CN215043641U

CN215043641U - Hydraulic retraction system for any position of undercarriage

Info

Publication number: CN215043641U
Application number: CN202120985006.4U
Authority: CN
Inventors: 张麒麟; 王力; 苟辽; 唐旭
Original assignee: SICHUAN LINGFENG AVIATION HYDRAULIC MACHINERY CO Ltd
Current assignee: SICHUAN LINGFENG AVIATION HYDRAULIC MACHINERY CO Ltd
Priority date: 2021-05-10
Filing date: 2021-05-10
Publication date: 2021-12-07
Anticipated expiration: 2031-05-10

Abstract

The utility model discloses an undercarriage optional position hydraulic pressure receive and releases system, the motion is reliable with the control accuracy to reliably lock in needs position. The utility model discloses a following technical scheme realizes: the hydraulic control loop for retracting and releasing any position of the undercarriage is formed by the hydraulic electromagnetic reversing valve I and the hydraulic electromagnetic reversing valve II which are connected in parallel through oil filtration by the two combined valves; the hydraulic oil from the oil filter is divided into two paths by the hydraulic electromagnetic reversing valve I and the hydraulic electromagnetic reversing valve II, one path is communicated with an inner and outer retractable actuator cylinder rodless cavity through the hydraulic electromagnetic reversing valve I, high-pressure oil flows into the inner and outer retractable actuator cylinders through a one-way valve in an oil inlet pipeline to drive piston rods of the inner and outer retractable actuator cylinders to extend out, the undercarriage is put down outwards, and the piston rods retract into the undercarriage to retract inwards; when the inner cylinder and the outer cylinder of the undercarriage are in the down position or the retracting position, the electromagnetic reversing valve I for liquid gives an in-place signal through a displacement sensor on the piston bypass, and the inner cylinder and the outer cylinder are controlled to be internally provided with hydraulic locks to lock or unlock at any position in a required position.

Description

Hydraulic retraction system for any position of undercarriage

Technical Field

The utility model belongs to the technical field of aircraft hydraulic system, a mainly be applied to the hydraulic system that control aircraft undercarriage optional position receive and releases.

Background

Most power retraction systems on aircraft are almost hydraulically driven by hydraulic transmission systems. The hydraulic technology is widely applied in the field of aviation mainly because of high hydraulic driving power density and high rapidity. Landing gear is an important component of aircraft for safe takeoff, landing and ground maneuvering. The device is mainly used for supporting the machine body and transferring ground load; absorbing landing energy and controlling landing overload; the ground maneuvers such as airplane halt, sliding, running, turning, braking and the like are realized; preventing the ground resonance and the gliding and running shimmy of the airplane; and the tail beam is protected from being contacted with the ground under the condition that the airplane is abnormally landed. The hydraulic system of the aircraft landing gear is an important component of the aircraft and plays a role in lifting the aircraft during landing and ground running. Important events such as failure to take off and stow away from ground may lead to accident signs or accidents. At present, the retraction and release operation of the landing gear of the aircraft at home and abroad is realized by a hydraulic system. The hydraulic oil of the hydraulic system works in a regulated and controlled state, so that the hydraulic transmission is closely connected with the transmission control. When the hydraulic system works, the hydraulic pump converts rotary mechanical energy transmitted by the motor into pressure energy, and hydraulic oil is transmitted to the executing mechanism to convert the pressure energy of the hydraulic oil into mechanical energy for output. The hydraulic retraction system mainly comprises a retraction actuator cylinder, a locking device and a corresponding control valve. The traditional working circuit of the hydraulic landing gear retraction system consists of a plurality of basic sequence circuits and safety circuits or sequence valves and safety valves. When the undercarriage is normally folded and unfolded, the mechanical handle is operated to open a hydraulic selection valve oil path through the sector wheel and the steel cable to control the folding and unfolding handles of the undercarriage to have 3 positions of 'folding up', 'down' and 'off', and the undercarriage is normally folded and unfolded and folded by the pressure supplied by the hydraulic system A, if the hydraulic system A has a fault and the system is automatically converted into the hydraulic system B to supply pressure to the emergency lowering system, the mechanical handle is adopted to drive the steel cable to open an undercarriage uplock, the undercarriage front undercarriage and the left and right main undercarriages are respectively and correspondingly provided with 2 emergency lowering mechanical handles by means of gravity and pneumatic power, and a proximity sensor control box is arranged in the system to process the relevant position information of the undercarriage. The tail end damping module not only meets the basic retraction function in the retraction process of the undercarriage, but also has the function of damping at the tail end of the retraction actuator cylinder in order to prevent the impact generated due to the over-high locking speed of the undercarriage. The damping module of the landing gear is designed in the hydraulic actuating cylinder and mainly comprises an oil outlet hole and a damping hole. When the undercarriage is normally retracted, hydraulic oil flows out of the oil outlet hole through the damping hole. When the piston moves to the tail end, the piston covers the oil outlet, and hydraulic oil can only flow out through the damping hole. The size of the generated damping is adjusted by setting the size of the damping hole according to the small hole throttling principle, so that the speed of the landing gear when the landing gear is retracted is controlled. And the stroke of the throttle module undercarriage retraction system to the actuating part. The damping hole and the acceleration range of the actuator cylinder have certain requirements, so that the oil ways at the two ends of the retractable actuator cylinder are provided with the throttling hole and the one-way valve which are respectively used for adjusting the time of the retraction and the laying process of the undercarriage. In the process of folding and unfolding the undercarriage, high-pressure oil flows into the actuating cylinder through the one-way valve in the oil inlet pipeline, low-pressure oil flows back to the oil tank through the throttling hole, and the folding and unfolding speed of the undercarriage is adjusted by adjusting the size of the throttling hole in the oil return pipeline. The pressure maintaining module is used for maintaining the pressure inside the actuating cylinder in a set value, absorbing partial impact force with the hydraulic oil inside and protecting the safety in ground experiment, and consists of mainly one-way valve, overflow valve and two-position three-way valve. When the undercarriage is in a standby state, the two-position three-way valve enables the oil inlet and outlet pipelines to be communicated with the overflow valve, and when the internal pressure of the actuating cylinder is smaller than the opening pressure of the overflow valve, a closed system is formed inside the actuating cylinder, so that the actuating cylinder is in a pressure maintaining state. The safety module is arranged in a hydraulic pump and an oil return pipeline of the undercarriage and used for ensuring that a hydraulic system of the undercarriage works under the safety pressure, the safety module consists of a two-position three-way valve and an overflow valve, and the opening and closing conditions of the hydraulic retraction system of the undercarriage can be controlled through the two-position three-way valve. When the hydraulic system of the landing gear works, the overflow valve is positioned in the working circuit. When the system pressure is greater than the safety pressure of the hydraulic system of the undercarriage, the overflow valve is opened to release the pressure, so that the whole hydraulic system of the undercarriage can work under the safety pressure. When the undercarriage is put down, the undercarriage is put down at a high speed under the combined action of hydraulic pressure, gravity and pneumatic power, and the piston of the actuating cylinder is easy to collide with the outer cylinder when moving to the terminal. The hydraulic energy system of the undercarriage comprises a hydraulic system A, a hydraulic system B and a standby hydraulic system, wherein the rated working pressure of the hydraulic system is 21MPa (main undercarriage). When the undercarriage is normally folded and unfolded, the mechanical handle is operated to open the oil circuit of the hydraulic selector valve through the sector wheel and the steel cable. The control undercarriage has 3 positions of 'up' and 'down' and 'off', when the undercarriage is normally retracted and is retracted by the pressure supplied by the hydraulic system A, if the hydraulic system A has a fault, the system is automatically converted into the pressure supplied by the hydraulic system B for emergency lowering, the system adopts a mechanical handle to drive a steel cable to open an undercarriage up lock, the undercarriage front undercarriage and the left and right main undercarriages are lowered by means of gravity and pneumatic power and respectively correspond to emergency lowering mechanical handles, and a proximity sensor control box is arranged in the system to process the relevant position information of the undercarriage. The toothed plate landing gear is used for retracting and releasing a control handle control steel cable, and a handle lock is used for controlling the handle. The landing gear position signals are primarily electrical, mechanical indicator and audible warning signals. The electrical signal is indicative of the position of the landing gear using an indicator light. The electrical signals vary from aircraft to aircraft. However, in general, when the green light is on, the landing gear is put down and locked, and when the red light is on, the position of the landing gear retraction control handle is inconsistent with the position of the landing gear. An audible warning signal is provided to alert the pilot to the landing gear extension prior to landing. Aircraft typically have warning devices for landing gear. Since the flap is released and the throttle is retracted before landing, the warning signal is often correlated to the flap release angle or throttle lever angle. After the aircraft has lowered the flaps to a certain angle, a red warning light is on the instrument panel if the pilot has not yet lowered the landing gear. When the throttle lever receives a certain position, if the landing gear is not put down, the warning horn is automatically switched on. The mechanical indicating signal is usually composed of an indicating rod, a steel cable and a spring. The indicating rod is driven by the undercarriage through a steel cable. The undercarriage retraction indicating rod retracts into the wing or the fuselage, and the undercarriage extension indicating rod extends out. Some aircraft have a mechanical indicator with a scale instead of a pointer stick. When the undercarriage is retracted and extended, the indicator is installed in the cockpit, which indicates the position of the undercarriage. Mechanical indicator signals are mostly used only for small and old aircraft.

At present, landing gear retraction circuits are basically of two types, namely a sequential circuit using a travel switch and a solenoid valve and a sequential circuit using a sequential hydraulic cylinder and a touch sequential valve. Namely, a circuit of a sequence hydraulic cylinder and a touch sequence valve, and high-pressure oil from a pressure supply part is communicated to an electromagnetic valve. When a driver places an undercarriage switch in a down position, the electromagnetic valve is switched to the right position, the high-pressure oil pipe firstly enters a rodless cavity of the unlocking hydraulic cylinder (sequential hydraulic cylinder) to push the piston to move outwards, the upper lock is opened, and meanwhile, the middle oil way is also opened. The high-pressure oil flowing out of the middle oil line is divided into two paths, one path enters a left cavity of the wheel guard plate hydraulic cylinder through the emergency valve to push the piston to move rightwards to open the wheel guard plate, the other path enters a left cavity of the main lifting frame hydraulic cylinder through the hydraulic lock, a one-way throttle valve is installed at the position of a push (right cavity) outlet, the one-way valve is in a closed position in the process of putting down the undercarriage, and the return oil can only flow out through the throttle valve. When the hydraulic system works, under the premise of a certain effective bearing area, the larger the external load is, the larger the required hydraulic oil pressure is, and vice versa. Therefore, the pressure of the system depends on the external load, the load is large, and the pressure of the system is required to be large; the load is small and the required system pressure is small. The speed of movement of the actuator is dependent on the volume, i.e. flow, of hydraulic oil entering its volume per unit time. The flow is large, the speed of the actuating mechanism is high, the flow is zero, and the actuating mechanism does not move. The relationship between the pressure of the hydraulic system and the external load, the speed of the actuator and the flow rate is a very important operating characteristic of the hydraulic transmission. In the process of energy conversion and transmission, because of mechanical friction, pressure loss and leakage loss, the hydraulic oil is easy to generate heat and the total efficiency is reduced; hydraulic drives are particularly sensitive to contamination of the working medium, are prone to system internal and external leaks, and require good sealing and filtration facilities. According to the structural characteristics of the system and the statistics of routine maintenance, the parts which are easy to leak are the high-pressure one-way valve which is freely put down inside the valve sealing rubber ring, the actuating cylinder piston rubber ring and the hydraulic pump. And the parts which are easy to leak are the sealing rubber ring of the actuating cylinder and the hydraulic hose which are broken or damaged. The typical faults of internal leakage or external leakage of the system are that the pump motor does not stop working or works intermittently after the landing gear is put in place; the time for taking up or putting down exceeds the specified 5-lOs. The pressure in the pipeline can not be maintained due to the internal leakage or the external leakage of the system, and when the pressure electric valve senses the pressure reduction, the circuit of the hydraulic pump motor is continuously connected, so that the motor frequently works, and the motor can be damaged due to long-time work. The fault statistics shows that the internal leakage and external leakage faults of the system account for 55.5% of the faults of the system, the pipeline is air-blocked, the valve and the pressure electric valve have the least failure, and the internal leakage of the system has the highest proportion among all fault reasons. This reflects the fact that the hydraulic system is very prone to leakage of the lines and accessories due to long lines, multiple joints, large workload, and high working frequency. When the valve can not be normally opened, the hydraulic pressure at the two ends of the actuating cylinder is unbalanced, so that the undercarriage can not freely fall. The failure is mainly caused by the use fatigue of the valve, and the solution is to replace the valve. The pressure switch is arranged on a cross joint connected with the hydraulic pump mounting bracket assembly, and the on-off of the pump motor is controlled by detecting the pressure of the collecting pipeline. Its failure is divided into two cases. Firstly, actuate the pressure grow, reach 1800psi when receiving the pipeline pressure, the pressure electric door has not cut off motor circuit yet, and pipeline pressure need continue to increase and just can make the electric door close motor stop work, and the trouble shows that the undercarriage receives the back motor that targets in place and does not stop work. Another condition is that the actuation pressure is low, when the take-up pressure has not reached 1800psi, the pressure switch cuts off the motor circuit, and the failure is manifested as the landing gear taking up too long or even failing to take up. For example, in a ground retraction experiment, the pump motor is in an intermittent working condition in the process of retracting the undercarriage, namely the undercarriage can be retracted after multiple on-off processes.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a movement and control accuracy are reliable to the weak point of current undercarriage hydraulic pressure receiving and releasing system, can realize that the optional position receive and releases to the optional position undercarriage hydraulic pressure receiving and releasing system of the reliable locking in needs position.

The utility model provides a technical scheme that its technical problem adopted is: a landing gear arbitrary position hydraulic retraction system comprising: two way combination valve 2 and respectively with the inside and outside receipts and releases actuator cylinder 8, undercarriage receive and releases buffering actuator cylinder 11 and displacement sensor from top to bottom that two way combination valve 2 communicate through oil filter 1 intercommunication, its characterized in that: the two combined valves 2 are in mirror symmetry, and the hydraulic electromagnetic reversing valve I and the hydraulic electromagnetic reversing valve II which are connected in parallel through the oil filter 1 form a hydraulic control loop for retraction and release of any position of the undercarriage; the hydraulic electromagnetic reversing valve I and the hydraulic electromagnetic reversing valve II divide hydraulic oil from the oil filter 1 into two paths, one path is communicated with an inner and outer retractable actuating cylinder 8 rodless cavity through the hydraulic electromagnetic reversing valve I, high-pressure oil flows into the inner and outer retractable actuating cylinders 8 through a one-way valve in an oil inlet pipeline to drive piston rods of the inner and outer retractable actuating cylinders 8 to extend out, the landing gear is put down outwards, and the piston rods retract into the landing gear to retract inwards; when the inner cylinder and the outer cylinder of the undercarriage are in the down position or the retracting position, the hydraulic electromagnetic directional valve I gives an in-place signal through a displacement sensor 10 on a piston bypass, and the inner retractable actuator cylinder 8 and the outer retractable actuator cylinder 8 are controlled to be internally provided with hydraulic locks to lock or unlock at any position at a required position; in a similar way, the other path controls the undercarriage to extend and retract the buffer actuating cylinder 11 up and down through the hydraulic electromagnetic valve II, so that the undercarriage can be extended and retracted in a buffering mode at any position in the up-and-down direction. Meanwhile, working oil in a rod cavity with the buffer actuating cylinder is retracted up and down by the undercarriage and returns to the oil tank through the one-way speed regulating valve or the electromagnetic valve.

The utility model discloses compare and have following beneficial effect in prior art:

the utility model discloses a two way combination valve 2 mirror symmetry, two way combination valve 2 are crossed parallelly connected through oil and are used electromagnetism switching-over valve I and liquid with electromagnetism switching-over valve II for liquid, the hydraulic oil that will come from oil filtration 1 divide into two the tunnel, utilize two way combination valve 2 interior integrated electromagnetism switching-over valve I for liquid, liquid uses electromagnetism switching-over valve II, the process of receiving and releasing and receiving from top to bottom is received and released to the inside and outside of independent control undercarriage respectively, the realization is received and released aircraft undercarriage optional position, and at the reliable locking in closed position, thereby one-way choke valve has great liquid to hinder when making fluid flow actuating cylinder and reduces undercarriage speed and striking. Because the electromagnetic valve at the left end of the undercarriage retracting switch is arranged at the retracting position and the electromagnet is electrified, high-pressure oil enters a rodless cavity of the undercarriage retracting actuator cylinder to push the piston, and oil returning from a rod cavity of the undercarriage retracting actuator cylinder sequentially passes through the hydraulic lock (at the moment, the hydraulic lock is opened by the high-pressure oil), the one-way valve and the electromagnetic valve and returns to the oil tank. The test result shows that the two combined valves which can independently control the retraction process are utilized to work in a coordinated mode, the hydraulic system is basically reliable, the working part meets the function of each action part, and the reliability meets the requirement that the working part is coordinated and consistent. The response characteristic, the movement and control precision of the hydraulic system and the working reliability of the hydraulic system are effectively improved.

Drawings

Fig. 1 is the oil circuit control schematic diagram of the hydraulic retraction system of the landing gear of the utility model.

In the figure: 1 oil filter, 2 combination valves, 3 first pilot-operated check valve group, 4 first pilot-operated check valves, 5 first one-way speed regulating valves, 6 second one-way speed regulating valves, 7 internal and external pressure sensors, 8 internal and external actuator cylinders, 9 internal and external safety valves, 10 internal and external displacement detection sensors, 11 upper and lower buffer actuator cylinders, 12 upper and lower displacement detection sensors, 13 upper and lower pressure sensors, 14 upper and lower safety valves, 15 third one-way speed regulating valves, 16 fourth one-way speed regulating valves, 17 second pilot-operated check valve group, 18 second pilot-operated check valves.

The present invention is further described with reference to the following figures and examples, but the invention is not limited thereby within the scope of the described embodiments. All of these concepts should be considered as within the scope of the present disclosure and the present invention.

Detailed Description

In a preferred embodiment described below with reference to FIG. 1, a landing gear any position hydraulic retraction system includes: the hydraulic lifting device is characterized in that two combined valves 2 are communicated through an oil filter 1, and an inner and outer retractable actuating cylinder 8, an undercarriage up and down retractable buffer actuating cylinder 11 and a displacement sensor are respectively communicated with the two combined valves 2. The two combined valves 2 are in mirror symmetry, and the hydraulic electromagnetic reversing valve I and the hydraulic electromagnetic reversing valve II which are connected in parallel through the oil filter 1 form a hydraulic control loop for retraction and release of any position of the undercarriage; the hydraulic electromagnetic reversing valve I and the hydraulic electromagnetic reversing valve II divide hydraulic oil from the oil filter 1 into two paths, one path is communicated with an inner and outer retractable actuating cylinder 8 rodless cavity through the hydraulic electromagnetic reversing valve I, high-pressure oil flows into the inner and outer retractable actuating cylinders 8 through a one-way valve in an oil inlet pipeline to drive piston rods of the inner and outer retractable actuating cylinders 8 to extend out, the landing gear is put down outwards, and the piston rods retract into the landing gear to retract inwards; when the inner cylinder and the outer cylinder of the undercarriage are in the down position or the retracting position, the hydraulic electromagnetic directional valve I gives an in-place signal through a displacement sensor on a piston bypass, and the inner retractable actuator cylinder 8 and the outer retractable actuator cylinder 8 are controlled to be internally provided with a hydraulic lock to lock or unlock at any position at a required position; in a similar way, the other path controls the undercarriage to extend and retract the actuator cylinder up and down through the hydraulic electromagnetic valve II, so that the undercarriage can be extended and retracted in a buffering mode at any position in the up-and-down direction, and meanwhile working oil in a rod cavity of the undercarriage actuator cylinder returns to the oil tank through the one-way speed regulating valve or the electromagnetic valve.

The two-way combination valve comprises: the hydraulic control system comprises a hydraulic electromagnetic directional valve I for controlling the internal and external retraction process of the undercarriage and a hydraulic electromagnetic directional valve II for controlling the up and down retraction process of the undercarriage, wherein the hydraulic electromagnetic directional valve I is provided with a first hydraulic control one-way valve group 3 and a first hydraulic control one-way valve 4 which are communicated through a two-way pipeline, the one-way valve which can be connected in series with the first hydraulic control one-way valve group 3 is communicated with a first one-way speed regulating valve 5, the first one-way speed regulating valve 5 is communicated with the first hydraulic control one-way valve group 3, an internal and external retraction actuator rodless cavity is communicated with an internal and external retraction actuator rodless cavity through an oil way bypass internal and external retraction pressure sensor 7, and the first hydraulic control one-way valve 4 is communicated with an internal and external retraction actuator 8 rod cavity through an internal and external retraction safety valve 9 of an oil way bypass through a second one-way speed regulating valve 6; in the up-and-down retraction process of the undercarriage, a hydraulic electromagnetic valve II is the same as a hydraulic electromagnetic directional valve I and is also communicated with a second hydraulic one-way valve group 17 and a second hydraulic one-way valve 18 through a two-way pipeline, the second hydraulic one-way valve group 17 is communicated with a fourth one-way speed regulating valve 16 through a series one-way valve, the fourth one-way speed regulating valve 16 is communicated with the second hydraulic one-way valve 18, an up-and-down retraction buffer actuating cylinder 11 rodless cavity is communicated with an up-and-down retraction pressure sensor through a second oil circuit bypass, and the second hydraulic one-way valve 18 is communicated with an up-and-down retraction buffer actuating cylinder 11 rodless cavity through an oil circuit bypass up-and-down safety valve through a third one-way speed regulating valve 15.

The hydraulic lock control circuit for the internal and external retraction of the undercarriage comprises: the hydraulic locking control system comprises a first one-way hydraulic control sequence one-way valve group (3) and a first hydraulic control one-way valve 4 and a first one-way speed regulating valve 5 which are arranged in the same direction, wherein the first one-way hydraulic control sequence one-way valve group (3) is connected with an A port of the first hydraulic control one-way valve 4 on the other branch in parallel through two communicated superposed series-parallel one-way sequence spring valve A input ends, two series-communicated B ports of the one-way sequence spring valve A are connected with a B port corresponding to the first hydraulic control one-way valve 4 in parallel, a second one-way speed regulating valve adjustable throttle valve is connected in series in sequence, and a rod cavity of a single-piston rod cylinder of an inner and outer retractable actuating cylinder 8 is communicated through an oil path bypass inner and outer retractable safety valve 9 to form an actuating cylinder hydraulic locking control loop. Wherein first pilot-controlled check valve group 3 establishes ties two pilot-controlled check valves, wherein two pilot-controlled check valves in first pilot-controlled check valve group 3 connect in series and communicate, in two hydraulic pressure pipelines of the inside and outside receipts and releases pressurized strut 8 of switch-on of electromagnetic directional valve I for liquid, electromagnetic directional valve I for liquid communicates through first pilot-controlled check valve group 3A mouth and first pilot-controlled check valve 4A mouth respectively, the A mouth of first pilot-controlled check valve group 3 bypasses to the B mouth of first pilot-controlled check valve 4 simultaneously, the A mouth of first pilot-controlled check valve 4 bypasses to two B mouths of first pilot-controlled check valve group 3 simultaneously. The hydraulic control one-way valve comprises a valve body, a compression spring and a control piston. The return oil can flow from the port A to the port B all the time. In the reverse direction, is held against the valve seat by the compression spring and system pressure. The pressure oil control piston is pushed to the annular area of the Y oil drain port control piston to be isolated from the port A. The superposed series hydraulic control one-way valve can be used for closing one or two working oil ports, has long leakage-free duration and good stability, oil freely flows from A to B and is stopped in the reverse direction, if pressure oil acts on the valve core, the valve core moves in the direction and pushes the steel ball to leave the valve seat, when the one-way valve is opened by the control oil, the oil can flow from A to B, the pressure is unloaded in a cavity B, the one-way valve is completely opened, and in order to ensure that the two main one-way valves can be reliably closed in the middle position of the reversing valve, an A, B port of the valve is connected with an oil return path. Two ports B of the first hydraulic control one-way valve group 3 and a port B of the first hydraulic control one-way valve 4 are control oil ports, and when high-pressure oil is supplied to the control oil ports, a control piston ejector rod in the hydraulic control one-way valve moves under pressure to jack the one-way valve, so that an oil inlet and outlet way is communicated. When the undercarriage is retracted and extended to a required position from inside to outside, the system cuts off pressure oil, the hydraulic control one-way valve is closed, and hydraulic oil in the inner and outer retraction actuating cylinders cannot flow, so that the undercarriage stays at the position, and the reliable hydraulic locking function is started.

In a similar way, the hydraulic lock control loop for up-down retraction of the undercarriage comprises: the hydraulic control system comprises a second hydraulic control one-way valve group 17 and a second hydraulic control one-way valve 18 which are arranged in the same direction, wherein the first hydraulic control one-way valve group (3) is connected with an A port of the second hydraulic control one-way valve 18 on the other branch in parallel through two communicated superposed series-parallel connection one-way sequence spring valve A input ends, and two series-connection B ports of the one-way sequence spring valve A are connected with a B port corresponding to the second hydraulic control one-way valve group 17 in parallel, and are sequentially connected with an adjustable throttle valve of a second one-way speed regulating valve in series, and an upper safety valve 14 and a lower safety valve 14 which are communicated through an oil way bypass are communicated with a rod cavity of a double-piston rod cylinder of an upper buffer actuating cylinder 11 and a lower buffer actuating cylinder 11. Wherein two pilot operated check valves of putting through have been established ties in the second hydraulic control check valve group 17, in two hydraulic lines of receiving and releasing buffer actuator 11 about the switch-on of liquid with electromagnetic directional valve II, liquid with electromagnetic directional valve II communicates with the A mouth of second pilot operated check valve group 17 and the A mouth of second pilot operated check valve 18 respectively, the A mouth of second pilot operated check valve group 17 the while by pass to the B mouth of second pilot operated check valve 18, the A mouth of second pilot operated check valve 18 by pass to two B mouths of second pilot operated check valve group 17 simultaneously. Two ports B of the second hydraulic control one-way valve group 17 and a port B of the second hydraulic control one-way valve 18 are control ports, and when high-pressure oil is supplied to the control ports, a control piston ejector rod in the hydraulic control one-way valve moves under pressure to jack the one-way valve, so that an oil inlet and outlet way is communicated. When the undercarriage is folded and unfolded up and down to a required position, the system cuts off pressure oil, the hydraulic control one-way valve is closed, hydraulic oil in the upper folding and unfolding buffer actuating cylinder and the lower folding and unfolding buffer actuating cylinder cannot flow, the undercarriage stays at the position, and the reliable hydraulic locking function is started.

The first one-way speed regulating valve 5, the second one-way speed regulating valve 6, the third one-way speed regulating valve 15 and the fourth one-way speed regulating valve 16 are based on the throttle principle of the throttle valve, a set of pressure compensation device is additionally arranged on the internal structure of the throttle valve, the flow is controlled by controlling the integral quantity of pressure proportional to the flow derivative and the flow area, the pressure loss after throttling is improved, and the function of balanced speed regulation is realized.

The internal and external safety valves 9 and the upper and lower safety valves 14 are balanced loops formed by hydraulic one-way throttle valves and reversing valves, W is the external load of the hydraulic cylinder, the one-way throttle valve on the oil return path is in a switching speed regulation state under the control of a second one-way speed regulation valve, pressure oil of a hydraulic source enters the upper cavity of the hydraulic cylinder and conducts a hydraulic control one-way valve, the oil in the lower cavity of the hydraulic cylinder is discharged back to an oil tank through the throttle valve, the hydraulic control one-way valve and the reversing valve, a piston moves downwards, and when the electromagnets 1YA and 2YA are powered off to enable the reversing valve 1 to be in a middle position, the hydraulic control one-way valve is rapidly closed, and the piston immediately stops moving; when the electromagnet 2YA is electrified to switch the reversing valve to the right position, the pressure oil enters the lower cavity of the hydraulic cylinder through the one-way valve to enable the piston to move upwards. The opening of the valve is properly adjusted to prevent overspeed descent, and when the reversing valve is in the middle position, the inlet and the outlet of the hydraulic cylinder are sealed, and the piston can stop. The balance loop has good locking performance and reliable work, and the throttle valve can prevent vibration caused by overspeed during descending of a hydraulic cylinder piston or opening and closing of a hydraulic control one-way valve.

When a landing frame releasing instruction is given, the left position of the hydraulic electromagnetic reversing valve I is electrified to be in the left position, pressure oil enters the rodless cavity of the inner and outer retractable actuating cylinders 8, enters the port B of the first hydraulic control one-way valve 4 to open a hydraulic lock, and oil in the rod cavity of the inner and outer retractable actuating cylinders 8 returns to the oil tank through the speed regulation effect of the second one-way speed regulation valve 6; when the third displacement sensor 10 gives an in-place signal, the electromagnetic reversing valve I for the liquid is powered off and is positioned at the middle position, the hydraulic lock is closed, the oil liquid is sealed in the pipeline, and the inner and outer retractable actuating cylinders 8 are kept at a certain position; when an undercarriage retraction instruction is given, the right position of the hydraulic electromagnetic reversing valve I is electrified to be at the right position, pressure oil enters the rod cavity of the inner and outer retractable actuator cylinders 8 and enters the port B of the first hydraulic control one-way valve group 3 to open a hydraulic lock, and oil in the rodless cavity of the inner and outer retractable actuator cylinders 8 returns to the oil tank through the speed regulation effect of the first one-way speed regulation valve 5, so that the inner and outer retractable processes of the undercarriage are realized.

When a rack-falling instruction is given, the left position of the hydraulic electromagnetic reversing valve II is electrified to be in the left position, pressure oil enters a rodless cavity of the upper and lower retracting buffer actuating cylinder 11, enters a port B of the second hydraulic one-way valve 18 to open a hydraulic lock, and oil in a rod cavity of the upper and lower retracting buffer actuating cylinder 11 returns to the oil tank through the speed regulation function of the third one-way speed regulation valve 15; when the fourth displacement sensor 12 gives a position signal, the electromagnetic reversing valve II for the liquid is powered off and is positioned at the middle position, the hydraulic lock is closed, the oil liquid is sealed in the pipeline, the upper and lower retracting buffer actuating cylinders 11 are kept at a certain position, and if the sealed oil pressure rises to a set value along with the rise of the temperature, the upper and lower retracting safety valves 14 are opened to release the pressure to protect the system; when an undercarriage retraction instruction is given, the right position of the hydraulic electromagnetic reversing valve II is electrified to be in the right position, pressure oil enters the rod cavities of the upper and lower retractable buffer actuating cylinders 11, enters the port B of the second hydraulic control one-way valve group 17 to open a hydraulic lock, and oil in the rod-free cavities of the upper and lower retractable buffer actuating cylinders 11 returns to the oil tank through the speed regulation effect of the fourth one-way speed regulation valve 16, so that the up and down retractable process of the undercarriage is realized.

When the power of the electromagnetic reversing valve I for liquid is cut off and is positioned at a middle position, the hydraulic lock is closed, the oil liquid is sealed in a pipeline, and if the sealed oil pressure rises to a set value along with the rise of the temperature, an internal and external safety valve 9 connected with rod cavities of the internal and external retractable actuating cylinders 8 in parallel is opened, and a pressure relief protection system is arranged.

And when the power of the hydraulic electromagnetic reversing valve II is cut off and is positioned at a middle position, the hydraulic lock is closed, the oil is sealed in a pipeline, and if the sealed oil pressure rises to a set value along with the rise of the temperature, an upper and a lower retractable safety valves 14 connected with rod cavities of the upper and the lower retractable buffer actuating cylinders 11 in parallel are opened, so that a pressure relief protection system is realized.

The foregoing is directed to the preferred embodiment of the present invention, and it is noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design alternative embodiments without departing from the scope of the appended claims. It will be apparent to those skilled in the art that various modifications and improvements can be made without departing from the spirit and substance of the invention, and these modifications and improvements are also considered to be within the scope of the invention.

Claims

1. A landing gear arbitrary position hydraulic retraction system comprising: through oil filter (1) intercommunication two way combination valve (2) with respectively with inside and outside receive and release actuator cylinder (8), undercarriage receive and release buffering actuator cylinder (11) and displacement sensor from top to bottom that two way combination valve (2) communicate, its characterized in that: the two combined valves (2) are in mirror symmetry, and the two combined valves (2) form a hydraulic control loop for retraction and release at any position of the undercarriage through a liquid electromagnetic reversing valve I and a liquid electromagnetic reversing valve II which are connected in parallel through an oil filter (1); hydraulic oil from an oil filter (1) is divided into two paths by a hydraulic electromagnetic reversing valve I and a hydraulic electromagnetic reversing valve II, one path is communicated with an internal and external retractable hydraulic lock control loop of the undercarriage and a rodless cavity of an internal and external retractable actuator cylinder (8) through the hydraulic electromagnetic reversing valve I, high-pressure oil flows into the internal and external retractable actuator cylinder (8) through a one-way valve in an oil inlet pipeline to drive a piston rod of the internal and external retractable actuator cylinder (8) to extend, the undercarriage is put down outwards, and the piston rod retracts into the undercarriage and retracts inwards; when the inner cylinder and the outer cylinder of the undercarriage are in the down position or the retracting position, the hydraulic electromagnetic directional valve I gives an in-place signal through a displacement sensor (10) on a piston bypass, and the inner retractable actuator cylinder and the outer retractable actuator cylinder (8) are controlled to be internally provided with hydraulic locks to lock or unlock at any position in a required position; similarly, the other path controls an undercarriage up-and-down retraction hydraulic lock control loop and an undercarriage up-and-down retraction buffer actuator cylinder (11) through a hydraulic solenoid valve II to realize the buffer retraction of any position of the undercarriage in the up-and-down direction, and simultaneously, working oil in a rod cavity with the undercarriage up-and-down retraction buffer actuator cylinder returns to an oil tank through a one-way speed regulating valve or a solenoid valve.

2. A landing gear any position hydraulic retraction system according to claim 1 wherein: the two-way combination valve comprises: the hydraulic electromagnetic directional control device comprises a hydraulic electromagnetic directional valve I for controlling the internal and external retraction process of the undercarriage and a hydraulic electromagnetic directional valve II for controlling the up and down retraction process of the undercarriage, wherein the hydraulic electromagnetic directional valve I is communicated with a first hydraulic control one-way valve group (3) and a first hydraulic control one-way valve (4) through a two-way pipeline, the first hydraulic control one-way valve group (3) is communicated with a first one-way speed regulating valve (5) through a series one-way valve, the first one-way speed regulating valve (5) is communicated with the first hydraulic control one-way valve group (3), an internal and external retraction actuator cylinder (8) is communicated with a rodless cavity through an oil way bypass internal and external retraction pressure sensor (7), and the first hydraulic control one-way valve (4) is communicated with the internal and external retraction actuator cylinder (8) through an oil way bypass internal and external retraction safety valve (9) through a second one-way speed regulating valve (6) to form a rod cavity.

3. A landing gear any position hydraulic retraction system according to claim 1 wherein: in the up-and-down retraction process of the undercarriage, a hydraulic electromagnetic valve II is the same as a hydraulic electromagnetic directional valve I and is also communicated with a second hydraulic one-way valve group (17) and a second hydraulic one-way valve (18) through a two-way pipeline, the second hydraulic one-way valve group (17) is communicated with a fourth one-way speed regulating valve (16) through a series-connected one-way valve, the fourth one-way speed regulating valve (16) is communicated with a second hydraulic one-way valve (18), an upper retraction buffer actuating cylinder (11) and a lower retraction buffer actuating cylinder (11) are communicated through a second oil-way bypass pressure sensor (13), and the second hydraulic one-way valve (18) is communicated with an upper retraction buffer actuating cylinder (11) and a lower retraction buffer actuating cylinder (11) through a third one-way speed regulating valve (15) and an upper retraction safety valve (14) and a lower retraction buffer actuating cylinder (11) through an oil-way bypass and has a rod cavity.

4. A landing gear any position hydraulic retraction system according to claim 1 wherein: the hydraulic lock control circuit that receive and releases about undercarriage is the same with undercarriage, and wherein, undercarriage inside and outside receive and release hydraulic lock control circuit includes: the hydraulic control system comprises a first hydraulic control one-way valve group (3) arranged in the same direction, a first hydraulic control one-way valve (4) and a first one-way speed regulating valve (5), wherein the first hydraulic control one-way valve group (3) is connected with an A port of the first hydraulic control one-way valve (4) on the other branch in parallel through an A input end of a superposed series-parallel one-way sequence spring valve A of two communicated ports, the two series-parallel first hydraulic control one-way valves (4) of the one-way sequence spring valve A correspond to the B port, a second one-way speed regulating valve adjustable throttle valve is connected in series in sequence, a safety valve (9) is received inside and outside through an oil way bypass, and a rod cavity of a single piston rod cylinder of an actuating cylinder (8) is communicated with the inside and outside.

5. A landing gear any position hydraulic retraction system according to claim 1 wherein: in two hydraulic lines of the internal and external retractable actuating cylinders (8) are communicated with the hydraulic electromagnetic reversing valve I, the hydraulic electromagnetic reversing valve I is communicated with an A port of the first hydraulic control one-way valve group (3) and an A port of the first hydraulic control one-way valve group (4) respectively, the A port of the first hydraulic control one-way valve group (3) is simultaneously bypassed to a B port of the first hydraulic control one-way valve group (4), and the A port of the first hydraulic control one-way valve group (4) is simultaneously bypassed to two B ports of the first hydraulic control one-way valve group (3).

6. A landing gear any position hydraulic retraction system according to claim 1 wherein: two ports B of the first hydraulic control one-way valve group (3) and a port B of the first hydraulic control one-way valve (4) are control oil ports, when high-pressure oil is supplied to the control oil ports, a control piston ejector rod in the hydraulic control one-way valve moves under pressure to jack the one-way valve, so that an oil inlet and outlet way is connected, when the undercarriage is folded and unfolded to a required position inside and outside, the system cuts off the pressure oil, the hydraulic control one-way valve is closed, hydraulic oil in the inner and outer folding and unfolding actuating cylinders cannot flow, the undercarriage stays at the position, and the reliable hydraulic locking function is started.

7. A landing gear any position hydraulic retraction system according to claim 1 wherein: the first one-way speed regulating valve (5), the second one-way speed regulating valve (6), the third one-way speed regulating valve (15) and the fourth one-way speed regulating valve (16) are based on the throttle principle of the throttle valve, a set of pressure compensation device is additionally arranged on the internal structure of the throttle valve, the flow is controlled by controlling the integral quantity of pressure in direct proportion to the flow derivative and the pressure loss after throttling is improved, and the function of balanced speed regulation is realized.

8. A landing gear any position hydraulic retraction system according to claim 1 wherein: two ports B of a second hydraulic control one-way valve group (17) and a port B of a second hydraulic control one-way valve (18) are control oil ports, and when high-pressure oil is supplied to the control oil ports, a control piston ejector rod in the hydraulic control one-way valve moves under pressure to jack the one-way valve, so that an oil inlet and outlet way is communicated; when the undercarriage is folded and unfolded up and down to a required position, the system cuts off pressure oil, the hydraulic control one-way valve is closed, hydraulic oil in the upper folding and unfolding buffer actuating cylinder and the lower folding and unfolding buffer actuating cylinder cannot flow, the undercarriage stays at the position, and the reliable hydraulic locking function is started.

9. A landing gear any position hydraulic retraction system according to claim 1 wherein: when a rack-falling down instruction is given, the left position of the hydraulic electromagnetic reversing valve I is electrified to be in the left position, pressure oil enters a rodless cavity of the inner and outer retractable actuating cylinders (8), enters a port B of the first hydraulic control one-way valve (4) to open a hydraulic lock, and oil in a rod cavity of the inner and outer retractable actuating cylinders (8) returns to an oil tank through the speed regulation effect of the second one-way speed regulation valve (6); when the third displacement sensor (10) gives an in-place signal, the electromagnetic reversing valve I for the liquid is powered off and is positioned at the middle position, the hydraulic lock is closed, the oil liquid is sealed in the pipeline, and the internal and external retractable actuating cylinders (8) are kept at a certain position; when an undercarriage retraction instruction is given, the right position of the hydraulic electromagnetic reversing valve I is electrified to be at the right position, pressure oil enters the rod cavity of the inner and outer retractable actuator cylinders (8), meanwhile, enters the port B of the first hydraulic control one-way valve group (3) to open a hydraulic lock, and oil in the rod-free cavity of the inner and outer retractable actuator cylinders (8) returns to the oil tank through the speed regulation effect of the first one-way speed regulation valve (5), so that the inner and outer retractable processes of the undercarriage are realized.

10. A landing gear any position hydraulic retraction system according to claim 1 wherein: when a rack-falling down instruction is given, the left position of the hydraulic electromagnetic reversing valve II is electrified to be in the left position, pressure oil enters a rodless cavity of the upper and lower retractable buffer actuating cylinders (11), enters a port B of the second hydraulic one-way valve (18) to open a hydraulic lock, and oil in a rod cavity of the upper and lower retractable buffer actuating cylinders (11) returns to an oil tank through the speed regulation function of the third one-way speed regulation valve (15); when the fourth displacement sensor (12) gives a position signal, the electromagnetic reversing valve II for liquid is powered off and is positioned at a middle position, the hydraulic lock is closed, the oil liquid is sealed in the pipeline, the upper and lower retracting buffer actuating cylinders (11) are kept at a certain position, and if the sealed oil pressure rises to a set value along with the rise of the temperature, the upper and lower retracting safety valves (14) are opened to release the pressure protection system; when an undercarriage retraction instruction is given, the right position of the hydraulic electromagnetic reversing valve II is electrified to be in the right position, pressure oil enters an upper and lower retractable buffer actuating cylinder (11) rod cavity, enters a port B of a second hydraulic control one-way valve group (17) to open a hydraulic lock, and oil in a rodless cavity of the upper and lower retractable buffer actuating cylinder (11) returns to an oil tank through the speed regulation effect of a fourth one-way speed regulation valve (16), so that the upper and lower retractable processes of the undercarriage are realized.