Test method for simulating the charging and discharging of aircraft hydraulic accumulators

Abstract

The present invention discloses a method for simulating the charging and discharging of an aircraft hydraulic accumulator, which is not affected by the operator, provides reliable test data, and has high measurement efficiency. The present invention is achieved through the following technical solutions: gas is injected into the charging and discharging control cylinder through a nozzle connected to a vent shaft, a push rod forms an airtight ring seal through a sealing ring at the upper end of the charging and discharging control cylinder, and the charging gas is transmitted to the pressure gauge and the accumulator check valve through the charging and discharging control cylinder. The air pressure pushes open the push rod of the check valve, the cone seal of the check valve opens, and the charging gas enters the accumulator air chamber, forming a pressure difference with the accumulator liquid chamber, driving the piston in the accumulator to move; when deflation occurs, the nozzle is separated from the air pipe, and the handle is rotated to drive the push rod downward. After the lower end face of the downwardly moving push rod contacts the upper end face of the push rod of the accumulator check valve, the push rod continues to move downward, breaking through the cone seal of the check valve. The gas in the air chamber uses the pressure difference to pass through the inside of the charging and discharging control cylinder and be discharged through the nozzle, completing the charging and discharging test.

Description

Technical Field

[0001] The present invention relates to a test device for charging and deflating accumulator products, which is in the technical field of hydraulic accumulator charging and pressure measuring devices. The device is used to charge and deflat the accumulator air cavity, thereby causing the piston to reciprocate, so as to simulate the actual movement of the accumulator product on an aircraft and achieve the test purpose. Background Art

[0002] Accumulators are common devices in many engineering fields. As the name suggests, they are used to store energy. Through accumulators, energy can be stored and sometimes used to convert small, continuous bursts of energy into short bursts of energy, or vice versa. Accumulators can be electric, fluid, or mechanical, and can take the form of rechargeable batteries, hydraulic accumulators, capacitors, compressors, steam accumulators, and many other types. Accumulators are categorized by their loading method, including gravity accumulators, spring accumulators, and gas-charged accumulators. Hydraulic accumulators are energy storage devices used in hydraulic starting systems. Some hydraulic system actuators operate intermittently, with a very short total operating time. Other hydraulic systems, while not intermittent, have widely varying speeds within a single operating cycle (or stroke). Some systems require that the actuator continue to perform its required function in the event of a pump failure or power outage (a sudden interruption of the oil supply to the actuator). For example, for safety reasons, the piston rod of a hydraulic cylinder must retract within the cylinder. In such cases, an accumulator of appropriate capacity is required as an emergency power source. Sudden changes in the direction of a reversing valve, sudden stops in a hydraulic pump, sudden stops in actuator movement, or even the need for emergency braking can cause sudden changes in the fluid flow within the pipeline, generating pressure surges (oil shocks). Even with safety valves in the system, short-term pressure surges and shocks are unavoidable. These pressure surges often cause failure or even damage to instruments, components, and seals in the system, or rupture pipelines. Furthermore, they can produce noticeable system vibration. Installing an accumulator before the control valve or hydraulic cylinder shock source can absorb and mitigate these shocks. Pump flow fluctuations can cause pressure pulsations, resulting in uneven actuator movement and vibration and noise. A pneumatic strain energy accumulator is an energy storage and supply device that expands and contracts at a relatively constant pressure during inflation and deflation. During inflation, energy is stored in the form of strain energy in the stretched rubber material and compressed air energy. The deflation process is the reverse of the inflation process. During inflation, the pneumatic strain energy accumulator undergoes significant geometric deformation. The factors that primarily influence energy storage are the strain in the rubber material and the pressure of the gas within the device. Leakage or insufficient pressure in the air-charged accumulator will have a great impact on the hydraulic system and is a hydraulic system failure mode that many people may overlook.When an accumulator is used as an auxiliary pressure source, if leakage causes insufficient charge pressure, the accumulator will be unable to provide sufficient hydraulic energy, resulting in frequent starts and stops of the hydraulic pump motor, failing to save energy, and even risking the actuator not receiving the required hydraulic energy in a timely manner. When an accumulator is used as an emergency power source, if leakage causes insufficient charge pressure, the accumulator will not be able to provide sufficient energy to return the actuator to its original position. When an accumulator is used to absorb hydraulic shock, if leakage causes insufficient charge pressure, the accumulator will not have enough compressible gas to absorb the hydraulic shock. When a hydraulic shock occurs, the energy it can absorb is limited, potentially causing damage to hydraulic components. An accumulator, used to store hydraulic energy in a hydraulic system, is a hydraulic accessory that absorbs pressure pulsations and shock pressure. This accumulator is a chamber that stores pressure. The high-pressure oil discharged from the orifice serves as the starting power for the control system. For example, when the air pressure in an air shock absorber is insufficient, it replenishes the air pressure to maintain normal pressure and height. The physical process of the accumulator's action is as follows: the gas generator continuously generates high-pressure gas to push the piston, compressing the hydraulic oil at the other end of the piston. Initially, only the throttle valve is open, and oil flows out of the throttle hole. As the piston's speed increases, the oil pressure gradually increases. When it reaches the opening pressure of the relief valve, the relief valve opens, and oil flows out of both the throttle hole and the overflow hole simultaneously. Due to the increase in the hydraulic oil outlet area, its outflow speed decreases, thereby reducing the oil pressure. In this way, the air pressure, oil pressure, and piston speed are in a state of dynamic equilibrium until the piston moves to the bottom of the cavity and the oil pressure suddenly drops to zero. If the gas generator has not burned out when the piston moves to the bottom of the cavity, the air pressure will continue to rise until it reaches its extreme value when it burns out. Otherwise, the air pressure will continue to drop.

[0003] A hydraulic accumulator is a device that stores the potential energy of an incompressible liquid and maintains pressure with the help of an external power source. It is widely used in mechanical oil supply systems and hydraulic control systems. Its main functions are to temporarily store hydraulic energy and release it when needed; and to absorb the hydraulic shock generated by pressure changes in the hydraulic system. There are various types of accumulators used in hydraulic control systems, including piston accumulators, bladder accumulators, diaphragm accumulators, and gravity- and spring-loaded accumulators. The core component and power source of piston accumulators is a gas generator. This accumulator's function is to provide a certain amount of power to the control system before the hydraulic pump operates normally, allowing it to control turns and adjust course. One of the main tasks of a hydraulic accumulator is to carry a specified volume of pressurized fluid in the hydraulic system and return it to the system where it is needed. Any hydraulic system is powered by a pump configured to provide a predetermined continuous power supply. A more powerful pump can pump hydraulic fluid faster at a given pressure, but also requires more energy. Hydraulic accumulators also perform a variety of functions, including energy storage, shock, vibration, and pulsation damping, energy recovery, and volumetric flow compensation.

[0004] The hydraulic power system on an aircraft has become a critical component of modern aircraft. This system generally includes an oil pump, oil tank, pressure regulating valve, accumulator, oil filter, and cooling system. Modern civil airliners typically have three isolated and independent hydraulic power systems. This system utilizes the hydraulic energy provided by the hydraulic power system to achieve operational tasks. By appropriately combining actuators and control and regulating elements, various forms of motion or sequences of motion can be generated. Air entering the hydraulic system can severely impact its performance. Accumulators, a key component providing hydraulic power to the aircraft's hydraulic system, maintain stable pressure throughout the system. Hydraulic system fault testing is a key component of civil aircraft airworthiness certification. Accumulators temporarily store and provide timely hydraulic energy in the aircraft's hydraulic system, playing a vital role in ensuring the proper and reliable operation of the hydraulic system and ultimately flight safety. Accumulators in aircraft hydraulic systems are used to assist the pump in supplying pressure to the system when flow and pressure demands are high, and to mitigate pressure fluctuations during normal operation. 4. Store energy and supply pressure to critical aircraft components (such as brakes) when necessary. 5. Accumulate pressure to replenish oil lost in the hydraulic tank due to evaporation and leakage. During flight, the ambient temperature fluctuates significantly, causing the volume of the accumulator's internal air chamber to fluctuate significantly with temperature, resulting in changes in pressure. Before takeoff, when the aircraft is on the ground, the hydraulic energy system charges the accumulator, maintaining the internal pressure of the accumulator consistent with the system pressure. Increased fluid volume: During descent and landing, the ambient temperature rises, causing the gas to expand. Since the oil pump's flow rate is zero when pressure is restored, and the hydraulic accumulator pressure has dropped to 1800 psi, the system pressure is below 1800 psi. When the engine-driven pump (EDP) restores pressure, it must gradually recharge the system and accumulator. However, due to the presence of a check valve, excess oil in the accumulator cannot be discharged, causing internal pressure to increase, leading to problems such as overpressure, which can affect the normal and safe operation of the aircraft.

[0005] With the development of modern aviation, aircraft structures have become increasingly complex, and the requirements for aircraft components are becoming increasingly stringent. Simultaneously, to ensure the quality and assembly requirements of each component, more and more aircraft components are imposing strict requirements on the testing process and procedures for hydraulic accumulators. The testing process has strict step specifications and must be carried out according to these procedures. The pass / failure of the hydraulic accumulator charging and deflating test results is directly related to the overall performance and service life of the component. Since the accumulator itself does not have the automatic filling and deflating function of the air chamber during the test procedure, a test device is required to perform this step. This requires a test device that is simple to install and easy to operate, enabling accumulator products to quickly charge and deflate to meet testing requirements. Summary of the Invention

[0006] In order to enable accumulator products to have rapid charging and discharging functions to meet test requirements, the task of the present invention is to provide a simulated aircraft hydraulic accumulator charging and discharging test method that is simple to install, convenient and safe to operate, unaffected by the operator, with reliable test data, high measurement efficiency, and easy maintenance.

[0007] The technical solution adopted by the present invention to solve the technical problem is: a method for simulating the charging and discharging test of an aircraft hydraulic accumulator, which has the following technical features: preparing a charging and discharging test device for an accumulator product with a handle 1, the handle 1 is inserted into the push rod 2 of the charging and discharging control tube 3 to connect to the measured medium equipment, the push rod 2 has a stepped shaft that gradually changes from large to small and extends out of the cylinder through the corresponding matching charging and discharging control tube 3 and is movably connected or inserted into the one-way valve joint 12 of the accumulator; the pressure measuring joint 9 is radially connected to the air pipe through the nozzle 10 circumferentially welded at the bottom of the first section of the charging and discharging control tube 3, and the gas is injected into the charging and discharging control tube 3 through the nozzle 10 connected to the ventilation shaft 5, and the push rod 2 forms an airtight rubber ring seal through the sealing ring 4 at the upper end of the charging and discharging control tube 3, and the inflation gas can only be transmitted to the pressure gauge and the accumulator through the charging and discharging control tube 3. The one-way valve 13 pushes open the one-way valve push rod 14 through air pressure, so that the one-way valve cone seal 15 is in an open state, and the inflation gas enters the accumulator air chamber 16, and the simulated gas enters the fluid chamber and forms a pressure difference with the accumulator liquid chamber 17, driving the piston 18 in the accumulator to move, and the pressure gauge records the air pressure value at all times; when deflating, the pressure gauge is always connected to the pressure measuring joint 9, the nozzle 10 is separated from the air pipe, and the rotating handle 1 drives the push rod 2 to move downward. After the lower end face of the downward-moving push rod 2 contacts the upper end face of the accumulator one-way valve push rod 14, it continues to drive the one-way valve push rod 14 to move downward, breaking through the one-way valve cone seal 15, and the gas in the accumulator air chamber 16 uses the pressure difference to pass through the inside of the overcharge and discharge control cylinder 3 and be discharged through the nozzle 10. The pressure gauge records the pressure value at all times until the gas is completely discharged and the indication number is 0, completing the charging and discharging test.

[0008] The present invention has the following beneficial effects:

[0009] In order to overcome the load, it is necessary to apply sufficiently large pressure to the oil. The present invention adopts a stepped shaft with a gradual change from large to small push rod 2, which extends out of the cylinder through the corresponding charging and discharging control cylinder 3 and is movably connected or inserted into the end-to-end one-way valve joint 12 of the accumulator; the pressure measuring joint 9 is radially connected to the air pipe through the nozzle 10 circumferentially welded at the bottom of the first section of the charging and discharging control cylinder 3, and the gas is injected into the charging and discharging control cylinder 3 through the nozzle 10 connected to the ventilation shaft 5. The simulated aircraft hydraulic accumulator charging and discharging test method composed of the above-mentioned methods has a simple structure and is easy and safe to install: during the charging and discharging process, it is only necessary to connect the special test equipment to each joint and rotate the handle 1 to meet the test requirements. A push rod 2 with a handle 1 that can be inserted into the charge and discharge control cylinder 3 is used to connect the measured medium equipment and the pressure measuring joint 9 of the pressure gauge, which has strong versatility; the inflation gas can only be transmitted to the pressure gauge and the accumulator check valve 13 through the charge and discharge control cylinder 3, and the check valve push rod 14 is opened by the air pressure, so that the check valve cone surface seal 15 is opened, which can ensure the long-term and stable supply of the high-pressure source.

[0010] The present invention simulates the hydraulic pressure loss state and the servo actuator distributor failure state to ensure the initial pressure of the accumulator and other matters such as leakage inspection. Gas is injected into the charging and discharging control cylinder 3 through the nozzle 10 connected to the ventilation shaft 5. The push rod 2 forms an airtight rubber ring seal through the sealing ring 4 at the upper end of the charging and discharging control cylinder 3. The inflation gas can only be transmitted to the pressure gauge and the accumulator one-way valve 13 through the charging and discharging control cylinder 3. The one-way valve push rod 14 is pushed open by air pressure. The three sealing methods of rubber ring sealing, cone sealing and end face sealing are used to ensure that there is no leakage in the test, effectively protect the pressure test device, and ensure the confirmation of the test data.

[0011] The present invention accommodates check valves of varying sizes for various accumulator products. A push rod 2, with a stepped shaft that gradually transitions from large to small, extends through a corresponding charge / discharge control cylinder 3 and is movably connected or inserted into the accumulator's check valve connector 12. This design simplifies manufacturing. Simply replacing the tightening nut 7 and charge / discharge control cylinder 3 allows for the charging and discharging of various accumulator products. This simple operation is unaffected by the operator.

[0012] The present invention combines the actual conditions of the aircraft and uses air pressure to push open the one-way valve push rod 14, so that the one-way valve cone seal 15 is in an open state. The inflation gas enters the accumulator air chamber 16, forming a pressure difference with the accumulator liquid chamber 17, driving the piston 18 in the accumulator to move, and the pressure gauge constantly records the air pressure value. Under the same simulated temperature environment, the heat exchange rate between the accumulator and the external environment and the rate of pressure increase are effectively reduced, thus avoiding accumulator overpressure. When deflation occurs, the rotating handle 1 drives the push rod 2 to move downward, breaking through the one-way valve cone seal 15. The gas in the accumulator air chamber 16 uses the pressure difference to pass through the inside of the overcharge and discharge control cylinder 3 and be discharged through the nozzle 10, reducing the degree of temperature change inside the accumulator fluid chamber. The pressure gauge constantly records the pressure value until the gas is completely discharged, which can effectively reduce the accumulator overpressure: preliminary verification through simulation means shows that the test data is reliable, accurate, and the measurement efficiency is high. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 1. It is a test schematic diagram of a method for simulating the charging and discharging of an aircraft hydraulic accumulator according to the present invention;

[0014] Figure 2 yes Figure 1 Removed cross-sectional view of AA;

[0015] Figure 3 It is a partial schematic diagram of the accumulator under test.

[0016] In the figure: 1 is a handle, 2 is a push rod, 3 is a charge and discharge control cylinder, 4 is a sealing ring, 5 is a vent shaft, 6 is a copper washer, 7 is a tightening nut, 8 is a steel ball plate, 9 is a pressure measuring joint, 10 is a nozzle, 11 is a screw, 12 is a one-way valve joint, 13 is a one-way valve, 14 is a one-way valve push rod, 15 is a one-way valve cone seal, 16 is an accumulator air chamber, 17 is an accumulator liquid chamber, and 18 is a piston in the accumulator. DETAILED DESCRIPTION

[0017] See Figure 1 、 Figure 2. According to the present invention, a pressure accumulator product charging and discharging test device with a handle 1 is prepared, the handle 1 is inserted into the top rod 2 of the charging and discharging control cylinder 3 to connect to the measured medium equipment, the top rod 2 has a stepped shaft that gradually changes from large to small and extends out of the cylinder through the corresponding matching charging and discharging control cylinder 3 to be movably connected or inserted into the one-way valve joint 12 of the pressure accumulator; the pressure measuring joint 9 is radially connected to the air pipe through the nozzle 10 circumferentially welded at the bottom of the first section of the charging and discharging control cylinder 3, and the gas is injected into the charging and discharging control cylinder 3 through the nozzle 10 connected to the ventilation shaft 5, and the top rod 2 forms an airtight rubber ring seal through the sealing ring 4 at the upper end of the charging and discharging control cylinder 3, and the inflation gas can only be transmitted to the pressure gauge and the accumulator one-way valve 13 through the charging and discharging control cylinder 3, and the one-way valve top rod is pushed open by the air pressure. 14, so that the one-way valve cone seal 15 is in the open state, the inflation gas enters the accumulator air chamber 16, the simulated gas enters the fluid chamber and forms a pressure difference with the accumulator liquid chamber 17, which drives the piston 18 in the accumulator to move, and the pressure gauge records the air pressure value at all times; when deflating, the pressure gauge is always connected to the pressure measuring joint 9, the nozzle 10 is separated from the air pipe, and the rotating handle 1 drives the push rod 2 to move downward. After the lower end face of the downward-moving push rod 2 contacts the upper end face of the accumulator one-way valve push rod 14, it continues to drive the one-way valve push rod 14 to move downward, breaking through the one-way valve cone seal 15. The gas in the air chamber uses the pressure difference to pass through the inside of the overcharge and discharge control cylinder 3 and be discharged through the nozzle 10. The pressure gauge records the pressure value at all times until the gas is completely discharged and the number indicated is 0, completing the inflation and discharge test.

[0018] In the preferred embodiment described below, the vent shaft 5 is circumferentially welded to the outer circle of the charge and discharge control cylinder 3 through the copper washer 6 and the bottom restraint disk assembled in the cylinder of the pressure gauge pressure measuring joint 9, and is radially connected to the nozzle 10 circumferentially welded on the diameter end of the charge and discharge control cylinder 3 through the necked shaft cylinder.

[0019] The accumulator product charging and discharging test device comprises: a charging and discharging control cylinder 3 with a handle 1 inserted into the measured medium device, a sealing ring 4 of the charging and discharging control cylinder 3 ring sealing the charging and discharging control cylinder 2, a vent shaft 5 with a pressure measuring joint 9 radially passing through the cylinder body of the charging and discharging control cylinder 3 and a nozzle 10 connected to the air pipe, a step cylinder screw nut 7 at the lower part of the charging and discharging control cylinder 3 through a steel ball plate 8 in a step hole, pushing the charging and discharging control cylinder 3 into a one-way valve joint, the step shaft of the charging and discharging control cylinder 3 gradually changing from large to small extending out of the cylinder body through the corresponding matching charging and discharging control cylinder 3, movably connected or inserted into the one-way valve joint 12 of the accumulator, and the rotation of the steel ball plate 8 is controlled by a screw 11 corresponding to the steel ball plate 8; gas is injected into the charging and discharging control cylinder (3) through the nozzle 10 connected to the vent shaft 5, and the accumulator air cavity 16 utilizes the internal gas pressure difference to pass through the inside of the charging and discharging control cylinder 3 and be discharged through the nozzle 10. The lower step tube of the charge and discharge control tube 3 is screwed to the tightening nut 7, and the steel ball plate 8 in the step hole of the tightening nut 7 is used to push the push rod 2 into the one-way valve joint 12. The rotation of the steel ball plate 8 is controlled by the screw 11 corresponding to the steel ball plate 8.

[0020] The push rod 2 passes through the center hole in the charge and discharge control cylinder 3 and is connected through the internal thread of the charge and discharge control cylinder 3. A sealing ring 4 is formed in the middle to form an airtight rubber ring seal; then the tightening nut 7 is installed on the charge and discharge control cylinder 3, ensuring that the inner ring groove of the tightening nut 7 and the outer ring groove on the charge and discharge control cylinder 3 coincide with each other, and the steel ball is placed between the inner ring groove and the outer ring groove on the charge and discharge control cylinder 3 through the threaded hole on the tightening nut 7 to ensure that the steel ball slides without getting stuck, and then the screw 11 is rotated and screwed into the threaded hole on the tightening nut 7 to ensure that the steel balls on the steel ball plate 8 do not fall out.

[0021] The small end of the vent shaft 5 passes through the small inner hole in the pressure gauge joint 9 and is installed in the corresponding small hole on the charge and discharge control cylinder 3. The interface is welded along the circumference to ensure that there is no air leakage. Then the small end of the nozzle is installed in the corresponding small hole on the charge and discharge control cylinder 3. The interface is welded along the circumference to ensure that there is no air leakage. Finally, the handle 1 is passed through the small hole in the middle of the top of the push rod 2 to complete the installation of the charging and discharging test device.

[0022] After completing the installation of the device, the test began. First, the tightening nut 7 and the accumulator product's one-way valve joint 12 were connected through the internal and external threads. The steel balls on the ball plate 8 rolled. The device itself remained stationary. Only by rotating the tightening nut 7 and tightening the threads, the outer conical surface at the bottom of the charge and discharge control cylinder 3 and the inner conical surface of the one-way valve joint 12 were fully in contact, forming a conical seal to ensure no air leakage. Then, the pressure gauge was connected through the pressure gauge pressure measuring joint 9 and tightened completely. The internal copper washer 6 was deformed to form an end face seal to ensure no air leakage.

[0023] When the test device is inflated, the external thread of the nozzle 10 is connected with the internal thread of the trachea, and the external conical surface of the nozzle 10 is completely in contact with the inner conical surface of the trachea, forming a conical seal to ensure that there is no leakage. The inflated gas enters the inner hole of the charge and discharge control cylinder 3 through the inner hole of the upper end of the charge and discharge control cylinder 3 and the push rod 2 through the sealing ring 4 to form a rubber ring seal. The gas cannot pass through here and can only enter the pressure gauge through the inner hole of the vent shaft 5 and enter the accumulator check valve 13 through the inner hole of the lower end of the charge and discharge control cylinder 3. The air pressure pushes open the check valve push rod 14, the check valve cone seal 15 is opened, and the gas enters the accumulator air chamber 16, forming a pressure difference with the accumulator liquid chamber 17, driving the piston 18 in the accumulator to move, and the pressure gauge records the air pressure value at all times. After the inflation is completed, just release the trachea connected to the nozzle 10. Using the pressure difference, the gas in the accumulator air chamber 16 makes the check valve cone seal 15 contact again to form a seal.

[0024] When the test device is deflated, the nozzle 10 is not connected to the air pipe, and the handle 1 is rotated downward, driving the push rod 2 to rotate downward. The lower end face of the push rod 2 contacts the push rod 14 of the product's one-way valve, driving the accumulator's one-way valve push rod 14 downward, and the one-way valve cone seal 15 is opened. By utilizing the pressure difference, the gas in the accumulator air chamber 16 passes through the inner hole of the charge and discharge control cylinder 3, and is discharged outward through the inner hole of the vent shaft 5 and the inner hole of the nozzle 10. The pressure gauge records the air pressure value. When the gas is completely discharged and the pressure display shows 0, the test is completed.

[0025] See Figure 3 The accumulator charging and discharging test is carried out according to the following steps:

[0026] 1. The test device injects aviation hydraulic oil into the accumulator liquid chamber 17. The fluid enters the inlet of the accumulator's one-way valve, which is sealed by the cone surface. The pressure of the injected fluid is higher than the pre-charged pressure. The hydraulic fluid is pressed into the piston. The fluid enters the accumulator liquid chamber 17 and compresses the gas at the same time, exerting a steady force on the fluid. When the accumulator fluid pressure is lower than the gas chamber pressure, the gas chamber pressure decreases through the inlet fluid. As the piston speed increases, the oil pressure gradually increases. The piston is at the extreme position inlet, pushing the stored fluid back into the system.

[0027] 2. The test device inflates the accumulator air chamber 16, directly pushing the liquid with gas to increase the liquid's compression rate. The piston moves toward the liquid chamber, absorbing the hydraulic shock generated by the hydraulic system when the pressure changes. The air pressure continues to rise until it reaches the extreme value, and a certain amount of oil is discharged. The pressure value is recorded by the pressure gauge pressure connector 9;

[0028] 3. The test device deflates the accumulator air chamber 16 until it is completely emptied;

[0029] Through the above steps, the movement of the accumulator product on the aircraft is simulated to determine whether it is qualified.

[0030] Without paying any creative work, the present invention can also obtain other technical solutions based on the above embodiments, and equivalent changes made within the scope of protection of the present invention should fall within the scope of protection of the present invention and belong to the scope of protection of the present invention.

Claims

1. A method for simulating the charging and discharging of an aircraft hydraulic accumulator, having the following technical features: preparing a charging and discharging test device for an accumulator product with a handle (1), wherein the handle (1) is inserted into the push rod (2) of the charging and discharging control cylinder (3) to connect to the measured medium device, and the push rod (2) has a stepped shaft that gradually changes from large to small and extends out of the cylinder through the corresponding matching charging and discharging control cylinder (3) to be movably connected or inserted into the one-way valve joint (12) of the accumulator; the pressure measuring joint (9) is radially connected to the air pipe through the nozzle (10) circumferentially welded at the bottom of the first section of the charging and discharging control cylinder (3), and the gas is injected into the charging and discharging control cylinder (3) through the nozzle (10) connected to the ventilation shaft (5); the push rod (2) forms an airtight rubber ring seal through the sealing ring (4) at the upper end of the charging and discharging control cylinder (3), and the inflation gas can only be transmitted to the pressure gauge and the accumulator one-way valve (12) through the charging and discharging control cylinder (3). 3), the one-way valve push rod (14) is opened by air pressure, so that the one-way valve cone seal (15) is in an open state, and the inflation gas enters the accumulator air chamber (16), and the simulated gas enters the fluid chamber to form a pressure difference with the accumulator liquid chamber (17), driving the piston (18) in the accumulator to move, and the pressure gauge records the air pressure value at all times; when deflating, the pressure gauge is always connected to the pressure measuring joint (9), the nozzle (10) is separated from the air pipe, and the rotating handle (1) drives the push rod (2) to move downward. After the lower end surface of the downwardly moved push rod (2) contacts the upper end surface of the accumulator one-way valve push rod (14), it continues to drive the one-way valve push rod (14) to move downward, breaking through the one-way valve cone seal (15), and the gas in the accumulator air chamber (16) is discharged through the nozzle (10) by using the pressure difference, through the inside of the overcharge and discharge control cylinder (3), and the pressure gauge records the pressure value at all times until the gas is completely discharged, completing the inflation and deflation test.

2. The method for simulating the charging and discharging of an aircraft hydraulic accumulator according to claim 1, characterized in that: The vent shaft (5) is circumferentially welded to the outer circle of the charge and discharge control cylinder (3) through the copper washer (6) and the bottom restraining disk assembled in the cylinder of the pressure gauge pressure measuring joint (9), and is radially connected to the nozzle (10) circumferentially welded on the diameter end of the charge and discharge control cylinder (3) through the necked shaft cylinder.

3. The method for simulating the charging and discharging of an aircraft hydraulic accumulator according to claim 1, wherein: The lower step tube of the charge and discharge control tube (3) is screwed to the tightening nut (7) and pushes the push rod (2) into the one-way valve joint through the steel ball plate (8) in the step hole of the tightening nut (7). The rotation of the steel ball plate (8) is controlled by the screw (11) corresponding to the steel ball plate (8).

4. The method for simulating the charging and discharging of an aircraft hydraulic accumulator according to claim 1, wherein: The push rod (2) passes through the center hole in the charge and discharge control cylinder (3) and is connected through the internal thread of the charge and discharge control cylinder (3). A sealing ring (4) is formed in the middle to ensure that there is no air leakage. Then, the tightening nut (7) is installed on the charge and discharge control cylinder (3). After ensuring that the inner ring groove of the tightening nut (7) and the outer ring groove on the charge and discharge control cylinder (3) overlap, the steel ball is placed between the inner ring groove and the outer ring groove on the charge and discharge control cylinder (3) through the threaded hole on the tightening nut (7) to ensure that the steel ball slides without getting stuck. Then, the screw (11) is rotated and screwed into the threaded hole on the tightening nut (7) to ensure that the steel ball on the steel ball plate (8) does not fall out.

5. The method for simulating the charging and discharging of an aircraft hydraulic accumulator according to claim 1, wherein: The small end of the vent shaft (5) passes through the small inner hole in the pressure gauge pressure measuring joint (9), is installed in the corresponding small hole on the charge and discharge control cylinder (3), and the interface is welded along the circumference to ensure that there is no air leakage. Then, the small end of the nozzle (10) is installed in the corresponding small hole on the charge and discharge control cylinder (3), and the interface is welded along the circumference to ensure that there is no air leakage. Finally, the handle (1) is passed through the small hole in the middle of the top of the push rod (2), and the installation of the charge and discharge test device is completed.

6. The method for simulating the charging and discharging of an aircraft hydraulic accumulator according to claim 1, wherein: During the test, the tightening nut (7) and the one-way valve joint (12) of the accumulator product are first connected through the internal and external threads, and the steel balls on the steel ball plate (8) are rolled to ensure that the device itself does not move. Only by rotating the tightening nut (7), the threads are tightened, and the outer conical surface of the lower end of the charge and discharge control cylinder (3) and the inner conical surface of the one-way valve joint are completely in contact, forming an airtight conical surface seal. Then, the pressure gauge is connected through the pressure measuring joint (9) and fully tightened, and the internal copper gasket (6) is deformed to form an airtight end face seal.

7. The method for simulating the charging and discharging of an aircraft hydraulic accumulator according to claim 1, wherein: During inflation, the external thread of the nozzle (10) is connected to the internal thread of the trachea, and the external conical surface of the nozzle and the internal conical surface of the trachea are in full contact, forming an airtight conical seal. The inflation gas enters the inner hole of the charge and discharge control cylinder (3) through the inner hole of the nozzle (10). The upper inner hole of the charge and discharge control cylinder (3) and the push rod (2) form a seal through the sealing ring (4) so that the gas cannot pass through the rubber ring. The gas can only enter the pressure gauge through the inner hole of the vent shaft (5) and enter the pressure accumulator through the inner hole of the lower end of the charge and discharge control cylinder (3). The one-way valve is opened, and the air pressure pushes open the one-way valve push rod (14), and the one-way valve cone seal (15) is opened. The gas enters the accumulator air chamber (16), forms a pressure difference with the accumulator liquid chamber (17), drives the piston (18) in the accumulator to move, and the pressure gauge records the air pressure value at all times. After the inflation is completed, the air pipe connected to the nozzle (10) is released. By utilizing the pressure difference, the gas in the accumulator air chamber (16) makes the one-way valve cone seal (15) contact again, forming a seal.

8. The method for simulating the charging and discharging of an aircraft hydraulic accumulator according to claim 1, wherein: When deflation occurs, the nozzle (10) is disconnected from the air pipe, and the handle (1) is rotated downward, driving the push rod (2) to rotate downward. The lowermost end surface of the push rod (2) contacts the push rod (14) of the product one-way valve, driving the push rod (14) of the accumulator one-way valve downward. The one-way valve cone seal (15) is opened. By utilizing the pressure difference, the gas in the accumulator air chamber (16) passes through the inner hole of the charge and discharge control cylinder (3), the inner hole of the vent shaft (5) and the inner hole of the nozzle (10) and is discharged to the outside. The pressure gauge records the air pressure value. When the gas is completely discharged and the pressure display number is 0, the test is completed.

9. The method for simulating the charging and discharging of an aircraft hydraulic accumulator according to claim 1, wherein: The charging and discharging test of accumulators shall be carried out in the following steps:

1. Inject aviation hydraulic oil into the accumulator liquid chamber (17). The fluid enters the inlet of the accumulator's one-way valve cone seal and is opened. The pressure of the fluid is higher than the pre-charged pressure. The hydraulic fluid is pressed into the piston. The fluid enters the accumulator liquid chamber (17) and compresses the gas at the same time, exerting a stable force on the fluid. When the accumulator fluid pressure is lower than the air chamber pressure, the air chamber pressure decreases through the inlet fluid. As the piston movement speed increases, the oil pressure gradually increases. The piston is at the extreme position inlet, pushing the stored fluid back into the system.

2. Inflate the accumulator air chamber (16) to directly push the liquid with the gas, increasing the compression rate of the liquid. The piston moves toward the accumulator liquid chamber (17) to absorb the hydraulic shock generated by the hydraulic system when the pressure changes. The air pressure continues to rise until it reaches the extreme value, and a certain amount of oil is discharged. The pressure value is recorded by the pressure gauge connector (9); 3. Deflate the accumulator air chamber until it is completely empty; Through the above steps, the movement of the accumulator product on the aircraft is simulated to determine whether it is qualified.

10. The method for simulating the charging and discharging of an aircraft hydraulic accumulator according to any one of claims 1 to 9, characterized in that: The device for testing the charging and discharging of accumulator products comprises: a charging and discharging control cylinder (3) inserted into the device for measuring the medium, a push rod (2) with a handle (1), a sealing ring (4) sealing the push rod (2) through the ring of the charging and discharging control cylinder (3), a vent shaft (5) with a pressure measuring joint (9) passing radially through the cylinder body of the charging and discharging control cylinder (3) and a nozzle (10) connected to the air pipe, a nut (7) screwed on the lower step cylinder of the charging and discharging control cylinder (3) through a steel ball disc (8) in the step hole, and pushing the push rod (2) to the single Into the valve joint, a stepped shaft of a push rod (2) gradually changes from large to small and extends out of the cylinder through a corresponding charge and discharge control cylinder (3), and is movably connected or inserted into a one-way valve joint (12) of the pressure accumulator. The rotation of the steel ball disk (8) is controlled by a screw (11) corresponding to the steel ball disk (8); gas is injected into the charge and discharge control cylinder (3) through a nozzle (10) connected to a vent shaft (5), and the accumulator air cavity (16) utilizes the internal gas pressure difference to pass through the inside of the charge and discharge control cylinder (3) and be discharged through the nozzle (10).

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