US1011960A

US1011960A - Carbureter.

Info

Publication number: US1011960A
Application number: US47435409A
Authority: US
Inventors: Alexander George Ionides
Original assignee: JO WALLACE GODDARD
Current assignee: JO? WALLACE GODDARD; JO WALLACE GODDARD
Priority date: 1909-01-26
Filing date: 1909-01-26
Publication date: 1911-12-19
Anticipated expiration: 1928-12-19

Description

A. G. IONIDESQ CARBUBETBR. APPLICATION 21mm zruma, woe.

Patented Dec. 19, 1911.

4 SHEETS-SHEET 1.

Ink eni'o r- A). aria.

Wii'hesk e s;

A. G. IONIDBS.

GARBURBTBR.

APELIGATIQN FILED JAN. 26, 1909.

Patented Dec. 19, 1911.

4 SHEETS-SHEET 2.

)Hn Hum L 1 i 0:. v. 2 I M I M f .n A v NJ 1M 2 0 J 1 J f w Lw i I 17 WNW. Q's es A. G. IONIDBS.

GAEBURETEB.

APPLICATION FILED JLILBG. 190a Patented Dem-19,1911.

umrnn srnrns PATENT OFFICE.

ALEXANDER GEORGE IONIJJES, OF LEICESTER, ENGLAND, ASSIGNOB F ONE-THIRD TO JOSEPH WALLACE GODDARD AND ONE-THIRD TO DENZIL JOHN JARVIS; BOTH OI LEICESTER, ENGLAND.

OARBURETER.

,011,9 0, Specification of Letters rum. P t t d 19, 1911 Application flied January 26, 1909. Serial No. 474,854.

To all whom it may concern:

Be it known that I, ALEXANDER Gnomes Iomons, a subject of the King of England, residing at Leicester, Leieestershire, in Engin the side of the cylinder. The outlet from the mlxing chamber is preferably disposed at one end of the cylinder. The effective portion of the inlet opening ma approland, have-invented certain new anduseful priately be termed the throat of t e carbu 50 Im rovements in Carbureters, of which the. reter inasmuch as the air is sli htly throtfol owing is a SPGClfiCfllllOIl, tled in passin therethrough and to a great This invention relates to carburetors for internal combustion engines and has for its object to construct a carburetor which will automatically maintain a proximately constant the roportions of uel and air in the combustib e m1xture during variations in the engine speed, while the fuel is also delivered into the carbureter in such a way as to insure satisfactory vaporization.

In the present construction the fuel enters 3 is a. longitudinal sectional plan; Fig. 4

is an end elevation looking toward the outlet, and Fi 5 is a section on the line 5-5 of Fig. 2, t e piston in the carbureter being shown in elevation.

Like letters of reference indicate the same parts throu bout the drawings.

According to is invention the mixirg chamber has a yielding member dispos within or forming partof it and so' constructed and arranged as to control" the dimensions of the effective portion of the air inlet opening to the chamber. The fuel jets are so disposed as for example in .a con tinuous row contiguous to ,the air inlet otpeninffg, that variation ofthe dlmensions o the e co tive air opening causes a greater or less number offue'l jets to become operative so I that the number of jets o erative and therefore the amount of fuel issuing from these proportionate to the quantity throu h the opening into jets is always of air which passes the mixing chamber. convenient construction is to make the mixing chamber of cylindrical form the ielding member being. a piston movable wit 'n it so as to uncover a greater or less amount ofthe inlet opening which is arranged as a longitudinal slot The chamber the yielding extent mingle with the fuel before the mixture enters the chamber, which for convenience is" herein referred to as the mixing chamber. Any fuel not vaporized falls on the preferably heated lower surface of the mixin chamber and is there evaporated. imensions of the throat openin are not only variableby the movement 0 the yielding member which may take place antomatically or otherwise but there is also provlded a ositive adjustment whereby the width of t e slot constituting the throat opening may be varied.

It is to be understood that the yielding member or piston does not close or cover any of the fuel passage, but merely restricts the area of the air passage and the fuel opening or openlngs will be acted upon onl by the air or suction in the open part 0 the throat.

At the end of the mixing chamber opposite to the outlet therefrom and on the other side of the yielding member or piston this chamber opens into another chamber conveniently also of cylindrical form. In this chamber is disposed a yielding member conveniently in the form of a piston which is connected to the yielding member in the mixing chamber the second piston having an area larger than that of the piston in the mixing chamber. The two pistons or yielding members are pressed toward the outlet opening by means of a spring or by gravity acting through a cord over a pulley and a weight. The connection between the two pistons is conveniently in the form of a tube so as to allow of communication being established between the portions of the two chambers which are on the sides of the pistons remotefrom each other. This communicating passage is conveniently provided with a non-return valve operative to allow air to flow from behind the larger piston in the direction'of the fuelmutlet from the mixin chamber. The construction is such that w en suction takes place in the mixing member moves so as to uncover or increase the dimensions of the throat opening this movement of the yielding member resulting from the difference of pressure which exists on either side of the throat opening. This difference of pressure results in unequal forces acting on the two pistons which move and enlarge the throat opening until the difference in pressure is reduced to that corresponding with the tension of the spring as the demand from the engine increases. As the opening is enlarged so is the supply of fuel and air increased, the former owing to a greater num ber of fu el jets being brought into operation and the supply of a greater quantity of air naturally resulting from the increased size of the opening. The general dimensions of the throat opening hear such a relation to the areas of the jet orifices that the proportions of fuel and air remain constant throughout the range of variation in the dimensions of the throat o ening effected by the movement of the yiel ing member. The area of each of those few jet openings which are first uncovered may however be made slightly in excess of the remaining jet openin s which are preferably all similar, but I 0 not wish to be understood as limiting the invention to this particular construction as other arrangements will at once suggest themselves which will give a richer mixture when the en ine is running at slow speed or being starte On the air inlet side of the throat opening there may be a passage communicating with the upper part of the float chamber so that when suction is taking place any decrease in pressure in What may be termed the air inlet chamber is communicated to the float chamber thereby allowing unrestrained flow of fuel through those jets which are unmasked by the movement of the yielding member and simultaneously preventing issue of fuel from those jets which have not yet been unmasked.

The jets throu h which the fuel issues may be constructs in some convenient manncr. Passages lead to the jet orifices from a chamber one side of which is formed by a sheet of wire gauze or other suitablefiltering material which in turn lies over a correspondingly shaped opening in the side of the float chamber. The size of the openings in the filter is such that it is not possible for any particle to be carried through the filter which cannot pass freely through the jet orifices.

It is to be noted that the fuel jets are so disposed contiguous to the throat opening that the orifices of all these jets are always open. The terms operative or -ino erative as applied to these 'ets are there ore used not as many way in icating that certain of these jets have their orifices .un covered while others are closed but that according to the position of the yielding member or piston certain of the jets are brought under the influence of the lower pressure or suction existing at or toward one end of the throat opening as the yielding member moves in the manner described. On the other hand those jets which lie along the edge of that portion of the throat opening through which air cannot at the time pass are inoperative byreaso-n of their lying outside the influence of the reduced pressure consequent on the suction from the engine. The cause therefore of the jets becoming operative or inc erative in the sense in which they are so ere described is their being brought within or kept without the range of influence of the engine suction as air 18 drawn through the throat opening and as the dimensions of this 0 ening vary.

In the particular embo iment of the inventiou illustrated a float chamber A is disposed at one side of the mixing chamber B a piece C being disposed between them for the purpose of a convenient construction of the fuel passages between the float chamber and mixing chamber. The mixing chamber B is conveniently formed cylindrical and has mounted co-axially with it and at the opposite end to the outlet.B the auxiliary chamber D. A cover E closes in the top of the float chamber and forms the air inlet E. \Vithin the float chamber A is disposed the usual float F controlling the fuel inlet valve F in some known manner. In the side of the float chamber adjacent to the mixing chamber is formed a lar e opening A which is covered by a sheet 0 metal gauze G, or other filtering material carried by the piece C. This piece C is of wedge shape havin formed in one face a series of grooves C which at the upper end terminate in jet passages 0 formed in the base of the wedge while at the other end these grooves 0 en into a longitdinal slot C. The back or cat chamber side of the wedge piece C is hollow the slot or opening 0 forming a communication between the lower portion of the s ace in the hollow back and the moves C. he gauze G covers in the bee of the wedge piece. The face of the wedge in which'are formed the grooves 0' lies against a flat side B of the mixing chamber B, the grooves C thus forming ducts through which the fuel can flpass to the jets O finding its way from the cat chamber through the gauze G and down through the opening 0 which is situated on a level with the bottom of the float-chamber. To prevent clogging convenient to form the fuel ducts C in this manner and employ the wedge piece C it will be appreciated that these ducts might be formed 1n the face of the flat side B of the mixin chamber or in some other way the piece being formed otherwise than of wedge shape or dispensed with entirely the ducts and filterin gauze or other material being disposed 0t erwise as found convenient between the float chamber and mixing chamber. Also though the jets are here described and shown as plain holes, yet they may be formed in some other manner which will enable jets of sufiicient fineness to be obtained.

The mixing chamber B is conveniently cylindrical with an inlet 0 ening in the form of a longitudinal slot H t is opening being so arranged in relation to the jet orifices that the latter are contiguous tothe opening through its length. Within the chamber B is a yielding member in the form of a piston J having a projection J which fits within the openin H the upper edge or face of this rojection owever being so arranged as to lie just below the plane of the jet openings and thus clear of them. The piston J with its projection J forms a yielding'member or wall of the chamber B such that as the piston moves Within the chamber B the size of the opening H is varied while simultaneously a larger or smaller number of jets become operative or exposed to the air passing in through the throat H.

The auxiliary chamber D practically forms an extension of the chamber B there being free communication between the two chambers. In the auxiliary chamber is dis-- posed a piston K which is connected with the piston J by a tube L, this tube affording a means of communication between that portion of the chamber 13 which lies on the side of the piston J adjacent to the outlet B and the outer end of the auxiliary chamber D which lies on the remote side of the piston K. In this outer portion of the chamber D is disosed a spring L which bears a ainst the ace of the piston K. The end 0 the tube L which carries the piston J is closed by a non-return valve. A convenient construction of the arran ement of this valve and the formation 0% the projection J on the piston J being to extend the end. of the tube L through the piston J as at L This extended portion is screw-threaded and carries a cap J which is formed in one with the projection J. This cap is perforated as at J these perforations being closed by a fla valve J constituting a valve whose outwar movement is limited b'y the curved plate J This guard plate J and the flap valve J are attached to the cap J 2 at some point J 6 which is ad'acent to the opening H this being desirab e so that air drawn through the openingshall not interfere with the operation of the valve. A rod M is attached to the center of the cap J and extends through the tube L out through the head D of the chamber D the rod passing freely through the cylinder head or cover D but fitting so closely as to prevent excessive leakage. The object of this rod is twofold as in thefirst place in the event of any grit or foreign matter getting into either of the chambers B or D and causing the pistons to jam they can be forcibly moved and freed by means of the rod M. Further this rod can be marked or otherwise arranged to constitute an indicator which will show the position of the piston J in the chamber B thus serving to enable the power developed by the engine to be ascertained as will be appreciated from the explanation of the operation of the mechanism'hereinafter given. The general dimensions of the throat opening H can be varied by the adjustment of the plate N which is disposed along the side of the opening 0 posite to the jets. The forward edge N of this plate is conveniently inclined with relation to that edge of the opening H over which it lies so that when this plate N is advanced over the opening H' the general dimensions ofthe latter will be reduced in such a way that the reduction is at first greater toward the end of the opening which is first effective the reduction being graduated toward the opposite end. The plate N is conveniently carried on pins N on which are springs N N over the opening H. The movement of the plate N is however controlled by a screw N operated from the outside of the easing or by some similar means as for example a wire connection with a handle or the like disposed conveniently for the .driver of the engine. The principal use of the plate N is to enable an adjustment of the carburetor to be made with a view to suiting varying atmospheric conditions.

As it is desirable to obtain an increased richness of the mixture at low powers when the effective portion of the opening H is of small dimensions it is convenient to form that end of the opening H adjacent to the outlet B narrower or otherwise constrict it as for example by arranging a plate H which will lie across a portion of this opening and limit the initial area of the opening to the necessary extent. Those *jets of the throat opening are preferably so formed as to allow of the passage of a larger amount of fuel than the remainder or the majority of the jets as is indicated by the varying size of the passage C in Fig.

Free communication is established between the chamber formed by the casing E leadin from the inlet opening E and the inter-i5 of the float chamber A by a hole -tending to. force the edge N of the plate which are adjacent to this restricted pdrtion A so that there will practically be uniformity of pressure on the main inlet open ing side of the throatopening H in the communicating portions of the chambers B and D which lie between. the pistons J and K and in the float chamber A.

The operation of the. carbureter is as fol lows z-.Vv'hen suction from the engine takes place through the outlet opening B for the combustible mixture the pressure in that part of the chamber B which lies on the outlet side of the piston J is reduced, this reduction of pressure being communicated through the valve J J and tube L to the fartherend of the auxiliary chamber D be hind the piston K. This pressure is naturally below that which exists within thecasing E and consequently in the communicating parts of the chambers B and D between the istons J and K so that the diiference of t ese pressures causes movement of the pistons J and K in their respective chambers the movement of the piston J being away from the outlet opening B. This movement causes the projection J of the piston J to open a portion of the throat opening H at that portion of this opening which is adjacent to the outlet B. The jets contiguous to this portion of the opening H are immediately free to deliver fuel into the effective portion of the opening and the suction through the opening causes the fuel to issue from the jets in such a state that a fairly intimate mixture with the air takes piace actually in the throat opening and a thorough admixture is assured. before the combustible mixture passes through the outlet B to the engine. It will be seen that as the rateof suction increases the piston K will be so moved as to increase the dimensions of the inlet or throat opening I-l. Simultaneously additional jet openings are brought into position or allowed to become operative so that the .roportions of fuel and air in the combustib e mixture are maintained constant during variations in the engine speed. It will be appreciated that this variation takes place automatically in accordance with the variations in the ine demand a'nd as a result of these variations in demand and consequent variations in the rate of suction which cause the yielding member or piston to vary the size of the throat opening. Therefore when suction from the engine takes place theefl'ective part of the opening H will be enlarged until the reduction of pressure due to the flow of air through this opening attains the value determined by the tension of the spring. The rate of suction of an engine during each suction stroke usually is not constantand the valve J *is so arranged that the mean vacuum or reduction of pressure in the outer end of the cylinder D is approxim rely that corresponding to the maximum vacuum or reduction of pressure in the engine intake B during the suction stroke of the engine with the result that the effective size of the opening H corresponds approximately to the maximum demand durlng each stroke and therefore allows the engine to draw'in a charge with a mean reduction in pressure for the whole charge considerably below the maximum.

The described arrangement obviously allows a larger char e to be drawn in than would be possible without the use of this valve or some equivalent in the form perhaps of a dashpot. It will be clear that only those jets which are opposite the effective throat are operative since the pressure on the remainder of the jets is the same as that in the float chamber.

Beneath the chamber B or arranged otherwise in relation thereto as ma be found convenient is a jacket B provi ed with inlets and outlets B Heated air ases or water can be passed through this acket if desired so as to vaporize any fuel which has not been properly broken up by spraying from the jets. The float chamber A may also be jacketed to enable it to be heated in the same way.

It will be understood that though in the above described construction the yielding member or piston J in the chamber B is arranged to be operated automatically by the difference of pressure yet in some instances it may be convenient to provide positive operation and consequei'it regulation of the dimensions of the opening H by hand or otherwise than automatically.

The 0 eration of the present carbureter I think is perfectly clear from the specification and drawings for, while the fuel opening or openings always remain open and uncovered, the portion of it, (i. 6., said fuel 0 ening) which is active is determined entire y by the area of the throat opening through which the air is admitted to the engine intake. That portion of the fuel opening which is back of the partitlon J, i. e., remote from the opening in the throat is not exposed to the air passing in through the throat nor to the suction of the engine and, consequently, no fuel is drawn in through the same, the active area of the fuel opening being limited to the open portion of' the throat.

What I claim as my invention and desire to secure by Letters Patent is 1. In a carburetor, the combination of a mixing chamber having a throat ogiening for the admission of air and fuel an a delivery opening for the mixture, a plurality of fuel assages in communication with a source of fuel sup ly, said passages opening near one side of the throat openlng and always remaining open and uncovered, a member movable in the mixing chamber and actmunication with a source of fuel supply,

ing as a partition to cut off or shield from the action of the air passing through the throat opening those fuel passages which are on that side of it remote from the delivery opening, and a piston operated by the suction of the engine for moving the movable member to vary the number of fuel assages which are-exposed to or shielded rom the air passing through the throat.

2. In a carburetor, the combination of a mixing chamber having a throat o ning for the admission of air and fuel an a. delivery opening for the mixture, a plurality of fuel assages in communicationlwith a source of fuel sup ly, said passages openin near one side of e throat openm and a ways remaining open and uncovere a member movable in the mixing chamber and acting as a partition to cut off or shield from the action of the air passin through the throat those fuel passages which are on that side ofit remote from the delivery opening, a piston, operated by the suction of the cu gine and an operative connection between the piston and movable member for movin the movable member to vary the number 0 fuel passages which are exposed to or shielded from the action of the air passing through i the throat.

3. In a carburetor, the combination of a mixing chamber having a throat o ening for the admission of air and fuel an livery openin for the mixture, means for varying the dimensions of the whole throat opening, a plurality of fuel passages in comsaid passages opening near one side 0 the throat openin and always remaining open and uncovered, amember movable 1n the mixing chamber and acting as a partition to cut off or shield from the action of the air passing through the throat those fuel passages which are on that side of it remote from the delivery 0 suing, a piston operated by the suction o the engine and an operative connection between the piston and the movable member in the mixing chamber.

4. In a carburetor, the combination of a mixing chamber having a throat o ening for the admission of air and fuel an a deliveryopening for the mixture, a plurality of fuel passages in communication with a source 0 fuel supply, said passages opening near one side of the throat openin and always remaining open and uncovers an auxiliary or extension chamber in communication with the mixing chamber, a member movable in the mixing chamber and acting as a partition to out off or shield from the action of the air passing through the throat those fuel passages which are on that side of it remote from the deliveryopening, a movable member in the auxilia chamber of greater area than the member in the mixmg chamber, an operative'connection bea detween the member in the mixing chamber and the member in the auxiliary chamber, and a communicating passage between the remote portions of the mixing chamber and auxiliary chamber so that the outer faces of the two members are acted upon by the suction of the en inc.

5. In a car ureter, the combination of a mixing chamber having a throat openlng for the admission of air and fuel and a de livery opening for the mixture, a plurality of fuel assa in communication with a. source 0 f fue supply, said passages opening near one side of the throat opening and always remaining open and uncovered, an auxiliary or extension chamber in communication with the mixing chamber, a member movable in the mixing chamber and acting as a partition to cut off "or shield from the action of the air passing through the throat, those fuel passageswhich are on that side of it remote from the delivery opening, a movable member in the auxillary chamber of eater area than the member in the mixing chamber, an operative connection between the member in the mixing chamber and the member in the auxiliary chamber; a communicating passage between the remote portions of the mixing chamber and auxiliary chamber so that the outer faces of the two members are acted upon by the suction of the engine, and means in the auxiliary chamber tending to move the members in a direction opposite to that in which they are moved by the suction.

6. In a carbureter, the combination of a mixing chamber having a throat o ening for the admission of air and fuel an a delivery opening for the mixture, a plurality of fuel passages in communication with a source 0 fuel supply, said passages opening near one side of e throat opening and always remaining open and uncovered, an

auxiliary or extension chamber in communication with the mixing chamber, a member movable in the mixing chamber and,acting as a partition to cut,ofl' or shield from the action of the air passing through the throat those fuel passages WlllCll are on that side of it remote from the delivery opening, a movable member in the auxiliary chamber of greater area than the member in'the mixmg chamber, an operative connection between the fnember 1n the mixing chamber and the member in the auxiliary chamber, a

communicating passage'between the .remote portions of the mixing chamber and auxiliary chamber so that the outer faces of the two members are acted upon by the suction of the engine, a non-return valve in such .passa go, and means in the auxiliary chamber tending to move the members in a direction opposite to that in which they are moved by the suction.

7. In a carburetnr, ,tlm combinationpf a:

mixing chamber having a throat opening for the admission of air and fuel and a delivery opening for the mixture, a source of fuel supply controlled by a float valve, a plurality of fuel assages communicating with the source of fuel supply, said passages opening near one side of the throat opening and always remaining open and uncovered, an air inlet to the float chamber, a member movable in the mixin chamber and acting as a partition to cut 0 or shield from the action of the air passing through the throat those fuel passages which are on that side of it remote from the delivery opening, a piston operated by the suction of the engine and an operative connection between the piston and the movable member in the mixing chamber, whereby the said member is moved to vary the number of fuel passages which are exposed to or shielded from the air passing through the the throat opening, a member movable in the mixing chamber and acting as a partition to cut off or shield from the action of the air passing through the throat those fuel passages which are on that side of it remote from the delivery opening, and means operated by the suction of the engine for moving the movable member to vary thenum ber of fuel passages which are exposed to or shielded from the action of the air passing through the throat.

9. In a carbureter, the combination of a cylindrical mixing chamber having a throat opening whose length is greater than its breadth formed lengthwise in one side of the mixing chamber for the admission of air and fuel and a delivery opening for the mixture at one end of the cylindrical mixing chamber, a plurality of fuel passages in communication with a source of fuel supply, said passages openin near one side of the throat openin an always remainin 0 on and uncovere and a piston movab e in the mixin chamber and controlled and operated. by t e suction of the engine, such piston being so formed as to act as a partitlon to cut off or shield from the action of the air passing through the throat thos: fuel passages which are on that side of it remote from thedelivery openinl'gl.

10. a carburetor, the combination of :1.

cylindrical mixing chamber having a throat opening whose length is greater than its breadth formed lengthwise in one side of the mixing chamber for the admission of air and fuel and a delivery openin for the mixture at one end of the cylindrical mixing chamber, a plate positioned at one of the long sides of the throat opening and movable over the whole length of the opening to vary the dimensions of the whole of this opening, means for moving this plate and retaining it in various positions, a plurality of fuel assages in communication with a source oi fuel supplyysaid passages opening near one side of the throat opening and always remainin open and uncovered, and a piston mova le in the mixing chamber and controlled and operated by the suction of the engine, such piston bein so formed as to act as a partition to cut 0% 01 are on that side of it remote from the de-- livery opening. 7

11. In a carburetor, the combination of a cylindrical mixing chamber having a throat opening whose length is greater than its breadth formed lengthwise in one side of the mixing chamber for the admission of air and fuel and a delivery opening for the mixture at one end of the c lindrical mixing chamber, a plurality of uel passages in communication with a source of fuel supply, said passages opening near one side of the throat opening and always remaining open and uncovered, a piston movable in the mixin chamber and so formed as to act as a partition to out 01f or shield from the action of the air passing through the throat those fuel passages which are on that side of it remote from the delivery opening, a ciizlindrical auxiliary chamber co-axial with t e mixing chamber and in communication with that end of the latter opposite to the delivery opening, a piston movable within the auxiliary chamber the area of the piston being greater than the area of the piston in the mixing chamber, and a tubular connection between the two pistons so that their outer faces are acted upon by the suction of the en 'ne.

12. n a carburetor, the combination of a cylindrical mixing chamber having a throat opening whose length is greater than its breadth formed lengthwise in one side of the mixing chamber for the admission of air and fuel and a delivery opening for the mixture at one end of the cylindrical mixing chamber, a plurality of fuel assages in communication with "a source of uel supply, said passages opening near one side of the throat openin and always remammg open and uncovere a piston movable in the mixin chamber and so formed as to act as a partition to cut off or shiel'd'from the action as shield from the action of the air passing of the air passing through the throat those fuel passages which are on that side of it remote from the delivery opening, a cylindrical auxiliary chamber co-axial with the mixing chamber and in communication with that end of'the latter opposite to the delivery opening,. a piston movable within the auxiliary chamber the area of this piston being greater than the area of the piston in the mixing chamber, a tubular connection between the two pistons so that their outer faces are acted upon by the suction of the engine, and a non-return valve in the tube.

13. In a carbureter, the combination of a cylindrical mixing chamber having a throat opening whose length is greater than its breadth formed lengthwise in one side of the mixing chamber for the admission of air and fuel and a delivery opening for the mixture at one and of the c lindrical mixing chamber, a plurality of el passages in communication with a source of fuel supply, said passages opening near one side of the throat opening and always remaining open and uncovered, a piston movable in the mixing chamber and so formed as to act as a partition to cut off or shield from the action of the air passing through the throat those fuel passa es which are on that side of it remote from t e delivery opening, a cylindrical auxiliary chamber co-axial with the mixing chamber and in communication with that end of the latter opposite to the delivery openin a piston movable within the auxiliary c amber the area of this piston being greater than the area of the piston in the m1xingchamber, a tubular connection between the two pistons so that their outer faces are acted upon by the suction of the engine, a non-return valve in the tube, and a spring in the auxiliary chamber tending to move the pistons in a direction 0 posite to that in which they are moved by t e suction of the engine.

f 14. In a carburetor, the combination of a cylindrical mixing chamber having a throat opening whose length is greater than its breadth formed lengthwise in one side of the mixing chamber for the admission of air and fuel and a delivery openin for the mixture at one end of the cylin rical mixing chamber, a plurality of fuel passages in communication with a float chamber .to which fuel is supplied, said passages opening near one side of the throat opening and always remaining open and uncovered, a casing with air inlet forming an air chamher over the throat opening, a passage forming a communication between the air chamher and the float chamber, a filter so disposed that the fuel must pass therethrou h on its way from the float chamber to t e passages, means for heating the mixing chamber, a plate positioned at one of the long sides of the throat opening and movable over the Whole length of the opening to vary the dimensions of the whole of the opening, means for moving this plate and retaining it in varying positions, a piston movable in the mixing chamber and so formed as to act as a partition to cut ofl or shield from the action of the air passin through the throat those fuel assages which are on that side of it remote rom the delivery openin ,'a cylindrical auxiliary chamber co-axia with the mixing chamber and in communication with that end of the latter opposite to the delivery opening, a piston movable within the auxiliary chamber the area of this piston being greater than the area of the piston in the mixing chamber, a tubular connection between the two pistons so that their outer faces are acted upon by the suction of the engine, a non-return valve in the tubular connection, and a spring in the auxiliary chamber tendin to move the pistons in a direction opposite to that in which they are moved by the suction of the engine.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

ALEXANDER GEORGE IONIDES.

Witnesses:

WALTER BALL, F. Hoon.

Copies of this patent may be obtained for five cents each, by addressing the 7 Commissioner of Patents,

Washington, D. 0.