US3543735A

US3543735A - Combustion system for internal combustion engine

Info

Publication number: US3543735A
Application number: US739434A
Authority: US
Inventors: Perry Lester Kruckenberg; Harold Elden Anderson; Ray Lavette Carlson
Original assignee: Mcculloch Corp
Current assignee: Mcculloch Corp
Priority date: 1968-06-24
Filing date: 1968-06-24
Publication date: 1970-12-01
Anticipated expiration: 1987-12-01
Also published as: FR2011589A1; BE734769A; DE6912261U; DE1915531C3; GB1227641A; DE1915531B2; DE1915531A1

Description

United States Patent un 3,543,735

[72] lnventors Perry Lester Kruckenberg 1,955,056 4/1934 Dolan 123/32 LosAngeles; 1,981,874 11/1934 Mock 123/32 Harold Elden Anderson, Lomlta; Ray 2,250,364 7/1941 Fiedler 123/32 Lavette Carlson, Rolling .Hills, California 2,363,131 1959 D0118 1 /32 [21] Appl. No. 739,434 2,914,044 11/1959 Liebel 123/32 [22] Filed .Iuue24, 1968 3,125,080 3/1964 Hottmann 123/32 [45] Patented Dec. 1, 1970 3,386,422 6/1968 Eyzat 123/32 [73] Assignee McCulloch Corporation 2,107,792 2/1938 lluesby. 123/32 L08 Angeles, California 2,561,628 7/1951 Kogel 123/32 a corporation of Wisconsin OTHER REFERENCES [54] COMBUSTION SYSTEM FOR INTERNAL 7 Automotive lndustriesJune I5. 1956. pp. 66. 67. 132. 133. 136, 140.

Primary Examiner-Laurence M. Goodridge Anorney- Burns, Doane, Benedict, Swecker & Mathis ABSTRACT: Method and apparatus for burning fuel within the cylinder of an internal combustion engine wherein a series of spaced and mutually distinct airstreams are projected into the interior of a combustion zone of the cylinder. Another series of spaced and mutually distinct streams of fuel are projected into the combustion zone, with at least some of the fuel streams individually intersecting airstreams. The passage of the fuel streams into the airstreams is peripherally confined to define a series of mutually distinct fuel and airstream intersection zones where the fuel is effectively dispersed and heated. These intersection zones define burning loci.

Patented Dec. 1, 1970 Sheet 1 of 3 PERRY LESTER KRUCKENBERG HAROLD ELDEN ANDERSON RAY LAVETTE CARLSON Patented Dec. 1, 1970 7 3,543,735

Sheet g or 3 A E a g it 5 o S w 800 f 5 a: Z 3 N E a 3 e E v 8 Z i a; 5 5 400 Y' g E 2 E .JE LQEQBE E i INCREMENT g a He 9 TEN DEGREE INCREMENTS 0F CRANKSHAFT ROTATION E A 3 g E .35 E A LT H E2 3; 3 .30 o E o-' E g .25 o a 2 T 40 so so 70 so 90 :00 no I20 FIG '0 momma MEAN EFFECTIVE CYLINDER PRESSURE (PSI) PISTON TOP DEAD CENTER INVENTORS PERRY LESTER KRUCKENBERG HARO ELDEN ANDERSON RAY ETTE CARLSON BY W ATTQRNEYS Patentd Dec, 1, 1910 3,543,735

Sheet of 3 I l COMBUSTION SYSTEM FOR INTERNAL COMBUSTION ENGINE GENERAL BACKGROUND, OBJECTS AND SUMMARY OF INVENTION The internal combustion engine art has evolved continuously toward the. goal of producing more efficient combustion, quieter engines, lower exhaust temperatures, improved ease of starting, and the ability to handle a wide range of fuel characteristics. I

These optimum goals notwithstanding, and in spite of an almost endless variety of structural arrangements designed hopefully to attain these improvements, the ultimate goals, by and large, have remained elusive.

In recognition of the need for a fresh approach directed to the attainment of these goals, it is an object of the invention to provide improved apparatus and methods for burning fuel in internal combustion engines, which apparatus and methods promote more even combustion so as to improve the efficiency of, and control over, fuel burning, improve ease of engine starting, and facilitate the ability of enginesto accommodate diverse fuels.

It is a related object of the invention to provide such methods and apparatus which, in producing more even burning, minimize or eliminate detonation tendencies so as to maintain lower peak pressures within the combustion zone, thereby reducing the possibility of mechanical damage, lowering the level of engine noise, and lessening the need for heavy engine frame structures.

It is a particular object of the invention to provide a uniquely effective system for utilizing air, which has been compressed and heated by a piston, to disperse and heat fuel being injected into a combustion chamber during the downstroke of the piston.

A further object of the invention is to provide an improved system for dispersing and burning fuel in the'cylinder of an internal combustion engine so as to substantially reduce carbonization and thereby lower the operating temperature of the engine and the engine exhaust.

In achieving at least some of these objects, there is presented through the invention a method of burning fuel within the cylinder of an internal combustion engine, which method involves the projection of a series of spaced and mutually distinct airstreams into the interior of a combustion zone of the cylinder of an engine. Another series of spaced and mutually distinct streams of fuel is projected into the combustion zone. At least some of the fuel streams pass through at least some of the airstreams. The passage of the fuel streams into the airstreams is peripherally Confined so as to define a series of spaced and mutually distinct fuel stream and airstream intersection zones. 7

ln a preferred embodiment the air and fuel streams entering each peripherally confined intersection zone pass in generally countercurrent turbulent flow relationship, thereby tending to shear and disperse fuel particles.

The dispersion of the fuel in the intersection zones, and the preparation of the fuel for burning in the zones, is enhanced by heating the air of the streams which are projected into the intersection zones. This heating is effected by the compressive action of a piston reciprocably mounted within the cylinder prior to the generation of the airstreams.

Other independently significant facets of the invention entail apparatus means operable to accomplish the abovedescribed combustion techniques.

A particularly significant apparatus of the invention resides in the specific structure of a piston protrusion which cooperates and is telescopingly received within a combustion zone formed in the cylinder head of an internal combustion engine. The protrusion includes a slotted annular rim encircling a semitoroidal face. The combustion zone includes a cylindrical wall and a second semitoroidal face disposed so as to face the semitoroidal face of the protrusion. A nozzle is mounted in the combustion zone and is operable to direct streams of fuel into the rim slots of the protrusion.

DRAWINGS In describing the inventi'omreference will be made to a preferred embodiment shown in the appended drawings.

In the drawings:

FIG. ll provides a vertically sectioned, schematic view of a preferred form of the internal combustion engine of the present invention illustrating basic relationships between a combustion or working cylinder and an air pumping cylinder;

' FIG. 2 provides an enlarged, vertically sectioned view of a piston protrusion and cylinder head combustion zone of the FIG. 1 assembly, illustrating the protrusion as it is about to enter the combustion zone;

FIG. 3 illustrates the protrusion received within the combustion zone and moving upwardly;

FIG. 4 provides a partially sectioned, perspective view of the projection and combustion zone as they are disposed while fuel is being injected into the combustion zone by a fuel injection nozzle;

FIG. 5 provides a vertically sectioned, fragmentary view of the protrusion at the point where it commences to withdraw axially out of the combustion zone;

FIG. 6 provides a transverse sectional view of the protrusion and combustion zone as. viewed along the section line 66 of FIG. 3;

FIG. 7 provides an enlarged, elevational view of the protrusion of the FIG. 1 combustion cylinder, illustrating this protrusion separated from the piston upon which it is mounted for In accomplishing many of the major objects heretofore delineated, the invention may also be viewed as a technique for burning fuel in the combustion zone of the cylinder of an engine wherein a plurality of spaced combustion pockets are defined within the cylinder, with each of the pockets communicating with a combustion zone located in the cylinder head of the engine.

Fuel and air are confined,'rnixed and agitated in each of the spaced pockets; The fuel is burned in the spaced pockets and products of combustion are discharged from the spaced pockets into an expansible chamber communicating within a reciprocable piston mounted within the cylinder.

operational purposes;

FIG. d provides a top plan view of the protrusion shown in FIG. 7;

FIG. 9 provides a graphical representation of the pressure within the combustion cylinderof the FIG. 1 assembly in relation to crankshaft position and the operating condition of the fuel injection nozzle; FIG. 10 provides a graphical representation of the operating characteristics of a diesel engine fabricated and operated in accordance with the present invention; and

FIG. 11 illustrates, in a rotary graph format, the position of the working piston driving crankshaft of the FIG. 1 engine during various phases ofa single cycle.

OVERALL STRUCTURE necting rod 7 joumaled on a crankshaft 8 is connected by a wrist pin 9 to piston 5. Another connecting rod 10 journaled on crankshaft 8 is connected by a wrist pin 11 to piston 6. Viewing the engine 1 as shown in FIG. 1, crankshaft 8 rotates in a clockwise direction.

One or more air inlet ports 13 in cylinderwall 3 provide communication with a source of air. An outlet port 14 provides communication between the cylinder interior zone 12 and a conduit 15. Conduit 15 serves to feed airto air inlet ports to formed in the side wall of cylinder 4. An exhaust port 37 is formed in cylinder wall 4 and serves to discharge products of combustion.

Crank arms 7 and 10 are both journaled on crankshaft portion 8a, which is off center from the axis 812 of crankshaft rotation. With the illustrated right angled relationship between cylinders 3 and 4, pistons 5 and 6 will operate 90 out of phase. Thus piston 5 will uncover ports 15, allow air to enter zone 12, and again cover ports 13 while piston 6 is moving 'on a down stroke.

During the first part of the downward movement of piston 6, after piston 5 has moved down to uncover ports 13, and while air is entering the zone 12 by way of the uncovered ports 13, the ports 16 will be closed by piston 6. Ports 16 will remain closed during an intermediate part of the down stroke of piston 6 while piston 5 is commencing to move up. During the terminal part of the down stroke of piston 6 and the initial part of the up stroke of this piston, piston 5 will be moving upwardly, with ports 13 uncovered, and transfer air from chamber 12 through conduit 15, to zone 18. This transfer will result from piston 6 clearing or uncovering the air inlet ports 16. After this air has been transferred to zone 18, and ports 16 have been closed by the upwardly moving piston 6, it will becompressed and heated for ignition purposes as a result of continued upward movement of piston 6.

FIG. 1 illustrates working cylinder 4 with conventional liquid cooling passages W. in a conventional fashion, cooling fluid may be circulated through the passage means 19 so as to maintain the temperature of the cylinder 4 within acceptable limits.

A conventional fuel pump 26 is mounted on engine 1. Pump 20 may be operated, for example, by a conventional cam mechanism associated with a crankshaft 8. This fuel pump 20 serves to supply liquid fuel, such as light oil, to a fuel injection nozzle 2i. Fuel injection nozzle 21 discharges this fuel in the form of spaced sprays into a combustion zone 22 located in the cylinder head 23 of working cylinder 4. The crankshaft controlled fuel pump 20 serves to start and stop the injection of fuel into zone 22 in accordance with a cyclic injection pattern to be hereinafter described in greater detail.

The manner in which combustion is effected within the cylinder 4 is uniquely controlled by the combustion zone 22 and a protrusion 24 mounted on the working face or fluid reaction face of piston 6.

COMBUSTION CONTROL BY COMBUSTION ZONE AND PISTON TROTRUSION Combustion zone 22, as shown in FIGS. 2 THROUGH 6, comprises a cylindrical wall 25 projecting coaxially of the axis of reciprocation of the piston 6 and the central axis of the cylinder 4. Cylindrical wall 25 intersects a generally annular and planar cylinder head surface 26. This surface 26 extends radially of the axis of reciprocation of the piston 6, away from the junction where the cylinder wall 25 intersects the working zone 18.

A semitoroidal surface 27 is coaxially alined with the axis of reciprocation of the piston 6 and merges tangentially at its annular periphery with the cylindrical wall 25. As illustrated, the extremity 28 of fuel injection nozzle 21 defines a portion of surface 2'7 and provides the central peak" portion of this semitoroidal surface 27.

The piston protrusion 24 comprises an annular rim 29 which is coaxially alinedwith the axis of reciprocation of the piston 6. A second, semitoroidal surface 36 is carried by the protrusion 24 in coaxial relationship with the piston axis of reciprocation. Surface 30 is disposed in mirror image relationship with, and faces, the surface 27.

As illustrated, this second, semitoroidal surface 30 is defined by a circular axis of cross-sectional curvature 31. This axis of curvature extends in a plane passing radially of the axis of piston reciprocation, and through the pointed tip portion 32 of the surface 30. Thus, the radius of curvature 33 of the lefthand side of the cross section of surface 30, as shown in FIG. 2, is exactly the same as the radius of curvature 34% of the righthand surface. These two radii 33 and 34, when alined radially of the piston axis of reciprocation, terminate at the surface point 32.

With the mirror image reiationship existing between these surfaces 27 and 3f), the radii of curvature 3.5 and 36 of the left and right-hand sides, respectively, of surface 27 are mutually equal and equal to the radii 333 and d4.

Radii

35 and 36 terminate substantially in contiguous relationship with the cylindrical wall 25, where this wall 25 tangentially merges with surface 27.

When piston 6 is disposed at the extremity of its compression stroke as shown in FIG. 5, a slight axial gap 37 will exist between the annular surface 26 and an annular piston surface 38. Surface 38 comprises an annular fluid reaction surface on the working end of piston 6. Surface 38 projects radially away from the protrusion 24. With piston 6 thus disposed at its compression travel extremity, the circular axis of curvature 31 of surface 30 becomes coextensive with the circular axis of curvature 39 of the cylinder head toroidal surface 27, as generally shown in FIG. 5. At this point, the illustrated radii 33, 34 35 and 36 become axially alined, i.e. coplanar.

A series of peripheral slots 46 are formed in the outer periphery of rim 29. The cylindrical outer periphery 41 of rim 29, interrupted by the slots 40, is telescopingly received within the cylindrical wall 25 in a noninterfering fit relationship. The somewhat exaggerated radial clearance 4E2, shown in the drawings as existing between the rim periphery 4i and the cyliiidrical wall 25, provides for this noninterfering fit relationship and ensures that the protrusion 2a is freely reciprocable within the wall 25. Each slot includes a planar inner wall 13 which extends parallel to the axis of reciprocation of piston 6 and perpendicular to a radius extending from this axis. The radially outermost side 44 of each slot 40 is open, as shown in FIG. 6.

As illustrated in FIGS. 4 and 6, the circumferentially-spaced sides of this slot ill are defined by a pair of mutually parallel, planar, sidewalls 45 and i6.

sidewalls

45 and 46 are parallel to the radius which is perpendicular to the slot base 43 and which extends from the piston axis of reciprocation 47. This radius intersects each surface 43 circumferentially midway between the slot sides 46 and 45 and axially midway between the slot top edge i8 and the slot base wall lower edge 49.

The slots 40 are symmetrically disposed about the periphery of rim 29, i.e. are evenly circumferentially spaced. in the preferred and illustrated embodiment six slots are provided. However, the number of slots may vary depending upon engine requirements.

The top edge 48 of the slot base wall 43 is sharp or knifelike in character, owing to the fact that it is defined by the intersection of planar surface 43 and planar surface 30. The top edge 50 of slot sidewall 36 and the top edge Si of slot edge sidewall 45 are also sharp or knifelike, resulting from the planar intersections of

surfaces

46 and 45 respectively, with the interrupted annular surface 52 which defines the top of rim 29 and which extends generally radially of the axis of reciprocation of the piston 6,

Thus, the slots 40 provide airstream defining orifices circumferentially spaced about the periphery of the protrusion 24. Each such orifice extends generally longitudinally of, i.e. parallel with, the axis 47 of piston reciprocation and is inclined relative to the axis of reciprocation in a direction extending circumferentially about the combustion zone 22.

Protrusion 24 is secured to piston head wall 53 by a mounting stud 5'4. Mounting stud 54 projects axially through a central aperture 55 formed in piston head wall 53. A threaded nut 56 threadedly engages the threaded lower end 57 of the stud 54. Nut 56, acting through

washers

58a and 58b, serves to elastically anchor the protrusion 24 to the head wall 53 by engaging a series of Bellville spring washers 59. This resilient anchoring arrangement tends to ensure that the protrusion 24 does not become separated from the piston head wall 53 during engine operation. If desired, anchoring pin 60, schematically shown in FIG. 2, may serve to fixedly secure the nut 56 on the threaded study portion 57. Pin 6% transversely intersect threaded stud 57 and nut 56, after these components have been assembled, so as to prevent rotation of the nut 56 which would tend to remove it from the stud end 57.

As will be appreciated, this mode of mounting the protrusion 24 requires minimum" alteration of the conventional structure of the structure of the piston 6.

The terminus 28 of nozzle 21 is provided with a series of circumferentially spaced, fuel spray or jet defining nozzlelike orifices 61. The nozzles or orifices 6i are oriented so as to project a series of six fuel sprays 62 projecting into the com bustion zone 22. These fuel sprays 62 are mutually distinct and circumferentially spaced from each other. The sprays 62 are more or less alined with a conical plane diverging downwardly from the tip23 and intersecting all of the slots or flow paths 40. This surface ofalinement of the spray 62 intersects open ends or mouth 63 of the slots l throughout the period of time that the slot-carrying rim 29 is reciprocating withing the cylindrical wall 25. This alinement of the sprays results from having the conical alinement surface generallyintersect the circular junction of intersection 64 between the

surfaces

25 and 26. In actual practice, the sprays 62 have been directed toward points 64a, located about one-eighth of an inch above the plane of junction 64. The radial width 65 of each orifice 410 is such as to ensure that each spray 62 will continue to enter a slot mouth 63, even when the protrusion 24 has been reciprocated to the extremity position shown in FIG. 5.

At this point, it will be appreciated that when piston 6 nears the upper portion of its reciprocation, so as to cause the rim extremity 52 to be alined with the cylinder head surface 26, the slots or orifices 40 substantially control fluid communication between the cylinder working zone 18 and, the combustion zone 22 formed in cylinder head 23. This fluid communication control, afforded by the slots 40, continues as the piston 6 continues its reciprocation so as to move the protrusion 24 to the ultimate position shown in H6. 5. This control further continues during the withdrawal or downstroke of the piston 6, until the protrusion 24 returns to the position shown in FIG. 2, i.e. the position where the upper ends 63 of the slots 40 are alined with the wall 26.

Some limited communication between the zones 18 and 22 sequence in relation to that afforded by the slots or paths 40.

DIMENSIONAL AND CYCLE CRITERIA The teachings of the invention have been applied specifically to the operation of a small diesel engine rated at horsepower. In this engine, the cylinder has a 2.75 inch diameter bore and a 3 inch stroke.

A variety of protrusions 24 have been incorporated in the piston head 53 of this engine. In general, the semitoroidal surface 30 of these protrusions have been dimensioned such that

radii

33, 34, 35 and 36 were between .310 and .315 inches. The diameter of the cylindrical peripheries of protrusions 24, as defined by a cylindrical surface 66, has generally been on the order of between 1.185 and 1.191 inches.

The axial height 67 of wall 41 of these protrusions was generally between .222 and .225 inches. The perpendicular distance between walls 45 and d6 was generally on the order of from about .240 inches to about .280 inches. The radial gap between each wall 43 and the cylindrical surface 66, which is coextensive with walls ll, was generally on the order of from about .l20 inches to about .125 inches.

The protrusions 24 were fabricated from stainless steel.

The protrusion dimensions substantially determine the dimensions of the combustion zone 22, in view of the relationships between the protrusion and the combustion zone previously described. It is contemplated however, that the radial gap 42 between the walls at and the cylindrical wall 25 may be on the order of three one-thousandth to five onethousandth of an inch.

The axial gap 35 between

surfaces

26 and 38, when the piston 6 was in its uppermost position, was generally on the order of thirty-seven one-thousandth of an inch. The gap 63 between the tip 32 and the lower extremity of the nozzle 21, when the piston was in its uppermost extremity was generally on the order of two-hundred o'ne-thousandths of an inch.

Tests on this engine were conducted with slots 40 where the slot sidewalls 45 and i6 ranged from being parallel to the axis of reciprocation of the piston 6, through angles of inclination relative to the axis of reciprocation on the order of 18, 30 and 45. Generally, six, identically oriented, peripheral slots 40 were employed for uniform evaluation purposes.

The dimensional criterial of the engine was such that the protrusion rim top surface 52 became alin'ed with the cylinder head surface 26 at a point of crankshaft rotation about 29 prior to the position of crankshaft rotation operable to bring the piston 6 to its uppermost extremity as shown in FIG. 5. This means, of course, that the protrusion 2d reciprocated with the cylindrical wall 25 for a total increment of crankshaft rotation of about 58. Throughout this total increment, the slots 40 substantially provided complete control of fluid communication between the zone 22 and the zone 18. Significantly, the zone 18, although reduced to several thcusandths of an inch in axial extent in the FIG. 5 extremity position, always remained in existence so as to provide a zone into which products of combustion could flow.

In several tests which were conducted, the fuel pump 20 was operated by timing means so as to initiate the injection of the fuel streams 62 into the zone 22 at a point of crankshaft rotation about 4 to 6 ahead of the crankshaft extremity position operable to position the piston in the FIG. 5 orientation. The orifices through which the fuel stream 62 were projected each had a diameter of about .005 inches. Observations indicate that combustion was initiated within 2 or 3 of continued rotation of the crankshaft, i.e. combustion was initiated almost simultaneously with the injection of fuel and almost at the point where the piston was at top dead center of the cylinder 4 Injection of the fuel streams 62 was generally continued for a total increment of from 12 to l5 duration after top dead center. For moderate speed engines, fuel stream injection commencing about 5 before the top dead center piston position and terminating as long as 20 after this top dead center position is believed to be beneficial. With this range of fuel injections, combustion will continue for a few degrees after the injection of the fuel streams has ceased. It is believed that this combustion will terminate prior to the exiting of the protrusion 24 from cylinder wall 25.

Thus, it is believed that with a tolerance of only a fewdegrees of crankshaft rotation, combustion was both initiated and terminated very nearly coincident with the initiation and termination of fuel injection. Further, combustion was initiated in uniquely close proximity to the top dead center piston location.

The relationships between fuel injection, fuel burning, and the position of the protrusion 24 within the cylinder wall 25 are illustrated in the crankshaft cycle diagram shown in FIG.

In FIG. ill, the shaded zone A represents the period of rotary movement of the crankshaft during which the protrusion 24 is telescoping within the cylinder wall 25. The fuel injection pattern is shown by the shaded segment B. From observation, it is believed that burning occurs within the general zone represented by the shaded segment C.

GENERAL MODE OF OPERATION OF ENGINE The general mode of operation of engine 1 will be described with reference to a single cycle, commencing with the initiation of the upstroke of the piston 6.

During the upstroke, after the ports 26 and i7 have been closed, air will be compressed and heated within the then openingly communicating zones iii and 22. Once the protrusion 24 commences to enter the cylindrical wall 25, i.e. when the surface 52 becomes'alined with the surface 26, the continued upward movement of the piston 6 will cause the air in space 18 to be further heated and compressed. This further heated and compressed airwill flow from the zone 18 radially inwardly into the open sided slots 40.

Because of the channeling influence of the slots 40, the heated and compressed air will be increased in velocity so as to flow turbulently, generally longitudinally and upwardly through the slots 10. The inclination of the slots 40 will tend to cause the airstreams, defined by the orificelike slots 40, to enter the chamber 22 and flow along the wall 25 in a generally spiral pattern. These upwardly moving airstreams will encounter the arcuate surface 27 and be deflected generally radially inwardly toward the axis of reciprocation 47 and then generally downwardly toward the arcuate surface fill.

The flow pattern of the airstrearns is somewhat uncertain, insofar as the zone between

surfaces

27 and 30 is concerned. Airstreams leaving the right side of the surface 27 may tend to initially crossover into the left side of the surface 30, viewing the surfaces in the general arrangement shown in FIG. 2. As the

surfaces

27 and 29 coverage, this crossover tendency may be somewhat minimized, i.e. airstreams deflected from the right side of the surface 27 may tend to enter the right side of the surface 30.

As the protrusion 24 nears the extremity of its upstroke, the fuel stream 62 will be projected'into the zone 22. As generally shown in FIGS. 3 and 6, each stream will be directed so as to continuously enter the slot mouths 63 while the slots 40 receiving the streams are reciprocating both into and out of the wall 25.

When the fuel streams are projected into the zone 22, ach generally downwardly flowing fuel stream 62 will encounter a generally upwardly flowing airstream in the pocketlike slot 40. The generally countercurrent flow between these air and fuel streams, coupled with the high velocity and heated character of the airstreams, will tend to produce mixing, agitation and turbulent flow in each slot 4t) operable to almost instantaneously heat and disperse the fuel of the fuel stream throughout the airstream. The peripherally confining effect of the walls d5, 33 and 46, in each slot, tends to effectively confine and thereby intensify this fuel dispersion and heating, so as to make the fuel almost instantaneously amenable to combustion.

Pursuant to the conventional mode of operation of a diesel engine, the compression induced heat will ignite the fuel. From observations, it is known that burning of the fuel is localized in the general vicinity of the slots 40. By describing burning, as occuring in the zones defined by the slots 40, it is meant that these zones, where the fuel and air intersect, provide circumferentially spaced, burning loci, with it being recognized that burning will exist beyond the confines of these slots.

It is believed that burning may be initiated somewhat above the upwardly moving orifices 40, in the general vicinity of the I fringes of the fuel streams 62. However, regardless of where burning is initiated, it is known from observations that the intersection zones or orifices 40 define spaced centers or loci of burning. In this connection it is also believed that, even though burning may be initiated somewhat above the orifices 40, the bulk of the fuel in the downwardly directed streams 62 will enter the orifices 40 for effective dispersion and heating.

In here describing the direction of flow of the fuel streams and airstreams, reference has been made to directions resulting from the illustrated posture of components in FIGS. 2 through 6. Obviously these directions would vary, depending on engine orientation.

The burning of fuel in the zones 40 continues as the piston 6 moves to the top dead center position shown in FIG. and while the protrusion 24 moves downwardly out of the zone 22 but is still retained within this zone.

The injection of fuel streams 62 terminates prior to the exiting of protrusion rim 29 from cylindrical wall 25. During the downward movement of the protrusion 24, and while fuel is being injected, air previously injected into the zone 22 and heated through combustion and compression, flows generally downwardly out of the zone 22. This air flows through the slots 40' into the annular-zone 18 which communicates with the fluid reaction surface 35 of the piston 6. it is believed that this outward flow of heated air contributes, in a particularly effective manner, to the heating and dispersion of fuel in the peripherally confined intersection zones or pockets 40.

The turbulence within the zones dill which contributes to effective mixing is believed to be augmented or improved by the lateral inclination of the slots 40 and also by the substantially right-angle turns which the downwardly flowing airstreams taken when they impinge upon the surface 3&3. That is to say, the downwardly moving airstreams move downwardly through the inclined slots ill and inpinge upon the surface 38 where they are deflected to flow radially outwardly away from the axis of reciprocation 47.

At this point, it will be recognized that turbulence is similarly generated by air flowing radially inwardly from the zone 118 through slots 40 into the zone 22 during the upstroke of the protrusion 24. During the upstroke, the air flowing from the zone 18 radially inwardly toward the axis 4'7 is deflected in a vertical plane so as to flow generally upwardly along wall 2% and is also deflected laterally because of the slot inclination. This multidirectional deflection, which occurs in a reverse sense on the piston downstroke, is believed to effectively contribute to the formation of turbulent flow in the zone f ll.

it is also believed that the airstrearns, which are deflected and somewhat dispersed by their impingement upon the

surfaces

27 and 30, provide a degree of overall turbulence which does not destroy the essential'integrity of the fuel streams 62. Nevertheless, this overall turbulence operates in conjunction with the intersection of the fuel streams 62 and the airstrcams passing through the nozzles 30 to provide an enhanced degree of fuel dispersion and heat distribution, thereby promoting overall efficiency and smoothness of burning.

It is believed that the burning of fuel coincides so closely with the fuel injection increment that burning is substantially completed prior to the time that the protrusion 24 leaves the combustion zone 22.

ADVANTAGES AND SCOPE OF INVENTION FIG. 9 graphically represents the operating characteristics of the previously described engine operating at 2200 r.p.m. Curve A in FIG. 9 represents the pressure within the cylinder 4 resulting solely from the compressive action of the piston 6. Curve B, which defines a continuation of the initial part of curve A, represents this pressure, plotted against crankshaft position, and resulting from the combustion cycle. Curve C indicatesthe position of a valve in the fuel injection mechanism which serves to control the admission of fuel to the orifices 61 for the purposes of defining the fuel streams 62.

As will be seen, the fuel controlling valve commenced to open at point D, within about 6 of the top dead center position of the crankshaft and piston. Ignition occurred at about E, i.e. within about 3 of both the top dead center position and the point where the fuel controlling valve commenced to open. The flow controlling fuel valve closed between points F and G, with valve closing commencing at point F. It is believed that the total ignition cycle terminated within the 58 increment of crankshaft rotation during which protrusion 24 reciprocated within cylindrical wall 25.

it is significant to here note that the initiation of combustion was efiected almost concurrent with the initiation of fuel injection and almost concurrent with the top dead center position of the piston.

Tests conducted with the previously described engine reflect significantly improved operating characteristics. For example, as shown in H0. ill, the indicated specific fuel consumption, at rated horsepower, was on the order of .29 pounds per horsepower per hour. This reflects unique combustion efficiency and is believed to be attributable to the particularly effective fuel mixing and combustion which occurs in the slots or zones 40.

The noise associated with this engine was substantially less than that associated with the conventional engine. Further, the exhaust temperature of the engine was observed to be between 200 and 300 F. cooler than the exhaust of a normal engine.

Engine starting characteristics were significantly improved. For example, unaided starting was able to be effected at ambient temperatures as low as F.

It was also observed that the engine will develop its rated power, under moderately heavy loads with rates of pressure rise within the cylinder on the order of p.s.i. per degree of crankshaft rotation. This is significantly below the 50 p.s.i. level where diesel knocking" noise ordinarily commences.

This lower rate of pressure rise, of course, produces a significantly lower peak combustion pressure. This lower peak combustion pressure produces significantly less strain on the engine frame and engine parts.

The turbulent flow in the zones 40, in contrast to the limited laminar flow that occurs between the

walls

41 and 25, produces such efiective fuel mixing as to significantly extend the range of fuels which may be injected into the combustion zone.

in short, the key to the invention resides in the peripherally confined fuel and air mixing and combustion zones, which zones produce such effective fuel dispersion and heating as to yield nearly instantaneous combustion, and more even and smooth burning. This enables an engine to be operated under nearly optimum conditions where fuel is injected and starts to ignite at very nearly the top dead center piston position. This also enables an operator to have almost complete control over fuel burning so as to control, effectively and predictably, the output characteristics of the engine. This effective fuel combustion substantially reduces and virtually eliminates carbonization tendencies so as to reduce the operating temperature of the engine. This tendency to reduce carbonization is desirable since carbon deposits, when formed, do not cool as rapidly as the engine structure. Thus, such carbon deposits tend, undesirably, to raise the operating temperature of the engine.

The heated air flowing out of the zone 22 through the slots 40, during the downstroke of the piston and its protrusion, is believed to contribute in a particularly effective fashion to the smoothness, evenness, and controlled nature of fuel burning. This is believed to result from the effective fuel dispersion and heating caused by the intersection of the outflowing, hot airstreams with the fuel streams discharging into the general vicinity of the orifices 40.

it is contemplated that the engine 1 may be operated most advantageously with a turbocharge form of air supply.

At this point, while it is known that the circumferentially spaced slots vastly improve engine operating conditions, it is believed that the dimensional characteristics, number, shape, and size of the slots 40 and the configuration of the combustion zones 22 and protrusion 24 may be varied to some ex tent while retaining advantages of the invention. For example, the slot surfaces 43 may comprise cylindrical segments, the overall slots 40 may comprise segments of a true helix, etc. However, it is believed, from experimental data gathered to date, that a slot inclination of about provides better results than a slot inclination of 18 or 24 or slots arranged to extend parallel to the axis 47.

It is believed that the invention is applicable to the operation spark plug ignited, gasoline engines as well as compression ignited diesel engines.

It will here be recognized that this invention constitutes a marked departure from the teachings of such prior patents as the Tartrais U.S. Pat. No. 1,450,567, the Basabe US. Pat. No. 2,658,487, the Carnner U.S. Pat. No. 2,682,862, the Froelich US. Pat. No. 2,966,145, the Held US. Pat. No. 1,696,799 and a Swiss Pat. No. 175,433 to Saurer. These patents disclose either structures which bear superficial resemblance to the present invention or structures operable to provide turbulence in the combustion end of a cylinder. However, none of these patents suggest or disclose the concepts of intersecting fuel and airstreams or the passage of high velocity, heated air through fuel streams during the initial withdrawing movement of a piston, which concepts characterize the present invention.

In describing the invention, reference has been made to preferred embodiments. However, those skilled in the com bustion art and familiar with the disclosure of these embodiments may well recognize additions, delections, substitutions or other modifications which would fall within the scope of the invention as defined within the appended claims.

We claim:

1. A method of burning fuel within the cylinder of an inter nal combustion engine housing a reciprocable piston, said method comprising:

defining, by means of wall means carried by and movable with said reciprocable piston, a series of spaced airstreams flowing between the interior and exterior of a combustion zone of said cylinder; defining a series of spaced streams of fuel projecting into said combustion zone with at least some of said fuel streams passing through at least some of said airstreams;

the passage of said fuel streams through said airstreams defining a series of spaced and mutually distinct fuel stream and airstrcam intersection zones; burning at least some of said fuel in said spaced and mutually distinct intersection zones in the form of spaced burning loci while concurrently projecting fuel from said fuel streams thereinto; and

moving said wall means which define said airstreams generally away from a source of said fuel streams while fuel is being projected into said burning loci and while said wall means provide paths of limited communication between said combustion zone and said exterior of said combustion zone, which exterior comprises a working zone of said engine in direct communication with said reciprocable piston.

2. A method of burning fuel within the cylinder of an internal combustion engine housing a reciprocable piston, said method comprising:

defining, by means of wall means carried by and movable with said reciprocable piston, a series of spaced and mutually distinct airstreams flowing between the interior and exterior of a combustion zone of said cylinder; defining a series of spaced streams of fuel projecting into said combustion zone with at least some of said fuel streams passing individually through at least some of said airstreams;

the passage of said fuel streams through said airstreams defining a series of spaced and mutually distinct fuel stream and airstrearn intersection zones; directing at least one air and at least one fuel stream entering each intersection zone through generally turbulent flow patterns tending to shear and disperse fuel particles of said one fuel stream through said one airstream;

burning at least some of said fuel in said spaced and mu tually distinct intersection zones in the form of spaced burning loci while concurrently projecting fuel from said fuel streams thereinto; and

3. A method of burning fuel within the cylinder of an internal combustion engine housing a reciprocable piston, said method comprising:

defining, by means of wall means carried by and movable with said reciprocable piston, 21 series of spaced and mutually distinct streams of air flowing between the interior and exterior of a combustion zone of a cylinder generally along a cylindrical surface extending coaxially of the axis of reciprocation of a piston mounted within said cylinder;

defining a series of spaced streams of fuel projecting into the interior of said combustion zone of said cylinder, said fuel streams being generally alined with a conical plane diverging generally toward said piston and coaxially alined with the axis of reciprocation of said piston within said cylinder;

passing each said fuel stream through one of said airstreams;

the passing of said fuel streams through said airstreams defining a series of mutually distinct fuel and airstream intersection zones spaced circumferentially about said axis of reciprocation;

directing air and fuel streams entering each intersection zone through generally turbulent flow patterns tending to shear and disperse fuel particles of the fuel stream entering each intersection zone through the airstream entering each intersection zone;

burning at least some of said fuel in said spaced and mutually distinct intersection zones in the form of spaced burning loci while concurrently projecting fuel from said fuel streams thereinto; substantially maintaining the burning of said fuel in said spaced and mutually distinct intersection zones; and

moving said wall means which define said airstreams generally away from a source of said fuel streams while fuel is being projected into said burning loci and while said wall means provide paths of limited communication between said combustion zone and said exterior of said combustion zone, which exterior comprises a working zone of said engine in direct communication with said reciprocable piston. 4. A method of burning fuelwithin the cylinder of an internal combustion engine housing a reciprocable piston, said method comprising:

defining a series of spaced and mutually distinct streams of air flowing between the interior and exterior of a combustion zone of a cylinder generally along a cylindrical surface extending coaxially of the axis of reciprocation of a piston mounted within said cylinder;

passing each said fuel stream through one of said airstreams;

the passing of said fuel streams through said airstreams defining a series of mutually distinct fuel and airstream intersection zones spaced circumferentially about said axis of reciprocation; directing air and fuel streams entering each intersection zone through generally turbulent flow patterns tending to shear and disperse fuel stream entering each intersection zone through the airstream entering each intersection zone; burning at least some of said fuel in said spaced and mutually distinct intersection zones in the form of spaced burning loci while concurrently projecting fuel from said fuel streams thereinto;

substantially maintaining the burning of said fuel in said spaced and mutually distinct intersection zones;

each of said airstreams entering said combustion zone of said cylinder through an airstream defining orifice, with said orifice associated with each airstream extending in general longitudinal alinement with a plane which is parallel to the axis of reciprocation of said piston;

flowing each of said airstreams generally along a cylindrical wall portion of said combustion zone toward a closed end of said combustion zone, said wall portion providing said cylindrical surface;

deflecting each said airstresm from said cylindrical wall to cause each said airstream to flow along a generally arcuate path leading consecutively toward said axis of reciprocation and generally away from said closed end of said combustion zone;

projecting each of said fuel streams into said combustion zone in general alinernent with said conical plane, which plane diverges away from said closed end of said combustion zone and intersects all of said orifices;

said orifices being substantially alined with, and circumferentially spaced about, a circle extending perpendicular to said axis of reciprocation;

moving said orifices away from said closed end of said cornbustion zone during said burning;

causing each said fuel stream to continuously intersect one of said orifices throughout said burning; and

during said moving of said orifices away from said closed end of said combustion zone, terminating the projecting of said fuel streams into said combustion zone and discharging products of combustion out of said combustion zone through said orifices into an expansibie chamber communicating with said piston.

5. A method as defined in claim 4:

wherein prior to said defining of said mutually distinct airstreams, a body of air within the interior of said cylinder is compressed and heated by reciprocating movement of said piston;

wherein said compressed and heated body of air is caused to flow radially inwardly toward said axis of reciprocation and is thereafter deflected generally away from said piston to flow through said orifices;

wherein during movement of said piston away from said combustion zone, heated and compressed air within said combustion zone first flows out of said combustion zone through said orifices generally toward said piston, con current with the projecting of said fuel streams, and thereafter is deflected to flow generally radially outwardly of said axis of reciprocation; and

wherein said orifices substantially control fluid communication between said combustion zone and a reaction zone and a reaction surface of said piston radially encircling said projection throughout an increment of rotation of said crankshaft commencing prior to said initial projecting of said fuel streams and terminating after the cessation of said projecting of said fuel streams.

6. A method of burning fuel in a combustion zone located in the cylinder head of an engine cylinder head of an engine cylinder housing a reciprocating piston, said method comprising:

defining a plurality of spaced burning loci within the cylinder of an engine, with each of said loci communicating with a combustion zone located in a cylinder head of said engine;

mixing and agitating fuel and air in each of said spaced loci;

. burning fuelin said spaced loci and concurrently projecting fuel thereinto;

discharging products of combustion from said spaced loci into an expansible working chamber communicating with said reciprocating piston;

defining, by means of a plurality of orifice forming wall means carried by and movable with said reciprocating piston, a series of spaced airstreams flowing between said combustion zone and said working chamber;

projecting fuel into said combustion zone with at least some of said fuel passing through at least some of said airstreams for said mixing and agitating; and

moving said orifice forming wall'means which define said airstreams generally away from said cylinder head while fuel is being projected into said burning loci and while said'orifice forming wall means provide paths of limited communication between said combustion zone and said working chamber.

7. A method of burning fuel in a combustion zone located in the cylinder head of an engine cylinder housing a reciprocating piston, said method comprising:

mixing and agitating fuel and heated air in each of said spaced loci;

burning fuel in said spaced loci;

moving said loci away from said cylinder head while burning fuel therein and while projecting fuel thereinto;

moving said orifice forming wall means which define said airstreams generally away from said cylinder head while fuel is being projected into said burning loci and while said orifice forming wall means provide paths of limited communication between said combustion zone and said working chamber.

8. An apparatus for burning fuel within the cylinder of an internal combustion engine housing a reciprocable piston, said apparatus comprising: it

wall means carried by and movable with said reciprocable piston and operable to define a series of spaced and mutually distinct airstreams flowing between the interior and exterior of a combustion zone of said cylinder;

means including a fuel source operable to define a series of spaced and mutually distinct streams of fuel projecting into said combustion zone; means operable to define a series of spaced and mutually distinct fuel stream and airstream intersection zones which form burning loci;

means operable to cause said fuel streams to project fuel into said burning loci; and

said piston being operable to move said wall means which define said airstreams generally away from said fuel source while said fuel streams are being projected into said burning loci and while said wall means provide paths of limited communication between said combustion zone and said exterior of said combustion zone, which exterior comprises a working zone of said engine in direct communication with said reciprocable piston.

9. An apparatus for burning fuel within the cylinder of an internal combustion engine housing a reciprocable piston, said apparatus comprising:

wall means carried by and movable with said reciprocable piston and operable to define a series of spaced and mutually distinct streams of heated air flowing between the interior and exterior combustion zone of a cylinder generally along a cylindrical surface extending coaxially of the axis of reciprocation of said piston which is mounted within said cylinder;

means including a fuel source operable to define a series of spaced and mutually distinct streams of fuel projecting into the interior of said combustion zone of said cylinder, with each said fuel stream being generally alined with a conical plane diverging away from said combustion zone and coaxially alined with the axis of reciprocation of said piston within said cylinder; means operable to define a series of mutually distinct fuel and airstream intersection zones which form burning loci, spaced circumferentially about said axis of reciprocation; means for projecting fuel into said zones during movement of said piston away from said combustion zone; and said piston being operable to move said wall means which define said airstreams generally away from said fuel source while said fuel streams are being projected into said burning loci and while said wall means provide paths of limited communication between said combustion zone and said exterior of said combustion zone, which exterior comprises a working zone of said engine in direct communication with said reciprocable piston.

10. An apparatus as defined in claim 9 further including:

means operable, prior to said defining of said mutually distinct airstreams, to compress and heat a body of air within said working zone;

means operable to cause said compressed and heated body of air to flow radially inwardly toward said axis of reciprocation and thereafter be deflected generally away from said piston to flow through said paths and thereby define said airstreams;

means operable during movement of said piston away from said combustion zone to cause heated and compresses air within said combustion zone to first flow out of said combustion zone, through said paths, and generally toward said piston concurrent with said projecting of fuel into said zones, and thereafter be deflected to flow generally radially outwardly of said axis of reciprocation;

said piston including a reaction surface in said working zone; and

said paths being operable to substantially limit fluid communication between said combustion zone and said reaction surface of said piston commencing prior to said projecting of said fuel streams and terminating after the cessation of said projecting of said fuel streams.

11. A method of heating and dispersing fuel in an internal combustion engine, said method comprising:

providing a series of spaced zones including flow paths carried by and movable with a reciprocating piston of said engine and operable to substantially control fluid communication between a combustion chamber and a working chamber of a cylinder of said engine;

projecting a plurality of generally spaced fuel streams into said combustion zone, with at least some of said fuel streams projecting fuel into at least some of said spaced zones and forming spaced burning loci;

moving said flow paths generally toward said working chamber; and

during said movement of said flow paths generally toward said working chamber, passing heated air from said combustion chamber under relatively high velocity through said flow paths, while concurrently projecting fuel from said fuel streams into said spaced zones; and

said said moving of said flow paths generally toward said working chamber while concurrently projecting fuel into said spaced zones occuring, at least in part, while said flow paths limit communication between said combustion chamber and said working chamber.

mg UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3, 543, 735 D d December 1, 1970 Inventor(s) KRUCKENBERG ET AL It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 3, line 61, change "alined" to aligned Column 3, line 73, change "alined" to aligned Column 4, line 18, change 'alined" to aligned Column 4, line 43, after "six" add such Column 4, line 72, change "intersect" to intersects Column 5, line 3, after "structure" (first occurrence) omit "of the structure".

Column 5, line 10, change "alined" to aligned Column 5, line 12, change "alinement" to alignment Column 5, line 16, change "withing" to within Column 5, line 16, change "alinement" to alignment Column 5, line 17, change "alinement" to alignment Column 5, line 28, change "alined" to aligned Column 5, line 38, change "alined" to aligned Column 5, line 52, change 'face" to faces Column 6, line 74, change "alined" to aligned Column 7, line 20, change "coverage" to converge Column 8, line 10, change "taken" to take Column 8, line 12, change "inpinge" to impinge Column 8, line 55, after "about" add point Column 9, line 65, after "tion" add of Column 9, line 70, change "Froelich" to Froehlich Column 11, line 5, change "alined" to aligned Column 11, line 7, change "alined" to aligned Column 11, ,line 43, change "alined" to aligned Column 11, line 45, change "alined" to aligned Column 11, line 54, after "fuel" add particles of the fuel Column 11, line 66, change "alinement" to alignment Column 12, line 5, change "alinement" to alignment L. Contd on page 2) Page 2 825 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent N 735 Dated December 1, 1970 Inventor(s) KRUCKENBERG ET AL It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 12, line 8, change alined" to aligned Column 12, line 38, after "and" omit "a reaction zone".

Column 12, line 39, omit "and".

Column 12, line 45, after "cylinder" (second occurrence) omit "head 0:

an engine". Column 12, line 46, omit "cylinder". Column 13, line 62, change "alinecl' to aligned Column 14, line 27, change "compresses to compressed Column 14, line 58, after "said' (first occurrence) omit "said".

Signed and sealed this 30th day of March 1971.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. WILLIAM E. SCHUYLEH, JR. Attesting Officer Commissioner of Patents