CN108839799B - Hybrid control mechanism based on small helicopter - Google Patents
Hybrid control mechanism based on small helicopter Download PDFInfo
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- CN108839799B CN108839799B CN201810563948.6A CN201810563948A CN108839799B CN 108839799 B CN108839799 B CN 108839799B CN 201810563948 A CN201810563948 A CN 201810563948A CN 108839799 B CN108839799 B CN 108839799B
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C27/00—Rotorcraft; Rotors peculiar thereto
- B64C27/54—Mechanisms for controlling blade adjustment or movement relative to rotor head, e.g. lag-lead movement
- B64C27/58—Transmitting means, e.g. interrelated with initiating means or means acting on blades
- B64C27/59—Transmitting means, e.g. interrelated with initiating means or means acting on blades mechanical
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Abstract
The invention discloses a hybrid control mechanism based on a small helicopter, wherein the front end of a middle beam is rotatably connected with the middle part of a front beam, one side of the middle beam is provided with a single-degree-of-freedom connecting rod mechanism, the front end of the single-degree-of-freedom connecting rod mechanism is upwards connected with a first control rod, the rear end of the single-degree-of-freedom connecting rod mechanism is downwards connected with a first control rod, and the middle part of the middle beam is rotatably connected with a; one end of the front beam is upwards connected with a second control rod, the other end of the front beam is downwards connected with a second operating rod, a third control rod is upwards connected to the front beam positioned at the front end of the second operating rod, and a third operating rod is downwards connected to the rear end of the middle beam; the invention mixes three operation modes of transverse operation, longitudinal operation and total distance operation, simplifies the prior numerous and complicated mechanism, leads the mechanism to be more compact and occupy less space, has strong relevance of the three operation modes and high operation stability, and is more beneficial to the later inspection, maintenance and repair due to the structural simplification.
Description
Technical Field
The invention relates to the technical field of design and manufacture of aircrafts, in particular to a hybrid control mechanism based on a small helicopter.
Background
With the development of helicopter technology, electronic technology and control theory and the increasing demand for helicopter flight quality, the control system of the helicopter has experienced the development process from mechanical control to telex control and then to phototransmission control in decades.
The early helicopters used a simple mechanical control system, comprised of simple soft cables, pulleys, hard links, cranks and other mechanical components, and the pilot controlled the helicopter's automatic tillers and tail rotors by directly operating the mechanical drive system, achieving control of the helicopter's attitude and flight trajectory. Although this type of steering system has a simple and direct structure and high reliability, the pitching force of the rotor blades is transmitted to the steering column, so that the column force is large and a stick-shake is likely to occur, and the clearance, friction, and the like accumulated in the steering wire system are reflected on the steering column, which gives the driver a sense of discomfort and deteriorates the steering quality.
In order to solve the problems of the simple mechanical control system, most of the contemporary helicopters adopt a hydraulic power-assisted mechanical control system, which adds a hydraulic power-assisted system (servo mechanism) to the original simple mechanical control system, however, with the development of the helicopter design and the continuous improvement of the related technology, the contradiction between the stability and the maneuverability of the helicopter becomes more prominent, and a stability augmentation control system and a control stability augmentation control system appear in succession. These measures inevitably bring about insurmountable disadvantages, such as more complex mechanical linkages, heavier weight and more space occupation. Obviously, these drawbacks limit the designers to design optimal layouts for improving the performance of the helicopter according to the mission requirements, for which reason fly-by-wire systems have been developed.
Fly-by-wire systems can be defined as: the control command signal of the driver is only transmitted to the computer through a wire or a bus, and the computer generates an output command according to a preset rule to control the variable pitch of the rotor and the tail rotor so as to realize the control of the helicopter.
Disclosure of Invention
The invention aims to provide a hybrid control mechanism based on a small helicopter, which has a compact and small structure and occupies less space.
In order to achieve the purpose, the invention provides the following scheme:
the invention provides a hybrid control mechanism based on a small helicopter, which comprises a front beam and a middle beam, wherein the front end of the middle beam is rotatably connected with the middle part of the front beam, one side of the middle beam is provided with a single-degree-of-freedom connecting rod mechanism, the front end of the single-degree-of-freedom connecting rod mechanism is upwards connected with a first control rod, the rear end of the single-degree-of-freedom connecting rod mechanism is downwards connected with a first control rod, and the middle part of the middle beam is used for being rotatably connected with a lug of a helicopter body; one end of the front beam is upwards connected with a second control rod, the other end of the front beam is downwards connected with a second operating rod, the front beam positioned at the front end of the second operating rod is upwards connected with a third control rod, and the rear end of the middle beam is downwards connected with a third operating rod; the first control rod, the second control rod and the third control rod are all used for being connected with a tilter, and the first control rod, the second control rod and the third control rod are all used for being connected with a cabin control system.
Optionally, the center sill is an L-shaped center sill, the L-shaped center sill includes a long arm and a short arm, and the short arm is rotatably connected to the middle of the front beam through a first bolt.
Optionally, the single-degree-of-freedom link mechanism includes a front swing arm, a connecting rod, and a rear swing arm, the front swing arm is rotatably connected to the front portion of the long arm through a second bolt, the rear swing arm is rotatably connected to the rear portion of the long arm through a third bolt, the rear end of the front swing arm is connected to the front end of the rear swing arm through the connecting rod, the front end of the front swing arm is rotatably connected to the first control rod, and the rear end of the rear swing arm is rotatably connected to the first control rod.
Optionally, a first bearing is arranged on the second bolt located at the joint of the front swing arm and the long arm, and the first bearing is used for the front swing arm to make fixed-axis rotation; and a second bearing is arranged on the third bolt at the joint of the rear swing arm and the long arm, and the second bearing is used for the rear swing arm to rotate in a fixed shaft mode.
Optionally, the front beam is an arc-shaped front beam, the middle beam is located on the inner side of the arc-shaped front beam, and the second control rod and the third control rod are symmetrically arranged along the axis of the first bolt.
Optionally, the second control rod, the third control rod and the second operating rod are all rotatably connected with the front beam through bolts; the first operating rod and the first control rod are both rotatably connected with the single-degree-of-freedom link mechanism through bolts; the third operating rod is rotatably connected with the centre sill through a bolt.
Optionally, the centre sill is rotatably connected to the fuselage lug by a bolt.
Optionally, the center sill is rotatably connected to the fuselage lug through the second bolt or the third bolt.
Compared with the prior art, the invention has the following technical effects:
the hybrid control mechanism based on the small helicopter has the advantages that three control modes of transverse control, longitudinal control and total distance control are mixed, the traditional complicated mechanism is simplified, the mechanism is more compact, the occupied space is less, the three control modes have strong relevance and high control stability, the structural simplification is more favorable for later inspection, maintenance and repair, and the problems of high mechanism dispersity and large occupied space caused by the fact that the transverse control, the longitudinal control and the total distance control in the prior art are completed by independent mechanisms are effectively solved.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without inventive exercise.
FIG. 1 is a schematic view of the installation position of the hybrid control mechanism based on a small helicopter in the fuselage of the present invention;
FIG. 2 is a schematic view of a hybrid operating mechanism based on a small helicopter according to the present invention;
FIG. 3 is a functional implementation schematic diagram of a hybrid control mechanism based on a small helicopter according to the present invention;
FIG. 4 is a schematic view of the hybrid operating mechanism of the present invention in a balanced position;
FIG. 5 is a schematic view of the hybrid steering mechanism for a small helicopter according to the present invention for longitudinal steering;
FIG. 6 is a schematic view of a hybrid control mechanism for a small helicopter according to the present invention for collective control;
wherein the reference numerals are: 1. a front beam; 2. a middle beam; 3. a fuselage tab; 4. a first control lever; 5. a second control lever; 6. a third control lever; 7. a first joystick; 8. a second joystick; 9. a third joystick; 10. a single degree of freedom linkage mechanism; 101. a front swing arm; 102. a connecting rod; 103. a rear swing arm; 11. a first bolt; 12. a second bolt; 13. a third bolt; 14. a tilter; 15. a nacelle handling system; 16. a blade.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The invention aims to provide a hybrid control mechanism based on a small helicopter, which has a compact and small structure and occupies less space.
Based on the above, the invention provides a hybrid control mechanism based on a small helicopter, which comprises a front beam and a middle beam, wherein the front end of the middle beam is rotatably connected with the middle part of the front beam, one side of the middle beam is provided with a single-degree-of-freedom connecting rod mechanism, the front end of the single-degree-of-freedom connecting rod mechanism is upwards connected with a first control rod, the rear end of the single-degree-of-freedom connecting rod mechanism is downwards connected with a first control rod, and the middle part of the middle beam is rotatably connected with a lug of a helicopter body; one end of the front beam is upwards connected with a second control rod, the other end of the front beam is downwards connected with a second operating rod, the front beam positioned at the front end of the second operating rod is upwards connected with a third control rod, and the rear end of the middle beam is downwards connected with a third operating rod; the first control rod, the second control rod and the third control rod are all used for being connected with the tilter, and the first control rod, the second control rod and the third control rod are all used for being connected with a cabin control system.
The hybrid control mechanism based on the small helicopter has the advantages that three control modes of transverse control, longitudinal control and total distance control are mixed, the traditional complicated mechanism is simplified, the mechanism is more compact, the occupied space is less, the three control modes have strong relevance and high control stability, the structural simplification is more favorable for later inspection, maintenance and repair, and the problems of high mechanism dispersity and large occupied space caused by the fact that the transverse control, the longitudinal control and the total distance control in the prior art are completed by independent mechanisms are effectively solved.
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in further detail below.
The first embodiment is as follows:
as shown in fig. 1-2, the embodiment provides a hybrid control mechanism based on a small helicopter, which includes a front beam 1 and a middle beam 2, wherein the front end of the middle beam 2 is rotatably connected with the middle part of the front beam 1, a single-degree-of-freedom link mechanism 10 is installed on one side of the middle beam 2, the front end of the single-degree-of-freedom link mechanism 10 is upwardly connected with a first control rod 4, the rear end of the single-degree-of-freedom link mechanism 10 is downwardly connected with the first control rod 4, and the middle part of the middle beam 2 is rotatably connected with a fuselage lug 3 through a bolt; one end of the front beam 1 is connected with a second control rod 5 upwards, the other end of the front beam 1 is connected with a second operating rod 8 downwards, and the front beam 1 at the front end of the second operating rod 8 is connected with a third control rod 6 upwards, namely as shown in fig. 2, the second control rod 5, the second operating rod 8 and the third control rod 6 are all connected on the front beam 1, and the third control rod 6 is positioned between the second control rod 5 and the second operating rod 8; the rear end of the middle beam 2 is downwards connected with a third operating lever 9; as shown in fig. 3, the first control lever 4, the second control lever 5 and the third control lever 6 are each connected to a tilter 14 via a relevant link, the first control lever 7, the second control lever 8 and the third control lever 9 are each connected to a nacelle operating system 15 via a relevant link, and a blade 16 is also connected above the tilter 14 via a relevant link.
In this embodiment, as shown in fig. 2, the center sill 2 is an L-shaped center sill, and the L-shaped center sill includes a long arm and a short arm, and the short arm is rotatably connected to the middle of the front sill 1 through a first bolt 11. Furthermore, as shown in fig. 2, the single-degree-of-freedom link mechanism 10 includes a front swing arm 101, a connecting rod 102 and a rear swing arm 103, the front swing arm 101 is rotatably connected to the front portion of the L-shaped middle beam long arm through a second bolt 12, the rear swing arm 103 is rotatably connected to the rear portion of the L-shaped middle beam long arm through a third bolt 13, the rear end of the front swing arm 101 and the front end of the rear swing arm 103 are connected through the connecting rod 102, the connecting rod 102 and the front swing arm 101 and the rear swing arm 103 are both bolted, the front end of the front swing arm 101 is rotatably connected to the first control lever 4, the rear end of the rear swing arm 103 is rotatably connected to the first control lever 7, and the single-degree-of-freedom link mechanism 10 is configured to ensure that the first control lever 4 is parallel to the first control lever 7 and both are perpendicular to.
Further, as shown in fig. 1-2, a first bearing is arranged on a second bolt 12 located at a connection position of the front swing arm 101 and the long arm of the L-shaped center sill, and the first bearing is used for the front swing arm 101 to make fixed-axis rotation; correspondingly, a second bearing is arranged on a third bolt 13 positioned at the joint of the rear swing arm 103 and the long arm of the L-shaped middle beam, and the second bearing is used for the rear swing arm 103 to rotate in a fixed axis mode.
Further, as shown in fig. 1 to 2, the front beam 1 is an arc-shaped front beam, the middle beam 2 is located on the inner side of an arc of the arc-shaped front beam, the second control rod 5 and the third control rod 6 are symmetrically arranged along a straight line where an axis of the first bolt 11 is located, the third control rod 6 and the second control rod 8 respectively occupy two end points of the front beam 1, and the second control rod 8 is located at an end point of the front beam 1, so that the control sensitivity of the second control rod 8 is improved.
Further, as shown in fig. 2, the second control lever 5, the third control lever 6 and the second operating lever 5 are rotatably connected to the front beam 1 by bolts; the first operating rod 7 and the first control rod 4 are respectively in rotatable connection with two ends of the single-degree-of-freedom link mechanism 10 through bolts; the third operating rod 9 is rotatably connected with the rear end point of the center sill 2 through a bolt.
Further, the centre sill 2 can be rotatably connected with the fuselage lug 3 through the second bolt 12 or the third bolt 13, which is beneficial to improving the structural compactness of the hybrid control mechanism.
The following description will use the present embodiment with the transverse steering, the longitudinal steering and the collective steering as examples respectively:
the transverse manipulation process comprises the following steps:
as shown in fig. 4, the whole hybrid control mechanism is in a balanced state, the middle beam 2 is fixed on the lug plate 3 of the machine body through the third bolt 13, the front beam 1 is rotatably connected with the middle beam 2 through the first bolt 11 in the middle, and the front beam 1 can make fixed-axis rotation around the axis of the first bolt 11. The second operating rod 8 is driven to move up and down by operating the cabin operating system 15, and the middle beam 2 is fixed at the moment, so that the second operating rod 8 drives the front beam 1 to rotate around the fixed shaft of the axis of the third bolt 13, and further drives the second control rod 5 and the third control rod 6, and thus, the transverse operation is realized.
(II) a longitudinal manipulation process;
based on the balance state shown in fig. 4, the cabin control system 15 is operated to drive the first control lever 7 to move vertically downward, so as to sequentially drive the rear swing arm 103, the connecting rod 102 and the front swing arm 101 to perform corresponding linkage, and further drive the first control lever 4 to move vertically upward, as shown in fig. 5, thereby realizing the control of the longitudinal movement of the tilter 14 by the cabin control system 15, and finally realizing the longitudinal control.
(III) a collective pitch control process:
also based on the balance state shown in fig. 4, the third operating lever 9 is pulled to move downwards by operating the nacelle operating system 15, and since the center sill 2 is connected to the fuselage lug 3 through the third bolt 13, the center sill 2 together with the whole hybrid operating mechanism simultaneously rotates around the fixed axis of the third bolt 13 under the pulling action of the third operating lever 9, as shown in fig. 6, and through the transmission of the three control levers, the vertical translation of the tilter 14 is finally realized, and the purpose of operating the total pitch is achieved.
Therefore, the three operation modes of transverse operation, longitudinal operation and total distance operation are mixed, the previous complicated mechanism is simplified, the mechanism is more compact, the occupied space is less, the relevance of the three operation modes is strong, the operation stability is high, the structural simplification is more favorable for later inspection, maintenance and repair, and the problems of high mechanism dispersity and large occupied space caused by the fact that the transverse operation, the longitudinal operation and the total distance operation need to be completed by separate mechanisms in the prior art are effectively solved.
The principle and the implementation mode of the invention are explained by applying a specific example, and the description of the embodiment is only used for helping to understand the method and the core idea of the invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, the specific embodiments and the application range may be changed. In view of the above, the present disclosure should not be construed as limiting the invention.
Claims (8)
1. A hybrid control mechanism based on a small helicopter is characterized in that: the single-freedom-degree control mechanism comprises a front beam and a middle beam, wherein the front end of the middle beam is rotatably connected with the middle part of the front beam, a single-freedom-degree connecting rod mechanism is installed on one side of the middle beam, the front end of the single-freedom-degree connecting rod mechanism is upwards connected with a first control rod, the rear end of the single-freedom-degree connecting rod mechanism is downwards connected with a first control rod, and the middle part of the middle beam is rotatably connected with a lug of a machine body; one end of the front beam is upwards connected with a second control rod, the other end of the front beam is downwards connected with a second operating rod, the front beam positioned at the front end of the second operating rod is upwards connected with a third control rod, and the rear end of the middle beam is downwards connected with a third operating rod; the first control rod, the second control rod and the third control rod are all used for being connected with a tilter, and the first control rod, the second control rod and the third control rod are all used for being connected with a cabin control system; the middle beam is an L-shaped middle beam, the L-shaped middle beam comprises a long arm and a short arm, and the short arm is rotatably connected with the front beam; the single-degree-of-freedom link mechanism comprises a front swing arm, a connecting rod and a rear swing arm, the front swing arm is rotatably connected to the front portion of the long arm, the rear swing arm is rotatably connected to the rear portion of the long arm, the rear end of the front swing arm is connected with the front end of the rear swing arm through the connecting rod, the front end of the front swing arm is rotatably connected with the first control rod, and the rear end of the rear swing arm is rotatably connected with the first control rod.
2. The hybrid control mechanism for small helicopters according to claim 1, characterized in that: the short arm is rotatably connected with the middle part of the front beam through a first bolt.
3. The hybrid steering mechanism for small helicopters according to claim 2, characterized in that: the front swing arm is rotatably connected to the front part of the long arm through a second bolt, and the rear swing arm is rotatably connected to the rear part of the long arm through a third bolt.
4. The hybrid steering mechanism for small helicopters according to claim 3, characterized in that: a first bearing is arranged on the second bolt at the joint of the front swing arm and the long arm, and the first bearing is used for the front swing arm to make fixed-axis rotation; and a second bearing is arranged on the third bolt at the joint of the rear swing arm and the long arm, and the second bearing is used for the rear swing arm to rotate in a fixed shaft mode.
5. The hybrid steering mechanism for small helicopters according to claim 2, characterized in that: the front beam is an arc-shaped front beam, the middle beam is positioned on the inner side of the arc-shaped front beam, and the second control rod and the third control rod are symmetrically arranged along the axis of the first bolt.
6. The hybrid control mechanism for small helicopters according to claim 1, characterized in that: the second control rod, the third control rod and the second operating rod are all rotatably connected with the front beam through bolts; the first operating rod and the first control rod are both rotatably connected with the single-degree-of-freedom link mechanism through bolts; the third operating rod is rotatably connected with the centre sill through a bolt.
7. The hybrid control mechanism for small helicopters according to claim 1, characterized in that: the middle beam is rotatably connected with the lug of the machine body through a bolt.
8. The hybrid steering mechanism for small helicopters according to claim 3, characterized in that: the middle beam is rotatably connected with the lug plate of the machine body through the second bolt or the third bolt.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810563948.6A CN108839799B (en) | 2018-06-04 | 2018-06-04 | Hybrid control mechanism based on small helicopter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810563948.6A CN108839799B (en) | 2018-06-04 | 2018-06-04 | Hybrid control mechanism based on small helicopter |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108839799A CN108839799A (en) | 2018-11-20 |
| CN108839799B true CN108839799B (en) | 2020-03-20 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201810563948.6A Active CN108839799B (en) | 2018-06-04 | 2018-06-04 | Hybrid control mechanism based on small helicopter |
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Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3095931A (en) * | 1961-05-10 | 1963-07-02 | Kaman Aircraft Corp | Blade pitch control mechanism for a helicopter |
| US3228478A (en) * | 1964-04-29 | 1966-01-11 | Bell Aerospace Corp | Control lag compensator for rotary wing aircraft |
| US5597138A (en) * | 1991-09-30 | 1997-01-28 | Arlton; Paul E. | Yaw control and stabilization system for helicopters |
| CN101134506A (en) * | 2007-08-27 | 2008-03-05 | 万涛 | Helicopter rotor control mechanism |
| FR3027871B1 (en) * | 2014-10-30 | 2018-03-23 | Airbus Helicopters | MECHANICAL DEVICE FOR COMBINING AT LEAST ONE FIRST ORDER AND A SECOND ORDER ORDER, AND AN AIRCRAFT PROVIDED WITH SUCH A DEVICE |
| CN105217025A (en) * | 2015-11-09 | 2016-01-06 | 德奥通用航空股份有限公司 | A kind of aircraft coaxial double-rotary wing system |
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2018
- 2018-06-04 CN CN201810563948.6A patent/CN108839799B/en active Active
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