US1082466A - Carbureter for internal-combustion engines. - Google Patents

Description

0. 1 LI] OAS. GABBURETEB. FOR IN'IERNAL COMBUSTION ENGINES. APPLICATION FILED JUNE 3, 1913.

1,082,466, v g: Patented Dec.23,i913.

m TNESSEJ.

vented certain new and useful nmrnn snares. PATENT mm;

OWEN DAVID LUGAS, F BAYSWATER, 130m, BHG'LAH D.

' .cmnnnrns, non mrnnmincomane'rron ENGI ES.

Specification of'l'iefiers latent.

Patented;Dec.23,1 913.

Application filed June 3, 1913. serialll'o. 771,471.

To all whomit may concern Be it known that I, Owen DAVID LUCAS, a subject of His Majesty the King of England, residing at Bayswater, in the county of London, Kingdom of England, have in- Improve meats in Carburetors for I'nternalQombustion Engines, of which the following a.

specification.-

This invention has reference to improve ments in carburetors for internal combustion engines, and its object is to provide a more perfect mixture under all conditions of engine load and speed than has heretofore been attained.

The invention-has to do particularly with that type of carburetor described in my application filed on March 18, 1911, Serial No.

615,29 t, wherein there is provided a jet sitnoted in a jet .chamber, as distinguished from the mixing chamber proper, the jet chamber communicating w th the mixing chamber by suitable orifices. In the corbu reter of theaforesaid application the mixing chamber is exposed to the direct suction of the engine, there being no throttling means between the mixing chamber and en gine, while the air snpply'is controlled by 'a mechanically ariable port between the.

mixing chamber and the atmosphere. The

i suction on thejet, and consequently the amount of hydrocarbon admitted to the mixing chamber. is in the structure shown. in the aforesaid application controlled by a mechanically variable port between the jet chamber and the atmosphere, the arrangement being such that if the effective area of the air po i t to the. mixing chamber is being increased, that'of the air port of the jetchamber is being correspondingly diminished, and vice versa.

According to the presentinvention means are-provided for \controlhngthe suction of the jet by -mechanica lly vary ng the size of the orifice through which communication is had between the jet and mixing chambers and the arrangement isalso, such that whe the effective area of the air port of the mixing'chamber is bemg enlarg the orific between lzhejet and mixing chambers is in- 50 creased in effective area, and vice versa, while the port between the jet chamber and the atmosphere remains constant, Again, the variable orifice between the jetand mixing chambers may be employed in a carburcter Where the-air portsof the jet and mice derstanding that while the drawings show a practical form of the. invention, the latter is not confined to any strict conformity with the showing of the drawings but may be changed and modified so long as such changes and modifications mark no material departure from the salient featuics of the invention.

' In the (l1-a\vings:---Figure l isa diagram illustrating the invent-ion in its simplest adaptation. Fig. 2 is a similar diagram illustrating the invention as embodied in 1 I carbureter operating according to the aforesaid application. j

Referring to the drawings there is shown a carburetor provided with a mixing or secondary-air chamber a coimnunicating with the -atmosphere by an air port '0 and with the cylinder is of an engine by aninduction pipe 1'. There is, also provided a jet or pr1mary-air chamber-d entered at the lower portion by a jet j which may be considered as fed by a constant level'float feed device such as'colnmonly employed in carbureters. The chamber 1 communicates directly with the atn'iosphere byway of .a port e lo ated at a pointdistant from the i t The port 0 iswntrol d-e tear chambers.

- the suction of thejet is by a throttle-f which is'simply'indicated as a sliding throttle and may be arranged to either control the port 0 alone, as in Fig. 1 5 or to simultaneously and oppositelvcontroii. the ports-c and e, as in Fig. 2. echam -v 'bers a and d communicate through an orifice. l, which may be either singleor multiple, it being, sometimes advisable to, have the orifice Z composed of a'number of small passages, but in any. event the area of the orifice 1, whether single orrmultiple, is small or minute as compared with the ports e and 0, and particularly the port a. In the structure shown in the aforesaid application this orifice: is of constant area at all times, while the control of the suction of the jet is afiected by a manipulation of the throttle common to the air ports oj both the. jet and In accordance with theresent invention rther controlled by a shutter o adapted-to .vary the efiective area of the orifice 1 between the two cham bers d and e and so arranged that when the port a isincrea'sed or diminished in effective area the orifice I will be varied in efiective area in the same sense as the port a. In Fig. l. the'port e remains constant durin the adjustments of the port a and orifice In. Fig. 2 the port 0 and orifice Z-are increased or diminished in efiective area in the same sense,'while the port 6 is diminished in effective area as t e port 0 and orifice] are increased in effective area, and is increased 'in effective area as the port a and orifice l are diminishedin effectivearea. The move- .ments' of the two control shutters f and 0 may be caused in any suitable manner, and this may be brought about by any suitable bperatingmeans, such as indicated in the drawings, where there is shown a bell-crank lever g, pivoted at h and connected ,bylinks a, z", to .the shutters or --valves f and a, respectively. 'An'operating link a connected to the lever 9 may extend to any convenient point. I

When the engine piston is moving on the suction stroke, subatmospheric conditions are produced within the chamber a and simi? lar conditions are also produced in the chamber (1, since these two chambers are. in'communication by: way of the orifice l,

v and while both chambers may. each be in communication with the atmos herethrough the respective air ports,c an e there are still such subatmospheric' conditions in, the chamber-d that there is caused'an. inflow of fuel through'ithejet' j and this is -met,by air, which'may be termed primary air, en-

teringtherhambertlthrough the air port-e and vthe-primary: air and .fuel pass into the mambem amugh the oricel which isof eitl've area here the diluting ort c is met and a suita le mixture is efected. Theair port of the chamber a is ;.so situated that when it is decreased in effcetive area 'thedegree of subatmospheric pressure in the chamber a caused by the suction of the .engine tends to increase, wherefore a similar condition arises in the chamberd in the structure shown in Fig. 1 and this'condition may be increased or diminished by varying the effective area of the orifice l. In the structure shown in Fig. 2 'the air port of the jet or primary air chamber decreased in efiective area as the air port-to the chamber a is increased and .vice .versa, and while a decrease of the effective sizeof the air port 0 tends to increase the suction at the jet 7' this tendency is to an extent counteracted by the simultaneous opening oi the port e, which under these circumstances becomes a jet. controlling port. The action of the air ports and its throttle on the jet is opposite to the manner in which a throttle operates when it is laced, as is customary, in the suction pipe etween the jet and the engine.

The action of the jet is modified by increasing or diminishing the effective area ofthe orifice Z and increasingor diminishing of the efi'e'ctive area of the air port 0 both in thesame sense, and under some circumstances the action is further modified by the decrease or enlargement of the effective area of the port e with the increase or decrease of the elfective area of the port a, this is in the opposite sense thereto.

What 'is claimed is 1. A carbureter, for internal combustion engines, provided with two separate chambers, one chamber having means for freeconstant communication with the engine and also provided with an air port opening directly to the atmosphere, and the other chamber having an' air ort opening directly to the atmosphere and also having a 'fuel inlet in the lower portion'thereof, said chambers being in direct communication through 'a small orifice located on substantially the level of the mouth of the jet, and said orifice and the air port of the first-'namedchamber bein provided with throttling means for regu atin'g their efiective areas and movable in the same sense. 2. A carburetor, for internal combustion engines, provided with two separate cham bers, one chamber having means for free constant communication with the engine and also provided with an air nbrt opening chamber havin an air portopeningjdirectly to the atmosp ere and also havin a fuel inlet in the lower portion thereof, said chambers being-in directcommunication through or secondary air enterin 'by way of the i directly to the atmosphere, and the' other a small orifice located on substantially the the opposite sense to the movements of the level of the mouth of the jet, and said orifirst-named throttling means. 10 fice and the air port of the first-named In testimonywhereof I have signed this chamber being provided with throttling specification this 21st da of Mayl9l3. 5 means for regulating their effective areas OWEN AVID LUCAS.

and movable in the same sense, the air port Witnesses: v of the second-named chamber being also JNo. D. ELKIN, provided with throttling means movable in GEORGE I. Bnmens.

Images