US1803684A - Carburetor - Google Patents

Description

May 5, 1931. v 1.. M. WOOLSON 1,303,684

GARBURETOR Original Filed April 21, 1923 Patented May 5, 1931 UNITED res PATENT, oFF-icr.

LIONEL M. WOOLSON, OF DETROIT, IvI ICBIG-AN, ASSIGNOR T0 PACKARD MOTOR CAB, C0211- PANY, OF DETROIT, MICHIGAN; A COFPORATION OF MICHIGAN onnsunriroa Original application filed. April 21, 1923, Serial No. 633,595. Divided and this application filed January 11,

' vide a carburetor which will supply unvar ing amounts of fuel for any successive units of time under normal'ope'ratin'g conditions.

Another object of theinvention is to pro vide a carburetor in which the liquid fuel is supplied thereto under a substantially constant gravity head not afi'ected by the carburetor suction.

Another object of the invention is to provide a carburetor with varying amounts of air dependent upon the suction and with a sub stantially constant flow of liquid fuel.

Another object of theinventio'n is to provide a novel and practical carburetor for.

feeding extremely small quantities bustible mixture. 7 v V 3 Other objects of the invention 'will appear of com from the folloi'ving descriptiontaken in conv nection with the drawings, which form a part of this specification, and in which:

Fig. 1 is a general View, partly in elevation and partly in section, illustrating the invention as applied to an internal combustionengine, the section through the lower carburetor part of the view being taken substantially on the line 1-1 of Fig. 2; and r Fig. 2 is a section substantially on the line 22 of Fig. 1, the dust cover. being removed.

Internal combustion engines as built today for automobile use, are usually supplied with some means for heating the mixture which is supplied by the main carburetor of the'motor to the cylinders thereof. One of such means is known as a combustion heater or tuelizer and it consists generally of a combustion chamber having an outlet in the motor intake Serial No. 80,687.

pipe between the throttle Valve and the cylinders and having a spark plug or other means made to build a combustion heater of this type for use generally on motors of several different forms and with carburetors andmtake passages of different types, considerable 'difficultyarises and heretofore it has not "been practical to so build and supply combustion heaters.

The present invention contemplates supplying the engine With its mixture'irom the main carburetor and supplying the combustion heater with its mixture from another and differently acting carburetor whereby the engine may be operated with a richer mixture from the main carburetor when idlingjthan When running with the" throttle partlyhor fully open and the combustion heater may be supplied with a leaner mixture When the engine is idling than When the engine is running on partly or fully open throttle; It Will be understood that the combustion heater operates at its maximum when the motor is operating at its minimum because it is at that time that the greatest amount of heatis required for the mixture, the motor supplying its own heat very largely when it is operating at partly or fully open throttle. I

The invention further contemplates the use of a carburetor for supplying combustible mixture to the combustion heater in Which the liquid fuel is supplied at a substantially unvarying rate under normal operating conditions While the air for the car buretor is supplied at a varying rate, dependent upon the suction.

One form of the invention is illustrated in the drawings hereof. Referring thereto, 10 represents an internal combustion engine or the cylinder block thereof and 11 is the intake conduit which supplies the mixture to the engine cylinders. A throttle valve of the butterfly type is shown at 12, it being understood that this valve is usually manually controlled and the operator opens and closes it as he desires a greater or less amount of mixture to be fed to the engine.

13 represents generally the main carburetor which is connected to the intake conduit 11 to supply a combustible mixture thereto for the engine. It comprises the usual float chamber 14, a nozzle 15 which is supplied with liquid fuel by the float chamber, a mi:\' ture tube 16 surrounding the nozzle and supplied with air by the main air intake passage 17, and an auxiliary air intake passage 18, which is controlled by a valve 19 and a spring 20 which is usually adjustable. A butterfly valve 21 is arranged in the main air passage for choking the air supply when starting in cold weather. The float chamber maintains the liquid fuel at the desired level just below the top of the nozzle 15, in the usual way, and it is supplied with gasoline from a tank 22 through a pipe 23.

In this type of carburetor the valve 19 is usually so adjusted that it is closed when the motor is idling and a richer mixture is then supplied to the engine than is obtained when the throttle valve is opened and the suction is sufficient to open the valve 19 against its spring. The carburetor therefore will supply a somewhat richer mixture when idling than when rui'ming on partly or fully open throttle and this is desirable because a richer mixture is required to operate the engine smoothly when idling.

The burner part of the combustion heater shown in Fig. 1 comprises a combustion chamber 24 formed in a suitable casting which is screwed into the intake conduit 11 between the throttle valve 12 and the engine cylinders. This threaded attachmentis shown at 25 and the chamber 24 has an outlet into the intake conduit in the form of a pipe 26 having a cup 27 attached to its lower end, the pipe being formed with lateral openings 28 into the cup, thus providing a circuitous passage for the exhaust gases from the chamber 24 into the intake conduit 11. A spark plug 29 is secured in one side of the chamber 24 and an inlet cap 30 is screwed in the top of the chamber and provided with a glass window 31 through which the operation of the burner may be observed. The inlet cap 30 retains a screen 32 in place over its inlet passage 33 and a pipe 34 is connected with the inlet cap for supplying mixture to it.

The carburetor part of the combustion heater or the device for supplying combustible mixture to the combustion chamber 24 of the burner is indicated generally at 35. It is supplied with gasoline or other liquid fuel from a tank 36 through a pipe 37. The tanks 22 and 36 may be the same or different tanks.

The carburetor is shown as mounted on a support 38 as by the bolts 39 extending through ears 40 formed on the casting of which the carburetor is made. The outlet of the carburetor is connected to the pipe 34 as at 41.

The casting 35 is formed with a plurality of vertically extending chambers or wells numbered respectively 42, 43, 44, and 46, the latter of which communicates with the pipe 34 as above stated. A dust cover 47 is secured over the upper ends of the other chambers, being secured to the casting as by screws 48 and being provided with air openings 49 and 47 so that the upper ends of these chambers are always open to the atmosphere.

The chamber 42 is a reservoir or float chamber of rather usual form, there being a float 50 mounted therein and controlling a valve 51 which thereby regulates the level of the gasoline in the chamber 42. The gasoline or other liquid fuel enters the chamber 42 through the pipe 37 above referred to, the screen 52, and a port 53 which the valve 51 controls. The level of the liquid is indicated at 54.

The screen 52 above referred to is secured to a movable plug 55 so that the screen may be readily cleaned. The screen is preferably of fine mesh so that dirt may be kept from the float chamber and the consequent clogging of the outlet from the float chamber prevented.

One of the greatest difliculties heretofore encountered in the making of a small carburetor, or a carburetor adapted to supply a small quantity of mixture is that the outlet from the float chamber or the fluid inlet to the carburetor, must be made so small that it is impracticable from a commercial viewpoint. This is because said inlet has heretofore been subjected to part or all of the suction of the engine and the flow of liquid fuel, therefore, into the carburetor is greatly increased as the suction of the engine increases.

In the present invention an inlet orifice of practical size is used and it is subjected to only the gravity head of the chamber to which it is connected, in the present case the float chamber 42. This orifice is so far removed in effect, from the chamber which is subjected to the engine suction, that said suction has no appreciable effect whatever upon the flow of liquid fuel through the orifice and thus the orifice delivers unvarying amounts of fuel for any successive units of time under normal operating conditions.

The outlet orifice from the float chamber indicated at 56. It is formed in a plug 57 t threaded into an opening between the flea.

chamber 42 and the adjacent chamber 43, so

that the orifice 56 connects those chambers.

formed in the casting opposite' the plug 57.

The chamber 43 communicates with tie' chamber 44 by means ofan orifice'or passage 60 at the lower ends of thecha1nbers,'and the chamber 44 communicates with chamber 45 through a similar passage 61. Each of these passages (SO-and 61 is preferably larger than the passage or orifice 56 so that there is free passage for all of the fuel that may be fed by the orifice 56. I

v A somewhat larger-passage 62 connects the chamber 45 at its lower end so that the liquid fuel may be ted tothe inside of the nozzle.

he nozzle 63 has an opening 64 at its lower end and it extends upwardly in the chamber. 46 to a contracted part 65 thereof and the upper end of the nozzle also is slightly above the normal level 54 of the tuel 1n the float chamber 42. I

An air passage 66 extends between the upper ends of chambers 45 and 46, for diluting the mixture formed in the upper part of chamber 46, and this passage'is regulated by a valve 67 which is in the nature of a plu jor bolt as shown particularly in Figs. 1 and 2. The bolt extends to the outside of the casting as shown particularly in Fig. 2 and after being set in any desired position it is locked by a nut 68 thereon.

The operation ofthis carburetor may be described as follows: lVith the internal combustion engine at rest so that there is no suc tion through the burner chamber 24 of the fuelizer and the pipe 34 which connects the latter with the carburetor 35, the liquid level in the carburetor is as indicated in Fig. 1,

this level being the same in all of the cham-.

bers 42, 43, 44, 45 and 46. \Vhen the engine is turned over for starting, with the throttle valve 12 nearly closed, there will be suction in the pipe 34 and consequently in the upper end of the chamber 46. This suction will draw some air through the valve opening 66 and considerable gasoline from the lower part of the chamber 46, thus passing a rich mixture to the pipe 34, and consequently to the chamber 24 of the combustion heater. This rich mixture will be ignited by the spark plug 29 and will continue for some time as ends the suction on the chamber 46 will be considerably more than in the chamber 45 and in the latter it will be more than inthe chamber 44 as the chamber 44 is emptied of gasoline through the passage 61. As the gasolineflows outof chamber 43 through the passage '60the depression or suction of chamber 46 is so far reduced through the success si-ve chambers that the chamber 43 is practically at atmospheric pressure. 1 The flow of gasoline, therefore, into chamber 43 through the orifice 56 is due entirely to the head of liquid in the float chamber 42 and it is not attected in any way b'y-the suction of the mixing chamber 46.

It will be seen, therefore, that after the chambers or wells 46, 45, 44 and 43'have had their supplies of gasoline exhausted by the initial operation of the engine, the sole supply or gasoline to the mixing chamber 46 will come from the orifice 56 which is under a low head of gravity pressure only and with the passages 60 and 61 so much smaller than the open upper ends of chambers 45 and 44, the continued operation of the engine draws air through those chambers and with it the small quantity of gasoline passing through the orifice 56 into the chamber .43. Thereafter,

as the suction increases, more air will be drawn through the cascadeof vertical chame bers and yet the same quantity of gasoline per unitof time will be delivered to the carburetor and consequentlythe mixture will be leaner than on'the lighter suction. In other words, the carburetor will feed a relatively lean mixture to the combustion chamber.:24 I

under high suction and a relatively rich mixture thereto under low suction, and the degree of richness may be adjusted within limits by turning the air valve 67 which controls the port or passage at the upper ends ofthe chambers 45 and 46. This means that the combustion heater will operate on a relatively lean mixture when the motor isidlin g and is consequently being fed a rich mixture the main carburetor13 and a somewhatricher mixture will be fed to the combustion chamber 24 when the suction through the combustion heater isless, as when the throttle valve 12 is partly or fully opened. 'With this lesser suction through the ch amber 24the somewhat richer mixture is desirable because or the lesser speed-oi the gas through the chamber 24. Moreover, the'heater is not re quired to supply so much heat under those conditions as when the motoris idling because the motor itself will supply. enough heat when the throttle is partly or fully open.

While I haveherein describedin some de tail a specific embodiment of my invention, which I deem to be new and advantageous and may specifically claim, I do not desire it to be understood that my invention is limited to the exact details of the construction. as it'willbe apparent thatchanges maybe made therein without departing from the spirit or scope of my invention.

Having thus described my invent-ion, what 1 claim and desire to secure by Letters Patent is:

1. A carburetor adapted to carburet only unvarying amounts of fuel for any successive units of time under normal conditions, including in combination a mixing chamber, aconstant level fuel reservoir having communication with said chamber to supply fuel thereto by gravity, and means to render ineffective on said reservoir any suction effect in said chamber, whereby fuel is furnished said chamber at an unvarying rate.

2. A carburetor adapted to carburet only unvarying amounts of fuel for any successive units of time under normal operating conditions including in combination, a mixing chamber, a fuel reservoir having a relatively small orifice below the fuel level in communication with said chamber, said ori fice being the only fuel outlet from said reservoir and means to render ineffective on said orifice any suction effect in said chamber.

3. A carburetor comprising in combina tion, a constant level fuel reservoir having a small outlet orifice disposed below said level, said orifice being the only fuel outlet from said reservoir, a mixing chamber having a fuel inlet orifice, and fuel feeding means between said orifices comprising a plurality of chambers open to the atmosphere and having a restricted communication with each other.

4. A carburetor comprising in combination, a constant level fuel reservoir having a small outlet orifice disposed below said level, said orifice being the only fuel outlet from said reservoir, a mixing chamber, and means providing communication between said orifice and said chamber including a plurality of wells communicating with each other through restricted orifices and being open to the atmosphere.

5. A carburetor for a combustion heater comprising in combination, means to supply fuel at a substantially constant rate, and means to mix air with said fuel in amounts varying with the suction, whereby a richer mixture is obtained under low suction conditions than under high.

6. A carburetor comprising in combination, a constant level fuel reservoir, a mixing chamber under suction, and means to conduct fuel from the reservoir to said chamber at a substantially constant rate, said means comprising a series of atmospheric chambers directly connected through restricted open ings and each adapted to further reduce the suction on the preceding chamber of the series.

7. A carburetor comprising in combination, a mixing chamber under suction, a fuel reservoir adapted to supply fuel to said chamber under a constant head. and a connccting means therebetwecn adapted to substantially eliminate the suction effect of the chamber on the reservoir, said means comprising a series of restricted passages connected by chambers under atmospheric pres sure.

8. A carburetor comprising in combination, a constant level fuel reservoir having a small outlet orifice disposed below said level, said orifice being the only fuel outlet from said reservoir, a mixing chamber under suction, and means including a series of chambers open to the atmosphere and connected through restricted openings to conduct fuel from said reservoir to said chamber at a constant rate.

9. A carburetor comprising in combination, a constant level fuel reservoir having a small outlet orifice disposed below said level, a mixing chamber under suction, and means to supply fuel from the reservoir to said chamber at a constant rate including a series of chambers open to the atmosphere and directly connected through restricted openings.

In testimony whereof I afiix my signature.

LIONEL M. VOOLSON.

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