[0001]     This application claims the benefit of U.S. Provisional Patent Application No. 60/763,000 entitled “Apparatus, system, and method for a centrifugal turbine engine” and filed on Jan. 27, 2006 for J. Gabriel Allred, which is incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     This invention relates to internal combustion engines and more particularly relates to rotary vane engines.  
         [0004]     2. Description of the Related Art  
         [0005]     There are many types of previously known internal combustion engines. Among them are conventional piston engines in common use today. Another type of engine, the rotary engine, substitutes a rotor for pistons, producing several advantages over the conventional piston engine. These advantages include higher power to weight ratios, mechanical simplicity, and lower vibration.  
         [0006]     One type of rotary engine, the rotary vane engine, uses vanes attached to a rotor to form chambers in the engine. The vanes form seals with a housing, and as the rotor rotates, the engine generates power. The rotary vane engine shares the advantages over conventional piston engines with other types of rotary engines.  
         [0007]     Despite these advantages, rotary vane engines have not enjoyed widespread commercial success. Reasons for this lack of success include inefficiency, expensive and complicated means to urge the vanes into sealing contact with the wall defining the combustion chamber, and failure of the seals.  
       SUMMARY OF THE INVENTION  
       [0008]     From the foregoing discussion, it should be apparent that a need exists for an apparatus, system, and method for an efficient rotary vane engine. Beneficially, such an apparatus, system, and method would generate work in a manner more efficient and more reliable than existing designs.  
         [0009]     The present invention has been developed in response to the present state of the art, and in particular, in response to the problems and needs in the art that have not yet been fully solved by currently available engines. Accordingly, the present invention has been developed to provide an apparatus, system, and method for a centrifugal turbine engine that overcome many or all of the above-discussed shortcomings in the art.  
         [0010]     The apparatus for a rotary vane engine is provided including an engine block with an inner diameter, a compression ramp, and an exhaust ramp, the inner diameter defined by a raceway, the compression ramp and the exhaust ramp forming a progressively smaller raceway. The rotary vane engine may also include a rotor disposed within the engine block such that the rotor rotates within the inner diameter of the engine block. Additionally, the engine may include a plurality of vanes attached to the rotor such that the vanes retract as each vane sweeps across the compression ramp and the exhaust ramp, extend as each vane passes the compression ramp and the exhaust ramp, the extension restricted such that the vane does not contact the inner diameter of the engine block during at least a portion of a combustion stroke, and form chambers in conjunction with the engine block and the rotor that increase in volume during an intake stroke and a combustion stroke, and decrease in volume during a compression stroke and an exhaust stroke.  
         [0011]     The apparatus, in one embodiment, also includes a toroidal damper interacting with each of the plurality of vanes. The toroidal damper may comprise a mass disposed on the rotor such that the toroidal damper rotates around a damper axis and has a moment of inertia. Additionally, the toroidal damper may rotate in response to extension of the vane and resist a radial acceleration of the vane during extension in response to the moment of inertia of the toroidal damper.  
         [0012]     The apparatus is further configured, in one embodiment, such that the moment of inertia of the toroidal damper is tailored such that the rotor rotates a specific amount of rotation beyond the compression ramp before the vane extends to form an extended vane interface with the raceway. In certain embodiments, the moment of inertia of the toroidal damper is tailored such that the rotor rotates sixty degrees beyond the compression ramp before the vane extends to form an extended vane interface with the raceway.  
         [0013]     In a further embodiment, the extension of each of the plurality of vanes in the apparatus is halted by an interaction between a shoulder on the vane and a braking surface on the rotor such that the plurality of vanes are prevented from being in contact with the inner diameter of the engine block. In one embodiment of the apparatus, the interaction between the shoulder on the vane and the braking surface comprises an oil cushion formed by oil disposed on the braking surface such that the extension of the vane is decelerated by the oil cushion.  
         [0014]     In one embodiment of the apparatus, the plurality of vanes comprises three vanes. In another embodiment, the extension of each of the plurality of vanes is caused by an inertia of each of the plurality of vanes. In a further embodiment, each of the plurality of vanes further comprises a face with a curved profile, the curved profile corresponding to a curved profile of the raceway of the engine block at an extended vane interface. The apparatus may also include vanes with a friction plate disposed on an edge of each of the plurality of vanes such that the wear plate forms an interface with the engine block. The friction plate may comprise aluminized graphite. In one embodiment of the apparatus, a fuel is ignited by compression.  
         [0015]     An apparatus of the present invention is also presented for a centrifugal turbine engine. The apparatus may be embodied by an engine block with an inner diameter, a compression ramp, and an exhaust ramp, the inner diameter defined by a raceway, the compression ramp and the exhaust ramp forming a progressively smaller raceway. The apparatus may also include a rotor disposed within the engine block such that the rotor rotates within the inner diameter of the engine block. Additionally, the apparatus may include a plurality of vanes attached to the rotor such that each of the plurality of vanes retract as each vane sweeps across the compression ramp and the exhaust ramp; extend as each vane passes the compression ramp and the exhaust ramp, the extension restricted such that the vane does not contact the inner diameter of the engine block during at least a portion of a combustion stroke, wherein the extension of each vane is controlled such that the rotor rotates sixty degrees beyond the compression ramp before the vane extends to form an extended vane interface with the raceway; and form chambers in conjunction with the engine block and the rotor that increase in volume during an intake stroke and a combustion stroke, and decrease in volume during a compression stroke and an exhaust stroke.  
         [0016]     The extension of each vane in the apparatus may be controlled by a toroidal damper interacting with each of the plurality of vanes. In one embodiment, the toroidal damper comprises a mass disposed on the rotor such that the toroidal damper rotates around a damper axis and has a moment of inertia, rotates in response to extension of the vane, and resists an acceleration of the vane during extension in response to the moment of inertia of the toroidal damper.  
         [0017]     In one embodiment of the apparatus, a continuous flow of fuel is introduced into a combustion chamber. In a further embodiment, the extension of each of the plurality of vanes is caused by an inertia of each of the plurality of vanes.  
         [0018]     An apparatus of the present invention is also presented for a rotary vane engine. In one embodiment, the apparatus includes an engine block with an inner diameter, a compression ramp, and an exhaust ramp, the inner diameter defined by a raceway, the compression ramp and the exhaust ramp forming a progressively smaller raceway. The apparatus may also include a rotor disposed within the engine block such that the rotor rotates within the inner diameter of the engine block. Additionally, the apparatus may include a plurality of vanes attached to the rotor such that each of the plurality of vanes retract as each vane sweeps across the compression ramp and the exhaust ramp and extend as each vane passes the compression ramp and the exhaust ramp, the extension restricted such that the vane does not contact the inner diameter of the engine block during a combustion stroke.  
         [0019]     The extension of each vane, in one embodiment of the apparatus, is controlled by a toroidal damper interacting with each of the plurality of vanes wherein the toroidal damper comprises a mass disposed on the rotor such that the toroidal damper rotates around a damper axis and has a moment of inertia, rotates in response to extension of the vane, and resists a radial acceleration of the vane during extension in response to the moment of inertia of the toroidal damper. In one embodiment, the vanes form chambers in conjunction with the engine block and the rotor that increase in volume during an intake stroke and a combustion stroke, and decrease in volume during a compression stroke and an exhaust stroke.  
         [0020]     The moment of inertia of the toroidal damper of the apparatus also may be tailored such that the rotor rotates a specific amount of rotation beyond the compression ramp before the vane extends to form an extended vane interface with the raceway. In another embodiment, the moment of inertia of the toroidal damper is tailored such that the rotor rotates sixty degrees beyond the compression ramp before the vane extends to form an extended vane interface with the raceway. In a further embodiment, the extension of each of the plurality of vanes is caused by an inertia of each of the plurality of vanes.  
         [0021]     Reference throughout this specification to features, advantages, or similar language does not imply that all of the features and advantages that may be realized with the present invention should be or are in any single embodiment of the invention. Rather, language referring to the features and advantages is understood to mean that a specific feature, advantage, or characteristic described in connection with an embodiment is included in at least one embodiment of the present invention. Thus, discussion of the features and advantages, and similar language, throughout this specification may, but do not necessarily, refer to the same embodiment.  
         [0022]     Furthermore, the described features, advantages, and characteristics of the invention may be combined in any suitable manner in one or more embodiments. One skilled in the relevant art will recognize that the invention may be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all embodiments of the invention.  
         [0023]     These features and advantages of the present invention will become more fully apparent from the following description and appended claims, or may be learned by the practice of the invention as set forth hereinafter.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0024]     In order that the advantages of the invention will be readily understood, a more particular description of the invention briefly described above will be rendered by reference to specific embodiments that are illustrated in the appended drawings. Understanding that these drawings depict only typical embodiments of the invention and are not therefore to be considered to be limiting of its scope, the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings, in which:  
         [0025]      FIG. 1  is a side view illustrating one embodiment of an engine block in accordance with the present invention;  
         [0026]      FIG. 2  is a side view illustrating one embodiment of rotor in accordance with the present invention;  
         [0027]      FIG. 3A  is a front view illustrating one embodiment of a vane in accordance with the present invention;  
         [0028]      FIG. 3B  is a front view illustrating one embodiment of a vane in accordance with the present invention;  
         [0029]      FIG. 4  is a side view illustrating one embodiment of an engine block with an installed rotor in accordance with the present invention;  
         [0030]      FIG. 5A  is a bottom view illustrating one embodiment of an engine in accordance with the present invention;  
         [0031]      FIG. 5B  is a bottom cutaway view illustrating one embodiment of an engine in accordance with the present invention;  
         [0032]      FIG. 6  is a cross section side view illustrating one embodiment of an assembled engine in four strokes in accordance with the present invention;  
         [0033]      FIG. 7  is a cross section side view illustrating one embodiment of an assembled engine in four phases of turbine combustion in accordance with the present invention;  
         [0034]      FIG. 8A  is a side view illustrating one embodiment of a portion of a rotor with an extended vane in accordance with the present invention; and  
         [0035]      FIG. 8B  is a side view illustrating one embodiment of a portion of a rotor with a retracted vane in accordance with the present invention.  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0036]     Reference throughout this specification to “one embodiment,” “an embodiment,” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases “in one embodiment,” “in an embodiment,” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment.  
         [0037]     Furthermore, the described features, structures, or characteristics of the invention may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to provide a thorough understanding of embodiments of the invention. One skilled in the relevant art will recognize, however, that the invention may be practiced without one or more of the specific details, or with other methods, components, materials, and so forth. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of the invention.  
         [0038]      FIG. 1  illustrates one embodiment of a side view of an engine block  100  according to the present invention. The engine block  100  includes a housing  102 , a compression ramp  104 , a fuel injector  108 , an exhaust ramp  110 , an air intake port  112 , and an exhaust port  114 . The engine block  100  contains and directs gasses and fluids in an internal combustion engine.  
         [0039]     In one embodiment, the housing  102  is an annular structure that forms the outer surface of the block  100  and provides surfaces to form seals with the rotor (not shown). The housing  102  may be made from any material rigid and impermeable enough to contain the gasses in the engine, such as steel, aluminum, titanium, a composite material, or the like. In one embodiment, the housing  102  may be made from S1 steel.  
         [0040]     The housing  102 , in one embodiment, may be of any size. The power generated by the engine is related to the overall displacement of the engine, and in one embodiment, the housing  102  may be sized depending on the power needs of the engine. The housing  102  may include an inner diameter  116  at the widest portion of the housing  102 . In one embodiment, the housing  102  may have an inner diameter  116  of about ten inches.  
         [0041]     The compression ramp  104 , in one embodiment, is a curved structure that reduces the volume of a chamber as the rotor (not shown) is swept across the compression ramp  104 . The curve and height of the compression ramp  104  can be of any size within the constraints of the housing  102  and may be modified to impact the rate of compression and the compression ratio of the engine. In one embodiment, the compression ramp  104  may have a height of about two inches. In another embodiment, the compression ramp  104  may begin at a point on the housing  102  45 degrees counter clockwise from the top dead center line (TDC)  106 , a line extending from the center of the housing  102  to the top of the housing  102 .  
         [0042]     In one embodiment, the compression ramp  104  may be formed from any material rigid, strong, and impermeable enough to contain the gasses in the engine and interact with the rotor (not shown), such as steel, aluminum, titanium, a composite material, or the like. In one embodiment, the compression ramp  104  may be made from S1 steel. In an alternative embodiment, the compression ramp  104  may be formed integral with the housing  102 .  
         [0043]     The fuel injector  108 , in one embodiment, introduces fuel into the engine block  100  from outside the engine block  100 . The fuel injector  108  may meter the flow of the fuel into the engine. In one embodiment, the fuel injector may be an electronic fuel injector.  
         [0044]     As will be appreciated by one skilled in the art, a variety of fuel injectors  108  may be employed and should be considered within the scope of the present invention. For example, in an alternate embodiment, the fuel injector  108  may be a high-pressure, mechanical fuel injector. In another embodiment, the fuel injector  108  may be a venturi injector. In yet another embodiment, the fuel injector  108  may be configured to inject multiple types of fuel.  
         [0045]     The fuel injector  108 , in one embodiment, may be located near a glow plug (not shown). The glow plug increases the temperature of the fuel in the engine when the engine is starting, and allows the fuel to ignite in a compression engine when starting. In an alternative embodiment, the engine may include a spark plug (not shown) near the fuel injector  108  to ignite the fuel in the engine.  
         [0046]     In one embodiment, the exhaust ramp  110  is a curved structure that reduces the volume of a chamber as the rotor (not shown) is swept across the exhaust ramp  110 . The curve and height of the exhaust ramp  110  can be of any size within the constraints of the housing  102  and may be modified to impact the rate of exhaust expulsion of the engine. In one embodiment, the exhaust ramp  110  may have a height of about two inches. In another embodiment, the exhaust ramp  110  may end at a point about 180 degrees from TDC  106  and may begin at a point on the housing  102  about 45 degrees counter clockwise from the end of the exhaust ramp  110 .  
         [0047]     In one embodiment, the exhaust ramp  110  may be formed from any material rigid, strong, and impermeable enough to contain the gasses in the engine and interact with the rotor (not shown), such as steel, aluminum, titanium, a composite material, or the like. In one embodiment, the exhaust ramp  110  may be made from S1 steel. In an alternative embodiment, the exhaust ramp  110  may be formed integral with the housing  102 .  
         [0048]     Surfaces of the inner diameter  116 , the compression ramp  104 , and the exhaust ramp  110  may make up a raceway  118 . The raceway  118  forms a surface which interacts with vanes (not shown) to form chambers for compression, combustion, intake, and exhaust. The vanes (not shown) may sweep along the raceway  118 . The compression ramp  104  and the exhaust ramp  110  effectively form a progressively smaller diameter raceway  118   
         [0049]     The intake port  112 , in one embodiment, is a port through the housing  102  into the engine block  100 . The intake port  112  provides a pathway for air to be drawn into the engine as it operates. The intake port  112  may be sized to match the airflow requirements of the engine. The intake port  112 , in one embodiment, has a cross-sectional area equal to a vane (not shown) on the rotor (not shown). In one embodiment, the intake port  112  is a channel beginning at about 180 degrees from TDC  106  and extending to about 120 degrees counter clockwise from TDC  106 .  
         [0050]     As will be appreciated by one skilled in the art, a variety of types and configurations of intake port  112  may be utilized without departing from the scope and spirit of the present invention. For example, in one embodiment, the intake port  112  may be located in a head plate (not shown). In another embodiment, the intake port  112  may have an elliptical cross-sectional shape. In yet another embodiment, the surface of the intake port  112  may be polished to improve airflow. In a further embodiment, the intake port  112  may have a geometry optimized to create a minimum resistance to air flow.  
         [0051]     The exhaust port  114 , in one embodiment, is a port through the housing  102  into the engine block  100 . The exhaust port  114  provides a pathway for combustion gasses to be expelled from the engine as it operates. The exhaust port  114  may be sized to match the exhaust requirements of the engine. The exhaust port  114 , in one embodiment, has a cross-sectional area equal to a vane (not shown) on the rotor (not shown). In one embodiment, the exhaust port  114  is a channel beginning at about 120 degrees clockwise from TDC  106  and extending to about 180 degrees from TDC  106 .  
         [0052]     As will be appreciated by one skilled in the art, a variety of types and configurations of exhaust port  114  may be utilized without departing from the scope and spirit of the present invention. For example, in one embodiment, the exhaust port  114  may be located in a head plate (not shown). In another embodiment, the exhaust port  114  may have an elliptical cross-sectional shape. In yet another embodiment, the surface of the exhaust port  114  may be polished to improve airflow. In a further embodiment, the intake exhaust port  114  may have a geometry optimized to create a minimum resistance to air flow.  
         [0053]      FIG. 2  illustrates one embodiment of a cross-section side view of a rotor  200  according to the present invention. The rotor  200  includes a crank  202 , vanes  204 , and vane extension dampers  206 . The rotor  200  rotates within the engine block  100  in response to compressed gasses.  
         [0054]     In one embodiment, the crank  202  is sized to fit within the compression ramp  104  and the exhaust ramp  110 . The crank  202  provides a mounting platform for the other components of the rotor  200  and provides a surface which, combined with the vanes  204 , and surfaces in the block  100 , form chambers in the engine. The crank  202  rotates around a crank axis  210 . In one embodiment, the crank  202  is connected to a dive shaft (not shown) at the crank axis  210 . In another embodiment, the crank  202  is connected to a starter motor (not shown) at the crank axis  210 .  
         [0055]     In one embodiment, the crank  202  may be formed from any material rigid, strong, and impermeable enough to contain the gasses in the engine and support the other components of the rotor  200 , such as steel, aluminum, titanium, a composite material, or the like. In one embodiment, the crank  202  may be made from S1 steel.  
         [0056]     The vanes  204 , in one embodiment, provide surfaces which, in conjunction with other surfaces in the engine, form chambers in the engine. The vanes  204  are connected to the crank  202 , and rotate with the crank around the crank axis  210 . The vanes  204  have a variable amount of projection beyond the crank  202  which allows the vanes  204  to follow the contours of the raceway  118  as the crank  202  rotates. In one embodiment, the vanes  204  are arranged around the crank axis  210  at 120 degree increments.  
         [0057]     In one embodiment, the vanes  204  are disposed in tracks  212  in the crank  202 . Each vane  204  may slide within the track  212  such that the vane  204  may radially extend or retract relative to the rotor  200 . As the vane  204  retracts, it slides along the track  212  into the rotor  202 .  
         [0058]     In one embodiment, the vanes  204  extend in response to the inertia of the vanes  204 . As the rotor  200  rotates, the mass of the vanes  204  causes the vanes  204  to extend radially away from the center of the rotor  200 . This tendency for a mass to move away from a rotating body is often described as an effective force known as centrifugal force. When a vane  204  is free to slide in a track  212  while the rotor  200  is rotating, the vane will experience an effective force that causes it to extend.  
         [0059]     In one embodiment, the vanes  204  may be formed from any material rigid, strong, and impermeable enough to contain the gasses in the engine and withstand the forces generated as the engine operates, such as steel, aluminum, titanium, a composite material, or the like. In one embodiment, the vanes  204  may be made from 7% manganese titanium.  
         [0060]     In one embodiment, the rotor  200  may include one or more vane extension dampers  206 . As the crank  202  rotates, the vanes  204  are drawn across the compression ramp  104  and the exhaust ramp  110 . As the vanes  204  transit the ramps  104 ,  110 , they are compressed. When the vanes  204  pass the ramps  104 ,  110 , they are free to extend to their full length. The vane extension dampers  206  control the rate extension of the vanes  204  by resisting the radial acceleration of the vanes  204 .  
         [0061]     In one embodiment, the vane extension dampers  206  are toroidal bodies that rotate around a damper axis  208 . The dampers  206  interact with the vane  204  such that the damper  206  rotates as the vane  204  slides relative to the track  212 . In one embodiment, the damper  206  has gear teeth that mesh with similar gear teeth on the vane  204 . In another embodiment, the damper  206  is in contact with the vane  204  and is driven by friction as the vane  204  moves relative to the track  212 .  
         [0062]     The damper  206 , in one embodiment, has a rotational inertia relative to its physical characteristics, such as its shape and distribution of mass within that shape known as a moment of inertia. The moment of inertia of the damper  206  can be tailored to control the rate of extension of the vane  204  as the rotor  200  rotates within the block  100 .  
         [0063]     In one embodiment, as a compressed vane  204  rotates, the inertia of the vane  204  will cause it to extend. As the angular velocity of the rotor  200  increases, the tendency of the vane  204  to extend will also increase. In one embodiment, the damper  206  exerts a force on the vane  204  resisting radial acceleration of the vane  204  that increases as the rate of radial acceleration of the vane  204  increases. In another embodiment, the moment of inertia of the damper  206  can be tailored such that the vane  204  reaches full extension at a specified amount of rotation past TDC  106  at any operational rotational speed of the rotor  200 . In one embodiment, the damper  206  is tailored to cause the vane  204  to reach full extension at 60 degrees past TDC  106  and 240 degrees past TDC  106 .  
         [0064]     As will be appreciated by one skilled in the art, a variety of configurations and types of vane extension damper  206  may be employed without departing from the scope and spirit of the present invention. For example, a hydraulic damper  206  may be employed that links the extension of one or more vanes  204  to the retraction of one or more vanes  204  such that the net extension or retraction among all the vanes  204  is zero. In another embodiment, the vane extension dampers  206  may comprise air springs linked to the vanes  204  that control the rate of extension. In another embodiment, the dampers  206  may comprise springs that are linked to the vanes that exert force on the vanes  204  that resist extension.  
         [0065]      FIG. 3A  illustrates one embodiment of a front view of a vane  204  according to the present invention. The vane  204  is preferably configured in a manner similar to a like number component in relation to  FIG. 2 . The vane  204  includes a face  302 , one or more friction plates  304 , a vane extension damper interface  306 , and a shoulder  308 . The vane  204  moves as described in  FIG. 2  relative to the crank  202  as the rotor  200  rotates.  
         [0066]     In one embodiment, the face  302  acts as a wall of a chamber in the engine and provides a foundation for the friction plates  304  and the vane extension damper interface  306 . The face  302  may be formed from any material rigid, strong, and impermeable enough to contain the gasses in the engine and withstand the forces generated as the engine operates, such as steel, aluminum, titanium, a composite material, or the like. In one embodiment, the face  302  may be made from 7% manganese titanium.  
         [0067]     The friction plate  304 , in one embodiment, forms the interface between the vane  204  and the engine block  100 . As the rotor  200  rotates, the vanes  204  may interact with the engine block &#39; 00  and produce friction. This friction produces heat and causes wear.  
         [0068]     The friction plate  304 , in one embodiment, is made of a material that reduces wear on the engine block  100 . In another embodiment, the friction plate  304  is made of a material that resists wear on the friction plate  304 . In a further embodiment the friction plate  304  is made of a material that reduces the friction between the friction plate  304  and the engine block  100 .  
         [0069]     The friction plate  304 , in one embodiment, may be formed from any material that has the physical characteristics required to produce the desired effect on the friction between the vane  204  and the head plate, such as steel, aluminum, titanium, a composite material, or the like. In one embodiment, the friction plate  304  may be made from M1 steel. In another embodiment, the friction plate  310  may be made from M2 steel. In an alternate embodiment, the friction plate  304  may be made from aluminized graphite.  
         [0070]     The vane extension damper interface  306 , in one embodiment, interacts with the vane extension damper  206  to exert a force that resists extension of the vane  204 . In one embodiment, the vane extension damper interface  306  comprises a row of gear teeth that mate with gear teeth on the damper  206 . In another embodiment, the vane extension damper interface  306  comprises more than one row of gear teeth that mate with gear teeth on the damper  206 . In yet another embodiment, the vane extension damper interface  306  comprises a surface that interacts with the damper  206  through friction.  
         [0071]     The shoulder  308 , in one embodiment, interacts with a braking surface (not shown) on the rotor  200  to halt the extension of the vane  204 . The shoulder  308  may comprise an area of the vane  204  that extends beyond the area of the face  302 . In one embodiment, the shoulder  308  may be cast with the vane  204  or machined from a single piece of material with the vane  204 . In an alternate embodiment, the shoulder  308  may be  
         [0072]      FIG. 3B  illustrates another embodiment of a front view of a vane  204  according to the present invention. The vane  204  includes a face  302 , a friction plate  310 , a vane extension damper interface  306 , a shoulder  308 , and a curved profile  312 . The vane  204 , extension damper interface  306 , and shoulder  308  are preferably configured in a manner similar to like number components in relation to  FIG. 3A . The vane  204  moves as described in  FIG. 2  relative to the crank  202  as the rotor  200  rotates.  
         [0073]     The face  302 , in one embodiment, acts as a wall of a chamber in the engine and provides a foundation for the friction plate  310  and the vane extension damper interface  306 . The face  302  may be formed from any material rigid, strong, and impermeable enough to contain the gasses in the engine and withstand the forces generated as the engine operates, such as steel, aluminum, titanium, a composite material, or the like. In one embodiment, the face  302  may be made from 7% manganese titanium. The face  302  may include a curved profile  312 . The curved profile  312  may correspond to a curved profile (not shown) of the raceway  118  to form an extended vane interface.  
         [0074]     In one embodiment, the friction plate  310  is disposed around the edge of the face  302  of the vane  204 . The friction plate  310  forms the closest point to the raceway  118  during operation of the engine and acts to reduce friction and wear between the vane  204  and the engine block  100 . The friction plate  310  may form an interface with the engine block  100 .  
         [0075]     The friction plate  310 , in one embodiment, may be formed from any material that has the physical characteristics required to produce the desired effect on the friction between the vane  204  and the head plate, such as steel, aluminum, titanium, a composite material, or the like. In one embodiment, the friction plate  310  may be made from M1 steel. In another embodiment, the friction plate  310  may be made from M2 steel. In an alternate embodiment, the friction plate  310  may be made from aluminized graphite.  
         [0076]      FIG. 4  illustrates one embodiment of an engine block  100  with an installed rotor  200 . The engine block  100  is preferably configured in a manner similar to a like numbered component in relation to  FIG. 1 , and the rotor  200  is preferably configured in a manner similar to a like numbered component in relation to  FIG. 2 . The rotor  200  rotates in a clockwise direction within the block  100  as indicated by the arrow  402 . The installed rotor  200  may include a compression ramp interface  404 , an extended vane interface  406 , an exhaust ramp interface  408 , and a gas check port  414 .  
         [0077]     In one embodiment, the compression ramp interface  404  allows compressed air to pass from a compression chamber to a combustion chamber while resisting the flow of gas from the combustion chamber into the compression chamber. In one embodiment, the compression ramp interface  404  is a gap between the crank  202  and the compression ramp  104  sized allow compressed air to pass into the combustion chamber while resisting the flow of combustion gasses in the opposite direction through the effect of turbulence. In one embodiment, the compression ramp interface  404  is a 0.3 inch gap between the crank  202  and the compression ramp  104 .  
         [0078]     The extended vane interface  406 , in one embodiment, forms a seal between an extended vane  204  and the inner diameters  16  of the engine block  100 . The seal between the extended vanes  204  and the inner diameter  116  allows the expanding gas in the compression chamber to rotate the rotor  200  and also causes the rotating rotor  200  to expel exhaust, draw in air through the intake, and compress air.  
         [0079]     In one embodiment, the extended vane  204  does not contact the inner diameter  116 , but forms a seal by leaving a small gap between the vane  204  and the housing  102 . The gap at the extended vane interface  406  is sized such that gas flowing through the gap generates turbulence that resists rapid flow of the gas. In another embodiment, the vane contacts the inner diameter  116  at the extended vane interface  406  to form a seal.  
         [0080]     The exhaust ramp interface  408 , in one embodiment, resists the flow of gas past the interface  408 , causing exhaust gas to be expelled through the exhaust port  114  and air to be drawn in through the intake  112 . In one embodiment, the exhaust ramp interface  408  is a gap between the crank  202  and the exhaust ramp  110  sized such that gas flowing through the gap generates turbulence that resists rapid flow of the gas. The gap at the exhaust ramp interface  408  is one eighth of an inch in one embodiment.  
         [0081]     The rotor  200  may include a plurality of vanes  204  and tracks  212 . The vanes  204  may slide within the tracks  212  to allow each of the vanes  204  to radially extend and retract relative to the rotor  200 . In one embodiment, the extension of a vane  204  may be halted by an interaction between the shoulder  308  of the vane  204  and a braking surface  410  on the rotor  200 . The braking surface  410  may comprise a portion of the track  212  that is narrower than the shoulder  308 , but wide enough to allow the body  302  of the vane  204  to slide through the track  212 . As a result, the vane  204  will extend freely until the shoulder  308  interacts with the braking surface  310 .  
         [0082]     In one embodiment, the braking surface  310  is positioned on the rotor  200  such that the extension of the vane  204  is halted such the vane  204  does not come in contact with the inner diameter  116  of the engine block  100 . The vane  204  may leave a gap at the extended vane interface  406  when the shoulder  308  interacts with the braking surface  410 .  
         [0083]     The braking surface  410 , in one embodiment, may include an oil cushion  412  at the braking surface  410 . The oil cushion  412  is formed by oil disposed on the braking surface  410 . As the shoulder  308  approaches the braking surface  410 , the shoulder  308  interacts with the oil cushion  412 , decelerating the extension of the vane  204 . In one embodiment, the oil cushion  412  may be disposed in a reservoir located on the braking surface  410 . The oil in the oil cushion  412  may be supplied by an oil galley in the crank  202 .  
         [0084]     The gas check port  414 , in one embodiment, allows gasses to flow into the track  212  to generate a pressure in the track  212 . The gas check port  414  may comprise a check valve that allows high-pressure combustion gas in the combustion chamber to enter the track  212 . The gas check port  414  may be disposed on the outer surface of the crank  202  such that as the rotor  200  rotates, the check port passes through areas with relative high pressure gasses and relatively low pressure gasses. In one embodiment, the rotor  200  includes a gas check port  414  between every pair of vanes  204 . In another embodiment, the gas check port  414  may enter the combustion chamber when a vane  204  has swept sixty degrees beyond the compression ramp  104 .  
         [0085]     The high pressure gas may be delivered from the gas check port  414  to the track through a channel  416 . The channel may be cast into the crank  202 . In an alternate embodiment, the channel  416  may be machined into the crank  202 .  
         [0086]     The pressure created in the track  212  by the gas check port  414  results in a force causing the vanes  204  to extend when the pressure in the track  212  exceeds the pressure surrounding the vane  204 . As a result, when the vane  204  is in a relatively low pressure area of the engine  100 , the pressure assists in extending the vane  204 . When the vane  204  is in a relatively high pressure area, such as the combustion chamber, the net pressure on the vane  204  may be neutral or it may result in a force resisting extension. Even when the net pressure resists extension, by allowing pressure into the track  212 , the gas check valve  414  reduces the overall pressure differential, and limits the amount of force resisting extension due to pressure.  
         [0087]      FIG. 5A  is a bottom view illustrating one embodiment of an engine  500 . The engine  500  includes a block  100  with an intake port  112  and an exhaust port  114 , a head plate  502 , and a drive shaft  504 . The block  100 , intake port  112  and exhaust port  114  are preferably configured in a manner similar to like numbered components described in relation to  FIG. 1 .  
         [0088]     In one embodiment, the head plate  502  attaches to the block  100  and interacts with the block  100  and the rotor  200  to form chambers. The head plate  502 , in one embodiment, comprises a disc with a central hole for the drive shaft  504 . The head plate may be attached to the block  100  by fasteners, such as bolts or the like, by a weld, by clips, or by other like devices.  
         [0089]     The head plate  502  may be formed from any material rigid, strong, and impermeable enough to contain the gasses in the engine and withstand the forces generated as the engine operates, such as steel, aluminum, titanium, a composite material, or the like. In one embodiment, the head plate  502  may be made from S1 steel.  
         [0090]     In one embodiment, the engine  500  includes two head plates  502  mounted on opposite sides of the block  100 . In one embodiment, both head plates  502  include a hole for a drive shaft  504 . In an alternate embodiment, one head plate  504  does not include a hole for a drive shaft. The head plate  502 , in one embodiment, includes raised vanes on the outer surface to dissipate heat.  
         [0091]     The drive shaft  504 , in one embodiment, connects to the rotor  200  as described in relation to  FIG. 2 . The drive shaft  504  transfers the power generated as the rotor  200  rotates to components outside of the engine  500 . In one embodiment, a drive shaft  504  extends from only one side of the engine  500 . In another embodiment, a drive shaft  504  extends through both head plates  502  to both sides of the engine  500 .  
         [0092]     In one embodiment, the drive shaft  504  is connected to a starter motor (not shown) as described in relation to  FIG. 2 . In another embodiment, a drive shaft  504  is connected to a drive shaft of another engine (not shown) for operation in series to generate more power.  
         [0093]     The drive shaft  504  may be formed from any material rigid and strong enough to withstand the forces generated as the engine operates, such as steel, aluminum, titanium, a composite material, or the like. In one embodiment, the drive shaft  504  may be made from S1 steel.  
         [0094]      FIG. 5B  is a bottom cutaway view illustrating one embodiment of an engine  506 . The engine  506  includes a two-piece block  508 ,  510 , an exhaust port  114 , a vane  204  with a curved profile  312 , a rotor  200 , and a drive shaft  504 . An intake port (not shown) is located in the portion of the two-piece block  508 ,  510  removed by the cutaway. The exhaust port  114  and the drive shaft  504  are preferably configured in a manner similar to like numbered components in relation to  FIG. 5A . The rotor  200  is preferably configured in a manner similar to a like numbered component in relation to  FIG. 4 . The vane  204  with a curved profile  312  is preferably configured in a manner similar to a like numbered component in relation to  FIG. 3 .  
         [0095]     The two-piece block  508 ,  510  contains and directs fluids and gasses in the engine  506 . In one embodiment, the two piece block  508 ,  510  may have a curved profile  512  corresponding to the curved profile  312  of the vane  204 . The curved profile  512  and the two-piece block  508 ,  510  simplify manufacture of the engine  506  and eliminate stress concentration points caused by angles.  
         [0096]     In one embodiment, the two-piece block  508 ,  510  interacts with the vanes  204  and the rotor  200  to form chambers. The two-piece block  508 ,  510 , in one embodiment, includes a central hole for the drive shaft  504 . The two-piece block  508 ,  510  may be secured together by fasteners, such as bolts or the like, by a weld, by clips, or by other like devices.  
         [0097]     The two-piece block  508 ,  510  may be formed from any material rigid, strong, and impermeable enough to contain the gasses in the engine and withstand the forces generated as the engine operates, such as steel, aluminum, titanium, a composite material, or the like. In one embodiment, the two-piece block  508 ,  510  may be made from S1 steel.  
         [0098]     In one embodiment, the two-piece block  508 ,  510  includes a hole for a drive shaft  504  on opposite sides of the two-piece block  508 ,  510 . In an alternate embodiment, the two-piece block  508 ,  510  includes only one hole for a drive shaft. The two-piece block  508 ,  510 , in one embodiment, includes raised vanes on the outer surface to dissipate heat.  
         [0099]      FIG. 6  is a cross section side view illustrating one embodiment of an assembled engine in four strokes, including an intake stroke ( FIG. 6A ), a compression stroke ( FIG. 6B ), a combustion stroke ( FIG. 6C ), and an exhaust stroke ( FIG. 6D ). The engine progresses through the four strokes illustrated, then repeats the cycle. The illustrations in  FIG. 6  include an engine block  100  and a rotor  200 , which are preferably configured similarly to like numbered components described in relation to  FIG. 4 .  
         [0100]      FIG. 6A  illustrates one embodiment of an intake stroke. As the rotor  200  rotates, a vane  204  sweeps along the raceway  118 , increasing the volume of an intake chamber  602 . As the volume of the intake chamber  602  increases, the pressure in the chamber  602  decreases. The decreased pressure in the chamber  602  causes air to be drawn through the intake port  112  and into the intake chamber  602 .  
         [0101]      FIG. 6B  illustrates one embodiment of a compression stroke. As the rotor  200  rotates, a vane  204  sweeps along the raceway  118  and up the compression ramp  104 , decreasing the volume of a compression chamber  604 . As the volume of the compression chamber  604  decreases, the pressure in the chamber  604  increases. The ratio of the volume of the chamber  604  at the beginning of compression to the end of compression (the compression ratio) can be tailored to meet the performance needs of the engine, as described in relation to  FIG. 1 . In certain embodiments, at high engine speeds the temperature in the compression chamber  604  increases dramatically as the volume of the compression chamber  604  decreases. The increased temperature results in an increased pressure in the compression chamber  604 , leading to a higher compression ratio. In one embodiment, the compression ratio is 50:1.  
         [0102]      FIG. 6C  illustrates one embodiment of a combustion stroke. As the rotor  200  rotates, compressed air passes through the compression ramp interface  404  into a combustion chamber  606 . The fuel injector  108  mixes fuel with the compressed air in the combustion chamber  606 . In one embodiment, the fuel in the combustion chamber  606  ignites in response to the pressure in the combustion chamber  606 . In an alternate embodiment, the fuel in the combustion chamber  606  is ignited by a spark plug (not shown).  
         [0103]     When the fuel air mixture ignites in the combustion chamber  606 , the pressure of the gas in the combustion chamber  606  increases. The increased pressure generates a force on the vane  204 , causing the rotor  200  to rotate.  
         [0104]     In one embodiment, the vane  204  does not contact the housing  102  during the combustion stroke. The extension of the vane  204  may be restricted such that a small gap remains between the vane  204  and the housing  102 . In one embodiment, a seal between the vane  204  and the housing  102  is created through turbulent flow effects as the combustion gas attempts to flow through the gap into an exhaust chamber  608 .  
         [0105]      FIG. 6D  illustrates one embodiment of an exhaust stroke. As the rotor  200  rotates, a vane  204  sweeps along the raceway  118  and up the exhaust ramp  110 , decreasing the volume of the exhaust chamber  608 . As the volume of the exhaust chamber  608  decreases, exhaust gasses in the exhaust chamber  608  are forced through the exhaust port  114 .  
         [0106]      FIG. 7  is a cross section side view illustrating one embodiment of an assembled engine at four sequential moments of turbine combustion in accordance with the present invention, including the beginning of a main expansion phase ( FIG. 7A ), the end of the main expansion phase ( FIG. 7B ), the beginning of a transition phase ( FIG. 7C ), and the end of the transition phase ( FIG. 7D ). The illustrations in  FIG. 7  include an engine block  100  and a rotor  200 , which are preferably configured similarly to like numbered components described in relation to  FIG. 6 . In turbine combustion, the fuel injector  108  injects a continuous stream of fuel into a combustion chamber  606 , and ignition of the fuel air mix in the combustion chamber  606  is continuous.  
         [0107]      FIG. 7A  illustrates one embodiment of the start of the main expansion phase, which begins when a first vane  702  reaches full extension and forms an interface with the raceway  118  at the extended vane interface  406 . In one embodiment, the first vane  702  reaches full extension at 60 degrees past TDC  106 . Combustion in the combustion chamber  606  occurs continuously as the engine operates, and gasses generated by combustion increase the pressure in the combustion chamber  606 . The increased pressure exerts a force  704  on the first vane  702  which causes the rotor  200  to rotate.  
         [0108]      FIG. 7B  illustrates one embodiment of the end of the main expansion phase, which occurs when the first vane  702  reaches the exhaust port  114 . Combustion in the combustion chamber  606  occurs continuously as the engine operates, and gasses generated by combustion increase the pressure in the combustion chamber  606 . The increased pressure exerts a force  704  on the first vane  702  which causes the rotor  200  to rotate.  
         [0109]      FIG. 7C  illustrates one embodiment of the transition phase, which begins as the first vane  702  passes the exhaust port  114 . Combustion in the combustion chamber  606  occurs continuously as the engine operates, and gasses generated by combustion increase the pressure in the combustion chamber  606 . During the transition phase, there may be an open pathway to the exhaust port  114  from the combustion chamber  606 , since a following vane  706  may not have extended completely to form an interface with the housing  102  at the extended vane interface  406 .  
         [0110]     During the transition period, the expanding gasses in the combustion chamber  606  flow toward the exhaust port  114 . As the gasses flow toward the exhaust port  114 , they create turbulence that generates a force  708  on the partially extended following vane  706  and continue to apply a force  704  on the first vane  702 .  
         [0111]      FIG. 7D  illustrates one embodiment of the end of the transition phase, which occurs when the following vane  706  reaches full extension and forms an interface with the raceway  118  at the extended vane interface  406 . In one embodiment, the following vane  706  reaches full extension at 60 degrees past TDC  106 . At the end of the transition phase, the main expansion phase begins as illustrated by  FIG. 7A , and the cycle repeats.  
         [0112]      FIG. 8  is a side view of one embodiment of a portion of a rotor  200  illustrating a damper  206  with an eccentric mass  802 . The damper  206  with an eccentric mass  802  interacts with the vane  204  as the rotor  200  rotates to decelerate the extension and retraction of the vane  204  as the vane approaches the limits of its travel.  
         [0113]      FIG. 8A  illustrates the vane  204  at full extension. In one embodiment, as the vane  204  approaches full extension, the damper  206  rotates, moving the eccentric mass  802  to a position on the opposite side of the damper axis  208  from the vane  204 . The rotation of the rotor  200  generates an effective force known as centrifugal force on masses rotating with the rotor  200 . The centrifugal force  804  acting on the eccentric mass  802  generates a moment  806  on the damper  206  that varies as the damper  206  rotates in response to the extension and retraction of the vane  204 . The moment  806  increases as the distance between the eccentric mass  802  and a line drawn from the center of the rotor  200  through the damper axis  208  increases.  
         [0114]     When the vane  204  approaches full extension, the eccentric mass  802  generates a moment  806  that resists the extension of the vane  204 . In one embodiment, the moment  806  increases as the vane  204  approaches full extension. As illustrated in  FIG. 8A , in one embodiment the eccentric mass  802  rotates to a point that generates a maximum moment  806  at full extension of the vane  204 .  
         [0115]      FIG. 8B  illustrates the vane  204  at full retraction. In one embodiment, as the vane  204  approaches full retraction, the damper  206  rotates, moving the eccentric mass  802  to a position on the side of the damper axis  208  nearest the vane  204 . The centrifugal force  804  acting on the eccentric mass  802  generates a moment  806  on the damper  206  that varies as the damper  206  rotates in response to the extension and retraction of the vane  204 . The moment  806  increases as the distance between the eccentric mass  802  and a line drawn from the center of the rotor  200  through the damper axis  208  increases.  
         [0116]     When the vane  204  approaches full retraction, the eccentric mass  802  generates a moment  806  that resists the retraction of the vane  204 . In one embodiment, the moment  806  increases as the vane  204  approaches full retraction. As illustrated in  FIG. 8B , in one embodiment the eccentric mass  802  rotates to a point that generates a maximum moment  806  at full retraction of the vane  204 .  
         [0117]     In one embodiment, the damper  206  has a circumference equal to twice the distance that the vane  204  travels between full retraction and full extension. As a result, the damper  206  rotates 180 degrees as the vane  204  travels between full extension and full retraction. In another embodiment, each vane  204  has two dampers  206  on opposite sides of the vane  204 . In an alternate embodiment, the damper  206  includes a stop that halts the rotation of the damper  206  as the vane  204  reaches full retraction.  
         [0118]     The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.
An apparatus, system, and method are disclosed for a centrifugal turbine engine. The engine includes an engine block with a raceway comprising an inner diameter, a compression ramp, and an exhaust ramp and a rotor disposed within the engine block such that the rotor rotates within the inner diameter of the engine block. The rotor includes a plurality of vanes attached to the rotor such that the vanes retract as each vane sweeps across the compression ramp and the exhaust ramp and extend as each vane passes the compression ramp and the exhaust ramp. The extension is restricted such that the vane does not contact the inner diameter of the engine block during at least a portion of a combustion stroke. Beneficially, the engine is more efficient and reliable than existing engines.