US1464333A

US1464333A - Carburetor

Info

Publication number: US1464333A
Authority: US
Publication date: 1923-08-07
Anticipated expiration: 1940-08-07

Description

Alg. 7, 1923. 1464'333 W. P. PEMBROKE CARBURETOR Filed May 22, 1917 I5 Sheets-Sheet 2 Aug. 7, 1923. 1,464,333 vw. P. PEMBROKE CARBURETOR Filed May 22, 1917 3 Sheets-Sheet 3 1F iig Q70 Figox 32 27C Hrmvmlwm 23C I All) Patented A110'. 7, 1923.

WINFIELD P. PEIIBROKE, OF ROCHESTER, NEW YORK.

CARBURETOR.

Application filed May 22,

T 0 all who/1L t l17mg/ concer/z Bc it known that 1, lYiNrinLn l). Frm'- nnoiin, a citizen ol the United States, and resident of Boch-ester, in the county o t' Mouroe and State otl New York, have invented certain new and use'lul improvements in Carburetors, of which the tollowing is a specilication.

rl`he present invention relates to carburetors.

To produce a mixture for internal combustion engines it has been the most general practice to employ a Venturi tube into the orifice ot which a nozzle, supplying a hydro carbon is arranged in such a way that the low speeds oit' the motor and increased speeds up to a certain limit can be talzen care ot, but high speeds are unattainable owing to the tact that a nozzle which will work properly in a Venturi tube vfior low speeds will not give suliicient liquid fuel tor extremeiy high speeds, nor will the air opening through the Venturi tube supply sutficient air 'for such high speeds. this air opening being materially smaller in area than the outlet of the mixing chamber into which the liquid fuel and the air are discharged. To obtain a larger volun'ie oi" gaseous fuel for high speed motors, an extra volume o'l hydrocarbon has been obtained by means ot one or more secondary iets and one or more auxiliary air supply passageways. It isalsoeommon toincrease the range ot the single jet carburetor by providing an auxiliary air supply passage. This auxiliary air supply passage, whether in a multiple jet carburetor or in a single jetcarburetor, has been controlled by a metering or measuring device which is operated either through the pressure ot the outside air or mechanically by the operation ot the throttle. '.lhesc measuring or metering devices have to some extent enabled the obtaining of higher speeds but. at certain limits, they have be come faulty, making the obtaining o'tstill higher speeds impossible due to their 'laib ure to supply a gaseous t'uel which will correspond to the demand ot the motor.

It is an object ot' this invention to provide a carburetor with an air supply passage which is equal to any demands ol' the motor, having throughout the length thereof an area which is substantially equal to the area ot' the outlet ot the passage, provision being made in said air supply passage whereby,

1917. Serial No. 170,183.

with increased demands of the motor, friction will be produced on the air passing through the air supply passage to create about the luel supply a vacuum which will be proportional to the motor demands, so that an increased amount ot fuel will be drawn into the mixing chamber without choking the air supply passage by movable `valves or the like during the etl'ectiveness of such friction producing means.

T o these and other ends the invention consists ol certain parts andi combinations of parts all ol which will be hereinafter described, the novel features being pointed out in the appended claims.

lu the drawings 2- Fig. l is a sectional view through the mixing chamber and the fuel and air supply passage ot a carburetor constructed in acc `lrdance with this invention;

Fig. 2 is a sectional view similar to Fig. l, with the vfuel reservoir removed showing another embodiment in which the air supply passage is deliued by a number of separate rings and disks;

Figs. 8 and il are perspective views, respectively, oiE one o'lI the rings and one of the disks employed in the embodiment shown in Fig. 2;

Fig. 5 is a sectional `view through the air and fuel supply and the mixing chamber ol the carburetor, the improvement being embodied in the auxiliary air supply passage instead ot the main airsupply pas sage, as in the embodiment shown in Figs. l and Q;

Fig. G is a lragmentary section of the embodiment shown in Fig. 5, showing the throttle valve in open position and the auxiliary air valve open;

Fig. 7 is a sectional view ot another embodiment. ot the invention in which the invention is embodied in an auxiliary air supply passage,y and other 'features are combined with the improvement to lurther increase the ellieicucy ot the carburetor.

Fig. S is a fragmentary view of the embodiment shown in Fig. 7, showing the throttle valve and the auxiliary air supply valve open;

Fig. 9 is a section on the line 9&9, Fig. 7 andI F ig. 10 is a section on the line lO-l0, Fig` 7.

Referring more particularly to the draW- ings, l indicates the fuel supply receptacle which, by way ol a passage 2, connects with a luel nozzle 3 which extends vertically and has lateral discharge ports e, the nozzle being controlled by a needle valve 5 ot' any desired construction. Surrounding the nozzle 3 is a casing 6 provided with a flange l" adapting it Ylior attachment to the manifold oil an engine, and having an outlet 8 in which the throttle valve 9 is mounted. ,ilit the lower portion ot the casing is a lateral extension l0 serving as an air inlet, and controlled by a valve l1 Which is preferably under the control of the operator of the inachine.V rlhe central or body portion of the c: sing 6 is preferably enlarged with respect to the outlet and inlet portions, and is provided with aplurality oli' internal annular battles or flanges l2. Extending between these Vba'l'lles or flanges l2 are a number of annular battles or flanges i3 arranged on the fuel supply nozzle :3. The flanges l2 and 18 provide a circuitous passage tor the air which discharges with the tuel into the vacuum or mixing chamber lll. The areal of this passage is such that any section thereol, talren transversely of the `l'loiv of the air, will have an area substantially equal to the cross-sectional area of the outlet oi the passage. By this arrangement the air in passing through the air supply passage meets with a resistance or friction due to the number oit return bends or turns it is required to malte, and this resistance increases propoi tionately with an increased demand ot' the engine, so that the higher the demand in the engine, the greater will be the vacuum or suction about the fuel nozzle. the @greater i Will be the amount of fuel drawn troni the fuel discharging openings 41T, and the greater will be the amount of air drawn through the air supply7 and this While maintaining the air `supply opening constant and without the manipulation or operation oli any movable valves for varying the vacuum or suction in the mixing` chamber with an increased dcmand by the motor.

In the embodiment shown in Figs. 2, 3 and #l the discharge nozzle 3 has its discharge openingi la at its upper end discharging .into the mixing chamber la, The casing which surrounds the nozzle is liorined ot a number ol superimposed rings 6 With internal annular bailles or Hangt-s 12u. The throttle 9 is mounted in 'the outlet member 8 which by bolts Sa connects with the inlet section l0a constructed similar to the inlet ol? Fig. l. These bolts tend to hold the outlet section tothe inlet section and secure the rings 6a between them. lt is apparent that the rings as Well as the outlet and inlet sections. may be provided with suitable joints which will provide a sul l' tight casing. The annular b2 Yis or llangres 13 in the formel disks project from the annular supply nozzle 3, and have sleeves le depending therefrom and surrounding the nozzle 3a to act as spacers to hold the flanges or disks 13 separated. This construction, lilre that illustrated in Fig. l. causes the air to pass in a circuitous path and to be resisted to such an extent that a 'vacuum will be created about the fuel nozzle proportional to the demand of the niotor, so that a greater supply olf 'luel is obtained with an increased demand Without reducing the cross-sectional area ot the HOW of air substantially below the cross-sectional area oi the outlet 8 from the mixing chamber.

rlhe embodiments of the invention shown in Figs. l to 4 are designed for use with motors which Work under substantially constant loads and do not vary substantially belen7 25% or the normal working speeds, say, a motor having a speed of 2000 revolutions which Would operate as lon' as 500. Beloiv the minimum speed, the air passing through the air passage would be substantially free from friction, and it is for this reason that the valve l1 is introduced in the air passage in order that a vacuum may be created in the carburetor for starting the motor.

ln the embodiment or the invention shown in Figs. 5 and 6, the fuel receptacle 'lb connects by a passage 2 With a fuel nozzle 3b; the latter having the outlet or discharge Lib at its upper end, and being controlled by a needle valve 5b. Surrounding the fuel supply nozzle is a main air supply passage 1G which discharges With the nozzle 3b into the mixing chamber 14h, the Wall of the main air supply passage being extended above the nozzle and flaring as at l?. From the mixing chamber an outlet Si leads controlled by a throttle valve 9b. Also delivering into the mixing chamber lll-l is an auxiliary air supply passage which is termed by a casing G" surrounding the wall l which provides the main air supply passage i6, the main air supply passage and-the auxiliary air supply passage both opening to a chamber 19 at the bottom of the carbure tor, said. chamber opening to the atmosphere by Way oi5 the surroundingr opening 20. ln this instance, 'this surrounding opening` may have its area. increased or decreased, and to this end the loiver Wall 2l ol the chamber 19 is ol cup formation, and adjustable to- Ward and lrom the casing 6b on a stem 22 which projects from parts carried by the casing Gl. lt Will be noted that a circuitons path is formed for the air passing through the auxiliary air supply passage. this path, in this instance, being provided by internal annular flanges or battles l?, and annular projections 13 on the Wall i8 Which Jforms the main air supply passage. ltassage oil air through the auxiliary air supply "passage may be controlled by a valve 23, which oper` lill) ates within the mixing chamber 14, and has beveled face 24; cooperating with a beveled tace 25 on thc projection 18.

The purpose of 'producing this circuitous passage is to create a vacuum in the auxiliary air supply passage that will be proportional to the demand of the motor, so that after the main fuel supply nozzle has reached its maximum etliciency, an auxiliary fuel supply will be brought into use. said auxiliary fuel supply,` in this instance, being formed by a passageway Q6 having its discharge 27 in the auxiliary air supply above the uppermost battle or projection 1Q, this fuel supply being` controlled preferably by a rotary valve 2S which, by a link 29, may be connected to the throttle valve 9b, so that the closing ot' the throttle valve will close oil' the auxiliary fuel supply and the opening ot the valve to a certain position will open the supply.

lVhen the motor is running slowly, it will draw air through the main air supply passage 16, past the discharge opening 17, and into the mixing chamber 14h. During such slow speed of the motor, the valve 23 remains closed, due to the fact that suthcient air can pass through the main air supply passage, and also to the fact that the valve has sutlicient weight to maintain its seat un der the above condition. As the speed of the motor further increases, the auxiliary air valve Q3 will open, permitting the passage of air through the auxiliary air supply passage in order to supply sutlicient air for the nozzle 3b. The auxiliary air valve 23 will open to its full extent without imposing any material resistance to the passage of air through the auxiliary air supply passage, and no fuel Will be drawn from the auxiliary fuel supply nozzle 27. lWith a still further increase in the demand of the motor, the mixture would become lean. and to prevent this the auxiliary Yfuel supply 2T is employed for the-purpose of supplying additional liquid fuel. No material amount of liquid fuel passes from this auxiliary fuel supply until the valve 23 has reached its maximum opening movement. after which the increased demand of the motor produces a vacuum in the auxiliary fuel supply passage, due to the arrangement oil the bullies 12L and 13 which create a friction on the air,` producing` a vacuum in the auxiliary air supply passage which is proportional to the demand of the motor, and thus increasing the supply of liquid fuel Jfrom the auxiliary fuel supply 27. Any section of the auxiliary 'air supply passage taken transversely of the flow of the air has an area substantially equal to the cross sectional area of the outlet ofthe passage, as is true also ot the main air supply passage shown in Fig. 1,l

so that a maximum amount of air can pass through the auxiliary air passage. It will thus be seen that in Fig. 5 substantially two carburetors are embodied in one structure. the main carburetor which acts alone during the slow speeds of the motor utilizing the air passageway of the other carburetor as an auxiliary air supply passage up tothe point at which the auxiliary air supply valve opens to the limit of its movement. without bringing into operation the liquid fuel supply of the second carburetor. llllien the auxiliary air supply valve has opened to the limit of its movement, then a vacuum is created in the air supply ot' such second carburetor, or the auxiliary air supply of the main carburetor, which is proportional to the de` iii-and of the motor, and thus acts upon the liquid fuel supply of the second carburetor to draw from the latter an amount of fuel corresponding to the demand ot the motor.

In the embodiment shown in Figs. 7 to 10 1 indicates the fuel receptacle from which leads the main ituel supply nozzle 3C controlled by the needle valve 5c and discharging into the mixing chamber ille, the latter having the outlet Sc controlled by the throttle valve 9, and also having an inlet 10c controlled by the valve 11C. The mixing chamber 14C is separated from thel inlet 10c by a partition 230 of cup formation having a central opening 31 lthrough which the fuel nozzle 3 projects, the discharge lo of the nozzle being slightly above the bottoni ot the cup portion and being spaced from the side walls of the opening 31 to provide an opening for the passage oit' air from the main air supply passage 10C. This partition 30 has its edges resting in seats formed in an elbow in which the fuel nozzle 3 is arranged, said elbow being detaehably secured tothe casing member in which the mixing chamber 11i-c is formed. By this arrangement, the cupped partition may be readily removed and another partition introduced having the air opening of a ditl'erent size.

Above the nozzle 3, the mixing chamber illu is provided with an auxiliary air supply passage which, in this instance, is controlled by a valve Q3, this valve having a stem 32 projecting from one face thereotI and secured to a piston 33 which operates within a cylinder 3st. The valve is held in a closed position preferably by :i helical spring 35 mounted within 'the cylinder del. The opening of the valve is eii'ected preferably by the sum tion produced within the mixing chamber 14C. this being effected, in this insta1'1ce,-by a passageway 36 leading from the mixing chamber on the side ot the throttle valve 9 nearest the liquid fuel supply and connecting with the cylinder 34, so that the suction acts on the piston 33 aswell as the valve 23C to open the valve 23C. lVithin this passageway 36 a check valve 37 may be arranged` this valve opening` under the action of the suction ol the engine to permit said suction to act on the piston lt also closes upon the reduction ot the suction due to the pulsation ot the motor, so that the vacuum in the cylinder 34]; is maintained during` the successive pulsations in order to prevent the valve 23C closing under the action ot the springl This action prevents an increase ot' 'vacuum in the mining` chamber on every pulsation due to the closingv ot the valve on each pulsation and to the necessity ot opening the valve thereafter.

llntil the yalye 22 C has opened to the limit oft its movement, the air passes through the auxiliary air supply puissant-P. without material resistance, to supply additional air ttor the liquid tuel trom the nozzle Ll". ritter a time, it no additional iluel supply were provided` the =gaseous tuel would become lean, and to prevent this, an auxiliary fuel supply 2T" is introduced'into the auxiliary air supply passage. Such auxiliary tuel supply docs not become eiliective until a vacuum ot suiiicient strength has been created in the auxiliary air supply passage. rthis vacuum, in this instance, is obtained by causing the air to pass in a circuitous path, or to malte one or more return bends in order to produce a Yfriction on the air so that the vacuum in the auxiliary air supply passage will be proportional to the demand ot the motor. ln this instance, the air supply passage is enlarged at B9, and the bailiie plate Ll0 is arranged in the enlarged portion, so that the air is caused to pass about the plate and to malte a return bend. Fron'i this plate a stem Lll projects to support a cup-shaped member il which is adjustable on the stem and surrounds the end ot the tube in which the baille Jl-,O is arranged, to provide a passageway t3 between the outewalls ot the tube and the inner walls ot the cup-shaped men'iber, the extreme edge ot the cup-shaped member lying' in proximity to the enlarged portion 29, so that a passageway is formed between th e enlarged portion and the edge ol' the cup-shaped member, causing; the air toy malte a turn at this point.

ln all embodiments oit the invention there has been provided an air supply passage in which is maintained a suction or vacuum that is proportional to the demand oit the motor. The cross sectional area ot the opening throughout the air supply passa'ureway is substantially equal to the area oi' the outlet Ytrom the air supply passageway, and during theeticctiveness ot the vacuum producing` means o' the air supply 'iassageway .is not controlled by any movable part such as valves. Bythis arrangement it is possible to obtain the desired amount ot air while at the same time increasing the vacuum or suction within the passageway to such an extent that an increased amount ot fuel will be obtained. ',lhese results are secured by causingthe air te pass through. a circuitous inea-,ses

path under the suction ot the motor, thus tendiner to hold back the air without restricting; the size oit the passageway. Preterably this result is obtained by making the air travel through a number ot return bends, and preterably about battles arranged within the air inlet without restricting the area ot the passageway.

A carburetor constructed in accordance with this invention is adapted ttor motors of the largest type and the `great/est speed where a great amount ot power is to be deyeloped and where a large amount ot flex ibility is desired, that is, where the engine is to be run at a very low speed and to be uniformly run up to the extreme or highest speed and to develop the highest power ai the dill'erent speeds.

lllhat l claim as my invention and desire to seciire by Lettere Patent is:

l. ln a carburetor, a fuel sumily and an air supply pass Aaeway haviup,`

.ed means therein, inoperative at sta-rima` or on slow speeds, but op-,ative on higgh speeds tor maintaining,- a vacuum about the 'fuel supply to draw an amount ot fuel coi responding;h to the demand of the motor in runuinn' at high speeds, the opeiiiing tl'iroughv out said air supply passage rar having a cr setional `area substantially equal to the area ot the discharge from the passage way, while such means in the air supply passage is etlertive, and means associated I i the carlniretor tor eti'ectinuj the `tunetioninp; ol the carburetor an starting? au d tor slow speeds.

2. ln a carburetor., a tuel supply and an air supply passageway tor said ilfuel supply l aviup; means. inoperative at starting or on slow speeds., but operative on hinh speeds tor causing' the air to make a number ot return bends, the area throupf'l'iout the air supply passageway beineY substantially equal to the area oi the outlet ot said passageway, while such means is etl'ective, to produce a resistance to the air to cause an an'iount ot tuel to be :ted troni the 'fuel supply correspomldnp,- to the demand ot the motor in running at high speeds, and means associated with the carlniretor 'tor etli'ectinul the tunctioning` olithe carburetor :tor siarting and tor slow speeds.

2. ln a carburetor, a tuel supply and an air suliply passageway tor said liuel supply having' battling' means therein, inoperative on startiiig' or slow speeds, but operative on high speeds the passageway about Vthe builtin@v means having a cross sectional area subs ,antially equal'in area to the outlet 'from the passageway, while such battling means is eitective, to produce a resistance to the air to cause an amount of fuel to be 'ted trom the fuel supply corresponding to `the demand of the motor at high speeds, and means associated with the carlmretor tor effecting the functioning of the carburetor for starting and for slou7 speeds.

4. In a carburetor, a fuel supply and an air supply passageway for said fuel supply provided With at least one return bend therein inoperative at slow speeds but operative on high speeds to produce a resistance to the air to cause an amount of fuel to be fed to the fuel supply corresponding to the demand of the motor at high speeds and means associated Vwith the carburetor for effecting the functioning of the carburetor for starting and for slowr speeds.

In a carburetor, a mixing chamber, a main fuel supply communicating therewith, a main air supply passage leading to said mixing chamber and having the air passing therethrough acting on said main fuel supply, an auxiliary air supply passage leading to said mixing chamber, a section-controlled valve for said auxiliary air supply passage, an auxiliary fuel supply acted on by the air passing through said auxiliary supply passage, and means provided in the auxiliary air supply passage and effective on the opening of the suction-controlled valve to maintain a vacuum in the auxiliary air supply passage to produce such resistance to the air as to cause an amount of fuel to be fed from the fuel supply corresponding to the demand of the motor, said means being constructed to maintain a cross sectional area throughout the auxiliary air supply passage substantially the same as the outlet from said auxiliary air supply passage.

(i. In a carburetor, a mixing chauiliier, a main fuel supply communicating with said chamber, a main air supply passage having the air passing therethrough acting on said main fuel supply, an auxiliary air supply passage for said chamber, an auxiliary fuel supply acted upon by the air passing through said auxiliary air supply, and an automatic valve for controlling the passage of air through the auxiliary air supply passage, bafliing means in said auxiliary air supply to produce a resistance to the air to cause an amount of :fuel to be fed from the auxiliary fuel supply corresponding to the demand of the motor after the opening of the valve, said baflling means being constructed to maintain a cross sectional area throughout the auxiliary air supply passage substantially equal to the outlet from the auxiliary air supply passage.

7. In a carburetor, a mixingchamber, a main fuel supply communicating with said chamber. a main air supply passage for having the air passing therethrough acting on said main fuel supply, an auxiliary air supply passage, an auxiliary fuel supply acting upon the air passing through said auxiliary air supply passage, an automatic valve controlling the flow of air through said auxiliary air supply passage, means, effective only when the automatic valve is opened, to produce a resistance to the air in the auxiliary air supply passage to cause an amount of fuel to be fed from the auxiliary fuel supply corresponding to the demand of the motor, While maintaining a cross sectional arca throughout the auxiliary air supply passage substantially equal to the outlet from the auxiliary air supply passage, and means for retarding the closing of the auxiliary of the automatic valve.

S. ln a carburetor, a fuel supply, an air supply passage having the air passing therethrough acting on the fuel supply and having fixed means therein, inoperative during the starting or sloiv speeds of the motor and thereafter operative for maintaining a vacuum in the air supply passage to draw an amount of fuel corresponding to the demand of the motor in running, the opening throughout the air supply passage having a cross sectional area substantially equal te the outlet from said passage, and adjustable means for controlling the passage of air through said air supply passage for effecting operation of the carburetor for starting and during low speeds.

9. ln a carburetor. a fuel supply, an air supply passage having air passing there` through acting on said fuel supply and having fixed means therein inoperative during starting and low speeds, the end of said air supply passage being of tubular formation, a cup-shaped 'member fitting over 'the tubular end to provide a space betiveen the inner ivall of the cup-shaped member and the outer Wall of the tubular end, and means for making said means operative on high speeds for maintaining a vacuum in the air supply passage to draw an amount of fuel corresponding to the demand of the motor in running.

l0. In a carburetor, a main fuel supply.y a main air supply, an auxiliary fuel supply, an air supply passage for said auxiliary fuel supply having its Wall enlarged and provided with a tubular intake end beyond said enlargement, a cup-shaped member adjustable toward and from said enlargement over said tubular end to provide a circuitous path for the air for producing friction on the 'air after the motor has reached a certain speed which will maintain a vacuum about the fuel supply to draw an amount of fuel corresponding to the demand of the motor in running at high speeds, and means for rendering such auxiliary air supply pas sage ineffective on starting and slow speeds.

ll. In a carburetor, a fuel supply, an air supply passage having the air passing therethrough acting on the fuel supply and having fixed means therein, inoperative during the starting and low speeds of the motor,

und thereafter operative for maintaining u vacuum iu the passage to draw an amount of fuel corresponding to the demand of the motor n-runnng, the opening throughout the ail supply passage being; substantially equal in @toss sectional Iareau tothe discharge from the uit supply passage, and un adjustable means for controlling the passage of air through said air suppy passage, said means being situated at the intake end of the nir supply passage for the purpose of varying the 'friction in the uil to adapt the carburetor to the motor.

W. P. PEMBRUKE.