A process method and special test bed for air tightness and strength test of aircraft canopy

Abstract

The application belongs to the technical field of airplane debugging process, and particularly relates to a process method and a special test bench for an airplane canopy cover air tightness and strength test, comprising an oil tank, a manual pump, a reversing valve, a process actuating cylinder and a controller. The reversing valve is a three-position four-way reversing valve. Two oil ports on one side of the reversing valve are connected with the manual pump and the oil tank, and two oil ports on the other side of the reversing valve are connected with the inlet and outlet oil ports of the process actuating cylinder through hydraulic rubber pipes. The oil tank and the manual pump are connected with each other. The manual pump and the reversing valve are provided with a sensor. The sensor is electrically connected with the controller. The assembly process of the canopy cover pneumatic hydraulic system is successfully moved to the final assembly stage, and the process cross and repeated disassembly in the assembly and final assembly stages are completely avoided. The air tightness and strength test in the assembly stage can be independently and advancedly carried out, and the overall production cycle of the airplane is greatly compressed.

Description

Technical Field

[0001] This application belongs to the field of aircraft debugging technology, and specifically relates to a process method and a special test bench for testing the airtightness and strength of an aircraft cockpit canopy. Background Technology

[0002] The canopy systems of a certain series of aircraft have similar structures and working principles. In traditional repair or assembly processes, the canopy pneumatic-hydraulic system needs to be installed and debugged during the component assembly stage before the airtightness and strength tests of the cabin can be carried out.

[0003] However, this traditional process has the following drawbacks:

[0004] Process overlap and repetitive disassembly / reassembly: Due to the company's internal process setup, components such as actuators and manual opening mechanisms in the pneumatic and hydraulic system were consistently in short supply during the sub-assembly stage. Meanwhile, during the final assembly stage, when installing other components (such as oxygen cylinders and landing gear), it was necessary to disassemble some of the already installed hydraulic components, resulting in a large amount of repetitive work.

[0005] Cycle and cost issues: The above-mentioned issues lead to extended production cycles and waste a lot of human and material resources.

[0006] To solve the above problems, there is an urgent need for a process that can postpone the assembly process of the cockpit canopy pneumatic-hydraulic system while ensuring the safe conduct of cockpit airtightness and strength tests under these conditions. Summary of the Invention

[0007] To address the aforementioned issues, this application provides a process and dedicated test bench for testing the airtightness and strength of an aircraft cockpit canopy, thereby resolving the problem of high repetitiveness in the assembly of the cockpit canopy pneumatic-hydraulic system in the prior art.

[0008] The technical solution of this application is: a process method for testing the airtightness and strength of an aircraft cockpit canopy, including a fuel tank, a manual pump, a reversing valve, a process actuator, and a controller;

[0009] The reversing valve is a three-position four-way reversing valve. Two oil ports on one side of the reversing valve are connected to the manual pump and the oil tank, and two oil ports on the other side are connected to the inlet and outlet oil ports of the process actuator cylinder through hydraulic hoses.

[0010] The oil tank is connected to the manual pump, and the manual pump and the reversing valve are equipped with sensors, which are electrically connected to the controller.

[0011] Preferably, a locking valve is provided between the manual pump and the reversing valve, and between the oil tank and the reversing valve. The locking valve is a two-position two-way solenoid valve, and the locking valve is electrically connected to the controller.

[0012] A pressure gauge is also provided between the manual pump and the reversing valve. The pressure gauge is connected between the shut-off valve and the reversing valve through a three-way connector and a pressure gauge connector.

[0013] The oil tank is equipped with an oil filter at the bottom and a filter at the top.

[0014] Preferably, the sensor is one or more of a proximity switch, limit sensor, bubble sensor, displacement sensor, pressure sensor, or strain gauge.

[0015] Another technical solution of this application is: a process method for testing the airtightness and strength of an aircraft cockpit canopy, comprising the following steps:

[0016] The directional valve has a forward position, a closed position, and a reverse position. The controller drives the directional valve to move to the negative position and the forward position respectively, and controls the process actuator to complete the retraction-extension cycle until the gas in the oil circuit is discharged.

[0017] After the sensor detects that the hatch is closed, the controller controls the locking valve to close, cutting off the oil circuit;

[0018] The controller controls the piston rod of the process actuator to extend continuously according to the preset step pressure values, pressurizing the aircraft cabin in sequence, and monitors the rate of pressure drop in the cabin. If the pressure drop exceeds the threshold, an alarm is output.

[0019] The controller raises the pressure to a preset value and maintains it for a preset duration, while monitoring the structural deformation of the aircraft cabin through sensors.

[0020] Preferably, the preset step pressure values ​​are 9.8 kPa, 19.6 kPa, 29.4 kPa, and 39.2 kPa respectively. After each pressure level is reached, the pressure is stabilized for a preset time. The controller collects the pressure sensor signals in the cabin in real time and calculates the pressure drop rate per unit time.

[0021] Preferably, after completing all the step pressurization, the controller records the actual time it takes for the cabin pressure to drop from 39.2 kPa to 19.6 kPa. When the recorded actual time is greater than or equal to the preset qualified threshold, the airtightness test is deemed qualified.

[0022] Preferably, the controller raises the cabin pressure to 49 kPa and maintains it for 2 to 3 minutes, and collects deformation signals of the cabin canopy and surrounding structures in real time through displacement sensors or strain gauges.

[0023] Preferably, if the deformation is always below the maximum allowable deformation threshold and there is no permanent deformation after decompression, the controller outputs a strength test qualified signal; otherwise, it outputs an alarm signal.

[0024] The process method and dedicated test bench for testing the airtightness and strength of the aircraft cockpit canopy in this application have the following advantages:

[0025] Optimize the production process: The assembly process of the cockpit canopy pneumatic hydraulic system was successfully moved to the final assembly stage, completely avoiding the overlap of processes and repeated disassembly and assembly between the sub-assembly and final assembly stages.

[0026] Shortened production cycle: No longer constrained by the shortage of pneumatic and hydraulic system components, the airtightness and strength tests during the assembly stage can be carried out independently and in advance, significantly reducing the overall production cycle of the aircraft.

[0027] Ensuring test safety: Through a dedicated external test bench and automated hydraulic locking control, the cockpit canopy can be reliably locked even without installing the original system, completely eliminating the safety risk of "canopy jumping".

[0028] Cost savings: Reduces manpower waste and potential risk of parts damage caused by repeated disassembly and assembly. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the overall structure of this application.

[0030] 1. Oil filter; 2. Oil tank; 3. Filter; 4. Manual pump; 5. Locking valve; 6. T-connector; 7. Pressure gauge connector; 8. Pressure gauge; 9. Directional control valve; 10. Hydraulic hose; 11. Process actuator. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings. In the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The described embodiments are only some, not all, of the embodiments of this application. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application. The embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0032] The first aspect of this application provides a dedicated test bench for testing the airtightness and strength of an aircraft cockpit canopy, such as... Figure 1 It includes an oil tank 2, a manual pump 4, a reversing valve 9, a process actuator 11, and a controller.

[0033] The reversing valve 9 is a three-position four-way reversing valve. Two oil ports on one side of the reversing valve 9 are connected to the manual pump 4 and the oil tank 2, and two oil ports on the other side are connected to the inlet and outlet oil ports of the process actuator cylinder 11 through the hydraulic hose 10.

[0034] The oil tank 2 is connected to the manual pump 4. The manual pump 4 and the reversing valve 9 are equipped with sensors, which are electrically connected to the controller.

[0035] Based on the original actuator specifications of the canopy of this aircraft model, a process actuator 11, typically manufactured at a 1:1 scale, was selected. The inlet and outlet ports of this process actuator 11 were connected to the corresponding interfaces of a dedicated test bench (canopy control test bench) via hydraulic hoses. The dedicated test bench integrates: a manual pump 4, a reversing valve 9, a locking valve 5, and controllers for controlling the reversing valve 9 and the locking valve 5.

[0036] An external hydraulic test system is constructed by oil tank 2, manual pump 4, three-position four-way reversing valve 9, 1:1 process actuator 11, and controller. This system simulates the cockpit canopy opening and closing action without installing the original aircraft canopy pneumatic-hydraulic system, further enabling the hydraulic system assembly process to be moved downstream and improving efficiency. Standardized hydraulic connections and sensor electrical connections are used to ensure reliable test bench control and accurate signal acquisition, providing basic hardware support for airtightness and strength tests.

[0037] Preferably, a locking valve 5 is provided between the manual pump 4 and the reversing valve 9, and between the oil tank 2 and the reversing valve 9. The locking valve 5 is a two-position two-way solenoid valve, and the locking valve 5 is electrically connected to the controller.

[0038] A pressure gauge 8 is also provided between the manual pump 4 and the reversing valve 9. The pressure gauge 8 is connected between the shut-off valve 5 and the reversing valve 9 through a three-way connector 6 and a pressure gauge connector 7.

[0039] Oil filter 1 is connected to the bottom of oil tank 2, and filter 3 is installed on the top.

[0040] A two-position, two-way, electrically controllable shut-off valve 5 is installed in the critical oil circuit to achieve precise oil circuit opening and closing and hydraulic locking, preventing the cockpit canopy from opening accidentally during the test; a pressure gauge 8 is configured to facilitate on-site pressure monitoring and fault diagnosis; an oil filter 1 and a filter 3 are installed in the oil tank 2 to improve oil cleanliness, reduce the risk of oil circuit blockage and component wear, and improve the operational stability and service life of the test bench.

[0041] Preferably, the sensor is one or more of a proximity switch, limit sensor, bubble sensor, displacement sensor, pressure sensor, or strain gauge.

[0042] The second aspect of this application provides a process method for testing the airtightness and strength of an aircraft cockpit canopy, comprising the following steps:

[0043] Step 1: The reversing valve 9 has a positive position, a closed position and a reverse position. The controller drives the reversing valve 9 to move to the negative position and the positive position respectively, and controls the process actuator 11 to complete the retraction-extension cycle until the gas in the oil circuit is discharged.

[0044] Specifically:

[0045] The controller drives the reversing valve 9 to switch to the negative position and starts the manual pump 4 (or automatic pump) to supply pressure to the lower chamber of the process actuator cylinder 11, driving its piston rod to retract to the limit position. At this time, the controller controls the exhaust valve connected to the upper chamber to open, continuously supplying pressure until the cavitation rate in the hydraulic oil discharged from the upper chamber is lower than a preset threshold (for example, detected by an oil bubble sensor), and then closes the exhaust valve.

[0046] The controller drives the reversing valve 9 to switch to the forward position, supplying pressure to the upper chamber of the process actuator cylinder 11 and driving its piston rod to extend fully. At the same time, the controller controls the exhaust valve connected to the lower chamber to open, continuously supplying pressure until the lower chamber is completely vented.

[0047] Circulating exhaust command: The controller controls the reversing valve 9 to make the process actuator 11 complete at least 10 complete cycles of "extend-retract" action. In each cycle, the displacement stroke of the piston rod is fed back to the controller through the displacement sensor to ensure smooth action without jamming and complete system exhaust.

[0048] Step two: After the sensor detects that the hatch is closed, the controller controls the locking valve 5 to close, cutting off the oil circuit. Specifically:

[0049] After venting is completed, the process actuator 11 is installed at the corresponding mounting point on the aircraft canopy. The operator issues a "close canopy" command through the test bench panel, and the controller automatically controls the reversing valve 9 to slowly extend the process actuator 11, driving the canopy to close.

[0050] Once the canopy is fully closed (based on feedback from a proximity switch or limit sensor), the controller automatically sends a closing signal to the locking valve 5. This locking valve 5 is a normally closed two-position, two-way solenoid valve that cuts off the main oil circuit connecting the upper and lower chambers of the process actuator 11, placing the process actuator 11 in a hydraulically locked state. In this state, even if the upward thrust generated by the increased air pressure inside the cockpit cannot push the process actuator 11, thus physically preventing the canopy from opening.

[0051] Step three: The controller continuously extends the piston rod of the process actuator 11 according to the preset stepped pressure values, sequentially pressurizing the aircraft cabin and monitoring the rate of pressure drop within the cabin. If the pressure drop exceeds the threshold, an alarm is triggered. Specifically:

[0052] The controller receives signals from pressure sensors inside the cockpit. It sequentially outputs pressurization commands to the external air supply regulating valve according to preset stepped pressure values ​​(9.8 kPa, 19.6 kPa, 29.4 kPa, 39.2 kPa). Upon reaching each pressure level, the controller automatically closes the air supply valve and starts a timer to maintain the preset pressure stabilization time (e.g., 5 minutes). During the pressure stabilization period, the controller continuously monitors the pressure drop rate: if the pressure drop per unit time exceeds a preset threshold, a leak is detected, and a leak alarm and leak location indication (based on differential pressure or pressure holding methods) are output.

[0053] After the step pressurization is completed, the controller shuts off the air supply and records the actual depressurization time from 39.2 kPa to 19.6 kPa. If the actual depressurization time is greater than or equal to the preset qualified threshold (e.g., 10 minutes), the controller automatically outputs a "Airtightness Test Qualified" signal.

[0054] Step four: The controller raises the pressure to a preset value and maintains it for a preset duration, while monitoring the structural deformation of the aircraft cabin through sensors.

[0055] The controller automatically controls the reversing valve 9 to complete the oil circuit venting, hatch closure and hydraulic locking, avoiding human operation errors and improving test consistency; it automatically pressurizes according to step pressure and monitors leakage to achieve rapid quantitative detection of cabin airtightness; it increases and holds pressure and monitors deformation to complete cabin structural strength verification, and the whole test process is automated and safe.

[0056] Preferably, after the controller completes all the step pressurization, it records the actual time it takes for the cabin pressure to drop from 39.2 kPa to 19.6 kPa. When the recorded actual time is greater than or equal to the preset qualified threshold, the airtightness test is deemed qualified.

[0057] The judgment criteria are intuitive, quantitative, and uniform, avoiding human judgment bias, improving the reliability and comparability of airtightness test results, and facilitating standardized acceptance in batch assembly and repair scenarios.

[0058] Preferably, after the airtightness is deemed satisfactory, the controller outputs a pressurization command to increase the cabin pressure to 49 kPa and maintain it for a preset strength holding time (e.g., 2-3 minutes). During this period, the controller monitors the deformation of the canopy and surrounding structures using strain gauges or displacement sensors. If the deformation remains below the preset maximum allowable deformation threshold and no permanent deformation signal is fed back after depressurization, the controller outputs a "strength test passed" signal.

[0059] After the test, the controller first controls the cabin pressure relief valve to open at a preset rate (e.g., not exceeding 5 kPa / s) to slowly reduce the cabin pressure to atmospheric pressure, avoiding structural damage caused by rapid depressurization. Subsequently, the controller opens the pipeline pressure relief valve to release residual pressure in the test bench and hoses. Finally, the controller issues a prompt, allowing the removal of process actuator 11 and restoration of the aircraft to its original state.

[0060] Preferably, if the deformation is always below the maximum allowable deformation threshold and there is no permanent deformation after decompression, the controller outputs a strength test qualified signal; otherwise, it outputs an alarm signal.

[0061] Strictly ensure that the cockpit structure strength and rigidity meet the usage requirements to avoid hidden structural damage; the controller automatically outputs pass / alarm signals to improve test judgment efficiency and reduce safety risks.

[0062] In summary, this application has the following advantages:

[0063] Optimize the production process: The assembly process of the cockpit canopy pneumatic hydraulic system was successfully moved to the final assembly stage, completely avoiding the overlap of processes and repeated disassembly and assembly between the sub-assembly and final assembly stages.

[0064] Shortened production cycle: No longer constrained by the shortage of pneumatic and hydraulic system components, the airtightness and strength tests during the assembly stage can be carried out independently and in advance, significantly reducing the overall production cycle of the aircraft.

[0065] Ensuring test safety: Through a dedicated external test bench and automated hydraulic locking control, the cockpit canopy can be reliably locked even without installing the original system, completely eliminating the safety risk of "canopy jumping".

[0066] Cost savings: Reduces manpower waste and potential risk of parts damage caused by repeated disassembly and assembly.

[0067] The dedicated test bench and process method provided in this application can be widely applied to the assembly and repair of aircraft models with similar hydraulic canopy locking mechanisms. In particular, it is suitable for scenarios where the assembly of pneumatic and hydraulic systems needs to be moved back due to process arrangement or missing parts, and has significant effects on improving production efficiency and ensuring safety.

[0068] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A dedicated test bench for testing the airtightness and strength of an aircraft cockpit canopy, characterized in that, Includes an oil tank (2), a manual pump (4), a reversing valve (9), a process actuator (11), and a controller; The reversing valve (9) is a three-position four-way reversing valve. Two oil ports on one side of the reversing valve (9) are connected to the manual pump (4) and the oil tank (2), and two oil ports on the other side are connected to the inlet and outlet oil ports of the process actuator (11) through the hydraulic hose (10). The oil tank (2) is connected to the manual pump (4), and the manual pump (4) and the reversing valve (9) are equipped with sensors, which are electrically connected to the controller; A locking valve (5) is provided between the manual pump (4) and the reversing valve (9), and between the oil tank (2) and the reversing valve (9). The locking valve (5) is a two-position two-way solenoid valve, and the locking valve (5) is electrically connected to the controller. The reversing valve (9) has a positive position, a closed position and a reverse position. The controller drives the reversing valve (9) to move to the negative position and the positive position respectively, and controls the process actuator (11) to complete the retraction-extension cycle until the gas in the oil circuit is discharged. After the sensor detects that the hatch is closed, the controller controls the locking valve (5) to close, cutting off the oil circuit; The process actuator (11) is manufactured in a 1:1 ratio; After exhausting the air, install the process actuator (11) to the corresponding mounting point on the aircraft cockpit canopy.

2. The dedicated test bench for testing the airtightness and strength of an aircraft cockpit canopy as described in claim 1, characterized in that, A pressure gauge (8) is also provided between the manual pump (4) and the reversing valve (9). The pressure gauge (8) is connected between the shut-off valve (5) and the reversing valve (9) through a three-way connector (6) and a pressure gauge connector (7). The oil tank (2) is connected to an oil filter (1) at the bottom and a filter (3) is provided at the top.

3. The dedicated test bench for testing the airtightness and strength of an aircraft cockpit canopy as described in claim 1, characterized in that, The sensor is one or more of the following: proximity switch, limit sensor, bubble sensor, displacement sensor, pressure sensor, or strain gauge.

4. A process method for testing the airtightness and strength of an aircraft cockpit canopy, employing a dedicated test bench as described in any one of claims 1-3, characterized in that, Includes the following steps: The controller controls the piston rod of the process actuator (11) to extend continuously according to the preset step pressure value, pressurizes the aircraft cabin in sequence, and monitors the pressure drop rate in the cabin. If the pressure drop rate exceeds the threshold, an alarm is output. The controller raises the pressure to a preset value and maintains it for a preset duration, while monitoring the structural deformation of the aircraft cabin through sensors.

5. The process method for testing the airtightness and strength of the aircraft cockpit canopy as described in claim 4, characterized in that, The preset step pressure values ​​are 9.8 kPa, 19.6 kPa, 29.4 kPa, and 39.2 kPa, respectively. After each pressure level is reached, the pressure is stabilized for a preset time. The controller collects the pressure sensor signals in the cabin in real time and calculates the pressure drop rate per unit time.

6. The process method for testing the airtightness and strength of an aircraft cockpit canopy as described in claim 5, characterized in that, After completing all the step pressurization, the controller records the actual time it takes for the cabin pressure to drop from 39.2 kPa to 19.6 kPa. When the recorded actual time is greater than or equal to the preset qualified threshold, the airtightness test is deemed qualified.

7. The process method for testing the airtightness and strength of an aircraft cockpit canopy as described in claim 6, characterized in that, The controller raises the cabin pressure to 49 kPa and maintains it for 2 to 3 minutes, and collects deformation signals of the canopy and surrounding structures in real time through displacement sensors or strain gauges.

8. The process method for testing the airtightness and strength of an aircraft cockpit canopy as described in claim 7, characterized in that, If the deformation is consistently below the maximum allowable deformation threshold and there is no permanent deformation after decompression, the controller outputs a strength test pass signal; otherwise, it outputs an alarm signal.

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