JP2007203008A - Vertical taking off and landing airplane - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a radio-controlled model plane of a vertical taking off and landing airplane capable of hovering by eliminating a complicated structure and complicated control and reducing its weight. <P>SOLUTION: This vertical taking off and landing airplane adopts a system that a propeller used usually in the radio-controlled model plane is used as one machine to obtain power and is mounted by facing upward to control front, rear, left, and right sides by the air dividing a part of its thrust when hovering. When shifting from hovering to advance flight, an opening and closing door at a lower part is closed and thrust is deflected onto a rear side to perform usual advance flight. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention particularly relates to a radio-controlled model airplane, but can also be applied to the field of actual aircraft.

Various types have been conceived as vertical take-off and landing of radio controlled model airplanes, and production and experiments have been made, and other ideas have been released.
Radio control technology magazine February 2003 issue p192, 193 Radio Control Technology Magazine March 2003 issue p194, 195 Radio control technology magazine July 2003 issue p32, 34 Radio Control Technology Magazine September 2005 issue p27-29 In addition, as a conventional vertical take-off and landing aircraft, the main wing has two or four propellers, and when propelled vertically, the propeller or the entire wing is rotated and deflected upwards to obtain thrust, and during forward flight, the propeller or wing There are types that fly forward like a normal airplane by rotating and deflecting the whole forward, and types that use propellers for vertical ascent or duct fans and propellers for forward flight separately. Equipped with four duct fans, and when vertically rising, the attitude is controlled by adjusting the duct fan thrust of each of the four while raising the entire duct fan downwards. Some types fly forward. In addition, in the case of mainly hovering flight, in the type of one duct fan, a plurality of wings for controlling the jet direction are provided in the lower part of the duct, thereby controlling the front / rear and left / right postures, and the plurality of ducts There are those equipped with fans, which control the front / rear / left / right posture or roll axis by moving the thrust of each duct fan or the wing for controlling the jet direction.

When the main wing is equipped with two or four propellers that can rotate and deflect, there is no problem as a normal airplane during forward flight. The propeller rotation speed or pitch must be changed to change the thrust, and in order to control the front-rear posture, the propeller thrust direction toward the upper direction must be finely deflected back and forth, or the tail Or it is necessary to equip a front part with a propeller or jet nozzle for attitude control, and it is complicated and difficult to control.

  In the case of a single duct fan type, the posture including the yaw axis is controlled by moving the blade that changes the jet direction provided in the lower part of the duct. However, the center of gravity is at the top and the jet is deflected directly. In order to achieve stability, a high-performance gyro is required, and control is rather delicate and difficult. In the case of four duct fan types, the duct body must be rotated, so the mechanism is difficult, and if it is done with a single engine, the problem of how to move the power shaft Even when the four engines are independent, in order to control each thrust, it is necessary to change the number of revolutions or the pitch of the fan, which makes the structure complicated and difficult to control.

  Therefore, in the present invention, the engine is fixed in the fuselage as a single unit, and a duct is provided in the vertical direction, and a plurality of doors provided at the lower part of the duct are opened and closed, so that a jet flow is taken downward as it is during hovering. In order to obtain a rising thrust and perform a horizontal flight, the lower door is closed and the jet is blown backwards.When hovering, a part of the jet is guided from the inside of the propeller duct to a position somewhat away from front to back and left and right. The pitch, roll and yaw triaxial control was performed by blowing.

  In that case, as described in claim 2, by jetting the jets blown out from the posture control ducts up and down in the normal state, it serves as a “wedge” in the air, and the effect of maintaining the posture is enhanced. . Further, when changing the posture, a strong rotational moment can be generated by changing the strength of the upper and lower balloons and making them opposite to each other on the left and right or front and back. As for the length of the attitude control duct, the longer one controls the rotational moment, but if it is too long, the fluid resistance in the duct increases and the momentum of the jet that blows out weakens. It seems that it is generally within 1 to 2 times the diameter of the propeller duct.

  Further, as described in claim 3, with respect to the method for generating the rotational force for yaw axis control, the jet flow blown from the front / rear / right / left attitude control duct tip remains in the vertical direction, and the longitudinal direction of the duct is viewed from above. This is done by changing the direction of the blowing jet forward or backward in a perpendicular direction. In this case, the structure for changing the direction of the blowout jet is to provide a deflecting device composed of a plurality of guide plates above and below the posture control duct blowout opening and to move it back and forth simultaneously. The deflection angle is set to about 45 degrees at the maximum, whereby a jet flow is obliquely blown forward or backward to obtain a rotational force around the yaw axis. Place it in front and rear, left and right two pairs, or all four pairs.

  These axes cannot be controlled by human operation, and a gyro is added to the control servo for each axis.

  The attitude control duct has four jet inlets in the front, rear, left and right within the propeller duct, but is closed when performing horizontal flight. The reason is that if a flight is carried out with a jet flow from the attitude control duct as it is, the jet flow becomes a large air resistance and falls to a speed at which it cannot fly. As the opening / closing structure, as shown in FIG. Further, if a large number of attitude control jets are taken out, the control force becomes stronger, and the attitude control becomes easier, and the response and stability during maneuvering become stronger. On the other hand, since the force to lift the aircraft decreases, there is a risk that it will not be possible to ascend vertically. Therefore, the size (area) of the intake port for the posture control jet is set to be within about 20 to 30% of the propeller duct area (circular area) for the four locations.

  As shown in FIG. 8, the structure of the open / close door that distributes the jets installed below the propeller ducts downward and rearward is composed of several revolving doors that move together in the vertical or horizontal direction. In that case, since it must open and close against the momentum of the jet flow, in order to reduce the driving force, a structure is adopted in which a rotating shaft is provided at the center in the horizontal direction of the door.

  At the time of level flight, the center point of the jet flowing backward is structurally slightly above the center of gravity of the aircraft in the vertical direction. In order to prevent this, as shown in FIG. 11, a deflection plate is attached so as to raise the bottom half of the rear jet to a certain length and raise the latter half upward slightly to raise the center of the jet above the bottom. Alternatively, as shown in FIG. 12, the jet outlet is extended horizontally and the outlet is tilted slightly downward, so that the thrust center of the jet pushes near the center of gravity of the fuselage, preventing head rise and performing stable flight. I can do it.

  As for the shape of the jet outlet, if the jet outlet width is extended while keeping the same as the duct diameter due to the low height in the vicinity of the structure, the jet outlet area becomes considerably smaller than the duct area, so the discharge resistance is reduced. It becomes larger and the thrust when moving forward decreases considerably. Further, the thrust is further reduced by the jet deflection described above. In order to reduce the thrust drop, as shown in FIG. 13, the width of the lower part of the duct is gradually widened from the front, and the jet area is arranged so that the vicinity of the outlet is parallel to the longitudinal direction of the fuselage. And the thrust can be significantly increased by preventing the jet from spreading sideways. At the same time, the side shape can be further improved by gradually curving from the upper front side of the duct to make the flow in the duct smooth. In that case, the lower opening / closing door may have a structure in which a plurality of doors perpendicular to the body axis are provided.

  In order to improve the suction efficiency, the upper air intake port of the propeller duct has a large radius and projects in an arc shape with the periphery of the entrance facing outward. (Also referred to as funnel) This increases the suction efficiency and increases the thrust during hovering. In order to improve the suction efficiency during horizontal flight, the propeller duct surface may be inclined slightly forward from the horizontal plane.

  The fuel tank of the engine is divided into two places on the left and right or front and rear with respect to the propeller center, and both are decreased at the same time so that the movement of the center of gravity due to increase or decrease of fuel is eliminated.

  When flying a radio controlled airplane with the vertical take-off and landing aircraft according to the present invention, a runway having a length of at least about 100 m and a width of about 10 m or more is necessary. Then, since it is sufficient if there is a vacant lot of about several square meters, you can easily get the pleasure of flying a radio-controlled airplane without struggling to secure an airfield like before. Also, when used as an aerial photography platform by radio control, the structure is simpler than that of a commonly used helicopter, and the manufacturing cost is much cheaper, so the cost of photography can be reduced, and the helicopter In the case of a crash due to lack of control and other factors like this, the safety is high, and an emergency parachute can be equipped so that it can be recovered more safely and crashed as it is. However, since the rotating propeller is inside, damage to other parts can be reduced compared to aircraft such as helicopters. Furthermore, the vertical take-off and landing aircraft according to the present invention can be used as an industrial aerial photography platform in addition to being used as a radio controlled airplane. In addition, it can be applied to actual machines on which humans can ride.

  When flying the vertical take-off and landing aircraft according to the present invention, the hovering mode (with the lower opening / closing opening and the air intake for attitude control being opened, and the gyro When the aircraft is lifted in the operating state) and takes a certain altitude (about 10 times the total length of the aircraft), the flight mode (lower opening / closing port and attitude control air intake port is closed, while the gyro is still moving while moving forward slightly forward Switch forward to inactive state and fly forward. When moving from forward flight to hovering, lower the speed of forward flight while heading to the landing point, switch to hovering mode and land at an appropriate altitude. It is also possible to take off and land while sliding in a forward flight state like a general airplane.

  As an embodiment, the airframe of FIG. 1 can be mentioned, but in order to have the desired performance, it is necessary to make it considerably lighter than a conventional airframe of the same engine size. When the engine size is 40 class, it is about 3 kg to 4 kg for a normal aircraft, but it must be at least about 2.5 kg. For this purpose, carbon FRP or the like is used as the airframe structure material, and the structure of the wing is made of balsa or film tension.

  Mainly used for hobby and industrial use.

Overall view Attitude control during hovering Internal air flow viewed from the side during hovering Air flow when trying to change to a posture where the aircraft rotates backward (pitch up) during hovering Air flow during forward flight Direction of jet flow for yaw axis control viewed from the side of the aircraft Example of the structure of the device that changes the jet discharge direction for yaw axis control Structural diagram of the door that changes the jet direction of the jet below the duct, 2 types Opening / closing mechanism of air intake for posture control in duct, 2 types A state in which a rectifying plate is installed to smoothly flow the jet in the duct backward. In order to prevent pitch-up during flight, with a rectifying plate attached to bring the center of the rear discharge jet closer to the center of gravity Similarly, in order to prevent pitch-up during flight, an example of installing a rectifying plate in the rear to bring the center of the rear discharge jet closer to the center of gravity Jet outlet shape to increase thrust during forward flight (increase rear jet outlet area) Example when the aircraft design is a delta wing Example of application as an aerial photography platform

Explanation of symbols

1 Engine 2 Attitude control jet outlet (up and down)
3 Propeller 4 Propulsion jet outlet 5 Camera equipment 6 Aircraft recognition marker

Claims (3)

  Equipped with an engine with a propeller in the duct that is tilted upward or slightly forward in the center of the fuselage. The pitch, yaw, and roll three axes are controlled by guiding them to the mouth and adjusting the jet direction there. When performing forward flight, close the open / close door at the bottom of the duct and let the jet flow backward. Vertical take-off and landing aircraft characterized by gaining forward thrust.   With regard to pitch and roll axis control during hovering, in a normal state, the jet flow control valve provided inside each blow-out port is made neutral, so that the jet flow from the blow-out port is made equal in the vertical direction, and the posture at that time is kept strong In order to obtain stability and change posture, each jet flow control valve is moved to change the upper and lower blowout amount. , Structure and method to get tilt force.   Regarding the control of the yaw axis during hovering, the jet flow from the left and right or front and rear outlets can be deflected in the direction perpendicular to the outlet when viewed from the top of the aircraft at the same time. A structure and method that obtains the rotational force of the yaw axis by reversing it.

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