Patent Publication Number: US-2007114324-A1

Title: Vertical take-off aircraft - F

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
      This is a continuation-in-part patent application, being a continuation-in-part of the U.S. patent application Ser. No. 09/180,925. 
    
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT  
      Not applicable.  
     REFERENCE TO SEQUENCE LISTING  
      Not applicable.  
     BACKGROUND OF THE INVENTION  
     Field of the Invention  
      This invention relates to the vertical take-off field of aviation.  
     BRIEF SUMMARY OF THE INVENTION  
      There are many helicopters in existence today. However, helicopters rely on variable pitch rotor blades to maintain control and provide vertical lift, and the construction of helicopters with variable pitch rotors has resulted in limited operational ability when helicopters are used in forest areas, at high altitudes where the air is thin and when operating near steep mountains. Pitch varying mechanisms require frequent time consuming and expensive maintenance and a failure in the pitch varying mechanism on a helicopter often results in disaster due to instantaneous loss of control that cannot be overcome.  
      The present invention overcomes the need for varying the pitch of rotor blades while at the same time allowing vertical lift on take-off and directional control by providing a vertical take-off aircraft using a propeller or main rotor assembly at the top of the aircraft, which main rotor assembly consists of an assembly of blades and a rotor.  
      Vertical lift is obtained by the rotation of the propeller or main rotor assembly thereby forcing air in a downward direction by way of the angle of pitch of the blades. Rotation of the propeller or main rotor assembly is achieved using a power plant located between the main body of the aircraft and the blades of the propeller or main rotor assembly, which power plant is the main power plant forming part of the aircraft, and which main power plant is connected to the main body of the aircraft by a tilt enabling joint. The tilt enabling joint consists of numerous components, some of which provide the means to support the main body of the aircraft below the main power plant and allow the tilt enabling joint to have a tilting ability while other components provide the means to control and cause tilting motions in the tilt enabling joint during flight, thereby enabling controlled tilting to occur, such that the main power plant and the main rotor assembly can be tilted together as a unity relative to the main body of the aircraft in a controlled manner during flight, thereby providing a means for controlling the directional travel of the aircraft during flight and changing the aircraft&#39;s direction of travel. The propeller or the main rotor assembly and the main power plant can be merged in the form of turboprop. That is, the aircraft could comprise a turboprop at the top of the aircraft, which is connected to the main body of the aircraft by a tilt enabling joint, with vertical lift being achieved by means of the blades of the turboprop forcing air in a downward direction.  
      During flight, rotational stability of the main body of the aircraft is maintained by means of an additional power plant attached to the aircraft which rotates an additional propeller or rotor assembly, thereby pushing air primarily in a horizontal direction to counter the rotational force exerted on the main body of the aircraft by the rotation of the upper main rotor assembly, which said additional rotor assembly consists of an assembly of blades and a rotor. The additional propeller or rotor assembly and the additional power plant can be merged in the form a turboprop or even a jet engine.  
      Hence, in one form the aircraft could comprise a turboprop at the top of the aircraft to force air in a downward direction, which turboprop is connected to the main body by a tilt enabling joint, and an additional turboprop to force air to travel in a horizontal direction to counter the rotational force exerted on main body of the aircraft by operation of the main turboprop at the top of the aircraft.  
      In another form of the aircraft, the aircraft could comprise a turboprop at the top of the aircraft, connected to the main body of the aircraft by a tilt enabling joint, and and a jet that can force exhaust gas to travel in a horizontal direction to counter the rotational force exerted on the main body of the aircraft by operation of the turboprop at the top of the aircraft.  
      As can be seen from the diagrams that follow, the present invention makes many of the components needed to construct a conventional helicopter obsolete, while providing an aircraft that can perform not only tasks normally performed by conventional helicopters but also other tasks that conventional helicopters cannot perform due to their configuration necessitated by variable pitch rotors—such as landing among trees in a forest without cleared landing zones, and grasping trees growing in a forest with grasping mechanisms to gain support and stability by grasping trees.  
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS  
      Embodiments of the invention will now be described by way of example with reference to the accompanying drawings, of which:  
       FIG. 1  is a view of the left side of one form of aircraft according to this invention.  
       FIG. 2A  is a view of the left side of another form of aircraft according to this invention.  
       FIG. 2B  is a view of the right side of the aircraft of  FIG. 2A .  
       FIG. 3  is a view of the rear of yet another form of aircraft according to this invention.  
       FIG. 4  is the left side view of the aircraft of  FIG. 3 .  
       FIG. 5A  is an enlarged view of a universal joint.  
       FIG. 5B  is a rotated view of the universal joint of  FIG. 5A .  
       FIG. 6  shows the main power plant comprising two engines.  
       FIG. 7  shows the additional power plant comprising two engines.  
       FIG. 8  shows one form of the aircraft with the additional power plant and additional rotor assembly replaced by a jet engine.  
       FIG. 9  shows one form of the aircraft with the additional power plant and additional rotor assembly connected to the upper section of a tilt enabling joint.  
       FIG. 10  shows how variable pitch fins could be positioned on the aircraft.  
       FIG. 11  shows how one form of the aircraft could be used to evacuate people from the side of a building.  
       FIG. 12  shows how the main body of the aircraft of  FIG. 9  could make contact with the side of steep mountain while the rotors are kept at a safe distance.  
       FIG. 13  shows that by keeping the main rotor at a large distance from the main body of the aircraft, the aircraft would be able to land among trees while the main rotor is kept above the trees, and grasp surrounding trees with grasping mechanisms.  
       FIG. 14  shows a enlarged view of a grasping mechanism used by the aircraft of  FIG. 13 .  
       FIG. 15  shows that as many as eight rotor blades can be assembled around a small rotor hub when blade pitch varying components are not required.  
    
    
     DETAILED DESCRIPTION OF THE DRAWINGS  
       FIG. 1  shows one form of aircraft according to this invention.  
      Looking at the aircraft in  FIG. 1  it can be seen that the aircraft comprises a main rotor assembly  1  at the top of the aircraft, which rotor assembly consists of an assembly of blades  2 ,  3  and a rotor  4 . Rotation of the main rotor assembly is achieved by using a power plant  5 , which is the main power plant on the aircraft. Vertical lift is obtained by the rotation of the main rotor assembly  1 . Rotation of the main rotor assembly  1  forces air in a downward direction by way of the angle of pitch of the blades  2  and  3 . The blades  2  and  3  are above the main power plant. The main power plant is connected to the main body  6  of the aircraft by a tilt enabling joint  7 . The tilt enabling joint  7  allows tilting of the main power plant  5  relative to the main body  6  of the aircraft to occur in a controlled manner. A universal joint  8  is used to allow tilting to occur. The tilt enabling joint  7  is fitted with a combination of hydraulic actuators  9 ,  10  and springs  11 ,  12  and  13  that allow the tilting of the tilt enabling joint  7  to be controlled. As hydraulic pressure is applied to the front hydraulic actuator  10 , it expands and in so doing tilts the upper section  14  of the tilt enabling joint  7  rearward, thereby compressing the rear spring  13 . As hydraulic pressure to the front hydraulic actuator  10  is released, the rear spring  13  acts to tilt the upper section  14  of the tilt enabling joint  7  forward. When the main power plant  5  is tilted, the main rotor assembly  1  is tilted with it. Tilting of the main power plant  5  thus initiates changes in the direction of travel of the aircraft without the need to change the pitch angles of the blades  2  and  3 . To counter the rotational force exerted on the main body  6  of the aircraft by the rotation of the main rotor assembly  1 ,  FIG. 1  shows an additional power plant  15  attached to the main body of the aircraft, which rotates an additional rotor assembly  16 . The additional rotor assembly consists of blades  17  and  18 , and a rotor  19 . Rotation of the additional rotor assembly pushes air in a primarily horizontal direction by way of the pitch of the blades  17  and  18 . By forcing air to travel in a horizontal direction, the additional rotor assembly acts to counter the rotational force exerted on the main body  6  of the aircraft by the rotation of the main rotor assembly  1 . A grasping mechanism  5   a  is shown positioned on the side of the main body of the aircraft.  
      The Springs  11 ,  12  and  13  shown in  FIG. 1  can be replaced with gas pressurised struts, with the struts fitted in the locations where the springs are located in  FIG. 1 .  FIG. 2A  shows a tilt enabling joint  1  consisting of hydraulic actuators  9 ,  10  and  10   a  being used to control the direction and angle of tilt, and a universal joint  8 . As hydraulic pressure is applied extend to one hydraulic actuator  10  to extend it, hydraulic pressure on the hydraulic actuator  10   a  located directly on the opposite side of the universal joint  8  is released, allowing that hydraulic actuator  10   a  to contract, thereby causing controlled tilting of the upper section of the tilt enabling joint. The movement can be reversed by applying hydraulic pressure to hydraulic actuator  10   a  and releasing hydraulic pressure on hydraulic actuator  10 . With the main power plant  5  attached to the upper section  14  of the tilt enabling joint, when the upper section  14  of the tilt enabling joint is tilted so too is the main power plant  5  and with it the main rotor assembly  1 .  FIG. 2B  shows the aircraft of  FIG. 2A  rotated horizontally 180 degrees to show the hydraulic actuator  10   b  on right side of the tilt enabling joint.  
       FIG. 3  shows the rear view of another form of the aircraft with handles  20  and  21  forming part of the tilt enabling joint  7 . The handles  20  and  21  are attached to the upper section  14  of the tilt enabling joint. The tilting ability of the tilt enabling joint is achieved by the universal joint  8 . The aircraft has a main rotor assembly  1  which is rotated by a main power plant  5 . An additional power plant  15  is used to rotate the additional rotor assembly  16 . Directional control of the aircraft during flight is achieved by controlled tilting of the upper section  14  of the tilt enabling joint relative to the lower section  22  of the tilt enabling joint, thereby tilting the main power plant  5  and main rotor assembly  1 . Controlled tilting of the upper section  14  of the tilt enabling joint during flight is enabled by the handles  20  and  21 . Moving the handles  20  and  21  relative to the main body of the aircraft  6  would be capable of causing a forward and rearward tilting to the upper section of the tilt enabling joint, as well as sideway tilting.  
       FIG. 4  is the left side view of  FIG. 3 , showing the position of the left handle  20  from a side view.  
       FIGS. 5A and 5B  shows the universal joint  8  of the tilt enabling joint of  FIG. 1 .  FIG. 5B  is  FIG. 5A  rotated 90 degrees horizontally.  
       FIG. 6  shows a version of the aircraft with the main power plant  5  comprising two engines  23  and  24 . The main power plant in  FIG. 1  comprised a single engine.  
       FIG. 7  shows the rear of a version of the aircraft of  FIG. 3  with additional power plant  15  comprising two engines  25  and  26 . The additional power plant of the aircraft in  FIG. 3  comprised a single engine.  
       FIG. 8  shows a version of the aircraft of  FIG. 1  with a jet engine  27  replacing the additional power plant  15  shown in  FIG. 1  and the additional rotor assembly  16  also shown in  FIG. 1 . The jet engine is shown connected to the main body of the aircraft. In another form of the aircraft the jet engine is connected to the upper section of the tilt enabling joint. It could also be connected to the main power plant. The jet engine shown is a turbojet. In another form of the aircraft, the jet engine is a turbofan.  
       FIG. 9  shows a version of the aircraft where the additional power plant  15  is attached to the upper section  14  of the tilt enabling joint  7 , with the additional rotor assembly  16  attached to the additional power plant  15 . This feature would allow both the main rotor assembly  1  and the additional rotor assembly  16  to stay high above the ground when the aircraft has landed in a forest. In another form of the aircraft, the additional power plant could be connected to the main power plant.  
       FIG. 10  shows the front of an aircraft similar to the one shown in of  FIG. 9  and how variable pitch fins  28  and  29  could be positioned on the aircraft. The variable pitch fins could augment control of the aircraft, and could be used as airbrakes. They could also provide lift during high speed forward flight, such as wings on an airplane, since downwash from the main rotor assembly  2  would be directed to the rear of the aircraft, due to the tilting of the main rotor assembly in a forward direction and the distance of the main rotor assembly from the variable pitch fins.  
       FIG. 11  shows how an aircraft according to this invention could be used as an evacuation vehicle for persons trapped in a building  30 . An extension ladder  31  secured to the main body  6  of the aircraft is shown in extended form, with a basket  32  at the end of the extension ladder.  FIG. 11  shows how a person  33  could be rescued from the building. The large distance between the main rotor and the main body of the aircraft makes the main body  6  of the aircraft act like a keel on a yacht, so that an extension ladder has a minimal effect on the ability to control the aircraft. The main body could be tilted slightly, while the main rotor assembly  1  could be maintained in a level position.  
       FIG. 12  shows how the aircraft of  FIG. 9  could be used to quickly unload supplies on the side of a steep mountain  34 , or quickly evacuate injured persons without having to use a winch. The relatively short distance between the main rotor and the main body of a conventional helicopter would prevent the main body of a conventional helicopter being able to make contact with such a steep mountain without a high risk of the rotor blades impacting with the mountain.  
       FIG. 13  shows how the aircraft of  FIG. 11  could land between trees  35  and  36 , while the main rotor assembly is kept above the tops of the trees. Cargo could be loaded and unloaded or injured persons evacuated without using a winch. Grasping mechanisms  37  and  38  are shown grasping trees  35  and  36  respectively, providing support and stability for the aircraft while a sharpened section  39  protruding beneath the main body bears some of the weight of the aircraft.  
       FIG. 9  showed the aircraft with the additional power plant  15  and the additional rotor assembly  16  connected to the upper section of the tilt enabling joint. By attaching the additional rotor assembly  16  and the additional power plant  15  to the upper section of the tilt enabling joint, the additional rotor assembly could be kept above trees when the aircraft is landed amongst trees as shown in  FIG. 13 . The aircraft could land in an area such as a forest where the rotors of a conventional helicopter would impact with the trees. The aircraft would not require a cleared landing zone to land in a forest. In a war, the possible landing area would be less predictable by an enemy force, reducing the risk of an ambush around a cleared landing zone. If the aircraft was operated on a battle field and the aircraft was targeted by a heat seaking missile during flight, having the main power plant and the additional power plant located away from the main body of the aircraft would provide the occupants with a greater chance of survival than if the main power plant was attached directly to the main body of the aircraft if the missile caused a fire at the main power plant. The additional power plant  15  and additional rotor assembly could also be attached to the base of the tilt enabling joint, or the main power plant.  
       FIG. 14  shows the grasping mechanism  38  from  FIG. 13  as viewed from above. The grasping mechanism comprises a moveable component  42   a  which can be moved towards a rigid component  42   b  by hydraulic actuator  43   a . Expansion of the hydraulic actuator  43   a  creates a grasping motion between  42   a  and  42   b . The grasping mechanism is connected to the main body of the aircraft by a hollow beam  40   a , which can be extended outward by means of hydraulic actuator  41   a , such that the beam  40   a  can operate in a telescopic manner sliding in and out of an enclosure  40   b . The enclosure  40   b  is connected to the main body of the aircraft by a bolt  41   b , which enables the enclosure  40   b  to swivel relative to the main body. The swiveling motion of the enclosure  40   b  is controlled by hydraulic actuator  43   b . Hydraulic actuator  43   b  is connected to the enclosure  40   b  and the main body of the aircraft.  
       FIG. 15  shows how eight rotor blades  44 ,  45 ,  46 ,  47 ,  48 ,  49 ,  50 ,  51 , can be assembled around a rotor  4  when space is not required for blade pitch varying components. This number of rotor blades would allow the rotor assembly  1  to be rotated at a lower rate of revolution than a rotor assembly with fewer blades, to achieve the same lifting ability, resulting in a relatively quieter aircraft. Having a high number of rotor blades would help the aircraft to operate in high altitude mountainous regions or hot regions, where the air is thin.