Light airborne hydraulic actuator system and control method

Abstract

The invention belongs to the technical field of aircraft design, and relates to a light airborne hydraulic actuator system and a control method.The system comprises an electric telescopic driver, a main hydraulic actuator, a plurality of undercarriage folding and unfolding actuators, a high-pressure air source, an emergency undercarriage unfolding switch and an emergency oil discharge switch; the output end of the electric telescopic driver is connected with the main hydraulic actuator to drive a piston pull rod in the main hydraulic actuator to move, the main hydraulic actuator is communicated with the undercarriage folding and unfolding actuators through pipelines, and piston pull rods of the undercarriage folding and unfolding actuators are connected with an aircraft undercarriage. An inner cavity, close to one side of the piston pull rod, of the undercarriage folding and unfolding actuator is communicated with the main hydraulic actuator through a pipeline and an emergency oil discharge switch arranged on the pipeline, and a high-pressure air source is communicated with the main hydraulic actuator through a pipeline and an emergency undercarriage unfolding switch arranged on the pipeline. The device has the characteristics of high reliability and high safety, and is suitable for light and small manned aircrafts.

Description

Technical Field

[0001] The invention belongs to the technical field of aircraft design, and relates to a light airborne hydraulic actuator system and a control method. Background Art

[0002] At present, all airborne electric hydraulic pumps are composed of electric motors, small plunger pumps, accumulators and other components. This system is derived from the backup hydraulic pumps of large foreign aircraft. However, this system has the disadvantages of being heavy and large in size, and is not very suitable for light and small aircraft. Conventional electric drive actuators have a disadvantage that once the motor fails, important components such as the landing gear cannot be retracted, leading to major flight safety accidents. Therefore, manned aircraft try to avoid using this type of electric actuator directly driven by the motor to retract and extend important mechanisms such as the landing gear. However, light and small aircraft need to have a landing gear retraction and extension function. At the same time, in the future era of all-electric aircraft, light and small aircraft will be in a dilemma in choosing the landing gear retraction and extension actuator. Summary of the invention

[0003] Purpose of the present invention:

[0004] In order to solve the above problems, the present invention provides a light airborne hydraulic actuator system and control method. This electric drive hydraulic system has the characteristics of simple structure, high reliability and high safety, and is suitable for light and small manned aircraft, especially all-electric light and small aircraft. The system directly drives the actuator through the torque motor to push the hydraulic actuator cylinder to generate hydraulic driving force. The hydraulic oil in the hydraulic actuator enters the retracting and extending actuator cylinder of the landing gear and other components to drive the landing gear to retract and extend. The system can also be used in parallel with the emergency pneumatic system to ensure that in the event of motor failure, compressed air can still be used for emergency lowering of the landing gear to ensure safe landing, while making the aircraft system lightest.

[0005] The technical solution of the present invention:

[0006] A light airborne hydraulic actuator system comprises an electric telescopic drive, a main hydraulic actuator, a plurality of landing gear retracting and extending actuators, a high-pressure gas source, an emergency landing gear lowering switch, and an emergency oil drain switch. The output end of the electric telescopic drive is connected to the main hydraulic actuator to drive the internal piston rod of the main hydraulic actuator to move. The main hydraulic actuator is connected to a plurality of landing gear retracting and extending actuators through a pipeline. The piston rod of the landing gear retracting and extending actuator is connected to the aircraft landing gear. The inner cavity of the landing gear retracting and extending actuator close to the piston rod side is connected to the main hydraulic actuator through a pipeline and an emergency oil drain switch arranged on the pipeline. The high-pressure gas source is connected to the main hydraulic actuator through a pipeline and an emergency landing gear lowering switch arranged on the pipeline.

[0007] Furthermore, an actuator piston rod is slidably arranged in the internal cavity of the main hydraulic actuator, the rod end of the actuator piston rod is connected to the output end of the electric telescopic drive, and the piston end of the actuator piston rod divides the internal cavity of the main hydraulic actuator into a left oil chamber and a right oil chamber.

[0008] Furthermore, the high-pressure gas source is a compressed air bottle, which is filled with compressed air or nitrogen with a pressure of 5-10 MPa.

[0009] Furthermore, the emergency landing gear release switch is connected to the left oil chamber of the main hydraulic actuator through a compressed air pipe.

[0010] Furthermore, an actuator cylinder piston rod is slidably arranged inside the landing gear retracting and extending actuator, the rod end of the actuator cylinder piston rod is connected to the aircraft landing gear, and the piston end divides the inner cavity of the landing gear retracting and extending actuator into an upper oil chamber and a lower oil chamber.

[0011] Furthermore, the upper oil chamber is connected to the left oil chamber of the main hydraulic actuator through the upper working oil pipe and the left working oil pipe.

[0012] Furthermore, the lower oil chamber is connected to the emergency oil drain switch through the lower working oil pipe, and the emergency oil drain switch is connected to the right oil chamber of the main hydraulic actuator through the right working oil pipe.

[0013] Furthermore, the lower working oil pipe and the right working oil pipe are connected to the air outside the machine through an emergency oil drain switch.

[0014] A control method for a light airborne hydraulic actuator system,

[0015] When the landing gear needs to be lowered, the pilot turns on the landing gear switch to the lower position, and the electric telescopic drive starts to drive the actuator piston rod to move to the left. The hydraulic oil in the left oil chamber is squeezed and enters the upper oil chamber of the landing gear retraction and extension actuator through the left working oil pipe and the upper working oil pipe. At this time, the pressure in the upper oil chamber increases, pushing the actuator piston rod downward, driving the landing gear to be lowered. At this time, the hydraulic oil in the lower oil chamber is squeezed and enters the right oil chamber through the lower working oil pipe and the right working oil pipe, completing the landing gear lowering action;

[0016] When the landing gear needs to be retracted, the pilot turns on the landing gear switch to the retracted position, and the electric telescopic drive starts to drive the actuator piston rod to move to the right. The hydraulic oil in the right oil chamber is squeezed and enters the lower oil chamber through the lower working oil pipe and the right working oil pipe. At this time, the hydraulic oil pressure in the lower oil chamber increases, pushing the actuator piston rod upward, driving the landing gear to retract. At this time, the pressure in the upper oil chamber increases, and the internal hydraulic oil enters the left oil chamber through the upper working oil pipe and the left working oil pipe, completing the landing gear retraction action;

[0017] When the landing gear needs to be lowered in an emergency, the pilot turns on the emergency landing gear lowering switch. At this time, the emergency oil drain switch connects the lower working oil pipe to the atmosphere, and the hydraulic oil in the lower oil chamber can be discharged out of the aircraft. At the same time, the emergency landing gear lowering switch is turned on, so that the compressed air in the compressed air bottle enters the left oil chamber, which increases the pressure in the left oil chamber, the working oil pipe, the upper working oil pipe and the upper oil chamber, pushing the piston rod of the actuator to move downward, driving the landing gear to be lowered, and at the same time, the hydraulic oil in the lower oil chamber is discharged out of the aircraft, completing the emergency lowering operation of the landing gear.

[0018] Beneficial effects of the present invention:

[0019] The present invention provides a light airborne hydraulic actuator system and a control method. In the entire system, there is no need to add a large number of hydraulic accessories such as solenoid valves and reversing valves, thereby simplifying the system, improving the reliability of the system, and also reducing the weight of the system.

[0020] Compared with the traditional hydraulic system, the motor drives the plunger pump to generate higher pressure, but requires the motor to work continuously, wasting on-board energy. The motor of this solution can be turned on when needed, making rational use of energy.

[0021] Compared with traditional electric actuators, this solution combines the advantages of electric actuators and hydraulic actuators. In the event of a motor actuator failure, the system can still effectively lower the landing gear to ensure flight safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The present invention is a schematic diagram of the working principle of a light airborne hydraulic actuator system. DETAILED DESCRIPTION

[0023] One embodiment of the present invention is to provide a light airborne hydraulic actuator system including an electric telescopic drive 1, a main hydraulic actuator 2, a landing gear retraction and extension actuator 3, a compressed air bottle 4, an emergency landing gear extension switch 5, and an emergency oil drain switch 6.

[0024] The main hydraulic actuator 2 includes a left oil chamber 2-1, a right oil chamber 2-2, an actuator piston pull rod 2-3, a left working oil pipe 2-4, a right working oil pipe 2-6, and a compressed air pipe 2-5.

[0025] The landing gear retraction and extension actuator 3 includes an upper oil chamber 3-1, a lower oil chamber 3-2, an actuator piston pull rod 3-3, an upper working oil pipe 3-4, and a lower working oil pipe 3-5. The system can have multiple actuators connected in parallel, and the composition and principle are the same.

[0026] The emergency oil drain switch 6 can connect the working pipeline 3-5 and the working pipeline 2-6 to ensure the normal operation of the system, and can also connect the working pipeline 3-5 with the outside of the aircraft to ensure that in an emergency state, the hydraulic oil in the lower oil chamber 3-2 can be discharged to the outside of the aircraft through the lower working oil pipe 3-5 and the emergency oil drain switch 6 to ensure that the landing gear is lowered in an emergency.

[0027] The emergency landing gear lowering switch 5 and the emergency oil draining switch 6 are both electronically controlled switches, which are controlled by the pilot or the flight control system, and are beneficial to reducing weight or volume.

[0028] The compressed air bottle 4 contains compressed air or nitrogen at a pressure of 5-10 MPa.

[0029] A second embodiment of the present invention is:

[0030] A light airborne hydraulic actuator system comprises an electric telescopic drive 1, a main hydraulic actuator 2, a plurality of landing gear retracting and extending actuators 3, a high-pressure gas source 4, an emergency landing gear release switch 5, and an emergency oil drain switch 6. The output end of the electric telescopic drive 1 is connected to the main hydraulic actuator 2 to drive the piston rod 2-3 inside the main hydraulic actuator 2 to move. The main hydraulic actuator 2 is connected to the plurality of landing gear retracting and extending actuators 3 through a pipeline. The piston rod 3-3 of the landing gear retracting and extending actuator 3 is connected to the aircraft landing gear. The inner cavity of the landing gear retracting and extending actuator 3 close to the piston rod 3-3 is connected to the main hydraulic actuator 2 through a pipeline and an emergency oil drain switch 6 arranged on the pipeline. The high-pressure gas source 4 is connected to the main hydraulic actuator 2 through a pipeline and the emergency landing gear release switch 5 arranged on the pipeline.

[0031] In this embodiment, an actuator piston rod 2-3 is slidably provided in the internal cavity of the main hydraulic actuator 2, the rod end of the actuator piston rod 2-3 is connected to the output end of the electric telescopic drive 1, and the piston end of the actuator piston rod 2-3 divides the internal cavity of the main hydraulic actuator 2 into a left oil chamber 2-1 and a right oil chamber 2-2.

[0032] In this embodiment, the emergency landing gear release switch 5 is connected to the left oil chamber 2 - 1 of the main hydraulic actuator 2 through the compressed air pipe 2 - 5 .

[0033] In this embodiment, an actuator piston rod 3-3 is slidably arranged inside the landing gear retraction and extension actuator 3, and the rod end of the actuator piston rod 3-3 is connected to the aircraft landing gear, and the piston end divides the inner cavity of the landing gear retraction and extension actuator 3 into an upper oil chamber 3-1 and a lower oil chamber 3-2.

[0034] In this embodiment, the upper oil chamber 3 - 1 is connected to the left oil chamber 2 - 1 of the main hydraulic actuator 2 through the upper working oil pipe 3 - 4 and the left working oil pipe 2 - 4 .

[0035] In this embodiment, the lower oil chamber 3-2 is connected to the emergency oil drain switch 6 through the lower working oil pipe 3-5, and the emergency oil drain switch 6 is connected to the right oil chamber 2-2 of the main hydraulic actuator 2 through the right working oil pipe 2-6.

[0036] In this embodiment, the lower working oil pipe 3 - 5 and the right working oil pipe 2 - 6 are connected to the air outside the machine through the emergency oil drain switch 6 .

[0037] The third embodiment of the present invention is to provide a control method for a light airborne hydraulic actuator system, including three situations:

[0038] The first situation: when the landing gear needs to be lowered, the pilot turns on the landing gear switch to the lower position, and at the same time the electric telescopic drive 1 starts to drive the actuator piston rod 2-3 to move to the left, and the hydraulic oil in the left oil chamber 2-1 is squeezed and enters the upper oil chamber 3-1 of the landing gear retraction and extension actuator 3 through the left working oil pipe 2-4 and the upper working oil pipe 3-4. At this time, the pressure in the upper oil chamber 3-1 increases, pushing the actuator piston rod 3-3 to move downward, driving the landing gear to be lowered. At this time, the hydraulic oil in the lower oil chamber 3-2 is squeezed and enters the right oil chamber 2-2 through the lower working oil pipe 3-5 and the right working oil pipe 2-6, completing the landing gear lowering action.

[0039] The second situation: when the landing gear needs to be retracted, the pilot turns on the landing gear switch to the retracted position, and at the same time the electric telescopic drive 1 starts to drive the actuator piston rod 2-3 to move to the right, and the hydraulic oil in the right oil chamber 2-2 is squeezed and enters the lower oil chamber 3-2 through the lower working oil pipe 3-5 and the right working oil pipe 2-6. At this time, the hydraulic oil pressure in the lower oil chamber 3-2 increases, pushing the actuator piston rod 3-3 upward, driving the landing gear to retract. At this time, the pressure in the upper oil chamber 3-1 increases, and the internal hydraulic oil enters the left oil chamber 2-1 through the upper working oil pipe 3-4 and the left working oil pipe 2-4, completing the landing gear retraction action.

[0040] The third situation: when the landing gear needs to be lowered in an emergency, the pilot turns on the emergency landing gear lowering switch. At this time, the emergency oil discharge switch 6 connects the lower working oil pipe 3-5 to the atmosphere, and the hydraulic oil in the lower oil chamber 3-2 can be discharged out of the aircraft. At the same time, the emergency landing gear lowering switch 5 is turned on, so that the compressed air in the compressed air bottle 4 enters the left oil chamber 2-1, so that the pressure in the left oil chamber 2-1, the working oil pipe 2-4, the upper working oil pipe 3-4 and the upper oil chamber 3-1 increases, pushing the piston rod 3-3 of the actuator to move downward, driving the landing gear to be lowered, and at the same time, the hydraulic oil in the lower oil chamber 3-2 is discharged out of the aircraft, completing the emergency landing gear lowering operation.

[0041] The present invention does not need to add a large number of hydraulic accessories such as electromagnetic valves and reversing valves, thereby simplifying the system, improving the reliability of the system, and also reducing the weight of the system.

[0042] Compared with the traditional hydraulic system, the motor drives the plunger pump to generate higher pressure, but requires the motor to work continuously, wasting on-board energy. The motor of this solution can be turned on when needed, making rational use of energy.

[0043] Compared with traditional electric actuators, this solution combines the advantages of electric actuators and hydraulic actuators. In the event of a motor actuator failure, the system can still effectively lower the landing gear to ensure flight safety.

Claims

1. A lightweight airborne hydraulic actuator system, characterized in that: The invention comprises an electric telescopic drive (1), a main hydraulic actuator (2), a plurality of landing gear retracting and extending actuators (3), a high-pressure gas source (4), an emergency landing gear lowering switch (5), and an emergency oil drain switch (6). The output end of the electric telescopic drive (1) is connected to the main hydraulic actuator (2) to drive the piston pull rod (2-3) inside the main hydraulic actuator (2) to move. The main hydraulic actuator (2) is connected to the plurality of landing gear retracting and extending actuators (3) through a pipeline. The piston pull rod (3-3) of the landing gear retracting and extending actuator (3) is connected to the aircraft landing gear. The inner cavity of the landing gear retracting and extending actuator (3) close to the piston pull rod (3-3) is connected to the main hydraulic actuator (2) through a pipeline and an emergency oil drain switch (6) arranged on the pipeline. The high-pressure gas source (4) is connected to the main hydraulic actuator (2) through a pipeline and an emergency landing gear lowering switch (5) arranged on the pipeline.

2. The lightweight airborne hydraulic actuator system according to claim 1, characterized in that: An actuator piston rod (2-3) is slidably arranged in the internal cavity of the main hydraulic actuator (2); the rod end of the actuator piston rod (2-3) is connected to the output end of the electric telescopic drive (1); and the piston end of the actuator piston rod (2-3) divides the internal cavity of the main hydraulic actuator (2) into a left oil chamber (2-1) and a right oil chamber (2-2).

3. The lightweight airborne hydraulic actuator system according to claim 2, characterized in that: The high-pressure gas source is a compressed air bottle (4), and the compressed air bottle (4) is provided with compressed air or nitrogen with a pressure of 5-10 MPa.

4. The lightweight airborne hydraulic actuator system according to claim 2, characterized in that: The emergency landing gear release switch (5) is connected to the left oil chamber (2-1) of the main hydraulic actuator (2) through a compressed air pipe (2-5).

5. The lightweight airborne hydraulic actuator system according to claim 2, characterized in that: An actuator cylinder piston pull rod (3-3) is slidably arranged inside the landing gear retracting and extending actuator (3), the rod end of the actuator cylinder piston pull rod (3-3) is connected to the aircraft landing gear, and the piston end divides the inner cavity of the landing gear retracting and extending actuator (3) into an upper oil chamber (3-1) and a lower oil chamber (3-2).

6. The lightweight airborne hydraulic actuator system according to claim 5, characterized in that: The upper oil chamber (3-1) is connected to the left oil chamber (2-1) of the main hydraulic actuator (2) through the upper working oil pipe (3-4) and the left working oil pipe (2-4).

7. The lightweight airborne hydraulic actuator system according to claim 5, characterized in that: The lower oil chamber (3-2) is connected to the emergency oil discharge switch (6) via the lower working oil pipe (3-5), and the emergency oil discharge switch (6) is connected to the right oil chamber (2-2) of the main hydraulic actuator (2) via the right working oil pipe (2-6).

8. The lightweight airborne hydraulic actuator system according to claim 7, characterized in that: The lower working oil pipe (3-5) and the right working oil pipe (2-6) are connected to the air outside the machine through the emergency oil drain switch (6).

9. A control method for a lightweight airborne hydraulic actuator system as claimed in any one of claims 1 to 7, characterized in that: When the landing gear needs to be lowered, the pilot turns on the landing gear switch to the lower position, and at the same time, the electric telescopic drive (1) starts to drive the actuator piston rod (2-3) to move to the left, and the hydraulic oil in the left oil chamber (2-1) is squeezed and enters the upper oil chamber (3-1) of the landing gear retraction and extension actuator (3) through the left working oil pipe (2-4) and the upper working oil pipe (3-4). At this time, the pressure in the upper oil chamber (3-1) increases, pushing the actuator cylinder piston rod (3-3) to move downward, driving the landing gear to be lowered, and at this time, the hydraulic oil in the lower oil chamber (3-2) is squeezed and enters the right oil chamber (2-2) through the lower working oil pipe (3-5) and the right working oil pipe (2-6), completing the landing gear lowering action; When the landing gear needs to be retracted, the pilot turns on the landing gear switch to the retracted position, and at the same time the electric telescopic drive (1) starts to drive the actuator piston rod (2-3) to move to the right, and the hydraulic oil in the right oil chamber (2-2) is squeezed and enters the lower oil chamber (3-2) through the lower working oil pipe (3-5) and the right working oil pipe (2-6). At this time, the hydraulic oil pressure in the lower oil chamber (3-2) increases, pushing the actuator piston rod (3-3) to move upward, driving the landing gear to retract. At this time, the pressure in the upper oil chamber (3-1) increases, and the internal hydraulic oil enters the left oil chamber (2-1) through the upper working oil pipe (3-4) and the left working oil pipe (2-4), completing the landing gear retraction action; When the landing gear needs to be lowered in an emergency, the pilot turns on the emergency landing gear lowering switch. At this time, the emergency oil discharge switch (6) connects the lower working oil pipe (3-5) to the atmosphere, and the hydraulic oil in the lower oil chamber (3-2) can be discharged outside the aircraft. At the same time, the emergency landing gear lowering switch (5) is turned on, so that the compressed air in the compressed air bottle (4) enters the left oil chamber (2-1), so that the pressure in the left oil chamber (2-1), the working oil pipe (2-4), the upper working oil pipe (3-4) and the upper oil chamber (3-1) increases, pushing the piston pull rod (3-3) of the actuator cylinder to move downward, driving the landing gear to be lowered, and at the same time, the hydraulic oil in the lower oil chamber (3-2) is discharged outside the aircraft, completing the emergency landing gear lowering operation.

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