR. AIR ToFLoA-r CHR. V AIR To FzoA-r ffl/R. [00% AIR T0 FLOATCHR.

INVENTOR *(MAMJLL Jan. 10, L1933. v. R. HEFTLER GARBURETOR Filed Sept. 3, 1926 4 Sheets-Sheet 4 INVENTOR @nl/ /IWv III! @NRM

Patented Jan. 10, 1933 UNITEDl STATES Paesane PATENT Frlca VICTOR R. HEFTLER, OF DETROIT, MICHIGAN, ASSIGNOR T SOCIETE DU CAVBBTEUE ZENITH, OF LYON, FRANCE, A GGEPORATION 0F FMNCE CARB'UEEEE Application led September S, H536. Serial No. 135,365.

rlhev present invention relates broadly to the art of Carburation, and more particularly to improvements in carburetor structures of the character adapted for use with internal combustion engines.

At the present time it is recognized theart to which the present invention relates that with ordinary carburetor constructions desirable mixtures are not produced at all speeds or under all conditions of operation. lWith at least most of the commercial carburetors there is a so-called flat spot at some one speed in the carburetor operation, this llat spot preventing that uniformity ot motor operation or acceleration which is desired.

liany diderent attempts have been made to correct defects of the character referred to Mock, No. 1,395,233 of October 25, 1921.

Corrective measures as applied to the air system at the present time have usually been predicated upon increased eiiiciency in the suction producing means. Not infrequently recourse has been had todouble venturis for this purpose. Experience has demonstratedhowever, that while double venturis do give an increased suction and thereby elect a fuel l'low at a correspondingly less air flow, and necessarily overcome the initial handicap sooner, they have a very decidedly objectionable operation throughout aportion of their range, which is usually at a speed of substantially fteen miles an hour.

In most carburetors there is' some ditliculty involved the change from operation withlow throttle opening to operation withlarger throttle opening, due tothe fact that, in the first position, most of the fuel comes from idling kholes positioned near the lower edge of the throttle, lwhile at'higher speeds it -53 comes from nozzles located in the venturi.

This 'transfer of operations is not infrequently accompanied with irregularities in the mixture, whether the transfer be slow and gradual or sudden.` ln the construction of many present day carburetors the fuel supply for idling purposes is taken from an open well, ied through a restricted opening from the doet chamber, and in which the level neoessarily drops while the carburetor is in operation, so that the reserve of fuel which is depended upon for sudden acceleration is de-1 pleted by the idling jet. The present invention contemplates improved means forV maintaining, during very low idling, a reserve I of fuel at the normal level. 'lhis can be drawn upon in case of sudden acceleration, and by reason of its high level will be more easily drawn into the mixing chamber, while providing fuel for very low idling and without increasing the fuel delivery necessitated for compensation.

rl`he present invention contemplates improved means Vfor etlecting the elimination of the so-called dat spots by improving 'the fuel supply and therebv obviating the necessity of utilizing double venturis or similar means with their attendant irregular suction multiplication factor at dill'erent speeds.

ln the accompanying drawings there is illustrated a. preferred embodiment of the present invention, it being understood that the drawings do not define the limits of my invention, as changes in the construction and operation disclosed therein may be made without departing either from the spirit of the invention or the scope of my broader claims. Y

In the drawings:

Figure 1 is a vertical sectional viewA through one form of carburetor constructed in accordance with the present invention;

Figure 2 is a vertical sectional view on the line II-II of Figure 1 looking in the direc tion of the arrows;

Figure 3 is a transverse sectional view on the line III- III of Figure 1 lookingin the direction of the arrows; Figure 2 and Figure 3 being ona slightly enlarged scale;

I Figure 4 is a detailse'ctional view on an `10 Figures enlarged scale on the line IV-LIV of Figure 1 Fi e 5 is a transverse sectional view on the line V-V of Figure l through the ven- 5 turi and illustrating the arrangement of fuel nozzles;

Figures 6, 6b, 6, 6d and 6e are detail sectional' views, artly diagrammatic, on. the

line VI-VI o Figure 2;

7*, 7b, 7, 7d and 7e are views similar to those just referred to on either of the lines VII-VII of Figure 2;

Figures 8*, 8", 8c, 8d and 8 are similar views on the line VIII-VIII of Figure 2; and

Figures 9*, 9", 9, 9d and 9e are similar views on the line IX--IX of Figure 2, it being' apb parent that successive views in each group of gures illustrate the parts in different operative position. Figure 10 is a dia ammatic view showing the Huid passages rom their source to the point where they enter the mixing chamber.

y The present invention is illustrated inconnection with a carburetor of the Zenith 'type in which there is a suction nozzle responsive to the depression existing within the venturi and Vone or more supplemental nozzles: designed to feed a substantially constant amount of fuel irrespective of suction. to v thereby compensate for the low speed leanness of the suction nozzle. In carburetors of this type it has been customary to feed fuel to the low speed device from the atmospheric well. In operation the slow speed device lowers the fuel level' in the atmospheric well during the idling of the carburetor so that if the throttle is suddenly opened fuel must be drawn, not from the level represented by the normal level maintained in the float ,40 chamber, but from the lower level established by the slow speeddevice in the atmospheric well. This results in a lag between the fuel and the air and the consequent production of a; ilat spot.

I have proposedto correct such an operation by providing a plurality of atmospheric wells each receiving fuel through a calibrated op'ening, and feeding the'slow speed device from Vone of the wells. Experiments have v demonstrated the impracticability of such a construction, however, for the reason that the well serving the slow speed device soonbecomes exhausted. This exhaustion cannot be 'prevented as it is impractical to use a larger calibrated opening leading thereto inasmuch as the sum of the two calibrated openings to the two wells must bear a definite relation to the main nozzle, and as the calibrated opening which serves the well delivering to the 09 slow speed device is made larger the opening to theother atmospheric well must be made correspondingly smaller, and the refilling period for such other well has thereby been:

unduly' increased.

In accordance with the present invention an improved operating structure is provided while retaining all of the adventages of the two types of feed and the atmospheric wells.

Referring more particularly to Figure 10,

the fuel flows from a fuel inlet 18 to a strainer 19 and from the strainer to a float chamber 6. The float chamber is connected by a'conduit 21 to a main nozzle 22 in the mixin Vchamber 2. The mixing chamber is provi ed with a throttle 29 having openings 36 therein. The float chamber 6 is connected by separate conduits 26 to

wells

32 and 27 The well 27 is connected by a conduit 24 to an auxiliary nozzle 37 in the mixing chamber 2 adjacent the main nozzle 22. The well 32 is connected y a conduit 25 to another auxiliary nozzle 38 also adjacent the `main nozzle 22. The well 27 has a quill 28e leading to a chamber 39 which is connected by conduit 30 vto an outlet 30 in the mixing chamber 2. The

outlet 30 is located above the throttle 29. The well 32 is connected by a quill 33a, which is larger than the corresponding quill '280, to a chamber 40 from which the fuel passes through the conduit 34 to an outlet 34 in the mixing chamber below'the throttle 29.

An air valve 45 regulates the air supplied to the float chamber 6, the

wells

27 and 32, and the

chambers

39 and 40 in which the quills 280 and 33a are located. Air issupplied from the air valve 45 to the float chamber 6 through a conduit 58.

Conduits

49 and 59 supply air to the

chambers

40 and 39 respectively. A conduit indicated in Figure 10 as 54 and 51 supplies air from the air valve to the wells 32^and 27.

The air valve 45 is actuated in accordance with the position of the throttle 29 to supply air through the

passages

49, 58,`59 and 54 andy 51 in accordance with whether the motor is idling or is operating at slow speed or at high speed. When the motor is idling fuel issupplied from the well 27 through the quill 280, chamber 39 and conduit 30 to the outlet 30 in the mixing chamber. When the throttle is opened to a slight extent in order to make the motor operate at a slow speed, fuel is supplied from the well 32 through the quill 33a chamber 40 and conduit 34 to the opening 34 in the mixing chamber 2. When the motor is operating at idling speed, no fuel is supplied from the

wells

27 or 32 to the

auxiliary nozzles

37 and 38, and no fuel is fed from the float chamber 6 to the main nozzle 22. The control of the flow of fuel through the

conduits

30', 34', 24 and 25 is determined by the amount of air supplied through

conduits

59 and 49 to the

chambers

39 and 40. If air is supplied through the

conduits

59 and 49 it lowers the suction in the' conduits 30' and 34', and if air is also supplied to the

wells

27 and 32 through the

conduits

54 and 51, the fuel is caused to flow through the

conduits

24 and 2,5 to the

auxiliary nozzles

37 and 38.

i lt-will be seen that each of the

wells

27 and 32 has an outlet leading to an auxiliary nozzle in the mixing chamber. Each of these wells also has a quill which leads uel to the mixing chamber when the motor is either idling or operating at low speeds. 'lhe detailed construction and operation ot the car: buretor will be understood from the following description taken in connection with the other gures of the drawings.

As illustrated in the drawings, a carburetor embodying this invention may comprise body sections A `and B adapted to be secured togather in any desired manner, and composed otd the sanie or diderent materials as may be desired. Eatending through the section B is an opening 2 forming a carbureting chamber and adapted to receive a venturi 3 suitably held in position therein as by a screw l. Air `lor the venturi is supplied through the inlet 5 in the section A.

Formed in the section A is a doet chamber ii adapted to receive a doat 7 having a pivotal mou tingi and eective for maintaining a const nt level in the float chamber by cooperation with a valve stem 3. The valve stem is. conveniently operated by providing an intermediate lever 10 having a suitable pivotal mounting ll and adapted to engage the yalve stem 9 upon upward movement thereof. The valve stem is mounted for movement in arholder l2-threaded upwardly into the laterally projecting shel' on the section At its upper end the valve stem carries a ring i3- within which is located a ball valve 14 adapted to cooperate with the .seat l5 for cutting ed fuel supply to the float chamber. llt is desirable to provide means whereby the inlet valve, its seat and holder can be assembled as a sub-unit, tested as such, andthat the distance l), Figure from the seating tace ot the holder to the tip oi3 the valve stein, when the valve is seated, be. maintained at a standard value. This greatly facilitates the manufacturing and servicing of carburetors in the held. .For this purpose the valve seat l5 is preierably formed on an inner member 16 slidably mounted in the nut l2. llhen the parts havek been properly adjusted, the nut and the inner member i6 may be secured in adjusted position by solder 17 or the like. lt will be noted that the tip oi the inner member 16 extends well up into the hlter chamber so as to receiveviuel from the upper position thereof instead oi the .lower position. 'lliis provides sort oi a sump into which dirt, water and the like may accumulate without possibility of being drawn into the vitals of the carburetor.

'lhe fuel supplied to the carburetor may be obtained through an adjustable connection 18, as well understood in the art, delivering to a lilter 19 located in a` suitable recess 20 in the laterally projecting shelf.

Leading from the lower portion of the iloat chamber is a, passage 21 communicating at its, lower end with a suction nozzle 22 through an opening 23. The outlet of the nozzle 22 may be suitably positioned within the venturi 3, andI preferably at a point slightly beyond the most restricted section of the venturi whereby it is subjected. to the maximum depression obtaining therein.,

Leading from the float chamber on opposite sides ot the opening 2l are passages 2d and 25 respectively, each of these passages having the amount of fuel which passes therethrough controlled by a calibrated plug 23. 'lbe passage 24 leads to a well 27 into which extends a quill assembly 28 adapted to supply fuel to a point above the throttle 29, an

outlet opening 30 into the carbureting chamber being provided for this purpose. lfhis assembly may be oi any desired construction, but preferably comprises a holder 28EL adapted to be threaded upwardly into the section B of the carburetor whereby it may be assembled therein before 'the sections A and B are put together'. 'lhe lower end of the holder 28a is tapped to receive the idling nozzle 28 to which the tubev28", soldered thereto, supplies fuel romthe lower portion of the well 27. The holder may also carry a tubular quill'28c. 'lhe holder 28a is preferably provided with openings 3l` therein for admitting air into the uel stream anterior to the point of discharge thereof whereby an emulsion is formed when the level oi the iuel drops to such a point as to uncover the openings 3l. The upper part of the well, as clearly shown in Figure 3, is quite large and thereby not only insures quite a supply ci fuel for starting, but also delays the time at which the openings 3l are uncovered.

.Y rlhe passage 25 delivers to a second atmospheric well 32 into which extends a quill 33 mounted similarly to the quill 28 and delivering to the carbureting chamber through an outlet opening 34e preferably so located as indicated in lligure l that it is normally-only partially covered when the throttle is in' its closed position. 'lhe quill 33 may be provided with one or more openings 35 by means of which a predetermined amount of air may be continuously passed to the fuel delivered through the opening 34.

lhe throttle is provided with openings 33 extending therethrough to permit the passage of a small amount of air which, however, is not enough for idling; the rest ci the air is suppliedby thevtwo crescent-shaped openings left around the throttle when the latter is slightly opened. l prefer to choose the size of those holes 36 so that the throttle need be opened only a few thousandths of an inch for idling. During this time the depression eXisting at hole 34; isfedective for drawing fuel upwardly in the quill assembly 33 a predetermined distance, this distance preferably being such that there is no discharge of fuel through the outlet 34. As thethrottle is cracked open it will be apparent that the edge of the throttle moves across the outlet 34 and thereby increases the depression to which the assembly 33 is subjected. The condition obtaining at this time is such that fuel will be drawn from the assembly 33 and will discharge into the carburet ing chamber. Ifinstead of gradually continuing the opening movement of the throttle, the throttle is suddenly opened, the absolute pressure to which the assembly 33 is subjected suddenly increases, thus stopping the feed of fuel from the outlet 34 at a time when the fuel level in the assembly 33 is materially above thenormal level in the float chamber.

The well 27 is4 adapted to feed fuel into the venturi through an outlet" nozzle 37, while the well 32 is adapted to deliver fuel into the venturi through a similar nozzle 38. Thus, when the suction at the edge of the throttle is insufficient to draw the fuel through the

ports

30 and 34, fuel is fed to the carbureting chamber through

auxiliary nozzles

37 and 38. When the fuel feed through the port 34 is stopped due to the sudden opening of the throttle, the additional head of fuel will be effective for temporarily increasing the fuel flow through the nozzle 38 and thereby temporarily enriching the mixture to such` an extent that the formation of a flat spot is prevented.

It is obviously desirable to provide means for accurately controlling the characteristics of flow through the

outlet openings

30 and 34. For this purpose there is provided a variable air inlet communicating with the

chambers

39 and 40 surrounding tube 28c and a similar tube inserted in holder 33 respectively. Such a variable control of the air supply may be accomplished by the provision of

needle valves

41 and 42 adapted for the respective control of air delivered through the

openings

43 and 44 leading to the chambers 39 and 40). As moreair is admitted vto either of the chambers, the effect of the suction in the carbureting chamber on the respective quills will be lessened While a restriction in the amount of air will increase the suction effect.

I preferabl provide common valve means whereby the ffbw of air to the respective carburetor parts, including the float chamber, the wells, and the chambers above the quills, may be controlled in `certain predetermined relation. For this purpose I have shown a tubular valve 45 extending transversely through the carburetor body and as formed with open ends closed bv air filtering means 46. The valve 45 may be actuated in any desired manner. as'by a crank arm 47, as well understood in the art. l

The tubular valve 45 is provided with

openings

48 and 55 to control the air to the two low speed quills, with

openings

50, 52 and 53 to control the air to the wells, and with

openings

56 and 57 to control the air to the float chamber. Withthevalve 45 in the closed positions of Figures 6", 7, 8a and 9", the float chamber is open to the admission of air, as in all other positions, but the channels to the wells are closed, as are also the passages to the air adjusting needles. This is the starting position of the parts.

In the next position, shown in Figures 6", 7b, 8b and 9", a little air is allowed into the Wells, but none is allowed to enter the quills.

AThis permits the fuel level to drop in the wells and reduces somewhat the amount of fuel fed to the quills. It is an enriching position from the normal. Air is still freely admitted to the float chamber. v

The next position of the valve, as shown in Figures 6c to 9, inclusive, permits a little greater admission of air to the wells.

Figures 6d to 9d, both inclusive, show a further position in which air is being admitted to the low speed quills and the air to the wells is increased.

In Figures 6 to 9, both inclusive, there isy shown the normal position with maximum air fiow to the various parts controlled by the valve.

The foregoing operations are obtained by the1 connections hereinafter described in detai The opening 48 is adapted to gradually move into registration with a vertically eX- tending passage 49 communicating with the opening 44 under the control of the needle valve 42. With the tubular valve in the posi-A tion of Figure 6IL the opening 48is out of registration with the passage 49. At this time no air will be supplied to the chamber 40 above the quill 3 and the quill will be subjected to the full depression existing below the -throttle. As the valve moves into its next position, the opening 48 approaches but does not come into registry with the passage 49. As the valve 45 is further operated into the position illustrated in Figure 6c, the edge of the opening 48 will be brought into communication with the passage 49. Thereafter vcontinued movement of the valve in the same direction as illustrated in Figures 6l and 6e respectively, will gradually increase the amount of air delivered to the chamber 40 and correspondingly decrease the suction effect on the quill 33. f

1 .The opening or openings 50 are adapted with the parts in the position illustrated in Figure 6 to be out of communication with `an inclined channel 51, indicated in Figure lll the position of Figure 7. As the tubular valve continues to move in the same direction into the position of Figures 7d and 7 e respectively, the amount of air admitted thereby to the wells will'be increased.

'lhe relatively small opening 52 and relatively larger opening 53 are adapted to control the dow ot' airv through an inclined channel 54 similar to the channel 51 and also communicating withthe space above the wells. With the valve in the position of Figure 6a, the interior ot the valve is out of communication with the channel 54, as clearly apparent :trom Figure 8B. Movement ot the valve to the rst position brings the opening 52 into communication with the channel 54, thereby admitting a limited amount of air. lln the position of Figure 8c the opening 52 is in :lull communication with the channel 54, continued movement ot the valve in the same direction moving the opening 52 out ot registration of the channel 54 and gradually bringing the larger opening 53 into registration therewith.

lhe openings

55, 55 and 57 are located in the end of the valve opposite the opening 48 but in the same transverse plane. With the parts in the position illustrated in Figure tia the interior ci the tubular valve will be in communication with the iloat chamber by reason oi the tact that the opening 56 is in registration with the passage 58 leading to the doet chamber. 'lhusatmospheric pressure errists in the doat chamber at this timen As the valve is moved from the position oi Fi ure 9a to Figure 9b the opening 55 gradua ly moves out oi registration with the passage 55, and the opening 57 moves toward a position ot registration with such passage. 'lhe opening 55 likewise moves toward a position ot registration with passage59 communicating with the passage 43 under the control of the needle valve 41. Continued movement ot the valve 45 in the same direction into the position ot Figure .9 brings the yopening only into registration with the passage 59 and leaves the

openings

55 and 57 both in communication with the passage 58. lllontinued movement in the positions oil 55" Figures 9d and 98 respectively, maintains communication with the iloatchamber and estab-y lishes communication with the passage 59V whereby air is admitted to the chamber 39 to counteract the eect ci suction in such chamber. l

Y jectionable 7, 8c and 9c respectively, increases the amount Aoi air to the space above the wells Without adecting the other conditions. Further movement of the valve into the position of Figures 6d, 71,'8d and 9d establishes communication to the chambers 39 and 40v and increases the :dow or' air to the wells Without cutting od the dow to the float chamber. lin its iinal position as represented by the ures of the e group, there is a maximum air a mission to all of the parts. This is desirable as at this time both of the wells are delivering all of their fuel through the

nozzles

37 and 38 respectively and at this time atmospheric pressure should exist in the Wells, or nearly l/Vith a carburetor of the construction herein shown, it will be apparent that there are 'retained all of the advantages of a compound tuel supply system, including a constant'ilow per unit ot time system, and a suction system with the additional advantages of correction of any tendency toward a flat spot. fm accurate control for the supply of air to the various parts of the carburetor is also obtained in denite relation to the opening oil the throttle and in such manner that a rich idling or low speed mixture is iirst supplied through the quill 28, which mixture gradually decreases in richness as the speed of the motor increases and ultimately ceases to function entirely as the feed transfers from the outlet opening 30 to the nozzle 37. As the throttle is gradually opened up to a certain predetermined point, the level of the fuel in the quill 33 gradually rises until at a predetermined throttle position fuel is delivered through the opening 34 to augment the low speed feeding device. As the throttle continues its opening movement the flow ol 'uel through'the opening 34 ceases and the increased head of fuel established by reason of the previously existing suction becomes effective during the period ot transition or suddenv throttle opening for increasing the fuel delivery through the nozzle 38 and thereby facilitating acceleration. During these various operations the supply of air to the wells is accurately controlled, whereby initially pure :fuel issues from the low speed feeding device, this fuel gradually changing to an emulsion, as will be apparent.

vFlith a great number of carburetors as commonly constructed there is a very sob.- action frequently noticeable when, after running for some time on an open throttle, the throttle is suddenly closed. In

some cases the motor supplied by the car-V Ato the normal fuel level. It will be noted that the quill 28" is of comparatively small diameter andlias its gasoline hole 28 located about at theqfuel level, while the quill 33a is of comparatively large diameter and has its gasoline hole 33 located well above the fuel level. By reason of this construction, the quill assembly respondsvery quickly to demands upon it in case of sudden throttle closing, thereby insuring recovery. This is nec essarily true as the fuel does not have to be lifted-any very appreciable amount, so that thereuis no lag in the fuel feeding operation therefrom. With the large quill 33% however, there is a considerable amount of fuel held in thev quill and available for dumping upon sudden throttle opening, to thereby insure smooth change from idling to running.

With the single quill construction heretofore provided these conditions have not been obtainable. In order to insure recovery with such constructions it has been necessary to make the quill ofsmall diameter, and this has in turn materially limited the gasoline available for dumping upon sudden throttle opening. By the present arrangement, these two conditions are effectively reconciled, and this constitutes a highly advantageous feature of the present carburetor.

By reason of the operation set forth, 'an efficient mixture is provided by means of two slow speed feeding devices effective .in certain predetermined relation, each having its own adjusting means, and preferably so arranged that one is operative for slow speed and the other for idling. This insures a desirable quality curve and also a suicient fuel s upply at all times to satisfy the dimensions of the associated motor. The unit valve assembly disclosed herein is ,described and claimed in my co-pending application Serial 1%. 288,670 filed June 27, i928.

Further advantages arise from the provision of a plurality of quills of diiferentcharacteristics, whereby opposed conditions are effectively reconciled.

Still further advantages arise from the unit inlet valve assembly and the ease of standardization thereof, and from the manner of withdrawing fuel from the filter chamber, whereby only clean gasoline passes to the vitals of the carburetor.

1,ses,sae

' I claim:

1. In a carburetor, a carbureting chamber, a main supply of fuel thereto, a plurality of fuel wells, a nozzle delivering fuel from each of said wells to said carbureting chamber, there being supplemental openings from each of said wells for the delivery of fuel to said carbureting chamber above said nozzles, and quill assemblies of different fuel feeding characteristics for transferring fuel from the respective wells to the supplemental opening.

2. In a carburetor, a carbureting chamber, a main supply of fuel thereto a plurality of fuel wells, and a nozzle. delivering fuel from each of said wells to said carbureting chamber, there being supplemental openings from each of said wells for the delivery of fuel to said carbureting chamber above said nozzles, one of the supplemental openings being above and the other being below the throttle in said carburetinr chamber.

3. In a carburetor, a caiiureting chamber, a main supply of fuel thereto, a constant level chamber, a plurality of wells, a fuel feeding quill communicating with each of said wells for delivering fuel to said carbureting chamber independently of said main supply, and valve means for controlling the delivery of air to said float chamber, said wells and said quills.

4. In a carburetor, a carbureting chamber, a plurality of fuel feeding quills of different characteristics relative to fuel dumping leading to said carbureting chamber, and means for feeding fuel to said quills, said means comprisin a Well for each `quill and means for contro ling theair supply to said wells.

5. In a carburetor, a carbureting chamber, a fuel feeding quill of relatively small diameter, a fuel feeding quill of relatively large diameter, both of said quills having a discharge openin adjacent said throttle, and means for feeding fuel to said quills, said means comprising a well for each quill, there being an auxiliary nozzle in the carburetin chamber supplied by each of said wells an adapted to dischar e fuel into said carbureting chamber ya sigbstantial distance below said throttle.

6. In a carburetor, a mixing chamber, a throttle therein, a main nozzle discharging into said chamber, a. 'pluralit of wells, an auxiliary nozzle communicating with each of said wells and effective under predetermined conditions to deliver fuel to said mixing chamber, and quills of different characteristics receiving fuel from said Wells and delivering the same adjacent said throttle.

7. In a carburetor, a mixing chamber, a throttle therein, a main nozzle discharging into said chamber, a pluralit of wells, an auxiliary nozzle communicating with each ing chamber, and uills of different characteristics receiving uel from saidl wells and delivering the same adjacent said throttle, oneof said quills being effective for dumpin a comparatively small quantity of fuel an( the other for dumping a comparatively large quantity of fuel.

8. In a carburetor, a mixing chamber,'a throttle therein, a main nozzle discharging into said chamber, a plurality of wells, an auxiliary nozzle communicating with each of said Wells and effective under predetermined conditions to deliver fuel to said mixing chaine ber, and quills of different characteristics receiving fuel from said Wells and delivering the same adjacent said throttle, one of said quills having its gasoline hole located materially lower than the other.

9. In a carburetor, a mixing chamber, a throttle therein, a main nozzle discharging into said chamber, a plurality of wells, an auxiliary nozzle communicating with each of said wells and effective under predeter- Y mined conditions to deliver fuel to said mixing ch lmber, and quills of diiferent characteristi receiving fuel from said'wells and delivering thev same adjacent said throttle, one of said quills having its gasoline hole located materially lower than the other and having a materially smaller diameter than the other.

In tstimonywhereof I have hereunto set v my hand. v

VICTOR R. HEFTLER.