CN212172532U - Novel slender flexible flapping wing and four-bar mechanism - Google Patents
Novel slender flexible flapping wing and four-bar mechanism Download PDFInfo
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- CN212172532U CN212172532U CN201921987807.3U CN201921987807U CN212172532U CN 212172532 U CN212172532 U CN 212172532U CN 201921987807 U CN201921987807 U CN 201921987807U CN 212172532 U CN212172532 U CN 212172532U
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- flapping wing
- bar linkage
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Abstract
The utility model provides a novel flexible flapping wing of elongated type and four-bar linkage, the one end of flexible flapping wing is the stiff end, and the other end is the free end, the stiff end is connected with the aircraft, and the junction is located flapping wing leading edge and flapping wing chord to the optional position between the mid point, and the flapping wing is including the exhibition to roof beam, chord to roof beam, covering, and the exhibition passes through rigid joint or flexible joint to roof beam and chord to roof beam and is connected, forms the skeleton, and the covering surrounds outside the skeleton and with adhesive or fix with rivet on the skeleton, and flexible joint includes four-bar linkage and restriction member, and the restriction member is located the exhibition to the roof beam, and four-bar linkage is located the chord to the roof beam.
Description
Technical Field
The utility model mainly relates to a flapping wing aircraft field especially relates to a novel flexible flapping wing of slim type.
Background
The flapping wing air vehicle has high aerodynamic efficiency and good maneuvering performance, and can provide lift force and thrust force simultaneously through the movement of the flapping wings. The traditional flapping wing air vehicle mostly adopts rigid wings, and has limited functions due to insufficient flexibility and unchanged shape; the developing intelligent actively-controlled deformable flapping wing relates to complex technologies such as intelligent materials and control, and is high in implementation difficulty.
SUMMERY OF THE UTILITY MODEL
The utility model provides a novel flexible flapping wing of elongated type, the one end of flexible flapping wing is the stiff end, and the other end is the free end, the stiff end is connected with the aircraft, and the junction is located flapping wing leading edge and flapping wing chord to the optional position between the mid point, and the flapping wing is including exhibition to roof beam, chord to roof beam, covering, and the exhibition passes through rigid joint and/or flexible joint to roof beam and chord to roof beam and is connected, forms the skeleton, and the covering surrounds outside the skeleton and on the skeleton with adhesive or fix with rivet in the skeleton, flexible joint is hinged joint, flexible joint still includes four-bar linkage and restriction member, and four-bar linkage is located chord to the roof beam, and the restriction member is located the exhibition to the roof beam.
The drive signal can be transmitted from the aircraft to the flapping wing through the connection to control the flapping of the flapping wing.
In some preferred embodiments, the aspect ratio of the elongated airfoil is 3 or greater.
In some preferred embodiments, the number of spanwise beams is odd and is equal to or greater than 3, preferably 5.
The spanwise beams serve as main supporting structures, and the number of the spanwise beams can be specifically listed as follows: 3. 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 31, 33, 35, 37, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, 59, 61, 63, 65, 67, 69, 71, 73, 75, 77, 79, 81, 83, 85, 87, 89, 91, 93, 95, 97, 99.
In some preferred embodiments, the spanwise beams are parallel to each other and the chordwise beams are parallel to each other.
In some preferred embodiments, the spanwise and chordwise beams at the leading edge are rigidly articulated and the spanwise and chordwise beams at the trailing edge are rigidly articulated.
The flexible joint can enable the chordwise beam and the spanwise beam to rotate relatively, and the rotation amplitude is limited by the limiting rod piece.
In some preferred embodiments, the rigid joint is connected by one of a bolt-nut connection, a welding connection, a rivet connection, a socket connection, a snap connection, a flange connection and a threaded connection.
The manner of attachment of the rigid joint is not limited to the above attachment forms.
In some preferred embodiments, the four-bar linkage includes a first bar, a second bar, a third bar, a fourth bar, a first hinge, a second hinge, a third hinge, and a fourth hinge, the first bar is connected to the second bar through the first hinge, the second bar is connected to the third bar through the second hinge, the third bar is connected to the fourth bar through the third hinge, and the fourth bar is connected to the first bar through the fourth hinge.
In some preferred embodiments, the four-bar linkage is fixed to the chordwise beam by a first hinge and a fourth hinge, and the first link is connected to the chordwise beam by the first hinge and the fourth hinge.
The second aspect of the utility model provides a four-bar linkage that is used for foretell flexible flapping wing of novel slim type, four-bar linkage includes connecting rod one, connecting rod two, connecting rod three, connecting rod four, hinge one, hinge two, hinge three, hinge four, and connecting rod one and connecting rod two pass through hinge one and connect, and connecting rod two and connecting rod three pass through hinge two and connect, and connecting rod three and connecting rod four pass through hinge three and connect, and connecting rod four and connecting rod one pass through hinge four and connect.
The working principle and the beneficial effects are as follows: the flexible joint comprises a four-bar mechanism and a limiting rod piece, and the amplitude of relative rotation between the spanwise beam and the chordwise beam is adjusted by adjusting the four-bar mechanism, so that adjustment of different 'flexibility' is realized. The flexible flapping wings can be flexibly adjusted to an optimal structure under the condition of facing different working condition loads by setting the distribution of the flexible joints and adjusting the flexibility of the flexible joints so as to meet the dual requirements of pneumatic performance and structural performance.
As shown in fig. 4, the four-bar linkage includes a first bar, a second bar, a third bar, a fourth bar, a first hinge, a second hinge, a third hinge, and a fourth hinge, the first bar is connected to the second bar through the first hinge, the second bar is connected to the third bar through the second hinge, the third bar is connected to the fourth bar through the third hinge, and the fourth bar is connected to the first bar through the fourth hinge. The first hinge and the fourth hinge are fixed on the chordwise beam, and the second hinge and the third hinge are adjusted according to requirements.
The rotation of the chordwise beam to the two sides of the spanwise beam can be limited by different amplitudes by adjusting the positions of the second hinge and the third hinge.
FIG. 4 is a general case of a four bar linkage, stopping when the chordwise beam rotates toward the upper side of the longitudinal beam, the second hinge contacts the restraining bar; when the chord-wise beam rotates to the lower side of the longitudinal beam, the hinge three is stopped when contacting the limiting rod piece.
Fig. 5 and 6 show two special cases.
As shown in FIG. 5, when the second connecting rod is parallel to the limiting rod and is located on the upper side of the first connecting rod, the rotation of the chordwise beam towards the upper side of the spanwise beam is completely limited.
As shown in fig. 6, when the second link is parallel to the limiting member and is located on the lower side of the first link, the rotation of the chordwise beam toward the lower side of the spanwise beam is completely limited.
Therefore, the limitation of the single-side rotation amplitude of the chordwise beam to the spanwise beam can be realized by replacing connecting rods with different lengths and adjusting the position of the hinge. The limitation of the rotation amplitude of the chordwise beam to the two sides of the spanwise beam can be realized by replacing connecting rods with different lengths and adjusting the position of the hinge, and the effect that the two sides have the same or different rotation amplitudes is achieved.
The utility model provides a novel slender type flexible flapping wing, which is a wing structure capable of being passively deformed. The flapping wing has the advantages that the problem of contradiction between the bearing capacity and deformation of the existing flapping wing is solved, the structure is simple, and the operation is easy. The inventor discovers that the flexible flapping wing provided by the utility model has the spanwise beam as the main supporting structure on the whole structure, and has enough bearing capacity and bending rigidity; due to the presence of flexible joints and rigid joints, it is possible to achieve a rigid-flexible balance of the structure, while in turn providing the necessary passive deformation without excessive compliance to satisfy the aerodynamic performance.
In addition, the inventor unexpectedly discovers that the chord-direction beam and the span-direction beam of the flexible flapping wing can have the effect of being rotatable in a certain range at the connecting part by arranging the four-bar linkage and the limiting rod piece at the flexible joint, and the flexibility of the flexible joint at different positions can be conveniently adjusted according to different conditions. Therefore, the flapping wings are deformed through large rotation and small deformation, and the pneumatic efficiency and the structural efficiency are improved.
Drawings
Fig. 1 is a schematic view of a novel elongated flexible flapping wing provided in some embodiments of the present invention;
fig. 2 is a schematic view of a novel elongated flexible flapping wing provided in some embodiments of the present invention;
fig. 3 is a schematic view of a flexible joint provided in some embodiments of the present invention;
fig. 4 is a schematic view of a four-bar linkage mechanism provided in some embodiments of the present invention;
fig. 5 is a schematic view of a four bar linkage mechanism provided in some embodiments of the present invention;
fig. 6 is a schematic view of a four bar linkage mechanism provided in some embodiments of the present invention;
the drawing is marked as follows, 1 is a fixed end, 2 is a spanwise beam, 3 is a chordwise beam, 4 is a skin, 5 is a flexible joint, 6 is a rigid joint, 7 is a four-bar mechanism, 8 is a hinge, 9 is a limiting rod, 10 is a first connecting bar, 11 is a second connecting bar, 12 is a third connecting bar, 13 is a fourth connecting bar, 14 is a first hinge, 15 is a second hinge, 16 is a third hinge, and 17 is a fourth hinge.
Detailed Description
The utility model discloses in, slim type wing section is the wing section of aspect ratio more than or equal to 3.
Example 1
As shown in fig. 1, a novel slender flexible flapping wing, the one end of flexible flapping wing is stiff end 1, and the other end is the free end, the stiff end is connected with the aircraft, and the junction is located flapping wing leading edge and flapping wing chord to the optional position between the midpoint, and the flapping wing is including exhibition to roof beam 2, chordwise roof beam 3, covering 4, and the exhibition is connected through rigid joint 6 and flexible joint 5 to roof beam and chordwise roof beam, forms the skeleton, and the covering surrounds outside the skeleton and is fixed in on the skeleton with the adhesive, and flexible joint is the hinged joint 8 connection, flexible joint still includes four-bar linkage 7 and restriction member 9, and four-bar linkage is located chordwise roof beam, and the restriction member is located exhibition and is to the roof beam.
The number of spanwise beams is 3. The first spanwise beam is the leading edge of the flapping wing, and the third spanwise beam is the trailing edge of the flapping wing.
The spanwise beams are parallel to each other, and the chordwise beams are parallel to each other.
The spanwise beam and the chordwise beam which are positioned at the front edge are connected through a rigid joint, and the spanwise beam and the chordwise beam which are positioned at the rear edge are connected through a rigid joint. The second spanwise beam is connected with the chordwise beam through a flexible joint.
The rigid joint is connected in a bolt and nut mode.
As shown in fig. 4, the four-bar linkage includes a first bar 10, a second bar 11, a third bar 12, a fourth bar 13, a first hinge 14, a second hinge 15, a third hinge 16, and a fourth hinge 17, the first bar is connected to the second bar through the first hinge, the second bar is connected to the third bar through the second hinge, the third bar is connected to the fourth bar through the third hinge, and the fourth bar is connected to the first bar through the fourth hinge.
The four-bar mechanism is fixed on the chordwise beam through a first hinge and a fourth hinge, and the first connecting bar is rotatably connected to the chordwise beam through the first hinge and the fourth hinge.
The position of the four-bar linkage at the flexible joint is shown in figure 4, the second connecting bar and the fourth connecting bar are respectively positioned at two sides of the first connecting bar, and the rotation amplitude of the chordwise beam to two sides of the spanwise beam is limited, so that the chordwise beam and the spanwise beam of the flexible flapping wing have a bidirectional rotatable effect at the joint, and the rotation amplitude can be adjusted.
Example 2
As shown in fig. 1, a novel slender flexible flapping wing, the one end of flexible flapping wing is stiff end 1, and the other end is the free end, the stiff end is connected with the aircraft, and the junction is located flapping wing leading edge and flapping wing chord to the optional position between the midpoint, and the flapping wing is including exhibition to roof beam 2, chord to roof beam 3, covering 4, and the exhibition is connected through rigid joint 6 and flexible joint 5 to roof beam and chord to roof beam, forms the skeleton, and the covering surrounds outside the skeleton and with fix with rivet on the skeleton, and flexible joint is the hinge 8 connection, flexible joint still includes four-bar linkage 7 and restriction member 9, and four-bar linkage is located chord to the roof beam, and the restriction member is located exhibition to the roof beam.
The number of spanwise beams is 3. The first spanwise beam is the leading edge of the flapping wing, and the third spanwise beam is the trailing edge of the flapping wing.
The spanwise beams are parallel to each other, and the chordwise beams are parallel to each other.
The spanwise beam and the chordwise beam which are positioned at the front edge are connected through a rigid joint, and the spanwise beam and the chordwise beam which are positioned at the rear edge are connected through a rigid joint. The second spanwise beam is connected with the chordwise beam through a flexible joint.
The rigid joint is connected in a bolt and nut mode.
As shown in fig. 4, the four-bar linkage includes a first bar 10, a second bar 11, a third bar 12, a fourth bar 13, a first hinge 14, a second hinge 15, a third hinge 16, and a fourth hinge 17, the first bar is connected to the second bar through the first hinge, the second bar is connected to the third bar through the second hinge, the third bar is connected to the fourth bar through the third hinge, and the fourth bar is connected to the first bar through the fourth hinge.
The four-bar mechanism is fixed on the chordwise beam through a first hinge and a fourth hinge, and the first connecting bar is rotatably connected to the chordwise beam through the first hinge and the fourth hinge.
The position of the four-bar linkage at the flexible joint is shown in figure 5, the second connecting bar is parallel to the limiting rod piece and is positioned on the upper side of the first connecting bar, and the second connecting bar completely limits the rotation of the chordwise beam to the upper side of the spanwise beam, so that the chordwise beam and the spanwise beam of the flexible flapping wing have a unidirectional rotatable effect at the joint, and the rotation amplitude can be adjusted
Example 3
As shown in fig. 2, a novel slender flexible flapping wing, the one end of flexible flapping wing is stiff end 1, and the other end is the free end, the stiff end is connected with the aircraft, and the junction is located flapping wing leading edge and flapping wing chord to the optional position between the midpoint, and the flapping wing is including exhibition to roof beam 2, chordwise roof beam 3, covering 4, and the exhibition is connected through rigid joint 6 and flexible joint 5 to roof beam and chordwise roof beam, forms the skeleton, and the covering surrounds outside the skeleton and is fixed in on the skeleton with the adhesive, and flexible joint is the hinged joint 8 connection, flexible joint still includes four-bar linkage 7 and restriction member 9, and four-bar linkage is located chordwise roof beam, and the restriction member is located exhibition and is to the roof beam.
The number of spanwise beams is 5. The first spanwise beam is the leading edge of the flapping wing, and the fifth spanwise beam is the trailing edge of the flapping wing.
The spanwise beams are parallel to each other, and the chordwise beams are parallel to each other.
The spanwise beam and the chordwise beam which are positioned at the front edge are connected through a rigid joint, and the spanwise beam and the chordwise beam which are positioned at the rear edge are connected through a rigid joint. The second spanwise beam is connected with the chordwise beam through a flexible joint.
The rigid joint is connected by rivets.
As shown in fig. 4, the four-bar linkage includes a first bar 10, a second bar 11, a third bar 12, a fourth bar 13, a first hinge 14, a second hinge 15, a third hinge 16, and a fourth hinge 17, the first bar is connected to the second bar through the first hinge, the second bar is connected to the third bar through the second hinge, the third bar is connected to the fourth bar through the third hinge, and the fourth bar is connected to the first bar through the fourth hinge.
The four-bar mechanism is fixed on the chordwise beam through a first hinge and a fourth hinge, and the first connecting bar is rotatably connected to the chordwise beam through the first hinge and the fourth hinge.
The position of the four-bar linkage at the flexible joint is shown in figure 5, the second connecting bar is parallel to the limiting rod piece and is positioned on the upper side of the first connecting bar, and the rotation of the chordwise beam to the upper side of the spanwise beam is completely limited, so that the chordwise beam and the spanwise beam of the flexible flapping wing have a unidirectional rotatable effect at the joint, and the rotation amplitude can be adjusted.
Example 4
As shown in fig. 2, a novel slender flexible flapping wing, the one end of flexible flapping wing is stiff end 1, and the other end is the free end, the stiff end is connected with the aircraft, and the junction is located flapping wing leading edge and flapping wing chord to the optional position between the midpoint, and the flapping wing is including exhibition to roof beam 2, chord to roof beam 3, covering 4, and the exhibition is connected through rigid joint 6 and flexible joint 5 to roof beam and chord to roof beam, forms the skeleton, and the covering surrounds outside the skeleton and with fix with rivet on the skeleton, and flexible joint is the hinge 8 connection, flexible joint still includes four-bar linkage 7 and restriction member 9, and four-bar linkage is located chord to the roof beam, and the restriction member is located exhibition to the roof beam.
The number of spanwise beams is 5. The first spanwise beam is the leading edge of the flapping wing, and the fifth spanwise beam is the trailing edge of the flapping wing.
The spanwise beams are parallel to each other, and the chordwise beams are parallel to each other.
The spanwise beam and the chordwise beam which are positioned at the front edge are connected through a rigid joint, and the spanwise beam and the chordwise beam which are positioned at the rear edge are connected through a rigid joint. The second spanwise beam is connected with the chordwise beam through a flexible joint.
The rigid joint is connected by rivets.
As shown in fig. 4, the four-bar linkage includes a first bar 10, a second bar 11, a third bar 12, a fourth bar 13, a first hinge 14, a second hinge 15, a third hinge 16, and a fourth hinge 17, the first bar is connected to the second bar through the first hinge, the second bar is connected to the third bar through the second hinge, the third bar is connected to the fourth bar through the third hinge, and the fourth bar is connected to the first bar through the fourth hinge.
The four-bar mechanism is fixed on the chordwise beam through a first hinge and a fourth hinge, and the first connecting bar is rotatably connected to the chordwise beam through the first hinge and the fourth hinge.
The position of the four-bar linkage at the flexible joint is shown in figure 6, the second connecting bar is parallel to the limiting rod piece and is positioned on one side of the connecting bar, and the rotation of the chordwise beam to the upper side of the spanwise beam is completely limited, so that the chordwise beam and the spanwise beam of the flexible flapping wing have a unidirectional rotatable effect at the joint, and the rotation amplitude can be adjusted.
Claims (11)
1. The utility model provides a novel flexible flapping wing of elongated type, its characterized in that, the one end of flexible flapping wing is the stiff end, and the other end is the free end, the stiff end is connected with the aircraft, and the junction is located flapping wing leading edge and flapping wing chord to the optional position between the mid point, and the flapping wing is including exhibition to roof beam, chord to roof beam, covering, and the exhibition passes through rigid joint and/or flexible joint to roof beam and chord to the roof beam and is connected, forms the skeleton, and the covering surrounds outside the skeleton and with adhesive or fix with rivet on the skeleton, and flexible joint is hinged joint, flexible joint still includes four-bar linkage and restriction member, and the restriction member is located the exhibition to the roof beam, and four-bar linkage is located chord to the roof beam.
2. The novel elongated flexible flapping wing of claim 1 wherein said elongated airfoil shape has an aspect ratio of 3 or greater.
3. The novel elongated flexible flapping wing of claim 1 wherein said spanwise beams are odd in number and equal to or greater than 3.
4. The novel elongated flexible flapping wing of claim 1 wherein said spanwise beams are odd in number and equal to or greater than 5.
5. The novel elongated flexible flapping wing of claim 1 wherein the span-wise beams are parallel to each other.
6. The novel elongated flexible flapping wing of claim 1 wherein the chordwise beams are parallel to each other.
7. The novel elongated flexible flapping wing of claim 1 wherein the span-wise and chord-wise spars at the leading edge are rigidly articulated and the span-wise and chord-wise spars at the trailing edge are rigidly articulated.
8. The novel elongated flexible flapping wing of claim 1 wherein said rigid joints are connected by one of a bolt and nut connection, a weld, a rivet connection, a socket connection, a snap connection, a flange connection, and a threaded connection.
9. The novel elongated flexible flapping wing of claim 1 wherein said four bar linkage comprises first bar linkage, second bar linkage, third bar linkage, fourth bar linkage, first hinge, second hinge, third hinge, and fourth hinge, wherein first bar linkage and second bar linkage are connected by first hinge, second bar linkage and third bar linkage are connected by second hinge, third bar linkage and fourth bar linkage are connected by third hinge, and fourth bar linkage and first bar linkage are connected by fourth hinge.
10. The novel elongated flexible flapping wing of claim 9 wherein said four bar linkage is attached to the chord wise beam by a first hinge and a fourth hinge, and wherein the first link is attached to the chord wise beam by a first hinge and a fourth hinge.
11. A four-bar linkage mechanism for a new elongated flexible flapping wing according to any one of claims 1 to 10, wherein the four-bar linkage mechanism comprises a first bar, a second bar, a third bar, a fourth bar, a first hinge, a second hinge, a third hinge and a fourth hinge, the first bar is connected with the second bar through the first hinge, the second bar is connected with the third bar through the second hinge, the third bar is connected with the fourth bar through the third hinge, and the fourth bar is connected with the first bar through the fourth hinge.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921987807.3U CN212172532U (en) | 2019-11-18 | 2019-11-18 | Novel slender flexible flapping wing and four-bar mechanism |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921987807.3U CN212172532U (en) | 2019-11-18 | 2019-11-18 | Novel slender flexible flapping wing and four-bar mechanism |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN212172532U true CN212172532U (en) | 2020-12-18 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201921987807.3U Expired - Fee Related CN212172532U (en) | 2019-11-18 | 2019-11-18 | Novel slender flexible flapping wing and four-bar mechanism |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN212172532U (en) |
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2019
- 2019-11-18 CN CN201921987807.3U patent/CN212172532U/en not_active Expired - Fee Related
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| GR01 | Patent grant | ||
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Granted publication date: 20201218 Termination date: 20211118 |