Hydraulic energy switching control valve and method for landing gear retraction and extension system

Abstract

The present invention belongs to the technical field of aircraft hydraulic valves and discloses a hydraulic energy switching control valve and method for a landing gear retraction and extension system. The control valve includes a valve body, a pilot solenoid valve, and a shuttle valve. The valve body contains a load chamber, a backup oil inlet chamber, a backup pressure chamber, a backup oil return chamber, an oil return chamber, a main oil return chamber, a main pressure chamber, and a main oil inlet chamber. When the pilot solenoid valve is in position 0, it is in a state where the main hydraulic source supplies pressure, at which point the main pressure chamber and the load chamber are connected. When the pilot solenoid valve is in position 1, it is in a state where the backup hydraulic source supplies pressure, at which point the backup pressure chamber and the load chamber are connected. The present invention can achieve energy backup for the landing gear retraction and extension system, improving system safety and reliability. Furthermore, through the design of the main valve core and the shuttle valve return spring, the backup energy source cannot be mistakenly switched to a low-pressure state, thereby avoiding the complex system design of energy switching in traditional landing gear retraction and extension systems and greatly reducing the system design weight and maintenance difficulty.

Description

Technical Field

[0001] The present invention belongs to the technical field of aircraft hydraulic valves and relates to a hydraulic valve for a landing gear retraction and extension system, and in particular to a hydraulic energy switching control valve and method for the landing gear retraction and extension system. Background Art

[0002] The landing gear retraction and extension control system is a critical system that affects aircraft takeoff and landing, directly impacting the safety of flight missions. Hydraulic valves are electromechanical devices that utilize electromagnetic or mechanical force to drive the position of a valve core to control the flow of fluid in a pipeline. They are widely used in aircraft landing gear control systems, typically in landing gear control valves and door control valves. Traditional landing gear retraction and extension systems lack the integrated design of hydraulic valves to switch the hydraulic power source within the landing gear retraction and extension control system. This results in a heavier system, complex piping design, high maintenance costs, and a significant risk of leakage.

[0003] For example, CN114180035A describes a hydraulic control valve and control method for a landing gear retraction and extension system. Its emergency release function is a hydraulically driven, non-gear extension control. All load ports are connected to the oil return line, requiring the use of a gravity-controlled landing gear extension system. The door ground maintenance function also relies on the on-off switching of a solenoid valve within the valve block to achieve localized oil flow. The hydraulic energy for all valve block drives derives from a single system. If this hydraulic system fails, the landing gear retraction and extension system loses its hydraulic drive capability.

[0004] Other landing gear hydraulic control valves that use a backup hydraulic system all use multiple valves in a series-parallel design, which takes up a lot of space, makes the system prone to leakage, and is difficult to maintain. Summary of the Invention

[0005] In order to solve the above problems, the present invention provides a hydraulic energy switching control valve and method for a landing gear retraction and extension system. By designing a hydraulic energy switching valve for a landing gear retraction and extension system, energy backup of the landing gear retraction and extension system is achieved, thereby improving system safety and reliability.

[0006] The technical solutions of the present invention are as follows:

[0007] 14. The hydraulic control valve according to claim 13, wherein the control valve has the advantages of being able to control the oil pressure of the control valve and the operating mode of the control valve, and the like. The control valve has the advantages of being able to control the oil pressure of the control valve and the operating mode of the control valve. The control valve has the advantages of being able to control the oil pressure of the control valve and the operating mode of the control valve.

[0008] Furthermore, when the main oil inlet chamber is connected to the main pressure chamber, the main pressure chamber is connected to the load chamber through the shuttle valve, the main oil return chamber is connected to the return oil chamber, the load chamber and the backup pressure chamber are blocked in the oil circuit of the shuttle valve, the backup oil inlet chamber and the backup pressure chamber are blocked in the oil circuit at the valve core, and the backup oil return chamber and the return oil chamber are blocked in the oil circuit at the valve core; when the backup oil inlet chamber is connected to the backup pressure chamber, the backup pressure chamber is connected to the load chamber through the shuttle valve, the backup oil return chamber is connected to the return oil chamber, the load chamber and the main pressure chamber are blocked in the oil circuit of the shuttle valve, the main oil inlet chamber and the main pressure chamber are blocked in the oil circuit at the valve core, and the main oil return chamber and the return oil chamber are blocked in the oil circuit at the valve core.

[0009] Furthermore, a return spring is designed on the left side of the main valve core, and a main valve core guide sleeve is provided on the outside of the main valve core. The main valve core guide sleeve has holes in various cavities in the valve body, and cooperates with the main valve core to realize internal fluid flow direction control.

[0010] Furthermore, a second reset spring, a shuttle valve guide cylinder, a steel ball and a shuttle valve core are provided between the left chamber and the right chamber of the shuttle valve. The shuttle valve guide cylinder, the steel ball and the shuttle valve core can move axially left and right.

[0011] Furthermore, the shuttle valve core, steel ball and shuttle valve guide cylinder are pushed to the right limit position by the pre-tightening force of the reset spring. A conical seal is designed on the right side of the shuttle valve core. When the shuttle valve core moves to the right limit position, it forms a seal with the right structure, isolating the load chamber and the right chamber of the shuttle valve.

[0012] Furthermore, radial hole one and radial hole two are provided between the valve body and the shuttle valve core. Radial hole one connects the main pressure chamber and the load chamber, and radial hole two connects the backup pressure chamber and the load chamber. When the shuttle valve core moves to the left limit position, it blocks the radial hole one, and the steel ball forms a spherical seal with the left structure.

[0013] Furthermore, the valve body is provided with a first nozzle, a second nozzle, a third nozzle, a fourth nozzle, a fifth nozzle and a sixth nozzle, the load chamber is connected with the fifth nozzle, the return oil chamber is connected with the sixth nozzle, the main oil inlet chamber is connected with the first nozzle, the main oil return chamber is connected with the second nozzle, the backup oil inlet chamber is connected with the third nozzle, and the backup oil return chamber is connected with the fourth nozzle; the first nozzle is connected with the main hydraulic source system pressure pipeline, the second nozzle is connected with the main hydraulic source system return oil pipeline, the third nozzle is connected with the backup hydraulic source system pressure pipeline, the fourth nozzle is connected with the backup hydraulic source system return oil pipeline, the fifth nozzle is connected with the landing gear retraction system load pipeline, and the sixth nozzle is connected with the landing gear retraction system return oil pipeline.

[0014] Furthermore, when the pilot solenoid valve is in position 0, the first nozzle and the fifth nozzle are connected, the second nozzle and the sixth nozzle are connected, the third nozzle and the fifth nozzle are blocked, and the fourth nozzle and the sixth nozzle are blocked; when the pilot solenoid valve is in position 1, the first nozzle and the fifth nozzle are blocked, the second nozzle and the sixth nozzle are blocked, the third nozzle and the fifth nozzle are connected, and the fourth nozzle and the sixth nozzle are connected.

[0015] When the control valve is turned on and the pilot solenoid valve is turned on, the control valve is turned off and the control valve is turned off, and the control valve is turned on and the control valve is turned off. When the control valve is turned on, the control valve is turned on and the control valve is turned off, the control valve is turned on and the control valve is turned off. When the control valve is turned on, the control valve is turned on and the control valve is turned off, the control valve is turned on and the control valve is turned off.

[0016] A hydraulic energy switching control method for a landing gear retraction and extension system uses the aforementioned hydraulic energy switching control valve for a landing gear retraction and extension system, and the pilot solenoid valve is energized to work. At this time, the main valve core moves leftward to the limit position along the main valve core guide sleeve under the action of the left pilot solenoid valve; the oil circuit of the main valve core connects the backup oil inlet chamber and the backup pressure chamber, the oil circuit of the main valve core connects the backup oil return chamber and the return oil chamber, and the oil circuit of the main valve core connects the main return oil and the main pressure chamber; the sealing groove of the main valve core blocks the main oil inlet chamber and the main pressure chamber, blocks the main oil return chamber and the return oil chamber, and blocks the backup pressure chamber and the backup oil return chamber; the backup pressure chamber forms hydraulic pressure in the right chamber of the shuttle valve through the flow channel on the upper side of the valve body, pushes the shuttle valve core to slide leftward to the limit position and contacts the left structure to form a seal, cuts off the passage between the main pressure chamber and the load chamber, and connects the backup pressure chamber and the load chamber.

[0017] The beneficial effects of the present invention are as follows:

[0018] 1. The present invention realizes energy backup of the landing gear retraction and extension system by designing a hydraulic energy switching valve for the landing gear retraction and extension system, thereby improving the safety and reliability of the system.

[0019] 2. The shuttle valve of the present invention is integrated to effectively ensure the independence of the main and standby hydraulic energy oils, thereby improving the safety and maintainability of the system.

[0020] 3. The present invention uses the design of the main valve core and the shuttle valve return spring to prevent the backup energy from being switched to a low-pressure state by mistake.

[0021] 4. The present invention avoids the complex system design of energy switching of the traditional landing gear retraction and extension system by realizing the switching capability of the hydraulic energy input end, greatly reduces the system design difficulty and system design weight, and has obvious design advantages. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present invention and should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0023] Figure 1 Schematic diagram of the positions of the nozzles of the valve body of the present invention.

[0024] Figure 2 It is a schematic diagram of the flow path principle between each nozzle in the control valve of the present invention.

[0025] Figure 3 It is a schematic diagram of the control valve structure of the present invention.

[0026] In the figure: 1-valve body, 2-fifth nozzle, 3-sixth nozzle, 4-aviation plug, 5-pilot solenoid valve, 6-fourth nozzle, 7-third nozzle, 8-second nozzle, 9-first nozzle, 10-spring seat one, 11-return spring one, 12-spring seat two, 13-first sealing ring, 14-return spring two, 15-shuttle valve guide cylinder, 16-radial hole one, 17-radial hole two, 18-steel ball, 19-shuttle valve spool, 20-load chamber, 21-main valve spool guide sleeve, 22-main valve spool, 23-second sealing ring, 24-backup oil inlet chamber, 25-backup pressure chamber, 26-backup oil return chamber, 27-oil return chamber, 28-main oil return chamber, 29-main pressure chamber, 30-main oil inlet chamber. DETAILED DESCRIPTION

[0027] This section is an embodiment of the present invention, which is used to explain and illustrate the technical solution of the present invention. In the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

[0028] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate directions or positional relationships for the purposes of the accompanying drawings, and are intended only to facilitate the description of the present invention and simplify the description, rather than to indicate or imply that the device or case referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention. In addition, the terms "first", "second" and the like are used for descriptive purposes only, and should not be understood as indicating or implying relative importance or implying the number of technical features indicated. Thus, features defined as "first", "second" and the like may explicitly or implicitly include more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0029] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be interpreted broadly. For example, they may refer to fixed, detachable, or integrated connections; mechanical or point connections; direct or indirect connections through an intermediary; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0030] Example 1:

[0031] A hydraulic energy switching control valve for a landing gear retraction and extension system includes a valve body 1, a pilot solenoid valve 5 and a shuttle valve. The valve body 1 includes a load chamber 20, a backup oil inlet chamber 24, a backup pressure chamber 25, a backup oil return chamber 26, an oil return chamber 27, a main oil return chamber 28, a main pressure chamber 29 and a main oil inlet chamber 30. The main oil inlet chamber 30 is arranged on the axial left side between the valve body 1 and the main valve core 22, the main pressure chamber 29 is arranged on the axial right side of the main oil inlet chamber 30 and is connected to the left chamber of the shuttle valve, the main oil return chamber 28 is arranged on the axial right side of the main pressure chamber 29, and the oil return chamber 30 is connected to the left chamber of the shuttle valve. The chamber 27 is arranged on the axial right side of the main oil return chamber 28, the backup oil return chamber 26 is arranged on the axial right side of the oil return chamber 27, the backup pressure chamber 25 is arranged on the axial right side of the backup oil return chamber 26 and is connected to the right chamber of the shuttle valve, the backup oil inlet chamber 24 is arranged on the axial right side of the backup pressure chamber 25, and the load chamber 20 is arranged in the middle chamber of the shuttle valve; the pilot solenoid valve 5 is in the 0 position for the main hydraulic source pressure supply state, at which time the main pressure chamber 29 and the load chamber 20 are connected; the pilot solenoid valve 5 is in the 1 position for the backup hydraulic source pressure supply state, at which time the backup pressure chamber 25 and the load chamber 20 are connected.

[0032] When the main oil inlet chamber 30 is connected with the main pressure chamber 29, the main pressure chamber 29 is connected with the load chamber 20 through the shuttle valve, the main oil return chamber 28 is connected with the oil return chamber 27, the load chamber 20 and the backup pressure chamber 25 are blocked in the oil circuit of the shuttle valve, the backup oil inlet chamber 24 and the backup pressure chamber 25 are blocked in the oil circuit at the main valve core 22, and the backup oil return chamber 26 and the oil return chamber 27 are blocked in the oil circuit at the main valve core 22; when the backup oil inlet chamber 24 is connected with the backup pressure chamber 25, the backup pressure chamber 25 is connected with the load chamber 20 through the shuttle valve, the backup oil return chamber 26 is connected with the oil return chamber 27, the load chamber 20 and the main pressure chamber 29 are blocked in the oil circuit of the shuttle valve, the main oil inlet chamber 30 and the main pressure chamber 29 are blocked in the oil circuit at the main valve core 22, and the main oil return chamber 28 and the oil return chamber 27 are blocked in the oil circuit at the main valve core 22.

[0033] A return spring 11 is designed on the left side of the main valve core 22, and a main valve core guide sleeve 21 is provided on the outside of the main valve core 22. The main valve core guide sleeve 21 has holes in each chamber and cooperates with the main valve core 22 to control the flow direction of the internal fluid.

[0034] A return spring 14, a shuttle valve guide cylinder 15, a steel ball 18 and a shuttle valve core 19 are provided between the left and right chambers of the shuttle valve. The shuttle valve guide cylinder 15, the steel ball 18 and the shuttle valve core 19 can move axially left and right.

[0035] The shuttle valve core 19, the steel ball 18 and the shuttle valve guide cylinder 15 are preloaded at the right limit position by the reset spring 2 14. A conical seal is designed on the right side of the shuttle valve core 19. The shuttle valve core 19 moves to the right limit position to form a seal with the right structure, isolating the load chamber 20 and the right chamber of the shuttle valve.

[0036] A radial hole 16 and a radial hole 2 17 are provided between the valve body 1 and the shuttle valve core 19. The radial hole 16 connects the main pressure chamber 29 and the load chamber 20, and the radial hole 27 connects the backup pressure chamber 25 and the load chamber 20. When the shuttle valve core 19 moves to the left limit position, it blocks the radial hole 1, and the steel ball 18 forms a spherical seal with the left structure.

[0037] The valve body 1 is provided with a first nozzle 9, a second nozzle 8, a third nozzle 7, a fourth nozzle 6, a fifth nozzle 2 and a sixth nozzle 3. The load chamber 20 is connected to the fifth nozzle 2, the oil return chamber 27 is connected to the sixth nozzle 3, the main oil inlet chamber 30 is connected to the first nozzle 9, the main oil return chamber 28 is connected to the second nozzle 8, the backup oil inlet chamber 24 is connected to the third nozzle 7, and the backup oil return chamber 26 is connected to the fourth nozzle 6; the first nozzle 9 is connected to the main hydraulic source system pressure line, the second nozzle 8 is connected to the main hydraulic source system oil return line, the third nozzle 7 is connected to the backup hydraulic source system pressure line, the fourth nozzle 6 is connected to the backup hydraulic source system oil return line, the fifth nozzle 2 is connected to the landing gear retraction system load line, and the sixth nozzle 3 is connected to the landing gear retraction system oil return line.

[0038] When the pilot solenoid valve 5 is in position 0, the first nozzle 9 and the fifth nozzle 2 are connected through the flow channel in the valve body, the second nozzle 8 and the sixth nozzle 3 are connected through the flow channel in the valve body, the flow channel between the third nozzle 7 and the fifth nozzle 2 is blocked, and the flow channel between the fourth nozzle 6 and the sixth nozzle 3 is blocked; when the pilot solenoid valve 5 is in position 1, the flow channel between the first nozzle 9 and the fifth nozzle 2 is blocked, the flow channel between the second nozzle 8 and the sixth nozzle 3 is blocked, the third nozzle 7 and the fifth nozzle 2 are connected through the flow channel in the valve body, and the fourth nozzle 6 and the sixth nozzle 3 are connected through the flow channel in the valve body.

[0039] A hydraulic energy switching control method for a landing gear retraction and extension system uses the aforementioned hydraulic energy switching control valve for a landing gear retraction and extension system. The pilot solenoid valve is not energized and is working. At this time, the main valve core moves to the right along the main valve core guide sleeve to the limit position. The oil circuit of the main valve core connects the main oil inlet chamber and the main pressure chamber, the oil circuit of the main valve core connects the main oil return chamber and the oil return chamber, and the oil circuit of the main valve core connects the backup oil return chamber and the backup pressure chamber; the sealing groove of the main valve core blocks the main pressure chamber and the main oil return chamber, blocks the backup pressure chamber and the backup oil inlet chamber, and blocks the backup oil return chamber and the oil return chamber; the main pressure chamber is connected to the load chamber 20 through the shuttle valve on the upper side of the valve body, and the load chamber and the backup pressure chamber are separated by the right side of the shuttle valve core.

[0040] At this time, the backup energy is at low pressure. After the pilot solenoid valve switch is accidentally touched, there is not enough pressure to push the main valve core to move to the left. The backup oil inlet chamber and the backup pressure chamber will not be connected. The main oil inlet chamber and the main pressure chamber will still be connected, and the landing gear will be driven to retract and extend by the main hydraulic energy.

[0041] A hydraulic energy switching control method for a landing gear retraction and extension system uses the aforementioned hydraulic energy switching control valve for a landing gear retraction and extension system, and the pilot solenoid valve is energized to work. At this time, the main valve core moves leftward to the limit position along the main valve core guide sleeve under the action of the left pilot solenoid valve; the oil circuit of the main valve core connects the backup oil inlet chamber and the backup pressure chamber, the oil circuit of the main valve core connects the backup oil return chamber and the return oil chamber, and the oil circuit of the main valve core connects the main return oil and the main pressure chamber; the sealing groove of the main valve core blocks the main oil inlet chamber and the main pressure chamber, blocks the main oil return chamber and the return oil chamber, and blocks the backup pressure chamber and the backup oil return chamber; the backup pressure chamber forms hydraulic pressure in the right chamber of the shuttle valve through the flow channel on the upper side of the valve body, pushes the shuttle valve core to slide leftward to the limit position and contacts the left structure to form a seal, cuts off the passage between the main pressure chamber and the load chamber, and connects the backup pressure chamber and the load chamber.

[0042] Example 2:

[0043] A hydraulic energy switching control valve for a landing gear retraction and extension system comprises an electromagnetic pilot valve, a shuttle valve and a valve body of the control valve.

[0044] like Figure 1As shown, the control valve is a two-position six-way structure, and the valve body 1 of the control valve is equipped with a first nozzle 9, a second nozzle 8, a third nozzle 7, a fourth nozzle 6, a fifth nozzle 2, a sixth nozzle 3 and an air plug 4.

[0045] The first nozzle 9 of the valve body 1 is connected to the pressure line of the main hydraulic source system.

[0046] The second nozzle 8 of the valve body 1 is connected to the oil return line of the main hydraulic source system.

[0047] The third nozzle 7 of the valve body 1 is connected to the pressure pipeline of the backup hydraulic source system.

[0048] The fourth nozzle 6 of the valve body 1 is connected to the oil return line of the backup hydraulic source system.

[0049] The fifth nozzle 2 of the valve body 1 is connected to the load pipeline of the landing gear retraction and extension system.

[0050] The sixth nozzle 3 of the valve body 1 is connected to the oil return line of the landing gear retraction and extension system.

[0051] like Figure 3 As shown, a main valve core 22 is designed in the valve body 1, a shuttle valve is designed on the upper side, and a pilot solenoid valve 5 is designed on the right side.

[0052] The valve body 1 includes a main valve core 22, a main valve core guide sleeve 21, a return spring 11 and a spring seat 10.

[0053] The valve body 1 is provided with a main oil inlet chamber 30 , a main pressure chamber 29 , a main oil return chamber 28 , a backup oil inlet chamber 24 , a backup pressure chamber 25 , a backup oil return chamber 26 , a load chamber 20 , and an oil return chamber 27 .

[0054] The main valve core guide sleeve 21 has openings at the chamber of the valve body 1 for cooperating with the main valve core 22 to realize internal fluid flow control.

[0055] The main valve core 22 is provided with an oil passage groove between adjacent holes of the main valve core guide sleeve 21, which can be used to communicate between two adjacent chambers.

[0056] The main valve core 22 is provided with a sealing groove between the oil passage grooves, which can be used to seal two adjacent chambers.

[0057] The valve body 1 is provided with a passage connecting the main pressure chamber 29 and the left chamber of the shuttle valve, and the valve body 1 is provided with a passage connecting the backup pressure chamber 25 and the right chamber of the shuttle valve.

[0058] Between the left and right chambers of the shuttle valve are located a return spring 14, a shuttle valve guide cylinder 15, a steel ball 18, and a shuttle valve core 19. The shuttle valve guide cylinder 15, steel ball 18, and shuttle valve core 19 are integrated into a single unit and can move left or right. The assembly is as follows: a return spring 14 is mounted on the outer surface of the shuttle valve guide cylinder 15, the right end of the shuttle valve guide cylinder 15 is connected to the steel ball 18, and the shuttle valve core 19 is mounted circumferentially to the right of the steel ball 18.

[0059] The shuttle valve core 19, steel ball 18, and shuttle valve guide cylinder 15 are preloaded to the right limit position by the preload force of return spring 2 14. A tapered surface is designed on the right side of the shuttle valve core 19. When the shuttle valve core 19 moves right to its limit position, it forms a seal with the right side structure, namely, the hole structure in the right chamber. The rear end of the hole structure in the right chamber is connected to the backup pressure chamber 25.

[0060] A radial hole 16 and a radial hole 2 17 are designed between the shuttle valve shell structure and the shuttle valve spool 19. The radial hole 16 is used to connect the main pressure chamber 29 with the load chamber 20 of the landing gear retraction and extension system, and the radial hole 2 is used to connect the backup pressure chamber 25 with the load chamber 20 of the landing gear retraction and extension system.

[0061] When the shuttle valve core 19 moves to the left limit position, it can block the radial hole 16, and the left end of the steel ball 18 can form a sealing fit with the left side structure of the inner wall of the shuttle valve housing.

[0062] See also Figures 1 to 3 The load chamber 20 is connected to the fifth nozzle 2, the oil return chamber 27 is connected to the sixth nozzle 3, the main oil inlet chamber 30 is connected to the first nozzle 9, the main oil return chamber 28 is connected to the second nozzle 8, the backup oil inlet chamber 24 is connected to the third nozzle 7, and the backup oil return chamber 26 is connected to the fourth nozzle 6.

[0063] The main oil inlet chamber 30 is connected to the main pressure chamber 29, and the main pressure chamber 29 is connected to the load chamber 20 through the shuttle valve core 19 and the radial hole 16.

[0064] The main oil return chamber 28 is connected to the oil return chamber 27 through the main valve core guide sleeve 21.

[0065] The load chamber 20 and the backup pressure chamber 25 are blocked at the shuttle valve core 19, the backup oil inlet chamber 24 and the backup pressure chamber 25 are blocked at the main valve core 22, and the backup oil return chamber 26 and the oil return chamber 27 are blocked at the main valve core 22.

[0066] The shuttle valve core 19 and the steel ball 18 are kept in the right limit position under the action of the left return spring 2 14 . The return spring 2 14 is installed on the spring seat 2 12 . A shuttle valve guide cylinder 15 is designed on the right side of the return spring 2 14 .

[0067] See also Figure 2 The pilot solenoid valve 5 is in the main hydraulic source pressure supply state at position 0, the first nozzle 9 and the fifth nozzle 2 are connected through the valve internal flow channel, the second nozzle 8 and the sixth nozzle 3 are connected, the third nozzle 7 and the fifth nozzle 2 flow channels are blocked, and the fourth nozzle 6 and the sixth nozzle 3 flow channels are blocked.

[0068] The pilot solenoid valve 5 is in the backup hydraulic source pressure supply state in position 1, the first nozzle 9 and the fifth nozzle 2 are blocked by the valve flow channel, the second nozzle 8 and the sixth nozzle 3 are blocked, the third nozzle 7 and the fifth nozzle 2 are connected through the flow channel, and the fourth nozzle 6 and the sixth nozzle 3 are connected through the flow channel.

[0069] See also Figure 3 When the pilot solenoid valve 5 is de-energized, the main valve core 22 moves rightward to its limit position along the main valve core guide sleeve 21 under the action of the left return spring 11. The main valve core 22's oil circuit connects the main oil inlet chamber 30 with the main pressure chamber 29, the main oil return chamber 28 with the oil return chamber 27, and the backup oil return chamber 26 with the backup pressure chamber 25. The main valve core 22 is designed with multiple sealing grooves to seal the main pressure chamber 29 from the main oil return chamber 28, the backup pressure chamber 25 from the backup oil inlet chamber 24, and the backup oil return chamber 26 from the oil return chamber 27. The main pressure chamber 29 is connected to the load chamber 20 via the shuttle valve guide cylinder 15 on the upper side of the valve body and through the radial hole 16. The load chamber 20 and the backup pressure chamber 25 are separated by a cone seal on the right side of the shuttle valve core 19.

[0070] When the pilot solenoid valve 5 is energized, the main valve core 22, under the action of the left pilot solenoid valve 5, moves leftward along the main valve core guide sleeve 21 to the limit position, contacting the spring seat 10. The oil circuit designed for the main valve core 22 connects the backup oil inlet chamber 24 with the backup pressure chamber 25. The oil circuit designed for the main valve core 22 connects the backup oil return chamber 26 with the oil return chamber 27. The oil circuit designed for the main valve core 22 connects the main oil return chamber 28 with the main pressure chamber 29. The main valve core 22 is designed with multiple sealing grooves to seal the main oil inlet chamber 30 from the main pressure chamber 29, the main oil return chamber 28 from the oil return chamber 27, and the backup pressure chamber 25 from the backup oil return chamber 26. The backup pressure chamber 25 forms hydraulic pressure on the right side of the shuttle valve core 19 through the flow channel on the upper side of the valve body, pushing the shuttle valve core 19 and the steel ball 18 to slide left to the limit position. The steel ball 18 contacts the left side structure to form a seal. The shuttle valve core 19 moves left to the limit position, blocking the radial hole 16, cutting off the passage between the main pressure chamber 29 and the load chamber 20, and the backup pressure chamber 25 is connected to the load chamber 20 through the radial hole 2 17.

[0071] The present invention includes the hydraulic energy switching function of the landing gear retraction and extension system, the backup energy failure mis-switching protection function, and the function of preventing the main and backup hydraulic energy oils from mixing. The specific working principle is as follows:

[0072] a. Hydraulic energy switching: When the pilot solenoid valve is energized, the main valve core moves left to the limit position, and the backup hydraulic energy oil enters the right side of the shuttle valve, pushing the shuttle valve and the steel ball to the left, blocking the radial hole 1, cutting off the flow path between the main pressure chamber and the load chamber, and at the same time connecting the backup pressure chamber and the load chamber through the radial hole 2.

[0073] b. Protection against mis-switching due to backup energy failure: When the backup energy is under low pressure and the pilot solenoid valve switch is mistakenly touched, after the pilot solenoid valve is turned on, based on the above-mentioned design features, there is not enough pressure to push the main valve core to the left, and the backup oil inlet chamber and the backup pressure chamber will not be connected. The main oil inlet chamber and the main pressure chamber will still be connected, and the landing gear will be driven to retract or extend by the main hydraulic energy.

[0074] c. When the pilot solenoid valve is not energized, the shuttle valve core moves to the right limit position to block the radial hole 2, and the return spring 2 pushes the shuttle valve core to the right limit position, using the cone seal on the right side of the shuttle valve core to avoid cross-contamination between the main and backup energy sources.

[0075] d When the pilot solenoid valve is energized, the shuttle valve core moves left to the limit position to block radial hole 1, and the steel ball blocks the left oil circuit to prevent the main and standby energy oils from mixing with each other.

[0076] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can utilize the above-disclosed technical content to make many possible variations and modifications to the technical solution of the present invention, or modify it into equivalent embodiments with equivalent variations, without departing from the scope of the technical solution of the present invention. Therefore, any simple modifications, equivalent variations, and modifications made to the above embodiments in accordance with the technical essence of the present invention that do not depart from the content of the technical solution of the present invention shall fall within the scope of protection of the technical solution of the present invention.

Claims

1. A hydraulic energy switching control valve for a landing gear retraction and extension system, characterized in that: The invention comprises a valve body (1), a pilot solenoid valve (5) and a shuttle valve. The valve body (1) comprises a load chamber (20), a backup oil inlet chamber (24), a backup pressure chamber (25), a backup oil return chamber (26), an oil return chamber (27), a main oil return chamber (28), a main pressure chamber (29) and a main oil inlet chamber (30). The main oil inlet chamber (30) is arranged on the left side of the axial direction between the valve body (1) and the main valve core (22), and the main pressure chamber (29) is arranged on the axial direction of the main oil inlet chamber (30). To the right and connected to the left chamber of the shuttle valve, the main oil return chamber (28) is located on the axial right side of the main pressure chamber (29), the oil return chamber (27) is located on the axial right side of the main oil return chamber (28), the backup oil return chamber (26) is located on the axial right side of the oil return chamber (27), the backup pressure chamber (25) is located on the axial right side of the backup oil return chamber (26) and connected to the right chamber of the shuttle valve, the backup oil inlet chamber (24) is located on the axial right side of the backup pressure chamber (25), and the load chamber (20) is located in the middle chamber of the shuttle valve; The pilot solenoid valve (5) is in the main hydraulic source pressure supply state at position 0, at which time the main pressure chamber (29) and the load chamber (20) are connected; the pilot solenoid valve (5) is in the backup hydraulic source pressure supply state at position 1, at which time the backup pressure chamber (25) and the load chamber (20) are connected; a return spring 2 (14), a shuttle valve guide cylinder (15), a steel ball (18) and a shuttle valve core (19) are provided between the left chamber and the right chamber of the shuttle valve, and the shuttle valve guide cylinder (15), the steel ball (18) and the shuttle valve core (19) are provided. The valve core (19) can move axially left and right; radial hole one (16) and radial hole two (17) are provided between the valve body (1) and the shuttle valve core (19); radial hole one (16) communicates with the main pressure chamber (29) and the load chamber (20), and radial hole two (17) communicates with the backup pressure chamber (25) and the load chamber (20); when the shuttle valve core (19) moves to the left limit position, it blocks the radial hole one (16), and the steel ball (18) forms a spherical seal with the left structure.

2. The hydraulic energy switching control valve of the landing gear retraction and extension system according to claim 1, characterized in that: When the main oil inlet chamber (30) is connected to the main pressure chamber (29), the main pressure chamber (29) is connected to the load chamber (20) through the shuttle valve, the main oil return chamber (28) is connected to the oil return chamber (27), the load chamber (20) and the backup pressure chamber (25) are blocked in the oil path of the shuttle valve, the backup oil inlet chamber (24) and the backup pressure chamber (25) are blocked in the oil path at the main valve core (22), and the backup oil return chamber (26) and the oil return chamber (27) are blocked in the oil path at the main valve core (22); When the backup oil inlet chamber (24) is connected to the backup pressure chamber (25), the backup pressure chamber (25) is connected to the load chamber (20) through the shuttle valve, the backup oil return chamber (26) is connected to the oil return chamber (27), the load chamber (20) and the main pressure chamber (29) are blocked in the oil path of the shuttle valve, the main oil inlet chamber (30) and the main pressure chamber (29) are blocked in the oil path at the main valve core (22), and the main oil return chamber (28) and the oil return chamber (27) are blocked in the oil path at the main valve core (22).

3. The hydraulic energy switching control valve of a landing gear retraction and extension system according to claim 1, characterized in that: A return spring (11) is designed on the left side of the main valve core (22), and a main valve core guide sleeve (21) is provided on the outside of the main valve core (22). The main valve core guide sleeve (21) has holes at various cavities in the valve body (1) and cooperates with the main valve core (22) to realize internal fluid flow direction control.

4. The hydraulic energy switching control valve of a landing gear retraction and extension system according to claim 1, characterized in that: The shuttle valve core (19), the steel ball (18) and the shuttle valve guide cylinder (15) are preloaded at the right limit position by the second return spring (14). The right side of the shuttle valve core (19) is designed with a conical seal. When the shuttle valve core (19) moves right to the limit position, it forms a seal with the right side structure, isolating the load chamber (20) and the right chamber of the shuttle valve.

5. The hydraulic energy switching control valve of a landing gear retraction and extension system according to claim 1, characterized in that: The valve body (1) is provided with a first nozzle (9), a second nozzle (8), a third nozzle (7), a fourth nozzle (6), a fifth nozzle (2) and a sixth nozzle (3); the load chamber (20) is communicated with the fifth nozzle (2), the oil return chamber (27) is communicated with the sixth nozzle (3), the main oil inlet chamber (30) is communicated with the first nozzle (9), the main oil return chamber (28) is communicated with the second nozzle (8), the backup oil inlet chamber (24) is communicated with the third nozzle (7), and the backup oil return chamber (26) is communicated with the fourth nozzle (6); the first nozzle (9) is communicated with the main hydraulic source system pressure pipeline, the second nozzle (8) is connected with the main hydraulic source system oil return pipeline, the third nozzle (7) is connected with the backup hydraulic source system pressure pipeline, the fourth nozzle (6) is connected with the backup hydraulic source system oil return pipeline, the fifth nozzle (2) is connected with the landing gear retraction system load pipeline, and the sixth nozzle (3) is connected with the landing gear retraction system oil return pipeline.

6. The hydraulic energy switching control valve of the landing gear retraction and extension system according to claim 5, characterized in that: When the pilot solenoid valve (5) is in position 0, the first nozzle (9) and the fifth nozzle (2) are connected, the second nozzle (8) and the sixth nozzle (3) are connected, the third nozzle (7) and the fifth nozzle (2) are blocked, and the fourth nozzle (6) and the sixth nozzle (3) are blocked; when the pilot solenoid valve (5) is in position 1, the first nozzle (9) and the fifth nozzle (2) are blocked, the second nozzle (8) and the sixth nozzle (3) are blocked, the third nozzle (7) and the fifth nozzle (2) are connected, and the fourth nozzle (6) and the sixth nozzle (3) are connected.

7. A method for controlling hydraulic energy switching of a landing gear retraction system, using the hydraulic energy switching control valve of a landing gear retraction system according to claim 3, characterized in that: When the pilot solenoid valve is not energized, the main valve core moves to the right to the limit position along the main valve core guide sleeve, and the oil circuit of the main valve core connects the main oil inlet chamber and the main pressure chamber, the oil circuit of the main valve core connects the main oil return chamber and the oil return chamber, and the oil circuit of the main valve core connects the backup oil return chamber and the backup pressure chamber; the sealing groove of the main valve core blocks the main pressure chamber and the main oil return chamber, blocks the backup pressure chamber and the backup oil inlet chamber, and blocks the backup oil return chamber and the oil return chamber; the main pressure chamber is connected to the load chamber through the shuttle valve on the upper side of the valve body, and the load chamber and the backup pressure chamber are separated by the right side of the shuttle valve core; At this time, the backup energy is at low pressure. After the pilot solenoid valve switch is accidentally touched, there is not enough pressure to push the main valve core to move to the left. The backup oil inlet chamber and the backup pressure chamber will not be connected. The main oil inlet chamber and the main pressure chamber will still be connected, and the landing gear will be driven to retract and extend by the main hydraulic energy.

8. A method for controlling hydraulic energy switching of a landing gear retraction system, using the hydraulic energy switching control valve of a landing gear retraction system according to claim 3, characterized in that: When the pilot solenoid valve is energized and operates, the main valve core moves to the left to the limit position along the main valve core guide sleeve under the action of the left pilot solenoid valve; the oil circuit of the main valve core connects the backup oil inlet chamber and the backup pressure chamber, the oil circuit of the main valve core connects the backup oil return chamber and the oil return chamber, and the oil circuit of the main valve core connects the main return oil and the main pressure chamber; the sealing groove of the main valve core blocks the main oil inlet chamber and the main pressure chamber, blocks the main oil return chamber and the oil return chamber, and blocks the backup pressure chamber and the backup oil return chamber; The backup pressure chamber forms hydraulic pressure in the right chamber of the shuttle valve through the flow channel on the upper side of the valve body, so that the shuttle valve connects the right chamber and the load chamber, cuts off the passage between the main pressure chamber and the load chamber, and the backup pressure chamber is connected to the load chamber.

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