CN109896009A - Propeller and unmanned plane - Google Patents
Propeller and unmanned plane Download PDFInfo
- Publication number
- CN109896009A CN109896009A CN201910126236.2A CN201910126236A CN109896009A CN 109896009 A CN109896009 A CN 109896009A CN 201910126236 A CN201910126236 A CN 201910126236A CN 109896009 A CN109896009 A CN 109896009A
- Authority
- CN
- China
- Prior art keywords
- blade
- connecting pin
- connection end
- changeover portion
- blade root
- 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.)
- Granted
Links
- 230000010355 oscillation Effects 0.000 abstract description 3
- 230000009286 beneficial effect Effects 0.000 abstract description 2
- 230000001788 irregular Effects 0.000 abstract description 2
- 238000013461 design Methods 0.000 description 6
- 230000007704 transition Effects 0.000 description 6
- 238000010586 diagram Methods 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 230000002411 adverse Effects 0.000 description 1
- 235000013399 edible fruits Nutrition 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 230000001052 transient effect Effects 0.000 description 1
Landscapes
- Structures Of Non-Positive Displacement Pumps (AREA)
- Wind Motors (AREA)
Abstract
The invention discloses a kind of propellers, including blade root, blade and changeover portion, the changeover portion includes the first connecting pin, first connecting pin is connect with the blade root, the changeover portion includes the second connection end that section is aerofoil profile or part aerofoil profile, the second connection end is connect with the blade, is spline surface between first connecting pin and the second connection end, so that the blade root is transitioned into the blade the changeover portion in a manner of continual curvature.Beneficial effects of the present invention: propeller and unmanned plane of the present invention, changeover portion is set between blade and blade root, the irregular pneumatic face of blade is allowed smoothly to be transformed into the shape of blade root through changeover portion, to mitigate air-flow the phenomenon that blade back separates, the thrust of propeller is improved.In addition, changeover portion can also increase the intensity of blade, reduce Oscillation Amplitude when propeller operation.
Description
Technical field
The present invention relates to air vehicle technique fields, it particularly relates to a kind of propeller and unmanned plane.
Background technique
Currently, in the design of multi-rotor unmanned aerial vehicle, when the pneumatic efficiency superiority and inferiority of propeller determines the hovering of unmanned plane
Between and voyage.In the design of existing multi-rotor unmanned aerial vehicle, the design of propeller leads to gas there are blade root, blade transition are improper
The low problem of efficiency of movement.That is, usually blade aerodynamic face and propeller hub are directly connected to, and in junction rounded corner, because of blade ruler
The radius of very little limitation, rounded corner cannot be too big, very big so as to cause surface curvature, causes stress excessively high, easily causes material tired
Labor influences service life.
For the problems in the relevant technologies, currently no effective solution has been proposed.
Summary of the invention
For above-mentioned technical problem in the related technology, the present invention proposes a kind of propeller and unmanned plane, can will not advise
Pneumatic face then is smoothly transformed into the section of blade root, improves pneumatic efficiency.
To realize the above-mentioned technical purpose, the technical scheme of the present invention is realized as follows:
A kind of propeller, including blade root, blade and changeover portion, the changeover portion include the first connecting pin, and described first connects
It connects end to connect with the blade root, the changeover portion includes the second connection end that section is aerofoil profile or part aerofoil profile, and described second connects
It connects end to connect with the blade, is spline surface between first connecting pin and the second connection end, so that the blade root
The blade is transitioned into a manner of continual curvature the changeover portion.
Preferably, the section of first connecting pin is round rectangle.
Preferably, the spline surface is by several curve shapes for connecting first connecting pins and the second connection end
Guide wire.
Preferably, when the section of the second connection end is the part aerofoil profile of rear missing, the guide line includes: first
Guide line is Bezier, connect the first connecting pin the first fillet and second connection end leading edge, and with blade root and paddle
The leading edge of leaf is tangent；Third guide line is Bezier, connects the third fillet and second connection end of the first connecting pin
Upper vertex, and it is tangent with blade root rear surface and blade rear surface coboundary；4th guide line is Bezier, connection the
The third fillet of one connecting pin and the lower vertex of second connection end, and it is tangent with blade root rear surface and blade rear surface lower boundary.
Preferably, the guide line further include: the second guide line is Bezier, the of the first connecting pin of connection
The highest point of two fillets and second connection end, and it is tangent with the upper surface of blade root and blade；5th guide line is that Bezier is bent
Line, connect the first connecting pin the 4th fillet and second connection end lower edge rear 1/5 chord length at, and with the blade root lower surface
It is tangent with blade lower surface.
Preferably, the blade has the batten song established using multiple cross sectional shapes as the control plane of aerofoil profile or part aerofoil profile
The shape in face.
Preferably, the chord length range of the blade tip of the blade is the 1/5~1/9 of blade the widest part chord length.
Preferably, the blade root is equipped with mounting hole, and the mounting hole that will be close to blade is fixed to the vertical range of blade outer end
Justice is R,
The control plane is located at 0.3R, 0.4R, 0.5R, 0.6,0.7R, 0.8R, 0.9R apart from the mounting hole
Place.
Preferably, the torsion angular region of the blade tip of the blade is between 8 °~11.5 °.
Another aspect of the present invention is related to a kind of unmanned plane, including above-mentioned propeller or its improvement project.
Beneficial effects of the present invention: transition is arranged in propeller and unmanned plane of the present invention between blade and blade root
Section, allows the irregular pneumatic face of blade to be smoothly transformed into the shape of blade root through changeover portion, to mitigate air-flow in paddle
The phenomenon that leaf upper surface separates, improves the thrust of propeller.In addition, changeover portion can also increase the intensity of blade, reduce spiral
Oscillation Amplitude when paddle is run.
Detailed description of the invention
It in order to more clearly explain the embodiment of the invention or the technical proposal in the existing technology, below will be to institute in embodiment
Attached drawing to be used is needed to be briefly described, it should be apparent that, the accompanying drawings in the following description is only some implementations of the invention
Example, for those of ordinary skill in the art, without creative efforts, can also obtain according to these attached drawings
Obtain other attached drawings.
Fig. 1 is the structural schematic diagram of propeller of the present invention；
Fig. 2 is the structural schematic diagram of changeover portion of the present invention；
Fig. 3 is the figure for illustrating the parameter of propeller of the present invention.
In figure: 1. propellers；10. blade root；20. blade；30. changeover portion；31. the first connecting pin；32. second connection end.
Specific embodiment
Following will be combined with the drawings in the embodiments of the present invention, and technical solution in the embodiment of the present invention carries out clear, complete
Site preparation description, it is clear that described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.It is based on
Embodiment in the present invention, those of ordinary skill in the art's every other embodiment obtained belong to what the present invention protected
Range.
Fig. 1 is the structural schematic diagram of propeller of the present invention.
Fig. 2 is the structural schematic diagram of changeover portion of the present invention.
As shown in Fig. 1~2, the propeller 1, including blade root 10, blade 20 and changeover portion according to embodiments of the present invention
30, changeover portion 30 includes the first connecting pin 31, and the first connecting pin 31 connect with blade root 10, changeover portion 30 including section for aerofoil profile or
The second connection end 32 of part aerofoil profile, second connection end 32 are connect with blade 20, the first connecting pin 31 and second connection end 32 it
Between be spline surface so that blade root 10 is transitioned into blade 20 the changeover portion 30 in a manner of continual curvature.
Blade root 10 is identical with the section of one end that changeover portion 30 connects and the size and shape of the first connecting pin 31, from
And realize the seamless and smooth transition between blade root 10 and changeover portion 30.The section of one end that blade 20 is connect with changeover portion 30
It is identical with the size and shape of second connection end 32, to realize seamless between blade 20 and changeover portion 30 and smooth
Transition.The section of second connection end 32 is aerofoil profile or part aerofoil profile, and part aerofoil profile refers to be formed after aerofoil profile removes certain a part
Shape, such as aftermentioned rear missing part aerofoil profile, as rear is clipped on the basis of aerofoil profile, thus in the tail of aerofoil profile
Portion forms the shape on vertex and lower vertex.Between first connecting pin 31 and second connection end 32 (i.e. the circumferential surface of changeover portion 30)
For spline surface, blade root 10 excessively arrives blade 20 through changeover portion 30 in a manner of continual curvature as a result, does not generate any deep camber
Curve, can reduce air-flow blade back separation the phenomenon that, improve 2%~4% thrust, while changeover portion design energy
Enough increase blade intensity, Oscillation Amplitude when propeller is run reduces 30%~50%, and it is improper to solve blade blade root transition
The problem of.
It is directly connected in addition, the presence of changeover portion avoids blade aerodynamic face with propeller hub, propeller is from propeller shank to paddle
The curvature very little of root is not in sharp corner angle and rough situation, to reduce under changeover portion especially changeover portion
The stress (according to finite element analysis, such transient mode can at least reduce by 50% surface stress) on surface, it is not easy to make
At fatigue of materials, help to prolong the service life.
The section of first connecting pin 31 is preferably round rectangle, correspondingly, section and the blade root 10 of the first connecting pin 31
Section is identical, that is, the section of blade root 10 is also round rectangle, and fillet can mitigate stress the case where edges and corners are concentrated, simultaneously
It is not easy to scratch manpower.
Preferably, spline surface by it is several connection the first connecting pin 31 and second connection end 32 curve shapes guide line
Definition.With the help of guide line, the section of propeller 1 is transformed into the aerofoil profile of blade 20 from the round rectangle of blade root 10, and
The curve of any deep camber is not generated.
Specifically, four fillets of the first connecting pin 31 of round rectangle are marked as follows: table on changeover portion 30
Sidelights in front are the first fillet A, and the second fillet B is denoted as on rear side of 30 upper surface of changeover portion, and the is denoted as on rear side of 30 lower surface of changeover portion
Three fillet C, 30 lower surface of changeover portion front side are denoted as the 4th fillet D.Wherein, the section of second connection end 32 is the portion of rear missing
When point aerofoil profile, it is Bezier that guide line, which includes: the first guide line L1, connect the first connecting pin 31 the first fillet A and
The leading edge O of second connection end 32, and it is tangent with the leading edge of blade root 10 and blade 20；Third guide line L3, is Bezier,
Connect the third fillet C of the first connecting pin 31 and the upper vertex P of second connection end 32, and with after 10 rear surface of blade root and blade 20
Edge face coboundary is tangent；4th guide line L4 is Bezier, connects the third fillet C and second of the first connecting pin 31
The lower vertex Q of connecting pin 32, and it is tangent with 10 rear surface of blade root and 20 rear surface lower boundary of blade.Wherein, third guide line L3
Connection be third fillet C upper end, the 4th guide line L4 connection be third fillet C lower end, L3, L4, third fillet C, P
The rear surface of changeover portion 30 is formed with the line of Q.The face that blade 20 is connect with the rear surface of the changeover portion 30 is blade 20
Rear surface.
More reasonable smooth surface in order to obtain further increases pneumatic effect so that changeover portion 30 preferably plays a role
Fruit, guide line further include: the second guide line L2, is Bezier, connects the second fillet B and second of the first connecting pin 31
The highest point R of connecting pin 32, and it is tangent with the upper surface of blade root 10 and blade 20；5th guide line L5 is Bezier,
Connect S at rear 1/5 chord length of 32 lower edge of the 4th fillet D and second connection end of the first connecting pin 31, and with 10 following table of blade root
Face and 20 lower surface of blade are tangent.
More than, the changeover portion of propeller 1 of the present invention is illustrated, next, to the blade 20 of propeller 1
It is illustrated.
Fig. 3 is the figure for illustrating the parameter of propeller of the present invention.
In the prior art, blade is generally linear, paddle and the inventors discovered that, if blade 20 have with multiple sections
Shape is the shape of the spline surface of the control plane foundation of aerofoil profile or part aerofoil profile, then can effectively provide pneumatic efficiency.According to
Experiment test, such blade aerodynamic efficiency can be improved 5%~10% or so.
Blade root 10 is equipped with mounting hole, and mounting hole to the vertical range of 20 outer end T of blade that will be close to blade 20 is defined as
R, control plane are located at 0.3R, 0.4R, 0.5R, 0.6R, 0.7R, 0.8R, 0.9R of mounting hole.
In addition, the chord length of 20 the widest part of blade is defined as C, torsion angle is defined as paddle as specific embodiment
The aerofoil profile in 20 section of leaf shows the angle with 10 upper surface of blade root, and the design parameter of blade is as shown in table 1.
1. blade design parameter of table
In addition, inventors have found that the chord length of the blade tip (i.e. the position of 1.0R) of blade 20 ranges preferably from blade the widest part
The 1/5~1/9 of chord length.The torsion angular region of blade tip is preferably between 8 °~11.5 °.
By the above-mentioned improvement to blade form, the research of angular region is reversed to blade tip chord length range and blade tip, it can not only
Blade aerodynamic efficiency is enough set to can be improved 5%~10% or so, it is also possible that the rotary inertia of propeller 1 is become by 1000g*mm
For 760g*mm or so, rotary inertia is effectively reduced, avoids responding motor control and causes adverse effect.
Another aspect of the present invention is related to a kind of unmanned plane, including above-mentioned propeller or its optimal technical scheme.This
The propeller blade of the unmanned plane of sample and the reasonable transition of blade root, pneumatic efficiency is high, and surface stress is low, helps to improve using the longevity
Life, in addition, propeller rotational inertia is small, motor response is rapid.
The foregoing is merely illustrative of the preferred embodiments of the present invention, is not intended to limit the invention, all in essence of the invention
Within mind and principle, any modification, equivalent replacement, improvement and so on be should all be included in the protection scope of the present invention.
Claims (10)
1. a kind of propeller, which is characterized in that
Including blade root, blade and changeover portion,
The changeover portion includes the first connecting pin, and first connecting pin is connect with the blade root,
The changeover portion includes the second connection end that section is aerofoil profile or part aerofoil profile, and the second connection end and the blade connect
It connects,
Between first connecting pin and the second connection end be spline surface so that the blade root by the changeover portion with
The mode of continual curvature is transitioned into the blade.
2. propeller according to claim 1, which is characterized in that
The section of first connecting pin is round rectangle.
3. propeller according to claim 2, which is characterized in that
The spline surface is determined by the guide line of several connections first connecting pin and the curve shape of the second connection end
Justice.
4. propeller according to claim 3, which is characterized in that
When the section of the second connection end is the part aerofoil profile of rear missing, the guide line includes:
First guide line is Bezier, the first fillet of the first connecting pin of connection and the leading edge of second connection end, and with
The leading edge of blade root and blade is tangent；
Third guide line is Bezier, connects the third fillet of the first connecting pin and the upper vertex of second connection end, and
It is tangent with blade root rear surface and blade rear surface coboundary；
4th guide line is Bezier, connects the third fillet of the first connecting pin and the lower vertex of second connection end, and
It is tangent with blade root rear surface and blade rear surface lower boundary.
5. propeller according to claim 4, which is characterized in that
The guide line further include:
Second guide line is Bezier, connects the second fillet of the first connecting pin and the highest point of second connection end, and
It is tangent with the upper surface of blade root and blade；
5th guide line is Bezier, after the 4th fillet and second connection end lower edge that connect the first connecting pin
At 1/5 chord length, and it is tangent with the blade root lower surface and blade lower surface.
6. propeller according to claim 1, which is characterized in that
The blade has the shape for the spline surface established using multiple cross sectional shapes as the control plane of aerofoil profile or part aerofoil profile.
7. propeller according to claim 6, which is characterized in that
The chord length range of the blade tip of the blade is the 1/5~1/9 of blade the widest part chord length.
8. propeller according to claim 6, which is characterized in that
The blade root is equipped with mounting hole, and mounting hole to the vertical range of blade outer end that will be close to blade is defined as R,
The control plane is located at 0.3R, 0.4R, 0.5R, 0.6R, 0.7R, 0.8R, 0.9R apart from the mounting hole.
9. propeller according to claim 6, which is characterized in that
The torsion angular region of the blade tip of the blade is between 8 °~11.5 °.
10. a kind of unmanned plane, which is characterized in that including propeller according to any one of claims 1 to 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910126236.2A CN109896009B (en) | 2019-02-20 | 2019-02-20 | Screw and unmanned aerial vehicle |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910126236.2A CN109896009B (en) | 2019-02-20 | 2019-02-20 | Screw and unmanned aerial vehicle |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109896009A true CN109896009A (en) | 2019-06-18 |
| CN109896009B CN109896009B (en) | 2024-06-21 |
Family
ID=66945063
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910126236.2A Active CN109896009B (en) | 2019-02-20 | 2019-02-20 | Screw and unmanned aerial vehicle |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109896009B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115384765A (en) * | 2022-10-31 | 2022-11-25 | 四川蓉远地测科技有限公司 | Rotor unmanned aerial vehicle driving device and assembling method thereof |
Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1070662A1 (en) * | 1999-07-20 | 2001-01-24 | Eurocopter Deutschland GmbH | Rotorblade for a bearingless helicopter rotor |
| KR20120037195A (en) * | 2010-10-11 | 2012-04-19 | 유로캅터 도이칠란트 게엠베하 | Rotor blade made of a fibre-reinforced composite material and production method for it |
| CN102582831A (en) * | 2010-12-02 | 2012-07-18 | 阿加斯塔西部有限公司 | Aerofoil |
| CN103587684A (en) * | 2013-10-24 | 2014-02-19 | 中国科学院长春光学精密机械与物理研究所 | Two-dimensional airfoil profile with low-Reynolds number and rotor wing with two-dimensional airfoil profile |
| CN203685493U (en) * | 2013-12-26 | 2014-07-02 | 中国科学院工程热物理研究所 | Big-thickness blunt trailing edge blade for wind turbine |
| CN106741858A (en) * | 2016-12-06 | 2017-05-31 | 顺丰科技有限公司 | Propeller fin |
| CN106894947A (en) * | 2017-03-06 | 2017-06-27 | 重庆大学 | A kind of low wind speed speed-changing oar-changing pneumatic equipment bladess Optimization Design |
| WO2017172000A2 (en) * | 2016-01-29 | 2017-10-05 | Sikorsky Aircraft Corporation | Helicopter tail rotor blades and blade assemblies |
| CN206691356U (en) * | 2017-02-28 | 2017-12-01 | 深圳市大疆创新科技有限公司 | Propeller, Power Component and aircraft |
| CN109110124A (en) * | 2018-09-03 | 2019-01-01 | 南京航空航天大学 | A kind of new Main Rotor Blade |
| CN109178295A (en) * | 2018-10-24 | 2019-01-11 | 深圳市飞米机器人科技有限公司 | Blade, propeller and aircraft |
| CN208412129U (en) * | 2018-05-29 | 2019-01-22 | 中山星图航空航天技术有限公司 | propeller |
| CN209921609U (en) * | 2019-02-20 | 2020-01-10 | 顺丰科技有限公司 | Screw and unmanned aerial vehicle |
-
2019
- 2019-02-20 CN CN201910126236.2A patent/CN109896009B/en active Active
Patent Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1070662A1 (en) * | 1999-07-20 | 2001-01-24 | Eurocopter Deutschland GmbH | Rotorblade for a bearingless helicopter rotor |
| KR20120037195A (en) * | 2010-10-11 | 2012-04-19 | 유로캅터 도이칠란트 게엠베하 | Rotor blade made of a fibre-reinforced composite material and production method for it |
| CN102582831A (en) * | 2010-12-02 | 2012-07-18 | 阿加斯塔西部有限公司 | Aerofoil |
| CN103587684A (en) * | 2013-10-24 | 2014-02-19 | 中国科学院长春光学精密机械与物理研究所 | Two-dimensional airfoil profile with low-Reynolds number and rotor wing with two-dimensional airfoil profile |
| CN203685493U (en) * | 2013-12-26 | 2014-07-02 | 中国科学院工程热物理研究所 | Big-thickness blunt trailing edge blade for wind turbine |
| WO2017172000A2 (en) * | 2016-01-29 | 2017-10-05 | Sikorsky Aircraft Corporation | Helicopter tail rotor blades and blade assemblies |
| CN106741858A (en) * | 2016-12-06 | 2017-05-31 | 顺丰科技有限公司 | Propeller fin |
| CN206691356U (en) * | 2017-02-28 | 2017-12-01 | 深圳市大疆创新科技有限公司 | Propeller, Power Component and aircraft |
| CN106894947A (en) * | 2017-03-06 | 2017-06-27 | 重庆大学 | A kind of low wind speed speed-changing oar-changing pneumatic equipment bladess Optimization Design |
| CN208412129U (en) * | 2018-05-29 | 2019-01-22 | 中山星图航空航天技术有限公司 | propeller |
| CN109110124A (en) * | 2018-09-03 | 2019-01-01 | 南京航空航天大学 | A kind of new Main Rotor Blade |
| CN109178295A (en) * | 2018-10-24 | 2019-01-11 | 深圳市飞米机器人科技有限公司 | Blade, propeller and aircraft |
| CN209921609U (en) * | 2019-02-20 | 2020-01-10 | 顺丰科技有限公司 | Screw and unmanned aerial vehicle |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115384765A (en) * | 2022-10-31 | 2022-11-25 | 四川蓉远地测科技有限公司 | Rotor unmanned aerial vehicle driving device and assembling method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109896009B (en) | 2024-06-21 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN205366054U (en) | Screw, power component and aircraft | |
| US10232934B2 (en) | Wing tip with optimum loading | |
| US9085359B2 (en) | Rotor blade tip planform | |
| CN207826548U (en) | A kind of high-efficient low-noise rotor | |
| JPH1199994A (en) | Blade with sweep-back wing end for rotor of aircraft | |
| US20120288374A1 (en) | Air propeller arrangement and aircraft | |
| WO2008091299A3 (en) | High performance outboard section for rotor blades | |
| CN105923155A (en) | Low-noise paddle for rotor craft | |
| KR102386093B1 (en) | Thick airfoil shapes for blade necks and for blade cuff fairings for an aircraft rotor | |
| CN101501302A (en) | Rotor blade for a high speed rotary-wing aircraft | |
| CN106892104A (en) | The rotator blade of its construction performance improvement suitable for the acoustics improvement during flight of marching into the arena and in flight forward | |
| CN203666968U (en) | Negative dihedral aerofoil winglet structure | |
| CN203740120U (en) | Aerodynamic structure of morphing aircraft with wide flight envelope | |
| CN107512382A (en) | One kind combination aircraft | |
| CN104816827A (en) | Low-induced-resistance helicopter rotor wing with sweepback anhedral wingtip | |
| CN109896009A (en) | Propeller and unmanned plane | |
| CN203558201U (en) | Airplane wing | |
| US20190248472A1 (en) | Propeller assembly | |
| CN106564588B (en) | Unmanned helicopter blade and unmanned helicopter | |
| CN109533314A (en) | A kind of light-duty unmanned helicopter Rotor Aerodynamics Shape | |
| CN209921609U (en) | Screw and unmanned aerial vehicle | |
| CN210793629U (en) | Helicopter rotor blade tip structure and rotor | |
| RU2603710C1 (en) | Rotary-winged aircraft propeller blade | |
| US5911559A (en) | Airfoiled blade for a propeller | |
| CN109573016A (en) | A kind of light-duty unmanned helicopter tail-rotor aerodynamic configuration |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| TA01 | Transfer of patent application right |
Effective date of registration: 20210714 Address after: 518000 5th floor, block B, building 1, software industry base, Yuehai street, Nanshan District, Shenzhen City, Guangdong Province Applicant after: Fengyi Technology (Shenzhen) Co.,Ltd. Address before: 518000 Xuefu Road (south) and Baishi Road (east) intersection of Nanshan District, Shenzhen City, Guangdong Province, 6-13 floors, Block B, Shenzhen Software Industry Base Applicant before: SF TECHNOLOGY Co.,Ltd. |
|
| TA01 | Transfer of patent application right | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |