US2118038A

US2118038A - Carburetor

Info

Publication number: US2118038A
Application number: US718894A
Authority: US
Inventors: Brodersen Thorwald; William C Dunn
Original assignee: Individual
Current assignee: Individual
Priority date: 1934-04-04
Filing date: 1934-04-04
Publication date: 1938-05-24
Anticipated expiration: 1955-05-24

Description

May 24, 193s.

T. BRoDERsEN f-:T Al. 2,118,038l

cARBUREToR V Filed April 4, 1934 e sheets-sheet 1 immuun May 24, 1938. T. BRDl-:RSEN ET AL CARBURETOR Fild" April 4, 1934 6 Sheets-Sheet 2 May 24, 1938.v TABRODERSEN ET AL 2,118,038

cARBUREToR Filed April 4, 1934 6 Sheets-Sheet 4 v ,y //m May 24, 1938- I T. BRoDERsEN ET AL 2,118,038

GARBURETOR Filed April 4, 1934 `6 sheets-sheet 5 May 24, 1938. T.' BoDERsl-:N ET AL 2,118,038

GARBURETOR Filed April 4, 1934 6 sheets-Sheet 6 'f J5 75g l? J@ l L22 155 /2'0 Zig/.f4 .':z .n 43

Patented May 24, 19.38

, Aulsu'nazo rSTATES 2,11s.oss

caminamos.

Thorwald Brodersen, Park Ridge, and Williamy C. Dunn, Chicago, Ill.

Application April 4, 1934, Serial No. 718,894-

23 Claims. (Cl. 2617-34) l `plying fuel to the supply nozzle 'I'his invention relates to improvements in carburetors for internal combustion engines, and has for one of its objects improved means for creating and maintaining the most desirable mixture proportion for the varying demands of the engine to which the device is connected.

In carburetors where the feedingl of the fuel is due to aspiration or engine suction, considerable difllculty is sometimes experienced in starting the engine in very cold temperaturesby'reason of the inability of the engine to pick up the fuel and carry it into the cylinder. Suchdiillculty occurs by reason of stiffness of motor due to excessive friction created by congealed'oil and also the condition of the gas in extreme cold. Furthermore due to the slowness of the rotation of the motor when attempting to start, due to congealed oil, or weak battery resulting from a hard starting motor, there is a lack of proper velocity of the air over the fuel jet, and it has heretofore been attempted to overcome these difilcultiesl by forcing the fuel directly into the manifold and cylinder.

It is one of the objects of the present invention to provide in a carburetor of this character, im-

proved means whereby a high velocity of air is obtained across the fuel jets when starting the motor under any condition, so that there will be a complete vaporization ofthe gas at ythe fuel jet openings regardless of therate of speed of the motor when starting, and to also provide im.- proved choking means byA the use of which it is possible to cut off the auxiliary air supply and open Wide the fuel'feeding jets or nozzles, and* force the fuel into a stream of high `velocity prifmary' air, with vthe result that the fuel will be thoroughly atomized so that it will be readily drawn or aspirated into the engine cylinder.

lit i-s va'further object of the present invention to provide improved means for automatically dej'liv'ering to the engine a uniform and lean mixture over the complete range of speed when operating under a light load, and a. slightly richer mixture over its complete range of speed when operating underv a heavy load, and' improved means wherebythe fuel mixture will be automatically and readily changed when the load. or requirements of the engine is changed, regardless of the position of the throttle valve, with the resuit that it is possible to acquire the greatest economy when the engine is not required to furnish the maximum power when the engine is operatingunder'its heavy load` A further object is to provide improved means for holding open an auxiliary fuel supply for supstarting the engine.

To the attainment of these ends and the accomplishment of other new and useful objects asv will appear, the invention consists in the features hereinafter more fully described and claimed and shown in the` accompanying drawings illustratjing this invention, and in which Figure 1 is a vertical, longitudinal sectional view of a carburetor of this character constructed in accordance with the principles of this invention.

Figure 2 isa view similar to Figure l, on a smaller scale, and with parts omitted, and showing some of the parts in the position they will assume when engine suction is operating upon thepiston valve to unseat the latter. 4

Figure 3 is an enlarged detail sectional view of the fuelmeteringvalve.

Figure 4 is a view similar to Figure 1, showing the parts in the position which they assume when the choke is being operated and with the throttle about one-third open.

Figure 5 is a detail sectional view as taken -on line 5 5, Figure 7.

Figure 6 is a sectional view taken on line 6 6, Figure 1, with parts omitted. f y

yFigure 6a is a detail sectional view on line Blz-6a. Figure 4.

on line 1 1, Figure 1, with parts omitted.

in choking or Figure 8 is a sectional view taken on line 8-8,

Figure 6, with parts omitted.

Figure 9 is an enlarged detail sectional view of the metering valve and a supplemental control valve for the fuel supply to the nozzle.

Figure 10 is a vertical, sectional view as taken f on line iB lll, Figure 6.

Figure l1 is an enlarged detail view, partly in elevation, partly in section and showing the parts l separated, of the piston valve and the means for` controlling the metering valve.

Figure l2 is a detail sectionalv view taken on line l2 i2, Figure 11.

Figure 13 is an enlarged sectional viewvof a detail.

Figure 14 is a detail sectional view, similar to Figure 6, of a modified form of the invention and with parts omitted. f

Figure 15 is a detail sectional view taken on line I5 |5, Figure 14.

Figure 16 1s a detail sectionn viewv taken on` line iB IB, Figure 14.

Figure 1'1 is a sectional view taken on line I1-I1, Figure 14.

Figure 18 is a detail sectional view taken on line I3I3, Figure 17.

Figure 19 is a detail sectional view taken on line l3-I3, Figure 17.

Referring more particularly to the drawings, the numeral I3 designates a casing having an open chamber I3 in the top thereof closed by a cap member I1 within which latter is arranged a. throttle valve I3. This cap member is provided with a flange I3 having threadedsopenings 23 by means of which the carburetor may be secured in position.

The cap member I1 is removably secured to the top of the casing bymeans of screws 2I, for

a purpose to be hereinafter described.

-The casing I5 is provided with an air inlet opening 22 which communicates with the chamber I3, in ya manner ,to be set forth, and within the chamber I3 is arranged a throat tube 23 of an external diameter considerably less than the internal diameter of the chamber I3, and the throat tube is supported in an opening in the top member 24of a chamber 25, the tube being preferably of an external diameter considerably less than the diameter of the chamber I3, and below the chamber 25 is arranged another .chamber 23.

The linterior of the throat tube y23 is preferably bell shaped as shown in Figure 1, curving inwardly toward a central opening 21 through the bottom thereof, and the throat tube may be of any desired length, the same being ilxedly vsecured in position.

A nozzle member 23 extends through an opening 29 in the bottom of the' chamber 25 and forms a closure for such opening, the nozzle being secured in position by means of suitable fastening devices 33, inJ the form of screws. The nozzle extends through the chamber 25 and is provided with a conical upper end 3|, which projects into the opening 21 in the bottom of the throat tube, and the exterior vdiameter of the nozzle 23 is considerably less than the internal diameter of the chamber 25.

Openings 32 (see particularly Figures 1 and 7) "4 are provided in the wall' 24 between the chambers I3 and 25, and these openings 32 may be of any desired length and form communicating passages between the chamber 25 and the portion-of the chamber I3 in which the throat tube 23 is arranged.

The nozzle 23 is provided with a central passage 33 opening through the bottom thereof, extending lengthwise of the nozzle and terminating short of the apex of the conical end. Branch passages 34 lead from the passage 33 and project through the conical -surface of the end of the nozzle and the passages 34 are arranged at substantially right angles tothe conical surface of the nozzle.

Channels 35 are provided in the conical surface of the nozzle 23, and these passages 35 terminate at substantially the lowerI edge of the opening 21 of the throat tube 23, and thepassages 34 in the nozzleI communicate with and discharge into the channels 35, so that when air currents flow through the channels 35, in a manner to be described and into the throat tube 23, they will ow across the passages 34 and due to their high velocity will entrain or atomize fuel from the passages 34 into the throat tube 23.

The passage 33 in the nozzle is enlarged at its lower end as at 36 and such enlarged portion ex- 'tends through the bottom of the nozzle. -Within this enlarged portion are arranged valve members 31-33, the member 31 being provided with` bers 31--33 are superposed and are held in position by means of screws 43.

The proximate faces of the

valve members

31 and 33 are provided respectively with openings 44-45 and the valve members are preferably cut away as at 43 to form a chamber with which the passages 44-45 communicate. Portions of the peripheries of the valve members 31--33 are also cut away so as/'to form an annular chamber 41, for a purpose to be hereinafter described.

A metering valve 43 co-operates with the valve seats 4I and 42 and this valve increases in diameter from both of the extremities 43-53 to the p'oint 5I of its maximum diameter. which latter is disposed in proximity to,but is spaced for a substantial distance from the extremity 50, and the valve is of such a shape that portions thereof will co-operate with the respective seats 4I- 42 to control the passage of the fuel through the openings 43-33, as will be hereinafter described. The metering valve 43 may be of any desired length and is supported by means of a disc or member 52 which is movable in -the chamber 23,k and the' member 52 is supported by means of rods 53-54 that extend respectively through openings 55-53 in the wall of the chamber 25. .The upper extremities of the rods 53-54 are secured to a piston valve 51 that moves within the charnber I3. This valve 51 is provided with an opening 53 therethrough and which opening communicates with the chamber I3 as well as with the opening in the throat tube 23. p

A sleeve 53 surrounds the throat tube 23 and is slidable thereupon. The wall of the sleeve 53 increases in diameter at the upper end thereof as at 30, and the upper end 4of the sleeve is provided with a flared opening 3i. The sleeve is of a length to project for any desired distance above the top of the throat tube 23 and is adapted to be moved upon and lengthwise of th`e throat tube,

preferably by means of a rock shaft 32 (see particularly Figures 5 and 7) which is journaled in suitable bearings, and to the rock shaft is secured a yoke 33, the arms 34 of which are bifurcated as at 35 to receive lugs or projections 33 that extend from opposite sides of the sleeve 53; A lip or projection 31 extends from the yoke 33 and is so positioned that it will be engaged byv an adjusting screw 33 threaded into the casing and by means of which adjusting screw the extent of movement of the sleeve 53 in one direction may be varied. It will be manifest that by adjusting the screw 33 the movement of the rock shaft 32 for controlling the longitudinal movement of the sleeve53 may be varied and thereby entering the passage 22 will be cut oi from direct isis flow into the chamber I6 between the seat 69 and valve 51 and through the opening 58, but will iow through the openings 32 and through the channels 35 across the fuel jet openings 34 and through the throat tube 23 and opening58 into the chamber I6.

When the piston valve 51 is in the position shown in Figure ,2 with respect to the seat 69 on the sleeve 59, air entering the passage 22 will flow into the chamber I6 through the opening between the piston valve 51 and the seat 69 and through the opening 59. At the same time some of the air will also pass through the openings 32 and thence into the channels 35 across the fuel jet openings 34 and thence through the throat tube 23 and through the opening 58 in the valve 51. l

Encompassing the lower portion of the casing is a bowl 10 which is provided with a chamber 1| formed preferably by depressinga portion of the bottom of the wall of the bowl and which cham- `ber or depression 1| is disposed beneath the disc or member 52. A cleanout opening 12 having a closure plug 13 being provided in the bottom of the chamber 1|. v

Within the bowl 10 is arranged a float 14 which controls a valve 15, the latter controlling thefsupply of fuel to the bowl 10 through the opening 16, a strainer 11 being provided over the opening 18 which is controlled by the 'valve 15.

The chamber 1| has communication with the 4 bowl 10 by means of a passage 19 (see particularly Figure 1) and the top of the passage 19 is disposed below the top of the disc or member 52 when the latter is in its lowermost position, and the duty of the opening 19 is to feed the fuel below the disc 52 to break or overcome any vacuum which might be caused in the chamber 1| when the disc or member 52 is raised by the upward movement of the piston valve 51.

When the disc or member 52 is lowered the fuel will also pass through the opening between the periphery of the disc 52 and the wall of the chamber 26. This opening or space is controlled by means of a ring 80 (see particularly Figures 1, 11, and 13) which surrounds the reduced portion 8| of the disc 52 and is normally seated upon the face or shoulder 82, and the ring is free to move upon the disc, being held in position by means of collars 83-84 which respectively surround the rods 54-53. The ring 80 is oi an internal diameter slightly larger than the diameter of the reduced portion of the disc 52 so as to form a passage therebetween, the ring being maintained in position by being disposed between the portion of the disc 52 beyond the reduced portion thereof and the collars 83,-84. When the disc 52 is lowered the ring 80 will move upwardly, allowing the passage of fluid between the inner periphery of the ring and the periphery of the reduced portion of the disc 52, but when the disc 52 is raised, the ring will be seated to close the passagebc.- tween the inner periphery thereof and the periphery of the reduced portion of the disc. The rod 53 is secured rigidly to the disc 52, the collar 84 encompassing a reduced portion 85 on the rotl 53 so as to abut the shoulder 86 and rest against the upper surface of the disc. The reduced portion of the rod 53 passes through the disc and isl 'secured by means of a nut 81 on the end of the 52 by means of the portion 96 lof the collar 03` passing through an opening 91 in the discand the external diameter of the collar is slightly less than the diameter of the opening. The reduced end 98 of the rod 54 passes through the collar 96 with the shouldered portion 99 abutting the lend of the collar 83, and a nut |00 is threaded upon the end of the reduced portion 98. Likewise, the upper end of the rod 54 is reduced as at |0| to form a shoulder |02 which abuts a washer- |03 that in turn abuts the end of the portion |04 of a' collar |05. The portion |04 passes .loosely through the piston valve 51 witha slight play therearound, and a nut |06 is threaded on the end of the portion |0| with the washer |01 vbetween the nut and the collar |05.

With this construction it will be manifest that in the event the openings 55-56 in the casing are not properly positioned or no't properly alined with respect to the rods 53-54, the rod 54 may be rocked or positioned withrespect to the disc 52 so that it will pass freely through the opening 56. Also the loose connection of the piston valve 51 with the rods 53-54 will permit the piston valve to move laterally so as to properly seat itself upon the surface 69, also to take care of any misalinement of the walls of the chamber I6 in respect to the

rods

53 and 54.

'Ihe chamber 26 is provided with another opening |08 (see Figure 1) in the wall thereof, which communicates with the bowl 10, so that the fuel will iiow through the opening |08 into the chamber 2,6 and from there will flow through the openings 4|42 past the valve 48, into the passage 33, to be'discharged through the passages 34 into the channels 35 Where it will be met by the air currents of high velocityr and atomized into the ,chamber |6 through the throat tube 23 and openthe position shown in Figure 1, and when the motor is starting, it will be seen that the piston valve 51 closesthe direct communicationzbetween the passage '22 and the chamber '|6, with the result that any air entering the passage 22 will flow through the openings 32 to enter the channels v35 to flow across the outlets 34 ofthe passage 33 and into the throat tube, atomizing the fuel. At the same time fuel from the bowl will be entrained'or drawn up inthe passage 33 .and out of the passages 34 by the suction created in the chamber I6, the fuel flowing through the passages 4|42 around the metering valve 48.

As the engine suction increases the piston valve 51 will be raised to `the position shown in Figure 2, and while being so raised will move olf cf the seat 69, thereby producing an opening through which some of the air currents entering the pasder increases, the piston valve 51 will be raised.

`the air passage 22.

4 to a greater extent and the adjustment of the meteringN valve 48 will be commensurate with the movement of the piston valve 51. The screws 43 whichv hold the valve seat members 31-38 in position will serve as stops to limit the up ward movement of the disc 52 as well as the piston valve 51.

AAs the piston valve 51 rises the disc or member 52 will operate as a plunger, causing the fuel in the chamber 26 thereabove to be forced through the openings 4I-42, passages 33-34 into the air channels 35, where it is met4 by the incoming air.

Some fuel will find its way out of opening |98, but the volume of fuel above the disc member 52 is so great 1n chamber 26, that fuel will be forced by the disc 52 through the passages 33-34.

When the engine suction decreases the piston valve, metering valve, and disc member 52 will fall by gravity, and the packing ring 89 will be moved off of its seat 82 so as not to retard the lowering movement of the disc or member 52.

With this construction rit will be manifest that the chamber 1| and the disc 52 operate as a dash pot to dampen or retard a too sudden movement of the piston valve 51 and metering valve 48 in either an opening or closing movement.

When the disc or member 52 is raised by the movement of the piston valve 51, and due to the pressure exerted by the movement of the member 52 in the chamber 26, there would be a' tendency for the fuel to flow through the 'openings 55-56 (see Figure 1) varound the rods 53-54, and unless provisionis made to arrest sucnow the fuel might flow through the openings into In order to prevent this, openings III are provided through the wall of the chamber 25 which communicate with the

passages

55 and 56 and also with the interior of the bowl or tank 19.

With this construction it will be manifest that any fuel which might find its way through the openings 55-56 will flow/through the openings II I back into the bowl 19.

Any suitable means may be provided to raise the sleeve 59 from its normal position (as shown in Figure 1) to a choking position, such forinstance as an arm I|2 provided on the rock shaft 62 (see particularly Figure 10), a swivel member |I3, secured to the end thereof, and to which member ||3 a wire ||4 is connected. The wire leads through a tubular member I I5 to any lconvenient point on the dash board. A lip or projection |I6 is secured to the arm II2 and this projection rests against a plunger I|1 which is normally moved by means of a spring IIB in a direction to contact with the projection and operates to move the arm in a direction to rock the :haft 62 to return the sleeve 59 t`o its normal position. The wire |I4 serves as a choke so that when it is desired to choke the engine and by pulling upon the wire, the arm I I2 will be raised to cause the rock shaft 62 (see also Figure 4) to move in a direction that the sleeve 59 will assume the position shown in Figure 4. During this movement and as the end of the sleeve 59 contactswith the piston valve 51, the latter Will be raised vbythe choking operation, and this in turn will raise the-metering valve 48 to the position shown in Figure 4. At the same time and as the disc 52 rises the fuel will be forced thereby out of the passages 34 into the channels 35 to be met and atomized by the high velocity of air flowing through the channels 35.

During the choking operation the sleeve 59 will be raised andthis'will correspondingly adv just the metering valve 48. However, after partial choking and when the engine is running, suction will be manifested upon the piston rod 51 to raise the same off ofthe seat 69, and at the samev time the metering valve 48 will be further adjusted or opened with respect to the seat 4|-42 to permit an augmented supply of fuel to the passages 33-34. 'I'hen the degree of richness of the fuel can be controlled by the driver.

As soon as the choking operation is completed and the wire ||4 released, the spring I|8 will force the plunger |I1 against the lip or projection I I6 to rock the shaft 62 to return the sleeve to its normal position.

Under heavy loads itis desirable to have a rich mixture and it is also desirable that when the en gine is running free or on a light load, the mixture should be lighter. Therefore, in order to vary the mixture by increasing or decreasing its richness there is provided means for automatically controlling the same, and which means is itself automatically controlled by engine suction. To that end there is provided a chamber ||9 (see particularly Figures 8 and 9) in the wall of the casing, within which a plunger |29 operates.

Communicating with thechamber ||9 is a passage |2I which also has communication with the chamber I6, above the throttle valve I8.

the passage 41, through the openings 44--45 in the valve seat members 31-38, to be discharged through the passage 4| into the passage 33, thereby augmenting the supply of fuel to be discharged through the passages 34. The passage 4| is a determined greater opening than the passage 42 and this greater opening is maintained onv the entire travel of the metering valve 48.

The valve |26 is normally closed by the spring |21 and when the engine is running the suction in the engine cylinder will cause the piston |29 to rise, and the suction will hold the ypiston in a position out of contact with the valve |26. When,

Another means for raising the sleeve 59 so as to raise the seat 69 and also adjusting the metering pin 48 to a fixed position, is shown in Figures 14 to 19, in which there may be provided a shaft l journaled in suitable bearings, with one end thereof projecting into the portion of the chamber |6 in which the sleeve 59 is arranged. On the end of this shaft. |3| is secured eccentrically a cam |32 which operates in a suitable bearing |33 secured to the sleeve. 'I'he other end of the shaft |3| projects for a distance beyond the bearing and has secured to it for movement therewith, in any suitable manner,V such as by means of a portion of the shaft being angular in cross section, to form an angular bearing, an arm |34 by means of which the shaft |3| may be rotated in its bearing. Carried by the arm |34 is a pin or projection |35 adapted to enter sockets |36 in a fixed portion of the structure so as to maintain vthe shaft |3| as well as the eccentric camv |32 and the sleeve 59 in their adjusted positions.

Encompassing the end of the shaft |3| is a sleeve |31 secured thereto in any suitable manner, such as by means of a fastening `in |38. 'I'he sleeve is open at the inner .end and is of a diameter considerably larger than the diameter of the adjacent portion of the shaft |3|. A spring |39 encompasses the shaft with one end seated in the cap |31 and resting against the bottom wall thereof. 'Ihe other end of the spring abuts the arm |34 and tends normally to move it in a direction to cause the pin or projection |35 to enter one of the recesses |36.

It will thus'be manifest that a xed adjustment may be given to the sleeve 59.

In choking the engine, it may be desirable to hold the piston 51 down so that the air entering the passage 22 will not flow directly against the piston to raise the same, and in order to prevent the air from flowing directly from the passage through the opening 58 in the piston 51 and into the chamber I6, and to cause the air to take a downward course through the openings 32 and thence through the passages 35 across the fuel outlets 34.

In order to effect this, any suitable means may be provided, such for instance as a shaft |40 journaled in suitable bearings andA having secured thereto for rotation therewith a cam |4|. The shaft |40 and the cam 4| are so positioned that the cam may b e brought into contact with the periphery of the piston 51, as seen more clearly in Figures 14 and 15, and this cam is adapted to be moved into binding engagement therewith by rocking the shaft |40, preferably through the medium of a rod |42 pivoted to the end of an arm |43, which in turn is secured as at |44 to the shaft |40. A spring |45 is anchored by one end as atV |46 to a stationary part of the structure, and is secured at its other end as at |41 to the shaft |40. 'Ihe normal tendency of the spring |45 is to raise the cam |4| to move the same out of engagement with the periphery of the piston 51 so as to permit the latter to have a free movement. When, however, the rod |42 is operated, the arm |34 will be raised and the cam |4| will be loweredagainst the stress ofthe spring 45, and this will frictionally hold the piston. 51 against movement. As soon as the stress is relieved upon the rod |42, the spring |45 will return the cam |4| to its normal position.

Obviously, the cam and the shaft will operate in a housingA |48, where they will be protected.

At the same time that the piston'51 is held down, which will be sin' starting or choking, means are provided for holding down the pis'- ton |20 to hold the valve |23 down and thereby maintain the fuel passage |25, which communi- Cates with the passage |29, open so as to permit fuel to enter the passage |29 for the purpose of supplying fuel to the nozzle 28 in starting. This may be effected in the following manner. When the engine suction is not sufficient to hold the piston |20 elevated, the piston will` fall bygravity to the position shown'in Figure 16. That is, so that the piston will engage the extremity of the valve |23 and depress the same against the stress of the spring |21, thereby opening the passage |25. When this piston |20 is in this position, which will occur when the piston l51 is in its lowermost position or in the position shown in Figure 15, the piston |20 is held against being raised by engine suction by another cam |49 secured also to the shaft |40. This cam |49 is so positioned that when it is lowered the periphery thereof will contact with the periphery of the piston |20 and will frictionally bind or hold the piston 2Uy against being raised by engine suction. These two pistons51 and |20 may thus be held, locked, so to speak, against being raised by engine suction and when in this position, and the engine is started, a supply of fuel will be delivered to the nozzle until the engine starts to run.

As soon as the engine starts to operate the pistons 51 and |20 may be released by releasing the .strain upon the operating rod |42, and immediately the spring |45 will operate to turn the shaft |40 in a direction to raise the cams |4| and |49 so that they will be moved respectively out of contact with the peripheries of the pistons 51 and |20, after which the pistons 5l and I 20 will operate inthe manner as already described.

With the adjustment means for the sleeve 59 it will be manifest that the sleeve may be raised to any desired extent followed by the rising or adjustment of the metering pin 48, so that more fuel may be supplied while starting and at the same time there will be provided a permanent adjustment for these parts.

The cap member |1 may be provided with additional openings |30, similar to the opening |2|,A

only one of which however is in communication with the chamber ||9, and by being removably secured in position by the screws 2|, it will be manifest that this cap member may be rotat' ably adjustedso as to permit the same to be adjusted to different designs of manifolds.

' If desired, a baille 51St may be provided below the piston 51 and the upper face thereof is disposed below the lowest plane of the surface 69,'

so a's not to interfere with the'seating of the piston valve 61 against the surface '69. The function of said baille is to deflect the air entering beneath the piston valve 51 toward the center of the opening 58, with the result thatthe velocity of theair will not operate or have a tendency to lift or drive the piston valve 51 towards the top of the chamber |6 by the momentum of the air currents,

While the preferred forms of the invention have been herein shown and described, it is'to be understood that various changes may be made in the details of construction and in the combination and arrangement of the several parts, with- 6 in the scope of the claims, without departing from the spirit of this invention.

What is claimed as new is:- 1. In a carburetor, a

nozzle to the mixing chamber, all. of the parts being entirely .housed within the carburetor.

' 2. In a carburetor, a fuel nozzle, means for supplying fuel to the nozzle, a metering valve for controlling the said supply, a mixing chamber, an air supply passage having direct communication with said chamber above the nozzle, means directing a portion of the air from said passage across the nozzle to atomize the fuel therefrom into said chamber, a piston in the chamber above the nozzle and controlled in its operation by engine suction, and a connection between said piston and said valve whereby the operation of the valve will be responsive to` the movement of the piston, said piston also serving as a valve to control the direct connection between the aix` passage and said chamber, the said connection between the piston and the said valve being disposed out of the path of movement of the fuel from the nozzle to the mixing chamber, all of the parts being housed within the carburetor.

3. In a carburetor, a fuel nozzle, means for sup- Y plying fuel-to the nozzle, a metering valve for controlling 'the said supply, a mixing chamber, an air supply passage having direct communication with said chamber above the nozzle, means for directing a portion 'of the air from said passage across the nozzle to atomize the fuel therefrom into said chamber, a piston in the chamber above thenozzle and controlled in its operation by engine suction, a connection between said piston and said valve out of the-path of movement of the fuel from vthe nozzle to the mixing chamber whereby the operation of the valve will be responsive to the movement of the piston, said piston also serving as afvalve to control the direct connection between the air passage and said chamber, and a plunger also responsive in its operation to the movement of said piston for forcing fuel through said nozzle.

4. In a carburetor, a fuel nozzle, means 4for supplying fuel to the nozzle, a metering valve vfor controlling the supply of fuel to the nozzle, an air supply passage for directing air across the nozzle to atomize the fuel therefrom, a'fuel mixing chamber, a piston operating in said chamber above said nozzle and controlled in its operation by engine vair supply passage for suction, a connection between said piston and said metering valve below the latter whereby the operation of the valve will be controlled by the n j m'eans disposed above and concentric with the movement of said piston, and means independent of the said piston and and also responsive in its operation to engine suction andoperating to augment the supply of fuel to the nozzle past said metering'valve.

5. In a carburetor, a supplying fuel to the nozzle, a metering valve for controlling vthe supply of fuel to the nozzle, an directing air across the nozzle to atomize the fuel therefrom, a fuel mixfuel nozzle., means for supplying fuel to the nozzle, a metering valve for i ing a passage having an air passage having for air passage also remote 'from the valve ff i "in'g'"a.nd closing the said direct communication fuel nozzle, means for sponsive to ing chamber, a'piston operating in said chamber above the nozzle and controlled in its operation by engine suction, a connection between said `piston and said metering valve whereby the operation of the valve will be controlled by the movement of said piston, means also responsive in its operation to engine suction and operating to aug-` vment the supply of fuel to the nozzle past said metering valve, the last recited means embodycommunication with the fuel supply and said nozzle, a valve for the last said passage, means. tending normally to move the valve in a direction to close the passage, anda :member reciprocable under the influence of engine suction and adapted when the engine suction drops, to actuate the last said valve against v the stress of the valve `closing means to open the last said passage.

6. In a carburetor, a fuel for supplying fuel thereto, a mixing chamber, direct communication with said chamber above and remote from the nozzle, said air passage also leading across the nozzle to atomize fuel from the nozzle into said chamber, means spaced above and substantially concentric with the nozzle and influenced by engine suction supply nozzle, means for opening and closing the saiddirect communication between the air passage and said chamber, a metering valve for metering the fuel through the nozzle, and an operative connection between the last said means and the said metering valve and out of the pathof the fuel discharged from said nozzle whereby the operation of the metering valve will be responsive to the movement of the former, all of the parts being entirely housed within thecarburetor. i

7. In a carburetor, a fuel supply nozzle, means for supplying fuel thereto, a mixing chamber, an air passage having direct communication with said chamber and remote from the nozzle, said air passage also leading across the nozzle to atomize fuel from the nozzle into said chamber, means disposed above and in alinement with the nozzle and influenced by engine suction for opennozzle, an operative connection between the last said means and the said metering valve housed within the carburetor and disposed out of the path of movement of the fuel from the nozzle to the mixing chamber, whereby the operation of the latter will be responsive to the movement of the former, means embodying a valved passage having communication withthe fuel supply and the nozzle for augmenting the supply of fuel to the nozzle past said metering valve, and means influenced by engine suction for actuating the last said valve to open lthe last said passage.

8. In a carburetor, a'fuel supply nozzle, means for supplying fuel-thereto, a mixing chamber, an air passage having direct communication with said chamber and remote from the nozzle, said leading across the nozzle to atomize fuel from the nozzle into said chamber,

ozzle and influenced by engine suction for openthe fuel through supply and the Anozzle for augmenting the supply of fuel to the nozzle past said metering valve, a cylinder, a piston movable in said cylinder under the influence of engine suction, said piston operating when engine suction drops, to open the valve in the last said passage;v and means for subsequently closing the last said valve.

9. In a carburetor, a fuel nozzle, means embodying a metering valve for supplying fuel to the nozzle; an unobstructed and open throat tube into which the nozzle discharges, a mixing chamber with which the throat tube communicates, an air passage having communication with said chamber and also leading across 'said nozzle, a piston in the chamber spaced above and concentric with the throat tube and influenced in its movement by engine suction, said piston having an opening therethrough in alinement with the end of the throat tube, a plunger with which the piston is connected for forcing fuel into said nozzle, and an operative connection between said plunger and said metering valve for operating the latter, said connection being disposed out of the path of the fuel discharged from the said nozzle, said piston operating to control the communication between the said chamber and the air passage, all of the parts being housed within the carburetor.

10. In a carburetor, a fuel nozzle, means embodying a metering valve for supplying fuel to the nozzle, a throat tube into which the nozzle discharges, a mixing chamber with which the throat tube communicates, an air passage having communication with said chamber and also leading across said nozzle, a piston in the chamber above and concentric with the throat tube and influenced in its movement by engine suction, a plunger below the nozzle, with which the piston is connected for forcing fuel into said nozzle, an operative connection between said plunger and said metering Valve for operating the latter, the last said connection being disposed out of the path of the flow of the fuel from the nozzle to the mixing chamber, said piston operating to control the communication between the said chamber and the air passage, said nozzle being disposed between the piston and said plunger, and means whereby fuel may be supplied on both sides of said plunger.

11. In a carburetor a mixing chamber, an open ended upright throat tube in said chamber. a

fuel nozzle discharging into one end of said tubea..

means for supplying fuel to thev nozzle, an air passage having direct communication with said chamber over the top of said tube, said passage also leading across the end of said nozzle, a sleeve slidable upon and longitudinally of said tube, the upper end of said sleeve forming a valve seat at the top of said tube, a piston movable in said chamber under the influence of engine suction and adapted to co-operate with said valve seat to control the direct communicating passage between the air passage and said chamber, means whereby the movement of the piston will control the supply offuel to the noz.- zle, and means for moving said sleeve lengthwise of said tube to vary the position of said valve seat with respect to the end of said tube, and while the parts of the carburetor remain intact.

.12. In a carburetor a mixing chamber, an open ended upright throat tube in said chamber, a fuel nozzle dischargingv into one end of said tube, means for supplying fuel to the nozzle, an air passage having direct communication with said chamber over the top of said tube, said passage also leading across the end of said nozzle, a sleeve slidable upon and longitudinally of said tube, the upper end of said sleeve forming a valve seat at the top of said tube, a piston movable in said chamber above the throat tube, under the inuence of engine suction and adapted to co-oizierate with said valve sea't to control the direct communicating passage between the air passage and said chamber, means whereby the movement of the piston will control the supply of fuel to the nozzle, means for moving said sleeve lengthwise of said tube to vary the position of said valve seat with respect to the end of said tube and while the parts of the carburetor remain intact, and means operatively connected with said piston for forcing fuel into said nozzle upon the movement of the piston.v

13. In a carburetor a mixing chamber, an open ended throattube Vin said chamber, a fuel nozzle discharging into one end of said tube, means for supplying fuel to .the nozzle, an air passage having direct communication with said chamber. over the top of said tube, said passage also leading across the end of said nozzle, a sleeve slidable upon and longitudinally of said tube, the end of said sleeve forming a valve seat at the top of said tube,.a piston movable in said chamber under the influence of engine suction and adapted to co-operate With said valve` seat to control the direct communicating passage be-` tween the air passage and said chamber, means whereby the movement of the piston will control the supply of fuel to the nozzle, means for moving said sleeve lengthwise of said tube to vary the position of said valve seat with respect to the end of said tube, means operatively connected with the piston vfor forcingl fuel into said nozzle, means for augmenting the supply of fuel to the nozzle, and means also responsive in its action to engine suction for controlling the said augmenting supply of fuel to the nozzle.

14. In a carburetor, a fuel supply nozzle, a. mixing chamber into which the nozzle discharges, a metering valve for controlling the supply of fuel to the nozzle, a fuel supply chamber below the nozzle, a plunger in the last said chamber, said plunger operating to actuate said valve, a piston above the nozzle and responsive in its operation to engine suction, rodsconnecting the plunger and piston, said rods passing through bearings which communicate with said fuel supply chamber, and means comprising passages communicating with and leading from said bearings for discharging from said bearings fuel which may be drawn thereinto.

15. In a carburetor, a fuel supply nozzle. a

mixing chamber into which the nozzle discharges, a metering valve for controlling the supply of fuel to the nozzle, a fuel supply chamber below the nozzle, a plunger in the last said chamber, said plunger operating to actuate said valve, a piston above the nozzle and responsive in its operation to engine suction, rods connecting the plunger and piston, said rods passing through bearings which communicate with said fuel supply chamber, means comprising passages communicating with and leading from said bearings lfor discharging from said bearings fuel which may be drawn thereinto, and a loose packing ring encompassing said plunger, said ring operating to permit lpassage of fuel past said plunger in one direction and preventing passage of the fuel past the plunger in the opposite direction.

16. In a. carburetor a structure embodying a.

fuel nozzle, a piston above and a plunger below and spaced from the nozzle, and rods connecting the piston and plunger, one of said rods being secured to the plunger at one end by a loose connection adapting said rod for lateral movement with respect to the plunger and the other rod for assembling purposes.

17. In a carburetor a structure embodying a fuel nozzle, a piston above and a plunger below and spaced from the nozzle, and rods connecting the piston and plunger, one of said rods being secured byv one of its ends with a loose connection tothe plunger adapting said rod for lateral movement with respect to the plunger and the other rod, and said rods being secured by one of their ends with a loose connection to said piston adapting said piston for free edgewise movement laterally with respect to said rods.

18. In a carburetor, a mixing chamber, an open ended throat tube in the chamber, a fuel nozzle discharging into said tube, an air passage for atomizing fuel from the nozzle, said air passage also having direct communication with said chamber, a sleeve slidable upon and lengthwise of said tube, one end of the sleeve constituting a. valve seat, a piston movable in the chamber Aand influenced in its operation by engine suction, said piston adapted to co-operate with said valve s eat to close the direct communication between the air passage and said chamber, means operatively connected with said piston for metering fuel into said tube, aplunger responsive in its operation to the movement of the piston for forcing fuel into the nozzle, and means for raising the said sleeve with respect to said tube for raising said valve seat and for positively' raising said piston. 1

19. In a carburetor a fuel nozzle, having an inlet opening, valve seat members seated in said opening and having alined openings therethrough to form annular valve seats, said openings at the valve seats being of different diameters, a tapering metering valve member passing through said openings andI co-operating with said seats, and means responsive in its operation to engine suction for controlling the movement of said valve member with respect to said seats, the last said means also operable to force fuel through said openings and into said nozzle.

20. In a carburetor a fuel nozzle, having an inlet opening, valve seat members seated in said opening and having alined openings therethrough to form annular valve seats, said openings at the valve seats being of different diameters, a tapering metering valve member passing through said openings and co-operating with said seats, means responsive in its operation to engine suction for controlling the movement of said valve member with respect to said seats, the last said means also operable to force fuel through said openings and into said nozzle, there being a chamber in said members communicating with said opensaid members kton also serving as a said seats, an annular chamber in communicating with the first said chamber, and means for supplying fuel through said chambers to augment the supply of fuel clischarged past said metering valve and into the nozzle. V

21. In a carburetor, .a fuel nozzle, means for supplying fuel to the nozzle, a metering `valve for controlling the said supply, a mixing chamber, an air supply passage having direct communication with said chamber above the nozzle, means for'directing a portion of the air from said passage across the nozzle to atomize the fuel thereings between from into said chamber, a piston in the chamberb controlled in its operation by engine suction, a connection between said piston and said valve whereby the operation of the valve will be responsive to the movement of the piston,- said pisconnection between chamber,v and means controllable at will and movable into and out of contact with said piston for locking said piston against movement in either direction.

22. In a carburetor, a fuel nozzle, means for supplying fuel to the nozzle, a metering valve for controlling the supply of fuel to the nozzle, an air supply passage for directing air across the nozzle to atomize the fuel therefrom, a fuel mixing chamber, a piston operating in said chamber and controlled in its operation by engine suction, a connection between said piston and said metering valve whereby the operation of the valve will be lcontrolled by the movement of said piston, means also responsive in its operationto engine suction and operating to augment the supply of fuel to the nozzle past said metering valve, and means controllable at will and individual to the piston and the last said means and respectively movableinto and out of engagement therewith, for maintaining them against movement in either direction.

23. In a carburetor, a fuel nozzle, means for supplying fuel to the nozzle, a metering valve for controlling the supply of fuel to the nozzle, an air supply passage for directing air across the nozzle to atomize the fel therefrom, a fuel mixing chamber, a piston operating in said chamber and controlled in its operation by engine suction, a connection between said piston and said metering valve whereby the operation of the valve willv be controlled by the movement of said piston, a valve to augment the supply of fuelk to the nozzle past the metering valve, means embodying a piston lresponsive in its operation to engine suction and operating to open the last said valve, means embodying dlvidual to said pistons for locking them against operation by engine suction, and means for controlling said locking elements atwll.

THORWALD BRODERSEN. WILLIAM C. DUNN.

valve to control the direct the air passage and said locking elements in-Y