US2795214A - Combined fuel injection and ignition system for internal combustion engines - Google Patents

Description

June 11, 1957 T. w. SHOOK n 2,795,214

COMBINED FUEL INJECTION AND IGNITION SYSTEM FOR INTERNAL COMBUSTION ENGINES Filed May 20, 1955 fi e. 2.

. INVENTOR T kur'si'on W Shoo/7c .H.

ATTORNEY COMBINED ,FUEL INJECTION AND IGNITION FOR INTERNAL COMBUSTION EN- "Tlrur'ston W. Shook-II, Columbus, Ohio vApplication: May 20, 1955, Serial No. 509,933

' '5 Claims. cries-42 -The present invention relates to fuel injection and ignition systems for internal combustion engines and more particularly to a combination fuel injector and ignition device for internalcombustion engines intended to replace the usual carburetor and spark plug devices commonly employed in internal combustion engines.

The usual internal combustion engine employed with present-day automotive'vehicles includes a carburetor for mixing-liquid fuel, such as gasoline, with air in desired proportions whereby to provide anefiicient combustible mixture for timed introduction within the cylinders of the. engine and for firing or igniting by a spark developed through a spark plug associated witheach cylinder of the engine.

It has been proposed in the past, particularly in connectionwithdieseltype' internal combustion engines, to employ fuel injecting systems wherein controlled charges of raw liquid fuel areinjected under pressure into the cylinders at timed intervals to be ignitedby the heat andpressure developed in such cylinders through compression of air therein by a reciprocating piston; Also it has beenproposed toemploy fuel injection systems withinternal combustion engines of the'type incorporating-spark plug or electrical ignition devices for igniting a fuel air. mixture Within the internal combustionren- :gine. However, in these latter systems, .the fuel injectionnozzles-andpump mechanisms are provided as separate units from the spark plug elements, andare generallyactuated bypressures derived from engine-driven pumps. Generally, such prior fuel injection systems,

whileoperating with improvedefiiciency, as compared with the usual carburetion system, :are relatively expensive and structurally complex, with the result that. the installationof fuel injection systems on ordinary combustion enginesof the type employed in connection with automotive vehicles has not reached any great extent.

The primary object of the presentinvention is to provide a combined fuel injection nozzle or pump and fuel igniting device adapted particularly for use in"ordinary types of internal combustion engines, and in replacement of the usual carburetor and spark plug devices normally found in such engines.

It. is another object of the .inventionto provide a combined fueli-injectingand ignition device which is adapted to be operatively connected with thecylinderof the engine after'the manner of theusual'spark plug, and which functions electrically to inject liquid fuel into-the cylinder of the engine, and substantially immediately ignite such fuel within the cylinder for power developing automotive vehicle.

Yet another object of theinvention .isto provide-ea combined fuel injecting and ignition whereinsthe quan- Patented June 11, 1957 tity of fuel injecteddn to the cylinderof an associated engine may be controlled through the manual adjustment of an electricalresistance typerheostat connected in the ignition circuitfor the engine, thereby providing a relatively simple and efiicient throttle control for theengine.

A still further object of the present invention is to provide a relatively compact and structurally simple fuel injecting and ignition devicerconstructed and arranged so. as to be operatively installed on the ordinary automotive vehicle internal combustion engine in replacement for the usual spark plug device, and which comprises forming acomponent=partof the fuelinjecting and ignition device. 1 Y

For a further more .detailed understanding of the present invention and the additional objects and advantages ambient therein, refercnceis made to the following description and the accompanying drawing, wherein:

Fig. 1 is a medial vertical sectional view taken through a combined fuelinjecting and igniting device formed in accordance with the present invention, and showing the associated electrical circuit in diagrammatic form;

Fig.2 is a horizontal sectional view taken along the line 2- -2 of Fig. l;

'Fig. 3 is an enlarged fragmentary vertical 'rsectional view taken through'the fuel rdischargingnozzle of the device.

Referring to thedrawing by reference characters, the numeralll designates a cylinderpof a conventional 4-cycletype internal combustion engine in which a piston ,2 is arrange to reciprocate. The cylinder head includes the usual threaded spark-plug-receiving:opening 3 in which the present combined fuel-injecting and igniting device is positioned and supported, and thecylinder is provided with the usual intake and exhaust valves, not shown.

As exemplary of a presently preferred form of -rny device, the same comprises a metallic base member-4 of hexagonal nut formation having an integral, depending,

1 6, and shouldered for engagernentywith'theseat a'tliereof, is'a molded dielectric body member7-which is preferably formed from a porcelain ceramic fused andboiided to the metal base member '4.

Thebody 7 is formed in thellower part .thereofwith an axially extending passage 8 which terminates .in -.a

relatively enlargedcylindrical chamber 9. Extending through the passage '8. is an injectionrcylinderlbar'relltl, the latter opening at its upper endwithin t-hechamber9 and being. formed at its lower end with -.a conical fuel at'omizing .spray nozzle. 11 which projectssintoithe. outer end portion of theengine cylinder 1. The barrel-10 is formed with allateraljly extendingfuel inljet port 12, which extends exterior'lyof the body for connection with a fuel supply .line'13' through which liquid'fuel un'der pressure of a fuel pump P is conducted-- to theinlet port 12. Thesupply line 13 is provided with a check valve 14 whichfunctions to perrriit free-'flow of fuel to'theinlet port 1=2-- while 'precludingfiow in the opposite-direction. g r

Mounted to reciprocate: within the upper end portion of ..-the.;cylinder.vbarrel 10 is a pump: piston" or plunger 3. 15 preferably formed in whole or in part from soft iron. The upper end of theplunger 15 terminates in across head 16 which is formedwith spacedguide openings 16a slidably mounting the cross head 161011 the. shanks of a pairof stationary, headed,guide posts 17 extending outwardly from the end of thebody 7. Theposts 17 are threaded at their inner ends and are carried in screw-threadedsockets 18 formed in thebody 7. Compression-type coil springs 19 are carried on the shanks of the post members and are disposed between theupper surface of the body member and the under surface of thecross head 16, thesprings 19 imparting upwardly directed biasing forces to the cross member and thepump plunger 15.

Positioned in thechamber 9 of the body member is asleeve 20, and around the outer surfaces: of this sleeve there is disposed a magnetic field coil or winding 21. When thecoil 21 is energized, theplunger 15 is attracted by the magnetic field thus established so that theplunger 15 is forced downwardly, against the resistance offered to such movement by thesprings 19, to forcibly inject a charge of liquid fuel contained in the lower part of the barrel into the associatedengine cylinder 1 for admixture with compressed air within said cylinder whereby to provide an explosive fuel-air mixture without the use of 1 a conventional carburetor. The initial position of the plunger in thebarrel 10 and the tension of thesprings 19 may be adjusted by threadedpost member 17 to determine the maximum pumping stroke of theplunger 15. It will be understood that upon the down stroke of theplunger 15 in producing fuel injection, the check valve 14 is seated and closed against fuel: transmission.

Projecting outwardly fromthe lower end of thebase member 4 is a grounded electrode 22 which is bent at its outer end to terminate substantially in closely adjacent relationship to the spray nozzle 11. Disposed in opposed, relatively closely spaced relation to the electrode 22 .is asecond electrode 23, the latter being anchored within thedielectricbody 7. The twoelectrodes 22 and 23 are arranged to provide a spark producing means for igniting fuel within thecylinder 1, as will be hereinafter more fully described.

Carried on one side of thedielectric body 7 are a pair of relatively spaced stationaryelectrical contacts 24 and 25. Theupper contact 24 is electrically connected by a lead 26 with one end of the field coil or winding 21. The opposite end of the winding 21 is grounded, as at 27,to themetallic base 4 by means of a conductor28 which is preferably embedded in thedielectric body 7. The opposite contact member 25 is electrically connected with alead 29 which extends through thebody 7 and is connected at its opposite end with theelectrode 23. The twocontacts 24 and 25 are preferably embedded within the dielectric material of thebody 7 and are spaced apart from one another a distance sufiicient to prevent arcing upon imposition of electrical current upon either of the contacts. Thebody 7,adjacentthe contacts 24 and 25, is provided with a laterally offset shoulder por-.

tion 30 which is spaced from the remainder of thebody 7 to provide a chamber or recess 31 adjacent thecontacts 24 and 25.. Mounted upon the laterally offset. extension 30 of thedielectric body 7 is a U-shapedstationary contact 32 provided with ascrew connector 33.

Arranged for movement. betweenthestationary contact 32 and thecontacts 24 and 25 is a movablemetallic bridge element 34 carried upon adielectric post support 35 carried in depending relation to one side of theplunger cross head 16. The movable bridge,element 34 is sized so as to closely fill the gap or space betweenthe U-shaped contact 32 and the opposed contacts.24 and .25, and when positioned in horizontal registrybetween the respective limbs of thecontact 32 and theopposed contacts 24 and 25, serves to electrically connect either of thecontacts 24 or 25 with thecontact 32.

Theconnector screw 33, associated with thestationary contact 32, is provided with alead wire 36 which extends to and .is electrically connected with one of the stationary contacts of the usual motor-drivenignition distributor 37. Thedistributor 37 is, in the usual manner, provided with a number of stationary contacts or posts corresponding in number to the number of cylinders of the associated engine, and embodies the usual rotor 38 which functions to selectively distribute ignition current in timed operation to the respective stationary contacts of the distributor. The ignition circuit further includes theusual induction coil 39 which is connected to. receive operating current from the storage battery 40, or generator of the vehicle. not shown.

Electrically connected between thecoil 39 and the rotor 38 of thedistributor 37 is avariable resistance 41 having a manuallyadjustable rheostat arm 42. By adjusting thearm 42 of theresistance 41, the magnitude of current flowing between thecoil 39 and the rotor 38 of the distributor may be varied within limits, and as will be hereinafter explained, this variable resistance provides a convenient and simplified throttle control for the present fuel injecting and ignition device.

In operation, as the rotor 38 of thedistributor 37 moves into contact with the stationary contact point of the distributor connected with thelead 36, current passes from thecoil 39 through theresistance 41, thestationary contact 32,bridge element 34,contact 24, and energizes the coil or field winding 21. Energization of thecoil 21 results in forcible downward movement of thecoreplunger 15 to cause fuel contained within thecylinder barrel 10 to be forcibly injected into thecylinder 1. Simultaneously with the movement of theplunger 15, thebridge element 34 moves downwardly out of registration with thecontact 24 and into bridging relation between thecontacts 32 and 25, thus causing current to pass through thelead 29 to theelectrode 23 where a spark gap is produced between theelectrodes 23 and 22 to ignite the fuel just previously injected into the cylinder 1.1

It will here be understood that the capacity of the coil or field winding 21 must be such as to cause substantially instantaneous movement of theplunger 15 andbridge element 34, but the extent of movement or travel of theplunger 15 andbridge element 34 may be varied within limits by adjustment of thevariable resistance 41. For example, when it is desired to inject a maximum quantity .of fuel within thecylinder 1, theadjustable arm 42 of the rheostat or resistance is positioned so as to bypass or provide a minimum amount of resistance in the circuit, thus increasing the amount of current imposed on the coil or winding 21. Since the strength of the magnetic field produced by thecoil 21 is directly proportional to the amount of current imposed thereon, theplunger 15 may be caused to move on a maximum stroke determined by the spacing between thecross head 16 land the upper end of thebody 7 against the resistance afforded such movement by thesprings 19. Conversely, by increasing the resistance within the circuit by adjusting thearm 42 for maximum resistance, the current imposed on the winding 21 will be decreased with a resultant decrease in the stroke of theplunger 15, and a consequent decrease in the amount of fuel injected into the cylinder '1.

, It will here be understood, that in order to provide firing or ignition, regardless of the length of stroke of theplunger 15, the spacing between thecontacts 24 and 25 must be sufliciently close to insure firing on each injection stroke, and toward this end, the spacing between thecontacts 24 and 25 is proportioned in accordance with a minimum stroke of theplunger 15. For this reason, the width of the lower contact 25 and the lower limb of thestationary contact 32 is substantially greater than the width of theupper contact 24 and upper limb of thestationary contact 32 in order to insure the establishment of a spark between theelectrodes 22 and 23 regardless of variation in the stroke. of..theplunger 15. a

Adv-antageously, the adjustingarm 42 of the rheostat orresistance 41 may be employed as a throttle for the associated engine, and toward this end may be mechanically linked with the usual accelerator pedal of the associated vehicle, not shown.

It will be understood that a multiple cylinder engine will, of course, employ one of the present combined fuel injecting and igniting devices for each cylinder, and that the various stationary contacts of thedistributor 37 will be appropriately connected with thestationary contact 32 of each of the devices employed with the several cylinders. Similarly, while the pump P has been illustrated diagrammatically in association with a single fuel injecting and igniting device, it will be understood that such pump may through proper manifold arrangement, not shown, be utilized to supply fuel under pressure to a plurality of the present fuel injecting and igniting devices.

In view of the foregoing, it will be seen that the present invention provides a structurally simple yet highly eflicient combination fuel injecting and igniting device for internal combustion engines which is capable of injecting variable charges of fuel within the cylinders of such engine through the relatively simple adjustment of an electrical rheostat control.

The combined fuel injecting and igniting devices of the present invention eliminate the necessity for the usual carburetor and spark plug elements of an internal combustion engine, and at the same time greatly increase the efiiciency of the associated engine due to the substantially simultaneous injection and firing of'fuel within the cylinders of the engine as the piston elements closely approach or reach a top center position, enabling the associated engine to operate on so-called lower grade fuels, such as kerosene. The close arrangement of the injection nozzle and spark-producing electrodes results in substantially instantaneous ignition of the fuel immediately following injection thereof within the cylinder, and when such devices are placed substantially along the center line of the associated engine cylinders, the fuel air mixture tends to burn radially outwardly with respect to the cylinder, thus resulting in increased power-producing efficiency of the engine.

While I have disclosed and described in detail a single preferred embodiment of the invention, it will be understood that various modification as to details of construction and design may be resorted to without departing from the spirit of the invention or the scope of the following claims.

I claim:

1. A combined, unitary, fuel-injecting and igniting device for an internal combustion engine comprising a body member arranged to communicate at one end with a cylinder of an internal combustion engine; electro-responsive fuel-injecting pump means carried by said body member and having a fuel-discharging outlet at one end of said body member, said pump means being operable upon energization to forcibly discharge fuel under pressure from said outlet; electrode means carried by said body adjacent said fuel-discharging outlet and operable upon energization to produce ,a spark for igniting fuel discharged from said outlet; and switch means carried by said body member and including a switch element movable in association with said pump means for establishing first an energizing circuit for said pump means and secondly an energizing circuit for said electrode means.

2. A combined fuel-injecting and igniting device for an internal combustion engine comprising a supporting body; a fuel injection pump mounted in said body and including a pump cylinder having a fuel inlet disposed intermediate the ends thereof and a fuel-discharging outlet projecting outwardly from one end of said body and a reciprocating pump plunger carried within said pump cylinder and movable to forcibly displace fuel between the inlet and outlet of said pu-mp cylinder; electro-responsive means carried by said body and energizable to move the plunger of said pump on an injection stroke; spark-producing electrode means carried at said one end of said body and energizable to produce a fuel-igniting spark adjacent the outlet of said pump cylinder; and a switch carried by said body having connection respectively with said electro-responsive means, said electrode means and a source of electrical energy, said switch including an element movable in association with the plunger of said pump and arranged for movement to successively establish energizing circuits first for said electro-responsive means and then for said electrode means.

3. A combined fuel-injecting and igniting device as defined inclaim 2, wherein the plunger of said pump is formed at least in'part of soft iron, and said electroresponsive means comprises a magnetic field winding arranged on said body so as to attract said plunger upon energization and to move said plunger within the cylinder of said pump in a direction to forcibly eject fuel fro-m the fuel-discharging outlet of said pump.

4. A combined fuel-injecting and igniting device as defined inclaim 2, including means electrically connected with said switch for varying the electrical input thereto from a source of electrical current, and thereby to vary the amount of energizing current introduced into the energizing circuit for said electro-responsive means.

5. A fuel-injecting and igniting device for internal combustion engines, said device comprising a unitary body structure removably receivable in the normal spark plugreceiving opening provided in the cylinder head of an internal combustion engine, said structure including an internal fuel-injecting cylinder formed intermediately of its length with a fuel inlet and at one end of said structure with a fuel-discharging outlet; a plunger slidably mounted in said cylinder and movable to forcibly eject fuel from the outlet of said fuel-injecting cylinder; spring means cooperative with said plunger to maintain the latter normally in a retracted fuel-admitting position in said cylinder; electrically energized means cooperative with said plunger element to move the same in a fuel-ejecting direction in said cylinder against opposition of said spring means; spaced spark-producing electrodes carried by said body structure and disposed contiguous to the fuel-discharging outlet of said cylinder; and switch means carried by said body structure and having separate connection with said electrically energized means and said electrodes, and having a movable switch element arranged to move in association with said plunger for establishing successive operating circuits for said electrically energized means and said electrodes.

References Cited in the file of this patent UNITED STATES PATENTS 1,134,537 Hutches Apr. 6, 1915

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