WO2022224331A1 - Aéronef - Google Patents

Aéronef Download PDF

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Publication number
WO2022224331A1
WO2022224331A1 PCT/JP2021/015968 JP2021015968W WO2022224331A1 WO 2022224331 A1 WO2022224331 A1 WO 2022224331A1 JP 2021015968 W JP2021015968 W JP 2021015968W WO 2022224331 A1 WO2022224331 A1 WO 2022224331A1
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WO
WIPO (PCT)
Prior art keywords
engine
generator unit
frame
aircraft
connecting portion
Prior art date
Application number
PCT/JP2021/015968
Other languages
English (en)
Japanese (ja)
Inventor
浩一 田中
Original Assignee
ヤマハ発動機株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by ヤマハ発動機株式会社 filed Critical ヤマハ発動機株式会社
Priority to JP2021576080A priority Critical patent/JP7081060B1/ja
Priority to PCT/JP2021/015968 priority patent/WO2022224331A1/fr
Publication of WO2022224331A1 publication Critical patent/WO2022224331A1/fr

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B64—AIRCRAFT; AVIATION; COSMONAUTICS
    • B64U—UNMANNED AERIAL VEHICLES [UAV]; EQUIPMENT THEREFOR
    • B64U50/00—Propulsion; Power supply
    • B64U50/30—Supply or distribution of electrical power
    • B64U50/33—Supply or distribution of electrical power generated by combustion engines
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B64—AIRCRAFT; AVIATION; COSMONAUTICS
    • B64D—EQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENT OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT
    • B64D27/00—Arrangement or mounting of power plants in aircraft; Aircraft characterised by the type or position of power plants
    • B64D27/02—Aircraft characterised by the type or position of power plants
    • B64D27/04—Aircraft characterised by the type or position of power plants of piston type
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B64—AIRCRAFT; AVIATION; COSMONAUTICS
    • B64D—EQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENT OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT
    • B64D27/00—Arrangement or mounting of power plants in aircraft; Aircraft characterised by the type or position of power plants
    • B64D27/02—Aircraft characterised by the type or position of power plants
    • B64D27/10—Aircraft characterised by the type or position of power plants of gas-turbine type 
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B64—AIRCRAFT; AVIATION; COSMONAUTICS
    • B64D—EQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENT OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT
    • B64D27/00—Arrangement or mounting of power plants in aircraft; Aircraft characterised by the type or position of power plants
    • B64D27/02—Aircraft characterised by the type or position of power plants
    • B64D27/24—Aircraft characterised by the type or position of power plants using steam or spring force
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B64—AIRCRAFT; AVIATION; COSMONAUTICS
    • B64D—EQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENT OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT
    • B64D27/00—Arrangement or mounting of power plants in aircraft; Aircraft characterised by the type or position of power plants
    • B64D27/40—Arrangements for mounting power plants in aircraft
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B64—AIRCRAFT; AVIATION; COSMONAUTICS
    • B64U—UNMANNED AERIAL VEHICLES [UAV]; EQUIPMENT THEREFOR
    • B64U10/00—Type of UAV
    • B64U10/10—Rotorcrafts
    • B64U10/13—Flying platforms
    • B64U10/14—Flying platforms with four distinct rotor axes, e.g. quadcopters
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
    • F16F15/00—Suppression of vibrations in systems; Means or arrangements for avoiding or reducing out-of-balance forces, e.g. due to motion
    • F16F15/02—Suppression of vibrations of non-rotating, e.g. reciprocating systems; Suppression of vibrations of rotating systems by use of members not moving with the rotating systems

Definitions

  • the present invention relates to an aircraft.
  • a flying object that has a plurality of rotors that generate lift, including an electric motor and a propeller that is rotationally driven by the electric motor.
  • a flying object for example, as disclosed in Patent Document 1, a flying object including an airframe, a flight motor unit, a power generation unit, and a power generation unit suspension mechanism is known.
  • the power generation unit has a generator that supplies power to the flight motor unit and an engine that drives the generator.
  • the power generation unit suspension mechanism suspends the power generation unit below the airframe.
  • the power generation unit suspending mechanism has a vibration-retaining member, a frame member, and a suspending member, and is constructed using a lightweight carbon fiber material or the like.
  • the power generation unit suspension mechanism absorbs vibrations caused by driving the power generation unit with a damper member provided on the frame member.
  • an aircraft having multiple rotors for example, as disclosed in Patent Document 2, it includes a fuselage, rotors, an engine module, a generator module, a head assembly, and a plurality of damping assemblies.
  • Unmanned aerial vehicles are known.
  • the plurality of damping assemblies are provided between the airframe and the engine module and the generator module.
  • the plurality of damping assemblies including cushion rubber dampers or damping springs, have a damping effect on vibrations generated by the engine module and the generator module.
  • the flying objects disclosed in Patent Documents 1 and 2 above have a configuration capable of absorbing vibrations caused by the driving of the engine and generator.
  • a configuration capable of absorbing vibrations caused by driving the engine-generator unit is desired.
  • a lightweight configuration is desired. That is, the flying object is required to have a lightweight structure capable of absorbing vibrations generated by driving the engine-generator unit.
  • An object of the present invention is to realize a configuration of a lightweight aircraft capable of absorbing vibrations generated by driving an engine generator unit.
  • the inventor studied the configuration of a lightweight aircraft capable of absorbing the vibrations caused by the driving of the engine-generator unit. As a result of intensive studies, the inventors came up with the following configuration.
  • a flying object includes an electric motor and a propeller rotationally driven by the electric motor, a plurality of rotors that generate lift, and electric power supplied to the electric motors of the plurality of rotors.
  • An aircraft comprising: an engine-generator unit that generates a rotor; a frame that supports the plurality of rotors and the engine-generator unit; and a plurality of connecting portions that connect the engine-generator unit and the frame.
  • Each of the plurality of connecting portions is arranged such that the natural frequency of the connecting portion when the engine-generator unit is supported on the frame is lower than the vibration frequency generated by driving the engine-generator unit. includes fabrics in which multiple fibers are woven.
  • the engine generator unit is connected to the frame, and the natural frequency of the connecting portion in a state in which the engine generator unit is supported with respect to the frame is lower than the vibration frequency generated by driving the engine generator unit.
  • the connecting portion including the fabric in which a plurality of fibers are woven can suppress transmission of vibrations generated by driving the engine-generator unit to the frame.
  • the connecting portion includes a fabric in which a plurality of fibers are woven, compared with the case where the connecting portion is made of metal or the like, the structure of the connecting portion can be obtained with a higher degree of freedom in design, and the aircraft can be made lighter.
  • the flying object of the present invention preferably includes the following configurations.
  • the fabric is woven such that the plurality of fibers are relatively displaceable so that at least part of the vibration of the engine-generator unit is damped.
  • connection including the woven fabric in which a plurality of fibers are relatively displaceable so that at least part of the vibration of the engine-generator unit is damped at least part of the vibration generated by the driving of the engine-generator unit.
  • the connection including the woven fabric in which a plurality of fibers are relatively displaceable so that at least part of the vibration of the engine-generator unit is damped at least part of the vibration generated by the driving of the engine-generator unit.
  • the connection including the woven fabric in which a plurality of fibers are relatively displaceable so that at least part of the vibration of the engine-generator unit is damped at least part of the vibration generated by the driving of the engine-generator unit.
  • the flying object of the present invention preferably includes the following configurations.
  • the flying object has at least three connecting portions.
  • the engine-generator unit is connected to the frame via at least three of the connecting portions.
  • the engine-generator unit can be connected to the frame in a more stable posture by means of at least three connecting portions each including a fabric.
  • the at least three joints can more effectively absorb vibrations caused by the driving of the engine-generator unit, and the weight of the flying object can be reduced compared to the case where the joints are made of metal or the like. can be done.
  • the flying object of the present invention preferably includes the following configurations. At least some of the plurality of connecting portions include a woven fabric having fibers extending in different directions in a plan view of the aircraft.
  • the engine-generator unit is connected to the frame via the at least one connecting portion that includes a woven fabric having fibers extending in different directions in a plan view of the aircraft.
  • the engine-generator unit can be connected to the frame with higher strength via the connecting portion including the fabric with fibers extending in different directions in plan view of the aircraft.
  • the connecting portion including the fabric with fibers extending in different directions in a plan view of the flying object can more absorb the vibration caused by the driving of the engine generator unit, and compared to the case where the connecting portion is made of metal or the like, It is possible to reduce the weight of the aircraft.
  • the flying object of the present invention preferably includes the following configurations.
  • the woven fabric included in each of the plurality of connecting portions includes a woven fabric woven with fibers whose base material is mainly composed of an organic substance.
  • the engine-generator unit can be more reliably connected to the frame by the connecting portion including the fabric.
  • the connecting portion including the fabric woven with fibers whose base material is mainly composed of an organic substance can absorb the vibration caused by the driving of the engine-generator unit, and when the connecting portion is made of metal or the like, In comparison, the aircraft can be made lighter.
  • the flying object of the present invention preferably includes the following configurations.
  • the engine-generator unit includes an engine-generator unit connecting portion, which is a connection portion between the engine-generator unit and the connecting portion, and a connecting portion between the connecting portion and the frame during flight of the aircraft. It is connected to the frame by the connection portion such that the shortest distance to the frame connection portion is longer than the horizontal distance between the engine generator unit connection portion and the frame connection portion.
  • the spring constant of the connection portion including the fabric in which a plurality of fibers are woven is determined by the shortest distance between the engine generator unit connection portion and the frame connection portion. can be smaller than the spring constant equal to the horizontal distance between Therefore, the natural frequency of the connecting portion can be made lower than the frequency of vibration caused by driving the engine-generator unit. Therefore, the connecting portion can effectively absorb vibrations caused by driving the engine-generator unit.
  • the aircraft can be made lighter than when the connecting portion is made of metal or the like. can be done.
  • the flying object of the present invention preferably includes the following configurations.
  • the engine-generator unit connection portion which is the connection portion between the engine-generator unit and the connection portion, is the connection portion between the connection portion and the frame during flight of the aircraft. It is connected to the frame by the connecting portion so as to be located below the frame connecting portion.
  • the engine-generator unit can be supported by the frame during the flight of the aircraft by means of the connecting portion including the fabric woven with a plurality of fibers.
  • the connecting portion including the fabric can absorb the vibration caused by the driving of the engine-generator unit, and the weight of the aircraft can be reduced compared to the case where the connecting portion is made of metal or the like.
  • attachment As used herein, “attached,” “connected,” “coupled,” and/or equivalents thereof are used broadly and include “direct and indirect” attachment, It includes both connection and coupling. Furthermore, “connected” and “coupled” are not limited to physical or mechanical connections or couplings, but can include direct or indirect electrical connections or couplings.
  • the flying object is a moving object that can move in the air by a driving force obtained by a driving source such as a motor.
  • the aircraft means, for example, a multicopter having a plurality of rotors.
  • the rotating shafts of the plurality of rotors extend vertically.
  • the plurality of rotors are driven by an electric motor.
  • the aircraft is equipped with at least a generator, and is configured to be able to supply electric power generated by the generator to the electric motor.
  • the air vehicles include both unmanned air vehicles and manned air vehicles.
  • an engine-generator unit is a device that generates power by driving a generator with various reciprocating engines such as a diesel engine and a gasoline engine.
  • the engine generator unit generates power by controlling the output of the engine in response to an electric power generation request from the outside.
  • a fiber is an elongated material from which textiles are woven.
  • the fibers are twisted in the longitudinal direction to form threads. That is, the fiber is the raw material of the thread.
  • Said fibers include both natural and synthetic fibers.
  • a woven fabric is a fabric obtained by weaving fibers or threads of twisted fibers.
  • a state in which the engine generator unit is supported by the connecting portion means a state in which the engine generator unit is supported by the frame via the connecting portion.
  • the state in which the connecting portion supports the engine-generator unit is a state in which at least part of the weight of the engine-generator unit acts on the connecting portion to generate a tensile force.
  • the base material is mainly composed of organic substances
  • the expression that the base material is mainly composed of an organic substance means that a component accounting for half or more of the components contained in the fiber is composed of an organic substance.
  • FIG. 1 is a plan view showing a schematic configuration of an aircraft according to Embodiment 1.
  • FIG. FIG. 2 is a side view showing a schematic configuration of the aircraft according to Embodiment 1.
  • FIG. FIG. 3 is a plan view showing a schematic configuration of an aircraft according to Embodiment 2.
  • FIG. 4 is a side view showing a schematic configuration of an aircraft according to Embodiment 2.
  • FIG. 5 is a side view showing a schematic configuration of an aircraft according to another embodiment.
  • FIG. 6 is a side view showing a schematic configuration of an aircraft according to another embodiment.
  • FIG. 7 is a plan view showing a schematic configuration of an aircraft according to another embodiment.
  • FIG. 1 is a plan view showing a schematic configuration of an aircraft 1.
  • FIG. 2 is a side view showing a schematic configuration of the aircraft 1.
  • FIG. 1 is a plan view showing a schematic configuration of an aircraft 1.
  • the flying object 1 according to Embodiment 1 of the present invention is a multicopter that flies with a plurality of rotors 5.
  • the flying object 1 is configured to be capable of wireless remote control and autonomous flight using various sensors.
  • the aircraft 1 includes a body frame 2 , an engine generator unit 3 , a plurality of connecting sections 4 , a plurality of rotors 5 and an aircraft control device 6 .
  • the fuselage frame 2 supports an engine generator unit 3, a battery (not shown), a rotor 5, and an aircraft controller 6.
  • the body frame 2 has a frame body portion 21 and a plurality of rotor support portions 26 .
  • the body frame 2 is made of, for example, an aluminum alloy pipe material.
  • a body frame 2 corresponds to the frame.
  • the frame main body 21 supports the engine generator unit 3.
  • the frame main body portion 21 has, for example, a loop shape in a plan view of the aircraft 1 .
  • the frame main body 21 may have any shape, such as a rectangular shape, an annular shape, or a polygonal shape, when viewed from above the aircraft 1 .
  • At least part of the frame main body 21 is configured by a rod-shaped or pipe-shaped member.
  • the frame body portion 21 may have a shape other than the loop shape, such as a beam shape, as long as it is a shape capable of supporting the engine generator unit 3 .
  • At least part of the frame main body 21 may be configured by a plate-like member.
  • the rotor support portion 26 supports the rotor 5.
  • the rotor support portion 26 is connected to the frame body portion 21 .
  • the plurality of rotor support portions 26 radially extend with respect to the frame body portion 21 in a plan view of the aircraft 1 .
  • the plurality of rotor support portions 26 are preferably arranged point-symmetrically with respect to the center of the frame main body portion 21 in a plan view of the aircraft 1 .
  • the engine generator unit 3 is a device dedicated to power generation that drives the generator 31 with the driving force of the power generation engine 32 to generate power.
  • the engine generator unit 3 has a generator 31 and a generator engine 32 .
  • the power generator 31 is rotated by the power supplied from the power generation engine 32 to generate power.
  • the generator 31 is, for example, an AC generator.
  • the generator 31 converts the generated AC power into DC power and outputs it to a battery (not shown). Note that the generator 31 may supply the converted DC power to the electric motor 51 of the rotor 5, which will be described later.
  • the generator 31 has a rotor (not shown).
  • the rotor of the generator 31 is connected to the power generation engine 32 so as to be driven by the power output from the power generation engine 32 .
  • the power generation engine 32 is a power source that drives the generator 31 .
  • the power generation engine 32 has a piston (not shown) connected to a crankshaft (not shown) via a connecting rod (not shown).
  • the power generation engine 32 reciprocates the piston to rotate the crankshaft.
  • the power generation engine 32 is, for example, a two-cylinder horizontally opposed engine.
  • the generator engine may be an engine other than a two-cylinder horizontally opposed engine.
  • the rotors of the generator 31 are connected to both ends of the crankshaft of the power generation engine 32, respectively. That is, the two power generators 31 are drivably connected to the power generation engine 32 .
  • the power generation engine 32 drives the two power generators 31 by rotational motion of the crankshaft.
  • the generator 31 and the generator engine 32 are controlled by a generator control device and an engine control device (not shown) based on an external power command, power generation amount, remaining battery capacity, and the like.
  • the number of generators driven by the power generation engine may be one or three or more.
  • the engine generator unit 3 is supported by the frame main body 21 via a plurality of connecting portions 4. As shown in FIG. The plurality of connecting portions 4 are connected to the engine generator unit 3 and also connected to the frame body portion 21 . That is, each connecting portion 4 has one end connected to the engine generator unit 3 and the other end connected to the engine generator unit 3 . In this embodiment, the engine generator unit 3 is connected to the frame main body 21 by four connecting portions 4 .
  • Two of the four connecting portions are connected to a portion of the engine-generator unit 3 located on one side of the crankshaft (not shown) in the axial direction of the power-generating engine 32.
  • the connecting portion is connected to a portion located on the other side in the axial direction of the power generation engine 32 .
  • the four connecting portions are connected to the engine-generator unit 3 at symmetrical positions with respect to the center of gravity of the engine-generator unit 3 in the plane view of the aircraft 1 in the axial direction and in the direction orthogonal to the axial direction. preferably A detailed configuration of the connecting portion 4 will be described later.
  • Each connecting portion 4 and the engine generator unit 3 may be directly connected, or may be connected via a connecting member such as a metal fitting. Each connecting portion 4 may have a connection fitting connected to the engine generator unit 3 . Each connecting portion 4 and the frame main body portion 21 may be directly connected, or may be connected via a connecting member such as a metal fitting. Each connecting portion 4 may have a connection fitting connected to the frame body portion 21 .
  • connection positions of the plurality of connecting portions 4 with respect to the engine generator unit 3 are not limited to the above-described positions, and any position where the engine generator unit 3 can be supported on the frame main body portion 21 by the plurality of connecting portions 4 can be used. position.
  • the flying object control device 6 controls the position, attitude, speed, flight direction, etc. of the flying object 1 by controlling the driving of the plurality of rotors 5 based on externally input control signals and the like.
  • the aircraft control device 6 may have a configuration in which, for example, a CPU, ROM, RAM, HDD, etc. are connected by a bus. Further, the flying object control device 6 may be configured by a one-chip LSI or the like.
  • Various programs and programs for controlling the rotation speed of each rotor 5, controlling the operation of the power generating engine 32, the generator 31, the battery (not shown), the measuring device (not shown), etc. data is stored.
  • the flying object control device 6 has an inertial measurement device, a direction sensor, an altitude sensor, and the like.
  • the inertial measurement device is a device that measures the triaxial angular velocity and angular acceleration of the flying object 1 . Since the inertial measurement device accurately measures the angular velocity and angular acceleration of the flying object 1 during flight, it is necessary to suppress the vibration velocity and vibration acceleration applied to the inertial measurement device below threshold values.
  • the aircraft control device 6 is configured to be able to transmit a generator control signal to the engine control device and the generator control device described above.
  • the aircraft control device 6 is configured to be able to transmit a drive control signal to the power conversion device 53 of the rotor 5 .
  • the flying object control device 6 obtains measured values of the angular velocity and angular acceleration of the flying object 1 from the inertial measurement device, obtains measured values of the heading of the flying object 1 from the orientation sensor, and obtains measured values of the heading of the flying object 1 from the altitude sensor. altitude measurements can be obtained.
  • the flying object control device 6 can generate the power generation control signal and the drive control signal from the acquired measurement values.
  • the aircraft control device does not have to have an inertial measurement device.
  • the aircraft control device does not have to have an orientation sensor.
  • the aircraft control device may not have an altitude sensor.
  • the flying body control device 6 is supported by the flying body control device support section 7 .
  • the aircraft control device support portion 7 is fixed to the frame body portion 21 .
  • the aircraft control device support section 7 has a plurality of support legs 71 and a mounting plate 72 .
  • a plurality of support legs 71 are connected to the frame main body 21 and support the mounting plate 72 .
  • the aircraft control device support section 7 has two support legs 71 .
  • the aircraft control device support section may have one support leg, or may have three or more support legs.
  • the mounting plate 72 is a rectangular plate-like member supported by a plurality of support legs 71 .
  • the aircraft control device 6 is fixed on the mounting plate 72 .
  • the mounting plate 72 is positioned at the center of the frame main body 21 in plan view of the aircraft 1 .
  • the connecting portion 4 is a woven fabric formed by weaving fibers whose base material is mainly composed of an organic substance. A plurality of the fibers are woven in the fabric so that the fibers are relatively displaceable so that at least part of the vibration generated by driving the engine-generator unit 3 is damped.
  • the woven fabric is, for example, a strip-shaped belt.
  • the woven fabric is, for example, a woven fabric obtained by plain weaving in which threads obtained by twisting fibers are woven one by one in the vertical and horizontal directions. A woven fabric obtained by such a plain weave has high tensile strength and is resistant to friction.
  • the woven fabric may be a woven fabric obtained by twill weaving.
  • Twill weave is a weave in which warp yarns pass over two or three weft yarns and then under one weft yarn repeatedly.
  • a woven fabric obtained by such a twill weave has excellent stretchability and is less prone to wrinkles.
  • the fibers are, for example, natural fibers, synthetic fibers, and the like.
  • the fibers include, for example, fibers composed of polyester, nylon, aramid, vinylon, polyvinyl chloride, acrylic, polyethylene, polypropylene, polyurethane, polyclar, polylactic acid, and the like.
  • the Young's modulus of polyester is, for example, 2100 to 4200 MPa
  • the Young's modulus of nylon is, for example, 1000 to 2600 MPa.
  • the base material is mainly organic matter
  • the base material means that more than half of the components contained in the fiber are organic matter.
  • the connecting portion 4 has an engine generator unit connecting portion 41 and a frame connecting portion 42 .
  • the engine generator unit connecting portion 41 is a portion of the connecting portion 4 that is connected to the engine generator unit 3 .
  • the frame connecting portion 42 is a portion of the connecting portion 4 that is connected to the frame body portion 21 of the body frame 2 .
  • the engine generator unit 3 is a device that generates electric power, so it does not receive a driving reaction force unlike an engine that outputs driving force. Therefore, the engine-generator unit 3 can be supported with respect to the frame body portion 21 by the connection portion 4 including the fabric.
  • the engine-generator unit connecting portion 41 is located inside the frame main body portion 21 rather than the frame connecting portion 42.
  • a plurality of connecting portions 4 extend in different directions between the engine generator unit 3 and the frame main body portion 21 .
  • the fibers extend, for example, in the longitudinal direction. Therefore, at least some of the connecting portions 4 of the plurality of connecting portions 4 include fabrics in which fibers extend in different directions in plan view of the aircraft 1 .
  • the engine-generator unit 3 is connected to the body frame 2 via a connecting portion 4 including a fabric having fibers extending in different directions in a plan view of the aircraft 1 .
  • the engine-generator unit 3 can be connected with higher strength to the body frame 2 via the connecting portion 4 including the fabric with fibers extending in different directions in plan view of the aircraft 1 .
  • the connecting portion 4 including fabrics with fibers extending in different directions in a plan view of the aircraft 1 can absorb vibrations caused by the driving of the engine-generator unit 3, and the connecting portion 4 can be made of metal or the like. In comparison, the aircraft 1 can be made lighter.
  • connection part 4 In a state in which the engine-generator unit 3 is supported with respect to the frame main body 21 by the connection part 4, the natural frequency of the connection part 4 including the fabric woven with a plurality of fibers is generated by driving the engine-generator unit 3. lower than the frequency of vibration.
  • the natural frequency fe (Hz) of the connecting portion 4 can be obtained.
  • the connecting portion 4 has the effect of suppressing the transmission of vibration generated by driving the engine generator unit 3.
  • the engine-generator unit 3 is suspended from the frame main body 21 via the connecting portion 4. Therefore, during flight of the aircraft 1 , a tensile force due to the load of the engine-generator unit 3 is generated in the connecting portion 4 .
  • the connecting portion 4 extends from the frame main body portion 21 to the engine generator unit 3 in a direction inclined with respect to the vertical direction. That is, when the aircraft 1 is in flight, the connecting portion 4 extends inward from the frame body portion 21 in a plan view of the aircraft 1 .
  • In-flight of the flying object 1 means a state in which the load of the engine-generator unit 3 causes a tensile force to the connecting portion 4 due to the flying object 1 floating up, as shown in FIG. 2, for example.
  • the shortest distance L between the engine-generator unit connection portion 41 and the frame connection portion 42 of the connecting portion 4 is the horizontal direction between the engine-generator unit connection portion 41 and the frame connection portion 42.
  • the engine-generator unit 3 is supported with respect to the frame main body 21 so as to be larger than the distance D of .
  • the spring constant K of the connection portion 4 including the fabric in which a plurality of fibers are woven is determined by the shortest distance L between the engine-generator unit connection portion 41 and the frame connection portion 42. It can be smaller than the spring constant equal to the horizontal distance D to the portion 42 . Therefore, the natural frequency fe of the connecting portion 4 can be made lower than the frequency of vibration caused by driving the engine generator unit 3 . Therefore, the connecting portion 4 can effectively absorb vibrations caused by driving the engine generator unit 3 .
  • the engine-generator unit 3 is connected to the fuselage frame 2 by the connection part 4 including fabric such that the engine-generator unit connection part 41 is positioned below the frame connection part 42.
  • the engine-generator unit 3 can be connected to the body frame 2 by means of the connecting portion 4 including a fabric woven with a plurality of fibers.
  • the connecting portion 4 including the fabric can absorb the vibration caused by the driving of the engine-generator unit 3, and the weight of the aircraft 1 can be reduced as compared with the case where the connecting portion is made of metal or the like.
  • the aircraft 1 includes an electric motor 51 and a propeller 52 that is rotationally driven by the electric motor 51, and includes a plurality of rotors 5 that generate lift, and electric power that is supplied to the electric motors 51 in the plurality of rotors 5, respectively.
  • an engine-generator unit 3 that generates a power
  • a fuselage frame 2 that supports a plurality of rotors 5 and the engine-generator unit 3
  • a plurality of connecting portions 4 that connect the engine-generator unit 3 and the fuselage frame 2.
  • Each of the plurality of connecting portions 4 has a natural frequency lower than the excitation frequency generated by driving the engine-generator unit 3 when the engine-generator unit 3 is supported on the body frame 2 . As such, it includes a fabric in which multiple fibers are woven.
  • the engine-generator unit 3 is connected to the body frame 2, and the natural frequency of the connection part 4 in a state in which the engine-generator unit 3 is supported on the body frame 2 is vibration generated by driving the engine-generator unit 3. Vibration generated by driving the engine-generator unit 3 can be suppressed from being transmitted to the body frame 2 by the connecting portion 4 including a fabric in which a plurality of fibers are woven so as to be lower than the frequency.
  • the connecting portion 4 since the connecting portion 4 includes a fabric woven with a plurality of fibers, the connecting portion 4 can be configured with a higher degree of freedom in design than when the connecting portion is made of metal or the like. can be made lighter.
  • the woven fabric constituting at least part of the connecting part 4 is woven with a plurality of fibers so as to be relatively displaceable so that at least part of the vibration of the engine generator unit 3 is damped.
  • the coupling part 4 allows effective damping.
  • the weight of the aircraft 1 can be reduced as compared with the case where the connecting portion is made of metal or the like. .
  • the aircraft 1 has at least three connecting parts 4 .
  • the engine generator unit 3 is connected to the body frame 2 via at least three connecting portions 4 .
  • the engine-generator unit 3 can be connected in a more stable posture to the body frame 2 by means of at least three connecting portions 4 each including fabric.
  • the at least three connecting portions 4, each of which is made of fabric can absorb vibrations caused by the driving of the engine-generator unit 3, and the weight of the flying object 1 can be reduced as compared with the case where the connecting portions 4 are made of metal or the like. can do.
  • the engine-generator unit 3 can be more reliably connected to the airframe 2, and the vibration caused by the driving of the engine-generator unit 3 can be more effectively absorbed, and the aircraft 1 is lightweight. configuration can be realized.
  • the woven fabric included in each of the plurality of connecting portions 4 includes a woven fabric in which fibers whose base material is mainly composed of an organic substance are woven.
  • the engine-generator unit 3 can be more reliably connected to the frame by the connecting portion 4 including the fabric.
  • connection portion 4 including the fabric woven with fibers whose base material is mainly composed of organic matter can absorb the vibration caused by the driving of the engine generator unit 3, and when the connection portion is made of metal or the like.
  • the weight of the flying object 1 can be reduced as compared with .
  • the engine-generator unit 3 can be more reliably connected to the fuselage frame 2, and the configuration of the aircraft 1 that is capable of absorbing vibrations generated by driving the engine-generator unit 3 and is lightweight is realized. can do.
  • FIG. 3 is a plan view showing a schematic configuration of an aircraft 101 according to Embodiment 2.
  • FIG. 4 is a side view showing a schematic configuration of an aircraft 101 according to Embodiment 2.
  • FIG. The configuration of the aircraft 101 according to the second embodiment differs from the configuration of the aircraft 1 according to the first embodiment in the configuration of the body frame 102, the number of rotors 5, and the like.
  • configurations similar to those of the first embodiment are denoted by the same reference numerals, descriptions thereof are omitted, and only portions different from the first embodiment are described.
  • the body frame 102 has a frame body portion 121 and a plurality of rotor support portions 126.
  • the frame main body 121 has a first annular frame 122 , a second annular frame 123 , and a plurality of struts 124 connecting the first frame 122 and the second frame 123 .
  • the first frame 122 and the second frame 123 are hexagonal in plan view.
  • the first frame 122 and the second frame 123 are arranged such that their centers, sides and vertices overlap each other in plan view. Opposing vertices of the first frame 122 and the second frame 123 are connected to each other by supports 124 .
  • the frame body portion 121 is formed in a hexagonal prism shape.
  • the strut 124 extends vertically.
  • the rotor support portion 126 supports the rotor 5.
  • the rotor support portion 126 has six support arms 127 and six rib members 128 .
  • a base end of each support arm 127 is connected to each vertex of the second frame 123 of the frame main body 121 .
  • Each support arm 127 is arranged to radially extend from each vertex of the second frame 123 .
  • Each support arm 127 is supported by the frame main body 121 via each rib member 128 .
  • the tip of the rib member 128 is connected to the central portion of the support arm 127 in the longitudinal direction.
  • the base end of the rib member 128 is connected to the vertex of the first frame 122 facing the vertex of the second frame 123 to which the support arm 127 is connected. Note that each support arm 127 does not have to be supported by the frame main body 121 via the rib member 128 .
  • the rotors 5 are provided on the support arms 127 of the rotor support portion 126 respectively.
  • the rotor 5 has an electric motor 51 , a propeller 52 and a power conversion device 53 .
  • the electric motor 51 is provided at a portion of the support arm 127 to which the rib member 128 is connected. That is, the electric motor 51 is supported by the support arm 127 and the rib member 128 .
  • the rotor 5 By rotating the propeller 52 with the electric motor 51 , the rotor 5 generates lift in the axial direction of the strut 124 of the frame main body 121 .
  • the power conversion device 53 is fixed to the support arm 127.
  • the power conversion device 53 is arranged at a position through which the downwash of the propeller 52 (the air current that blows downward when the propeller 52 rotates) passes. Thereby, the power conversion device 53 is cooled by the downwash.
  • the flying object control device 6 is supported by the flying object control device support section 107 .
  • the aircraft control device support section 107 has four support legs 171 and a mounting plate 172 .
  • Each of the four support legs 171 is connected to the apex of the first frame 122 of the frame main body 121 .
  • the four support legs 171 are connected to the adjacent support legs 171 or the first frame 122 so as to form a truss structure.
  • the flying object control device support section 107 has a support rigidity capable of suppressing vibrations transmitted to the flying object control device 6 .
  • the configuration of the aircraft control device support section is not limited to the configuration described above, and any configuration that can support the aircraft control device 6 so as to suppress vibration transmitted to the aircraft control device 6 can be used. It may be a configuration. That is, the aircraft control device support section may have three or less or five or more support legs, and may not have a truss structure. Further, the aircraft control device support section may have a plate-like member, a net-like member, and the like.
  • the mounting plate 172 is a rectangular plate-like member and supported by four support legs 171 .
  • the aircraft control device 6 is fixed to the mounting plate 172 .
  • the mounting plate 172 is positioned at the center of the frame main body 121 in plan view of the aircraft 1 .
  • each of the plurality of connecting portions 4 is configured such that the natural frequency of the connecting portions 4 when the engine-generator unit 3 is supported on the body frame 102 is driven by the engine-generator unit 3 . It contains a fabric in which a plurality of fibers are woven so that it is lower than the excitation frequency that occurs.
  • the shortest distance L between the engine-generator unit connection portion 41 and the frame connection portion 42 of the connecting portion 4 is The engine-generator unit 3 is supported with respect to the frame main body 121 so as to be larger than the horizontal distance D between the machine unit connecting portion 41 and the frame connecting portion 42 .
  • the engine-generator unit 3 is configured so that the engine-generator unit connecting portion 41 is positioned below the frame connecting portion 42 during flight of the aircraft 101 . In addition, it is connected to the body frame 102 by the connection part 4 containing fabric.
  • the flying object 1 has four rotors 5 .
  • the aircraft may have three or fewer rotors, or five or more rotors.
  • the flying object 101 has six rotors 5 .
  • the aircraft may have less than 5 rotors or more than 7 rotors.
  • the aircraft 1 and 101 may have a grounding portion for landing under the engine generator unit 3 .
  • a grounding portion 208 is fixed to the lower portion of the engine generator unit 3 . Accordingly, when the flying object 201 is not in flight, the grounding portion 208 is in contact with the ground or the like. Therefore, the engine generator unit 3 can be prevented from coming into direct contact with the ground or the like.
  • the engine-generator unit 3 is connected to the body frame 2 by the connection part 4 including the fabric. Therefore, even if the airframe 2 lands at an angle to the ground when the flying object 1 lands or if the flying object 201 lands on an uneven ground, the bending of the connecting portion 4 will cause the engine generator to operate. Multiple locations of the grounding portion 208 can be grounded before the load of the entire unit 3 is applied to the grounding portion 208 . As a result, the local impact input to the ground portion 208 is mitigated. Therefore, by connecting the engine-generator unit 3 and the body frame 2 with the connecting part 4 as described above, the weight of the aircraft 201 can be reduced while reducing damage to the grounding part 208 and damage to the body frame 2. can be done.
  • ground portion 208 may function as a payload support.
  • a payload support section may be provided at the bottom of the engine generator unit 3 separately from the ground section 208 .
  • Air vehicle 201 may have a payload support section separate from ground section 208 .
  • the weight of the fuselage frame 2 can be reduced. A position can support the load. As a result, the movement performance of the flying object 201 can be improved by centralizing the mass.
  • the ground part 208 may have any shape as long as it can support the engine generator unit 3 on the ground or the like.
  • a grounding portion 308 is fixed to the lower portion of the engine generator unit 3 .
  • the grounding portion 308 is grounded when the aircraft 301 is landing. Therefore, it is possible to prevent the engine generator unit 3 from being grounded.
  • the connecting portion 4 including the fabric in which a plurality of fibers are woven is bent, so that the frame grounding portion 309 positioned below the frame body portion 121 is grounded. Therefore, the body frame 102 can be supported on the ground or the like by the frame contact portion 309 .
  • the lower end of the ground contact portion 308 is positioned below the lower end of the frame contact portion 309 during flight of the aircraft 301 .
  • the engine-generator unit 3 is connected to the machine body frame 2 by the connecting part 4 including the fabric, like the configuration shown in FIG. , the weight of the aircraft 301 can be reduced. Moreover, when the connection portion 4 is bent due to the grounding of the grounding portion 308 as described above, the frame grounding portion 309 of the frame body portion 121 is also grounded. Therefore, it is possible to make the ground portion 308 simple and lightweight.
  • ground portion 308 may function as a payload support portion.
  • a payload support section may be provided at the bottom of the engine generator unit 3 separately from the ground section 308 .
  • Air vehicle 301 may have a payload support section separate from ground section 308 .
  • the weight of the fuselage frame 102 can be reduced. A position can support the load. As a result, the movement performance of the flying object 301 can be improved by centralizing the mass.
  • the engine generator unit 3 is supported by the four connecting portions 4 with respect to the frame body portions 21 and 121 of the body frames 2 and 102 .
  • the engine-generator unit may be supported by three or less or five or more connections to the frame body.
  • the plurality of connecting parts may be arranged parallel to each other or may be arranged so as to intersect with each other in a plan view of the aircraft.
  • the plurality of connecting parts may be arranged like crossing when the aircraft is viewed from above.
  • FIG. 7 shows a schematic configuration of the flying object 401 when a plurality of connecting parts 4 are arranged like crossing in plan view of the flying object 401 .
  • the same reference numerals are assigned to the same configurations as in the first embodiment, and the following description is omitted.
  • illustration of the aircraft control device and the aircraft control device support section is omitted for explanation.
  • the flying object 401 has, for example, 12 connecting parts 4.
  • the twelve connecting portions 4 include six pairs of connecting portions 4 .
  • One end of the pair of connecting portions 4 is connected to the frame body portion 21 at the same position in the circumferential direction.
  • the pair of connecting parts 4 are arranged so that the distance between them widens from one end to the other end in a plan view of the flying object 401 .
  • the other end of the pair of connecting portions 4 is connected to the engine-generator unit 3 while vertically overlapping one of the other pair of connecting portions 4 .
  • the plurality of connecting portions 4 support the engine-generator unit 3 with respect to the frame main body portion 21 in a state in which two connecting portions 4 partially overlap each other in the thickness direction.
  • the configuration of crossing the connecting portion 4 as described above may be applied to a flying object having another configuration such as the flying object 101 of the second embodiment.
  • another damping mechanism may be provided in the portion where the connecting portion 4 overlaps in the thickness direction as described above.
  • a contact portion made of a material having a large coefficient of friction and damping (such as rubber) may be provided in the portion where the connecting portion 4 overlaps in the thickness direction.
  • the damping mechanism may be provided in a portion where the connecting portion 4 does not overlap in the thickness direction.
  • the damping mechanism may be provided in the connecting portion 4 in a configuration in which a portion of the connecting portion 4 does not overlap in the thickness direction.
  • the connecting portion 4 is a woven fabric in which a plurality of fibers are woven, and is, for example, a strip-shaped belt.
  • the connecting portion may be in the form of a string, a rope, or the like, as long as it is a woven fabric.
  • at least some of the plurality of connecting portions may have the same direction in which the fibers extend in a plan view of the aircraft.
  • a base material of the fiber may be mainly composed of a material other than an organic substance.
  • the fiber may contain a material other than an organic substance in the base material.
  • the engine-generator unit 3 has the shortest distance L between the engine-generator unit connection portion 41 and the frame connection portion 42 during flight of the aircraft 1, 101. It is connected to the fuselage frame 2 by the connection part 4 including the fabric so that the distance D in the horizontal direction to the frame connection part 42 is larger.
  • the shortest distance between the engine-generator unit connection and the frame connection is the same as the horizontal distance between the engine-generator unit connection and the frame connection during flight of the aircraft. It may be connected to the body frame by a connecting part so as to be.
  • the engine-generator unit may be supported in any posture on the body frame by the connecting portion. As long as the connecting portion can support the engine generator unit with respect to the body frame, the extending direction of the connecting portion is not limited to the extending direction of the connecting portion in each of the above-described embodiments.
  • the engine-generator unit 3 has a connection portion including fabric so that the engine-generator unit connection portion 41 is positioned below the frame connection portion 42 during flight of the aircraft 1, 101. 4 to the fuselage frame 2,102.
  • the engine-generator unit is coupled to the airframe by a coupling such that the engine-generator unit connection is at or above the frame connection during flight of the aircraft. may be
  • the frame main body 121 is formed in a hexagonal prism shape by a plurality of first frame bodies 122, a plurality of second frame bodies 123, and a plurality of struts 124.
  • the frame main body may have other shapes such as a columnar shape, other polygonal columnar shapes, and a spherical shape. At least part of the frame main body may be configured by a plate-like member.
  • Aircraft 2 1, 101, 201, 301, 401 Aircraft 2, 102 Airframe frame (frame) 3 Engine Generator Unit 4 Connection Portion 5 Rotor 6 Airplane Control Device 7, 107 Airplane Control Device Supporting Portion 21, 121 Frame Body Portion 26, 126 Rotor Supporting Portion 31 Generator 32 Power Generation Engine 41 Engine Generator Unit Connecting Portion 42 Frame connection part 51 Electric motor 52 Propeller 53 Power conversion device 71, 171 Support legs 72, 172 Mounting plate 122 First frame 123 Second frame 124 Strut 127 Support arm 128 Rib members 208, 308 Ground part 309 Frame ground part

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  • Engineering & Computer Science (AREA)
  • Aviation & Aerospace Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Remote Sensing (AREA)
  • Connection Of Motors, Electrical Generators, Mechanical Devices, And The Like (AREA)

Abstract

L'invention concerne une conception d'un aéronef, la conception étant légère et apte à absorber les vibrations générées par l'attaque d'une unité génératrice de moteur. Un aéronef (1) comprend : une pluralité de rotors (5) qui produisent une portance et comprennent des moteurs électriques (51) et des hélices (52) ; une unité génératrice de moteur qui génère de l'énergie électrique fournie à chacun des moteurs électriques (51) ; une cellule (2) qui soutient la pluralité de rotors (5) et l'unité génératrice de moteur (3) ; et une pluralité d'unités de couplage (4) qui couplent l'unité génératrice de moteur (3) et la cellule (2) l'une à l'autre. Chacune de la pluralité d'unités de couplage comprend (4) un matériau tissé dans lequel une pluralité de fibres sont tissées de telle sorte que la fréquence naturelle de l'unité de couplage (4) est inférieure à la fréquence d'excitation générée par l'attaque de l'unité génératrice de moteur (3) dans l'état dans lequel les unités de couplage (4) soutiennent l'unité génératrice de moteur (3) sur la cellule (2).
PCT/JP2021/015968 2021-04-20 2021-04-20 Aéronef WO2022224331A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
JP2021576080A JP7081060B1 (ja) 2021-04-20 2021-04-20 飛行体
PCT/JP2021/015968 WO2022224331A1 (fr) 2021-04-20 2021-04-20 Aéronef

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/JP2021/015968 WO2022224331A1 (fr) 2021-04-20 2021-04-20 Aéronef

Publications (1)

Publication Number Publication Date
WO2022224331A1 true WO2022224331A1 (fr) 2022-10-27

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JP (1) JP7081060B1 (fr)
WO (1) WO2022224331A1 (fr)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101876346B1 (ko) * 2018-01-24 2018-07-10 (주) 에이티디랩 무인 비행체
US20190256218A1 (en) * 2018-02-17 2019-08-22 Juan Manuel CORREA HAMILL Transmission system for aircraft structure
CN210133292U (zh) * 2018-12-18 2020-03-10 广州市华科尔科技股份有限公司 一种植保无人机的减震组件
JP2020100387A (ja) * 2018-12-21 2020-07-02 株式会社プロドローン 無人航空機
JP2020183210A (ja) * 2019-05-09 2020-11-12 愛三工業株式会社 マルチコプタ

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3568354B1 (fr) * 2017-01-10 2023-03-15 Aurora Flight Sciences Corporation Dispositif d'élévation verticale par propulsion hybride en série
JP7229874B2 (ja) * 2019-02-07 2023-02-28 愛三工業株式会社 マルチコプタ
CN211893633U (zh) * 2020-03-05 2020-11-10 无锡智上新材料科技有限公司 一种碳纤维无人机

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101876346B1 (ko) * 2018-01-24 2018-07-10 (주) 에이티디랩 무인 비행체
US20190256218A1 (en) * 2018-02-17 2019-08-22 Juan Manuel CORREA HAMILL Transmission system for aircraft structure
CN210133292U (zh) * 2018-12-18 2020-03-10 广州市华科尔科技股份有限公司 一种植保无人机的减震组件
JP2020100387A (ja) * 2018-12-21 2020-07-02 株式会社プロドローン 無人航空機
JP2020183210A (ja) * 2019-05-09 2020-11-12 愛三工業株式会社 マルチコプタ

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