US2102909A - Internal combustion engine - Google Patents

Description

C. R. PATON INTERNAL COMBUSTIONENGINE Filed Feb. 1, 1955 TWIN 1% Patented Dec. 21, 1937 UNITED sm'rss PATENT OFFIE INTERNAL COMBUSTION ENGINE Application February 1, 1933, Serial No. 654,608

9 Claims.

This invention relates to internal combustion engines and more particularly to the mixture control mechanism for such engines.

In startinginternal combustion engines, it is 5 necessary to enrich the mixture fed to the cylinders and, for this purpose, most engines are equipped with choking devices which result in the formation of a combustible mixture rich in fuel. Under certain conditions, such as when the choke l mechanism is manually operated, it has been found desirable to connect the throttle, which controls, the volume of combustible mixture, to the choke mechanism so thatthe engine will tend to develop more speed or power while choked 15 and thereby remind the vehicle operator that the engine is still choked, thus serving to prevent long continued engine operation under choked conditions, which, it is well known, re-

sults in excessive fuel consumption, oil dilution,-

O and consequent motor wear. However, in using a device of this nature, I have found that the throttle valve is sometimes too widely opened by the choke mechanism and thereby results in the formation of too lean a mixture for satisfactory starting and I have, therefore, connected the engine starting system to the throttle valve in such a way as to render the choke connection to the throttle valve ineffective while the starter is operating and effective immediately thereafter. 30 One of the objects of this invention is to enable the starting mechanism to make the mixture richer than the choke mechanism is able to do. Another object of the invention is to enrich the combustible mixture supplied to an engine during the starting period without increasing the amount of mixture available until after the starting period is over, at which point it is proposed to automatically increase the amount of mixture fed to the engine to a; predetermined 40 amount, which amount shall be sufficient to maintain combustion under extreme temperature conditions.

A further object of the invention is to so control the mixture fed to the engine during opera- 45 tion of the starting system, and thereafter, that the volume of the mixture will be increased, and its richness decreased, immediately after the engine is started.

Another object of the invention is to provide a fuel feeding system with automatic means for increasing the supplied mixture by a predetermined amount as soon as the starting system is thrown out of operation.

A 'still'further object of the invention is to 5 provide a fuel feeding system with automatic means for increasing the air fuel ratio in the combustible mixture fed to the engine as soon as the starting system is thrown out of operation.

Other objects of theinvention will appear from the following description taken in connection With the drawing, which forms a part of this specification, and in which:

Fig. 1 is a partly sectioned view of a carburetor on a plane perpendicular to the throttle axis with which is associated a starting system;

Fig. 2 is a section on the line 22 of Fig. 1;

Fig. 3 is a section on the line 33 of Fig. 1 showing a detail of the carburetor controlling mechanism;

Fig.4 is a section on the line 44 of Fig. 1 showing a portion of the carburetor; and

Fig. 5 is. a modification of a portion of Fig. 1.

Referring to the drawing, l0 illustrates a carburetor attached to an intake manifold H which in turn may be associated with an engine in the well-known manner, such as is illustrated "in Patent 1,122,121, to Huff dated December 22, 1914, so that the carburetor under the influence of the engine-induced suction in the manifold supplies the required air mixture to the engine in a man'- ner which will be more fully described. Also associated with the engine in the well-known manner as is conventionally illustrated in Patent 1,116,370, to Bendix dated November 10, 1914 is a starter system including a starting motor I! engageable in driving relation with the engine through a starting pinion [3. Suitable power means, such as a battery i l, controlled by a switch I6, is adapted to energize the starting motor. A solenoid H, the purpose of which will be more fully described hereinafter, is included in the electrical circuit through the starter and is thus energized. whenever the starter motor is operative and is de-energized upon breaking of the starter motor circuit, as by the opening of the switch l6,

More in detail, the carburetor comprises an air supply inlet 18, a throttle valve I9 mounted on a shaft 21, and a mixing chamber 22 between the air inlet is and the throttle valve.

23 is a float chamber or carburetor bowl containing a float valve, not shown, for regulating the level of fuel in the bowl. During normal running conditions, fuel is supplied to the mixing chamber 22 through a duct 24 connected, in a manner not shown, to the float chamber. Within the duct 2A is a needle valve member 26 controlling the supplyof fuel fed through the duct tothe j outlet end-of the expirating nozzle 21.

The nozzle 2! is situated between a pair of swingable vanes 28, of which only one is shown, forming a venturi. In the type of carburetor shown, the vanes pivot about their supports 29 under the influence of the engine suction and in so swinging lugs 3i, integral with the vanes, engage a groove 3P in the nozzle to raise the nozzle and the duct 24 in a direction away from the needle valve 25, thereby varying the effective size of the needle valve opening so that as the volume of air fed to the engine increases, the fuel volume will also increase, thus maintaining a fuel air mixture of the proper proportions until maximum power conditions are encountered when a power jet 32 comes into use and admits additional fuel.

The power jet is located between the vanes 28 and the throttle valve and there is still another passageway 33, serving as a priming jet, having an outlet located in the fuel feeding conduit beyond the throttle valve. Such jets form an auxiliary supply means for the fuel feeding system.

The power jet has a plurality of functions. In one position of the control means; nothing passes through the power jet. When the control means is in another position and the engine is idling, only air passes through the jet, but when the throttle has been somewhat further opened, air and gasoline are supplied by the power jet thereby increasing the richness of the fuel mixture. When the throttle is not very far open, there is a rotating valve means associated with the accelerating pump, to be described, which limits the air drawn through the power jet. Under either open or partially closed conditions, sudden opening of the throttle results in the depression of the pump, and a stream of liquid fuel is injected through the power jet.

The priming jet 33 is designed to function only when the control 41 is adjusted for engine starting. When this condition occurs, the pump just referred to operates, when the throttle opening mechanism is moved, to inject a stream of liquid fuel through the priming jet. This is sometimes done prior to operating the starter in order to get gasoline into the intake manifold. As the starter is operating with the throttle in wide-open position, the suction created by the engine in the manifold draws gasoline from the float chamber 23 through the jet 33 where it is mixed, in a rich mixture, with the air coming past the throttle valve. The starting mixture is enriched by closing of the throttle, it being understood that even with the throttle completely closed, some air is drawn past it by the manifold suction.

The power jet consists of the conduit 32 supported in the body of the carburetor and communicating with a passage 34 in a boss 35 projecting from the side of the carburetor above the bowl 23. The boss 36 is provided with an axial bore 311' within which is located an accelerating pump housing 33, the housing being freely slidable and rotatable in the bore. The housing itself has an axial bore 39 enlarged at its upper end to form a chamber 4! and communicating with four radial ports M, 42, 43, and 44 located in that part of the housing which is within the boss 36. The housing extends above the boss where it is relieved on one side to form a flat face 46, and extends below the boss to a point adjacent the top of the float chamber 23. The lower part of the pump housing 38 is fixed to an operating arm 4! and is acted upon by a spring 48, attached as at 58, to the carburetor in such a manner that the spring opposes the action of the choke operating means, such as a cable 5|, which is regulated by a suitable choke controlling mechanism. A coil spring 52, surrounding the housing and abutting the lower part of the boss 36, engages the upper part of the arm 4'! and forces the housing 38 downwardly so that its lower end engages with the top of the carburetor bowl 23. Registering with the lower end of the pump housing 38 is a sleeve 53 which projects down into the float chamber below the level of the fuel therein. The sleeve is apertured, as at 54, above the fuel level and is adapted to cooperate with the lower end of a pump plunger 56 to form the accelerating. pump means for supplying fuel to the intake manifold when the plunger 55 is depressed. For this purpose, the sleeve is provided with a gravity check valve 51 and a spring 58 which normally urges the plunger 56 upward. Thus, during the upward stroke of the plunger, fuel is drawn into the space below the plunger through the valve 5?. For operating the plunger, I have provided an arm 5% pivotally associated with the upper end of the plunger and with the throttle shaft 2i so that rotation of the shaft towards a throttle opened position will depress the pump plunger, forcing fuel upwardly through an axial bore 6| and a radial bore 62 in the plunger to the chamber 15 formed in the interior of the pump housing 32.

When the control member 47 is moved to one extreme position, as shown in Fig. 4, it is noted that the only outlet from the pump chamber 40 is the port 32 and the jet 33. When the control member 47 is in an intermediate position, ports 4!, 42 and 43 in the pump housing 38 are closed to the chamber 49, but the port 44 is open to the L 38 joins the bore 96, there is formed a shoulder 1 G5 and there is, in the wall of the pump plunger 56, a second radial bore 66 which is adapted to be uncovered by the shoulder 65 when the throttle is wide open. It will also be noticed that there is a shoulder 5'1 formed on the upper part of the pump plunger 5%.. This is adapted, when the throttle is partially open, to close the passage 4i. With the throttle in this position then, it is seen that communication between the air inlet 64 and passage 4!, leading to the power jet 32, l-

is' closed but that an air inlet has been opened through the passage 86, the aperture 54, and an air inlet E8 formed in the top of the carburetor bowl so that, with the engine running, a suction is exerted on the opening 65 and on the volume of fuel in the axial bore 6! of the pump plunger.

The opening 56 is relatively smaller than the passage E4 so that under these conditions both air and gasoline are drawn up through the axial bore 6! of the pump plunger through the upper chamber 63, the passages 43 or 44 and 34 to the power jet 32. These passages are co-related in their functioning to regulate the mixture in a desirable manner.

It is thus seen that under idling conditions the engine is fed by fuel passing through the nozzle 2.? supplemented by air passing through the power jet 32. When the throttle is more widely opened, additional gasoline is fed through the power jet 32.

Rotation of the control arm rotates, as has been previously described, the pump housing 38 and such rotation turns the fiat face 46 out of contact withpin 69 carried by an arm H on the throttle shaft 2|. 1 p

A spring 12 keeps the pin 69 in contact with the upper part of the pump housing 38' and, as

the housing is rotated, the pin 69 and spring 12 cooperate to open the throttle valve slightly.

Thus, whenever the arm 41 is in a position to cut off the air supply through the power jet 32,

rotation of the arm, also brings the passages H and 43 into communication with the passages 64 and 34 so that, as the throttle is then opened, the operation will be as described.

While it is advantageous to have a warning that the priming jet 33 is operating, it is, I have found, desirable to have a greater suction exerted on the priming jet than is possible with the throttle in the cracked-open position brought about .loy the pin 69 engaging the cylindrical portion of the pump housing. That is to say, it

is desirable to close the throttle completely while starting but, as soon as the starter ceases to function, and the engine operates on its own power, it is desirable to have the throttle resume its partially opened position so that a sufficient volume of a leaner mixture may be provided to sustain engine operation.

' For accomplishing this purpose, I provide a connection between the starting system and the throttle valve so that, while the starter is operating, the throttle will be closed and, as soon as the engine starts to run under its own power and the starter ceases to operate, the throttle valve will resume whatever position is forced on it by the auxiliary fuel feeding system.

As\ shown in Fig. .1, this connection is of an electrical nature and comprises an arm I3 rigid with the throttle shaft 2| and connected by means of a link M to a bar 16 running through the previously referred to solenoid l'l. Thus, whenever the switch i6 is closed, the solenoid will be energized to pull the arm E3 until the throttle valve is substantially closed so that a minimum of air will be drawn into the intake manifold H and so that the mixture may be at its very richest.

The effect of the solenoid I! in rotating the throttle shaft into throttle closed position is designed to overcome the force of the spring l2 so that the yieldable choke regulated throttle operating connection through the pin 69, is rendered inoperative but, as soon as the switch i5 is opened, the solenoid is de-energized and the spring 12 forces the throttle open again. The de-energizing of the solenoid l1 occurs when the starter switch i6 is opened, which in turn usually happens as soon as the engine starts to run, particularly if the starting motor circuit is automatically controlled as in the manner illustrated in my copending application Serial No. 582,806, filed December 23, 1931.

Under these conditions, the control of the throttle may be left to the automatic functioning of the mechanism which I have described and this is particularly advantageous under certain conditions where the vehicle operator is not entirely familiar with the proper degree of throttle opening necessitated by cold weather starting conditions.

Fig. 5 shows a modification of the connection between the starter and the throttle which is mechanical in nature. I have shown a pedal 11 which may be the starting pedal, for regulating the starting motor switch i5 in the desired manner. Thus, as the pedal is depressed, a shoulder 18 thereon engages a bell-crank I9 pivoted as at 86 and connected to a link 14 and the arm 13, as previously described. Thus, as soon as the starting switch is closed, the throttle is also closed and, as soon as the starting switch I5 is opened under the influence of a suitable spring such as the one shown at 8!, the spring 12 again becomes effective as it did with the electrical connection between the starting system and the throttle.

With the electrical connection, functioning of the throttle [9 through the conventional throttle operating'mechanism 82, is not interfered with because the rod 15 is free to slide in the solenoid l? and, with the mechanical connection shown in Fig. 5, the same condition occurs because the shoulder It on the pedal TI is, when the starter is notoperating, above the range of movement of the bell-crank l9.

It will thus be seen that I have provided means operative during operation of the starting system to enrich the mixture and means operative after all) the starting system has ceased to function, to

decrease the richness of the mixture.

Although the invention has been described in connection with a specific embodiment,'the principles involved are susceptible of numerous other applications which will readily occur to persons skilled in the art. The invention is therefore to be limited only as indicated by the scope of the appended claims.

What I claim is:

1. In a fuel feeding system for engines, the combination with a throttle valve, of priming means operatively connected with said valve to urge the latter into open position during the priming of said engine, and engine starter mechanism connected to substantially close said throttle valve when effective. I

2. In a fuel feeding system for engines, the combination of throttle valve means, priming means acting when effective to urge said valve means into open position, starter mechanism for said engine, and a connection actuated by said starter mechanism when effective to close said throttle valve.

3. In a fuel feeding system for engines, the combination of throttle valve means, priming means connected with the system beyond the throttle valve means, a connection between the priming means and the valve means tending to urge the valve means into open position when said priming means is rendered operative, engine starter mechanism, and a connection actuated by the engine starter mechanism when effective for closing said valve means.

4. In a fuel feeding system for engines, the combination of a means for feeding metered air and fuel, a. throttle valve regulating the volume of metered air and fuel moving through the system, an auxiliary fuel induction system beyond the throttle valve, means for substantially closing said valve during engine starting, and means coacting with said auxiliary induction system to open said throttle valve a limited extent when said closing means is released.

5. In a fuel feeding system for engines, the combination with means controlling the quantity of combustible mixture supplied to said engine, of priming means for said engine, an operative connection between said control means and said priming means for increasing the quantity of mixture supplied to said engine during priming thereof, and engine starter mechanism operatively associated with said control means for decreasing the quantity of mixture supplied to said engine when the latter is started.

6. In a fuel feeding system for vaporized charge engines, the combination with means controlling the quantity of combustible mixture of air and liquid fuel supplied to said engine, of priming means operable to supply said engine with an excess of liquid fuel to facilitate starting, a connection between saidpriming means and said control means tending to reduce the quantity of mixture supplied to said engine during priming thereof, mechanism for starting said engine, and a connection'between said starting mechanism and said control means tending to reduce the quantity of mixture supplied to said engine during operation of said starting mechanism.

7. In a fuel feeding system for vaporized charge engines, the combination with means controlling the quantity of combustible mixture of air and liquid fuel supplied to said engine, of priming means operable to supply said engine with an excess of liquid fuel to facilitate starting, a connection between said priming means and said control means tending to reduce the quantity of mixture supplied to said engine during priming thereof, mechanism for starting said engine, and

a connection between said starting mechanism and said control means tending to reduce the quantity of mixture supplied to said engine during operation of said starting mechanism, said last named connection opposing and overcoming the action of said first named connection.

8. In a fuel feeding system for vaporized charge engines, the combination with means controlling the quantity of combustible mixture of air and liquid fuel supplied to said engine, of priming means operable to supply said engine with an excess of liquid fuel to facilitate starting, a yielding connection between said priming means and said control means urging the latter to a position corresponding to increased mixture supply to said engine, mechanism for applying torque to said engine to start the same, and means associated with said mechanism opposing the action of said yielding connection when torque is applied to said engine. g

9. In a fuel feeding system for vaporized charge engines, the combination with means controlling the quantity of combustible mixture of air and liquid fuel supplied to said engine, of priming means operable to supply said engine with an excess of liquid fuel to facilitate starting, a yielding connection between said priming means and said control means urging the latter to a position corresponding to increased mixture supply to said engine, mechanism for applying torque to said engine to start the same, and an operative connection between said mechanism and said control means effective to reduce the quantity of mixture supplied to said engine to a minimum during application of starting torque to said engine.

CLYDE R. PATON.

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