US2404645A - Carburetor - Google Patents

Description

Parented July 23, 1946 UNITED STATES ATENT OFFICE 14 Claims. 1

This invention relates to a carburetor for an internal combustion engine.

Where a governor throttle valve is positioned between the manual throttle valve and the engine, then when the engine is working under no load or real lightJ loads and the governor valve is almost closed and the manual throttle valve is wide open, th'e fuel mixture becomes very lean thereby causing overheating and rolling ofthe engine which in turn causes the governor valve to surge.

It is the object of this` invention to overcome the above objection which results from the use of an automatically operated governor valve between the carburetor and the engine. This object is accomplished simply and efficiently by utilizing the intake passageway pressures. adjacent the governor throttle valve to control a power jet which opens and admits more fuel through the main jet whenever the above conditions obtain.

Fig. Lis a vertical section through my carburetor.

Fig. 2 is a fragmentary vertical section showing a modified form of the same.

The parts forming my carburetor are as follows: carburetor housing I, governor body 2 positioned` between the carburetor housing and the engine, intakey passageway It, air inlet 4, outlet to the engine 5, manually controlled throttle valve Ii preferably of the buttery type, valve shaft 1, crank arm 8 fixed on shaft l, rod 9 for controlling carburetor throttle valve 6, governor throttle valve IEI preferably of the butterfly type mounted on shaft II, float bowl I 2, fuel level I3, venturi I4, main jet I connected by passageway It with oriiice il in fuel bowl' I2, idle jets I 8 and I9 connected by passageway 26 with passageway I6, power jet 2| communicating with passageway I6 (the orifices Il and 2| are positioned below fuel level I3), needle valve 22 controlling power jet 2|, piston 23 in cylinder 24, arm 25 connecting piston 23v and valve 22, compression spring 2t tending to raise piston 23 and hold valve 22 open, passageway 2l connecting cylinder 24 with oriiice 28 positioned on the atmosphere side of valve I0 when nearly closed.

It is understood that governor valve I@ is automatically operated and may be any of the known automatically operated types of governor such as the unbalanced velocity type governor valve, the engine driven centrifugal weight actuated type of governor, or the intake passageway pressure actuated governor such as shown in my cepending application Serial No. 466,961, filed November 25, 1942.

The operation of my carburetor is as follows: As shown in the drawing throttle valve E is wide open and governor valve |Il is almost closed. Under these conditions the pressure vat orices I 8 and I9, which are the customary idle jets of the carburetor, will be substantially atmospheric and the only fuel obtained by the engine is that drawn out of main jet I5 through venturi It. With governor valve l!! nearly closed, the velocity through venturi I4 is so low that in the absence of power jet 2| so little mixture would be drawn out of main jet I5 that the mixture would become too lean. However, under the above conditions, oriiice 2.8 is on the atmosphere side of governor valve IB and in substantiallyatmospheric pressure, which pressure establishes itself in cylinder 24 belowrpiston; itV and permits spring 26 to raise piston 23 and lift needle valve 22 from power jet 2| and thereby admit more fuel through main jet I5 to the engine. As soon as valve Ii! opens wide enough to permit more air to flow through venturi I4, then orifice 28 will be positioned between governor valve Iii and the engine, that` is, in the intake passageway-vacuum. Under such engine side of valve IEI will now establish itself in cylinder 24 thereby drawing piston 23 down against compression spring 2tV and thereby closing power J'et 2|. However, closing of power jet 2| under such conditions will not cause the mixture at main jet |15 to become too lean because even though power jet 2| is closed the velocity through venturi I4 by jet `I5 will be high' due to the opening of governor valve i!) and sufficient fuel will be drawn out of main jet I5 to satisfy the fuel mixture requirements of the engine.

The modif-led form of my carburetor shown in Fig. 2 is identical with that shown in Fig, l except that passageway 21 terminates at orifice 3i! which is positioned at all times between the engine and governor valve Iii. In addition, I provide orifice 3| which is positioned between governor valve iii and Valve 6, cylinder 32, compression spring 33, orice 34 connecting cylinder 32 with the intake passageway below piston 35, piston 35, oriiice 35 between passageway 27 :and cylinder 32 above piston 35. Orifice 3| can be positioned so that it is on the atmosphere side of valve lo in al1 positions of valve ID, but preferably oriiice 3| is located adjacent valve Iii so that orice 3| is on the atmosphere side of valve I when valve lil is closed sufficiently to cause the velocity to drop so low in venturi I4 that the fuel mixture becomes too lean and in wider open positions of valve III, orifice 3l will pass onto the engine side of valve IIJ.

The operation of the modified form is as follows: When throttle I becomes nearly closed or far enough closed to cause the velocity to drop so low in venturi I4 that the mixtures become too lean, the high vacuum between governor valve II) and the engine will establish itself through'orice 34 in cylinder 32 beneath piston 35 thereby drawing piston 35 downwardly and placing orifice 3| in communication with orifice 3S and passageway 21. Since the pressure at orice 3l at this time will be substantially atmospheric, this pressure will establish itself in cylinder 24 beneath piston 23 and spring 26 will move piston 23 upwardly thereby opening needle valve 22 and permitting fuel to be drawn through power jet 2| into passageway I5 thereby enrichening the fuel mixture. When governor valve Ill opens far enough so that the velocity through venturi I4 by jet I5 will be high enough to draw sufcient fuel from orifice II and jet I5 to satisfy the fuel mixture requirements of the engine, then piston 35 will rise and shut olf communication between orifices 3| and 36 but at this time the intake passageway vacuum at orifice 3B will be established. through passageway 2l in cylinder Y24 thereby causing piston 23 to move downwardly and close valve 22. Here again the mixture at main jet I5 will not become too lean because the opening of governor valve VIll will increase the velocity through venturi I4 and draw more fuel ffrom main jet I5. Where the engine is operating under high load with both governor valve Ill and throttle valve 6 wide open, then, particularly at lower engine speeds, the power jet 2l will be open and in operation thus enriching the fuel mixture for such high load operation.

I claim:

1. In acarb-uretor for an internal combustion engine having an intake passageway, a main fuel jet in said passageway, a source of fuel connected to said main jet, a governor valve in said passageway on the engine side of said main jet, an additional fuel supply system for supplying fuel into said intake passageway including an auxiliary jet, and means actuated by changes of pressure in the intake passageway for controlling said auxiliary jet, said means responding to substantially atmospheric pressure in the intake passageway on the atmosphere side of the governor valve when nearly closed to open said auxiliary jet and admit fuel into the intake passageway.

2. In a carburetor for an internal combustion engine having an intake passageway, a power jet for supplying fuel into said passageway, a source of fuel connected to said power jet, a governor valve on the engine side of said power jet, means actuated by changes of pressure in the intake passageway for controlling said power jet, said means responding to the pressure in the intake passageway onl the atmosphere side of said governor valve when nearly closed to open said power jet and admit fuel into said intake passageway, and said means responding to the pressure in the intake passageway on the engine side of said governor valve when opened to shut off said power jet.

3. In a'carburetor for an internal combustion engine having an intake passageway, a main fuel jet in said passageway, a source of fuel connected to said J'et, a governor valve on the engine side of said main jet, a power jet for feeding fuel into said intake passageway, means actuated by changes of pressure in the intake passageway adjacent said governor valve for controlling said .power jet, a conduit connecting said pressure actuated means with the intake passageway on the atmosphere side of and adjacent the governor valve when nearly closed and with the intake passageway on the engine side of said governor valve when the governor throttle valve is opened beyond idle position to an extent where the iluid Velocity by the main jet will draw fuel from the main jetat a rate to produce a sufciently rich mixture whereby said pressure actuated means responds to the pressure in the intake passage- Y way on the engine side of said governor valve and closes said power jet.

4. In a carburetor for an internal combustion engine having an intake passageway, a venturi in said intake passageway, a main fuel jet in said venturi, a source of fuel connected to said jet, a governor Valve on the engine side of said main jet, a power jet for feeding fuel into said intake passageway, means actuated by changes of pressure in the intake passageway 'adjacent said governor valve for controlling said power jet, a conduit connecting said :pressure actuated means with the intake passageway on the atmosphere side of and adjacent the governor valve when nearly closed whereby said pressure actuated means responds to the pressure in the intake passageway on the atmosphere side of the governor valve and opens said power jet, said conduit connecting said pressure actuated means with the intake passageway on the engine side of said governor valve when the governor throttle valve is opened beyond idle position to an extent where the fluid velocity by the main jet will draw fuel from the main jet at a rate to produce a suffioiently rich mixture whereby said pressure actuated means responds to the pressure in the intake passageway on the engine side of said governor valve and closes said power jet.

5. In a carburetor for an internal combustion engine having an intake passageway, a venturi in said intake passageway, a main fuel jet in said venturi, a source of fuel connected to said jet, a

governor valve on the engine side of. said main jet, a manual throttle valve between the governor valve and the main jet, a power jet for feeding fuel into said intake passageway, means actuated by changes of pressure in the intake passageway adjacent said governor valve for controlling said power jet, a conduit connecting said pressure actuated means with the intake passageway on the atmosphere side of and adjacent the governor valve when nearly closed whereby when the manual throttle valve is wide open said pres-y sure actuated means responds to the pressure in the intake passageway on the atmosphere side of the governor valve and opens said power jet, Vsaid conduit connecting said .pressure actuated means with the intake passageway on the engine side of said governor valve when the governor throttle valve is opened beyond idle position to an extent 6. In a carburetor for an internal combustion engine having an intake passageway, a venturi in said intake passageway, a main fuel jet .in said venturi, a source of fuel connected to said jet, a governor valve on the engine side of saidk main jet, a manual throttle valve between the governor valve and the main jet, an idle jet between the. manual throttle valve and the governor valve for feeding fuel into said intake passageway when theA manual throttle valve is' closed for idling the engine, a power jet for feeding fuel into said intake passageway, means. actuated by changes of pressure in the intake passageway adiacent said governor valve for controlling said power jet, a conduiteonnecting said pressure actuated means with the intake passageway on the atmosphere side of and adjacent the governor valve when nearly closed whereby when the manual throttle valve is wide open said pressure actuated means responds to the pressure in the intake passageway on the atmosphere side of the governor valve and opens said power jet, said conduit connecting said pressure actuated means with the intake pases-igen way on the engine side of said governor valve when the governor throttle lvalve is opened beyond idle position to an extent where the fluid velocity by the main jet will draw fuel from the main jet at a rate to produce a sufficiently rich mixture whereby when the manual throttle valve is wide open saidpressure actuated means responds to the pressure in the intake passageway on the engine side of said governor valve and closes said power jet.

7. In a carburetor for an internal combustion engine having an intake passageway, a main fuel jet in said passageway, a source of fuel connected to said jet, a governor valve on the engine side of said main jet, a power jet on the atmosphere side of said governor'valve for feeding fuel into said intake passageway, a valve controlling said power jet, means actuated by changes of pressure in the intake passageway adjacent said governor valve for controlling said power jet valve, a conduit connecting said pressure actuated means with the intake passageway on the atmosphere side of and adjacent the governor valve when nearly closed whereby said pressure actua-ted meansI responds to the pressure in the intake passageway on the atmosphere side of said governor valve and opens said power jet valve, said conduit con necting said pressure actuated means with the intake passageway on the engine side of said governor valve when the governor throttle valve is opened beyond idle position to an extent where the fluid velocity by the main jet will draw fuel from the main jet at a rate to produce a suciently rich mixture whereby said pressure actuated means responds to the pressure in the intake passageway on the engine side of said governor valve and closes said power jet valve.

8. In a carburetor for an internal combustion engine having an intake passageway, a venturi in said intake passageway, a main fuel jet in said venturi, a source of fuel connected to said jet, a governor valve on the engine side of said main jet, a power jet on the atmosphere side of said governor valve for feeding fuel into said intake passageway, a valve controlling said power jet, means actuated by changes of pressure in the intake passageway adjacent said governor valve for controlling said power jet valve, a conduit connecting said pressure actuated means with the intake passageway on the atmosphere side of and adjacent the governor valve when nearly closed whereby said pressure actuated means responds to the pressure in the intake passageway on the atmosphere side of the governor valve and opens said power jet, said conduit connecting said pressure actuated means with the intake passageway on the engine side of said governor valve when the governor throttle valve is opened beyond idle position to an extent where thefluid velocity by the main jet will draw fuel from the main jet at a rate to produce a sufficiently rich mixture whereby said pressure actuated means responds to the pressure in the intake passageway on the engine side of said governor valve and closes said power jet valve.

9. In a carburetor for an internal combustion engine having an intake passageway, a main fuel jet in said passageway, a source of fuel connected to said jet, a governor valve on the engine side of said main jet, a power jet for feeding fuel into said intake passageway, means actuated by changes of pressure in `the intake passageway adjacent said governor valve for controlling said power jet, an orice positioned in the intake passageway o-n the atmosphere side of and adjacent the governor valve when nearly closed to a position so that the fuel drawn from the main jet by the air flowing past said jet providesa too lean mixture, a conduit connecting said pressure actuated means with said orifice whereby the governor valve in closing reaches said above specified position the pressure `actuated means responde to the pressure in the intake passageway on the atmosphere side of the governor valve and opens said power jet, said orifice passing on to the engine side of the governor valve when the governor valve is opened to a position where the air now by said main jet will draw suiiicient fuel through the jet to produce a proper fuel mixture whereby said pressure actuated means responds to intake Ypassageway pressure and closes said power jet.

l0. In a carburetor for an internal combustion engine having an intake passageway, a main fuel iet in said passageway, a source of fuel connected to said jet, a governor valve on the engine side of said main jet, a power jet for feeding fuel into said intake passageway, means actuated by changes of pressure` in the intake passageway adjacent said governor valve for controlling said power jet, an orifice positioned on the atmosphere side of and adjacent the governor valve when closed to a position where the air flow by the main jet will draw fuel from the main jet at a rate to produce a too lean mixture, a second orifice. positioned at all times on the engine side of the governor valve, a conduit connecting said first and second orifices with said pressure actuated means, a valve actuated by changes of pressure in the intake passageway on the engine side of said governor valve for controlling said rst mentioned orifice, said pressure actuated valve closing said rst mentioned orifice whenever the governor Valve is opened sufficiently to bring said first mentioned orifice on to the engine side of said governor valve, said pressure actuated Valve opening said iirst mentioned orifice when the governor valve is closed sufficiently to bring said first mentioned orifice on to the atmosphere side of said governor valve whereby said pressure actuated means responds to the pressure in the intake passageway on the atmosphere side of said governor valve and opens said power jet.

11. In a carburetor for an internal combustion engine having an intake passageway, a throttle valve, a main fuel jet in Ysaid passageway on the atmosphere side of said throttle valve, a source of fuel connected to said jet, a governor valve on the engine side of said main jet, a power jet for feeding fuel into said intake passageway, means actuated by changes of pressure in the intake passageway for controlling said power jet, an

orice positioned in said intake passageway between the governor and throttle valves, a second orifice positioned at all times on'the engine side of the governor valve, a conduit connecting said first and second orices with said pressure actuated means, a valve actuated by'changes of pressure in the intake passageway on the engine Y si'de of said governor valve for controlling said iirst mentioned orice, said pressure actuated valve closing said first mentioned orifice whenever the throttle valve is substantially wide open and the governor valve is opened suiiiciently to cause the fluid velocity by said main fuel jet to draw sufficient fuel from said main jet to produce a sufficiently rich mixture, said pressure actuated valve opening said first mentioned orifice when the throttle valve is substantially wide open and the governor valve is closed sufficiently to cause the velocity to drop so low by the main jet that the fuel mixture becomes too lean whereby said pressure actuated' means responds to the pressure in the intake passageway on the atmosphere side of said governor valve and opens said power jet. f

12. In a carburetor for an internal combustion engine having an intake passageway, a throttle valve in said intake passageway, a, main fuel jet in said passageway on the atmosphere side of said throttle valve, a source of fuel connected to said Ymain jet, a, governor valve in said passageway on the engine side of said throttle valve, an additional fuel supply system for supplying fuel into said intake passageway including an auxiliary jet, and means actuated by changes of pressure in the intake passageway on the engine side of said throttle valve for controlling said auxiliary jet, said means responding to substantially atmospheric pressure in the intake passageway on the atmosphere side of the governor valve when nearly closed and when said throttle valve is substantially wide open to open said auxiliary jet and admit fuel into the intake passageway.

13. In a carburetor for an internal combustion engine having an intake passageway, a throttle valve in said intake passageway, a main fuel jet in said passageway on the atmosphere side of said throttle valve, a source of fuel connected to said main jet, a governor valve in said passageway on the engine side of said throttle valve, an additional fuel supply system including an auxiliary jet for supplying fuel into said intake passageway on the atmosphere side of said throttle valve, and

means actuated by changes of pressure in the intake passageway on the engine side of said throttle valve for controlling said auxiliary jet, said means responding to substantially atmospheric pressure in the intake passageway on the atmosphere side of the governor valve when nearly closed and when said throttle valve is substantially wide open to open said auxiliary jet and admit fuel into the intake passageway, saidV means also responding to substantially atmospheric pressure in the intake passageway such as occurs when both the governor and throttle valves are substantially wide open and the engine is operating under high load.

14. In a carburetor for an internal combustion engine having an intake passageway, a main fuel jet in said passageway, a source of fuel connected to said main jet, a governor valve in said passageway on the engine side of said main jet, an additional fuel supply system including an auxiliary jet for supplying fuel into said intake passageway on the atmosphere siderof said governor valve, and Vmeans actuated by changes of pressure in the intake passageway for controlling said auxiliary jet, said means responding to substantially atmospheric pressure in the intake passageway on the atmospheric side of the governor valve when nearly closed to open said auxiliary jet and admit fuel into the intake passageway, said means also responding to substantially atmospheric pressure in the intake passageway such as occurs when thegovernor valve is in wide open position and the engine is operating under high load to thereby open said auxiliary jet and admit fuel -into the intake passageway.

MARION MALLORY.

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