US1412000A

US1412000A - Kerosene carburetor

Info

Publication number: US1412000A
Application number: US111336A
Authority: US
Inventors: Jr John J Hawxhurst; Edward F Nicolai
Original assignee: Individual
Current assignee: Individual
Priority date: 1916-07-26
Filing date: 1916-07-26
Publication date: 1922-04-04
Anticipated expiration: 1939-04-04

Description

1.1. HAWXHUHSTI hi., AND E. F. NICOLAI. KEROSENE CARBURETOR. APPLICATION man JuLY 26. 191s.

1 P1 -12,000, Patented Apr. .4, 1.922.

a SHEETS-'SHEET 1.

1.1. HAWXHURST,JH.,'AND E. F. NICOLAI.

KEROSENEYCARBURETOR.' APPLICATION FILED `Juul 26. me.

Patented Apr. 4, 1922.

3 SHEETS-SHEET 2.

Im/e nto rsf:

71m llttorneg 3 SHhETS-SHEET 3.

Patented Apr. 4, 1922.

lll

KEROSENE CARBURETOR.

AFFLiCATION FILED JULY 26,1916.

UNITED STATE-s PATENT orifice.

JOHN' J. HAWXHURST, JR., 0F BROOKLYN, AND EDWARD F. NICOLAI, OF PORT WASH- IN'G'JON,A NEW YORK.

KEROSENE CARBURETOR.

Application ined July v26,

To all whom it may conce-rn:

Be it known that we, JOHN J. HAwxHURsT, Jr., and EDWARD F. NIooLAI, residents, respectively,'of Brooklyn, in the county of Kings and State of New- York and Port lVashington in the county of Queens and State of New York both citizens of the United States, have invented certain new and useful Improvements in Kerosene Carburetors, of which the following is a specification.

Oui; invention relates to ca-rburetors designed for use with internal combustion engines; and more particularly to that type or class of carburetors designed for use with self-propelled vehicles, and in which a. preliminary mixture containing too much fuel to burn properly is irst formed by the atomizing action lof a current of air caused to ow past a fuel supply nozzle by the suction or vacuum producing action of the engine, which rich preliminary mixture is afterward diluted to produce a proper combustible mixture by a further quantity of air admitted or permitted to flow into a suitable mixing chamber wherein the preliminary" mixture and the diluting air are thoroughly mixed with one another; the supply of additional air being regulated and controlled by an automatically operating auxiliary air valve also dependent for its operation upon the suction action of the engine.

An object of our invention is lto provide a carburetor in which the outlet passage leading to the engine is permanent-ly open and uncontrolled, as by a throttle valve, and in which the suction or vacuum producing action of the engine acts at all times directly upon the elements which cooperate to form the rich preliminary mixture irrespective of whether or not additional air to dilute the mixture thus formed is being permitted to iiow into the mixing chamber; whereby the suction of the engine is at all times effective to secure a suHicient supply of fuel, and a proper atomization thereof, irrespective of speed andv load conditions under which the engine is operating and irrespective of whether or not additional air is ,being admitted to the mixing chamber by the auxiliary air valve.

A further object of our Iinvent-ion is to provide a carburetor in which the speed of4 the engine is regulated by the valve which Specification of Letters Patent.

p Patented Apr. 4, 1922. 1916. serial No. 111,336. l

rpermits the admission of additional or dilutwhen it is running without load, or idling, isA

secured; to provide a carburetor in which the extent of opening movement of the auxiliary air valve may be controlled manually, and independently of the means concerned with the automatic operation of said valve, so that throttling and the speed of the engine may be regulated and controlled by means of said valve; to provide a carburetor in which the adjustment necessary to secure continuous and uniform operation of the engine atlow speed, as when it is running without load, may be more readily made than heretofore; to provide a carburetor which is simple in construction and effective for the purpose for which it is designed, and one in which the combustible mixture will be more nearly uniform throughout the entire range of speed and load conditions of the engin-e with which itis used, than has been the case in prior carburetors of the type to which our invention relates; and to otherwise. improve upon and enhance the eiciency of carburetors designed for use with internal combustion engines. v

With the above and other objects of invention in view, our invention consists in the improved carburetor for internal combust-ion engines illustrated in the accompanying drawings, described in the following specification, and particularly claimed, and

is illustrated, and wherein the same refer- I ence numerals are employed to designate like parts in the several figures;

- Figure 1 is a view showing a section of our improved carburetor taken upon a vertical central plane indicated by the line 1-1,

Figure 2 Figure 2 is a view showing the same in Plan.;

Flgure 3 1s a view showlng a section taken upon a horizontal plane indicated by the line 3 3, Figure l;

Figure 4 is a view showing a section taken upon horizontal planes indicated by the broken line 4 4, Figure 1;

Figure 5 is a View showing a section taken upon a vertical transverse plane indicated by-the line 5 5, Figure 4; and v Figure 6 is a fragmentary View employed to illustrate certain features of the fuel supply controlling valves of our carburetor, and showing a slightly modified arrangement of some of the elements thereof.

In the drawings, and referring particularly to Figure 1, the reference numeral 6 designates the exterior casing of our improved carburetor which serves as a support for, or which contains the various elements which cooperate to produce a combustible mixture suit-able for use by the engine with which the carburetor is used; and 7 designates a mixin chamber located within t-he casing and wlthin which chamber, in the normal operation of the engine, a rich preliminary mixture of air and fuel is mixed with additional air entering through a port or ports 8 and thus diluted to form a mixture containing the proper quantities of air and fuel for use in the engine; the combusti ble mixture flowing from the casing through an outlet passage 9 and to the engine through a suitable conduit not shown, as will be understood. This casing is provided with a. transverse wall or partition 10 having an opening 11, and the same is shown as made up of separate upper and lower sections secured together by means of lugs 12 through which screws 13 extend, see Figure 4, to thereby provide a unitary casing; although this is a detail of construction employed for convenience in makin the casing, rather than an indispensable feature of our inventlon, as will be appreciated from the concludmg claims wherein the essential features ofour invention are pointed out and specified.

Located within the lower portion of the casing 6 is a comparatively large. air chamber 14 having a top wall 15 spaced apart from and extending approximately parallel with the transverse wall 10, and the said lower portion is provided with a double side vwall whereby an interior heating chamber 16 is provided which includes the space bebetween the partition 1() and top wall l'and surrounds the air chamber 14, and through which heating chamber a heating medium, such as exhaust gases from the engine, may be made to liow by means of suit-able conduits connected with passages 17 leading into said heating chamber, the heating chamber being divided by a Suitable partition 18 in order to secure a proper circulation of the heating medium about the air chamber, as will be appreciated. The air chamber is shown as open at its lower end, and said lower end as closed by a suitable cover 19, having openings 20 through which air enters the chamber; and which cover serves as a support for certain of the elements concerned with the supply of fuel to the carburetor, as will hereinafter appear.

The top wall' l5 of the air chamber 14 iS spaced apart from the transverse wall 10 as shown, from which it is obvious that the heating medium employed will flow between these walls and across the top of as well as around the air chamber; andthe said top wall is provided with an opening 21 located in line with the opening 11 in the wall 10. Extending across the space between these walls and having its ends lying within the openings aforesaid in said walls is a tubular heating member ast the exterior of which the heating me ium flows, and through which the rich preliminary mixture flows on its way to the mixing chamber, whereby the Said preliminary mixture is heated on its way to the mixing chamber and a more perfect vaporization of the liquid fuel thus secured; said heating member being shown as comprising a series of separate tubes 22 the ends of which are secured in

heads

23, 24, lying within the openinvs 11 and 21, and the lower of which is in threaded engagement with the latter of said openings, whereby the heater as a whole may be removed for the purpose of cleaning the same; said heater having also a central tube'25 through which the stem or shank of a fuel valve 26 extends. It therefore follows that the preliminary mixture in fiowing through the heater is divided into a plurality of separate and independent st-reams, and that the heating me-v dium flows around and between said tubes, whereby an veffective heating of the preliminary mixture 'and thorough vaporization of I the liquid fuel is secured.

The air which is mixed with the liquid fuel to form t-he rich preliminary mixture herein referred to flows through the openings 20 and into the compara-tively larve heated air chamber 14 wherein a. mnsiderabe reservoir of heated air always exists; and from said chamber through the tubes 22 of the preliminary mixture heater and into the mixlng chamber 7; the elements enumerated constituting a vertically extending permanently open and uncontrolled primary air inlet passage leading into the mixing chamber, as will be understood. Thisv passage is preferably contracted to provide a. venturi at 27 formed in a neck 28 depending from the

top wall

15, and 29 designates the fuel supply nozzle of our imp roved carbureter through which liquid fuel 1s supplied to the stream of air as it flows to the mixing chamber and which fuel is atomized by the action of the air as it flows past the nozzle, as will be understood.

The opening 11 extends through an annular portion or neck 30 extending upwardly from the partition 10 and having an annular valve seat 31 at its upper end and surroundingr the upper end of the primary air inlet passage above referred to; and 32 designates a vertically movable auxiliary air inlet valve, the same vhaving a seating surface 33 adapted to cooperate with the valve seat 31 to interrupt the flow of air through the ports 8 and into the mixing chamber when the valve is in its lowermost position shown in Figure 1, and to permit diluting air to flow into the mixing chamber when said valve occupies a higher position and its seating surface lis out of contact with the valve seat 31; the space between the valve seat 31 and the seating Surface 33 when the said seating surface is out of contact With the valve seat, the adjacent .Space within the carburetor casing, together with the ports 8 forming an auxiliary air inlet passage controlled by the air valve and leading into and through which air may flow to the mixing chamber, as will be understood. The air valve is provided with a cross bar or spider 34 to which the upper end of the shank or stem of the fuel valve 26 is connected, so that the fuel valve is carried by and pai-takes of the movements of the auxiliary air inlet valve.

The inner surfaceof the carburetor casing is formed with two concentric portions 35, 36, of different diameters, and the periphery of the auxiliary air-valve 32 is provided with two concentric portions 37, 38, of different diameters adapted to move in contact with the concentric portions of the casing, whereby an air chamber 39 is provided between the valve and casing; and 40 designates a passage in the wall of the air valve and through which the air chamber 39 is placed in communication with the interior of the carburetor. Means are provided for regulating the action of the air chamber 39. the same comprising an air inlet passage 41 having a check valve 42 opening toward the air chamber, the flow of. air through the passage 41 being controlled by an adjustable needle valve 43.

The auxiliary airvalve 32 is moved upward automatically and by the suction of the engine which reduces the pressure within the air chamber by withdrawing air therefrom through the passage 40, thus permitting atmospheric pressure to act upon the enlarged lower portion 38 of the valve. This upward movement will take place rapidly if the flow of air through the air inlet passage 41 is restricted by the vvalve 43,

and slowly if the air may flow freely through said passage, all as explained more fully in our application for patent for carburetor for internal combustion engines, filed upon March 3, 1916, Serial Number 81,865, which, since the filing of this application, has resulted in United States Letters Patent No. 1,210,799, vdated January 2nd, 1917; and in which, among other features, anv auxiliary air valve and an air chamber similar to the one herein illustrated, is claimed.

Means are provided in our improved carburetor for limiting the extent of upward movement of the air valve due to the suction of the engine, and for positively moving said valve downward and in vopposition to the suction to thereby reduce the supply of diluting air and thus throttle the supply of combustible mixture to the engine, said means being shown'as comprising an oscillating shaft 44 supporting in bearings provided in thecarburetor casing and operated through an arm 45 from any suitable point and through suitable connections, said shaft carrying a cam 46 which engages a Stop member 47 pivotally supported at 48 from the casing and so located as to engage or be engaged by the upper end of the air valve,

all as shown in Figure 1 of the drawing; from which it follows that upward movement of the air valve will be arrested when the stop member is swung upward and into Contact with the cam, and that the cam may be rotated to force the valve downward so as to cut off to a greater or less extent the flow of air through the auxiliary air inlet passage and into the mixing chamber.

In Figure 1, the various parts are shown in the positions whichthey occupy when the engine is to be started and, the supply of diluting air to the mixing chamber being cut olf because of the engagement of the seating surface 33 with the valve seat 31, the entire suction or vacuum producing action of the engine will act directly at the fuel supply nozzle and produces a'strong and effective atomizing action at said nozzle; whereas, if the outlet passage 9 were provided with a throttle valve to be partly closed at starting, the vacuum produclng action of the engine would be for the most part expended in producing a flow past the throttle valve, with the result that the velocityof air past the fuel supply nozzle 'i would be reduced to such an extent as to seriously interfere with if not entirely defeat the atomizing action of the said air.

At starting, then, the mixture supplied to the engine is formed by the air which enters through the primary air inlet passage, and such air flows past the fuel supply nozzle at high velocity, because of the direct action of the suction produced by the engine at the fuel supply nozzle due to the absence of a vthrottle valve in the outlet from the carburetor, from whichy it follows that a copious and suicient supply of fuel for starting is secured and that the fuel` is thoroughly `atomized and vaporized.

After the engine has been started the cam 46 is rotated in order to permit the stop member 47 to rise and the engine to attain its normalspeed, during which increase in speed the air valve moves upward due to the partial vacuum within the carburetor casing as hereinbefore explained, and an increasing quantity of air is permitted to flow past the auxiliary air valve and into themixing chamber, as will be understood.

The adjustment of the carburetor relative to the engine is such that the air valve follows and its upper end keeps in contact with the stop member 47 as the cam 46 is moved, so that the position of the cam always determines the maximum speed of the engine. lf, however, it isdesired to reduce the speed of the engine, the air valve is moved downward by the cam 46 acting through the stop member 47, whereby the supply of diluting air to the mixing chamber is reduced and thesupply of combustible mixture to the engine 1s throttled. This action, however, 1s not accompanied by such a change in the mixture supplied to the engine as to impair its burning qualities as because of an insuflicient fuel supply, faulty atomization, or otherwise, for the reason that in our carburetor the suction of the engine always acts directly at the fuel nozzle as the throttling is accomplished by the auxiliary air valve, and the throttling operation is accompanied by-an increase rather than by a reduction of the supply of fuel, and by a more vigorous rather than by a diminishing atomizing action because of the greater velocity of the flow of the stream of air a-st the fuel supply nozzle at such times. Finally, should the speed of the engine decrease for any reason, as when the vehicle encounters a hill, or should the load upon the .engine be increased, the suction action within the carburetor casing will be reduced and the air lvalve will move downwardly, thus automatically reducing the supply of diluting air and at the same time securing an increase in the velocity of flow of the stream of air past the fuel supply nozzle. which action will result in a mixture having a larger proportion of fuel the combustion of which will tend to increase the power of the engine and to cause it to resume its former speed.

The auxiliary air inlet ports 8 are preferably located adjacent the upper end of the primary air inlet passage. and, in order to provide for a heated supply of diluting air which may sometimes be desirable notwithstanding the heating to which the preliminary mixture is subjected, al heating jacket is provided which extends from the said air inlet ports downward to the lower end of the carburetor casing; which jacket is spaced apart from the casing and is open at its lower end whereby an annular air passage 49 is provided, and whereby the diluting air will be heated by the outer wall of the heating chamber 16 as it flows through the passage above referred to. The jacket here contemplated is preferably made of two similar parts or sections, 50, 50, so shaped as to tit about the carburetor casing, as shown, and said parts are held together and u on the casing by means of screws 51 exten ing through lugs formed upon the sections, whereby a heatingA jacket is provided which may be readily attached to or removed from the carburetor.

The cover 19 for the heated air chamber 14 is provided with a fuel supply passage 52, and with a downwardly extending interiorly treaded tubular extension or supporting member 53, the interior of which communicates with said fuel supply passage, as shown; and the referencev numeral 54 designates a tubular member in threaded engagement with the interior of said extension and extending up into the air chamber and terminating adjacent the venturi opening f2.7.v

The fuel supply nozzle 29`is located within and movable longitudinally of the tubular member 54, to which end said nozzle isprovided with a depending portion operatively connected with a lrotary nozzle adjusting member 55 in threaded engagement with the interior of the extension 53; said nozzle ad justing member having an operating arm 56, and suitable packing Ibeing provided therefor, as shown.

The urpose ofthe mechanism for vertically a( justing the fuel supply nozzle above explained is to enablefthe carburetor to be so adapted to the engine with which it is used as to produce a mixture containing such quantities of air and fuel that the engine may be readily started when the auxiliary air inlet valve is in its lowermost position, as hereinbefore explained, and to produce a mixture suitable for use when the engine is running without load, or idling; as well as to also provide an adjustment whereby a proper supply of fuel may be Asecured when the engine is operating 4under normal speed and load conditions. and whe i diluting air is being admitted to the mixing chamber; it being obvious that downward movement of the fuel supply nozzle will be accompanied by an increase in the quantity of fuel supplied whatever may be the position of the air valve and fuel valve carried thereby, and vice versa.

The liquid fuel supply passage 52 communicates with a fuel passage 57 formed in the bottom wall of a fuel 'reservoir the interior of which is divided by a partition 59 into two compartments; which compartments communicate with the passage 57 through

ports

60, 61, the fiow through which is controlled by vertically moving

reciprocating fuel valves

62, 63, having upwardly extending stems 64, 65, which extend through the top wall or cover 66 of the fuel reservoir and are provided with

grooved collars

67, 68.

Supported from the top wall or cover of the reservoir 58 is an oscillating fuel supply valve operating member having an arm 69 through which it may be operated from a distance and forked valve operating arms 70, 7l, which engage the collars 67,'68, aforesaid; from which it will be obvious that when said lever and valves are in the positions shown in Figure l, fuel will flow from the right hand compartment of the fuel reservoir, while if the operating'aiin 69 be moved to the right the valvev 63 will be moved so as to close the port 61, and the valve 62 so as to open the port 60, whereupon fuel will be supplied from the left handcompartment of the fuel reservoir.

In order to hold the valve operating member and the fuel valves operated thereby in either of the extreme positions assumed by said parts the valve stems 64,

valve downward into firm contact with its seat and holding it in that position until the valve operating member is operated to seat the other valve, as will be understood from Figure-6 of the drawings. In this Figure 6 the housings 74 are shown as arranged at right angles to the positions which they occupy in the other figures, see particularly Figure 2, in order to better illustrate. the construction and operation of the valve op erating mechanism as a whole in a single figure; the figure in question thus showing .a modified arrangement of the housings upon the cover 66 of the full reservoir.

The two compartments of the fuel supply reservoir are supplied from any suitable Sources with two kinds of fuel, such as gasoline and kerosene, the former being used at starting and the latter after the engine hasbeen started, as hereinbefore explained; said fuels being supplied through

inlet conduits

75, 76, and the fiow through said conduits being controlled

by'fioats

77, 78, withh in the chambers, as shown and as is usual in carburetors of the type to which our inven tion relates.

Having thus described and explalned our a permanently openand uncontrolled outlet passage leading from said mixing chamber; a nozzle through which fuel is supplied to said primary air inlet passage; a

suction operated auxiliary air valve adapted to control the flow of air through said auxil' iary air inlet passage; and means for regulating the extent of movement of said auxiliary air Valve.

2. In a carburetor of the class described,

'a suitable casing having a mixing chamber,

a permanently open and uncontrolled pri- .mary air inlet passage leading into Asaid mixing chamber, an auxiliary air inlet passage leading into said mixing chamber, and a permanently open and uncontrolled outlet passage leading from said mixing chamber; a nozzle through which fuel is supplied to said primary air inlet passage; a suction operated auxiliary air valve adapted to control the flow of air through said auxiliary air inlet passage; means for regulating the extent of movement of said auxiliary air valve; and a fuel valve connected with and operated by said auxiliary air valve and adapted to control the flow of fuel through said fuel supply nozzle.

3. In a carburetor of the class described, I a suitable casing having a. mixing chamber, a permanently open and uncontrolled primary air inlet passage leading intosaid mixing chamber, an auxiliary air inlet passage leading into said mixing chamber, and a permanently open and uncontrolled outlet passage leading from said mixing chamber; a nozzle located within said primary air inlet passage; a suction operated auxiliary air valve adapted to regulate the supply of airto said mixing chamber; and a fuel valve connected with and operated by said auxiliary air valve and adapted to control the flow` of fuel through said fuel supply nozzle;

4. In ay carburetor of the class described, a suitable casing having a mixing' chamber, a vertically extending permanently open and uncontrolled primary air inlet passage leading into saidmixing chamber, a series of auxiliary air inlet ports through which air may flow into said mixing chamber, and a permanently open and uncontrolled outlet passage leading from said mixing chamber; a vertically movable annular air valve located within said casing and adapted to regulate the supply of air to said mixing chamber; a fuel supply nozzle located within said primary air inlet passage; and a fuel vvalve carried by said auxiliary air valve and adapted to control the flow of fuel through said fuel supply nozzle.

5. In a carburetor of the. class described, a suitable casing having a mixing chamber, a vertically extending permanently open and uncontrolled primary air inlet passa-ge leading into said mixing chamber, a series of auxiliary air inlet ports through which air may flow into said mi-xing chamber, and a permanently open and uncontrolled outlet passage leading from said mixing chamber; a vertically movable suc-tion operated annular air valveI located within said casing and adapted to regulate the supply of air to said mixing chamber; means for regulating the extent of upward movement of said auxiliary air valve; a. fuel supply nozzle located within said-primary air inlet passage; and a fuel valve carried by said auxiliary air valve and adapted to control the flow of fuel through said fuel supply nozzle.

6. In a carburetor of the class described, a suitable casing having a mixing chamber, a vertically extending permanently open and uncontrolled primary air inlet passage -leading into said mixing chamber, a series of auxiliary ail' inlet ponts through which air may How into said mixing chamber, and a permanently open and uncontrolled outlet passage leading from said mixing chamber; a vertically movable suction operated annular air valve located within said casing and adapted to regulate the supply of air to said mixing chamber; an adjustable stop member adapted to limit the Aextent of up# ward movement of said auxiliary air valve; a fuel supply nozzle located within said primary air inlet passage; and a. fuel valve carried by said auxiliary air valve and adapted to control the flow of fuel through said fuel supply nozzle.

7. In a. carburetor of the class described,

a suitable casing having a mixing chamber, a vertically extending permanently open and uncontrolled primary air inlet passage leading into said mixing chamber, a series of auxiliary air inlet ports through whic-h air may flow into said mixing chamber, and a permanently open and uncontrolled outlet passage leading from said mixing chamber; a vertically movable annular air valve located within said casing and adapted to reg-` ulate the supply of air t0 said mixing chamber, the inner surface of said casing having concentric portions of different diameters, and the periphery of said air valve having also concentric portions of different diameters adapted 'to move in contact with the concentric portions of said casing, whereby an air chamber is provided between said valve and casing; a fuel supply nozzle locaited within said primary air inlet passage; and a fuel valve carried by said auxiliary air valve and adapted to control the How of fuel through said fuel supply nozzle.

8. In a. carburetor of the class described, a suitable casing having a mixing chamber` a vertically extending permanently open and uncontrolled primary air inlet passa-ge leading into said mixing chamber, a series of auxiliary air Ainlet ports through which air may flow into said mixing chamber, and a permanent-ly open and uncontrolled loutlet passage leading from said mixing chamber; a. veitically movable annular air valve located within said casing and adapted to regulate the supply of air to said mixing chamber, the inner surface of said -casing having concentric portions of different diameters, and the periphery of said air valve having also concentricI portions of different diameters adapted to move in contact with the concentric portions of said casing` whereby an air chamber is provided between said valve and casing; manually operable means adapted to regulate the extent of upward movement of said auxiliary air valve; a fuel supply nozzle located within said primary air inlet passage: and a fuel valve carried by said auxiliary air valve and adapted to control the flow of fuel through said fuel supply nozzle.

9. In a carburetor of the class described, a suitable casing having a mixing chamber, a vertically extending permanently open and uncontrolled primary air inlet passage leading into said mixing chamber, a series of auxiliary air inlet ports through which air may flow into said mixing chamber, and a permanently open and uncontrolled outlet passage leading from said mixin chamber; a vertically movable annular air valve located within said casing and adapted to regulate the supply of air to said mixing chamber, the inner surface of said casing having concentric portions of different diameters, and the periphery of said air valve having also concentric portions of different diameters adapted to move in contact with the concentric portions of said casing, whereby an air chamber is provided between said valve and casing; means for regulating the action of said air chamber; means for regulating the extent of upward movement of said auxiliary air valve; a f-uel supply nozzle located within said primary air inlet passage; and a fuel valve carried by said auxiliary air valve and adapted to control the flow-of fuel through said fuel supply nozzle.

10. In a carbureter of the class described, a Suitable casing having a mixing chamber, a vertically extending permanently open and uncontrolled primary air inlet passage leading into said mixing chamber, a series of auxiliary air inlet ports through which air may flow into said mixing chamber, and a permanently open and uncontrolled outlet passage leading from said mixing chamber; and a vertically movable suction operated annular air valve located within said casing and adapted to regulate the supply of air to said mixing chamber; the capacity of said primary air inlet passage being suiiicient to furnish the air necessary for forming a combustible mixture for the engine with which the carburetor is used when the engine is running at low speed.

11. In a carburetor of the class described, a suitable casing having a mixing chamber, avertically extending permanently open and uncontrolled primary air inlet passage leading into said mixing chamber, a series of auxiliary air inlet ports through which Vair may flow into said mixing chamber, and a permanently open and uncontrolled outlet passage leading fromsaid mixing chamber; a vertically movable annular air valve located within said casing and adapted to regulate the supply of air to said mixing chamber, the inner surface of said casing having concentric portions of different diameters, and the periphery of said air valve having also concentric portions of different diameters adapted to move in contact with the concentric portions of said casing,l

whereby an air chamber is provided between said valve and casing; and means for regulating the extent of upward movement of said auxiliary air valve.

12. In a carburetor of the class described,

a suitable casing having a mixing chamber,

a vertically extending permanently open and uncontrolled primary air inlet passage leading into said mixing chamber, a series of auxiliary air inlet ports through 'which air may flow into said mixing chamber, and a permanently open and uncontrolled outlet passage leading from said mixing chamber;

a vertically movable annular air valve located Within said casing and. adapted to regulate the supply of air to said mixing chamber','the inner surface of said casing having concentric portions of diiferent diameters, and the periphery of said air valve having also concentric portions of different diametersadapted to move in contact with the concentric portions of said casing, whereby an air chamber is provided between said valve and casing; means for regulating the action o f said air chamber; and means for regulating the extent of upward movement of said auxiliary air valve.

13. In a carburetor of the class described, a suitable casing 'having a Amixing chamber, a vertically extending permanently open and uncontrolled primary air inlet `passage leading into said mixing chamber, a series of auxiliary air inlet ports located adjacent the upper end of said primary air inlet passage and through which air may .flow into said mixing chamber, and a permanently open and uncontrolled outlet passage leading from said mixing chamber; an annular a vertically extending permanently open and uncontrolled air inlet passage leading into said mlxlng chamber, a serles of auxiliary air inlet ports located adjacent the upper.

end of said primary air inlet passage and through which air may flow into said mixing chamber, and a permanently open and uncontrolled outlet passage leading from said mixing chamber; an annular valve seat surrounding the upper end of said primary air inlet passage; a vertically movable suction operated annular air valve located within said casing and having an annular seating surface adapted to co-operate with said valve seat; means for regulating the extent of upward movement of said auxiliary air valve; a fuel supply nozzle located, within said primary air inlet passage; and a fuel supply valve carried by said auxiliary air valve and adapted to control the flow of fuel through said fuel supply nozzle.

15. In a carburetor of the class described, a suitable casing having a mixing chamber, a vertically extending air inlet passage leading into said mixing chamber, a series of auxiliary air inlet ports located adjacent the upper end of said primary air inlet passage and through which air may flow into said mixing chamber, and a permanently open and uncontrolled outlet passage leading from said mixing chamber; an annular valve seat surrounding the upper end of said primaryair inlet passage; avertical-ly movable suction operated annular air valve located within said casing and having an annular seating surface adapted to co-operate with said valve seat; an adjustable Stop member adapted to regulate the extent of upward movement of said auxiliary air valve; a fuel supply nozzle located within said primary air inlet passage; and a fuel valve carried by said auxiliary air valve and adapted to control the flow of fuel through said fuel supply nozzle.

i 16. In a carburetor of the class described, a suitablecasing having a mixing chamber, a vertically extending permanently open and uncontrolled primary air inlet passage leading into said mixing chamber, a series of auxiliary air inlet ports located adj acent .valve and adapted to control the the upper end of said primary air inlet passage and through which air may flow into said mixing chamber. and a permanently open and imcontrolled outlet passage leading from `said mixing chamber; van annular valve scat `surromiding the upper end of said primary air inlet passage: a vertically movable annular air valve located within said ,casing and having an annular seating surface adapted to co-operate with said valve seat. the inner surface of said casing having concentric portions of different diameters, and the periphery of said air valve having also concentric portions of different dia-meters ada ptcd to move in contact with the concentric portions of said casing, whereby an air chamber is provided between said valve and casing: a fuel supply nozzle located within said primary air inlet passage; and a fuel valve carried by said auxiliary air valve and adapted to control the flow of fuel through .said fuel supply nozzle.

17. ln av carburetor of the class described, a suitable casing having a mixing'chamber, a vertically extending permanently open and uncontrolled primary air inlet passageleading into said mixing chamber, a series of auxiliary air inlet ports located adjacent the upper end of said primary air inlet passage -and through which air may flowinto said mixing chamber. and a permanently-open and uncontrolled outlet passage leading from said mixing chamber; an annular valve seat surroun ling the upper end of said primary air inlet passage; a vertically movable annular air valve located within said casing and having an annular Seating surface adapted to co-operate with said valve seat, the inner surface of said casing having concentric portions of different diameters, and the periphery of said air valve having also concentric portions of different diameters adapted to move in contact with the concentric portions of said casing. whereby an air chamber is provided between said valve and casing: means for regulating the extent ot upward movement of said auxiliary air valve: a fuel supply nozzle located Within said primary air inlet passage: and a fuel supply valve carried by said auxiliary air flow of fuel through said fuel supply nozzle.

19. ln a carburetor of the class described, a suitable casing having a mixingchamber. a vertically extending permanently open and uncontrolled primary air inlet passage leading into said mixing chamber, a seriesV of auxiliary air inlet ports located adjacent the upper end of said primary air inlet passage and through which air may flow into said mixing chamber. and a permanently open and uncontrolled outlet passage leading "om said mixing chamber; an annular valve seat surrounding the upper end of said primary air inlet passage: a vertically movable air valve located within said casing and having an annular seating surface adapted to co-opelate with said valve seat, the inner surface of said casing having concentric portions of different diameters, and the periphery of said air valve having also concentric portions of different diameters adapted to move in contact with the :concentric portion of said casing, whereby an air chamber is provided between saidlvalve and casing; means vfor regulating the action of said air chamber; means for regulating the extent of upward movement of said auxiliary air valve; a f uel supply nozzle located within said air inlet passage;and a fuel valve carried by said auxiliary air valve and adapted to control the flow of fuel through said fuel supply nozzle.

19. ln a carburetor of the class described, a suitable casing having a mixing chamber, a vertically extending air inlet passage leading into said mixing cham-ber, a series-'of auxiliary air inlet ports locatedadjacent thev upper end of said primary air inlet passage and through which lair may flow into said mixing chamber, and a permanently open and uncontrolled outlet passage leading from said mixing chamber; an annular valve seat su'rroundingthe upper end of said primary air inlet passage; and a vertically movable suction operated annular air valve located Within said casing and having an annular seating surface adapted to cooperate with said valve seat.

20. In a carburetor of the class described, a suitable casing having a mixing chamber', a vertically extending permanently open and uncontrolled primary air inlet passage leading into said mixing chambexga series of auxiliaryl air inlet ports located adj acent the upper end of said primary air inlet passage and 'through which air may flow into said mixing chamber, and a permanently open and uncontrolled outlet passage leading from said mixing chamber; an annular valve seat surrounding the upper end of said primary air inlet passage; a vertically movable annular air valve located within said casing and having an annular seating surface adapted to co-operate with said valve seat,

the inner surface ofsaid casing having concentric portions of different diameters, and the periphery ofl said airv valve having also concentric portions 'of different diameters adapted to move in contact with the concentric portions of said casing, whereby', an air chamber is provided between said valve and casing; and means for regulating the extent of upward movement'of said auxiliary air valve.

21. In a carburetor of the class described, a suitable casing having a mixing chamber, a vertically extending permanently open and unconti Jlled primary air inlet passage leading into said mixing chamber, a. series of auxiliary air inlet ports located adjacent the upper end of said primary air inlet passage,

and through which air may flow into said mixing chamber, and a permanently open and uncontrolled outlet passage leading from said mixing chamber; an annular valve seat surrounding the upper end of said primary air inlet passage; a vertically movable air valve located within said casing and having an annular seating surface adapted to co-operate with said valve seat, the inner surface of said casing having concentric portions of different diameters, and the periphery of said air valve having also concentric portions of different diameters adapted tomove in contact with the concentric portion of said casing, whereby an air chamber is provided between said Valve and casing; means for regulating the action v,of said air chamber; and means for regulat-ing the extent of upward movement' of said auxiliary air valve.

22. In a carburetor of the class described, a suitable casing having an air chamber open at one side, and a heating chamber for heating said airchamber; a mixing chamber; a primary air inlet passage leading from saidair chamber and discharging into said mixing chamber; an auxiliary air inlet passage leading into said mixing chamber; a cover for closing the open side of and having an opening leading into said air chamber; and a fuel supply nozzle carried by said lcover and through which fuel is supplied to said primary air inlet passage.'

23. In a carburetor of the class described; a suitable casing having an air chamber open at one side, and a heating chamber for heating said air chamber; a mixing chamber; a primary air inlet passage leading from said air chamber and discharging into said mixing chamber; an auxiliary air inlet passage leading into said mixing chamber; a cover for closing the open side of and having an opening leading into said air chamber; a fuel supply nozzle carried by said cover and through which fuel is supplied to said primary air inlet passage, a tubular heating member included in said primary air inlet passage; and means for heating said heating member.

24. In a carburetor of the class described, a suitable casing having a transverse partition; an air chamber having a top wall spaced apart from said partition; a heating chamber for heating sald air chamber and which heating chamber includes the space between said partition and top wall: an air inlet passage leading from said air chamber and extending across the space between said top wall and partition and discharging into said mixing chamber; a fuel supply nozzle through which fuel is supplied to said air inlet passage; and an outlet passage leading from said mixing chamber.

25. In a carburetor of the class described, a suitable casing having a transverse partition; an air chamber having a 'top wall'- spaced apart from said partition; a heating chamber for heating said air chamber and which heating chamber includes the space between said partition and to wall; and a primary air inlet passage leading from said air chamber and extending across the space between said top Wall and partition and discharging into said mixing chamber; an auxiliary air inlet passage leading into said mixing chamber; a fuel supply nozzle through which fuel is supplied to said air inlet passage ;fand an outlet passage leading from said mixing chamber.

26'. In a carburetor of the class described, a suitable casing having a transverse partition; an air chamber open at its bottom and having a top wall spaced apart from said partition; a heating chamber for heating said air chamber and which heating chamber includes the space between said partition and top wall; an air inlet passage leading from saidl air chamber and extending across the space between said top wall and partition and discharging into said mixing chamber; a coverfor closing the open bottom of and having an opening leading into said air chamber; a fuel supplynozzle through which fuel is supplied to said air inlet passage; vand an outlet passage leading from said mixing chamber.

27. In a carburetor of the class described, a suitable casing having a transverse partition provided with an opening; an air chamber having a top wall spaced apart from said partition and having also an opening; a heating chamber for .heating said air chamber and which heating chamber includes the space between said partition and V discharging into said mixing chamber; a f

tubular heating member includedin said air inlet passage and extending across the space between said top wall and partition and the ends of which lie within the openings aforesaid in said elements; a' fuel supply nozzle through which fuel is supplied to said air inlet passage; and an outlet passage leading from said mixing chamber.

28. In a carburetor of the class described, a suitable casing having a transverse partition provided with an opening; an air chamber having a top wall spaced apart from said partition and having also an opening; a heating chamber for heating said air chamber and which heating chamber includes the space between said partition and topwall; a mixing chamber; a primary air inlet passage leading from said air chamber and discharging into said mixing chamber; an auxiliary air inlet passage leading into said mixing chamber; a tubular heating member included in 'said primary air inlet passage and extending across the space'betweensaid top Wall and partition and the ends of which lie Within the openings aforesaid in said elements; a fuel supply nozzle through which fuel is supplied to said primary air inlet passage; and an outlet passage leading from said mixing chamber.

29. In a carburetor of the class described, a suitable casing having a transverse partition provided with an opening; an air chamber open at its bottom and having a top wall spaced apart from said partition and having also an opening; a heating chamber for heating said air chamber and which heating chamber includes the spacne between said partition and top wall; a mixing chamber; a primary air inlet passage leading from said air chamber and discharging into said mixing chamber; an -auxiliary air inlet passage leading into said mixing chamber; a tubular heating member included in said primary air inlet passage and extending across the space between said top wall and partition, and the ends of which lie within the openings aforesaid in said elements; a cover for closing the open bottom of and having an opening leading into said air chamber; a fuel supply nozzle carried by said cover and through which fuel is supplied to said primary air inlet passage; and an outlet passage leading from said mixing chamber.

30. In a carburetor of the class described,

a suitable casing having a mixing chamber, an air chamber located below said mixing chamber and open at its bottom, a vertically extending primary air inlet passage extending from said air chamber to said mixing chamber, anv auxiliary air inlet passage lead ing into said mixing cham-ber, and an outlet passage leading from said mixing chamber; an air valve adapted to control the flow through said auxiliary air inlet passage; a

cover for closing the lower end of and having an opening leading into said air chamber; a vertically adjustable fuel nozzle carried by said cover; and a Afuel valve connected with and operated by said air Valve and adapted to control the flow ofy fuel through said fuel supply nozzle.

31. In a carburetor of the class described, a suitable casing having a mixing chamber, an air chamber open at one side, an air inlet passage extending from said air chamber to said mixing chamber, and an outlet passage leading from said mixing chamber; a cover for closing the open side of and having an opening leading into said air chamber; an interiorly threaded supporting member carried by said cover; a tubular member carried by said supporting member and extending into said air chamber; a fuel supply nozzle located within said tubular member; a rotary adjusting member operatively connected with said nozzle and in threaded engagement with the interior of said supporting member; and a fuel supply conduit in communication with the yinterior of said supporting member.

In testimony whereof, we have signed our names to this specification this 19th day of July, 1916.

JHN J.' HAIVXHURST, JR. EDWARD F. NICOLAI.