Abstract:
The present invention comprises, in one embodiment, an inexpensive, lightweight flying vehicle using fixed pitch helicopter blades powered by ramjet engines mounted to a power-ring which transfers torque to the lifting rotors. The use of fixed pitch blades eliminates the need for a tail boom and tail rotor, as well as for variable incidence control of blade pitch and/or cyclic and collective rotor-pitch controls. An optional ballistic parachute may be deployed for emergency landings. A radial shroud encloses the ramjet engines to act as a sound shield. Since the rotor has a fixed pitch, lift may be controlled by rotor speed, where increased speed results in ascent, and decreased speed, descent.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application claims priority from Provisional U.S. Patent Application No. 60/910,843 filed on Apr. 10, 2007, and incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to helicopters and rotary wing vertical flight aircraft. In particular, the present invention is directed toward a rotary wing vertical flight aircraft using ramjets or other thrust devices mounted on a power ring, which transfers torque to the lifting rotors. 
     BACKGROUND OF THE INVENTION 
     A number of helicopters and rotorcraft using ramjets or the like, mounted on the tips of the rotors, are known in the art. Probably the most famous and most operable of these was the American Helicopter XA-8/XH-26 “Flying Jeep” aircraft. The Model XA-8 single-seat lightweight helicopter was a light, collapsible machine, which could be used as both a light observation craft and as an air-droppable rescue vehicle for downed aircrew. The XH-26 was powered by two pulse-jet engines, one fixed to the tip of each main rotor blade, and could burn virtually any type of fuel. Another novel feature of this aircraft was the use of a single-bladed, counterbalanced tail-rotor (presumably for packaging reasons). The Army and Air Force jointly evaluated the five XH-26 prototypes from 1952 to 1954. The machines were found to be robust in construction and relatively simple to operate, but neither service procured the type in quantity. One problem noted by users was that the pulse-jet engines were quite loud when in use, and the aircraft exhibited a “screaming” noise when in use. 
     Other helicopters using thrust engines on rotor tips as well as air jets and other devices are known in the art. The following Patents and published Patent Applications, all incorporated herein by reference, were discovered in a Prior Art search commissioned by Applicant. 
     U.S. Pat. No. 3,417,825, entitled “HELICOPTER ROTOR AND TURBINE ASSEMBLY” (RAMME) discloses a helicopter with counter rotating rotor blades that are driven by jet engine exhaust. Thus device, rather that using wing-tip pulse-jets, uses a rather cumbersome radial turbine mounted to the blade. Note the lack of tail rotor. The device does appear to use a pitch and cycle control. 
     U.S. Pat. No. 4,589,611, entitled “Air jet reaction contrarotating rotor gyrodyne” (RAMME) discloses a contra-rotating rotor gyro-dyne which has twin turbofan engines providing forward jet thrust with a bypass air fraction for rotating rotors. This design uses jet exhaust ducted into the tips of counter-rotating rotors. See FIG. 3. The design appears to use a pitch control. See FIG. 6. The apparatus appears to be directed more toward a gyrocopter design than a helicopter. 
     U.S. Pat. No. 3,176,413 (DORNIER) discloses a helicopter with a jet-tip type propulsion system. This apparatus is disclosed as a “training apparatus” rather than as a flyable helicopter. The design does show the use of wing-tip jet engines. 
     U.S. Pat. No. 2,437,700 (MACFARLAND, JR.) discloses a dual rotor helicopter with reaction motor propulsion. This design uses rotating jets, but they are not attached to the wing tips, but rather to a separate boom. A gearbox transmits this energy to counter-rotating rotor blades. 
     U.S. Pat. No. 2,509,359 (MARGOLIS) discloses a rotary reaction motor. This reference broadly teaches the concept of using a pulse-type jet to power a propeller. Note how the jet angle may be changed to alter thrust. 
     U.S. Pat. No. 2,710,067 (SFORZN) discloses a rotorcraft with rotor tip propulsion. This reference also teaches the use of a wingtip jet rotor using an engine driven compressor. Note the lack of counter-rotating rotors, however. 
     U.S. Pat. No. 2,594,788 (MORAIN) discloses a blade tip propulsion system. This reference is directed toward solving one of the detailed problems in providing fuel to rotor-tip mounted engines. 
     U.S. Pat. No. 3,371,718, entitled “ROTARY JET REACTION MOTORS,” (BACON) discloses a rotary jet reaction motor for wing blades. This reference also teaches the use of wing-tip mounted jets. Note the pitch control gears in FIG. 2. 
     U.S. Pat. No. 3,699,771, entitled “ROTARY WING AIRCRAFT LIFT AND PROPULSION METHOD AND SYSTEMS” (CHELMINSKI) discloses a rotary wing aircraft lift and propulsion method and system in which burner thruster units mounted on the lift-producing rotor at a position spaced radially from the axis of the rotor generate moments to turn the rotor about its axis. This reference also teaches the use of wing-tip mounted jets in a single rotor configuration. 
     Published U.S. Patent Application 20040000614A1 entitled “Method and apparatus for lifting and propelling rotorcraft (LEYVA) discloses a lifting and propelling apparatus for a rotorcraft, which has pulse detonation engines, which impulsively detonate fuel-air mixtures to generate and apply thrust forces to rotor assembly. This recent reference to GE Research shows the use of a jet mounted to the HUB of the rotor (FIG. 2), the rotor itself (FIG. 3) and within the rotor (FIG. 4). A pulse detonation engine is described. 
     U.S. Pat. No. 3,930,625 (KRIVKA) discloses a steam jet powered helicopter, which has shroud surrounding blade nozzles to condense and recycle steam. See FIG. 9. See paragraph at column 5, line 57 for description of FIG. 9. 
     U.S. Pat. No. 5,149,014, entitled “Rotary wing aircraft” (FALLER) discloses a rotation compensated helicopter drive, which incorporates hollow blades and compressed air ducted to exit slots from central turbine. 
     U.S. Pat. No. 5,984,635, entitled “Keller pressure jet rotor system” (KELLER) discloses a pressure jet rotor system in helicopters. 
     U.S. Pat. No. 3,768,926, entitled “PULSE JET ROTOR DRIVE FOR HELICOPTER” (PEGG) discloses a pulse-jet system for driving a rotary wing aircraft. In a first embodiment the tips of the rotors of a rotary wing aircraft are provided with “U”-shaped valveless pulse jet engines having an annular scoop adjacent to the lip of the inlet to provide fresh air thereto at increased air velocity. 
     U.S. Pat. No. 6,390,413, entitled “Years two thousand of new safety helicopter” (CHIU) discloses a system for landing a falling helicopter in an accident with at least one parachute mounted on the helicopter, and speed reduction jets mounted at belly portion of helicopter. 
     U.S. Pat. No. 3,873,049, entitled “Flying machine” (HORSDAL) discloses a VTOL flying machine with four rotors producing upward thrust with rotor slots to provide forward thrust. 
     U.S. Pat. No. 5,791,592, entitled “Helicopter with coaxial counter-rotating dual rotors and no tail rotor” (NOLAN) discloses a helicopter with coaxial counter rotating dual rotors and no tail rotor. A pair of engines drive a single rotating shaft on which a pair of rotors are mounted. 
     U.S. Pat. No. 3,722,830, entitled “HELICOPTER TYPE VEHICLE” (BARBER) discloses a helicopter type vehicle having coaxial counter rotating propellers above the cabin of the vehicle, each propeller being fixed in pitch as opposed to conventional helicopter propellers which vary in pitch during rotation of the propeller. 
     U.S. Pat. No. 3,610,555, entitled “FLUID-DRIVEN ROTARY WING AIRCRAFT” (NAGLER) discloses a rotary wing aircraft which operates during takeoff and landing as a conventional helicopter employing the combined outputs of main and auxiliary compressors. 
     U.S. Pat. No. 6,216,446, entitled “Valveless pulse-jet engine with forward facing intake duct” (STRAM) discloses a self-starting, self-spirating valveless jet engine which has a supersonic fuel nozzle fitted into the vaporizer tube, positioned in front and to the center of the flared mouth of the first stage intake duct. 
     Published U.S. Patent Application 20020125368A1, entitled “Ultralight coaxial rotor aircraft” (PHELPS) discloses an ultra-light coaxial dual rotor helicopter includes air-inflated pontoon skids, pitch and roll control by actuators tilting the rotor axis, and yaw control paddles. 
     U.S. Pat. No. 5,370,341, entitled “Ultralight helicopter and control system” (LEON) discloses an ultra-light helicopter and control system with a single motor drive for counter-rotating rotors via a bevel gearing or hydraulic pump-motors. 
     U.S. Pat. No. 1,133,660 (PAPIN) discloses a helicopter with air that pushes out of rotor tips. 
     U.S. Pat. No. 2,831,543 (MATTHEWS) discloses a helicopter with jet pressure driven rotors. 
     SUMMARY OF THE INVENTION 
     The present invention comprises, in one embodiment, an inexpensive, lightweight flying vehicle using counter-rotating fixed pitch lifting blades powered by ram jet engines mounted to a power-ring, which transfers torque to the lifting rotor. The use of counter-rotating fixed pitch lifting blades eliminates the need for a tail boom and tail rotor, as well as for variable incidence control of blade pitch and/or cyclic and collective rotor-pitch controls. An optional ballistic parachute may be deployed for emergency landings. A radial shroud encloses the ram jet engines to act as a sound shield and to supply air to the power ring jet engines. Since the rotors have a fixed pitch, lift may be controlled by rotor speed, where increased speed results in ascent, and decreased speed, descent. 
     In the preferred embodiment, the flying vehicle is power-lifted by ramjet engines in a gyro configuration. The ramjets may comprise two or more engines on a power ring configuration running at a high RPM to produce high-powered torque. This torque is then transferred to the torque configuration where a fixed-pitch lifting rotor is located. Directional control is achieved by tilting the core controller torque configuration. To go forward, the user “tilts” forward. To go right, the user “tilts” right. To go left, the user “tilts” left. To go backward, the user “tilts” backward. 
     Struts are used to support the soundproofing shroud. In the power-ring embodiment, the power-ring is not attached to the shroud, but rather runs in the shroud. Similarly, the lifting rotor is not attached to the shroud, but are running over the shroud to supply air to the power ring configuration and to the ram jet engines. 
     The advantages of the design of the present invention are many. The present invention produces a lightweight, low-cost flying vehicle, with very few moving parts and very low maintenance. The machine will run on almost all fuels, and is very stable in gyro hover. The apparatus provides safe and agile navigation, with multi-engine reliability. The machine can fly on one engine much more safely than conventional aircraft and helicopters. The design makes use of one fixed-pitch lifting rotor. Engines and the power ring are buried in a soundproofing shroud, to eliminate the noise problems suffered by Prior Art ram-jet helicopters. 
     In addition to the above advantages, the apparatus of the present invention also has no wings, no horizontal stabilizer, no elevators, no vertical stabilizer, no ailerons, and unlike the “jet jeep”, no tail rotor. The apparatus is safer in an emergency, as the device may auto-rotate to the ground or an optional ballistic parachute may be deployed to further slow descent. In addition, the machine requires no landing gear, further saving weight. 
     The primary features of the present invention include: (1) The Power Ring Configuration Running In The Shroud; (2) The Power Ring Configuration; (3) The Torque Lifting Rotors; (4) The Power Ring Configuration and Torque Lifting Rotor Running Over The Shroud To Hold Air Pushed Down From The Torque Configuration Lifting Rotor; and (5) The Sound-Proof Shroud. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a cutaway perspective view of the preferred embodiment of the present invention. 
         FIG. 2  is top view of power ring  230 . 
         FIG. 3  is a top view of the torque lifting rotor. 
         FIG. 4  is a cross-section view of the preferred embodiment of the present invention. 
         FIG. 5  is perspective view of the preferred embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1  is a cutaway perspective view of the preferred embodiment of the present invention.  FIG. 2  is top view of power ring  230 .  FIG. 3  is a top view of the torque lifting rotor.  FIG. 4  is a cross-section view of the preferred embodiment of the present invention.  FIG. 5  is perspective view of a preferred embodiment of the present invention. 
     Referring to  FIGS. 1-5 , apparatus  100  includes power ring  230 , which may comprise a number of struts  130  (e.g., six) and a circular ring  230 , turning within sound proofing shroud  110 . Attached to power ring  230  are one or more ramjets  180 , which may comprise a jet engine, rocket engine, pulse-jet engine, ramjet or the like. Ramjet(s)  180  turn power ring  230  within sound proofing shroud  110  to produce rotary shaft motion at concentric shaft  125 A of concentric shafts  125 . Sound proofing shroud  110  contains the noise created by ramjets  180  to reduce noise and eliminate the banshee effect produced by Prior Art ramjet helicopters. 
     This rotary motion may in turn be converted, via concentric shafts  125  though control unit and transmission  120 , into rotary motion driving rotor  150  via shaft  125 B of concentric shafts  125 , which may comprise a fixed or variable pitched rotor, or the like. In the preferred embodiment, a single fix pitched rotor is employed with four blades. Torque effects produced by the driving rotor  150  is counteracted, at least in part, by the torque produced by power ring  230 . 
     Sound proofing shroud  110  may be supported by one or more struts  140 , which may attach to frame  170  which may be configured to carry one or more passengers, or in a Remotely Operated Vehicle (ROV) embodiment, may support control and communications equipment. Control unit and transmission  120 A may contain a small starting engine used to drive power ring  230  so as to provide initial rotation to start ramjets  180 . Many types of ramjets require initial air flow in order to ignite, and control unit and transmission  120 A may provide such initial control. Control unit and transmission  120 A may also contain a fuel supply, instrumentation and electronics, and a control yoke, as shown. Note that other types of controls may be used, including a joystick, levers, pedals, and the like. 
     As noted above, in the preferred embodiment, rotor  150  comprises a fixed pitch rotor in order to simplify the design. Vertical lift may be controlled by controlling the rpm of rotor  150 , simply by throttling fuel supply to ramjets  180 . With increased fuel supply, rotor speed increases creating lift. With decreased fuel supply, rotor speed decreases, reducing lift. A governor or the like (not shown) may be used to limit rotor speed to prevent overspeeding of rotor  150 . In an alternative embodiment, a variable pitch rotor may be used, within the spirit and scope of the present invention. In such an embodiment, pitch may be changed to increase or decrease lift. 
     As previously noted, in the preferred embodiment, directional control may be achieved by tilting the rotor in a particular direction using a tilting action at the hub of rotor  150 . However, other control mechanisms may be used within the spirit and scope of the present invention. For example, a traditional cyclic control may be used to alter the pitch of individual rotor blades at different portions of the rotor cycle, in order to alter thrust in a particular direction. 
     The apparatus  100  of the present invention provides many advantages over that of Prior Art helicopters and the like. Should a pilot run out of fuel or experience engine failure (e.g., flameout), the apparatus may auto-rotate toward the ground, reducing the speed of impact. An optional ballistic parachute  190  or the like (e.g., non-ballistic parachute) may be employed as well, extending from the rotor hub  195  or other location. Since the apparatus already is slowed by auto-rotation, a smaller parachute may be employed than traditionally used in ballistic parachute applications. Or, in an alternative embodiment, a larger size parachute may be employed, to provide a slow rate of descent even in the event of a rotor or hub failure (i.e., where lack of autorotation occurs). 
       FIG. 2  is a top view of power ring  230 . Power ring  230  may include a number of struts  130  attaching ring  230  to a central hub. A number of ram jets (e.g., two)  180  may be attached to power ring  230 . When ramjets  180  are activated, power ring  230  rotates, creating rotary shaft motion at the hub. 
     Rotor  150 , may comprise a fixed or variable pitched rotor, or the like. In the preferred embodiment, a single fix pitched rotor is employed with four lifting blades. Torque effects produced by the power ring is counteracted, at least in part, by the use of lifting rotor  150 . 
     Sound proofing shroud  110  may be supported by one or more struts  140 , which may attach to frame  170  which may be configured to carry one or more passengers, or in a Remotely Operated Vehicle (ROV) embodiment, may support control and communications equipment. In additions, struts  135  ( FIG. 4 ) may be provided to secure a top portion of shroud  110  to hub  137  or other location. Any number of struts  135 ,  140  may be used. In the embodiment illustrated, four of each struts  135 ,  140  are employed, although other numbers of struts may be provided to reduce vibration and provide structural integrity to the design. Struts  135  and hub  137  are not shown in  FIGS. 1 and 5  for the sake of clarity. Starting engine and control unit  120 B may contain a small starting engine used to drive the power ring so as to provide initial rotation to start ramjets  180 . Many types of ramjets require initial air flow in order to ignite, and starting engine and control unit  120  B provides such initial controlStarting engine and control unit  120 B may also contain a fuel supply, instrumentation and electronics, and a control yoke, as shown. Note that other types of controls may be used, including a joystick, levers, pedals, and the like. 
     In the preferred embodiment, rotors  150  comprise a fixed pitch rotor in order to simplify the design. Vertical lift may be controlled by controlling the rpm of lifting rotor  150  simply by throttling fuel supply to ramjets  180 . With increased fuel supply to the power ring, rotor speed increases creating lift. With decreased fuel supply, rotor speed decreases, reducing lift. A governor or the like (not shown) may be used to limit rotor speed to prevent overspeeding of rotor  150 . In an alternative embodiment, variable pitch lifting rotors may be used, within the spirit and scope of the present invention. In such an embodiment, pitch may be changed to increase or decrease lift. 
     As previously noted, in the preferred embodiment, directional control may be achieved by tilting the rotor in a particular direction using a tilting action at the hub of rotor  150 . However, other control mechanisms may be used within the spirit and scope of the present invention. For example, a traditional cyclic control may be used to alter the pitch of individual rotor blades at different portions of the rotor cycle, in order to alter thrust in a particular direction. In addition, weight shifting by the operator may be used to alter direction of the apparatus. 
     While the preferred embodiment and various alternative embodiments of the invention have been disclosed and described in detail herein, it may be apparent to those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope thereof.