CN113928543B - Helicopter undercarriage retraction control system - Google Patents
Helicopter undercarriage retraction control system Download PDFInfo
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- CN113928543B CN113928543B CN202111381838.6A CN202111381838A CN113928543B CN 113928543 B CN113928543 B CN 113928543B CN 202111381838 A CN202111381838 A CN 202111381838A CN 113928543 B CN113928543 B CN 113928543B
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- valve
- port
- landing gear
- control valve
- retraction
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C25/00—Alighting gear
- B64C25/02—Undercarriages
- B64C25/08—Undercarriages non-fixed, e.g. jettisonable
- B64C25/10—Undercarriages non-fixed, e.g. jettisonable retractable, foldable, or the like
- B64C25/18—Operating mechanisms
- B64C25/22—Operating mechanisms fluid
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C25/00—Alighting gear
- B64C25/02—Undercarriages
- B64C25/08—Undercarriages non-fixed, e.g. jettisonable
- B64C25/10—Undercarriages non-fixed, e.g. jettisonable retractable, foldable, or the like
- B64C25/18—Operating mechanisms
- B64C25/26—Control or locking systems therefor
- B64C25/28—Control or locking systems therefor with indicating or warning devices
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T50/00—Aeronautics or air transport
- Y02T50/40—Weight reduction
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Aviation & Aerospace Engineering (AREA)
- Fluid-Pressure Circuits (AREA)
Abstract
The application provides a helicopter landing gear retraction control system which comprises a retraction electromagnetic valve 1, a landing gear control valve 2, a landing gear bypass valve 3, a throttle valve 4, a landing gear retraction actuator 5, an emergency discharge magnetic valve 6, an emergency deflation bottle 7, a pressure gauge 8, a reciprocating valve 9, a one-way throttle valve 10, a retraction electromagnetic valve 11 and a bypass control valve 12. The landing gear can be controlled to retract and retract, kept in a retracted position or a retracted position, and has an emergency landing gear retraction control function when the hydraulic source loses pressure or the landing gear control valve 2 fails and cannot return oil.
Description
Technical Field
The application relates to the field of helicopters, in particular to a helicopter landing gear retraction control system.
Background
With the development of helicopter technology, it is increasingly necessary to retract and extend the landing gear of the helicopter so as to reduce the aerodynamic resistance of the helicopter and meet the requirement of front flying speed. Landing gear retraction system is an important system that directly affects helicopter safety.
The existing helicopter adopts hydraulic control to carry out normal retraction and emergency release of the landing gear, and the hydraulic control has the characteristics of stable operation, large bearing capacity, small volume, light weight and the like, but is easy to leak, and the hydraulic element has high manufacturing precision requirement and high maintenance requirement.
Disclosure of Invention
The application provides a helicopter landing gear retraction control system, which is characterized in that the landing gear is hydraulically controlled during normal retraction and emergency retraction, pneumatic control is adopted during emergency retraction, and redundancy design of different energy sources is adopted during landing gear retraction, so that flight safety is improved, and maintenance is convenient.
Technical problems: the application provides a helicopter landing gear retraction control system, which comprises a retraction electromagnetic valve 1, a landing gear control valve 2, a landing gear bypass valve 3, a throttle valve 4, a landing gear retraction actuator 5, an emergency discharging magnetic valve 6, an emergency discharging bottle 7, a pressure gauge 8, a reciprocating valve 9, a one-way throttle valve 10, a retraction electromagnetic valve 11 and a bypass control valve 12, wherein:
the pressure supply port of the hydraulic source is a P port, and the oil return port is an R port; the P port of the stowing electromagnetic valve 1, the P port of the lowering electromagnetic valve 11, the P port of the landing gear control valve 2 and the P port of the bypass control valve 12 are respectively connected to the P port of the hydraulic source; the R port of the stowing electromagnetic valve 1, the R port of the lowering electromagnetic valve 11, the R port of the landing gear control valve 2, the R port of the bypass control valve 12 and the R port of the landing gear bypass valve 3 are respectively connected to the R port of the hydraulic source; the A port of the stowing electromagnetic valve 1 is connected to the K2 port of the landing gear control valve 2, the A port of the lowering electromagnetic valve 11 is connected to the K1 port of the landing gear control valve 2, and the A port of the bypass control valve 12 is connected to the K port of the landing gear bypass valve 3; the A port of the landing gear control valve 2 is connected to the one-way throttle valve 10, and the B port of the landing gear control valve 2 is connected to the P port of the landing gear bypass valve 3; the A port of the landing gear bypass valve 3 is connected to three throttle valves 4, and the three throttle valves 4 are respectively connected to the retraction cavities of three landing gear retraction actuators 5; the one-way throttle valve 10 is connected to an A port of the reciprocating valve 9, and a C port of the reciprocating valve 9 is connected to the lowering cavities of the three landing gear retracting cylinders 5; the emergency gas discharge bottle 7 and the pressure gauge 8 are connected to the P port of the emergency discharge magnetic valve 6, the R port of the emergency discharge magnetic valve 6 is connected to the gas discharge port, and the a port of the emergency discharge magnetic valve 6 is connected to the B port of the shuttle valve 9.
Specifically, the stowing solenoid valve 1, the emergency discharging solenoid valve 6, the lowering solenoid valve 11 and the bypass control valve 12 are two-position three-way solenoid valves.
Specifically, the landing gear control valve 2 is a pilot-operated three-position four-way reversing valve, and the position change is realized under the action of pressure difference of two ends by comparing the pressures of the K1 port and the K2 port. The landing gear bypass valve 3 is a pilot type two-position single-pass reversing valve, and position change is realized by comparing the K-port pressure with the size in the spring.
Specifically, when the landing gear is in the down position, the stowing solenoid valve 1 is in the de-energized state, the emergency discharge solenoid valve 6 is in the de-energized state, the down solenoid valve 11 is in the de-energized state, and the bypass control valve 12 is in the de-energized state.
Specifically, when landing gear stowing is performed, the stowing solenoid valve 1 is switched to an energized state, and the emergency discharge solenoid valve 6, the lowering solenoid valve 11, and the bypass control valve 12 are in a still-deenergized state. The hydraulic pressure source gets into undercarriage receive and release control system from P mouth department, and the high pressure oil way is through packing up solenoid valve 1, gets into the K2 mouth of undercarriage control valve 2, and under the pressure differential in K1 mouth and K2 mouthful both ends of undercarriage control valve 2, the case of undercarriage control valve 2 slides to K1 mouthful one end, and the high pressure oil way of system is through undercarriage control valve 2, gets into in three oil ways, provides the hydraulic energy for three undercarriage packing up the chamber respectively.
Specifically, when the landing gear is normally put down, the down electromagnetic valve 11 is switched to an energized state, and the emergency discharge electromagnetic valve 6, the stowing electromagnetic valve 1 and the bypass control valve 12 are in a still-off state. The hydraulic pressure source gets into undercarriage receive and release control system from P mouth department, and the high pressure oil way is through putting down solenoid valve 11, gets into the K1 mouth of undercarriage control valve 2, and under the pressure differential in the K1 mouth and the K2 mouth both ends of undercarriage control valve 2, the case of undercarriage control valve 2 slides to K2 mouth one end, and the high pressure oil way of system is through undercarriage control valve 2, gets into in three oil ways, provides the hydraulic energy for three undercarriage cavity of putting down respectively.
Specifically, when the hydraulic pressure source loses pressure or the landing gear control valve 2 fails and cannot return oil, the emergency discharging solenoid valve 6 and the bypass control valve 12 are switched to the energized state, and the stowing solenoid valve 1 and the lowering solenoid valve 11 are in the still-energized state. The high-pressure hydraulic oil in the emergency release cylinder 7 passes through the emergency release magnetic valve 6 and the reciprocating valve 9 to provide energy for the landing gear release cavity.
Specifically, the two chambers of the landing gear retraction jack 5 provide a position locking function and a position warning function.
In summary, according to the landing gear retraction control system, the safety requirements of retraction of the landing gear are considered, and different energy sources are adopted as driving to realize redundancy design. The normal retraction adopts hydraulic drive, and a pilot type electromagnetic reversing valve is adopted, so that the hydraulic lifting jack has the advantages of small volume, high power-weight ratio, safety, reliability and the like. The emergency setting down adopts pneumatic control, and has the advantages of small resistance, simple maintenance, safe use and the like.
Drawings
Fig. 1 is a schematic diagram of a helicopter landing gear retraction control system according to an embodiment of the present application.
Wherein: the hydraulic lifting device comprises a 1-stowing electromagnetic valve, a 2-landing gear control valve, a 3-landing gear bypass valve, a 4-throttle valve, a 5-landing gear stowing and releasing actuator cylinder, a 6-emergency discharging magnetic valve 7-emergency discharging gas cylinder, an 8-pressure gauge, a 9-reciprocating valve, a 10-one-way throttle valve, an 11-lowering electromagnetic valve and a 12-bypass control valve.
Detailed Description
The application aims to provide a helicopter landing gear control system with different energy redundancy designs aiming at the existing helicopter landing gear retraction control system, hydraulic control is adopted when the helicopter is normally retracted and extended, the helicopter landing gear retraction control system is stable and reliable, the weight is light, and when an on-board hydraulic source fails or the landing gear can not be normally retracted, pneumatic control is adopted to emergency-retract the landing gear.
As shown in fig. 1, the helicopter landing gear retraction control system comprises a retraction electromagnetic valve 1, a landing gear control valve 2, a landing gear bypass valve 3, a throttle valve 4, a landing gear retraction actuator 5, an emergency discharge magnetic valve 6, an emergency deflation bottle 7, a pressure gauge 8, a reciprocating valve 9, a one-way throttle valve 10, a retraction electromagnetic valve 11 and a bypass control valve 12.
The hydraulic oil return port is an R port; the P port of the stowing electromagnetic valve 1, the P port of the lowering electromagnetic valve 11, the P port of the landing gear control valve 2 and the P port of the bypass control valve 12 are respectively connected to the P port of the hydraulic source; the R port of the stowing electromagnetic valve 1, the R port of the lowering electromagnetic valve 11, the R port of the landing gear control valve 2, the R port of the bypass control valve 12 and the R port of the landing gear bypass valve 3 are respectively connected to the R port of the hydraulic source; the A port of the stowing electromagnetic valve 1 is connected to the K2 port of the landing gear control valve 2, the A port of the lowering electromagnetic valve 11 is connected to the K1 port of the landing gear control valve 2, and the A port of the bypass control valve 12 is connected to the K port of the landing gear bypass valve 3; the A port of the landing gear control valve 2 is connected to the one-way throttle valve 10, and the B port of the landing gear control valve 2 is connected to the P port of the landing gear bypass valve 3; the A port of the landing gear bypass valve 3 is connected to three throttle valves 4, and the three throttle valves 4 are respectively connected to the retraction cavities of three landing gear retraction actuators 5; the one-way throttle valve 10 is connected to an A port of the reciprocating valve 9, and a C port of the reciprocating valve 9 is connected to the lowering cavities of the three landing gear retracting cylinders 5; the emergency gas discharge bottle 7 and the pressure gauge 8 are connected to the P port of the emergency discharge magnetic valve 6, the R port of the emergency discharge magnetic valve 6 is connected to the gas discharge port, and the a port of the emergency discharge magnetic valve 6 is connected to the B port of the shuttle valve 9.
It should be noted that, each part in the helicopter undercarriage retraction control system is connected through the pipeline.
In practical application, the pressure gauge 8 is provided with an air charging nozzle.
Specifically, the stowing solenoid valve 1, the emergency discharging solenoid valve 6, the lowering solenoid valve 11 and the bypass control valve 12 are two-position three-way solenoid valves.
Specifically, the landing gear control valve 2 is a pilot-operated three-position four-way reversing valve, and the position change is realized under the action of pressure difference of two ends by comparing the pressures of the K1 port and the K2 port. The landing gear bypass valve 3 is a pilot type two-position single-pass reversing valve, and position change is realized by comparing the K-port pressure with the size in the spring.
Specifically, when the landing gear is in the down position, the stowing solenoid valve 1 is in the de-energized state, the emergency discharge solenoid valve 6 is in the de-energized state, the down solenoid valve 11 is in the de-energized state, and the bypass control valve 12 is in the de-energized state.
Specifically, when landing gear stowing is performed, the stowing solenoid valve 1 is switched to an energized state, and the emergency discharge solenoid valve 6, the lowering solenoid valve 11, and the bypass control valve 12 are in a still-deenergized state. The hydraulic pressure source gets into undercarriage receive and release control system from P mouth department, and the high pressure oil way is through packing up solenoid valve 1, gets into the K2 mouth of undercarriage control valve 2, and under the pressure differential in K1 mouth and K2 mouthful both ends of undercarriage control valve 2, the case of undercarriage control valve 2 slides to K1 mouthful one end, and the high pressure oil way of system is through undercarriage control valve 2, gets into in three oil ways, provides the hydraulic energy for three undercarriage packing up the chamber respectively.
Specifically, when the landing gear is normally put down, the down electromagnetic valve 11 is switched to an energized state, and the emergency discharge electromagnetic valve 6, the stowing electromagnetic valve 1 and the bypass control valve 12 are in a still-off state. The hydraulic pressure source gets into undercarriage receive and release control system from P mouth department, and the high pressure oil way is through putting down solenoid valve 11, gets into the K1 mouth of undercarriage control valve 2, and under the pressure differential in the K1 mouth and the K2 mouth both ends of undercarriage control valve 2, the case of undercarriage control valve 2 slides to K2 mouth one end, and the high pressure oil way of system is through undercarriage control valve 2, gets into in three oil ways, provides the hydraulic energy for three undercarriage cavity of putting down respectively.
Specifically, when the hydraulic pressure source loses pressure or the landing gear control valve 2 fails and cannot return oil, the emergency discharging solenoid valve 6 and the bypass control valve 12 are switched to the energized state, and the stowing solenoid valve 1 and the lowering solenoid valve 11 are in the still-energized state. The high-pressure hydraulic oil in the emergency release cylinder 7 passes through the emergency release magnetic valve 6 and the reciprocating valve 9 to provide energy for the landing gear release cavity.
Specifically, the two chambers of the landing gear retraction jack 5 provide a position locking function and a position warning function.
In summary, according to the landing gear retraction control system, the safety requirements of retraction of the landing gear are considered, and different energy sources are adopted as driving to realize redundancy design. The normal retraction adopts hydraulic drive, and a pilot type electromagnetic reversing valve is adopted, so that the hydraulic lifting jack has the advantages of small volume, high power-weight ratio, safety, reliability and the like. The emergency setting down adopts pneumatic control, and has the advantages of small resistance, simple maintenance, safe use and the like.
Claims (5)
1. The helicopter undercarriage retraction control system is characterized by comprising a retraction electromagnetic valve (1), an undercarriage control valve (2), an undercarriage bypass valve (3), a throttle valve (4), an undercarriage retraction actuator cylinder (5), an emergency discharge magnetic valve (6), an emergency deflation bottle (7), a pressure gauge (8), a reciprocating valve (9), a unidirectional throttle valve (10), a retraction electromagnetic valve (11) and a bypass control valve (12), wherein:
the pressure supply port of the hydraulic source is a P port, and the oil return port is an R port; the P port of the stowing electromagnetic valve (1), the P port of the lowering electromagnetic valve (11), the P port of the landing gear control valve (2) and the P port of the bypass control valve (12) are respectively connected to the P port of the hydraulic source; the R port of the stowing electromagnetic valve (1), the R port of the lowering electromagnetic valve (11), the R port of the landing gear control valve (2), the R port of the bypass control valve (12) and the R port of the landing gear bypass valve (3) are respectively connected to the R port of the hydraulic source; an A port of the stowing electromagnetic valve (1) is connected to a K2 port of the landing gear control valve (2), an A port of the lowering electromagnetic valve (11) is connected to a K1 port of the landing gear control valve (2), and an A port of the bypass control valve (12) is connected to a K port of the landing gear bypass valve (3); the A port of the landing gear control valve (2) is connected to the one-way throttle valve (10), and the B port of the landing gear control valve (2) is connected to the P port of the landing gear bypass valve (3); the A port of the landing gear bypass valve (3) is connected to three throttle valves (4), and the three throttle valves (4) are respectively connected to the retraction cavities of the three landing gear retraction actuators (5); the one-way throttle valve (10) is connected to an A port of the reciprocating valve (9), and a C port of the reciprocating valve (9) is connected to the lowering cavities of the three landing gear retracting cylinders (5); the emergency gas discharge bottle (7) and the pressure gauge (8) are connected to the P port of the emergency discharge magnetic valve (6), the R port of the emergency discharge magnetic valve (6) is connected to the gas outlet, and the A port of the emergency discharge magnetic valve (6) is connected to the B port of the reciprocating valve (9);
when the landing gear is retracted, the retraction electromagnetic valve (1) is converted into an electrified state, and the emergency discharging electromagnetic valve (6), the lowering electromagnetic valve (11) and the bypass control valve (12) are in a still power-off state; the hydraulic source enters the landing gear retraction control system from the P port, the high-pressure oil way passes through the retraction electromagnetic valve (1), enters the K2 port of the landing gear control valve (2), and under the pressure difference between the K1 port and the K2 port of the landing gear control valve (2), the valve core of the landing gear control valve (2) slides to one end of the K1 port, and the high-pressure oil way of the system passes through the landing gear control valve (2) and enters three oil ways to respectively provide hydraulic energy for three landing gear retraction cavities;
when the landing gear is normally put down, the down electromagnetic valve (11) is converted into an electrified state, and the emergency discharging electromagnetic valve (6), the stowing electromagnetic valve (1) and the bypass control valve (12) are in a still power-off state; the hydraulic source enters the landing gear retraction control system from the P port, the high-pressure oil way passes through the retraction electromagnetic valve (11), enters the K1 port of the landing gear control valve (2), the valve core of the landing gear control valve (2) slides to one end of the K2 port under the pressure difference between the K1 port and the K2 port of the landing gear control valve (2), and the high-pressure oil way of the system passes through the landing gear control valve (2) and enters three oil ways to respectively provide hydraulic energy for three landing gear retraction cavities;
when the hydraulic source loses pressure or the landing gear control valve (2) fails and cannot return oil, the emergency discharging solenoid valve (6) and the bypass control valve (12) are switched to an electrified state, and the retracting solenoid valve (1) and the lowering solenoid valve (11) are in a still power-off state; the high-pressure hydraulic oil in the emergency release cylinder (7) passes through the emergency release magnetic valve (6) and the reciprocating valve (9) to provide energy for the landing gear release cavity.
2. The system according to claim 1, characterized in that the stow solenoid valve (1), the emergency discharge solenoid valve (6), the drop solenoid valve (11) and the bypass control valve (12) are two-position three-way solenoid valves.
3. The system according to claim 1, characterized in that the landing gear control valve (2) is a pilot-operated three-position four-way reversing valve; the landing gear bypass valve (3) is a pilot type two-position single-pass reversing valve.
4. A system according to claim 1, characterized in that when the landing gear is in the down position, the stow solenoid valve (1) is in the de-energized state, the emergency discharge solenoid valve (6) is in the de-energized state, the down solenoid valve (11) is in the de-energized state, and the bypass control valve (12) is in the de-energized state.
5. A system according to claim 1, wherein the two chambers of the landing gear retraction ram (5) provide a position locking function and a position warning function.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111381838.6A CN113928543B (en) | 2021-11-19 | 2021-11-19 | Helicopter undercarriage retraction control system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111381838.6A CN113928543B (en) | 2021-11-19 | 2021-11-19 | Helicopter undercarriage retraction control system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113928543A CN113928543A (en) | 2022-01-14 |
| CN113928543B true CN113928543B (en) | 2023-09-08 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202111381838.6A Active CN113928543B (en) | 2021-11-19 | 2021-11-19 | Helicopter undercarriage retraction control system |
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB557525A (en) * | 1942-05-20 | 1943-11-24 | Rubery Owen Messier Ltd | Improvements in or relating to distant control gear for use on aircraft |
| CN101025128A (en) * | 2006-02-24 | 2007-08-29 | 同济大学 | Axial symmetric vector spray-pipe A9 action emergency resetting hydraulic system |
| CN208544412U (en) * | 2018-06-04 | 2019-02-26 | 四川航泰航空装备有限公司 | A kind of comprehensive folding and unfolding brake dual system of unmanned plane undercarriage |
| CN109733594A (en) * | 2019-03-06 | 2019-05-10 | 成都飞机工业（集团）有限责任公司 | A kind of cold air operation of landing gear system and its method of rising and falling |
| CN112173085A (en) * | 2020-09-25 | 2021-01-05 | 中国直升机设计研究所 | Hydraulic control system and method for retraction and release of helicopter undercarriage |
| CN113148118A (en) * | 2021-05-10 | 2021-07-23 | 四川凌峰航空液压机械有限公司 | Hydraulic retraction system capable of locking undercarriage at any required position |
-
2021
- 2021-11-19 CN CN202111381838.6A patent/CN113928543B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB557525A (en) * | 1942-05-20 | 1943-11-24 | Rubery Owen Messier Ltd | Improvements in or relating to distant control gear for use on aircraft |
| CN101025128A (en) * | 2006-02-24 | 2007-08-29 | 同济大学 | Axial symmetric vector spray-pipe A9 action emergency resetting hydraulic system |
| CN208544412U (en) * | 2018-06-04 | 2019-02-26 | 四川航泰航空装备有限公司 | A kind of comprehensive folding and unfolding brake dual system of unmanned plane undercarriage |
| CN109733594A (en) * | 2019-03-06 | 2019-05-10 | 成都飞机工业（集团）有限责任公司 | A kind of cold air operation of landing gear system and its method of rising and falling |
| CN112173085A (en) * | 2020-09-25 | 2021-01-05 | 中国直升机设计研究所 | Hydraulic control system and method for retraction and release of helicopter undercarriage |
| CN113148118A (en) * | 2021-05-10 | 2021-07-23 | 四川凌峰航空液压机械有限公司 | Hydraulic retraction system capable of locking undercarriage at any required position |
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| Publication number | Publication date |
|---|---|
| CN113928543A (en) | 2022-01-14 |
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