US1614973A - Carburetor - Google Patents

Description

Jan 18, 1927i y.; F. sHERRlcK CARBURETOR Filed Oct. 27. l1920 and an object of the invention `is to 'had to the Patente-cl Jan. 18, 1927.

EDWARD F. SHERRIGK, OF LOS .ALY.\TG'II1.`IIIES,l CALIFQRNIYLA.

'cemsuanron 'y Application led October 27, 1920. Serial No. `4.19,894.

This invention has to do with a carburetor for-internal combustion engines andthe like, proyide a simple, effective and elicient device of that character.

The various objects and features of the invention will be best and more fully understood from the following detailed description of a typical preferred embodimentl of the invention 'throughout which reference is accompanying drawings, in Which- Fig. 1 is a vertical section through the carburetor; Fi 2 is a. vertical section through the car uretor, -being a view taken as indicated by line 2-2 on Fig. 1; Fig. 3 is a horizontal section of the carburetor be- .1ng a view taken as indicated `by line 3 3 on Fig. 1; and Fig. 4 is anenlargcd detailed section taken as indicated by line on Fig. 2.

- end of the Throu hout the drawings numeral 10 des- Vignat'esrt e body portion .of thecarburetor in connection wlth which isa float chamber 11 and an outlet- 12.- "The'body 10v is preferably `ylindrical in' form'andis disposed so that its lon 'tudinal'axis is'h'orizontal. @ne dy 10 is closed bya'n end plate 13 secured to tbe body 10 by suitable screws 14 while 'the `other end of the body`10 communicates with the 0ut1et12 which is adapt-- ed to be-connected to theintake of the engine or apparatus 'on `which the carburetor is beipgemployed. ,1 ,n

ong each side of-,the body 10 there is a'rranged an air intake manifold 15. lEach of the manifolds 15 is provided with a plurality of parallel vertical: partitions 16,- which divide it into a plurality of ducts or ports '17. It will be noticed from inspection of the drawings that the ports117 are open at their outer ends and that they open at their inner ends'4 directly-into the interior of the body 10. Further it will be noticed, particularl in Fig. 2 of the drawings, that the ports 17 are larger, or of greater capacity, at their outer endsthan they are at their inner ends- Where they communicate or connect into the body 10. It is obvious how a reduction of pressure in the outlet 12, due to the action of the engine on which the carburetor is installed, will cause air to be drawn into the body 10. through the ports 17. The shape of the ports 17 caus'es the air passing through them to increase in velocity as it approaches their inner ends and to reach its highest velocity at ed or restricted .to

` ried'in the float chamber,

the point where issues, into the body 10. This variation in Velocity through the port-s extreme inner ends of the ports 17. Liquidl fuel is maintained in thetubes 20 so that it will be drawn,v from them by the air being drawn through the ports 17 by the engine, thereby causing arnixture of ,liquid fuel and air .to issue into th body 10 from. whence it passes into the outlet 12. The fact that the air at the inner, ends of the ports 17 is at a comparatively low pressure and is moving at a high velocity causes the liquid fuel which is drawnv from the tubes 20 to be very effectively and thoroughly broken up or atomized.

The float chamber 11 which I have illustrated in the drawings Ais airtight and com* prises 'a cup-like member 21 securedv to av `in the cupshaped member 21 by a needle valve 24 arranged to be operated by a suitable iloat mechanism 25. It will be understood,` of course, that the iloat chainber and the parts-in connection therewith may be of any suitable design and construction and that the present invention isv in noway limitthe speciic design or construction herein set forth.`

Tletubes 20 which extend 17 extend downwardly into the liquid carin Fig. 2 of the drawings. Liquid from the into the ports `17 is accompanied by a variation in pressure,l 'at various parts of the ports; the pressure .at 'the outerv portions ofthejports 17, being as clearly shown float chamber stands in the tubes 2() at a level where it will be properly drawn from the `'tubes 20 by the action above described. A'

pipe 30 connects into the outer portion'of j oneof the ports 17 and connects into the up per portion of the ioat chamber. The difference 1n pressure betwcenithe o f the tube 17 liquid the tubes 20. In order that the v outer portion ofthe tube 17 and the inner portion will determine the level of level of liquid in the tubes 20 may be adjusted to be at the desired height an adjusting screw 31 is carried in the outer portion of the port 17 into which the pipe 30 is connected. The screw 31 is adapted to be l adjusted to vary the size of theouter portion of the port 17. In practice the screw 3l may be very easily and conveniently adjusted to cause the liquid to ystand at the proper y'nects into the port.

level in the tube 20. l The pressure in the ioat chamber ,is ordinarily less than atmospheric because of the fact that the air has considerable velocity and is at a reduced pressure at the point 'where the-pipe 30 con- In order to control the'amount of miiiture admitted into the body 10 and to cause the ports 17 to handle a certain volume of air the valve 40 is arranged in the body 10 and is adapted to be actuated or positioned to allow only the proper number of ports 17 to communicate with the interior of the body 10. The valve 40 is. a drum-shaped structure carried on a suitable shaft 41 supported-in bearings 42 and 43. The valve 40 accurately fits the interior of the drum 10 and is formed with two substantially diametrically opposite openings'44. It will be seen from inspection of the drawings that the openings 44 are subst-antially triangular shaped and are arranged so that their long edges extend across and around the valve. TheV lon edges fof the openings are referably s aped as shown in the' drawings.

From inspection of the drawings it will beI readily understood how the valve 40 may be otherA when' the valve is rotated. In accordance with the present invention the valve 40 is automatically operated to open and close the ports 17 so that for any speed of operation there will be 'just a suili'cien't number of ports 17 open to handle the reuired amount of air at a certain velocity. n other words, the invention provides means whereby the ports 17 are opened and closed so that all of the 'ports in-operation" always operate under certain predetermined conditions, that is with respect to velocity and pressure of air, thus causing the carburetor to deliver a uniform mixture at all speeds of operation.. The regulation of the valve 40 is accomplished by connecting the upper end of cylinder 50 with the manifold 12 by means of a duct 51. A plunger 62 is carried in the cylinder 50'and is adapted to be moved in the cylinder by variations of pressure in the cylinder.v A rack 53 is connected to the plunger 52 and is arranged to engage 'ber when one or more ofthe ports 4or that may fall within a gear 54 n1ounted on the shaft 41. The welght of the various parts normally holds the plunger rack, etc. in the osition shown yin Fig. 1 of the drawings. ith this positioning of the mechanism the valve 40 is in position to leave only one port 17 in communication with the interior of the body 10.

IVhen the throttle 'valve-60, which is arranged in theoutlet 12, is opened allowing mixture to be drawn from the'body 10 there 7C ,is a reduction of pressure in the manifold 12l below the valve 60 causing a. corresponding reduction of pressurein the cylinder 50. This allows the atmospheric pressure on the under side of the plunger to move thc vplunger upwardly in the cylinder and thereby -move the rack. The rack meshing with the-gear 54 rotates the shaft 41 and the valve j 40. The valve 40 is rotated by this action in such direction as to open more ports 17 85 and admit a greater amount of mixture into the body 10 to b e supplied to the engine. It will be understood how regulation or positioning ofthe throttle valve will Vary the pressure in the' outlet 12 and thereby vary 90 the position of the plunger 52 inthe clyinder 50. The positioning otf the plunger 52 in the cylinder 50 determines the positioning of l the valve 40 and theamount of airbeing admitted into. the bod 10. By opening and closing the ports '1" with variations in speed of` operation the d'evice is regulated so that substantially a predetermined amount of air fiows through each open port I17. This causes the velocity of air at any given part of an port 17 to be substantially the same at al speeds of.. operation .causing the atomizing action to be substantially uniform in all of the ports 17 and at all speeds of operation. The fact that the atomizing action is substantially uniform vand constant, for all speeds of operation rmits ofthe various parts being "designe and proportionedto operate in the most eieient and effective mannen t, v .In the preferred form of the carburetor checkvalves 61 are provided in the tubes 20 i to prevent atmospheric-pressurebeing comv municated to the interior of the float chamclosed. Therheck valves 61 may be of any desired construction; for instance they may be ball check valves such as is shown in Fig. 4 of the drawings. l

l Having set forth only a preferred embodiment of my invention I do not wish to limit or restrict'myself to any of the specific details hereinabove set forth but wish to re serve to myself any changes or variations that may appear to those skilled in the art the scope of the following( claims.

Having ldescribed a preferred form of my invention, I claim: -1. n a carburetor having a fuel chambeii,

'n ,applied, a plurality a mixing chamber to which suction may be y of fuel jets to carry fuel from the fuel chamber to the mixing chamber, and a valve by means of which the several jets may bel progressivelycut `off from or put into communication-with the mixing chamber; thedco'mbination of a come munication Ato the fuel chamber whereby a vacuum is applied thereto to `maintain there onl a lowered pressure slightly above the lowered pressure applied to the jets when in communication with the mixing chamber, and checks in the jets to prevent flow offair under atmospheric pressure through them to the fuel chamber. l .I

2. In a carburetor havin a fuelchamber, a mixing chamber to whic suction may be applied, said chamber having a plurality 'of air inlet openings, a valve by means ofwhich the several air inlet openings may be progressively cut off from or put into communication with the mixing chamber, a fuel jet leading from the fuel chamber to each of said openings and adapted to be subjected to the vacuum in the mixing chamber when the openings are put `into communication therewith; the" combination of a vacuum connection between the fuel chamber and the one of said openings that is first put into communication with the mixing chamber to put a lowered pressure on the fuel chamber somewhat above the. lowered pressure applied to the jet at that opening, and

ing f from' which checks :in` the vj'ets to prevent How ofair when the openings'are put into communication therewith, the combination of va vacuum connection between the fuel chamber4 and ,the one of said openings that is first put into communication with the mixing chamber to put -arlowered pressureon the fuel chamber somewhat above the'lowered lpressure applied V'to the jet atA that opening, checks inthe jets to prevent flow of air under atmospheric.: pressure through them to the fuel chamber, 'andmeans to controllably vary the amount of vacuum applied to the fuel, chamber, said means embodyingl an adjustable choke.in said opensaid ,vaccumconnection leads,

In witness that I claim the foregoing I have hereunto subscribed my name this th day of October 1920. v

^ EDWARD-F. SHERRICK.

Images