US1640711A - Carburetor - Google Patents

Description

. 1,640,711 Allg- 30' 1927- J. J. A. MILLER CARBURE T O R Filed May 21. 1926 Patented Aug. 30, 1927.

UNITED STATES PATENT OFFICE.

JOHN J. A. MILLER, or DENVER,v COLORADO.

CARBURETOR.

Application filed May 21, 1926. .Serial No. 110,617. v

l ber and a fuel inlet valve in said chamber,

which is operated in conjunction with the usual throttle valve, whereby the opening or closing movement of the throttle valve ef' fects a simultaneous opening or closing movement of the fuel inlet valve, thusyautomaticaliy regulating the fuel feed with respect to the movement of the throttle valve.

Further, to provide a carburetor of this character, in which the mixing chamber is 'provided with a screened outlet opening, an adjustable element in the nature of a wick being arranged to extend up from the bottom of the mixing chamber and partially cover said'screened opening, said wick be ing adapted to absorb fuel admitted to the mixing chamberl and which is carried to the highest point of the .wich by ,capillary attraction, whereby air l drawn through the carburetor combines with the fuel in the wich, thus forming a vaporized mixture, the raw fuel being thus prevented from passing to the engine cylinders. i l

Furtheig'to provide a carburetor -having air inlet valves which are adapted to. beoperated by the usual throttle valve lever, whereby, 'when the throttle valve is wide open, one of said'valves is opened tocadmit additional air to the intake pipe, and when the throttle valve is closed, as in coasting, the other valve is opened, thereby admitting air to the cylinders, which serves, under compression, to retard the action of the 'en-- gine, andslow down the car.

These and other objects to be hereinafter set forth are accomplished by the device illustrated in the accompanying drawings in Fig. 1 is atop view of the improved cai'-,

buretor.

Fig. 2 a view of the inlet end thereof. Fig; 3 is a vertical longitudinal sectional view of the same.

Fi. t is a transverse sectional view on the Referring to the accompanying drawings:` v

The numeral 1 designates the air inlet 'chamber of the improved Carburetor; 2 the mixing chamber thereof, and 3 the outlet chamber.v 'The walls of the inlet and outlet chambers are preferably cylindrical V,in

form while thewallsiof the mixing chamber are flat andthe bottom of this chamber extendsdown below thevother chambers, as shown in Figures 2 and 3.

The. top thereof is closed by aL cap 4 havi in'ggde'pending ribs 5 which lie within the upper endof the chamber and Vcenter the cap upon the top of thev chamber, and the -l cap is held in place by a screw 6 which passes throughholes in the side walls of the cham ber andthrough apertured depending ears 'i' on the cap. VThe end walls ofthe mixing chamber are provided withy air inlet and outlet holes'S andl 9 respectively, which are preferably ofr less diameter than the air inlet and outlet chambers .and lthe highest points lof these holes coincide with the highest points of inlet and outletchambers, as will appear'by reference to Figures 2 and 3. The bottom of the mixing chamber is formed with a raised portion or step 10, which extends the' fullv width of the chamber and v half the .length thereof and an` inlet aperturer f ing adapted to be connected witha fuel supply as in the usual'manner.

A' hole 13 extends down throughthe topV face of the step` and intersects the hole 11,

I and a fuel rinlet, valve V11 ,extends down through a hole 15 in the cap et, and through LIE- the hole 13 and into the inlet aperture 11. This valvel is'in the fo-rmy of a rod or stemV having acollar 16 which restsupon the top of the step 10 and thus limits the downward movement of the valve. The valve has an axial hole 17 which extends from itslower end tol the collar 16 yand a vertical slot 18 extends from the hole 17.0ut through fthe side of the valve and is entirelyclosed by the wall of the hole 13, whenthe collar 16 rests upon the top of the step, and when the valve is raised, as will bey later explained, the .slot 18 is gradually uncovered to admit fuel to the mixing chamber. The lunderside of the collar 16mis slightly. convex and normally rests in corresponding concavity in the top of the step. A constant downward pressure is exerted upon the valve by a coil spring 19 which surrounds the valve andv is interposed between the collar 16 and the under side of the cap 4r 'Ehe-upper; portion of the valve. which extends above the cap 4,

is threaded to receive a thumb nut 2O.v 71th.

" cured anoperating lever 23, which isadapted to be operated from the steering wheel or by a foot lever, in the usual manner. The lever 23 i's formed with an integral extension or arm 24 which terminates in cam member 25' having an arcuate slot 26 whose center is the axis ofthe throttle valve stem'. The upper face of' this cam member is in the form of'v an inclined plane, as shown in Fig. 2,. The upper portion of the fuel valve 14 passes. through the arcuate slot 26 and the thumb nut 2O on the valve isadapted to be engaged by the inclined. face of the cam member either to raise the valve 14, when the lever 23 ismoved in one direction, or to permit the,y valve to descendv under the pressure of the spring 19,` when thel lever ismoved in the opposite direction, as will hereinafter more fully appear. Within the. mixing chamber is placed an L-shaped metalplate 27, thev horizontal portion of which rests upon the bottom ofthe chamber. The

verticalmember of this plate iswformed, with an aperture23` which incloses a line mesh wire screen 29 and thescreened aperture 28 registers with the outlet aperturev 9 vof thev chamber. The aperture 28,. maybe of a diameter touneet the requirements of' the engine as to air supply., The horizontal member o f the plate 27"is bent to form anl oif'set'30, which is on a higher planeY than the remaining portion, andi a slot 31"` isformed, through the bent portion, as clearly shownin Fig.` 6. A piece of absorbent fabric 32, in the nature ofl a wick is. passed through the slot 31, itsY lower end beingbeneath theoffset and this wick extendsgto and' against the vertical'niember of? the plate and partially covers the screenedlopening 2 8 therein. The wick can be adjustedwithrespect to thel screened opening, by a stem- 33.which is mounted at one end: in; one side wall ofthe mixing chamberg its-opposite end portion passing through ahole in the opposite side wall, and lisprovided' with a'V thumb button 34'. The surface of the'stem is serrated, as shown', and bears against the wick, which is thus held between the `stem and-thevertical memberlofthe plate 27, and by turning the stem Jchew-ick can-v be raised or lowered so as to vary they area of the uncovered portion of the screened opening. Before starting the engine, the fuel valve 14 may be lifted to flood the mixing chambergthe4 wick is:` thuS.- Saturated, and when the engine is started the air drawn through the carburetor mixes with the fuel in the wick, which fuel is continuously fed te the highest point off thewick by capillary attraction, and the fuel is thus broken up by contact oftheairwith the wick, and the mixture passes to the cylinders in a highly vaporized condition. The screen 29, prevents t'he wick from beingV drawn throughthe opening 9. lVith this arrangement, the usual chokevalvev is omitted, as the fuel valvecan be raised at willto-flood the mix-- ing chamber.

Air inlet holes 35 are formed in opposite sides of the outletr chamber 3, and these holes are normallyvcovered by valves 36, on theends of lever arms 37, which arepivotf ally mounted on pins extending through ears 37A between whichAt-he arms lie. These arms extend up under the lever 23, and are hori- Zontally disposed for a short distance, their ends terminating in inclined cams 38.

The arms are bent so that their outer portions are'curved to lie in a commonarc whose center is the axis of the valvestem 22, and blade springs 39 aresoldered at one end to thev under side of the lever arms, their opposite ends bearing upon the wall of the chamber 3. These springs exert an upward pressure on the arms, which causes the valves 36-to normally-close the airholes 35. l

A screw extends down throughthe lever 23, i-'n such position that when the lever is turned either to the-right or left, the screw travels in an arc ofthe same radius asfthe curved'I endsof the levers. 371 When the lever23fis moved to openY thethrottle valve to the 'limit of itsV movement, the end of the screw will engage the inclined cam 38 on one. of1A the levers 37, thereby depressing thelever, the valve` 36' ofi which opens the adjoining airhole 35, thusfadmittingair-to the carbu-y retor in addition to-thatV which enters the'- inletf endthereof;

When the lever 23 is movediin the-opposite direction to close the throttle valve, as. in coasting, the end of the screw 40 will engage the inclined cam on the end of the otherV lever arm 37, thereby depressing the. same to cause itsval'veto open the adjoining air holef35, thusadmitting airfto the cylinders, which is compressed by the. pistons,I thus retardingfthe action;.of.the`v engine, and thereby slowing down the car.

yThe screw 40 can be adjusted to give a greater or less valve opening movement to the arms 37', asI may be found, necessary.

The: outletlend; of the carburetor, is. formed with a bolt flange 4l, whereby thecarburetor may-be. secured to aI corresponding flange Von the end of the intakemanifold of the engine.'

In operation, before the engine is started, the valve 14 is lifted to flood the mixing chamber, whereby the wick 32 is saturated and the fuel feeds up to the upper portion thereof, which partially covers the screen 29 in front of the outlet hole 9. The throttle valve 21 is then opened, and the Valve 14 is simultaneously opened by the engagement of the cam 25 with the nut 20 on said valve, thus admitting a regulated supply of fuel to the chamber, through the slot 18 in said valve, and as the inlet and outlet holes 8 and D respectively, are above the level of the slot 18, the air is drawn in a direct line throu h in these holes, and the fuel enteringthrough t e slot 18 replenishes the supply already in the chamber, and which is continuously absorbed by the wick and mingles with the air passing through the chamber, and is thor- -,-oughly mixed therewith, and passes to the intake in a highly vaporized condition, the wick being adjusted to give the best results. By a proper adjustment ofthe nut 20, the` valve 14 can be raised to a greater or less degree, relative to the movement of the throttle valve, thus admitting the desired amount of fuel to the mixingchamber, and the air valves 36 are' opened by the screw 40, at the extreme opening and closing movements of the throttle to admit air to the outlet chamber 3, as above set forth Having described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. The combination with a carburetor havingv a mixing chamber yprovided with air inlet and outlet openings, of a fuel valve and means for operating the same to admit.

fuel to said chamber, said openings being above the level of the fuel inlet, a removable plate in said chamber having anvopening and adapted to register with the outlet opening and a wire screen over the opening in said plate, a fuel absorbing wick adapted to eX- tendpartially over said screened opening, whereby air drawn through said openings mingles with the fuel in said wick to form an explosive mixture, and means for adjusting said wick with respect to the screened,v

the outlet opening, a fuel absorbing Wick' adapted to .extend partially over said screened opening, and means for adjusting the wick andvfor holding the same in con tact with said plate. v

In testimony whereof-I affix mysignatureu JOHN J. ni MILLER.

Images