US2480853A

US2480853A - Carburetor

Info

Publication number: US2480853A
Application number: US602218A
Authority: US
Inventors: Edmund E Hans
Original assignee: Individual
Current assignee: Individual
Priority date: 1945-06-29
Filing date: 1945-06-29
Publication date: 1949-09-06
Anticipated expiration: 1966-09-06

Description

Sept 6, i949. E. E. .HANS 2,480,853

CARBURETOR v 2 Sheets-Sheet 1 Filed June 29, 1945 n INVENTOR.

fM/-/ams BY v iPatentecl Sept. 6, 1949 UNITED STATES PATENT .OFFICE Edmund E. Hans, Detroit, Mich. d Application June 29, 1945, Serial No. 602,218

Claims. (Cl. 261-18) ing chamber varies proportionately to the amount of suction exerted in the intake mani-fold. However the volume of fuel required for economical loperation does not vlary throughout the entire driving range in exactly this ratio, and it is for 'that reason that such low mileage is obtained when driving at high speeds.

It is an object of this invention to provide Ya :carburetorincluding automatic means actuated .by the suction of the intake manifold for regulating the flow of fuelfrom the float chamber to the mixing chamber so that the flow does not vary in direct proportion tothe suction exerted at all times. This automatic regulation is obtained by movement of a cam whichactuates a valve, and the cam is so Iformed that, as it is turned by a change in the amount of suction exerted, the Valve opening is always such that the proper amount of fuel passes to the mixing chamber for satisfactory and economical operation of the motor; and to this end it is frequently necessary to provide the contact face of the cam with a sequence of steps which are irregularly spaced relative to the cam axis. Moreover by the simple expedient of substituting one cam for 'another the fuel flow can be set over the entire driving range to best suit anyvehicle working under any particular set of driving conditions, such as a heavy truck operating over mountain roads.

Another object of the invention is to provide a carburetor including two float chambers and two similar automatic regulating means for controlling the flow of fuel from one chamber and the flow of alcohol or other `suitable anti-knock liquid from the other, so that the fuel is economically fed to the mixing chamber throughout the entire driving range, and only when the suction exerted in the intake mani-fold drops below a predetermined amount is alcohol added to the fuel in just suflicient proportion to eliminate ping or knock which would otherwise occur under certain oper- 4ating conditions irrespective of the fuel employed if carbon has accumulated in the engine cylinders. It is however understood that while the second float chamber and the automatic means for regulating the ow therefrom may be added to eliminate knock under 'all driving conditions the carburetor is not only. fully operative but gives highly economical operation when only a single fuel oat chamber and one ,automatic regulating means `for -the flow therefrom is employed;

In an internal combustion engine greatest suction is exerted in the intake manifold-which may be up to 27 inches of `vacuum-when the engine is idling. Then there is no tendency :for the engine to knock and nothing would be gained by adding alcohol or other anti-knock liquid to the gasoline, but when the engineis running at 'from '75 to 100 percent of capacityv the suction exerted by the manifold drops to' below 8 inches of vacuum and a knock is liable to result. Consequently it is only when the suction' drops to about 8 inches of vacuum or lless that my automatic means functions to regulate a ow of alcohol to the mixing chamber in just sufficient quantity to prevent a knock developing. Y

A further object of the invention is to provide such a carburetor with a manual adjustment for setting the mechanism by which one of the valves is operated so that the degree of opening of that valve throughout the entire' suction range may be varied to suit the -fuel being employed. When only one float chamber is being utilized the manual adjustment'is employed for initial setting of the automatic regulating means for the flow from that chamber from which in that case fuel passes to the mixing chamber; because the amount of gasoline required depends uponthe grade of fuel used. When two float chambers are provided the manual adjustment is employed to set the degree of opening of the valve through which the alcohol passes for any given degree of suction because with high octane gasoline a knock ldevelops at a lower degree of suction than when a poorer fuel yis used. Consequently while itmay be necessary to begin feeding alcohol, to eliminate knock, when the suction drops 'to say 8 inches of vacuum, with poor gasoline, it may be possible to allow the alcohol valve to remain closed until the suction'in the intake manifolddrops to 6 inches when a better gasoline is being burnt. Y

Another object of the invention is to provide such a carburetor with another manually operable means for adjusting the'automatic regulation so that either'a greater or lesser suction is required to operate the valve or valves. 1 n,

Yet another objectof the inventionis to provide such a carburetor with automatic means for preventing the @air intake valve being fully opened when the alcohol iloatchamber is empty, -because then a fully openedy intake with the engine operating under full `load `Well result in such excessive knock asto. damage ,the engine particularly if a low grade of fuel were being employed.

HaVIlg thus brieystatedsome of the objects and advantages of the invention I will now describe a preferred embodiment thereof wherein two float chambers are provided with the aid of the accompanying drawings, in which:

Figure 1 illustrates a side elevation of the invention, and

Figure 2 is a plan view thereof.

Figure 3 is a section on the line 3-3 of Figure 1.

Figure 4 is a diagrammatic view showing the plunger ata different position in the cylinder.

Figure .5 is e. section-on the line `5--5 of Figure 1.

Figure 6 is a section on the line 6-6 of Figure 2.

Figure 7 shows a slight modification.

Referring to the drawings, I designates the body of a carburetor having float chambers 2 and 3 therein which are provided with inlet passages 4 and 5 and have floats 6 and 1 respectively therein. The flow through each inlet passage 4 and into its chamber; and 3 respectively is controlled 'as shown 'in Figure 6 in .connection with'the chamber 2 b y a .valve 8 operated upon movement o f ,the "oa'tf to vopen or close a zport 9 rin thepassage 4. V Formed also in the body I is a mixing chamberl to which the chambers 2 and 43 are 'connected through passages ,II and `Ha, and 112 and T I2a respectively formed .through 'the said body; V `the Passages I I and I2 are upwardly inclined from'the chambers andthe Vpassages Ilo, .and I 2a .are above the .normal liquid `level in the Chambers. In the passages IIa and IZa valve seats 'I3 aridll4 areproyided which are Vadapted to beclosed by needle valves I5 and I5 which are mounted in alignment fand extend through opposite sides of the body I. .-II and I8 denote springs 'each Secured at one extremity to the'body Ltolllge"the valves I5 and Irespectively toward 'their closed positions.

Integral with thc'body l iis Va-bIacIQet I9 through which a pin .2 0 extends, and .mounted for sliding movementuponjthellatter is `a'membe'r 2.I having a lug 22 progiecltinglaterally Atherefrom. A vhelical Vspring -213is mounted .around .the pin .2 0 `between the 'bracket I9 and the member 221, and formed uponthe outer side .ofv zthe'latter isa bearing lface '24 against which La "camming .element l25 .pivoted atZDa on "the pin 1.0 is .adapted to vbe rturned so 'that by 'a'.iijUSment o f 'the vsaid. element .the .spacing between the bracket VIl! and'lthe member 2I is 'varied "Formed integral with and v,projecting from one side of the bracket vI9iisga'llllZI.

Pivoted on opposite )sides iof the body .I are bellcranks 21 and'zll. Connected jat 'its 'extremities to VVone 1arm `2Ijaan'd 23a of each of the`bellcranks is 'a helical 'spring'fZSwhich Vtends to draw the outer extremitiers'of these arms `toward one another, and threadedfthrough these arms are -screws'tl and 4V3j the "ends of whichbear .against the lugs 22 and 26' respectively. Pivotally supported on the other arms 2.711 and 28h of the bellcranks are dogs -32fand 33respectivelywhich are bent Vintermediately *their length. Mounted for rotation on the"bellcrank arms "21a .and 28a -are cams d4-and35jrespectivelyhaving substantially send-circular V'Contactf'iaces i3141i and 35a

againstwhich'oneextreinity'ofthe dogs

32 and 33 respectively bear. y'The opposite ends vof these dogs are Vseatedn recesses and 31 formed .in the stems 4of Athe V-valves ligand t6 respectively. The cams 34 Iand L35 are' connected by` a link '38 so that when the fcax'n isturned in-a-manner hereinafter ldescribed 1the'-carndlt `-is also rotated a 'similar Haillan-distanceesorthatmovement is imparted -toboth'flthe valves -Ii5 and-|16.

The purpose oi the camming element 25 is to adjust the opening of the valve I5 relative to that of the valve I6. For as the element is turned the member 2| is moved toward or from the bracket I9 thereby causing the bellcrank 21 to turn about its axis and impart movement to the dog 32. Thus this adjustment occurs without imparting an appreciable rotary movement to either of the

cams

34 and 35.

Formed integral with ,the body ,1I is a cylinder 40 having a piston 4I therein from which a rod 42 projects. The outer end of this rod is connected by a connecting link 42a to the cam 35. Mounted for axial movement on a sleeve 4ta integral with the cylinder 40 and through which the rod 42 fextends is an annularly grooved flange 44; and secured on the rod 42 adjacent its outer extremity a flange 45. Extending between the

flanges

44 and 45 around the rod 42 is a coil spring 46 which tends to retain the rod at its maximum `outwfclrdit' projecting position. Mounted in the opposite .end Qf the cylinder .40 isa tubular connectionM which isalso connected Vto .the intake manifold .(not shown) .so that as suction in the latter increases the 1piston 4l is moved .to the `1eit--lFigures .3 and fthereby turning .the cams inland 3,5 in aclockwise direction and reducing .the opening of the valves I5 and I or completely .closing lihe former. Similarly as the suction `of the 'intake maruold decreases the piston 4| .is moved .back toward the right-Figures 3 and 4t-Shy 'theprirlg 4 6 andthe cams are .then IOiLtQd 'in the OPPQSSC idirelQYl to increase 'the opening `df the said yalves.

Integral with 'the cylinder '4.0 r is a prlection S4 on which .a 'lever .6.5 is. pivoted intermediately of its length. Qne extremity of `this lever is biiurcated to engage oppositesides of the groove around -the flange and vits opposite .extremity `has a control rod 66 pivtally ,attached thereto. By movement of the latter 'in the direction of the arrow A .the closing .of tl'ie wahres .I5 and .L6 is retarded vrs o that Emore alcohol .is added ,to the mixture at any given amount `o suction Iexerted by the intake manifold. The rod .4,2 .is threaded from its outer extremity or engagement with the flange-.4 5 So that thespacing between the latter .and the Harige 414 .may be adjusted 'to regulate the tension .of the spring .45.

1Providedin the body I .above .the mixing charn- Vhers i-.0, and in vertical .alignment .therewith is a conventional .air .inlet .passage 50 having a rod "5I extending centrally .across itand lan ordinary butterfly valve 152 ixed 0n the .said IQd to .control the flow of .air through .thepassage Fixed also on the rod LI-.exterfiorly ci `the vpassage 541s an arm 53 having an adjustable stop .6311 projecting therefrom. Mounted .Qn'the .body I. ,is :a

solenoid 154 'having lleads and '5 6 connected thereto; the lead iS .connected 'to a source o f .power (not shown.) `and@the,lead'l toaterrninal platel mounted cnam! .insulated from'thelbgdy I. Also mounted .on "the, `latter is .a terminal 5 8 having a.resilientcontact259im1ectingtherefrom which tends to. maken connection with the terminal plate 51, tand .extending in om the Vt erininal ,58,15 .alead 56.0 .which .is .also 'connected to the source of power. .Formedthrongh the toe ofthe chamher'2 .isLan aperture 2.a through which a pnBA ontheiiloat .extends This ,pini-I so arranged that as lone as there .isaleoholin the Qha-Ibertosjlnport '.tlie'noat 'the .ninl holds the resilient contact 59. 'in 'itsraisedfizosition shown.' butwhen fthe :chamber Ribecomes .emuty andthe 'float Europsto tspofsition "indicated .at

'Bd the contact`59 also drops and makes a con- 'necti'on as indicated at 59a with the terminal plate 51 whereupon the solenoid 54 is energized. When this occurs the plunger 62 is raised to its position 62a to limit the rotary movement of the stop 53 and thus the opening of the butterfly valve The purpose of this arrangement is to limit the maximum amount of air which may enter the passage 50 when the supply of alcohol is exhausted and only gasoline is being fed into the mixing chamber lll, for under such circumstances a full supply of air might result in such a mixture that the motor would knock very badly, and might blow the head gasket or ruin the engine bearings.

Figure 7 shows a slight modification wherein a diaphragm 10 is substituted for the cylinder 40. This diaphragm is mounted between two spaced, apertured flanges 1| and 1'2 formed invtegral with the body of the carburetor. Extending through the flange 1| and secured at one exn tremity to one side of the diaphragm into which it opens is a tubular connection 41a which is also secured to the said flange 1I. The opposite end of this connection 41a is connected to an intake manifold (not shown). Mounted on and projecting from the opposite side of the diaphragm is a rod 42h which is axially movable through the flange 12 so that the length of the diaphragm is controlled and the rod 42b is moved through the flange 12 by suction exerted by the manifold.

As already stated one float chamber and the partsA required for automatically regulating the opening of the valve between the float chamber and the mixing chamber may be dispensed with if it is merely desired to obtain economical operation and the anti-knock feature is not to be taken into consideration. Then the float chamber retained is the one the setting of the valve opening from which may be manually adjusted through movement of the camming element 25 and that float chamber is then used for gasoline. It is of course understood that the movement which automatically regulates the flow from that cham ber is still controlled by the suction in the intake manifold operating through the rod 4,2. In the instance shown this would involve the retention of the float chamber 2 and automatic regulation of the valve I3 operated by the rod E2 through the cam 35 and link 38 or other appropriate means, and the eliminating of the float chamber 3, so that the chamber 2 would then beused for the fuel. However when both float chambers are used the camming element is usually only provided for adjusting the automatic regulating means .for the alcohol supply.

The peripheral contact faces of the cams Sii and 35 are usually not continuous curves but consist of a series of narrow lands the radial distance of each of which from the cam axis varies a few thousandths of an inch from the land next to it, though these variations are not necessarily uniform or even continuous as to direction. I usually make each land of such length that any one will contact the

bellcrank

32 or 33 during the variation in the intake manifold suction which occurs within a speed range of about five miles per hour, though for a five mile per hour speed change at some speeds there is a greater variation in the amount of fuel needed for economical operation than during equal changes between other speeds.

It is also understood that the peripheral form of the two

cams

34 and 35 differs. The peripheral form of the cam 35 is such that just sufficient fuel'passes from'the oatchamber 3 at all speeds for economical operation since the amount of suction exerted by the intake manifold varies with the speed. The irregular peripheral form of the cam 35 is such firstly to retard the opening of the valve l5 until the suction exerted by the intake manifold has dropped to a predetermined amount, after which the opening of the Valve increases just sufficiently to admit enough alcohol to prevent a knock developing. In this way though alcohol is much dearer than gasoline the *increased efficiency obtained reduces the total costof the alcohol and gasoline below what the costV of the fuel would have been had gasoline alone been burnt particularly if relatively high speeds were attained, and also eliminates knock.

After the tank has been lled with gasoline the engine should 4be started and the camming member 25 set. This is because poorer gasoline, if burnt alone, commences to knock when the suction exerted by the intake manifold is higher, say about 8 inches of vacuum, whereas with some high octane fuels a knock does not develop until the suction rexerted has dropped to say 6 inches of vacuum, and of course there is no purpose in Vadding alcohol until this point is reached, after which the amount of Valcohol used is increased by the cam 3d as the amount of suction exerted continues to drop.

When the control rod 66 is moved the amount ofthe opening of both valves l5 and I5, when any given amount of suction is being exerted by the intake manifold, is increased or decreased, and of course the opening of the fuel valve I6 is de'- creased in this manner the initial opening of the alcohol valve l5 is correspondingly retarded; and under certain driving conditions adjustment: of this rod is advantageous.

It is also pointed out that if butane or any similar gasis to be used in place of a liquid fuel that it may be fed in the manner described from one of the so-called ffloat chambers though then the float should rst be removed from the chamber.

In the foregoing one embodiment of the invention has been described and shown, it is howe ever understood that alternations and modifications maybe made thereto provided they fall within the scope of the claims.

What I claim is:

1. A carburetor including a float chamber and a conduit defining an air flow pathway, said float chamber and conduit being connected by a fuel passageway, a valve in said passageway for con# trolling fuel flow therethrough, a bell crank lever pivotallyr aixed to said carburetor, a cam on the lever, an adjusting screw on the free end of one of the arms of said lever for adjusting the angular position of said bell crank lever, a valve actuating lever mounted on the other end of said bell crank lever having one end in engagement with the valve and the opposite end in engagement with the peripheral face of the cam, means responsive to fluctuations of air pressure in said air flow pathway for operating said cam and thus controlling said valve, and an abutment carried by said carburetor for said adjusting screw whereby a slight adjustment of said screw will effect a minute radjustment of the cam and valve actuating lever.

2. A carburetor including a float chamber and a conduit defining an air flow pathway, said float chamber and conduit being connected by a fuel passageway, a valve in said passageway for controlling fuel ow therethrough, a bell crank lever :actuating lever mounted onithezother Aend of .said

hellwcrank vlever .having one `end in engagement with 'the valve land the .opposite end in engagement with the peripheral face .ofthe nam, means 'responsive rto pressure fluctuations in said .air

:flow pathway for operating said cam to .control :said valve, a shiftable labutment carried by the icanburetor to provide .a stop for .said adjusting screw, a xcam engaging saidabutment, spring :means for urging saidabutment into engagement 'with said cam, and yielding spring means :connected :to .said lbell crank lever for holding said v:adjusting screw in .engagement fthe stop abutment.

3. A carburetor 'including a bodyhavingga float chamber, .a conduit defining an .air having one :end open to the atmosphere vand the :opposite vend connected to the intake manifold Aof an internal combustion engine, said :body being proyidedwith a fuel vpassageway extending from ssaid float .chamber to said air pathway, a yalvein said passageway for controlling fuel flow '.tosaid pathway, fan 4arm zrockably mounted .on Ysaid .body havinga lateral .extension adjacent the pivot axis thereof, a cam mounted on said arm, .a .valve .actuating lever .pivoted to said lateral 'extension land arranged with one end in engagement with the 'valve .and the .opposite end in engagement with the peripheral surface of said cam, an -adjustng screw carried by the `free end of .saidl arm iengageable with stop means carried :bysaid body, resilient .means for urging said adjusting screw into vengagement with said -stop meansan'd means responsive to pressure fluctuations in saidgintake manifold for .controlling said cam.

4. A carburetor comprising a body having :a :doat chamber and a conduit defining an air flow pathway, one end of said conduit being open to the 4atmosphere and the .opposite vend '-.being adapted for connection with the intake manifold -of an internal .combustion enginasaidbody being `provided with a fuel now rpassageway extending between the float chamber and :air flow pathway, .a valve in'said fuel flow passageway,l a-'control lever pivotally .affixed Ato said lbody having a lateral extension at one end, a-'cam..on said control lever intermediate the pivot point and free :end thereof, a valve actuating ,lever 'pvotally affixed -to said-extension with one end :in engagement with the valve, and fthe opposite end `engaging 4the peripheral .surface .of :the cam, :an :adjusting -screw mounted on the free end .of the :control lever, a shiftable abutment engaging said screw, means for shifting :said ',abutmentfor quick :actuation Aof said control lever, spring means for .urging said control lever in a direction so that .the adjusting screw willengagesaid abutment and means Yresponsive tocpressure :fluctuations in the intake manifoldxof :said internal combustion-engine for rotating saidcam.

.5. A carburetor comprising a .body having .a pair of float chambers and a conduitdening .an fair flow pathway, one end of said conduit lbeing open to the atmosphere .and fthe opposite end being connected to the .intake manifold fof :an vinternal .combustion engine, .said :body being pro- -vided with fuel passageways extending from each of the float chambers to diametrically yopposite v,sides of .said conduit, control valves extending Vinto said body 'and conduit for .controlling :flow of .fuel :from said float chambers .to said :air pathway, .-a Y.pair of bell crank 'leverstpivotally :connected to said body, a cam pivotally attached to `one arm of each vof said bell crank levers, lyaslve :actuating'levers supported by theotherzbell crank Alever arm and arranged Vone for each of saidvalves with one end of said valve actuatingslever in engagement with its corresponding value vand the `other end in engagement with its controlling cam, means on the free ends of the )bell -.crank Iarms for adjusting the angular position thereof, `yielding means connecting said :free arms of the .bell crank levers for urging the same toward one anotherfadjusting means on the free ,ends vof said 4arms engageable with abutment means supported bysaid body whereby a slight inovementlofsaid adjusting means will effect `a minute adjustment of said cams and valve actuating levers, means connecting said cams for simultaneous operation and means responsive to pressure fluctuations in the intake manifold of said internal combustion engine for controlling one of said cams whereby said cams will move in unison .upon pressureguctuations in said manifold.

EDMUND E. HANS.

REFERENCES CITED The following references lare vof record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,110,482 Collier 1Sept. 115, 19.14 v1,338,104! Shurtleff Apr. 27, 1920 1,676,828 Howard et al. .July 10, 1928 1,854,390 Aseltine Apr. 19, 1932 .2,129,930 Hans Sept. 13, 1938 2,142,979 Hans vdan. 3, 193.9 2,392,565 Anderson et al. Jan. 1-8, 194:2