CN111762313A - Fixed-pitch tandem electric unmanned helicopter - Google Patents

Fixed-pitch tandem electric unmanned helicopter Download PDF

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Publication number
CN111762313A
CN111762313A CN202010697471.8A CN202010697471A CN111762313A CN 111762313 A CN111762313 A CN 111762313A CN 202010697471 A CN202010697471 A CN 202010697471A CN 111762313 A CN111762313 A CN 111762313A
Authority
CN
China
Prior art keywords
unmanned helicopter
pitch
rotor
devices
rotating shaft
Prior art date
Legal status (The legal status 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 status listed.)
Withdrawn
Application number
CN202010697471.8A
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Chinese (zh)
Inventor
张森悦
李一波
刘佰仑
郭晓楠
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Huai'an Aviation Industry Research Institute Co ltd
Original Assignee
Huai'an Aviation Industry Research Institute Co ltd
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.)
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Publication date
Application filed by Huai'an Aviation Industry Research Institute Co ltd filed Critical Huai'an Aviation Industry Research Institute Co ltd
Priority to CN202010697471.8A priority Critical patent/CN111762313A/en
Publication of CN111762313A publication Critical patent/CN111762313A/en
Withdrawn legal-status Critical Current

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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B64AIRCRAFT; AVIATION; COSMONAUTICS
    • B64CAEROPLANES; HELICOPTERS
    • B64C27/00Rotorcraft; Rotors peculiar thereto
    • B64C27/04Helicopters
    • B64C27/08Helicopters with two or more rotors
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B64AIRCRAFT; AVIATION; COSMONAUTICS
    • B64CAEROPLANES; HELICOPTERS
    • B64C25/00Alighting gear
    • B64C25/32Alighting gear characterised by elements which contact the ground or similar surface 
    • B64C25/52Skis or runners
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B64AIRCRAFT; AVIATION; COSMONAUTICS
    • B64CAEROPLANES; HELICOPTERS
    • B64C27/00Rotorcraft; Rotors peculiar thereto
    • B64C27/04Helicopters
    • B64C27/12Rotor drives
    • B64C27/14Direct drive between power plant and rotor hub
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B64AIRCRAFT; AVIATION; COSMONAUTICS
    • B64CAEROPLANES; HELICOPTERS
    • B64C27/00Rotorcraft; Rotors peculiar thereto
    • B64C27/32Rotors
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B64AIRCRAFT; AVIATION; COSMONAUTICS
    • B64CAEROPLANES; HELICOPTERS
    • B64C39/00Aircraft not otherwise provided for
    • B64C39/02Aircraft not otherwise provided for characterised by special use
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B64AIRCRAFT; AVIATION; COSMONAUTICS
    • B64UUNMANNED AERIAL VEHICLES [UAV]; EQUIPMENT THEREFOR
    • B64U10/00Type of UAV
    • B64U10/10Rotorcrafts
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B64AIRCRAFT; AVIATION; COSMONAUTICS
    • B64UUNMANNED AERIAL VEHICLES [UAV]; EQUIPMENT THEREFOR
    • B64U50/00Propulsion; Power supply
    • B64U50/10Propulsion
    • B64U50/19Propulsion using electrically powered motors

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  • Engineering & Computer Science (AREA)
  • Aviation & Aerospace Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Remote Sensing (AREA)
  • Toys (AREA)

Abstract

The invention discloses a fixed-pitch tandem electric unmanned helicopter.A rotor wing device is respectively arranged at the front end and the rear end of a helicopter body, the counter torque can be offset through the reverse rotation of the two rotor wing devices, a tail rotor structure is not required to be arranged, so that the unmanned helicopter has a simple and compact structure, the tail rotor structure is omitted, the eddy current influence caused by the tail rotor can be avoided, and the pneumatic efficiency of the unmanned helicopter is improved; the propeller in the unmanned aerial vehicle adopts fixed pitch and electric speed regulation to realize total pitch control; the front and rear power devices are motors arranged on the machine body, the motors adopt electronic speed regulation, and the lift force is regulated by regulating the rotating speed to realize up-and-down motion; the propellers generate inclination angles through a multi-blade propeller and a swash plate-free mode with a shaft capable of horizontally rotating, so that the forward and backward movement is realized; the fixed-pitch tandem electric unmanned helicopter has the advantages of simple structure, reasonable design, convenience in control, low failure rate and the like.

Description

Fixed-pitch tandem electric unmanned helicopter
Technical Field
The invention relates to the technical field of unmanned aerial vehicles, in particular to a fixed-pitch tandem electric unmanned helicopter.
Background
Because unmanned helicopter not only can VTOL, free hover, time of endurance and flying speed are more moderate again moreover, consequently, can be used to the application of intermediate range scene, if: island transportation, aerial geophysical prospecting, rescue and disaster relief and the like. However, most unmanned helicopters have certain problems, such as difficult control and high requirements on flight control and control personnel. In addition, most unmanned helicopters at present all install the tail-rotor on unmanned aerial vehicle in order to balance the reaction torque that main rotor produced, because the setting of tail-rotor not only makes unmanned helicopter's mechanical efficiency reduce, easily receives the crosswind interference moreover, the fuselage is too long and narrow, the afterbody fault rate is high, and the balancing process is loaded down with trivial details, the plug is easily received the undercarriage interference, has numerous problems. For example: the single-rotor tail rotor type unmanned helicopter which is common in China has the advantages that the volume of the whole helicopter is large due to the existence of the tail rotor, and the helicopter threatens ground operators and is easy to collide with obstacles; because the tail rotor is influenced by the eddy currents of the main rotor and the tail of the aircraft body, the aerodynamic efficiency is low, the load and vibration of the tail rotor are large, and the tail rotor is sensitive to crosswind during hovering.
In addition, the traditional helicopter is characterized in that the swash plate is adopted, the blades are driven to incline through the inclination of the swash plate, and pressure difference is generated on two sides of each blade, so that forward and backward directional forces are generated, but the structure of the swash plate is complex, the manufacturing cost is high, and the failure rate is high.
Therefore, how to develop a novel unmanned helicopter to solve the problems of the existing unmanned helicopter becomes a problem to be solved urgently.
Disclosure of Invention
In view of the above, the invention provides a fixed-pitch tandem electric unmanned helicopter, which at least solves the problems of low aerodynamic efficiency, high failure rate and the like of the conventional unmanned helicopter.
The invention provides a technical scheme, in particular to a fixed-pitch tandem electric unmanned helicopter, which comprises: the aircraft comprises an airframe, a controller, two rotor wing devices and two power devices;
the two rotor wing devices are respectively and symmetrically arranged at the front end and the rear end of the fuselage;
each of the rotor devices includes: the device comprises a rotating shaft, a propeller, a rotating ring, a steering engine and a ball head connecting rod;
the rotating shaft penetrates through the upper plate of the machine body in a rotating mode, the upper end of the rotating shaft is located above the outer portion of the machine body, and the lower end of the rotating shaft is located inside the machine body;
the propeller is positioned above the machine body and fixedly connected with the upper end of the rotating shaft, and the propeller is a fixed-distance propeller;
the rotating ring is rotatably sleeved outside the rotating shaft;
the steering engine is fixedly arranged on the machine body and positioned on the front side or the rear side of the rotating shaft, and an output shaft of the steering engine vertically extends upwards;
the connecting rod end of the ball head connecting rod is fixedly connected with the movable ring, and the ball head end of the ball head connecting rod is connected with the output shaft of the steering engine;
the power devices correspond to the rotor wing devices one by one, each power device is fixedly arranged in the machine body, and the output end of each power device is in driving connection with the lower end of the rotating shaft;
the controller set up in the inside of fuselage, just the output of controller respectively with every the control end of steering wheel and every among the rotor device the control end of power device is connected.
Preferably, the body includes: the landing gear comprises an upper plate, a lower plate, two side plates and two landing gears;
the two side plates are arranged in parallel at intervals, and a U-shaped groove which is sunken downwards is formed in the upper edge of each side plate;
the upper plate is connected with the upper edges of the two side plates in a plugging manner;
the lower plate is connected to the lower edges and two sides of the two side plates in a plugging manner;
two undercarriage interval parallel arrangement, and every the upper end of undercarriage all with hypoplastron fixed connection.
Preferably, the upper plate, the lower plate and the two side plates in the machine body are made of aluminum alloy materials.
Further preferably, the landing gear in the fuselage is an aluminum alloy frame or a carbon fiber frame.
Further preferably, each propeller in the rotor apparatus has 4 blades.
Further preferably, the distance between the centers of the two rotor devices is larger than the diameter of the rotor devices.
Preferably, each power device is a speed-adjustable motor.
According to the fixed-pitch tandem type electric unmanned helicopter provided by the invention, the front end and the rear end of the helicopter body are respectively provided with the rotor wing devices, the counter torque can be mutually offset through the reverse rotation of the two rotor wing devices, a tail rotor structure is not required to be arranged, so that the unmanned helicopter has a simple and compact structure, and the tail rotor structure is omitted in the unmanned helicopter, so that the eddy current influence caused by the tail rotor can be avoided, and the pneumatic efficiency of the unmanned helicopter is further improved; above-mentioned two rotor devices symmetry sets up both ends around the fuselage, not only makes the volume increase of fuselage, allows the focus to have a great range removal moreover, need not special balancing, has the advantage that loads, conveying efficiency are high. In addition, the rotor device in the unmanned helicopter adopts a swash plate-free mode, the inclination control of a rotating shaft is realized through the mutual matching of a steering engine, a ball head connecting rod and a movable ring, and then the propeller generates an inclination angle, so that forward or backward force is generated, the forward and backward flight direction control is realized, and the lifting of the unmanned helicopter can realize the lifting control only by controlling the rotating speeds of two rotor devices, so that the difficulty coefficient of the control is greatly reduced. Because the structure design of the unmanned helicopter simultaneously cancels the complicated mechanical structures of the tail rotor and the swash plate, the failure rate of the unmanned helicopter can be greatly reduced.
The fixed-pitch tandem electric unmanned helicopter provided by the invention has the advantages of simple structure, reasonable design, convenience in control, low failure rate and the like.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and together with the description, serve to explain the principles of the invention.
In order to more clearly illustrate the embodiments or technical solutions in the prior art of the present invention, the drawings used in the description of the embodiments or prior art will be briefly described below, and it is obvious for those skilled in the art that other drawings can be obtained based on these drawings without creative efforts.
Fig. 1 is a schematic structural view of a fixed-pitch tandem electric unmanned helicopter provided in the disclosed embodiment of the invention;
fig. 2 is a schematic structural diagram of a fuselage of a fixed-pitch tandem electric unmanned helicopter according to an embodiment of the present disclosure;
fig. 3 is a schematic structural diagram of a rotor device in a fixed-pitch tandem electric unmanned helicopter according to an embodiment of the present disclosure.
Detailed Description
Reference will now be made in detail to the exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, like numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Rather, they are merely examples of apparatus consistent with certain aspects of the invention, as detailed in the appended claims.
In order to solve the problems of low aerodynamic efficiency and high failure rate of the conventional unmanned helicopter, the embodiment provides a fixed-pitch tandem electric unmanned helicopter, which is mainly composed of a fuselage 1, a controller, two rotor wing devices 2 and two power devices 3, as shown in fig. 1, wherein the two rotor wing devices 2 are respectively and symmetrically arranged at the front end and the rear end of the fuselage 1, as shown in fig. 3, each rotor wing device 2 is composed of a rotating shaft 21, a propeller 22, a movable ring 23, a steering engine 24 and a ball connecting rod 25, wherein the rotating shaft 21 passes through an upper plate of the fuselage 1 in a rotating way, the upper end of the rotating shaft is positioned above the exterior of the fuselage 1, the lower end of the rotating shaft is positioned inside the fuselage 1, the propeller 22 is positioned above the fuselage 1 and fixedly connected with the upper end of the rotating shaft 21, the propeller 22 is a fixed-distance propeller, the movable ring 23 is rotatably sleeved outside the rotating shaft 21, the steering engine, the front side or the rear side of the rotating shaft 21 is located, an output shaft of the steering engine 24 vertically extends upwards, a connecting rod end of a ball connecting rod 25 is fixedly connected with the rotating ring 23, a ball end of the ball connecting rod 25 is connected with an output shaft of the steering engine 24, the power devices 3 correspond to the rotor wing devices 2 one to one, each power device is fixedly arranged in the machine body 1, an output end of each power device 3 is connected with a lower end of the rotating shaft 21 in a driving mode, the controller is arranged in the machine body 1, an output end of the controller is connected with a control end of the steering engine 24 in each rotor wing device 2 and a control end of each power device 3 respectively, the steering engine 24 and the power devices 3 are controlled to move respectively, and the power devices 3 can select speed regulating motors.
Compared with other types of unmanned aerial vehicles, the fixed-pitch tandem electric unmanned helicopter provided by the embodiment has the advantages that the size of the helicopter body is small, the structure is simple, the pneumatic efficiency is high, the control complexity can be greatly reduced due to the adoption of the fixed-pitch propellers, and the two rotor wing devices are arranged in tandem relative to the helicopter body, so that the overall size of the helicopter body is smaller than that of single-rotor wing-with-tail-propeller helicopters, double-rotor wing transverse helicopters and multi-rotor wing helicopters; compared with the same conventional unmanned helicopter with the rotor wing provided with the tail rotor, the unmanned helicopter has the advantages that the power loss is reduced, the power is relatively rich, the crosswind resistance is high, and the load is relatively high due to the absence of the tail rotor; the swash plate-free double-shaft mode can reduce the complexity of the system, the power and operation of the double-rotor helicopter adopt an electric mode, a large-size engine, a complex transmission system and the like are omitted, the space of the helicopter body is greatly saved, the reliability is improved, and more task equipment such as a pesticide spraying box and the like can be carried in the saved space of the helicopter body.
The tandem electric unmanned helicopter with the fixed pitch in the embodiment can respectively realize lifting motion and back-and-forth motion, wherein the lifting motion is mainly realized by controlling the rotating speed of the power device through the controller, further controlling the rotating speeds of the rotating shaft and the propeller, further realizing the lifting motion of the unmanned helicopter, specifically, when the controller controls the rotating speed of the power device to increase, the lifting motion of the unmanned helicopter can be realized, and when the controller controls the rotating speed of the power device to decrease, the descending motion of the unmanned helicopter can be realized; the back and forth movement mainly is upwards stretched out or is withdrawed downwards through the output shaft of controller control steering wheel, transmission through bulb connecting rod and rotating ring for the pivot takes place to incline, and then drive the screw and produce the angle, and then make unmanned helicopter have the power of advancing or retreating, and then carry out the back and forth movement, particularly, suppose that the output shaft of steering wheel upwards stretches out, can make the pivot incline forward, the lift of screw produced forward component this moment, can realize the forward motion of unmanned helicopter, on the contrary, the output shaft of steering wheel withdraws downwards, can make the pivot incline backward, the lift of screw produced backward component this moment, can realize the backward motion of unmanned helicopter, whole control process is simple.
Referring to fig. 2, there is provided a fuselage structure for the present embodiment, the fuselage 1 is mainly composed of an upper plate 11, a lower plate 12, two side plates 13 and two landing gears 14, wherein, the two side plates 13 are arranged in parallel at intervals, the upper edge of each side plate 13 is provided with a U-shaped groove which is sunken downwards, the upper plate 11 is connected with the upper edges of the two side plates 13 in a sealing way, the lower plate 12 is connected with the lower edges and two sides of the two side plates 13 in a sealing way, the two landing gears 14 are arranged in parallel at intervals, and the upper end of each landing gear 14 is fixedly connected with the lower plate 12, wherein, in order to improve the firmness degree of the fuselage 1, a reinforcing member can be arranged between the upper plate 11 and the lower plate 12 and the two side plates 13, and the fuselage of the unmanned helicopter is shaped like a U through the structural design, or a ship shape, in which case the installation of equipment such as a navigation device, a battery, a controller, a data transmission station, and the like can be facilitated.
In order to reduce the weight of the unmanned helicopter and ensure the firmness of the unmanned helicopter, as an improvement of the technical scheme, the upper plate 11, the lower plate 12 and the two side plates 13 in the helicopter body are all made of aluminum alloy materials, and the undercarriage 14 is made of an aluminum alloy frame or a carbon fiber frame.
The propeller 22 in the above embodiment may alternatively be in the form of a multi-bladed propeller having 4 blades.
In order to avoid the mutual overlapping of the two rotor wing devices 2 on the fuselage and the influence of the generated aerodynamic interference on the flight stability and the aerodynamic efficiency of the unmanned helicopter, as an improvement of the technical scheme, the center-to-center distance between the two rotor wing devices 2 is designed to be larger than the diameter of the rotor wing devices 2.
Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the invention and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims.
It is to be understood that the present invention is not limited to what has been described above, and that various modifications and changes may be made without departing from the scope thereof. The scope of the invention is limited only by the appended claims.

Claims (7)

1. A fixed-pitch tandem electric unmanned helicopter is characterized by comprising: the aircraft comprises an airframe (1), a controller, two rotor wing devices (2) and two power devices (3);
the two rotor wing devices (2) are respectively and symmetrically arranged at the front end and the rear end of the aircraft body (1);
each rotor arrangement (2) comprises: the propeller comprises a rotating shaft (21), a propeller (22), a rotating ring (23), a steering engine (24) and a ball head connecting rod (25);
the rotating shaft (21) penetrates through the upper plate of the machine body (1) in a rotating mode, the upper end of the rotating shaft (21) is located above the outer portion of the machine body (1), and the lower end of the rotating shaft (21) is located inside the machine body (1);
the propeller (22) is positioned above the machine body (1) and is fixedly connected with the upper end of the rotating shaft (21), and the propeller (22) is a fixed-distance propeller;
the rotating ring (23) is rotatably sleeved outside the rotating shaft (21);
the steering engine (24) is fixedly arranged on the machine body (1) and is positioned on the front side or the rear side of the rotating shaft (21), and an output shaft of the steering engine (24) vertically extends upwards;
the connecting rod end of the ball head connecting rod (25) is fixedly connected with the movable ring (23), and the ball head end of the ball head connecting rod (25) is connected with the output shaft of the steering engine (24);
the power devices (3) correspond to the rotor wing devices (2) one by one, each power device (3) is fixedly arranged in the machine body (1), and the output end of each power device (3) is in driving connection with the lower end of the rotating shaft (21);
the controller is arranged in the fuselage (1), and the output end of the controller is connected with the control end of each steering engine (24) in the rotor wing device (2) and the control end of each power device (3).
2. The pitch-controlled inline electric unmanned helicopter of claim 1, wherein the main body (1) comprises: an upper plate (11), a lower plate (12), two side plates (13) and two landing gears (14);
the two side plates (13) are arranged in parallel at intervals, and a U-shaped groove which is sunken downwards is formed in the upper edge of each side plate (13);
the upper plate (11) is connected to the upper edges of the two side plates (13) in a sealing manner;
the lower plate (12) is connected to the lower edges and two sides of the two side plates (13) in a plugging manner;
the two landing gears (14) are arranged in parallel at intervals, and the upper end of each landing gear (14) is fixedly connected with the lower plate (12).
3. The pitch-controlled tandem electric unmanned helicopter according to claim 2, wherein the upper plate (11), the lower plate (12) and the two side plates (13) in the fuselage are made of an aluminum alloy material.
4. The pitch-controlled tandem electric unmanned helicopter according to claim 2, wherein the landing gear (14) in the fuselage (1) is an aluminum alloy frame or a carbon fiber frame.
5. The fixed-pitch tandem electric unmanned helicopter of claim 1, wherein the propeller (22) in each of the rotor devices (2) has 4 blades.
6. The pitch controlled tandem electric unmanned helicopter according to claim 1, wherein the center-to-center distance between the two rotor devices (2) is larger than the diameter of the rotor devices (2).
7. The fixed-pitch tandem electric unmanned helicopter according to claim 1, wherein each of the power devices (3) is a variable speed motor.
CN202010697471.8A 2020-07-20 2020-07-20 Fixed-pitch tandem electric unmanned helicopter Withdrawn CN111762313A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202010697471.8A CN111762313A (en) 2020-07-20 2020-07-20 Fixed-pitch tandem electric unmanned helicopter

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202010697471.8A CN111762313A (en) 2020-07-20 2020-07-20 Fixed-pitch tandem electric unmanned helicopter

Publications (1)

Publication Number Publication Date
CN111762313A true CN111762313A (en) 2020-10-13

Family

ID=72728573

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202010697471.8A Withdrawn CN111762313A (en) 2020-07-20 2020-07-20 Fixed-pitch tandem electric unmanned helicopter

Country Status (1)

Country Link
CN (1) CN111762313A (en)

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Application publication date: 20201013