US2153598A

US2153598A - Internal combustion engine

Info

Publication number: US2153598A
Application number: US72223A
Authority: US
Inventors: George K Steward
Original assignee: Individual
Current assignee: Individual
Priority date: 1936-04-02
Filing date: 1936-04-02
Publication date: 1939-04-11
Anticipated expiration: 1956-04-11

Description

April 1939- G. K. sfEwARD 2,153,598

INTERNAL COMBUS T ION ENGINE Filed April 2, 1936 INVENTOR. George K. Sfe Ward.

Patented Apr. 11, 1939 UNITED STATES PATENT OFFICE Application April 2,

19 Claims.

This invention relates to improvements in internal combustion engines, and especially to means and the method of. igniting and burning fuel gas or combustion mixture therein to control detonation. I

Heretofore detonation, which is objectionable, has been controlled by producing turbulence, or in other words, violent mixing of the power charge. This has been accomplished in one instance by special construction of the intake manifold, in another instance by special construction of the cylinder head. In both of these instances, however, the turbulence period precedes the ignition of the charge, and to such a degree that the turbulence has been considerably reduced prior to actual ignition of the charge.

An object of the present invention is to produce turbulence of the charge by and during the ignition thereof to thus initiate turbulence and enhance it during the combustion period.

To this end the method of this invention consists in preparing a comparatively small quantity of gas consisting of a higher percentage of oxygen than is contained in the gas of the power charge,

and preparing another small quantity of gas having a still higher percentage of oxygen than that contained in the first mentioned quantity, then igniting the first quantity of gas, using the fire thereof to ignite the power charge by piercing it with a plurality of flame torches of high speed ratio directed from the first quantity of burning gas and extending it in difierent directions into the power charge to initiate turbulent combustion thereof, and igniting the auxiliary charge or second quantity of gas and utilizing it to enhance the torch flame propagation and projected, turbulent combustion initiated by the first charge.

The means to carry out the present invention 0 includes a primary chamber in which the first charge of gas is ignited, and a, secondary chamber in which charge of high percentage of oxygen is fired, these chambers being independent of each other and independent of the usual com- 45 bustion chamber. The primary ignition chamher. and the secondary ignition chamber are herein shown as included in the spark plug.

Features of the invention also relate to the spark plug.

Other features and advantages will hereinafter appear.

' In the drawing which forms part of fication:

Fig. 1 is a central section through the greater the speci- 55 part of a spark plug embodying the invention;

1936, Serial No. 72,223

Fig. 2 is a vertical section of a portion of a motor showing the spark plug applied thereto;

Fig. 3 is a detail sectional view of the valve for air intake of the spark plug;

, Fig. 4 is a. face view of the check element of the air intake valve;

Fig. 5 is a sectional, top plan view taken on the line 5-5 of Fig. 1;

Fig. 6 is a view of a portion of the spark plug, partly in section, the section being taken on the line 6--6 of Fig. 5; and

' Fig. 7 is a view similar to Fig. 6, the section being taken on the line 'l-'I of Fig. 5.

Similar reference characters represent similar parts throughout the several views.

The spark plug includes a casing or shell or body III in which there is held an insulator II by a sleeve nut I2 threaded into the upper end of the shell I, gaskets l3 and I 4 being interposed between shoulders I5 and I6 of the shell and nut respectively, and cooperative shoulders I! and iii of the insulator.

The shell I0 is provided with a threaded portion I9, to readily screw into a threaded hole 20 in the water jacket 2|, of the motor casing 22, until it is tightly seated against a shoulder 23 formed on an annular portion 24 of the shell, the usual gasket being used under the shoulder '23 of the spark plug. A center electrode 25 and a ground electrode 26 are provided to produce the electric are between them.

Upon the down stroke of a piston 21 in a, cylinder 28 the intake valve head 29 israised, in the usual well known manner, and a fresh charge of fuel gas is drawn into the combustion chamber 30. At the same time air is drawn through a check valve 3| into a chamber 32, herein shown as formed in the spark plug. This supply of air clears the chamber 32 of any carbon, lead, or dead gas and furnishes the chamber with a volume of air. The volume of air taken in through the valve 3| may be slightly greater than the capacity of the chamber 32 thus causing some of the air to pass into another chamber 33 in which the

electrodes

25 and 26 are housed, the

chambers

32 and 33 communicating with each other through an annular passage 34 formed by the nose 35 of the insulator H and an annular shoulder 36 formed on the interior of the shell Ill.

During the succeeding compression stroke of the piston the fuel gas, taken into the combustion chamber, is compressed thus causing some of it to pass into chamber 33, through angularly disposed orifices 31 and a central orifice 38 formed in the nose 39 of the shell l0, said nose being located inside the combustion chamber 30 and being clear of the motor casing. The plug shell remains at an approximate thermal balance throughout the operation of the motor, and the .fuel gas passing through

orifices

31 and 33 is heated and its speed of flow increased, thus finely atomizing and expanding it. This prepares a mixture in the chamber 33 which will burn with a speed much greater than that of the combustion speed of the power charge in the combustion chamber 30.

The shell In is also provided with two canals 40 extending into it from the nose 39 and terminating in the near end of the chamber 32 whereby fuel gas under compression is alsoadmitted to the chamber 32, but in a smaller percentage because of the air already in the chamber 32. The gas admitted through the canals 40.

is highly atomized and thermally expanded and because of the high percentage of oxygen of the charge in chamber 32, this charge which is under compression, has a tremendously rapid burning ratio as compared to the burning speed of the heavy power charge in the combustion chamber 30, and its burning speed is also more rapid than that of thecharge in chamber 33 which has a smaller percentage of oxygen contained therein.

The charge in chamber 33 is ignited by a spark produced by the

electrodes

23 and 23 at the proper time in the cycle of operations of the motor. This ignites the charge in the primary chamber 33 which burns at high speed, expands greatly and is projected, through the

orifices

31 and 33, in torches of flame throughout the power charge in the combustion chamber 30, thus producing a condition of high speed projected, turbulent combustion-reaching various portions of the power charge-simultaneouslyand also progressively and extending to remote parts of the combustion chamber. This causes a more uniform and rapid spread of the fire through the power charge, which results in combustion which is far superior to that heretofore produced in combustion chambers of internal combustion motors.

The burning of the charge in the chamber 33 also ignites the charge in chamber 32, and since the charge in chamber 32 has a high percentage of oxygen and consequently burns with a burning speed which is much higher than the ordinary speed of flame travel of ordinary combustion; it enhances the condition of projected, turbulent combustion initiated in the ignition chamber 33.

Wall effect, or in other words the tendency of the walls to keep the gas in contact therewith or in close proximity thereto, from burning, is also limited or greatly reduced by projected turbulent combustion.

From the foregoing it will be understood that the ignition starts in the chamber 33 at the

electrodes

25 and 26. Fire is projected from both ends of the ignition chamber, downwardly and outwardly through the

orifices

31 and 33 in a plurality of torches of, high speed flame travel, into the power charge in the 30, and upwardly into the Because of its percentage of oxygen the charge in the ignition chamber 33 is of greater burning speed than that of the power charge as herein before mentioned and is of slower burning speed than that of the charge in the enhancing chamber 32. This results in longer burning in the enhancing chamber 32.

ignition chamber 33 than in the chamber '32, and

this method of combustion chamber Briefly the electricspark ignites an especially conditioned charge in primary chamber 33. The fire of this charge ignites the more highly conditioned charge in secondary chamber 32, and then the charges of both

chambers

32 and 33 combine to project combustion, at a speed much higher than that of the combustion of ordinary fuel gas, into the power charge so as to produce intense, turbulent and progressive combustion simultaneously in various parts of the combustion chamber 30.

The consumed gas is exhausted from the cylinder, during the succeeding up stroke of the piston, in the usual manner, and a fresh charge is supplied to the combustion chamber, as above described, upon the next down stroke of the piston. It will be remembered that during the intake stroke of the piston air is drawn into the chambers 33 and'32 through the check valve 3|.

The nose 3301' the plug is out of direct contact with water jacket 2| and consequently its temperature is considerably higher than that of the water jacket .and thus highly efilcient in conditioning the fuel gas which is forced through the canals 40 into the chamber 32 which has previously received one volume of air through valve 3 I. The fuel gas while passing through the canals 40 is thus heated sufiiciently to produce ebulli-.

tion or flashing thus making the gas lighter or in other words reducing its density. As the gas advances in the canals its temperature rises somewhat and the temperature of the nose is caused to drop slightly by the gas, thus producing an automatic thermal balance of the nose by gas regulation. The fuel gas which passes through the

orifices

31 and 38 is alsoheated bythe nose 33.

Due to its construction, the nose practically eliminates the possibility of oil contacting with the insulator, thus fouling of the plug, due to carbon in the lubricating oil, or-to the iron conparts, is minimized.

The

orifices

31 and 33 and the canals 40, in addition to serving to stimulate gas characteristics in chambers '32 and 33 also induce the gas to so influence various shell temperatures that the entire plug is given a semi-automatic thermal balance which varies advantageously to meet changing speed and load conditions of the motor. This of course is in a predetermined ratio to the normal water jacket regulation.

It will be understood that since air is admitted to both chambers 32 and33, but less in the latter chamber, and that fuel gas is admitted to both of these chambers, to the one through canals 40 and to the otherthrough the

orifices

31 and 38, that there are employed two systems of carburation and that both of these are in the spark plug.

The shell I! is made quite thick at 4| so as to provide a quantity of metal whereby thermal equilibrium of the nose 33 is maintained. In other words the thick portion ll of the shell, because of its contact with the water jacket 2|, keeps the nose from becoming too hot, which may'otherwise occur due to repeated firing, and.

portion 24 of the plug shell so that the air may tent therein, resulting from wear of the motor,

pass, through said aperture 44 and orifice 43, into a chamber 45 containing a check element 46. The latter is provided on its hemispherical face 41 with a groove 48 through which the air may pass, in case the check element 46 seats itself against the face 45 to a passage 49 through which it is admitted to the chamber 32. normal operation, while passing through this valve 3|, the air becomes heated beyond the flash point of the gas, thus preventing condensation of the gas in the chamber 32 while the air is mixing with said gas. During compression stroke and fire stroke of the piston the check element 46 of the valve 3|, is forced against the inner end of the screw 42 to close the orifice 43 thus preventing escape of the gas from the chamber 32. It should be understood that the air, taken in through the valve 3|, has some effect of regulating the temperature of the insulator.

The valve screw 42 is adjustable about its axis so as to vary the position of the orifice 43 with respect to aperture 44 in the shell thus varying the quantity of air drawn into the plug to thus vary the percentage of oxygen in the charge of the chamber 32 in accordance with the work of the motor in which the spark plug is to be employed. For example in a high speed motor a greater percentage of oxygen is required in the gas mixture of chamber 32 than is required in a low speed heavy duty motor.

The charge in chamber 32 burns clean (with out soot or other deposit) and at terrific speed, and in addition to enhancing the conditions of projected, turbulent combustion started by the charge of chamber 33, it tends to purge chamber 33 of iron, carbon and lead and prevent fouling by any of these. It also has a cleaning effect on the exposed shell portions, within the combustion chamber, spark plug holes, and adjacent surfaces. This makes for efficiency since it permits making the spark under the most favorable circumstances in chamber 33. This also gives the electrodes at longer life and insures good motor performance as changing spark characteristics influence motor performance less than 1 in plugs of the ordinary type.

Practically all fuel gases in use today contain at least a, small quantity of lead and this frequently causes lead fouling ofthe insulator by I attaching itself to the insulator and frequently amalgamating with the glaze thereon and thus breaking down the dielectric. This kind of fouling has never been successfully overcome and in many instances has necessitated frequent cleaning of the plugs. The present invention, however, prevents lead fouling because of the plugs low thermal rating characteristics and because of the frequent purging of the chambers 32 and The end 35 of the insulator II is so located with respect to the open end of the chamber 32 that a portion of the insulator is swept clean of foreign matter by the passage of the burning fiame. of tremendous speed, and high pressure,

through the. annular passage 34 at each firing operation. This assists in maintaining the necessary dielectric character of'the insulator. The high speed fire moving through the passage 34 is also directed towards the electrodes 25 and 2B and tends to keep them clean and thermally balanced. l 4

Because the electrodes are not depended upon to fire the power charge, butchiefiy to ignite the firing charge in chamber 33 the insulator ltmay In a be designed to be cool enough to prevent the tendency of lead to cling to the insulator and thus assist to prevent lead fouling. This also prevents one form of preignition, caused in other spark plugs when their insulators are over leaded.

It will be understood thatin each engine cycle there is athree phase ventilation of the spark plug by air, by gas and by flame to automatically purge the

chambers

32 and 33. breathing effect in this spark plug as in others. Consequently smothering, which is produced by unburned gases usually resulting from wall effect in the combustion chamber, is eliminated. This ventilation also prevents wall effect in the spark plug through increased internal turbulence.

Due to the purging by air no dead or unburned gas is left in the spark plug cavities as in other types of spark plugs, thus eliminating one'necessity for constructing spark plugs with a delicate thermal balance which requires carefully selected installation according to the classification.

Because of the arrangement of

electrodes

25 and 23 with respect to the

orifices

31 and 38 said electrodes may readily be cleaned by sand blast or other means, without taking the spark plug apart, in case it fouls. due to a deposit thereon which may result from failure to spark resulting from some cause other than the spark plug itself. However, since the spark plug is composed of three principal pieces, shell, III, insulator, II, and nut, it may readily be taken apart if necessary.

The requirement of atomic stimulation at the

electrodes

25 and 26 need not be as greatyin the spark plug of this invention, as-that of other spark plugs to produce motor efficiency and therefore the electrodes are less subject to crystallization which results in longer life of the spark plug than heretofore. I

' From the above it will be understood that detonation is controlled by a plurality of torches of high speed flame travel which pierce the power charge in the combustion chamber and thus break up the unit front advance of flame propagation, or in other words, the tendency of a flame to grow in all directions, in unit formation, from a source, by starting combustion in various locations in the combustion chamber simultaneously, which combustion grows with great turbulence throughout the entire'power charge. This simultaneous ignition in various regions of the combustion chamber by the torches of high speed flame travel, also reduces localized hot spots which are objectionable because they aggrevate detonation trouble. The turbulence produced by high speed projected combustion in addition to limiting wall effect, also limits condensation of the fuel gas which condensation eilects the lubricating oil of the motor. It also helps to more adequately fire the heavy ends of the fuel charge. The'superior combustion produced by this invention also allows a. slightly later ignition timing without loss of motor performance or efliclency.

'It will be understood that the spark plug of this invention is universal in thermal application to motor requirements because high speed live flames are depended upon to fire the compare-- tively heavy power change in the cylinder instead of the spark from a delicately balanced and often misapplied, fixed, thermal rating plug as hereto-.

There is no itself to the heat ranges of various motors with out the sacrifice of motor emciency or fouling. In other words the same spark plug may be used, under different conditions in various motors where heretofore it has been necessary to use separate spark plugs of different design to meet the condition of the motor.

Having thus described the invention it will be further understood that variations may be resorted to without departing from the spirit of the invention defined in the appended claims.

I claim:

1. The method of controlling detonation of a power charge in'an internal combustion engine, which includes the preparation of two firing charges, auxiliary to the power charge, igniting one of the firing charges, utilizing the ignited charge to ignite the power charge and the other firing charge, and utilizing the last named firing charge to enhance the ignition effect of the first ignited charge on the power charge.

2. The method of controlling detonation of a power charge in an internal combustion engine, which includes the preparation of a primary charge consisting of a mixture of fuel gas and an ingredient having a higher percentage of oxygen than that contained in the power charge, and a secondary charge consisting of a mixture of fuel gas and a higher percentage of oxygen than that contained in the primary charge, igniting the primary charge to thereby start turbulent combustion of the power charge, igniting the secondary charge by the fire of the primary charge, and utilizing the fire of the secondary charge toenhance the turbulent condition started by the primary charge.

3. The method of controlling detonation of a power charge in an internal combustion engine which includes the preparation of a primary charge consisting of a mixture of fuel gas and an ingredient having a higher percentage of oxygen than that contained in the power charge, and a secondary charge consisting of a mixture of fuel gas of a higher percentage of oxygen than that contained in the primary charge, igniting the primary charge, dividing the fire of the ignited charge into a plurality of torches of fiame to thereby ignite the power charge in a plurality of places to start turbulent combustion of the power charge, igniting the secondary charge by the fire of the primary charge, and utilizing the burning secondary charge ,to increase the travel of the divided fire to thus enhance the turbulent com.- bustion started in the power charge,

4. The method of controlling detonation of a power charge inan internal combustion {engine which includes supplying fuel gas and air separately, compressing the fuel gas and mixing some with the air and forming two separate charges with higher percentage of oxygen in one than in the other and both with a higher percentage of oxygen than the fuel gas of the power charge, igniting the charge containing the lower percentage of oxygen, igniting the power charge by the fire of the ignited charge, igniting the charge containing the higher percentage of oxygen to produce fire of high speed flame travel, and utilizing this fire of high speed flame travel to enhance the effect of the fire of the previously ignited one of said two charges.

5. In a spark plug for an internal combustion engine, the combination of means forming a primary chamber, means forming a secondary chamber, means to admit air from the exterior of said plug into the said chambers during each intake of the engine, means to admit fuel gas into the primary chamber from said engine, means to admit fuel gas into the secondary chamber from said engine, and electrodes in the primary chamber to ignite the charge therein to thereby ignite a power charge and also ignite the charge in the secondary chamber. 6. In a spark plug, the combination of two elements, namely a shell and an insulator, a nose at one end of said shell, the insulator extending into said shell from the other end thereof, a shoulder on one of said elements, said shoulder forming with the other element two chambers with a. narrow passage between them, an air inlet valve associated with one of said chambers, and electrodes in the other chamber, said nose having apertures therein extending into both chambers.

7. In an internal combustion engine having a combustion chamber into which may be introduced a power charge, the combination of means to form an initial firing charge, means to form a secondary firing charge, and means to ignite the initial charge to produce fire to ignite the power charge and the secondary firing charge.

8. In a spark plug for an internal combustion engine, the combination of a shell, and an air intake valve in said shell, said valve including a screw having an aperture extending into it from the side thereof and out from, the inner end of said screw, said shell having an aperture communicating with the aperture in said screw, said screw being adjustable about its axis to set the aperture therein with respect to the aperture in the shell to thus regulate the quantity of air to be taken in through said valve.

9. In a spark plug for an internal combustion engine, the combination of a shell having a chamber in its wall, and an air intake valve in said chamber, said valve including a screw having an aperture extending through it to the inner face thereof through which air is admitted, and a check element supported independently of said screw, said check element being operable by pressure from within the plug to engage said inner end of said screw to close the aperture.

10. The method of controlling detonation of the power charge in an internal combustion engine which includes the preparation of a primary charge consisting of a mixture of fuel gas and an ingredient having a higher percentage of oxygen than that contained in the power charge, and a secondary charge consisting of a mixture of fuel gas and a higher percentage of oxygen than that contained in the primary charge, igniting the primary charge to thereby start turbulent combustion of a power charge, igniting the secondary charge by the fire of the primary charge, and separating the fire of the primary charge into a plurality of torches having high speed fiame travel to penetrate the power charge.

11. In a spark plug for an internal combus tion engine, the combination of a shell, an insulator extending into said shell and forming therewith two communicating chambers with a narrow passage between them, means whereby fresh air may be admitted into one of said chambers, said shell having apertures therein extending from both chambers and opening into the combustion chamber served by the spark plug, and electrodes in one of the communicating chambers.

12. The method of controlling detonation of the power charge in.an internal combustion engine, which includes the ignition of a primary auxiliary charge to ignite the power charge and initiate turbulence thereof utilizing the fire oi the primary charge to ignite a second auxiliary charge, and then utilizing a second auxiliary charge to enhance the ignition effect of the pri-, mary auxiliary charge to thus increase the turbulence initiated in the power charge by the primary auxiliary charge.

13. The method of controlling detonation oi the power charge in an internal combustion engine, which includes simultaneous ignition and production of turbulence oi the power charge,

' and then enhancing the turbulence of the power charge during the remainder of its combustion period.

14. time method of producing turbulent combustion or a power charge in an internal combustion engine, which consists in propagating a series of torch like flames through the power charge, and increasing the travel of the flames aiter they have been initiated and during the combustion period of the power charge.

15. The method 01 controlling detonation oi the iuel charge in an internal combustion engine, which consists in igniting the power charge and then enhancing the travel 0! the fire through the power charge.

16. In an internal combustion engine having a combustion chamber, the combination of means forming two auxiliary chambers having a constricted communicating passage between them, an air inlet valve associated with one of said auxiliary chambers, ignition means in the other auxiliary chamber, and means forming apertures extending from the combustion chamber,into both auxiliary chambers.

17. The method oi igniting the power charge of an internal combustion engine which consists in igniting a plurality oi firing charges in sequence to each other and thereby creating a eumulative expulsive eilect serving to enhance the ignition eiIect of the combined firing charges on the power charge.

l8. Ina spark plug for an internal combustion I engine, said spark plug having a shell, said shell 7 having an air passage therein, and an adjustable device in said shell and having an aperture therein, said device being settabie to adjust its aperture relatively to said passage to regulate the quantity of air through said aperture independently of engine pressure conditions.

19. In an internal combustion engine having a combustion chamber into which may be introduced a power charge, the combination of means in which is formed an initial firing charge, means in which is -formed a secondary charge, there being a constricted communicating passage from one to the other of said means, and means to ignite the initial charge independently of the secondary charge to produce fire to thereby ignite the power charge and also ignite the secondary charge through said communicating passage.

GEORGE K. STEWARD.