JP2007154983A - Hydraulic device, loading device and alighting gear - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reliable hydraulic device in a simple structure. <P>SOLUTION: In place of a conventional hydraulic device actuated by operating fluid, the hydraulic device consists of a hydraulic cylinder having a hydraulic cylinder with a cylinder main body that has a hollow in it and a piston for separating the hollow into a first chamber and a second chamber and being movably guided by the cylinder main body, a gas chamber for storing gas at a first pressure, a hydraulic source having a power port for discharging the operating fluid at a second pressure and a tank port communicating with a tank, a servo valve capable of adjusting flow rate of the operating fluid, an open/close valve capable of opening and closing a flow passage of the operating fluid. The gas chamber and the first chamber are communicated, the second chamber and the tank port are communicated via the open/close valve and the second chamber and the power port are communicated via the servo valve. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to landing gear test equipment for testing hydraulic equipment, load equipment and landing gear landing gear. In particular, the present invention relates to hydraulic equipment, load equipment, and landing gear test equipment that are characteristic of the hydraulic equipment line.

In the industry, hydraulic equipment that operates with hydraulic oil is used.
Various functions are required for hydraulic equipment depending on the purpose of use.
For example, a hydraulic device that is operated by hydraulic oil is used in a load device that applies a load to an object.
For example, there are cases where position and speed control is performed while moving in one direction, a load is applied to an object, and a load device is desired to be used for an apparatus that wants to move at high speed in the other direction.
For example, hydraulic equipment operated by hydraulic oil is used for landing gear test equipment that applies a lateral load to landing gear landing gear.
For example, landing gear test equipment is required to simulate landing or takeoff, to apply a lateral load to the landing gear, unload the lateral load at a predetermined timing, and not to mechanically interfere with the landing gear. .

The flying object needs to change the direction of travel when taking off, landing, or moving on the ground.
For this purpose, the flying object has an landing gear with a steering function.
For example, a commercial large airplane has a main wheel and a steerable neck wheel. A neck wheel is provided at the neck of the airplane and a main wheel is provided at the wing.
In some cases, the main wheel provided in the center of the wing or the fuselage may have a steering function.
The steering device is a rudder pedal or a steering handle, and is operated by a pilot.
The steering handle is provided beside the pilot and is rotated by the pilot's hand. The rudder pedal is provided at the feet of the pilot and is operated by the feet of the pilot.
Usually, the rudder pedal is also used for the operation of the rudder rudder.

The landing gear is composed of wheels, leg structures, and steering devices.
The steering device is a device that steers the steering angle of the wheel according to the operation amount operated by the pilot.
The leg structure supports the wheel rotatably around the wheel axis, and adjusts the rolling direction of the wheel according to the steering angle transmitted from the steering device. When running on the ground, the axis of the wheel shaft is parallel to the ground and faces in the left-right direction.
The leg structure swings the wheel around the swing shaft. The swing axis is substantially perpendicular to the ground.
The leg structure has a possibility of causing a shimmy phenomenon. Disturbances trigger the shimmy phenomenon. When the shimmy phenomenon occurs in the leg structure, the wheel swings violently, which may adversely affect the leg structure.
When designing an landing gear that does not cause this shimmy phenomenon, the specifications of the landing gear are carefully selected.

In the test of the landing gear of the flying object, it may be desired to confirm that no shimmy phenomenon occurs in the landing area of the flying object.
In general, in a test apparatus for a single landing gear, the landing gear is supported by a frame and pressed against the outer circumference of a rotating drum simulated on the ground to perform various tests.
The relative motion of the wheel and the ground is simulated by the tangential speed of the outer peripheral surface of the rotating drum.
In order to surely confirm that the shimmy phenomenon does not occur, it is conceivable as an initial condition that a constant displacement is given to the landing gear laterally, or a constant load is applied to the landing gear laterally.
For example, it is conceivable to use a hydraulic cylinder with a rod, apply a constant load to the wheel axle at the tip of the rod, and retract the rod at a predetermined timing. It is also conceivable that a constant displacement is applied to the wheel axle at the tip of the rod and the rod is retracted at a predetermined timing.

When retracting the rod, it is necessary not to disturb the movement of the landing gear around the swing axis. When the landing gear moves around the swing axis, if the rod interferes with the landing gear, the movement of the landing gear cannot be observed accurately.
Therefore, when the rod is retracted, it is required to move the rod of the hydraulic cylinder at a high speed.
In general, in order to move the rod of the hydraulic cylinder at high speed, high-precision hydraulic equipment elements and large power are required.

US Pat. No. 5,086,995

  The present invention has been devised in view of the problems described above, and aims to provide a highly reliable hydraulic device, load device, and landing gear test device with a simple configuration.

  In order to achieve the above object, a hydraulic device that is operated by hydraulic oil according to the present invention is divided into a cylinder body having a cavity therein and the cavity is divided into a first chamber and a second chamber, and is guided to the cylinder body in a freely movable manner. Hydraulic cylinder having a hydraulic cylinder, a gas chamber storing gas having a first pressure, a power port for discharging hydraulic oil having a second pressure, and a tank port communicating with the tank A gas source and a servo valve capable of adjusting a flow rate of hydraulic oil, and an on-off valve capable of opening and closing a flow path of the hydraulic oil, wherein the gas chamber and the first chamber are communicated with each other, The tank port is communicated via the on-off valve, and the second chamber and the power port are communicated via the servo valve.

According to the configuration of the present invention, the hydraulic cylinder has a cylinder body having a cavity inside, and a piston that divides the cavity into a first chamber and a second chamber and is guided movably in the cylinder body. A gas chamber stores gas having a first pressure. The hydraulic source has a power port that discharges hydraulic oil having a second pressure and a tank port that communicates with the tank. Servo valve can adjust the flow rate of hydraulic fluid. The on-off valve can open and close the hydraulic fluid passage. The gas chamber communicates with the first chamber, the second chamber communicates with the tank port via the on-off valve, and the second chamber communicates with the power port via the servo valve. The
As a result, when the on-off valve closes the flow path, the position or speed of the piston can be controlled by the servo valve, and when the on-off valve opens the flow path, the piston is pushed by the first pressure so that the piston is in the first chamber. It moves from the side to the second chamber side.

  In order to achieve the above object, a load device that operates with hydraulic oil according to the present invention and applies a load to an object is divided into a cylinder body having a cavity inside, and the cavity divided into a first chamber and a second chamber. A hydraulic cylinder having a piston movably guided to the cylinder body, a piston rod having one end connected to the piston and projecting the other end from the cylinder body, and a gas chamber for storing a gas having a first pressure; , A hydraulic power source having a power port for discharging hydraulic oil having a second pressure and a tank port communicating with the tank, a servo valve capable of adjusting the flow rate of the hydraulic oil, and opening and closing the hydraulic oil flow path An open / close valve, wherein the gas chamber and the first chamber communicate with each other, the second chamber and the tank port communicate with each other via the open / close valve, and the second chamber and the power port communicate with each other. Servo bar Comprising a hydraulic equipment communicate with each other through the blanking a supporting device for supporting an object, and was intended to press the other end of the piston rod to an object.

With the configuration of the present invention described above, the hydraulic cylinder has a cylinder body having a cavity inside, a piston that is movably guided to the cylinder body by dividing the cavity into a first chamber and a second chamber, and one end connected to the piston. The other end has a piston rod protruding from the cylinder body. A gas chamber stores gas having a first pressure. The hydraulic source has a power port that discharges hydraulic oil having a second pressure and a tank port that communicates with the tank. Servo valve can adjust the flow rate of hydraulic fluid. The on-off valve can open and close the hydraulic fluid passage. The gas chamber communicates with the first chamber, the second chamber communicates with the tank port via the on-off valve, and the second chamber communicates with the power port via the servo valve. The A support device supports the object.
As a result, the other end of the piston rod is pressed against the object, so that when the on-off valve closes the flow path, the position or speed of the piston can be controlled by the servo valve, and the other end of the piston rod is moved against the object. When the on-off valve opens the flow path, it is pushed by the first pressure, and the piston moves from the first chamber side to the second chamber side, so that the piston rod can be moved.

In order to achieve the above object, an landing gear test apparatus that operates with hydraulic oil according to the present invention and applies a load to a landing gear landing gear, a cylinder main body having a cavity inside, a first chamber, a second cavity A hydraulic cylinder having a piston which is divided into chambers and is movably guided to the cylinder body, one end connected to the piston and the other end protruding from the cylinder body, and a gas having a first pressure A hydraulic source having a gas chamber for storage, a power port for discharging hydraulic oil having a second pressure, and a tank port communicating with the tank, a servo valve capable of adjusting the flow rate of hydraulic oil, and a flow of hydraulic oil An opening / closing valve capable of opening and closing a path, wherein the gas chamber and the first chamber communicate with each other, the second chamber and the tank port communicate with each other via the opening / closing valve, and the second chamber The power po A hydraulic device which bets are communicated via the servo valve,
A support device for supporting the landing gear, and a rotating drum having an outer peripheral surface that simulates a landing surface contacting the landing gear wheel, and the other end of the piston rod is pressed against the wheel shaft of the landing gear wheel. .

With the configuration of the present invention described above, the hydraulic cylinder has a cylinder body having a cavity therein, a piston that is movably guided to the cylinder body by dividing the cavity into a first chamber and a second chamber, and one end connected to the piston. The other end has a piston rod protruding from the cylinder body. A gas chamber stores gas having a first pressure. The hydraulic source has a power port that discharges hydraulic oil having a second pressure and a tank port that communicates with the tank. Servo valve can adjust the flow rate of hydraulic fluid. The on-off valve can open and close the hydraulic fluid passage. The gas chamber communicates with the first chamber, the second chamber communicates with the tank port via the on-off valve, and the second chamber communicates with the power port via the servo valve. The A support device supports the landing gear. A circumferential surface that simulates the landing surface of the rotating drum is in contact with the wheels of the landing gear.
As a result, the other end of the piston rod is pressed against the support shaft of the landing gear wheel,
When the opening / closing valve closes the flow path, the position and speed of the piston can be controlled by the servo valve, the other end of the piston rod can be moved with respect to the landing gear, and when the opening / closing valve opens the flow path, Pushed by the pressure, the piston moves from the first chamber side to the second chamber side, the other end of the piston rod is retracted, and the landing gear can be tested.

Furthermore, the landing gear test apparatus according to the embodiment of the present invention is such that the force pushing the piston by the second pressure is larger than the force pushing the piston by the first pressure, and the on-off valve closes the flow path. The servo valve adjusts the flow rate of the hydraulic oil to move the piston rod toward the wheel shaft, and the opening / closing valve opens the flow path of the hydraulic oil at a predetermined timing.
With the above-described configuration of the present invention, the force that pushes the piston by the second pressure is greater than the force that pushes the piston by the first pressure, and the servo valve causes the flow rate of hydraulic oil when the on-off valve closes the flow path. The piston rod is moved with respect to the landing gear, and the on-off valve opens the hydraulic fluid passage at a predetermined timing. Therefore, the piston rod is pushed by the piston rod, and the pressing is stopped at the predetermined timing. By retracting the rod, interference between the landing gear and the piston rod can be prevented, and the transient motion of the landing gear can be observed.

Furthermore, the landing gear test apparatus according to the embodiment of the present invention may be configured such that the predetermined timing is when the moving distance of the piston rod exceeds a predetermined value or when the thrust of the piston rod exceeds a predetermined value. This is one of the timings.
According to the configuration of the present invention, the predetermined timing is one of the timing when the moving distance of the piston rod exceeds a predetermined value or the thrust of the piston rod exceeds the predetermined value. The initial displacement or initial load can be removed after applying a predetermined value of initial displacement to the landing gear or after applying a predetermined value of initial load to the landing gear.

As described above, the hydraulic equipment, load equipment, and flying object landing gear test equipment according to the present invention have the following effects due to their configurations.
Hydraulic pressure that divides the cavity of the hydraulic cylinder into a first chamber and a second chamber with a piston, introduces a gas having a first pressure into the first chamber, and generates hydraulic oil having a second pressure in the second chamber A high-pressure hydraulic oil is introduced from a servo valve connected to the power source, and an open / close valve is provided in the middle of the flow path connecting the second chamber and the tank port of the hydraulic power source. The position or speed of the piston can be controlled by the valve. When the on-off valve opens the flow path, the piston is pushed by the first pressure, and the piston moves from the first chamber side to the second chamber side.
The cavity of the hydraulic cylinder is divided into a first chamber and a second chamber by a piston connected to a piston rod, a gas having a first pressure is introduced into the first chamber, and a second pressure is applied to the second chamber. High pressure hydraulic fluid is introduced from a servo valve connected to a hydraulic pressure source that generates hydraulic fluid, and an open / close valve is provided in the middle of the flow path connecting the first chamber and the hydraulic power source tank port. The other end of the piston rod When the on-off valve closes the flow path, the position and speed of the piston can be controlled by the servo valve, the other end of the piston rod can be moved relative to the object, and the on-off valve When the flow path is opened, the piston is pushed by the first pressure, the piston moves from the first chamber side to the second chamber side, and the other end of the piston rod can be retracted.
Also, the cavity of the hydraulic cylinder is partitioned into a first chamber and a second chamber by a piston connected to a piston rod, a gas having a first pressure is introduced into the first chamber, and a second pressure is applied to the second chamber. High pressure hydraulic oil is introduced from a servo valve connected to a hydraulic pressure source that generates hydraulic oil, and an open / close valve is provided in the middle of the flow path connecting the first chamber and the tank port of the hydraulic power source. When the open / close valve closes the flow path, the position and speed of the piston can be controlled by the servo valve and the other end of the piston rod is supported by the support device. When the opening / closing valve closes the flow path, the servo valve can control the position and speed of the piston, and the other end of the piston rod can be moved relative to the landing gear. Valve opens the flow path , Is pushed by the first pressure, the piston is moved from the side of the first chamber toward the second chamber, and saves the other end of the piston rod, it testing the landing gear.
Further, when the piston pressure by the second pressure is larger than the force pushing the piston by the first pressure, the servo valve adjusts the flow rate of the hydraulic oil when the on-off valve closes the flow path, and the piston rod Is moved to the landing gear side, and the on-off valve opens the hydraulic oil flow path at a predetermined timing, so the piston rod is pushed at the predetermined timing by pushing the landing gear with the piston rod, and the piston rod is retracted. Interference between the landing gear and the piston rod is prevented, and the transient motion of the landing gear can be observed.
In addition, since the predetermined timing is one of the timing when the moving distance of the piston rod exceeds a predetermined value or the thrust of the piston rod exceeds the predetermined value, the landing gear has a predetermined timing. The initial displacement or initial load can be removed after applying the initial displacement of the value or after applying a predetermined value of the initial load to the landing gear.
Therefore, highly reliable hydraulic equipment, load equipment, and landing gear test equipment can be provided with a simple configuration.

  The best mode for carrying out the present invention will be described below with reference to the drawings. In each figure, common portions are denoted by the same reference numerals, and redundant description is omitted.

A hydraulic device according to an embodiment of the present invention and a load device using the hydraulic device will be described with reference to the drawings.
FIG. 1 is a line system diagram of a hydraulic device according to an embodiment of the present invention. FIG. 2 is a conceptual diagram of a test apparatus according to an embodiment of the present invention. FIG. 3 is a front view of the test apparatus according to the embodiment of the present invention. FIG. 4 is a plan view of the test apparatus according to the embodiment of the present invention. FIG. 5 is a sequence diagram 1 of the test apparatus according to the embodiment of the present invention. FIG. 6 is a second sequence diagram of the test apparatus according to the embodiment of the present invention.

In the following, for convenience of explanation, a case where the load device is used as a test device for testing the shimmy of the landing gear of the flying object will be described as an example.
The load device is operated by hydraulic oil and is used to apply a load to the landing gear of the flying object.
First, the landing gear landing device will be described.
The landing gear 10 for a flying object is a device that supports the flying object at the time of landing, and includes a wheel 11, a wheel shaft 12, a leg structure 13, and a landing sensor (not shown).

The landing gear is steered by a steering device (not shown).
The steering device is a device that outputs an operation amount corresponding to the operated physical amount.
For example, airplane control devices are a rudder pedal and a steering handle.
The rudder pedal is a pedal operated by a pilot with his / her foot. When the pair of left and right rudder pedals are stepped on, the wheels swing around the vertical axis in accordance with the stepped stroke. Normally, when the pilot steps on the rudder pedal, in addition to steering the wheel, the direction of the rudder rudder can be manipulated.
The steering handle is provided on the side of the pilot and is operated by turning by hand. When the steering handle is turned, the wheel 11 can be steered at a large angle.

The wheel 11 is a wheel that is rotatably supported by a wheel shaft that is fixed to the lower end of the leg structure 13.
For example, the wheel 11 is a rubber tire fitted on the wheel and the outer periphery of the wheel.
In general, a pair of wheels are attached with the lower part of the leg structure sandwiched from the left and right, and a case where one wheel is attached in a fork shape.
The wheel 11 is rotatably supported by the wheel shaft 12 and rotates around the axis of the wheel shaft.

The leg structure 13 is a structure that is supported by the main body of the flying body and rotatably supports the wheels 11.
For example, the leg structure 13 is supported by the main body of the flying body and supports the wheel shaft 12. The wheel shaft 12 supports the wheel 11 rotatably. The leg structure 13 can expand and contract the distance between the support point with the flying object and the support point with the wheel 11.
The posture of the leg structure 13 can be changed between the retracted posture and the landing posture.
The retracted posture is a posture in which the landing gear 10 is stored in the main body of the flying object.
The landing posture is a posture in which the landing gear 10 is exposed to the outside of the main body of the flying object.
In the landing posture, the longitudinal direction of the leg structure 13 is along the vertical direction.
For example, the leg structure 13 includes an upper leg column 13a, a lower leg column 13b, and a storage mechanism 13c.
The lower pedestal 13b is guided by the upper pedestal 13a so as to extend and contract in the longitudinal direction. The lower pedestal 13b is urged by the urging means in a direction extending in the longitudinal direction.
One end of the upper pedestal 13a is supported by the flying body.
The lower pedestal 13b is supported by one end at the other end of the upper pedestal 13a so as to be movable by a predetermined distance in the longitudinal direction.
The storage mechanism 13c is a link mechanism that changes the posture of the leg structure 13 between the storage posture and the landing posture.

The landing sensor is a sensor that outputs an off signal when an airplane load does not act on the wheel 30, and outputs an on signal when an airplane load acts on the wheel 11.
One of the landing sensors is a WOW sensor.
Here, WOW is an abbreviation for Weight On Wheel.
For example, the WOW sensor is a limit sensor that is provided in the leg structure 13 and outputs an ON signal when the lower pedestal contracts.
If the wheel 11 is not grounded, the load of the flying object does not act on the wheel 11, the leg structure 13 extends, and the limit sensor outputs an off signal. When the wheel 11 comes in contact with the ground, the load of the flying object acts on the wheel 11, the lower pedestal 13b enters the upper pedestal 13a, and the limit switch outputs an ON signal.

Next, hydraulic equipment according to an embodiment of the present invention, load equipment using the hydraulic equipment, and landing gear test equipment using the load equipment will be described with reference to the drawings.
The landing gear test device is a testing device that is operated by hydraulic oil and performs a test by applying a load to the landing gear, and includes a hydraulic device 100, a support device 200, a rotating drum 300, and a measuring device 400.
In this case, the hydraulic device 100 and the support device 200 correspond to load devices.

  The hydraulic device 100 is a device that operates with hydraulic oil, and includes a hydraulic cylinder 110, a gas chamber 120, a hydraulic source 130, a servo valve 140, an on-off valve 150, and a load cell 160.

The hydraulic cylinder 110 includes a cylinder body 111, a piston 112, a piston rod 113, a rod end 114, and a linear sensor 115.
The cylinder body 111 is a structure having a cavity inside.
For example, the cylinder body 111 includes a rod side head cover, a cylinder tube, a foot side head cover, and a tie rod.
A cylinder tube is a cylindrical mechanical element that surrounds a cavity.
The rod side head cover is fixed to one end of the cylinder tube, and the foot side head cover is fixed to the other end of the cylinder tube. A tie rod connects the rod-side head cover, the cylinder tube, and the foot-side head cover.
The piston 112 is a mechanical element that divides a cavity into a first chamber H1 and a second chamber H2 and is guided to the cylinder body 111 so as to be movable. The piston 112 is guided by the cylindrical inner wall of the cylinder tube and can move in the longitudinal direction.
The rod side port passes through the rod side head cover and communicates with the first chamber H1.
The foot side port passes through the foot side head cover and communicates with the second chamber H2.
The piston rod 113 is a rod-like mechanical element having one end connected to the piston 112 and the other end protruding from the cylinder body. The piston rod 113 penetrates the rod side head cover.
The rod end 114 is a member fixed to the other end of the piston rod 113. The free end of the rod end 114 has a hemispherical shape.
The linear sensor 115 is a sensor that measures the expansion / contraction distance of the piston rod 113. For example, the linear sensor 115 outputs the output value corresponding to the position of the rod end 114 in the direction in which the piston rod 113 extends, with the position of the rod end 114 when the piston rod 113 is contracted the most.

The gas chamber 120 is a container that stores a gas having a first pressure P1.
For example, the gas is nitrogen gas.
Nitrogen filled in the gas cylinder 121 is depressurized by the pressure reducing valve and stored in the gas chamber 120.

The hydraulic power source 130 is a device having a power port P and a tank port T.
The power port P discharges hydraulic oil having the second pressure P2.
The oil pump raises the hydraulic oil accumulated in the tank to the second pressure P2 and supplies it to the power port P.
The force pushing the piston with the second pressure P2 may be greater than the force pushing the piston with the first pressure P1.
Typically, the second pressure P2 is greater than the first pressure P1.
For example, the first pressure P1 is 70 atm and the second pressure P2 is 210 atm.
The tank port T communicates with the tank. Typically, the pressure at the tank port T is atmospheric pressure.

The servo valve 140 is a valve capable of adjusting the flow rate of the hydraulic oil.
The servo amplifier 141 drives the servo valve 140.
For example, the servo driver 141 is given the output value and the command value of the linear sensor 115, adjusts the opening of the flow path of the servo valve 140 by feedback control, and outputs the command of the linear sensor that detects the moving position of the piston. Move the piston to match the value.

The on-off valve 150 is a valve capable of opening and closing the hydraulic oil flow path.
The on-off valve 150 can be in one state of opening or closing the hydraulic oil flow path.
For example, the on-off valve 150 is a four-way valve that can be switched by an electromagnetic solenoid.

The gas chamber 120 and the first chamber H1 are communicated with each other.
A gas communication pipe 122 communicates the gas chamber 120 and the rod side port.

The second chamber H2 and the tank port T are communicated with each other via the on-off valve 150.
A tank connection pipe 151 communicates the foot side port and the tank port T.
The on-off valve 150 is provided in the middle of the tank connection pipe 151.

The second chamber H2 and the power port P are communicated with each other via the servo valve 140.
A power connection pipe 142 communicates the foot side port and the power port P.
A servo valve 140 is provided in the middle of the power connection pipe 142.

The support device 200 is a device that supports an object.
For example, the support device 200 is a device that supports the landing gear 10 and includes a frame 210, an elevating mechanism 220, a cargo 230, and a leg attachment jig 240.
The frame 210 is a main structure that supports the support device 200.
The elevating mechanism 220 is a mechanism that raises and lowers the cargo 230 and applies an upward load to the cargo 230, and includes an air cylinder 221 that applies an upward load, a lifting hydraulic cylinder 222, and a mass travel 223.
The air cylinder 221 is an air cylinder that adjusts the cargo weight applied to the landing gear by applying an upward load to the cargo 230.
The lifting / lowering hydraulic cylinder 222 is a hydraulic cylinder that raises and lowers the landing gear.
The lifting / lowering hydraulic cylinder 222 moves the cargo 230 according to a predetermined schedule based on the measured value of the mass travel 223.
The mass travel 223 is a sensor that measures the vertical position of the cargo 230.

The cargo 230 is a structure that can be raised and lowered while being guided by the frame 210.
The mass of the cargo 230 simulates the added inertial mass added to the landing gear attached to the actual flying object.

  The leg attachment jig 240 is a jig for attaching the landing gear 10 to the cargo 230. The leg attachment jig 240 simulates a connection portion of an actual landing gear landing device.

The rotary drum 300 is a structure having an outer peripheral surface S that simulates landing on the landing gear wheels.
The outer peripheral surface S of the rotating drum 300 can contact the wheels of the landing gear.
The rotating drum 300 is rotated by a driving device. The tangential speed of the outer peripheral surface S simulates the ground speed of the flying object.

When the on-off valve 150 closes the flow path, the servo valve 140 can adjust the flow rate of the hydraulic oil and move the piston rod to the landing gear side.
The on-off valve can open the hydraulic fluid flow path at a predetermined timing.

The predetermined timing may be when the movement distance of the piston rod exceeds a predetermined value.
For example, when the on-off valve 150 closes the flow path, the servo valve 140 adjusts the flow rate of the hydraulic oil and moves the piston rod to the landing gear side.
When the output of the linear sensor 115 reaches a predetermined value, the on-off valve opens the hydraulic fluid passage.

The predetermined timing may be when the thrust of the piston rod exceeds a predetermined value.
For example, when the on-off valve 150 closes the flow path, the servo valve 140 adjusts the flow rate of the hydraulic oil and moves the piston rod to the landing gear side.
When the output of the load cell 160 reaches a predetermined value, the on-off valve opens the hydraulic fluid passage.

  The predetermined timing may be an earlier time when the moving distance of the piston rod exceeds a predetermined value or when the thrust of the piston rod exceeds a predetermined value.

The measuring device 400 is a device that measures the motion and posture of an object.
For example, the measuring device 400 includes a steering angle measuring device 410 and a rolling angle measuring device 420.
The steering angle measurement device 410 includes a pair of laser displacement meters 411 and a pair of reflection mirrors 412.
A pair of reflecting mirrors 412 is provided at both ends of the wheel shaft 12.
A pair of laser displacement meters 411 measures the displacement in the front-rear direction to the pair of reflection mirrors.
The steering angle measurement device 410 calculates a steering angle from the difference between the values of the pair of laser displacement meters 411 and the distance between the pair of reflection mirrors 412.

The rolling angle measurement device 420 includes one laser displacement meter 421 and one reflection mirror 422.
One reflection mirror 422 is provided at the end of the wheel shaft.
One laser displacement meter 421 measures the horizontal displacement of the reflection mirror 422.
The rolling angle measurement device 420 calculates the rolling angle from the value of the laser displacement meter 421.

Next, operations of the hydraulic device, the load device, and the landing gear test device according to the embodiment of the present invention will be described with reference to the drawings.
First, a case where the predetermined timing is when the movement distance of the piston rod exceeds a predetermined value will be described.
FIG. 5 shows a sequence diagram at that time.
First, the support device 200 lifts the landing gear 10, and there is a gap between the wheel 11 and the outer peripheral surface S of the rotating drum 300.
The rod end 114 of the hydraulic cylinder 110 is farthest from the landing gear 10.
The rotating drum 300 rotates, and the tangential speed of the outer peripheral surface S matches the ground speed of the flying vehicle.

The lifting / lowering hydraulic cylinder 222 lowers the cargo 230.
The landing gear approaches the outer peripheral surface of the rotary drum 300.
When the cargo 230 further descends, the wheel 11 contacts the outer peripheral surface of the rotary drum 300 and the leg structure 13 contracts.
When the leg structure 13 contracts, the landing sensor outputs an ON signal.

When the landing sensor outputs an ON signal, the servo driver 141 is given a command value that increases from zero to a constant value at a constant increment per unit time.
The servo valve 140 adjusts the flow path in accordance with a command from the servo driver 141 to bring the rod end 114 close to the load receiving jig 170 at a constant speed and stop it at a position separated by a predetermined distance.

When a predetermined time elapses, a constant value step input is given to the servo driver 141.
The servo valve 140 adjusts the flow path according to the command of the servo driver 141, the rod end 114 is brought close to the landing gear at the maximum speed, and the rod end 114 is applied to the load receiving jig 170.
The maximum speed is a speed determined by the capabilities of the servo valve 140 and the hydraulic cylinder, the first pressure, the second pressure, the control gain set in the servo driver, and the like.
The rod end 114 contacts the load receiving jig 170 and further advances.
When the rod end 114 moves forward, the landing gear bends according to the force generated at the rod end 114.
The measuring device 400 measures and records the steering angle and rolling angle of the landing gear 10.

When the rod end 114 further advances and the rod end advance distance reaches a predetermined limit value, the output of the linear sensor reaches the limit value, and the on-off valve opens the flow path.
The second chamber H2 of the hydraulic cylinder 110 is connected to the tank port T of the hydraulic power source 130, and the pressure in the second chamber H2 rapidly decreases.
The gas having the first pressure flows into the first chamber and moves the piston 112 from the first chamber to the second chamber.
Since the piston 112 moves backward, the rod end 114 moves backward, and the contact between the rod end 114 and the load receiving jig 170 is made.

The landing gear swings toward the retracted rod end 114, and due to its elasticity, transient vibrations occur in the landing gear.
The measuring device 400 observes the transient vibration of the landing gear.

When the command value to the servo driver 141 is returned to zero and the on-off valve 150 closes the flow path, the hydraulic device returns to the initial state.
When the observation of the transient vibration is completed, the lifting / lowering hydraulic cylinder 222 raises the cargo 230, and the support device returns to the initial state.

Next, a case where the predetermined timing is when the thrust of the piston rod exceeds a predetermined value will be described.
FIG. 6 shows a sequence diagram at that time.
First, the support device 200 lifts the landing gear 10, and there is a gap between the wheel 11 and the outer peripheral surface S of the rotating drum 300.
The air cylinder 221 applies a force to the landing gear that is equal to the lift that the actual flying body applies to the landing gear.
The rod end of the hydraulic cylinder is farthest from the landing gear.
The rotating drum 300 rotates, and the tangential speed of the outer peripheral surface S matches the ground speed of the flying vehicle.

The lifting / lowering hydraulic cylinder 222 lowers the cargo 230.
The landing gear approaches the outer peripheral surface of the rotary drum 300.
When the cargo 230 further descends, the wheel 11 contacts the outer peripheral surface of the rotary drum 300 and the leg structure 13 contracts.
When the leg structure 13 contracts, the landing sensor outputs an ON signal.

When the landing sensor outputs an ON signal, the servo driver 141 is given a command value that increases from zero to a constant value at a constant increment per unit time.
The servo valve 140 adjusts the flow path according to the command of the servo driver 141, and the rod end 114 is brought close to the load receiving jig 170 at a constant speed and stopped at a position separated by a predetermined distance.

When a predetermined time elapses, a constant value step input is given to the servo driver 141.
The servo valve 140 adjusts the flow path in accordance with a command from the servo driver 141 to bring the rod end 114 close to the landing gear at the maximum speed, and applies the rod end 114 to the load receiving jig.
The maximum speed is a value determined by the capabilities of the servo valve 140 and the hydraulic cylinder, the first pressure, and the second pressure.
The rod end 114 contacts the load receiving jig 170 and further advances toward the landing gear.
When the rod end 114 moves forward, the landing gear bends according to the force generated at the rod end 114.
The load cell 160 measures the force generated at the rod end.
The measuring device 400 measures and records the steering angle and rolling angle of the landing gear 10.

When the rod end 114 further moves forward and the value measured by the load cell 160 reaches a predetermined limit value, the on-off valve opens the flow path.
The second chamber H2 of the hydraulic cylinder 110 is connected to the tank port T of the hydraulic power source 130, and the pressure in the second chamber H2 rapidly decreases.
The piston 112 is moved backward by flowing into the first chamber of the gas gas having the first pressure P1.
Since the piston 112 moves backward, the rod end 114 moves backward, and the contact between the rod end 114 and the load receiving jig 170 is made.

The landing gear swings toward the retracted rod end 114, and due to its elasticity, transient vibrations occur in the landing gear.
The observation device observes the transient vibration of the landing gear.

When the command value to the servo driver 141 is returned to zero and the on-off valve 150 closes the flow path, the hydraulic device returns to the initial state.
The lifting / lowering hydraulic cylinder 222 raises the cargo 230, and the support device returns to the initial state.

  The predetermined timing may be an earlier timing when the moving distance of the piston rod exceeds a predetermined value or when the thrust of the piston rod exceeds a predetermined value.

Hereinafter, the transient vibration of the landing gear will be described.
When the rod end 114 moves backward, the landing gear swings toward the retracted rod end 114 due to its elastic force, and free vibration occurs in the landing gear.
The free vibration is expected to be settled in a predetermined time due to the structural damping of the landing gear. However, if the specifications of the landing gear are not appropriate, shimmy vibration may occur with free vibration as an initial disturbance.
Shimmy vibration is known as a self-excited vibration phenomenon that occurs in landing gears.
Transient vibration is a combination of these free vibration and shimmy vibration.
When the difference between the first pressure P1 and the second pressure P2 is set appropriately, the rod end 114 moves backward at an appropriate speed, so that the load receiving jig 170 moved by free vibration or shimmy vibration of the landing gear is moved to the rod end 114. It is possible to prevent mechanical interference.
When the first pressure P1 is increased, the rod end 114 moves backward at a high speed, so that the load receiving jig 170 moved by free vibration or shimmy vibration of the landing gear is less likely to cause mechanical interference with the rod end 114.
When the first pressure P1 is small, the retracting speed of the rod end 114 is small, and the load receiving jig 170 that moves due to free vibration or shimmy vibration of the landing gear may collide with the rod end 114. When such a phenomenon occurs, the free vibration or shimmy vibration of the landing gear cannot be properly observed.

If the hydraulic equipment, the load equipment, and the landing gear test equipment of the above-described embodiment are used, the following effects are exhibited.
The cavity of the hydraulic cylinder 110 is partitioned into a first chamber H1 and a second chamber H2 by a piston 112 connected to a piston rod 113, the piston rod 113 is protruded from the rod side head cover, and a first pressure P1 is applied to the first chamber H1. The high pressure hydraulic fluid is introduced from the servo valve 140 connected to the hydraulic pressure source 130 that introduces the gas and generates the hydraulic fluid having the second pressure P2 in the second chamber H2, and the first chamber H1 and the hydraulic pressure source Since the open / close valve 150 is provided in the middle of the flow path connecting the tank port T of 130 and the other end of the piston rod 113 is pressed against the device under test, when the open / close valve 150 closes the flow path, the servo valve 140 causes the position of the piston 112 to move. When the other end of the piston rod 113 can be controlled with a predetermined force and the on-off valve 150 opens the flow path, the first pressure P1 is pressed and the piston can be controlled. 12 is moved from the side of the first chamber H1 to the side of the second chamber h2, can save the other end of the piston rod 113.
Further, since the force pushing the piston 112 by the second pressure P2 is larger than the force pushing the piston 112 by the first pressure P1, the piston rod 113 is adjusted when the servo valve 140 adjusts the flow rate when the on-off valve 150 closes the flow path. When the open / close valve 150 opens the flow path, the piston rod 113 contracts.
In addition, since the other end of the piston rod 113 is pressed against the wheel shaft of the landing gear supported by the support device 200 using the hydraulic device described above, when the on-off valve 150 closes the flow path, the servo valve 140 causes the position of the piston 112 to move. When the speed can be controlled and the other end of the piston rod 113 can be moved to the wheel shaft side of the landing gear wheel 11 of the flying object supported by the support device 200, and the on-off valve 150 closes the flow path, the servo valve 140, the position and speed of the piston 112 can be controlled, the other end of the piston rod 113 can be moved toward the landing gear 10, and when the on-off valve 150 opens the flow path, the piston 112 is pushed by the first pressure P1. Moves from the first chamber H1 side to the second chamber h2 side, the other end of the piston rod 113 is retracted from the landing gear 10, and the landing gear 10 can be tested.
Further, the force that pushes the piston 112 by the second pressure P2 is greater than the force that pushes the piston 112 by the first pressure P1, and the servo valve 140 adjusts the flow rate of the hydraulic oil when the on-off valve 150 closes the flow path, and the piston The rod 113 is moved to the landing gear 10 side, and the opening / closing valve 150 opens the hydraulic fluid flow path at a predetermined timing. Therefore, the piston rod 113 pushes the landing gear 10 at the predetermined timing, and stops pressing at the predetermined timing. The rod 113 is retracted to prevent interference between the landing gear 10 and the piston rod 113, and the transient motion of the landing gear 10 can be tested.
Further, since the predetermined timing is one of the timing when the moving distance of the piston rod 113 exceeds a predetermined value or the thrust of the piston rod 113 exceeds the predetermined value, the landing gear 10 is set to the predetermined timing. It is possible to remove the initial displacement or the initial load when the initial displacement of the value is applied or after the initial load of the predetermined value is applied to the landing gear 10.
In addition, the portion of the rod end 114 that contacts the load receiving jig has a hemispherical shape, and the portion of the load receiving jig 170 that contacts the rod end 114 has a planar shape. The jig 170 makes a so-called point contact and does not cause an unnecessary load on the landing gear.

The present invention is not limited to the embodiments described above, and various modifications can be made without departing from the scope of the invention.
Although the hydraulic equipment and the load equipment have been described as examples in the landing gear test apparatus, the present invention is not limited to this, and the present invention is not limited to this, and can also be used for equipment that applies a load to other equipment and test equipment that tests other equipment. .

It is a line system diagram of the hydraulic equipment concerning the embodiment of the present invention. 1 is a conceptual diagram of a test apparatus according to an embodiment of the present invention. 1 is a front view of a test apparatus according to an embodiment of the present invention. 1 is a plan view of a test apparatus according to an embodiment of the present invention. It is the sequence diagram 1 of the test apparatus which concerns on embodiment of this invention. FIG. 3 is a second sequence diagram of the test apparatus according to the embodiment of the present invention.

Explanation of symbols

H1 1st chamber H2 2nd chamber P1 1st pressure P2 2nd pressure P Power port T Tank port S Circumferential surface 10 Aircraft landing gear 11 Wheel 12 Wheel shaft 13 Leg structure 13a Upper leg column 13b Lower leg column 13c Storage mechanism 100 Hydraulic equipment 110 Hydraulic cylinder 111 Cylinder body 112 Piston 113 Piston rod 114 Rod end 115 Linear sensor 120 Gas chamber
121 Gas cylinder 122 Gas communication pipe 130 Hydraulic source 140 Servo valve 141 Servo driver 142 Power connection pipe 150 Open / close valve 151 Tank connection pipe 160 Load cell 170 Load receiving jig 200 Support device 210 Frame 220 Lifting mechanism 221 Air cylinder 222 Lifting hydraulic cylinder 223 Mass travel 230 Cargo 240 Leg mounting jig 300 Rotating drum 400 Measuring device 410 Steering angle measuring device 411 Laser displacement meter 412 Reflecting mirror 420 Rolling angle measuring device 422 Laser displacement meter 423 Reflecting mirror

Claims (5)

Hydraulic equipment operated by hydraulic oil,
A hydraulic cylinder having a cylinder body having a cavity inside, and a piston that divides the cavity into a first chamber and a second chamber and is guided movably in the cylinder body;
A gas chamber for storing a gas having a first pressure;
A hydraulic pressure source having a power port for discharging hydraulic oil having a second pressure and a tank port communicating with the tank;
A servo valve with adjustable hydraulic oil flow rate,
An on-off valve capable of opening and closing the hydraulic oil flow path;
With
The gas chamber and the first chamber communicate with each other;
The second chamber and the tank port communicate with each other via the on-off valve;
The second chamber and the power port communicate with each other via the servo valve;
Hydraulic equipment characterized by that. A load device that operates with hydraulic oil and applies a load to an object,
A cylinder main body having a hollow inside, a piston that is movably guided to the cylinder main body, which is divided into a first chamber and a second chamber, one end connected to the piston, and the other end protruding from the cylinder main body Hydraulic source having a hydraulic cylinder having a piston rod, a gas chamber for storing a gas having a first pressure, a power port for discharging hydraulic oil having a second pressure, and a tank port communicating with the tank A servo valve capable of adjusting the flow rate of hydraulic oil, and an on-off valve capable of opening and closing the hydraulic oil flow path, wherein the gas chamber and the first chamber are communicated with each other, and the second chamber and the A hydraulic device in which a tank port communicates with the on-off valve, and the second chamber communicates with the power port through the servo valve;
A support device for supporting an object;
With
Pressing the other end of the piston rod against the object;
Load equipment characterized by that. A landing gear test device that is actuated by hydraulic oil and applies a load to the landing gear of the flying object,
A cylinder main body having a hollow inside, a piston that is movably guided to the cylinder main body, which is divided into a first chamber and a second chamber, one end connected to the piston, and the other end protruding from the cylinder main body Hydraulic source having a hydraulic cylinder having a piston rod, a gas chamber for storing a gas having a first pressure, a power port for discharging hydraulic oil having a second pressure, and a tank port communicating with the tank A servo valve capable of adjusting the flow rate of hydraulic oil, and an on-off valve capable of opening and closing the hydraulic oil flow path, wherein the gas chamber and the first chamber are communicated with each other, and the second chamber and the A hydraulic device in which a tank port communicates with the on-off valve, and the second chamber communicates with the power port through the servo valve;
A support device for supporting the landing gear;
A rotating drum having an outer peripheral surface that simulates landing on the landing gear wheel;
With
Pressing the other end of the piston rod against the wheel axle of the landing gear wheel;
The landing gear test equipment characterized by that. The force pushing the piston by the second pressure is greater than the force pushing the piston by the first pressure;
When the on-off valve closes the flow path, the servo valve adjusts the flow rate of hydraulic oil and moves the piston rod toward the wheel shaft,
The on-off valve opens the hydraulic fluid flow path at a predetermined timing;
The landing gear test apparatus according to claim 3, wherein The predetermined timing is one timing when the moving distance of the piston rod exceeds a predetermined value or when the thrust of the piston rod exceeds a predetermined value.
The landing gear test apparatus according to claim 4, wherein

Images