CN108248851B - Device for protecting the rotor of an aircraft and aircraft with such a device - Google Patents
Device for protecting the rotor of an aircraft and aircraft with such a device Download PDFInfo
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- CN108248851B CN108248851B CN201810106901.7A CN201810106901A CN108248851B CN 108248851 B CN108248851 B CN 108248851B CN 201810106901 A CN201810106901 A CN 201810106901A CN 108248851 B CN108248851 B CN 108248851B
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- aircraft
- upper cover
- rotors
- rotor
- lower cover
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- 238000009434 installation Methods 0.000 claims abstract description 4
- 229920000049 Carbon (fiber) Polymers 0.000 claims description 3
- 239000004917 carbon fiber Substances 0.000 claims description 3
- 239000003365 glass fiber Substances 0.000 claims description 3
- 239000000463 material Substances 0.000 claims description 3
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 claims description 3
- 239000011347 resin Substances 0.000 claims description 3
- 229920005989 resin Polymers 0.000 claims description 3
- 230000007704 transition Effects 0.000 claims 1
- 230000000694 effects Effects 0.000 abstract description 8
- 230000009286 beneficial effect Effects 0.000 abstract description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 4
- 229910052782 aluminium Inorganic materials 0.000 description 4
- 239000004411 aluminium Substances 0.000 description 4
- 238000010586 diagram Methods 0.000 description 2
- 238000005096 rolling process Methods 0.000 description 2
- 230000000087 stabilizing effect Effects 0.000 description 2
- 238000013473 artificial intelligence Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C27/00—Rotorcraft; Rotors peculiar thereto
- B64C27/20—Rotorcraft characterised by having shrouded rotors, e.g. flying platforms
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- 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
- B64D29/00—Power-plant nacelles, fairings, or cowlings
- B64D29/02—Power-plant nacelles, fairings, or cowlings associated with wings
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- 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
- B64D29/00—Power-plant nacelles, fairings, or cowlings
- B64D29/06—Attaching of nacelles, fairings or cowlings
Landscapes
- Engineering & Computer Science (AREA)
- Aviation & Aerospace Engineering (AREA)
- Mechanical Engineering (AREA)
- Structures Of Non-Positive Displacement Pumps (AREA)
Abstract
The invention discloses a device for protecting aircraft rotors, wherein the number of the aircraft rotors is N, N is more than or equal to 2, the device comprises a lower cover provided with a motor installation position and provided with a side support plate, and the device is characterized by also comprising an upper cover arranged above the side support plate and a rectifying piece fixed in the enclosed area of the lower cover, the upper cover and the side support plate; the side supporting plate is provided with a first airflow hole; the upper cover is provided with a second airflow hole; the side of the fairing is not provided with airflow holes to distinguish airflow areas of the N rotors from each other. The beneficial effects are as follows: by adopting the rectifying piece, the dynamic effect is better on the basis of more comprehensive protection effect. The invention also discloses an aircraft, which is provided with at least two centrally symmetrical rotor wings, and the rotor wings are provided with the device. The beneficial effects are as follows: high safety and excellent dynamic effect.
Description
Technical Field
The invention relates to the technical field of aircraft rotors, in particular to a device for protecting an aircraft rotor.
The invention also relates to the technical field of rotorcraft, in particular to an aircraft with an aircraft rotor protection device.
Background
Four rotor crafts simple structure, the flight mode is nimble, has been widely used in trades such as agricultural plant protection, geological exploration, environmental protection, express delivery transportation, aerial photography at present. With the rapid development of computer technology and the application of artificial intelligence in various fields, unmanned aerial vehicles will draw more and more attention.
Although the four-rotor aircraft has a simple structure and strong maneuverability, the flight of a user without professional training still has a great safety hazard. Especially in the areas with dense crowds, once the unmanned aerial vehicle flying at high speed is out of control or falls from high altitude, the life safety and property of other people can be endangered, and unnecessary casualties and economic losses are caused.
Chinese patent document CN204846369U whose publication date is 2015, 12 months and 9 days discloses a rotor wing protection cover for a rotor wing unmanned aerial vehicle, which comprises a circular protection cover body arranged outside a substrate of the rotor wing unmanned aerial vehicle, wherein the protection cover body is provided with an airflow channel for airflow to flow between two rotor wing protection covers at a position opposite to an adjacent rotor wing protection cover body, and the rest of the side wall of the protection cover body is uniformly provided with burden reduction through holes. This technical scheme adopts the ring shape safety cover to protect the side of unmanned aerial vehicle rotor, but along with the increase of high building, unmanned aerial vehicle also can receive the influence of junk when taking off and descending and lead to the rotor rupture to lead to the flight accident.
Disclosure of Invention
The problem to be solved by the invention is to provide a device for protecting the rotor of an aircraft, which has a better dynamic effect on the basis of a more comprehensive protective effect.
In order to solve the technical problems, the invention adopts the following technical scheme:
designing a device for protecting aircraft rotors, the number of aircraft rotors being N, N ≧ 2, comprising: the motor comprises a lower cover provided with a motor mounting position and a side supporting plate, an upper cover arranged above the side supporting plate, and a rectifying piece fixed in the enclosed area of the lower cover, the upper cover and the side supporting plate; the side supporting plate is provided with a first airflow hole; the upper cover is provided with a second airflow hole; the side of the fairing is not provided with airflow holes to distinguish airflow areas of the N rotors from each other. This technical scheme adopts the upper cover to make the device form wholly, and its structural strength is higher, adopts the fairing to make the regional mutual isolation of air current of aircraft rotor, avoids in the device because of the aircraft rotor forms the turbulent flow of mutual disturbance when rotating, can influence the factor of aircraft vibration for a short time, owing to avoided the interact of aircraft, so its is efficient.
Preferably, the bottom edge configuration of the fairing comprises N arcs of equal length each with the center of the aircraft rotor as the arc center, and the radius of the arc is greater than the wing length of the aircraft rotor.
Further, the arc angle of the circular arc is 90 degrees, and the arc edges of the circular arc are connected in sequence.
Furthermore, the side surface of the rectifying piece is provided with an inward concave connecting cambered surface which is smoothly transited with the bottom edge configuration. Because the flight attitude of the aircraft comprises pitching motion and rolling motion, the airflow channel of the rotor wing with the reduced rotating speed is smaller and the airflow channel of the rotor wing with the increased rotating speed is larger when the aircraft flies in pitching mode by adopting the curved surface, and the aircraft has stabilizing effect.
Preferably, the fairing is a housing. The housing can save space and minimize the effect of its weight.
Preferably, the fairing is fixedly connected with the lower cover and the upper cover simultaneously. The rectifying piece is fixedly connected with the lower cover and the upper cover, so that the rectifying piece has supporting and connecting functions, and the weight of the device can be reduced while the strength of the device is not reduced.
Preferably, the collateral branch fagging has N, for the arc, the radian of collateral branch fagging satisfies: the contour formed when any two adjacent aircraft rotors rotate has a common tangent line, and the side support plates are arranged in the area of the sides of the two adjacent aircraft rotors with the tangent line as a boundary line.
Preferably, a top column is further arranged between the lower cover and the upper cover, and two ends of the top column are fixedly connected with the upper cover and the lower cover respectively. The top pillar is used to enhance the strength of the device.
Furthermore, the fore-set is 55mm, the external diameter is 5 mm's aluminium post for the height, the figure of aluminium post is 16, is the symmetric distribution and installs on the lower cover.
Preferably, the first airflow holes are uniformly distributed on the plate surfaces of the side supporting plates, and the second airflow holes are uniformly distributed on the upper cover plate and respectively correspond to the lower aircraft rotors.
Preferably, the lower cover plate is a carbon fiber plate with the thickness of 2 mm; the upper cover plate is a glass fiber plate with the thickness of 1.5 mm; the side supporting plate is a printing body made of arc 8500 resin material with the thickness of 1.2mm, and the radius of the arc of the side supporting plate minus the radius of the propeller is more than or equal to 24 mm.
The invention also provides an aircraft, which is provided with at least two centrally symmetrical rotor wings, and the rotor wings are provided with the device.
Compared with the prior art, the invention has the beneficial technical effects that: by adopting the rectifying piece, the dynamic effect is better on the basis of more comprehensive protection effect.
Drawings
Fig. 1 is a block diagram of a lower cover of a device for protecting the rotor of an aircraft.
Figure 2 is a block diagram of the upper cover of a device for protecting the rotor of an aircraft.
Figure 3 is a perspective view of a side support plate of a device for protecting an aircraft rotor.
Fig. 4 is a top view of fig. 3.
Figure 5 is a top view of a device for protecting the rotor of an aircraft with the upper cover removed and the holes of the lower cover not shown to clarify the structure.
Fig. 6 is a sectional view EE of fig. 5.
Figure 7 shows another configuration of a fairing for a device for protecting the rotor of an aircraft.
In the figure, 1 is a lower cover, 11 is a motor mounting position, 14 is a through hole, 15 is a lightening hole, 2 is an upper cover, 21 is a second airflow hole, 22 is a lightening hole, 24 is a through hole, 3 is a side support plate, 31 is a first airflow hole, 32 is a side support plate mounting hole, 4 is a rectifying member, 41 is a bottom edge of the rectifying member, 42 is a side surface of the rectifying member, and 43 is a top surface of the rectifying member.
Detailed Description
The following examples are intended to illustrate the present invention in detail and should not be construed as limiting the scope of the present invention in any way.
Example 1: a device for protecting aircraft rotors, the number of which is N =4, see fig. 1-7, comprising: the lower cover 1 with a motor mounting position 11 is provided with a side support plate 3, the upper cover 2 is arranged above the side support plate 3, and the rectifying piece 4 is fixed in the area enclosed by the lower cover 1, the upper cover 2 and the side support plate 3; the side supporting plate 3 is provided with a first airflow hole 31; the upper cover 2 is provided with a second air flow hole 21, and the side of the fairing 4 is not provided with air flow holes to distinguish the air flow areas of the 4 rotors from each other. For separating the airflow zones of the aircraft rotor. In this embodiment, the lower cover 1 has 4 motor installation positions 11, that is, when the lower cover is applied to a four-wing aircraft, the motor installation positions 11 can be matched with the number and positions of the rotors of the aircraft to meet the needs of the aircraft.
Fig. 1 is substantially the same as fig. 3 disclosed in CN204846369U, except that in fig. 1, the lower cover is provided with through holes 14, and the through holes 14 facilitate the use of screws for fixedly connecting the lower cover 1 and the side support plates 3 together. The lightening holes 15 are waist-shaped holes in the strip-shaped holes, and are used for lightening under the condition that the strength of the lower cover is not influenced, and used for forming fixing positions so as to be convenient for binding and fixing other equipment.
In fig. 2, the upper cover 2 is different from the lower cover 1 in that the motor mounting position 11 of the lower cover 1 is formed by three keels which are 120 ° to each other, and in the upper cover 2, the keel of the lower cover 1 is designed as follows: and a plurality of radial ribs and circumferential ribs are distributed by taking the motor mounting position 11 right below the upper cover 2 as a circle center, and gaps between the radial ribs and the circumferential ribs are second airflow holes 21.
In fig. 3-4, the side support plates 3 are 4 arc plates of 200 °, and when being installed, the side support plates 3 are installed at four corners of the lower cover 1. In this embodiment, the side supporting plate 3 may be fixedly connected to the lower cover 1 and the upper cover 2 by screws. In other embodiments, the support plate 3 may be welded to the lower cover 1 and the upper cover 2, respectively. The side support plates 3 may also be designed as members formed vertically upward along the sides of the lower cover 1, so that the integrity is better, but the manufacturing and maintenance costs are slightly higher.
In fig. 5, the base 41 of fairing 4 is configured to comprise an arc of equal length centered on the center of the aircraft rotor, respectively, and having a radius greater than the wing length of the aircraft rotor. The fairing 4 needs to be fixed in the device to prevent it from moving. In fig. 6, the side surface 42 of the fairing 4 is an inwardly concave arc surface, and in other embodiments, the side surface of the fairing 4 may be a vertical surface.
In FIG. 7, the fairing is shown with an arcuate junction at the sides and a zone of turbulence in the flow at 44, and the fairing design is not optimal.
The following focuses on the principle of the lower fairing:
in fig. 5, the rotor A, B, C, D of the four-wing aircraft is an inner two-dot chain line, and the induced airflow is an outer two-dot chain line, and the rotation direction is as shown in the figure. After setting up fairing 4, the air current of 4 rotor disturbances does not influence each other. If fairing 4 is removed, the airflow of rotor a and rotor D will collide with each other at fairing 4, and the airflow of rotor B and rotor C will collide with each other at fairing 4, which may cause vibrations. In the figure, with the side support plate 3 shown in figure 3, the air flow is unobstructed in the forward direction as it exits tangentially. In fig. 5, the side of the side support plate 3 is at a tangent to the rotor radius taken along the center line of the rotor A, D, and similarly elsewhere.
It should be understood that the present solution is not limited to four-wing aircraft, and the principle can be extended to multi-wing aircraft capable of maintaining balance, i.e. N ≧ 2.
Example 2: as an improvement to embodiment 1, a device for protecting an aircraft rotor, see fig. 1-7, the configuration of the bottom edge 41 of the fairing 4 comprises N (N =4 in this embodiment) arcs of equal length each centred on the centre of the aircraft rotor and having a radius greater than the wing length of the aircraft rotor. The arc angle of the circular arc is 90 degrees, and the arc edges of the circular arc are connected in sequence. The side faces 42 of the fairing 4 are designed as inwardly concave, curved abutment faces with a smoothly transitioning bottom edge 41 configuration and a top face with a reduced bottom edge configuration. Because the flight attitude of the aircraft comprises pitching motion and rolling motion, the airflow channel of the rotor wing with the reduced rotating speed is smaller and the airflow channel of the rotor wing with the increased rotating speed is larger when the aircraft flies in pitching mode by adopting the curved surface, and the aircraft has stabilizing effect.
Referring to fig. 6, the fairing 4 is a housing. The shell can be used for accommodating articles to save space and reduce the influence of weight as much as possible.
The rectifying piece 4 is fixedly connected with the lower cover 1 and the upper cover 2 respectively. The rectifying piece 4 is fixedly connected with the lower cover 1 and the upper cover 2, so that the rectifying piece 4 has supporting and connecting functions, and the weight of the device can be optimally reduced while the strength of the device is not reduced.
In fig. 1, a top pillar is further arranged between the lower cover 1 and the upper cover 2, and two ends of the top pillar are respectively and fixedly connected with the upper cover 2 and the lower cover 1. The top pillar is used to enhance the strength of the device. Referring to fig. 3, the top post may be provided between the side support plate mounting holes 32 in fig. 3.
In fig. 3, the first air flow openings 31 are evenly distributed on the surface of the side support plate 3, and in fig. 2, the second air flow openings 21 are evenly distributed on the upper cover plate 2 and respectively correspond to the lower aircraft rotor.
In this embodiment, the lower cover plate 1 is a carbon fiber plate with a thickness of 2 mm; the upper cover plate 2 is a glass fiber plate with the thickness of 1.5 mm; the side supporting plate 3 is a circular arc 8500 resin material printing body with the thickness of 1.2mm, and the radius of the side supporting plate 3 minus the radius of the propeller is more than or equal to 24 mm.
In this embodiment, the fore-set is 55mm, the external diameter is 5 mm's aluminium post for the height, and the upper and lower terminal surface of fore-set is equipped with the screw hole, the figure of aluminium post is 12, is the symmetric distribution and installs on the lower cover.
When the device is installed, the side supporting plate and the lower cover are fixedly connected through the top column and the screws; and (3) adhering the middle line of the fairing 4 to the upper cover through the center of the upper cover, then aligning the upper cover with the lower cover, adhering the middle line to the lower cover through the center of the lower cover, and fixedly connecting the upper cover and the side supporting plate through the matching of a screw and a top column.
Example 3: an aircraft, the aircraft has two rotors that are centrosymmetric setting at least, install the device of embodiment 1 or 2 on the rotor.
While the present invention has been described in detail with reference to the drawings and the embodiments, those skilled in the art will understand that various specific parameters in the above embodiments can be changed without departing from the spirit of the present invention, and a plurality of specific embodiments are formed, which are common variation ranges of the present invention, and will not be described in detail herein.
Claims (9)
1. A device for protecting the rotor wings of an aircraft is provided, the number of the rotor wings of the aircraft is N, N is more than or equal to 2, the device comprises a lower cover provided with a motor installation position and provided with a side support plate, and the device is characterized by also comprising an upper cover arranged above the side support plate, and a rectifying piece fixed in the enclosed area of the lower cover, the upper cover and the side support plate; the side supporting plate is provided with a first airflow hole; the upper cover is provided with a second airflow hole; the side surface of the rectifying piece is not provided with airflow holes so as to distinguish airflow areas of the N rotors from each other, the bottom edge of the rectifying piece is configured to comprise N circular arcs with equal length and taking the center of the aircraft rotor as an arc center, and the radius of each circular arc is larger than the wing length of the aircraft rotor.
2. The device of claim 1, wherein the arcs have an arc angle of 90 ° and the arc sides of the arcs meet in sequence.
3. The device of claim 1, wherein the sides of the fairing are configured as an inwardly concave, contoured surface that smoothly transitions with the base configuration.
4. The device of claim 1, wherein the fairing is a housing.
5. The apparatus of claim 1, wherein the fairing is fixedly coupled to both the lower and upper covers.
6. The device of claim 1, wherein a top column is further arranged between the lower cover and the upper cover, and two ends of the top column are respectively fixedly connected with the upper cover and the lower cover.
7. The device of claim 1, wherein the number of the side supporting plates is N, and the side supporting plates are arc-shaped, and the radian of the side supporting plates satisfies: the contour formed when any two adjacent aircraft rotors rotate has a common tangent, and the side support plates are arranged in the area of the sides of the two adjacent aircraft rotors with the tangent as a boundary line.
8. The apparatus of claim 1, wherein the lower cover is a 2mm thick carbon fiber plate; the upper cover is a glass fiber plate with the thickness of 1.5mm, and the second airflow holes are uniformly distributed on the upper cover and respectively correspond to the aircraft rotors below; the side supporting plate is a printing body made of arc 8500 resin material with the thickness of 1.2mm, and the radius of the arc of the side supporting plate minus the radius of the propeller is more than or equal to 24 mm.
9. An aircraft having at least two rotors arranged in central symmetry, characterized in that the rotors are provided with means for protecting the rotors of the aircraft according to any one of claims 1 to 8.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810106901.7A CN108248851B (en) | 2018-02-02 | 2018-02-02 | Device for protecting the rotor of an aircraft and aircraft with such a device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810106901.7A CN108248851B (en) | 2018-02-02 | 2018-02-02 | Device for protecting the rotor of an aircraft and aircraft with such a device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108248851A CN108248851A (en) | 2018-07-06 |
| CN108248851B true CN108248851B (en) | 2020-02-07 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810106901.7A Active CN108248851B (en) | 2018-02-02 | 2018-02-02 | Device for protecting the rotor of an aircraft and aircraft with such a device |
Country Status (1)
| Country | Link |
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| CN (1) | CN108248851B (en) |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8733690B2 (en) * | 2009-08-24 | 2014-05-27 | Joby Aviation, Inc. | Lightweight vertical take-off and landing aircraft and flight control paradigm using thrust differentials |
| WO2015000028A1 (en) * | 2013-07-01 | 2015-01-08 | Entecho Pty Ltd | An aerodynamic lifting device |
| CN204279926U (en) * | 2014-10-23 | 2015-04-22 | 深圳九星智能航空科技有限公司 | A kind of Brattice type multi-rotor aerocraft alighting gear with guide functions |
| CN104590555A (en) * | 2015-01-28 | 2015-05-06 | 王文有 | Electrodynamic multi-rotor helicopter |
| CN204846369U (en) * | 2015-06-19 | 2015-12-09 | 谭国荣 | Rotor unmanned aerial vehicle's rotor safety cover and rotor unmanned aerial vehicle |
| CN105799927A (en) * | 2016-03-17 | 2016-07-27 | 高大勇 | Ducted ring fixed wing helicopter |
| CN106945826B (en) * | 2017-02-16 | 2020-04-10 | 张爱伦 | Aircraft |
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2018
- 2018-02-02 CN CN201810106901.7A patent/CN108248851B/en active Active
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| CN108248851A (en) | 2018-07-06 |
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