US 2172170 A
Description (OCR text may contain errors)
Sept. 5, 1939.- J. P. MEGROO T I INTERNAL COMBUSTION ENGINE- Filed June 17, 1959 2 Sheets-Sheet 2 v INVENTOR.
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Min Pefef @raai ATTORNEYS Patented Sept. 5, 1939 UNITED STATES PATENT OFFICE 2,172,170 INTERNAL COMBUSTION ENGINE John Peter Megroot, Cleveland, Ohio A Application June 17, 1939, Serial No. 279,593
This invention refers to a method (and means) for bringing about an efficient vortex .or whirl in a combustible mixture for an oil engine formed by vaporization at comparatively high temperature, or a combustible mixture formed by mechanical pulverization or atomization, and for preventing the hard burning oils or fuels from reaching the cooler parts of the combustion chamber by shaping a piston head, and a cylinder.
head, so that the interengaging parts thereof enter into engagementwith play forcing the compressed medium circumferentially of the interengaging portions inwardly through converging passages provided in the cylindrical plug formed on the piston head, which passages are tangential with respectto acentral bore formed therein. The vena contracta orpoint of greatest contraction of each passage or conduit being in close proximity to or with the floor of the central bore, the passages or conduits providing means for causing the fuel charge in the central bore to rotate about the wall thereof when the compressed medium is forced therethrough.
The upper face of the piston leading down to uration or may be otherwise suitablyldesigned .to break up the charge by meansofsharp angles that also provide hot areas in .th'e piston face above and around the central bore. 7.
Accordingly this invention obviates difficulties.
which have been experienced due v,tochillingpf the injected fue l;coming into contact withthe, colder surrounding water cooled enginecylinden.
Other objects of the invention will appear from the following description;
The invention and its aims and objects willv be readily understood from the following description taken in connection with the accompanying drawings, embodying my invention, herein given for illustrative purposes, the true scope of the invention being more particularly pointed out in the appended claim.
Apparatus according to the invention is illusthe central bore is of truncated conical config-,
Like reference characters refer to like parts throughout the several views.
In one construction according to this invention, the engine comprises a working cylinder Ill provided with a water jacket II and a cylinder 6 head l2 on which there is formed or otherwise attached an annular flange or skirt I3 projecting into the cylinder beyond the cylinder head. The. cylinder .head is provided with valve-controlled inlet and exhaust ports, two of which are shown 9. as at M and I5. The fuel injection nozzle I6 is shown in its receiving opening as at I! in the cylinder head.
In accordance with the usual practice, a piston. I8 is reciprocally mounted within the cylinder I0. 5 On the face of the piston there is provided a cylindrical plug l9 which interengages with play, the annular portion or flange formed on the cylinder head.
The cylindrical plug is provided with a central 20 faces are adapted to promote separation and combustion of the fuel charge.
vIn the cylindrical plug portion there is pro- 'vlded,a plurality of converging passages or conduitsi which are tangential with respect to the central bore. greatest contraction or smallest cross-section of each passage 29, 30 and 3!, being in close proximity to or with the bottom wall or floor 20' of the. central bore. The leakage space between the cylindrical plug and the annular flange or skirt on the cylinder head is shown at 32 and 33.
When the compressed medium circumferentially of the interengaging portions is forced'inwardly through the tangential passages, the fuel charge in the central bore is caused to rotate about the wall of the central bore.
In the construction shown in Figures 3 and 4 the inwardly projecting flange on the cylinder head is not found. The piston operating in the wise the configuration of the piston head is the a The vena contracta or point of same as that shown in Figure 1, that is with faces, shoulders, and converging conduits.
An air compressor, which it is believed unnecessary to give a special drawing thereof, may be of the usual construction, and may be arranged and connected with the annular space to force the compressed medium into and through the converging passages in the piston head and into the central bore. A connection for the air compressor is shown at 38. A booster compressor is shown at 39.
Booster compression arrangement for a. 4 cycle engine In this arrangement extra compression is brought about by an outside booster compressor. As shown, a separate compressor is used for each cylinder, however, a single compressor can be readily arranged to supercharge each of a plurality of cylinders. The cycle of operation is as folows:
Suction stroke.The working piston goes down, the booster plunger up, permitting air to enter both cylinder and compressor.
Compression stroke.The working cylinder moves up compressing the air therein and because of direct connection of cylinder and compressor, the pressure in both is necessarily equalized. This compression raises the temperature of the compressed medium by virtue of the work performed thereon and thus heats the piston head, ducts and so forth. Immediately prior to the fuel injection, the compressor piston or plunger is forced down (by cam or other mechanical movement) raises the compression value of the already compressed medium and forces such higher compressed air into the annular recess, through the tangential ducts into the central bore and also through the leakage space. The tube from the compressor, the annular recess, the tangential conduits, etc., being in the path of the higher compressed medium from the compressor, continue to bleed the higher compressed air into the combustion space during the injection and firing period thus acting as storage cells for the energy delivered by the compressor. In effect, they tend to prolong the vortex motion of the medium in the central bore well into the firing period. The compressor plunger is now in the down position and remains in said position as a check valve until the next suction stroke.
Power stroke-The working piston is moving down and the compressor plunger remains in the down position.
Exhaust stroke-The working piston moves upwards and scavenges the cylinder until the intake valves open.
Booster compression arrangement for a 2 cycle engine (1) Power stroke-The booster plunger is .down. The Working piston moves downward under the expanding gas of combustion. Scavenging is complete after piston is down.
(2) Compression stroke.The working piston moves upwards and the boooster plunger is raised instantaneously permitting air charge to enter booster cylinder. The working piston moving upwards compresses the air in both the cylinder and the compressor. Near the end of the working pistons compression stroke, shortly before injection, the booster plunger moves down rapidly and stays down during the entire firing stroke.
The compressed air enters the compressor at a high temperature by virtue of the work performed upon it by the working piston. The booster plunger in its properly timed stroke compresses the medium to a higher pressure and consequently to a higher temperature. Said higher compression medium moves to the point of lower pressure, in the cylinder, by way of the shortest route, namely, into the annular recess, through the conduits into the central bore and through the leakage space.
Passing through the progressively tapering conduits, the medium enters the central bore rotating rapidly by virtue of the tangential relationship.
The annular recess and the converging ducts, because of the higher compression therein, due to the action of the compressor, act as energy cells, maintaining the flow of air into the central bore, until the higher compressor pressure hasbeen reduced to the pressure of the cylinder proper. The maintenance of the energy cell action prolongs the vortex action so that the vortex and the shoulders on the piston head are able to bring about a. nearly complete centrifugal separation of the fuel components; thus making it impossible for the hard to burn oils to chill below their combustion temperature during the volatilization of the lighter fuel components. The sharp corners of the piston head, because of their physical proportions, being of a higher temperature, aid in the combustion of the hard to burn oils, while the lighter combustion gases are held in the central portion of the vortex.
It is important to note that. the arrangement of the annular recess and the leakage space thereabove, bring only compressed air and not products of combustion inv contact with the cylinder wals at the junction of the piston and cylinder, so: that it is only possible for compressed air and not carbon loaded combustion gases to leak past the piston rings into the crank case. As a result the engine oil is not diluted by or thickened by fuel oil or carbon particles.
I am aware that the invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof; and I therefore desire the present embodiment to be considered in all respects as illustrative and not restrictive, reference being had to the appended claim rather than to the foregoing 1description to indicate the scope of the invenion.
Having thus described my invention, what I claim is:
In an internal combustion engine, the combination of a jacketed working cylinder, a piston reciprocating therein, having a cylindrical plug projecting from the piston head and having formed. therein a central bore forming an auxiliary chamber, and leading upward divergingly therefrom a combustion chamber having therein a multiplicity of concentric surfaces, each of the aforesaid multiplicity of surfaces being bounded by a wall, said cylindrical plug also having formed therein a plurality of diverging conduits extending from the external periphery of said cylindrical plug and opening tangentially with respect to the wall of said central bore, a cylinder head having intake and exhaust ports and an opening adapted to receive a fuel injection nozzle, and an annular flange projecting into the working cylinder, said annular flange having an internal diameter greater than the external diameter of the cylindrical plug on the piston head, whereby at top dead center position of said piston, there is defined by said external diameter of the cylindrical plug and the inner periphery of the annular flange and the inner face of the cylinder head a leakage space which communicates with the combustion chamber in the cylindrical plug, and whereby a portion of the compressed medium is forced inwardly through the diverging conduits into the central bore, the surfaces and walls in the combustion chamber being adapted to influence the movement of the entering charge in planes transverse thereto so that portions of the charge will be distributed on the surfaces and walls to increase firing efiiciency.
JOHN P. MEGROOT.