US2203669A - Internal combustion engine chargeforming device - Google Patents

Description

June 11 1940. F D. BUTLER 0 INTERNAL COMBUSTION ENGINE CHARGE-FORMING DEVICE Filed May 1a, 1958 l lll q Patented June 11, 1940 UNITED STATES INTERNAL COMBUSTION ENGINE CHARGE FORMING DEVICE Frank David Butler, United States Navy Application May 16, 1938, Serial No. 208,217

2 Claims.

(Granted under the act of March 3, 1883, as if amended April 30, 1928; 370 0. G. 757) My present invention relates to charge-forming devices for internal combustion engines-more particularly of the type wherein the fuel used in such engine is atomized, and injected into the l combustion chamber of such engine automatically by the compression and combustion pressures present in such combustion chamber, and wherein such fuel is ignited during such injection by the intense heat generated in said I. combustion chamber as the supply air charge is highly compressed therein by the engine piston as the latter nears the completion of its compression cycle period of operation. The solution of the major problem of burning oil fuel efilll ciently (especially in relatively small piston dis- .25 bination with an internal combustion engine and as an article of manufacture, contemplate; (a) theprovision of relatively inexpensive and efficient means for minutely atomizing, highly agitating and injecting the fuel charge into the combustion chamber of each cylinder of such engine automatically and pneumatically by and through the compression and combustion pressures within such combustion chamber or chambers; (b) the provision of means for bleeding off sufficient compressed air or combustion gas from said combustion chambers via said fuel injecting unit necessary for the pneumatic operation of the latter; (c) the provision of means for cushioning the automatically operated moving elements of said fuel injecting unit as they near the ends of their reciprocating travel; chanical means for remotely regulating the quantity of fuel per injection charge of said fuel injecting unit, and remotely and collectively regulating the quantity of fuel injection charges when more than one unit is used (as when used in multi-cylindered engines); (6) the provision of hydraulic means (especially adapted to radial aviation engines) for remotely and collectively regulating the quantity of fuel per injection charge per cylinder; .0) the provision of means combining provisions a, b and c with either d or e into a single fuel atomizing and injecting unit; and (y). the provision of means comprising minor new and useful-entities which practically, com- (d) the provision of memercially, efllciently, and economically practice, 1 in the manner found by me thus far in the development 'of my invention to be most advantageous in each of the foregoing, and other respects which will more clearly appear, and be'understood by those skilled in this'art, from the accom panying drawing and the following description,

and appended claims.

It will be readily appreciated by those skilled in this art, after understanding my invention, 10 that various changes may be made-'in the means disclosed herein which will produce the same results in practically the same manner without digressing substantially from my inventive concept or sacrificing any of its outstanding inherent advantages. r

With'reference to the drawing- Fig. 1 is a plan view of Fig. 2.

Fig. 2 is a longitudinalsection (as would appear on the dotted lined-2 of Fig.l) of my automatically'and pneumatically operated, mechanically remotely regulated fuel atomizing and injecting unit and illustrates the automatically operated moving elements of such unit in their closed or normal position of travel, and-the me- 2 chanically remotely regulated elements of such unit in their half fuel charge position of regulation. 1

Fig. 3 is an enlarged portion of thelower end of Fig. 2 except illustrating the automatically operated moving elements of the fuel injecting unit in the position they would occupy at the completion of the fuel injection period and prior to their return to their closed or normal positio of travel. 33

Fig. 4 is a portion of a longitudinal section of my automatically and pneumatically operated, hydraulically remotely regulated fuel atomizing and injecting unit and illustrates the automatically operated moving elements of such unit 4' in their open. position of travel, and the hydraulically remotely regulated elements of such unit in their half fuel charge position of regulation.

Fig. 5 is an enlargement of'Fig. 2 except illus- 45 trating the automatically operated moving elements of the fuel injecting unit in their full open position of travel.

Fig. 6 is a diagrammatic sketch illustrating one of the fuel atomizing and injectingunits as it 55 would appear if mountedin a marine or automobile type of internal combustion oil fuel engine, and further illustrates the general arrangement of the auxiliary equipment of such unit. 55

minute cylindridally shaped elongated fuel in- In the accompanying drawing, similar numerals and letters represent and indicate similar parts in the several views, the numeral I indi- .typepf internal (fontbustion oil fuel engine) may lower end, with a suitable gnQ-imhfsimilfih to that of the ay. nspark plug) which may be apted to sec re said" "unit, the engine cylcsothatgitfs'extreme lower end will be consaggy exposedftd'. the variable pressures and temperatures withinthe-combustion chamber 3a of such engineil w lliach of said units l or Ia consists of a differential area actuating piston l which is. adapted to fit snugly-to and recipro c within af cylindrically, shaped chamber Ia normally-seat withfits lb in contact th the conically shaped-seatAc (the latter beingfjlocated in the1-lower portion .2, of theor Ia,' adjoining the"combustion chamber sl n -wh ts a ,c indri ally shaped proj ct n reducedltip portion 4d adjoining the lower end of: said discfib'and-adaptedto be constantly exposed to said'ckimbust'ion chamber and to be appreciably smaller than and -thusto fit within the cylindricallyshaped' thrbatf opening I?) of said body, portlon.2;-said"piston 4 having an y shaped internal. seat portion extends. downward from the id piston) and terminates'at has end id its lower ngin a minute cylindrically shaped orifice 4) which latter in turn terminates at its lower end in 'a"c,onically shaped nozzle 40 which "latter extends thrf llgh tip Id.

The elongated, cylindrically shaped fuel atomizing and injecting piston valve! is adapted to fit snugly a'ngiireciprocate within the cylinuriclan 'isn eai chamber at which latter is 10- sated inthe' intermediate bodyportion 6 of the unit I or Ia) and-is equipped at its extreme lower end with an elongated conically shaped valve disc 5d (corresponding with and adapted to seat against seat'lel having in the intermediate portionthereof a minute annular shaped fuel atomizing groove is which latter is connected to the jection chamber (which latter extends lengthwise through-out the greater portion of and internal to valvei) by and through the fuel diffuser ports 5 (which latter extend radially through said valve -5), and in its upper portion with a suitable. radially extending fuel supply port 5h (which latter intermittently offers communication between the annular shaped fuel sup- I be and the. fuelginjection chamber matic air supply chamber Ia (located in the upperend of 8) and the chamber 4a (and terminating at a predetermined location in the wall of the latter) is the pneumatic air communication port 1b which latter is adapted to intermittently '(being controlled by the movement of piston 4 in to) form communication between said chambers.

In the upper end of fuel supply chamber 51' and extending through body portion 6 to the outside atmosphere is the air vent port 2112 which latter is equipped with a regulating needle valve 5| which is for the purpose of venting off any quantity of air that might collect in chambers 59 or 51 under adverse operating conditions.

Extending down into and adapted to fit snugly within the fuel injection chamber 59 (of the valve 5) is the fuel injection plunger 8 which latter (due to movement of the piston valve 5 as will beexplained later) is adapted to intermittently pass beyond port 5h (in chamber 5a) and thus to cut-off communication (through said port 5h) between chambers 5g and Si and thereby to trap (at such times) the fuel in the former chamber.

Inthe mechanicallyv regulated fuel atomizin and injecting unit I, the fuel injection plunger 8 is rigidly secured (at its upper end) within the regulating spindle 9 which latter is rotatably mounted within the upper body portion II) of the unit I and is equipped, at its lower end, with an enlarged, hollow, externally multiple right threaded portion 9a (which latter is adapted to be telescoped internally by the piston valve 5 and to fit snugly externally within a suitable threaded portion in body I0) and, at its upper end, with a cylindrically shaped journal portion 9b (which latter extends upward through a suitable stufilng box Illa in the body I0 and projects above the upper end of thelatter) the projecting portion of 9b having clamped thereto, by the bolt 9c, the crank arm 9d which latter has pinned to the opposite end thereof, with the pin Fig. 6); when several units I are to be coupled together with the coupling strip Si (in a multicylindered engine), the individual units I may be adjusted while the engine is operating by loosening clamp bolt 90 and rotating 9b clockwise to increase the amount of fuel injection and vice versa, and after such individual adjustments are made, .the series of units I may be regulated collectively through movement of said strip 8! clockwise (Fig. 1) to increase the fuel injection of all the cylinders of the engine and vice versa.

In the hydraulically regulated fuel atomizing and injecting unit Ia, the fuel injection plunger 8 is adjustably secured (being threaded at its upper end) Within the hydraulically operated plunger II which latter is reciprocatably mounted within the upper body portion I2 of the unit la and is equipped, at its lower end, with an enlarged flanged portion Ila (which latter is adapted to bear against the resilient spring IIb) and, at its upper end, with a packed plunger portion which is a snug fit within the cylindrically shaped chamber I I] and consists of a pair of opposed leather packing cups No, a collar IId (which the latter is located between said cups) and a retainer washer I I6 which latter is located above the upper of said cups and secures them to said plunger portion. The upper end of said cylinder II] is connected with the master hydraulic cylinder II? by and through the fitting IIh (the latter having the minute restriction orifice I lg at its lower end), and the tubing connections H2"; and said master cylinder II is operatable by the manually operated foot pedal Ilk. When several units la are to be regulated together simultaneously, each individual unit la (of such units) is adjusted separately by adjusting the combined fuel metering and injection plunger 8 in plunger II, and then regulating all of said units Ia collectively and simultaneously by and through movement of the plunger of said master hydraulic cylinder in to increase and out to decrease the quantity of fuel injection of said units. Any supply of fluid into chamber II from I I9 will tend to close spring IIb and will force plunger and 8 to a lower level in cylinder III and fuel injection chamber 59 respectively and vice versa and will increase or decrease respectively the quantity of fuel injection of all units, likewise connected with My, simultaneously. I

It is understood and is obvious that the connecting regulating strip 9 of the unit I, or the plunger of the hydraulic cylinder IIa' of the reg-- ulating system of unit Ia, could be connected to a common ball or other type governor in place of the manually operated foot pedals previously mentioned.

Fig. 6 is a diagrammatic illustration of one of the, units I mounted so as to have its lower end projecting into the combustion chamber in of the cylinder of the internal combustion engine 3, its intermediate body portion 6 connected with the fuel tank I6 through the pneumatic air tubing and connections I4 and the fuel supply tubing and connections I5, and its regulating crank arm 9d connectedwith themanually operated foot pedal 99 through the multiple connection regulating strip M and the linkage illustrated diagrammatically. The pneumatic air tubing I4 and fuel tubing I5 are both secured to the unit I by the bolt I3 and securing dog lid, and have therebetween and the fuel tank I6, the pneumatic air cut-out valve I41: and fuel cut-out valve I5a (and also suitable air and fuel strainers, not illustrated). the former mentioned tubing extending inside of and to the'top of said tank and the latter inside of and to the bottom of said tank. The top of said tank I8 having secured thereto and in communication with the inner portion thereof the adjustable relief valve I! (which latter is normally set at 100 pounds pressure per square inch), and also the filler cap I! which latter has secured thereto the outside source pneumatic air supply valve connection Ila.

As the units I and la function alike, except for their differences in remote means of regulation,

. I will endeavor to describe the construction and operation of one of the units I, and for convenience of such description will assume that the moving elements of said unit are in the la and 4a and in the communication passage 1b connecting them, and that said unit I is mounted, as illustrated in Fig. 6, in the engine 3. We will now further assume that we want fuel atomization and injection to start automatically when the pressure of the compressed air in combustion chamber 3a (compressed therein during the compression cycle of said engine) exceeds 400 pounds per square inch, that the threaded portion 2a of the unit I is the same size as a common inch spark plug, and that the other dimensions of said unit are of proportionate size therewith. We will then construct the unit I so that the cross-sectional area across the throat 2b-i-is .025 of a square inch (known as area (A)), the crosssectional area of the upper diameter of chamber 4a four times as large as area (A) or .1 of a square inch (known as area (B)), the crosssectional area of the lower diameter of said chamber 4a (known as area the same as area (B); therefore 100 pounds pneumatic air pressure exerted against the upper ends of 4 and (equal to area (B)) would prevent 400 pounds pneumatic air pressure in combustion chamber 3a and exerting itself against area (A) under.

trated in Fig. 3. During the first part of such movement of 4 and as the disc 4b of the latter leaves its seat 40, the pneumatic air in combustion chamber 3a rushes .into the chamber 4a (area(C)) beneath piston 4 and instantly accelerates the upward movement of the latter in chamber 4a, and as the upper edge of piston 4 passes beyond the communication port lb (in the wall of chamber 4a) the pneumatic air above piston 4 (at approximately 100 pounds pressure) is trapped in the annular shaped chamber 10 (above piston 4 and surrounding the intermediate portion of piston valve 5 Fig. 5) and is compressed therein (by said upward movement of 4) to a pressure appreciably higher than the actuating pressure in combustion chamber 3a and exerting itself against the under side of 4 (area (Cl). This relatively high pneumatic air pressure generated in chamber 1c is the result principally of the relation of various cross-sectional areas of the unit I to oneanother, and also to the accelerated upward movement (ram like) of piston 4 as previously described. We will assume that the cross-sectional area of the diameter of portion 57' (of 5) is .05 of a square inch (known as area (D) then area (B) minus area (D) (known as area (B--D)) is likewise .05 of a square inch, and as the pneumatic air pressure above the upper end of 5 is (constantly) 100 pounds we have: .05 100 equals 5 pounds previously mentioned). However, itis not desirable to generate 700 pounds per square inch pneumatic air pressure in chamebr 10 (prior to commencement of combustion) so therefor, some means must bedevised to release such pneumatic air from chamber 'lc into chamber 3a at some pre-determined pressure ranging between 700 and 400 pounds per square inch, and some means-must also be devised for separating the disc d (of 5) from its seat 4e (of 4). This release of said pneumatic air from and separating of 5d and 4e is accomplished as follows; we will assume that .we want to release said pneumatic air from chamber 1c when it exceeds 500 pounds per square inch, then resorting to calculation of areas we have; as previously mentioned the down pressure on area (D) equals. 5 pounds, therefor, the latter divided by 500 pounds equals .01, which latter is the correct fractional part of a square inc-h area (known as area (E)) necessary to separate 5d and 5e under such pressure conditions and the difference of area (D) minus area (E) or .05 minus .01 equals .04 (known as area (D-E)) which then will be the crosssectional area in square inches of diameter 5k or the largest diameter of disc 5d of 5. As the piston 4 travels upward in'chamber 4a and nears the position of travel in which it is illustrated in Fig. 5, the pneumatic air pressure in chamber 1c slightly exceeds 500 pounds and as described above separates 5d from 4e and at approximately the same instant the lower edge of fuel supply port 5h passes upwardbeyond the lower edge of fuel injection plunger 8 and thus cuts off communication between fuel supply chamber 5i and fuel injection chamber 59. As the piston 4 and piston valve 5 continue on their upward travel. the fuel injection plunger 8 displaces aminute quantity of oil fuel from chamber 5g viavthe radial defuser holes 5f into the annular shaped fuel atomizing groove 5e and thence into the minute separating space (between disc 5d and seat 4e as previously described) wherein it is picked up by the relatively high pressure pneu- 'matic air (which latter is being ejected from chamber 1c via said space into chamber 3a) and is minutely atomized and carried with said air via said space thence the minute orifice 4! and thence the tapering nozzle 4g into said combustion chamber in an extremely fine mist status and thoroughly conditioned and prepared to 1 become ignited instantly by and through contact with the high temperature of the relatively highly compressed combustion air charge in said combustion chamber. The length of duration of said fuel injection in degrees of rotation travel of the engine crank-shaft depending principally upon the size of the minute orifice 4f, the adjustment position of the fuel injection plunger as to the quantity of fuel being injected, the volume of pneumatic air ejected from 10 to 3a via said minute orifice U, and other minor details. The period of fuel injection normally continuing from approximately 7 degrees in advanceof top dead center to approximately degrees past such dead center.

After 5d is separated from 4e, and the lower edge of port 5h passes upward beyond lower edge of plunger 8, the disc 51) of -5 contacts its seat 5c in B and stops the further upward travel of piston valve 5; this stopping of 5 discontinues further displacement of fuel from So by plunger 8 and as the piston 4 closes in the space separating 5d and 4e the relatively high pressure pneumatic air continues to escape through said valve H.

space until 4e contacts 5d and thus blows said space clear of 5 oil fuel and prevents dribbling at orifice 4 and nozzle 4g.

Due to the acceleration of the piston 4 in its upward travel (as previously described) and to the distance the piston valve 5 travels before port 5h passes beyond the end of plunger 8. said piston and piston valve gain considerable velocity before injection starts and the delivery of such injection is after a ram fashion which tends to further break up said oil fuel into a mist and this method of fuel automization and injection wil lead the way to burning crude oil for fuel in all oil fueled engines.

The clearance space in chamber 'lc wlth'piston 4 and piston valve 5 at the upper ends of their travel as in Fig. 3 should be kept to a minimum.

Compressed air is supplied to fuel tank l6 by and through slight leakage of either highly compressed air or combustion gas'from combustion chamber 3a through chamber 4a (as diagrammatically illustrated in Fig. 3) through the small clearance space between piston 4 and the walls of its cylinder 4a and into the pneumatic air communication port 112 and thence'via chamber Ia and tubing and fittings H to said fuel tank; any slight surplus amount of such compressed air being released out of said tank through relief It being obvious that such relief valve could be set at a higher pressure than 100 pounds per square inch and that a manually operated pressure regulating means could be interposed between such units I or Ia and tank I6 to regulate such pneumatic air to various pressures below the setting of such relief valve and thus to furnish a means of varying the timing of the fuel injection in relation to the travel of the moving elements of the engine; a release or reduction in such pressure advancing the timing of said fuel injection and vice versa, and an abnormally high pressure stopping said engine.

As the pressure in the combustion chamber 3a drops during the exhaust cycle period of operation of said engine 3, the piston 4 and piston valve recede in their respective cylinders as such pressure bears relation to the pneumatic pressure above said piston and piston valve tending to force them downward, and as they near the bottom end of their travel the closeness of the fit of of the tip 4d to the throat opening 2b causes a certain quantity of the expended gas escaping from cylinder 4a beneath piston disc 4b become trapped in said cylinder and to become compressed by such piston in said cylinder and thus to cushion the aforesaid piston and piston valve at the lower-end of their downward travel. During such cushioning of said piston and piston valve a part of said compressed gas beneath said piston is displaced into the annular shaped cushion compression chamber 4h and assists in preventing pneumatic air leakage from chamber 4a and "la to combustion chamber 3a by forming a pressure seal therebetween during the period said piston and said piston valve are at rest in their normal closed position of travel intermittent their stroke periods of operation. Likewise during the upward period of travel of said piston and piston valve members and as they near the outward end of their stroke travel they are cushioned by and through the closeness of the fit of the outside diameter of the disc 5b (of 5) to the wall of the cylinder 4a and the allowed clearancespace therebetween for the escape of the pneumatic air being displaced above disc b into the compression space beneath said disc and above piston 4.

It is understood that in certain cases where trouble may be experienced (due to air leakage into the fuel supply chamber 52') that the air vented from 5i through port 2m and needlevalve 5| to the atmosphere could be lead through a suitable tubing connected with said valve (not illustrated) to a suitable small vent drain tank and a very small leak-off allowed to continue through said valve and drain connection into such tank. a

The invention herein described may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment to me of any royalty thereon or therefor.

Having fully described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A fuel injection device for an oil engine comprising an elongated cylindrically shaped actuating piston member adapted to be fioatably mounted adjacent the combustion chamber of such engine, a tapering seat located within said actuating piston member and terminating towards said combustion chamber in a minute cylindrical orifice, a tapering nozzle adjacent the combustion chamber end of said minute orifice, an elongated cylindrically shaped piston valve member of smaller diameter than and floatably mounted adjacent to said actuating piston member, a tapering disc integral with said piston valve member and corresponding to and fitting within said tapering seat, an elastic substance compression space adjacent the larger end of said tapering. seat anddisc, an annular shaped groove located in the periphery of the intermediate length of said tapering disc, a cylindrical fuel chamber located concentrically within said piston valve member and in constant communi-- cation with said annular shaped groove, a fuel supply port extending radially through said piston valve member into said fuel chamber, a fuel injection plunger member slidably extending into one end of said fuel chamber to adjacent said fuel supply port, an elastic substance supply space located adjacent the end of said piston valve member opposite the tapering disc end of the latter, means, for remotely controlling the location of said fuel injection plunger member relative to said fuel supply port, means for supplying liquid fuel under a slight pressure to said fuel supply port, means for supplying an elastic substance under a slight pressure to said elastic substance supply and compression spaces, means for actuating said actuating piston and piston valve member, means for compressing said elastic substance in said elastic substance compression space, means for separating said tapering disc and said tapering seat at a predetermined point in the travel of said actuating piston member, and means for displacing the compressed elastic substance from said elastic substance compression space and the liquid fuel from said fuel chamber and uniting and injecting them into said combustion chamber of such engine.

2. In a fuel injection device for an oil engine the combination of an elongated cylindrically shaped actuating piston member adapted to be floatably mounted adjacent the combustion chamber of such engine, a tapering seat located within said actuating piston member and terminating towards said combustion chamber in a a minute orifice, an elastic substance compression space adjacent the end of said actuating piston member at the larger end of said tapering seat, an elongated cylindrically shaped piston valve member of smaller diameter than and floatably mounted adjacent to said actuating piston member, a tapering disc integral with said piston valve member and corresponding to and fitting within said tapering seat, an annular shaped groove located in the periphery of the intermediate length of said tapering disc, a cylindrically shaped fuel chamber located'concentrically within said piston valve member and in constant com-

Images