Abstract:
A stationary crankshaft, cylindrical rotor, low friction, adjustable timing, pistonless, rotary internal combustion engine. A cylindrical rotor rotates freely about a stator, also cylindrical in shape. A plurality of cavities are circumferentially disposed along the external circumference of the stator and the internal circumference of the rotor that, when rotationally aligned, form combustion chambers. Rotation of the rotor is induced by electrical-spark induced combustion of a fuel/air mixture in the combustion chambers. The combustive exhaust is vented into an exhaust manifold for transport to an exhaust disposal system, such as a catalytic converter. Cooling, fuel pressurization, and electrical generation can be internal to the engine or supplied externally. Engine speed, torque, and other operational requirements can be accommodated by coupling multiple rotational units together and engine vibration can be virtually eliminated by offsetting the combustion chambers on coupled units.

Description:
FIELD OF THE INVENTION 
     The present invention pertains to internal combustion engines and, more particularly, to stackable, low friction, stationary crankshaft, cylindrical rotor, multi-stage, pistonless, rotary internal combustion engines, including means for venting exhaust gases and supplying cooling, electrical power, lubrication, fuel, and air to the engines. 
     BACKGROUND OF THE INVENTION 
     Over the final decades of the twentieth and the first decade of the twenty-first centuries, the unpredictable and finite nature of non-renewable fossil fuel supplies has become increasingly apparent. Ironically, this realization has come at the precise moment when the industrialized nations of the world are demanding engines with greater power output, increased service life, and improved flexibility for automotive, military, aeronautical, and other applications. With more and more nations achieving industrialization, skyrocketing demand and fierce competition for dwindling fossil fuel resources, coupled with greater operational performance requirements, have forced engine designers and manufacturers to consider and pursue alternatives to the inefficient, reciprocating piston, rotating crankshaft, internal combustion engines that have dominated the industry for nearly a century. Presently available alternatives to engines such as hybrid and so-called “green” fuel engines are in their infancy and are unlikely to garner widespread appeal and applicability in the near future. The reasons for this are varied, but include the complexity and expense of these new technologies, the lack of widespread availability of alternative fuels, incompatibility of most alternative fuels with traditional reciprocating engines, and the reluctance of industrialized consumers and industries to sacrifice the power, speed, and reliability of modern reciprocating engines for the, at present, dubious promise of improved fuel efficiency and reduced greenhouse gas emissions. 
     Historically, one alternative to the conventional, reciprocating piston, rotating crankshaft engine has been the rotary internal combustion engine. Compared to the traditional, reciprocating piston engine in which a crankshaft is rotationally driven by reciprocal motion of pistons, the simplest, earliest rotary engines, with their stationary crankshafts and rotating cylinder/piston blocks, achieved higher power-to-weight ratios, were simpler to construct and maintain, had fewer moving parts, had a decreased risk of engine seizure, and experienced lower operational vibration compared to reciprocating, internal combustion engines. The advantages of early, stationary crankshaft, rotating block rotary engines, in which the rotational motion of the cylinder block circumferentially about a stationary crankshaft is still produced via gas pistons, have been common knowledge for almost a century. In fact, rotary-styled, internal combustion engines employing rotating cylinder blocks and pistons were one of the most popular aircraft engine designs in the first quarter of the twentieth century, being employed in more than half of all World War I aircraft. Such engines have seen limited application in automobiles and motorcycles. However, these stationary crankshaft, rotating block rotary engines have historically not proven any more fuel efficient than conventional reciprocating engines and are still plagued with many of the same shortcomings, including high mechanical stresses due to rapid, constant acceleration and deceleration of the cylinder pistons, seal leakage, high unit weight, and overall poor operational efficiencies. Additionally, gyroscopic effects generated by the inertia of the rotating block and the inherent difficulties in controlling engine speed, forced engine designers to concentrate their efforts on improving the operational characteristics of the traditional, reciprocating piston engines by the mid 1920s. 
     Another alternative to the reciprocating piston engine, the pistonless, rotary internal combustion engine, in which a rotor is used rather than pistons, has the potential for even higher power-to-weight ratios and greater fuel efficiency than rotating block, stationary crankshaft rotary engines. These engines also have the potential for longer operational life due to the virtual elimination of the high mechanical stresses caused by the constant, rapid acceleration and deceleration of the pistons, cylinders, and associated parts in the piston-driven, reciprocating and rotating block, stationary crankshaft rotary engines. Additionally, the elimination of moving cylinders, pistons, and associated hardware render the pistonless, rotary internal combustion engine lighter, more reliable, and far less prone to catastrophic mechanical failure than either the reciprocating or rotating block rotary engines, although maintaining seal integrity becomes difficult as the rotor and housing experience mechanical wear. When new, however, this minimization of moving parts and the very low friction between the rotational and fixed/stationary units significantly increases engine efficiency because less energy is lost to frictional heat generation. In turn, the reduced heat generation in the pistonless, rotary engine translates into reduced reliance on complex cooling systems when compared to conventional, reciprocating and rotating block, stationary crankshaft rotary engines. However, despite the high power-to-weight ratio and other potential benefits, the few existing, modern, pistonless, rotary engines, such as the Wankel engine introduced in the 1960s, in which the rotor assembly is eccentrically rotated about a fixed crankshaft without the aid of gas pistons, are heavily criticized for poor fuel efficiency, incomplete combustion of the air-fuel mixture, high hydrocarbon emissions, inability to effectively couple multiple stages or rotor assemblies together without complex bearing mechanisms, and poor rotor gas seals caused by the mechanical wear of the three-sided, eccentric rotor assembly and the engine housing. 
     Presently, no engine design exists that addresses the shortcomings of the stationary crankshaft, rotating block, rotary internal combustion or the pistonless, Wankel-styled engines. Considering the aforementioned potential advantages of a pistonless, rotary internal combustion engine over traditional reciprocating and rotating block, stationary crankshaft rotary engines in terms of power-to-weight ratios, fuel efficiency, simplicity of construction, reduced maintenance, and lower operational vibration, what is urgently needed is a pistonless, low friction, rotary engine (as well as relatively simple systems for venting exhaust gases and supplying cooling, lubrication, electrical power, fuel, and air to the engine) that provides for more complete fuel-air mixture combustion, greater seal integrity, higher power-to-weight ratios, and increased fuel efficiency than the presently available, reciprocating, rotating block, rotary, or pistonless, Wankel-styled internal combustion engines. Such a solution should be readily adaptable to operation using regular or alternative fuels, such as hydrogen, renewable biofuels, methane, and the like, without sacrificing the engine power and convenience to which the contemporary consumer has become accustomed. Additionally, such a solution could be easily configurable and/or modular, for example, stackable where multiple stages or rotors could be coupled together end-to-end to meet virtually any consumer/operational power requirement. Ideally, a solution could utilize a controlled release (or “bleed off”) system for combustion gases to even further reduce engine vibration caused by combustion of the fuel-air mixture and the concussion of exhaust gases. Additionally, such a solution should permit engine cooling to be by means of forced air, liquid coolants, or some combination of both. 
     DISCUSSION OF RELATED ART 
     The following United States patents and applications address methods and/or apparatus pertaining to rotary or stationary crank internal combustion engines. 
     U.S. Pat. No. 4,318,370, issued to KONTHER, et al. on Mar. 9, 1982, for “Rotary Internal Combustion Engines” teaches a stationary crank engine apparatus consisting of a rotor assembly driven rotationally about a fixed axis by means of two primary and two secondary pistons such that the pistons reciprocate relative to the primary cylinders as the rotor assembly rotates. 
     U.S. Pat. No. 3,739,756, issued to VILLELLA on Jun. 19, 1973, for “Internal Combustion Engine” teaches a conventional, stationary crankshaft, rotating cylinder block, gas piston driven, rotary-styled engine apparatus. Combustion of a fuel-air mixture by electric spark generates axial piston motion and, ultimately, cylinder block rotation circumferentially about the fixed crankshaft. 
     U.S. Pat. No. 1,841,841, issued to MUNN on Jan. 19, 1932, for “Rotary Engine” describes a stationary crankshaft, rotating cylinder block, piston-and-gear driven, rotary-styled engine apparatus. Reciprocating cylinders located on the cylinder block and displaced circumferentially about a centrally positioned, geared crankshaft impart rotational motion to large gears about the crankshaft, causing the entire cylinder block to rotate. 
     U.S. Pat. No. 1,594,035, issued to BAILEY on Jul. 27, 1926, for “Rotary Motor” teaches a rotary motor consisting of internal and external rotor assemblies that rotate synchronously such that the internal rotor is offset from and does not share a common axis with the external rotor assembly. Vanes mechanically conjoined to either the inner or external rotor are the sole means of preventing leakage between chambers. 
     U.S. Pat. No. 1,236,275, issued to DICKSON on Aug. 7, 1917, for “Rotary Engine” teaches a traditional rotary internal combustion engine in which reciprocating gas pistons provide rotational motion of the cylinder block circumferentially about a stationary crankshaft. 
     SUMMARY OF THE INVENTION 
     In accordance with the present invention, there is provided a stackable, stationary crankshaft, cylindrical rotor, low friction, variable timing, pistonless, rotary internal combustion engine having means for venting combustion gases and supplying coolants, lubrication, electrical power, fuel, and air to the engine. The pistonless, rotary, internal combustion engine of the invention and described herein consists of a fixed/stationary unit of cylindrical construction and a rotational unit, also of cylindrical construction, that is free to rotate thereabout. Circumferentially disposed along the external circumference of the fixed/stationary unit and the internal circumference of the rotational unit are a plurality of cavities that, when rotationally aligned, form geometrically distinct combustion chambers. Rotational impetus is provided to the rotational unit by electrical-spark induced combustion of an atomized gas mixture delivered to the combustion chamber via a plurality of fuel lines, nozzles, and ports from a fuel disbursement chamber located within the inner diameter of the fixed/stationary unit. Combustive exhaust and fresh air inlet ports within the combustion cavity are alternatively aligned as the angled/curved surface of the cavity and a strategically placed “bleed off” port directs the combustive force and generates rotational motion of the rotational unit. The combustive exhaust is vented directly into an exhaust manifold for transport to an exhaust disposal system, such as a catalytic converter. 
     Typically, heat energy removal is accomplished using a cooling fan conjoined to the rotational unit of the engine, but may be optionally substituted for or supplemented by a more traditional liquid coolant system. Similarly, the fuel is supplied to the fuel disbursement chamber by means of a fuel pump rotationally conjoined to the rotational unit, but may also be external to the engine. Electrical power generation is accomplished by rotationally conjoining an electrical generator or alternator to the rotating unit. This may be accomplished, for example, by a series of gears and/or pulleys rotationally conjoined to the rotating unit and to an electrical generator. It will be recognized that other mechanisms and/or methods familiar to those skilled in the art may also be used. Consequently, the invention is not limited to any particular mechanism or method of coupling an electrical generator or alternator to the rotating unit. 
     Rotational units or “quads” on successive stages may be coupled together (stacked) such that the combustion chambers of each stage may be aligned, increasing initial rotational torque about the fixed/stationary unit. In alternate embodiments, successive stages may be rotationally/circumferentially offset from one another to provide for smoother and/or faster operation, decrease the time the rotational unit travels due to inertia only, further reduce operational vibration, and diminish the effects of torsional stresses between the fixed/stationary and the rotational units. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A more complete understanding of the present invention may be obtained by reference to the accompanying drawings, when considered in conjunction with the subsequent detailed description, in which: 
         FIG. 1  is a cross-sectional plan view of one level (section) of the rotary engine in accordance with the invention; 
         FIG. 2  is a side, elevational, cross-sectional view of two adjacent sections as shown in  FIG. 1  of the rotary engine; 
         FIG. 2   a  is simplified, side, elevational, cross-sectional view of the two adjacent sections as shown in  FIG. 1  of the rotary engine showing an axial taper of the stator portion of the rotary engine with respect to the rotor portion of the rotary engine. 
         FIG. 3   a  is a general side, perspective view of the stator and rotor portions of a four stage version of the rotary engine of the invention; 
         FIGS. 3   b  and  3   c  are detailed side, cross-sectional and rear, end views, respectively of a rear portion of the rotary engine of  FIG. 3   a;    
         FIG. 4  is detailed, cross-sectional view of the stator portion of  FIG. 3 ; 
         FIG. 5   a  is a detailed, cross-sectional view of a portion of the ignition system of the rotary engine of the invention; 
         FIG. 5   b  is a detailed side, elevational, cross-sectional view of a portion of the ignition system of  FIG. 5   a;    
         FIG. 5   c  is a perspective, schematic view of a barber pole contact system portion of the ignition system of  FIG. 5   a;    
         FIG. 5   d  a detailed schematic view of a portion of the barber pole contact system of  FIG. 5   c;    
         FIG. 6  is a cross-sectional view of the ignition system; 
         FIGS. 7   a - 7   k  are cross-sectional plan views of the engine section of  FIG. 1  with the rotor thereof disposed at progressive positions through a combustion cycle; and 
         FIG. 8  is a timing diagram showing of one cycle (e.g., 90° of rotation) of a combustion chamber of the engine of  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The present invention provides a stackable, stationary crankshaft, cylindrical rotor, variable timing, low friction, pistonless, rotary internal combustion engine having means for venting exhaust gases and supplying coolants, lubrication, electrical power, fuel, and air to the engine. As used herein, the term stackable replies to multiple stages or layers of combustion chambers (i.e., quads), whether assembled from layers of individual quads or manufactured as a multi-stage unit. 
     In the following discussion, the engine of the invention is assumed to be in a horizontal orientation such that  FIG. 1  is an end view. However, terms such as forward and rearward are used to describe engine components relative to the direction of rotation. While the engine used for purposes of disclosure exhibits counter clockwise (CCW) rotation, it will be recognized that a clockwise (CW) rotational direction may be achieved by “mirror imaging” certain disclosed components and arrangements. Consequently, the invention includes by CW and CCW rotating engines. 
     Referring first to  FIGS. 1 and 2 , there are shown an end, elevational, cross-sectional view of one section of the rotary engine and a side, elevational, cross-sectional view of two adjacent sections of the rotary engine of the invention, generally at reference number  100 . Engine section  100  has a fixed, inner stationary portion  102  (i.e., a stator) surrounded by a concentric movable portion  104  (i.e., a rotor). The major outer diameter of stator  102  is sufficiently small such that the major inner perimeter surface of rotator  104  contacts it, but rotor  104  is free to rotate circumferentially about the major outer perimeter surface of stator  102 . In  FIG. 2 , lines  156  indicate the demarcation between stator  102  and rotor  104 . 
     A series of four circumferentially disposed combustion chambers  106 , each comprising a stationary, stator combustion chamber portion  106   a  and a rotor combustion chamber portion  106   b , are spaced equidistantly around engine section  100 . The arrangement of four circumferentially disposed combustion chambers  106  forms a so-called “quad”. While four circumferentially disposed combustion chambers  106  are shown for purposes of disclosure, it will be recognized that other numbers of circumferentially disposed combustion chambers may be used to meet a particular operating circumstance or environment. Stator combustion chamber portion  106   a  and rotor combustion chamber portion  106   b  each have a substantially triangular shape, with one or more of wall portion of each thereof optionally being curvilinear. An apex  152  is identified in a forward, outer corner of rotor combustion chamber portion  106   b.    
     A sparkplug  108  is disposed in a wall of each stator combustion chamber  106   a.    
     A fuel supply duct  110  extends from a central fuel supply chamber  114  disposed in center region of stator  102 . Central fuel supply chamber  114  is described in detail hereinbelow. Each fuel supply duct  110  terminates at the outer perimeter of stator  102  in a nozzle  112 . 
     Each rotor combustion chamber portion  106   b  has a fuel inlet port  116  disposed in an upper region thereof and communicative therewith. Fuel inlet port  116  is adapted and configured to receive fuel from nozzle  112  as fuel inlet port  116  passes nozzle  112  during rotation of rotor  104  as described in detail hereinbelow. 
     A combustion air supply chamber  118  surrounds rotor  104 . An air scoop  120  disposed on the outer periphery of rotor  104  direct air into a distal end of combustion air inlet duct  122  disposed within rotor  104 . The proximal end of air inlet duct  122  terminates in air inlet cavity  124  disposed in stator  102  proximate the inner periphery of rotor  104 . As described in detail hereinbelow, during certain periods of the rotation of rotor  104  around stator  102 , air inlet cavity  124  is communicative with venting cavity  126 , typically a small slit, disposed in stator  102 . 
     Exhaust cavity  128  is disposed in rotor  104 . Exhaust cavity  128  is connected to the proximal end of exhaust duct  130 . A distal end of exhaust duct  130  connects to exhaust ring  132  and, subsequently to exhaust pipe  134 . 
     Referring now also to  FIG. 2   a , the taper of stator  102  is illustrated. Stator  102  is shown with broken side lines  300  representing an embodiment wherein stator  102  was cylindrical (i.e., not tapered). Solid lines  302  represent the actual sides of stator  102  in a tapered embodiment having an axial taper. The distance between broken line  300  and solid line  302  is a distance  304  representative of the taper. It will be recognized that the illustration of  FIG. 2   a  is schematic and the illustrated taper is greatly exaggerated. The actual taper  304  is assumed to be in thousandths or tens of thousandths of an inch. 
     Referring now to  FIGS. 3   a  and  4 , there are shown a general side, perspective view and a detailed, cross-sectional view of a rotor and stator portions and a stator portion, respectively, of a four stage or layer version of the rotary engine  100  of the invention. In  FIGS. 3   a  and  4 , ancillary components necessary for the operation of the inventive rotary engine may be seen. A pillow block or similar support mechanism  160  secures a first, forward end of stationary hollow central shaft  162 . Typically, a pressure relief valve  192  is disposed in the forward end of stationary hollow shaft  162 . Typically, pressure relief valve  192  is frictionally engaged and adapted to pop out under an overpressure condition in the pressurized fuel system. Such valves are believed to be known to those of skill in the art and function in a manner similar to a “freeze” plug typically included in the block of a water-cooled, internal combustion engine, not shown. 
     A second, rear end of shaft  162  is secured by base  158 . A thrust bearing, not shown, disposed within base  158  provides a forward bias on stationary hollow shaft  162  to compensate for wear at the interface between stator  102  and rotor  104 . The use of thrust bearings is also believed to be known to those of skill in the art and, consequently, is not discussed in further detail herein. 
     A fuel pump  146  is disposed rearward from pillow block  160 . Fuel pump  146  receives fuel, not shown, from an external fuel reservoir, not shown, through a fuel supply line  144  and pressurizes the fuel before providing pressurized fuel directly into central fuel supply chamber  114 . In alternate embodiments, an external, typically electrically-powered, fuel pump, not shown, may be substituted for fuel pump  146 . A “slip-ring” mechanism  164 , known to those of skill in the art, may be used to pass the fuel into fuel pump  146  and/or into stationary central fuel chamber  114 . 
     An electrical generator  148  is disposed rearward of fuel pump  146 . Generator  148  has a stationary inner stator and a rotor portion, neither specifically identified, operatively attached to engine rotor  104 . Generator  148  produces an electrical current for ignition of the fuel/gas mixture in combustion chambers  106  as described in detail hereinbelow. Generator  148  may be a magneto or other type generator combined with a voltage step-up system, not shown, to provide ignition voltage to spark plugs  108  ( FIG. 1 ). The distribution of ignition voltage from generator  148  as well as a timing advance system for ensuring that combustion occurs at an optimum point in the ignition cycle is discussed in detail hereinbelow. 
     A fan  168  supported by fan bearing  166  is disposed inline behind fuel pump  146 . Fan  168  is configured to provide pressurized air to pressurized combustion air supply chamber  118  ( FIG. 1 ). 
     Referring now also to  FIGS. 3   b  and  3   c , there are shown detailed cross-sectional and rear elevational views, respectively, of common bearing base  158  disposed at the rear end of engine  100 . A rear support, not shown, supports both the fixed and rotating portions of the rear of engine  100 . Fuel Supply chamber  114  is supported by inner rear bearing  186 . Shaft  190  is the rearward extension of the rotor  104 , connected thereto by structure  202 . Shaft  190  is allowed to rotate between inner rear bearing  186  and outer rear bearing  188  and provides means for coupling the rotary output from engine  100  to an external load (e.g., a drive train), not shown. A structure  200  couples the stator to inner rear bearing  186 . A housing, not specifically identified, encloses rear support block, not specifically identified. 
     Referring now to  FIGS. 5   a ,  5   b ,  5   c ,  5   d  and  6 , there are shown detailed, cross-sectional; detailed side, elevational, cross-sectional; perspective, schematic view of a barber pole contact system; detailed schematic view of a portion of the barber pole contact system of  FIG. 5   c ; and a cross-sectional view of the electrical system, respectively. The ignition system of the inventive rotary engine derives it electrical energy from electrical generator  148 . Electrical energy from a rotating portion of electrical generator  148  is provided at a set of four contact points  172 . One contact point  172  is provided for each combustion chamber  106  ( FIG. 1 ) of engine  100  (i.e., a total of four contact points  172  in the exemplary embodiment). It will be recognized that other numbers of contact points  172  may be required for other engine configurations wherein combustion chambers  106  ( FIG. 1 ) are, is successive layers, offset at an angle, typically ranging between 45° and 90°. However, it will be recognized that other offset arrangements are possible and the invention is not limited a particular angular offset between combustion chambers in different layers or stages, not shown, of the engine. Sliding contact strips  174  are disposed to receive electrical energy from generator  148  through contact points  172 . Sliding contact strips  174  have an electrical contact  176  disposed at or near a distal end thereof. Electrical insulation  194  is disposed in several places as may be seen in  FIGS. 5   a ,  5   b ,  5   c ,  5   d  and  6 . It will be recognized that electrical insulation  194  may be a polymeric, ceramic, or another insulation type known to those of skill in the art. As the electrical insulation per se forms no part of the present invention, the invention covers any possible type of electrical insulation. 
     A set of “barber pole” contact strips  178  are disposed on and electrically insulated from an exterior surface of fuel chamber  114  (also identified as hollow, stationery shaft  162 ). The contacts strips are twisted about the cylindrical surface of fuel chamber  114  at an acute angle relative to a major axis of fuel chamber  114 . In the embodiment chosen for purposes of disclosure, an acute angle of approximately 12° has been found suitable. It will be recognized that as the twist of barber pole contact strips  178  determine the spark advance of the engine  100 , different angles may be required depending on fuel, operating conditions, and many additional factors. Consequently, the invention covers any required angle of twist. 
     Electrical conductors  180  disposed within transverse electrical channels  184  that are connected to radial spokes  182  that are, in turn, connected to barber pole contact strips  178 . Electrical conductors  180  convey electrical energy from radial spokes  182  to each layer  100  of the engine. Typically, only four barber pole contact strips  178  are required to provide requisite electrical energy to spark plugs  108  ( FIG. 1 ) at  offset combustion chambers  106  in different layers of the inventive engine. It will, however, be recognized that many other variations of combustion chamber  106  offset are possible and that the number of barber pole contracts  178  may be adjusted accordingly. A series of radial spokes  182  are connected to electrical conductors  180  which distribute electrical energy to spark plugs  108 . 
     The speed of engine  100  is also regulated by varying the amount of fuel supplied to combustion chambers  106  via nozzles  112 . Referring now again to  FIG. 4 , there is shown a cross-sectional view of several sections  102   a ,  102   b ,  102   c ,  102   d  of stator  102  of a four-section embodiment of the rotary engine of the invention. Disposed in central fuel supply chamber  114  is a valve assembly  138  that is movable along the major axis thereof. Valve assembly  138  consists of a plurality of fuel regulator sleeves  140   a ,  140   b ,  140   c ,  140   d  that selectively cover and uncover the proximal ends of fuel supply ducts  110  of respective ones of engines stator sections  102   a ,  102   b ,  102   c , and  102   d . A connecting rod  142  is rigidly attached to each of fuel regulator sleeves  140   a ,  140   b ,  140   c ,  140   d . Motion of connecting rod  142  along the major axis of central fuel supply chamber  114  as shown by arrow  150 , moves regulator sleeves  140   a ,  140   b ,  140   c ,  140   d , thereby controlling the respective areas of the proximal ends of respective ones of fuel supply ducts  110 . 
     Motion of connecting rod  142  may be effected through a linkage to a throttle control, not shown, as is well known to those of skill in the art. 
     Each regulator sleeve  140   a ,  140   b ,  140   c ,  140   d  may have a different length and/or be spaced differently along connecting rod  142 . This allows progressively feeding fuel to engine sections  100   a ,  100   b ,  100   c ,  100   d  as required for either smooth starting and acceleration or for progressively energizing engine sections when extra power is required from the engine. Typically, a front most engine section  100   a  is first energized, followed by successive sections progressively toward the rear of the engine. 
     In the engine embodiment of  FIG. 4 , four engine sections  100   a ,  100   b ,  100   c ,  100   d  are shown vertically aligned. In other words, the combustion chambers  106  ( FIG. 1 ) of each section fire at substantially the same time. It may be advantageous to offset successive engine sections so that in a multi-section engine, ignition of fuel and air occurs at different times in different engine sections (i.e., layers). This minimizes vibration and tends to reduce exhaust noise. 
     The operation of the rotary engine of the invention is now described. Referring now to  FIGS. 7   a - 7   k , there are shown a series of schematic cross-sectional views of a single stage of the novel engine  100 . The views are shown in color to clarify the movement of fuel, fresh air, and exhaust as the engine  100  rotates. Table 1 identifies the stages of a single combustion cycle of engine  100  and associates the figure associated with each stage. Note that all degrees of rotation are approximate. It will be recognized that the exact rotational sequence depends upon the fuel type and other design and application factors. Consequently, the invention is not limited to the exact rotational stages chosen for purposes of disclosure but rather covers and any and all variants thereof. 
     
       
         
               
               
               
             
           
               
                 TABLE 1 
               
               
                   
               
               
                 Degrees Rotation 
                 Action 
                 FIG. 
               
               
                   
               
             
             
               
                  0° 
                 Firing/Ignition 
                 7a 
               
               
                  2° 
                 Bleeder vent 154 opens 
                 7b 
               
               
                 15° 
                 Exhaust opens 
                 7c 
               
               
                 17° 
                 Stage 1 fresh air starts 
                 7d 
               
               
                 30° 
                 Stage 1 fresh air stops 
                 7e 
               
               
                 45° 
                 Exhaust stops 
                 7f 
               
               
                 48° 
                 Stage 2 fresh air starts 
                 7g 
               
               
                 60° 
                 Exhaust reopens 
                 7h 
               
               
                 74° 
                 Stage 2 fresh air stops 
                 7i 
               
               
                 82° 
                 Fueling begins 
                 7j 
               
               
                 88° 
                 Fueling complete 
                 7k 
               
               
                   
               
             
          
         
       
     
       FIG. 7   a  shows engine  100  in a 0° reference position. The combustion chambers  106  have previously been fully charged with a mixture of air and fuel and a spark has just been provided by spark plug  108 . The mechanism whereby an electrical signal is provided to spark plug  108  is described in detail hereinabove. 
     As a spark is provided to each charged combustion chamber  106  by sparkplug  108 , rotor  104  is impelled in a counterclockwise direction relative to  FIG. 7   a  by the resulting explosion in combustion chamber  106 . The force of the combustion is believed to be concentrated at the apex  152  (i.e., the confluence of the curved and angles walls) of rotor portion  106   b  of combustion chamber  106 . In  FIG. 7   a , combustion chamber  106  is shown in orange indicating the hot gaseous mixture therein resulting from the explosion of the fuel/air mixture ignited by spark plug  108 . As illustrated in  FIG. 7   a , rotor  104  has not yet moved relative to stator  102 . 
     Referring now to  FIG. 7   b , rotor  104  is shown advanced counterclockwise approximately 2° relative to its position in  FIG. 7   a . At this point in the rotation of rotor  104 , combustion chamber  106  is communicative with a bleeder vent  154 . Bleeder vent  154  is a small groove allowing discharge of overpressure from combustion chamber  106 . Typically, bleeder vent  154  may have an approximately 0.003 inch cross section. It should be noted, however, that this size may be changed to compensate for the fuel type or another operational parameters. Bleeder vent  154  is small enough that the majority of the explosive force caused by expanding gases within combustion chamber  106  continue to cause counterclockwise motion of rotor  104 . As seen in  FIG. 7   b , a small amount of the hot exhaust gases have started to flow into exhaust cavity  128 . 
     As shown in  FIG. 7   c , rotor  104  continues moving in a counterclockwise direction. At approximately 15° of rotation, exhaust cavity  128  becomes communicative with stator portion  106   a  of combustion chamber  106  and exhaust begins to flow through exhaust cavity  128  into exhaust duct  130  and, subsequently, into exhaust ring  132 . 
     As may be seen in  FIG. 7   d , at approximately 7° of rotation fresh air shown in green begins to flown into rotor portion  106   b  of combustion chamber  106 . Fresh air flows twice during a combustion cycle, first stage flow commencing at approximately 17°. Air from combustion air supply  118 , is directed by air scoop  120  into combustion air inlet duct  122 . Combustion air duct  122  terminates at air inlet cavity  124 . Air from air inlet cavity  124  flows into rotor portion  106   b  of combustion chamber  106 . Air entering rotor portion  106   b  of combustion chamber  106  flows into stator portion  106   a , thereby forcing exhaust gases through exhaust cavity  128  into exhaust duct  130  and purging combustion chamber  106 . 
     Because of it inertia, rotor  104  continues counterclockwise motion. As seen in  FIG. 7   e , at approximately 30° of rotation, first stage airflow stops as air inlet cavity  124  is no longer communicative with rotor portion  106   b  of combustion chamber  106 . 
     As rotation of rotor  104  continues, at approximately 45° of rotation, exhausting ceases as exhaust cavity  128  is no longer communicative with stator portion  106   a  of combustion chamber  106 . At this time, virtually all exhaust products have been purged from combustion chamber  106 . The 45° orientation is shown in  FIG. 7   f.    
     At approximately 48° rotation ( FIG. 7   g ), stage two fresh air intake begins. The fresh air now entering combustion chamber  106  will eventually be mixed with fuel to form the explosive fuel/air mixture that will be ignited by spark plug  108  at 0° rotation. Second stage fresh air inflow or charging continues until approximately 74° of rotation. 
     As shown in  FIG. 7   h , at approximately 60° of rotation, the exhaust reopens. 
     As shown in  FIG. 7   i , at approximately 74° rotation, stage two fresh air intake ceases. 
     At approximately 82° rotation ( FIG. 7   j ), fueling begins. 
     At approximately 88° ( FIG. 7   k ) fueling terminates and combustion chamber  106  is fully charged in anticipation of ignition as rotor  104  rotates to 90° or, in the foregoing description, again reaches 0°. 
     It will be recognized that additional cooling and/or lubrication systems may be required to create a functional engine. Such systems are believed to be known to those of skill in the art are not further described herein. 
     It will be further recognized that seals  196  ( FIG. 4 ) are required between successive sections or layers of the rotary engine. Seals  196  may be implemented in numerous ways known to those of skill in the art. Consequently, such seals are not further described herein. 
     The stacked sections of the rotary engine may be given a slight front-to-back taper to help maintain sealing as engine temperatures change. 
     Since other modifications and changes varied to fit particular operating requirements and environments will be apparent to those skilled in the art, the invention is not considered limited to the examples chosen for purposes of disclosure and covers all changes and modifications which do not constitute departures from the true spirit and scope of this invention. 
     Having thus described the invention, what is desired to be protected by Letters Patent is presented in the subsequently appended claims.