Landing gear door upper lock control logic coordination valve

Abstract

A landing gear door upper lock control logic coordination valve disclosed by the present invention has a wide coordination range and higher reliability. The present invention is realized through the following technical solutions: The inlet nozzle supplies pressure. The upper lock drives the pressure rod through a pressing mechanism, compresses the valve core return spring through a stepped shaft, drives the valve seat to seal the valve core, and closes the nozzle. When the upper lock of the door is fully opened, the upper lock applies a pressing force to the pressure rod through the movement track of the pressing mechanism. The pressure rod pushes the valve core, compresses the valve core return spring, separates the valve seat of the valve, triggers the valve holes distributed on the conical shell of the valve core, and the hydraulic oil enters the valve cavity of the rear end cover through the pressure supply oil circuit of the door actuator cylinder, flows out from the outlet nozzle to the door actuator cylinder, and pushes the actuator cylinder to open the door. Under the action of the elastic force of the compressed valve core return spring and the valve core return spring, the pressure rod is pressed at the initial position, realizing simultaneous pressure supply of the upper lock and the door actuator cylinder, and completing the control logic of the sequential movement order through the trigger type coordination valve.

Description

Technical Field

[0001] The present invention relates to an upper lock trigger type coordination valve for a landing gear door that can simplify control logic. Background Art

[0002] The landing gear retraction and extension system is mainly used to control the retraction and extension of the landing gear, and to control the opening and closing of the main landing gear doors, the nose landing gear doors and the landing gear. It is an important system of the aircraft, and its normal operation will directly affect flight safety. Each landing gear bay has a hydraulic actuator for the door, namely the forward nose landing gear door and the inner main landing gear door. Since the main hydraulic control and actuator components of the landing gear control system are installed in the landing gear bay, these components include safety isolation valves, landing gear and door selector valves, bypass valves, upper locks and door actuators, etc. Therefore, in order to facilitate the maintenance and servicing of these components, each landing gear door has a set of ground door opening mechanisms. The bypass valve is installed on the closing pipeline of the door actuator. During normal retraction and extension, the hydraulic oil directly passes through the bypass valve. When operating the ground door opening mechanism to open the door, the ground door opening handle will pull the push-pull cable, and the push-pull cable will then pull the control rod to rotate the spline shaft. The spline shaft drives the driving wheel coaxial with it, and the spool valve moves to the left under the drive of the driving wheel, thus achieving the closing (disconnection) of the hydraulic supply and connecting the two chambers of each door actuator. At the same time, the hydraulic lock effect can be prevented, and the door opens under the action of gravity. The working principle of the door upper lock release mechanism and the upper lock emergency release mechanism is the same, and they share a release rod. The difference lies in the use of different spline shafts respectively arranged on both sides of the upper lock; under the action of high-pressure oil, the piston rod of the lower lock actuator cylinder retracts, and the lower lock opens. Another way of high-pressure oil, on the one hand, opens the hydraulic control check valve to communicate the return oil of the door actuator cylinder; on the other hand, the oil enters the retraction and extension actuator cylinder through the flow-limiting valve, causing the piston rod to extend, the landing gear to retract, and the return oil of the actuator cylinder to flow into the tank through the valve, the emergency conversion valve, the electro-hydraulic directional valve and the emergency drain valve. When the landing gear is retracted, the coordination valve is pressed through, and high-pressure oil enters the retraction chamber of the door actuator cylinder to retract the door. The valve core of the valve presses through the oil circuit from the B chamber (rear coordination valve chamber) to the A chamber (front coordination valve chamber) of the temporarily interrupted coordination valve, and flows into the retraction chamber (rodless chamber) of the retraction and extension actuator cylinder through the speed control valve to complete the product retraction action. At this time, the upper lock chamber (rodless chamber) of the lower lock actuator cylinder and the extension chamber (return oil of the rod chamber) of the retraction and extension actuator cylinder, the return oil of the upper lock chamber of the lower lock actuator cylinder passes through the throttle valve, flows through the coordination valve and then the return oil of the extension chamber of the retraction and extension actuator flows through the speed control valve and then converges into an oil circuit and flows back to the tank. When the retraction and extension actuator cylinder lowers the product (the piston rod retracts), the piston rod retraction action is very slow, and the return oil is blocked with too much pressure. After repeatedly checking the return oil pipeline and adjusting the throttle valve in the return oil pipeline, the damping of the actuator cylinder, etc., no effect is seen. After analysis, it is related to the failure of the connected coordination valve. When the retraction and extension actuator cylinder of the coordination valve structure circle lowers the product. The hydraulic oil coming out of the solenoid valve is first divided into two paths. One path flows into the upper lock actuator cylinder to open the upper lock first. The other path is further divided into two paths. One path flows through the coordination valve 2. Since the B chamber to A chamber of the coordination valve 2 is temporarily blocked, this oil path is temporarily interrupted.One way of the oil flows through the speed control valve and into the lower chamber (rod chamber) of the retraction and extension actuator to lower the product. After the product is lowered in place, it will press through the B chamber to the A chamber of the coordination valve 2, allowing the temporarily interrupted oil path to flow through the coordination valve 2 and into the upper locking chamber (rodless chamber) of the lower position lock actuator, completing the product lowering and locking actions. At this time, the oil return from the retraction chamber (rodless chamber) of the retraction and extension actuator passes through the speed control valve and the coordination valve 1, and opens the lower position lock actuator. When retracting the product with the retraction and extension actuator, the hydraulic oil from the solenoid valve is divided into two paths. One path flows into the coordination valve 1, and the B chamber to the A chamber of the coordination valve 1 is temporarily blocked. This oil path is temporarily interrupted. The other path of oil flows through the throttle valve and into the unlocking chamber (rod chamber) of the lower position lock actuator to unlock it. After unlocking, the ejector rod of the unlocking actuator will push and press. When the landing gear retraction and extension handle in the cockpit is placed in the "retract" position, the hydraulic solenoid valve is turned on, and the piston rod of the main strut fairing actuator retracts to place the strut fairing in the "retract" position. After the main strut fairing is retracted in place, the landing gear retraction and extension hydraulic solenoid valve is turned on, connecting the "retract" pipeline of the landing gear hydraulic system to the pressure pipeline, and the "lower" pipeline to the oil return pipeline. The pressure oil flows through the throttle valve to the nose landing gear hydraulic lock and the anti-skid actuator to brake the wheels. At the same time, the pressure oil flows to the main landing gear hydraulic lock, the upper position lock unlocking actuator, and the coordination valve, causing the upper position lock unlocking actuator to retract. When the strut is hooked on the lock, the upper position lock closes. Due to the structural limitation of the coordination valve, the oil fluid cannot pass through the coordination valve to reach the wheel fairing actuator. Only when the oil fluid from the hydraulic lock enters the retraction chamber of the landing gear retraction and extension actuator and the retraction action of the landing gear is completed, the main landing gear strut presses the ejector rod of the coordination valve. After the ejector rod pushes open the steel ball, the oil fluid passes through the coordination valve and flows into the retraction chamber of the main landing gear fairing retraction and extension actuator to retract the fairing. When the hydraulic retraction and extension actuator retracts, the oil return resistance is relatively large, and the retraction speed is too slow. To ensure the reliable opening of the aircraft cabin door, the aircraft hydraulic system generally supplies pressure to the upper position lock of the cabin door first. When the upper position lock of the cabin door is fully unlocked, it then supplies pressure to the cabin door actuator to open the cabin door.

[0003] One end of the main landing gear door is installed on the airframe structure. The upper door lock is fixed on the upper lock bracket. When the door is closed, the upper lock hooks the door lock ring. The retraction and extension of the landing gear door are achieved by means of electric control and hydraulic drive: when receiving the control command for lowering the landing gear, the landing gear control valve opens, and the hydraulic drive actuates the upper lock actuator to unlock, the upper lock hook is lowered, and the door is opened to the lowered position under the drive of the actuator. When the main landing gear door is retracted, the door is closed under the drive of the actuator. At the end moment, the lock hook is driven to rotate by the door lock ring to achieve locking. When the landing gear is retracted, the coordination valve is pressed through, and high-pressure oil enters the retraction chamber of the door actuator to retract the door. Thus, it can be seen that the opening or closing of the landing gear door is closely related to the retraction and extension of the landing gear. Due to the large number of moving mechanisms, there are usually multiple driving forces coordinated in the system. When the aircraft takes off and lands, the landing gear door and the landing gear act according to a certain motion sequence to achieve the opening, lowering of the door and the retraction and extension of the landing gear. Due to the coordinated movement of multiple mechanisms, when controlling the retraction and extension of the landing gear door, the phenomenon that may occur is that the upper lock of the landing gear door cannot be locked and the door cannot be closed. Usually, the retraction and extension of the landing gear and the door are controlled by a coordination valve and a solenoid valve, which can lower the door first and then lower the landing gear when lowering the landing gear. The coordination valve functions as a sequence valve here. Therefore, the trigger-type coordination valve of the upper lock of the landing gear door is the key technology in the coordinated installation process of the door. Due to the relatively complex pressure supply control logic on the aircraft and the existence of a sequential movement order between the door and the upper lock, if the retraction and extension time of the landing gear is not coordinated or there is a left-right imbalance, it will cause abnormalities in the main landing gear door. There are two possible reasons for the abnormal retraction of the main landing gear door: 1) The coordination valve is not sealed, causing the retraction pipeline of the main landing gear door actuator to be filled with oil in advance, making the ball lock unlock. Thus, under the action of the oil return pressure, the main landing gear door is abnormally retracted. 2) The check valve installed on the oil return pipeline of the coordination valve is not sealed (it cannot play a one-way role). When the coordination valve is not pressed, the oil leakage pipeline of the coordination valve communicates with the retraction pipeline of the main landing gear door actuator in the oil return pipeline of the landing gear retraction and extension system. After the landing gear handle is pulled back from the "retract" position to the "neutral" position, the "retract" and "lower" oil circuits of the landing gear are both connected to the oil return circuit. When the landing gear drops, the oil return pressure is high, causing the ball lock of the main landing gear door actuator to unlock abnormally. Summary of the Invention

[0004] The task of the present invention is to aim at the sequential movement order between the door and the upper lock and the relatively complex pressure supply control logic on the aircraft. To simplify the aircraft pressure supply control logic or reduce the use of sequence valves, and enable the doors on the aircraft to have a sequential movement order, it is intended to provide a trigger-type coordination valve for the upper lock of the landing gear door with a wider coordination range and higher reliability, especially an upper lock trigger-type coordination valve installed on the upper lock of the landing gear door that can complete the sequential movement order.

[0005] The technical solution adopted by the present invention to solve its technical problems is as follows: A landing gear door upper lock control logic coordination valve, comprising: a coordination valve housing integrating an installation interface for installing an upper lock and having an oil inlet nozzle 1 radially communicating with a front coordination valve cavity, a valve seat 6 and a valve core 8 assembled in the front coordination valve cavity, a push rod 3 sleeved with a push rod return spring 5, and an end cover 10 having an oil outlet nozzle, characterized in that: the push rod 3 sequentially passes through a dust-proof ring 4 and a sealing ring 2, passes through the spring seat plate of the valve seat 6, and is assembled on a bearing; under the action of a pressing mechanism 16, the push rod 3 uses the acting force of the movement track 17 of the pressing mechanism, the upper lock drives the push rod 3 through the pressing mechanism, the oil inlet nozzle 1 supplies pressure, the push rod 3 compresses the push rod return spring 5 through a stepped shaft, drives the valve seat 6 to seal the valve core 8, and controls the outflow of hydraulic oil from the oil outlet nozzle; when the upper lock of the cabin door is fully opened, the upper lock applies a pressing force to the push rod 3 through the movement track of the pressing mechanism, the push rod 3 pushes the valve core 8, compresses the valve core return spring 9, separates the valve seat 6, triggers the valve holes distributed on the conical shell of the valve core 8, the hydraulic oil enters the rear end cover valve cavity through the pressure supply oil circuit of the cabin door actuator, flows from the oil outlet nozzle to the cabin door actuator, pushes the cabin door actuator to open the cabin door, compresses the valve core return spring 9 and the push rod return spring 5, and under the action of the elastic force, presses the push rod 3 to the initial position, realizing the simultaneous pressure supply of the upper lock and the cabin door actuator, and completing the control logic of the sequential movement sequence through the trigger type coordination valve.

[0006] The present invention has the following beneficial effects compared with the prior art: The present invention adopts a coordination valve housing integrating an installation interface for installing an upper lock and having an oil inlet nozzle 1 radially communicating with a front coordination valve cavity, a valve seat 6, a valve core 8, a push rod 3 sleeved with a push rod return spring 5 and a rear end cover valve cavity assembled in the front coordination valve cavity. Compared with the traditional valve control, the coordination valve is small in size and light in weight, and can be integrated with other hydraulic products. Taking the upper lock and the cabin door as an example, when the trigger valve is integrated with the upper lock, the control logic of simultaneous pressure supply of the upper lock and the cabin door actuator can be realized, simplifying the hydraulic control of the upper lock of the landing gear door on the aircraft while reducing the weight and space volume.

[0007] In the present invention, the upper lock applies a pressing force to the pressure rod 3 through the movement track of the pressing mechanism. The pressure rod 3 pushes the valve core 8, compresses the valve core return spring 9, separates the valve seat 6 of the valve, triggers the valve oil holes distributed on the conical shell of the valve core 8, and the hydraulic oil enters the valve cavity of the rear end cover through the pressure supply oil circuit of the hatch actuator cylinder, flows from the oil outlet nozzle to the hatch actuator cylinder, and pushes the actuator cylinder to open the hatch. Under the action of the elastic force of the compressed valve core return spring 9 and the pressure rod return spring 5, the pressure rod 3 is pressed at the initial position. While realizing simultaneous pressure supply for the upper lock and the hatch actuator cylinder, the control logic of the sequential movement order is completed through the trigger - type coordination valve installed on the upper lock of the landing gear hatch. Using this trigger - type coordination valve simplifies the aircraft hydraulic control logic. This mechanical structure on the upper lock triggers the coordination valve, and the trigger - type coordination valve completes the sequential movement order. It has a wide coordination range, simplifies the aircraft pressure supply control logic or reduces the use of sequence valves, and realizes simultaneous hydraulic pressure supply for the sequential actions of the upper lock of the landing gear hatch. It has higher reliability than traditional valve - type control. Brief Description of the Drawings

[0008] Figure 1 is a cross - sectional view of the structure of the trigger - type coordination valve of the upper lock of the landing gear hatch of the present invention.

[0009] Figure 2 is Figure 1 a schematic diagram of the trigger working state of

[0010] Figure 3 is Figure 1 a three - dimensional schematic diagram of

[0011] In the figure: 1 oil inlet nozzle, 2 sealing ring, 3 pressure rod, 4 dust - proof ring, 5 pressure rod return spring, 6 valve seat of the valve, 7 sealing ring, 8 valve core, 7 protective ring, 9 valve core return spring, end cover 10, 11 oil outlet nozzle, 12 coordination valve housing, 13 front coordination valve cavity nozzle, 14 rear end - cover valve cavity, 15 valve oil hole, 16 pressing mechanism, 17 movement track of the pressing mechanism.

[0012] The present invention will be further described below in conjunction with the drawings and embodiments, but the present invention is not limited to the scope of the described embodiments. All these concepts should be regarded as the disclosed content of the present technology and the protection scope of the present invention. Detailed Embodiment

[0013] Refer to Figures 1 to 3In the preferred embodiment described below, a landing gear door upper lock trigger type coordination valve comprises: a coordination valve housing integrated with a mounting interface for mounting an upper lock and provided with an oil inlet nozzle 1 radially connected to a front coordination valve cavity, a valve seat 6 and a valve core 8 assembled in the front coordination valve cavity, a pressure rod 3 equipped with a pressure rod return spring 5, and an end cover 10 provided with an oil outlet nozzle, wherein: a sealing groove for assembling a sealing ring 7 is formed on the outside of the valve seat 6, the end cover 10 is connected to the valve seat 6 through a sealing ring, and a sealing ring 7 is provided on the outer circle of the opening end.

[0014] The pressure rod 3 passes through the dust ring 4 and the sealing ring 2 in sequence, passes through the spring seat plate of the valve seat 6, and is assembled on the bearing; under the action of the pressing mechanism 16, the pressure rod 3 uses the force of the pressing mechanism motion trajectory 17, and the upper lock links the pressure rod 3 through the pressing mechanism, and the oil inlet nozzle 1 supplies pressure. The pressure rod 3 compresses the pressure rod return spring 5 through the stepped shaft, drives the valve seat 6 to seal the valve core 8, and controls the outflow of hydraulic oil from the oil outlet nozzle; when the hatch door upper lock is fully opened, the upper lock applies pressing force to the pressure rod 3 through the pressing mechanism motion trajectory, and the pressure rod 3 pushes the valve core 8, compresses the valve core return spring 9, separates the valve seat 6, triggers the valve oil holes distributed on the conical shell of the valve core 8, and the hydraulic oil enters the valve cavity of the rear end cover through the pressure supply oil circuit of the door actuator, flows from the oil outlet nozzle to the door actuator, pushes the door actuator to open the door, compresses the valve core return spring 9 and the pressure rod return spring 5, and presses the pressure rod 3 to the initial position under the action of elastic force, so as to realize the simultaneous pressure supply of the upper lock and the door actuator, and complete the control logic of the sequence of movement through the trigger-type coordination valve.

[0015] When the oil inlet nozzle 1 is not pressurized, the valve core reset spring 9 presses the valve core 8 and the valve seat 6 to prevent the valve seat and the valve core from being separated due to vibration and impact on the aircraft, and the pressure rod reset spring 5 presses the pressure rod to the initial position. When the oil inlet nozzle 1 is pressurized, the oil cannot flow out of the oil outlet nozzle due to the sealing effect of the valve seat and the valve core; when the upper lock of the cabin door is fully opened, the mechanical structure of the upper lock presses the pressure rod 3, and the pressure rod 3 pushes the valve core 8 to separate from the valve seat 6. At this time, the oil in the oil inlet nozzle 1 can flow to the cabin door actuator through the oil outlet nozzle, and the cabin door actuator opens the cabin door.

[0016] The scope of the present invention is not limited to the specific technical solutions described. Various modifications to the above-mentioned embodiments will be obvious to those skilled in the art. The general principles defined in the present invention can be implemented in other embodiments without departing from the spirit or scope of the present invention. Any technical solution obtained by replacing the technical elements in the specific technical solutions described with the same or equivalent or any technical solution that can be obtained by those skilled in the art without creative work on the basis of the specific technical solutions described shall be deemed to fall within the scope of protection of the present invention.

Claims

1. A landing gear door upper lock control logic coordination valve, comprising: A coaxial valve housing integrated with an installation interface for installing an upper latch and provided with an oil inlet nozzle (1) radially communicating with a front coaxial valve chamber, a valve seat (6) and a valve core (8) assembled in the front coaxial valve chamber, a push rod (3) sleeved with a push rod return spring (5), and an end cover (10) provided with an oil outlet nozzle, characterized in that: the push rod (3) sequentially passes through a dust-proof ring (4) and a sealing ring (2), passes through the spring seat plate of the valve seat (6), and is assembled on a bearing; under the action of a pressing mechanism (16), by using the acting force of the movement track (17) of the pressing mechanism, the upper latch drives the push rod (3) through the pressing mechanism, the oil inlet nozzle (1) supplies pressure, the push rod (3) compresses the push rod return spring (5) through a stepped shaft, drives the valve seat (6) to seal the valve core (8), and controls the hydraulic oil to flow out from the oil outlet nozzle; when the upper latch of the cabin door is fully opened, the upper latch applies a pressing force to the push rod (3) through the movement track of the pressing mechanism, the push rod (3) pushes the valve core (8), compresses the valve core return spring (9), separates the valve seat (6), triggers the valve holes distributed on the conical housing of the valve core (8), the hydraulic oil enters the rear end cover valve chamber through the pressure supply oil circuit of the cabin door actuator, flows from the oil outlet nozzle to the cabin door actuator, pushes the cabin door actuator to open the cabin door, compresses the valve core return spring (9) and the push rod return spring (5), and under the action of the elastic force, presses the push rod (3) at the initial position, realizing the simultaneous pressure supply of the upper latch and the cabin door actuator, and completing the control logic of the sequential movement sequence through the trigger-type coaxial valve.

2. The landing gear door upper lock control logic coordination valve according to claim 1, characterized in that: The outer part of the valve seat (6) is provided with a sealing groove for assembling a sealing ring (7), and the end cover (10) is butted against the valve seat (6) through the sealing ring, and sealing rings (7) are arranged on the outer circles of the open ends of the valve seat and the end cover.

3. The landing gear door upper lock control logic coordination valve according to claim 1, characterized in that: When the oil inlet nozzle (1) does not supply pressure, the valve core return spring (9) presses the valve core (8) and the valve seat (6) tightly to prevent the valve seat and the valve core from separating due to vibration and impact conditions on the aircraft, and the push rod return spring (5) presses the push rod at the initial position.

4. The landing gear door upper lock control logic coordination valve according to claim 1, characterized in that: When the oil inlet nozzle (1) supplies pressure, the valve seat seals the valve core, and the oil cannot flow out from the oil outlet nozzle.

5. The landing gear door upper lock control logic coordination valve according to claim 1, characterized in that: When the upper latch of the cabin door is fully opened, the push rod (3) is pressed by the mechanical structure on the upper latch, the push rod (3) pushes the valve core (8) to separate from the valve seat (6), and the oil of the oil inlet nozzle (1) flows through the oil outlet nozzle to the cabin door actuator, and the cabin door actuator opens the cabin door.

Images