CONCENTRIC INTERNAL COMBUSTION ROTARY ENGINE
An internal combustion rotary engine includes a housing having an inlet and an outlet and a rotatable rotor centrally mounted within the housing. The rotor includes a plurality of pockets located about its circumference, the rotor further being connected to a rotor shaft. A rotatable elliptical body is disposed in each of the plurality of pockets. Each rotatable elliptical body is coupled to respective planet gears and each respective planet gear is meshed with a centrally disposed fixed sun gear. An ignition source is disposed in each of the plurality of pockets for igniting a fuel/air mixture. During operation of the internal combustion rotary engine, for each 360° rotation of the rotor, each elliptical body rotates through 720°.
This Application claims priority to U.S. Provisional Patent Application No. 60/587,948 filed on Jul. 14, 2004. The '948 Application is incorporated by reference as if set forth fully herein.
FIELD OF THE INVENTIONThe field of the invention generally relates to combustion engines. More specifically, the field of the invention relates to internal combustion rotary engines.
BACKGROUND OF THE INVENTIONCombustion engines that operate using a reciprocating piston suffer from a number of disadvantages. First and foremost is the inefficient manner in which components such as, for example, pistons are repeatedly accelerated, stopped, and reversed during operation of the engine. In this regard, conventional piston-based engines are both unbalanced and inefficient due to the constant momentum changes occurring within the engine. It has been estimated, for example, that about 13% of fuel energy is lost in a conventional piston-based engine due to internal friction and pumping losses.
In addition, in conventional piston-based engines, there is only a brief moment (if at all) when the torque arm is in its optimum configuration with the piston/connecting rod. This typically occurs a few degrees before the middle of the piston stroke. In fact, a true 90° (optimal) torque arm is never achieved in a conventional piston-based combustion engine.
The internal combustion rotary engine is one alternative to piston-based combustion engines which can mitigate, to some extent, these inherent inefficiencies. Felix Wankel is credited with inventing an internal combustion rotary engine which operates by using a triangular-shaped rotor spinning within a housing shaped in the manner of a epitrochoid (e.g., peanut-shaped). The internal combustion rotary engine includes a number of advantages over piston-based combustion engines.
First, internal combustion rotary engines are more lightweight and compact. Second, internal combustion rotary engines are smoother since there is no reciprocating motion of pistons. Third, internal combustion rotary engines have an extended power stroke rotation of the output shaft as compared to their piston-based counterparts. Fourth, there are fewer moving parts, e.g., no valves, connecting rods, cams, and timing chains. Timing of the intake and exhaust strokes are accomplished directly by the motion of the rotor. Fifth, internal combustion rotary engines have a generally flat torque curve because no valves are used. Sixth, combustion in internal combustion rotary engines are generally cooler than their piston-based counterparts. This means fewer oxides of nitrogen are created. Finally, internal combustion rotary engines separate the combustion region from the intake region, thereby making these engines good candidates for hydrogen fuel-based engines.
The problem with Wankel-type internal combustion rotary engines is that they generally leak combustion gases, making these types of engines less desirable. In addition, the rotational speed (i.e., revolutions per minute (RPM)) of Wankel-type internal combustion rotary engines is limited because of the manner in which the triangular rotor flip-flops around the interior of the epitrochoid housing.
There thus is a need for a true internal combustion rotary engine that is not limited in its rotational speed. In addition, there is a need for an internal combustion rotary engine that has very low emissions. In addition, there is a need for an internal combustion rotary engine that has high horsepower and high torque while at the same time is fuel efficient.
SUMMARY OF THE INVENTIONAn internal combustion rotary engine includes a housing having an inlet and an outlet and a rotatable rotor centrally mounted within the housing. The rotor includes a plurality of pockets located about its circumference. The rotor is further connected to a rotor shaft that is mechanically connected to an output shaft. A rotatable elliptical body is disposed in each of the plurality of pockets. Each rotatable elliptical body is coupled to respective planet gears. Each of the respective planet gears is meshed with a centrally disposed fixed sun gear. In addition, an ignition source is disposed in each of the plurality of pockets. For each 360° rotation of the rotor, each elliptical body rotates through 720°. The rotary engine includes four separate regions in which the intake, compression, power, and exhaust strokes take place.
In one aspect of the invention, the rotor includes three pockets located about its circumference. The pockets may be equally spaced about the circumference of the rotor.
In another aspect of the invention, an internal combustion rotary engine includes a housing having an inlet and an outlet, the inlet being coupled to a compressor. A rotatable rotor is centrally mounted within the housing. The rotor includes a plurality of pockets located about its circumference. The rotor is connected to a rotor shaft, which in turn, is coupled to an output shaft. An elliptical body is disposed in each of the plurality of pockets with each elliptical body being mounted on a rotational shaft at one end and coupled at an opposing end to a planetary gear. Each planet gear is engages with a fixed, centrally located fixed sun gear. An ignition source is disposed in each of the plurality of pockets. For each full rotation of the rotor (i.e., 360°) each elliptical body rotates through 720°.
In another aspect of the invention, each elliptical body includes a seal disposed on an exterior surface thereof. In still another aspect of the invention, the elliptical body is interposed between two outer spools to form an elliptical body assembly. In yet another aspect of the invention, the rotor is coupled to a distributor. The distributor rotates with the rotor and includes an electrical contact for each ignition source (e.g., three electrical contacts).
In another aspect of the invention, the rotor shaft includes a passageway or bore therein in fluid communication with a bore in the rotational shaft of the elliptical body assembly. The passageway and bore provide an access path for oil or other lubricant to lubricate the elliptical body bearings, and the planetary and sun gears. In one preferred aspect of the invention, each planet gear has a pitch diameter that is equal to the pitch diameter of the sun gear.
It is an object of the invention to provide an internal combustion rotary engine that has high horsepower, very high torque, and very low emissions. It is a further object of the invention to provide an internal combustion rotary engine that is balanced and uses a rotor that rotates about a single axis. It is yet another object of the invention to provide an internal combustion rotary engine that uses a concentrically balanced rotor.
BRIEF DESCRIPTION OF THE DRAWINGS
A rotatable rotor 12 is disposed centrally inside the housing 4. The rotor 12 is mounted on a rotor shaft 14 and is rotatable within the housing 4 in the direction of arrow C in
As seen in
During operation of the engine 2, the elliptical bodies 22 rotate in the direction of arrow D in
In one preferred aspect of the invention, the elliptical bodies 22 are formed from industrial ceramic materials although other materials such as metals and alloys can also be used. Preferably, the elliptical bodies 22 are machined or otherwise formed with strict tolerances in order to minimize any leakage of air and/or fuel between the elliptical bodies 22 and the interior of the housing 4. In addition, the elliptical bodies 22 are preferably sealed inside the pockets 20, for example, via seals 96.
With reference now to
Referring to
Referring back to
Referring to
For example, in an engine 2 having a rotor 12 with a diameter of 15.5 inches, elliptical bodies having dimensions of 3 inches by 1.5 inches, planetary gears of 7 inch diameter, the engine is able to achieve a compression ratio of about 10.58. The compressor 8 is able to double the compression ratio of engine 2 from about 5.29 to about 10.58.
Referring to
With reference not to
As best seen in
Still referring to
As explained above, in one aspect of the invention, the housing 4, when viewed in cross-section, has a profile of a spline curve. Tables 1 and 2 reproduced below illustrates the radius of the internal surface of the housing 4 at 2° increments through 180° (the measurements for the remaining 180° are not included because the symmetrical nature of the housing 4). Radius measurements are provided for an interference fit between the elliptical bodies 22 as well for a running fit. The running fit includes an approximate clearance of 0.002 inches between the elliptical bodies 22 and the interior of the housing 4. The measurements assume a 1.5 inch minor axis and 3 inch major axis for the elliptical bodies 22. The radius of the rotor 12 is assumed to be 7.5 inches and the radius of the centers of the elliptical bodies 22 is assumed at 7 inches.
During operation of the engine 2, as the elliptical body 22 clears the inlet 6 or intake port, the air/fuel charge follow behind and fills the intake sweep (i.e., region 100 in
It should be noted that the building pressure in the confined area does not work against the engine 2 as in a conventional piston engine. With reference to the lower right elliptical body 22, after completion of the power stroke, the elliptical body 22 actually aids in expelling combustion gases from the engine 2 via the outlet 10. This occurs for each elliptical body 22 (e.g., three in a preferred embodiment of the invention), thereby producing the same number of power strokes per revolution as a conventional six cylinder, four stroke piston-based engine.
The present engine 2 can be used in any applications where combustion engines are typically used, for example, automobiles and planes. The engine 2 may be used in hydrogen-powered applications. Multiple rotors 12 can also be used to increase the output of the engine 2. The present engine 2 produces motion which is entirely concentric and thus is in dynamic balance. There is no flip-flop motion associated with the rotor 12 as is present, for example, in the Wankel-type rotary combustion engines. The present engine 2 is able to rotate at high rates, for example, between about 25,000 and 50,000 RPM. This compares favorable with piston engines which revolve at a rate between about 4,000 and 6,000 RPM.
The practical RPM of the engine 2 will be very high, similar to that of a turbine. In addition there is little bypass of gases. The very long torque arm will generate high torque and the long swept volume will cause the complete combustion of the fuel, leaving a very clean, cool exhaust. It is estimated that the engine 2 can offer an 18% increase in efficiency over a modern reciprocating engine.
While embodiments of the present invention have been shown and described, various modifications may be made without departing from the scope of the present invention. The invention, therefore, should not be limited, except to the following claims, and their equivalents.
Claims
1. An internal combustion rotary engine comprising:
- a housing having an internal surface which is substantially symmetrical about a minor-axis centerline of said housing, an inlet disposed on one side of the minor-axis centerline of the housing and an outlet disposed on an opposing side of the minor-axis centerline of the housing; and
- a rotor assembly concentrically mounted in the housing in relation to the inner surface of the housing, and a rotational axis of the rotor assembly being substantially perpendicular to the minor-axis centerline of the housing and a major-axis centerline of the housing, the rotor assembly comprising: a rotatable rotor comprising a rotor shaft, a substantially solid circumferential surface, and a plurality of pockets located about the circumference of the rotor, a center of each respective one of the plurality of pockets being located substantially equidistant from the center of the rotor; a rotatable elliptical body having a substantially solid outer surface and disposed in each of the plurality of pockets, each elliptical body being mounted to the rotor such that an axis of rotation of the elliptical body is centrally located at the center of the pocket, each rotatable elliptical body having a drive shaft that is coupled to an elliptical body driving mechanism that causes the elliptical body to rotate about its axis of rotation in correspondence with rotation of the rotor, wherein, when the elliptical body is rotated about its axis, the outer surface of the elliptical body engages the inner surface of the housing, and a portion of the outer surface nearest the vertices along a major-axis of each elliptical body engages a surface of the respective pocket in which the elliptical body is mounted, and
- wherein, as the rotor rotates concentrically within the housing through one revolution, each elliptical body rotates correspondingly through two revolutions about its axis, and the elliptical body, by engaging the inner surface of the housing and the pocket during the rotation, causes a first increase in volumetric displacement in an intake region, a corresponding first decrease in volumetric displacement in a compression region, a second increase in volumetric displacement in a power stroke region, and a corresponding second decrease in volumetric displacement in an exhaust region.
2. The internal combustion rotary engine of claim 1, wherein the rotor includes three pockets located about its circumference.
3. The internal combustion rotary engine of claim 2, wherein the three pockets have an equal angular spacing about the center of the rotor.
4. The internal combustion rotary engine of claim 1, further comprising an ignition device disposed in each pocket.
5. The internal combustion rotary engine of claim 1, wherein the elliptical body driving mechanism comprises a planet gear connected to the drive shaft of the elliptical body, and a sun gear engaging the planet gear concentrically mounted about the rotor shaft.
6. The internal combustion rotary engine of claim 1, further comprising an output shaft mechanically geared with the rotor shaft.
7. The internal combustion rotary engine of claim 1, further comprising an exhaust gas purge port disposed in the plurality of pockets in the rotor.
8. The internal combustion rotary engine of claim 1, further comprising a compressor coupled to the inlet of the housing.
9. The internal combustion rotary engine of claim 6, wherein the rotor shaft is mechanically coupled to the output shaft via a jack shaft.
10. The internal combustion rotary engine of claim 1, wherein each elliptical body includes a seal substantially disposed on the exterior surface nearest the vertices along a major axis of the elliptical body.
11. The internal combustion rotary engine of claim 1, wherein each elliptical body is interposed between two outer circular members.
12. The internal combustion rotary engine of claim 4, wherein the rotor is coupled to a distributor, and the distributor includes an electrical contact for each ignition device.
13. The internal combustion rotary engine of claim 1, wherein in the intake and compression regions, a fuel/air mixture is introduced into the inlet of the housing and is compressed by the rotation of the elliptical body into a combustion chamber defined by the surface of the pocket and the outer surface of the elliptical body.
14. The internal combustion rotary engine of claim 13, wherein the fuel/air mixture compressed within the combustion chamber defined by the surface of the pocket and the surface of the elliptical body is ignited by the ignition device.
15. The internal combustion rotary engine of claim 14, wherein in the power stroke and exhaust regions, the ignited fuel/air mixture is burned and then exhausted through the outlet of the housing.
16. The internal combustion rotary engine of claim 1, wherein the rotor shaft includes a passageway therein in communication with a bore contained in the drive shaft of the elliptical body, as a path of lubrication.
17. The internal combustion rotary engine of claim 5, wherein each planet gear has a pitch diameter equal to the pitch diameter of the sun gear.
18. The internal combustion rotary engine of claim 1, further comprising a first seal member in the housing surface located along the minor-axis centerline of the housing between the inlet and the outlet, and a second seal member in the housing surface substantially opposed to the first seal member along the minor-axis centerline of the housing, said first and second scat members engaging with the circumferential surface of the rotor and the surface of each elliptical body so as to form an intake/compression chamber on the inlet side of the housing, and a combustion/exhaust chamber on the outlet side of the housing.
19. The internal combustion rotary engine of claim 1, wherein the inner surface of the housing has a substantially epitrochoid-like shape.
20. A method for an internal combustion rotary engine, the engine comprising (1) a housing having an internal surface which is substantially symmetrical about a minor-axis centerline of said housing, an inlet disposed on one side of the minor-axis centerline of the housing, and an outlet disposed on an opposing side of the minor-axis centerline of the housing; and (2) a rotor assembly concentrically mounted ill the housing in relation to the inner surface of the housing, and a rotational axis of the rotor assembly being substantially perpendicular to the major-axis centerline of the housing and a major-axis centerline of the housing, the rotor assembly comprising (a) a rotatable rotor comprising (i) a rotor shaft, (ii) a substantially solid circumferential surface, and (iii) a plurality of pockets located about the circumference of the rotor, a center of each respective one of the plurality of pockets being located substantially equidistant from the center of the rotor, (b) a rotatable elliptical body having a substantially solid outer surface and disposed in each of the plurality of pockets, each elliptical body being mounted to the rotor such that an axis of rotation of the elliptical body is centrally located at the center of the pocket, each rotatable elliptical body having a drive shaft that is coupled to an elliptical body driving mechanism that causes the elliptical body to rotate about its axis of rotation in correspondence with rotation of the rotor, wherein, when the elliptical body is rotated about its axis, the outer surface of the elliptical body engages the inner surface of the housing, and a portion of the outer surface nearest the vertices along a major-axis of each elliptical body engages a surface of the respective pocket in which the elliptical body is mounted, and wherein, as the rotor rotates concentrically within the housing through one revolution, each elliptical body rotates correspondingly through two revolutions about its axis, and the elliptical body, by engaging the inner surface of the housing and the pocket during the rotation, causes a first increase in volumetric displacement in an intake region, a corresponding first decrease in volumetric displacement in a compression region, a second increase in volumetric displacement in a power stroke region, and a corresponding second decrease in volumetric displacement in an exhaust region, the method comprising:
- introducing a fuel/air mixture into an intake side of the housing, via the housing inlet, between a first one of the elliptical bodies passing the inlet and a second one of the elliptical bodies passing the inlet;
- compressing the fuel/air mixture by rotating the rotor and the second elliptical body until the fuel/air mixture is compressed within the pocket of the second elliptical body between the surface of the pocket and the surface of the second elliptical body;
- igniting the compressed fuel/air mixture within the pocket of the second elliptical body;
- burning the ignited fuel/air mixture in a combustion side of the housing in a chamber formed between the second elliptical body and the inner surface of the housing so as to power the rotation of the rotor; and
- exhausting the burned fuel/air mixture from the housing via the outlet after the second elliptical body passes the outlet.
Type: Application
Filed: Jul 8, 2005
Publication Date: Mar 29, 2007
Inventor: Robert Campbell (Hesperia, CA)
Application Number: 11/177,175
International Classification: F02B 53/00 (20060101);