Docking mechanism small cavity leakage rate test tool and test method

Abstract

The application provides a docking mechanism small cavity leak rate test tool and test method related to the field of leak rate test, which comprises an upper head assembly and a leak detection pipeline assembly, the leak detection pipeline assembly is connected to the upper head assembly, the upper head assembly is sealed and locked with a docking mechanism product to be tested to form a small cavity space, the leak detection pipeline assembly inflates the small cavity space of the docking mechanism product to be tested, and the internal pressure of the small cavity is tested in real time. Through the design of the upper head assembly, the setting of the pre-tightening force of the docking lock mold simulation part hook, the functional performance of the passive part of the docking mechanism is fully simulated, the cooperation of the active and passive parts of the docking mechanism during the small cavity leak rate test is avoided, the complexity of the test tool system is effectively simplified, the operation process is simplified, and the operation difficulty is reduced. Through the series connection of the gas pressure sensor in the leak detection pipeline, the product pipeline pressure is monitored in real time, the difficulty of the leak rate test is reduced in the mechanical and electrical combination mode, and the reliability of the leak rate test is ensured by the reverse installation of the stop valve to ensure the air tightness after being closed.

Description

Technical Field

[0001] This invention relates to the field of leak rate testing, and more specifically, to a leak rate testing fixture and method for a small cavity of a docking mechanism. Background Technology

[0002] The docking mechanism is a key technology for the rendezvous and docking mission of the second phase of the manned space program. It is an important execution mechanism for the rendezvous and docking of two spacecraft and an important product for subsequent manned space activities.

[0003] The docking mechanism primarily achieves capture, buffering, rigid connection, and sealing of the two spacecraft through the cooperation of the active and passive ends, ensuring the joint flight, docking, and separation of the spacecraft assembly in orbit. After the two spacecraft dock in orbit, the leakage rate test of the small cavity of the docking mechanism can serve as an important indicator for quickly determining whether the docking was successful. Simultaneously, because the two sealing rings on the docking surface will be compressed after the docking mechanism is sealed, the pressure between the two sealing rings will be lower than the pressure inside the docking mechanism channel, which may prevent the two spacecraft from separating normally. This is especially true during manned spaceflight, and abnormal separation during the return of the manned spacecraft poses a significant threat to the personal safety of the astronauts. Therefore, in abnormal situations, air is injected between the two sealing rings through the small cavity to ensure the normal separation of the two spacecraft.

[0004] Therefore, the leakage rate of the small cavity of the docking mechanism directly affects the stability and reliability of the two aircraft after docking. In order to verify the assembly quality of the docking mechanism and obtain the leakage rate of the small cavity of the product, it is necessary to design a test fixture and provide a corresponding test method. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the purpose of this invention is to provide a testing fixture and method for testing the leakage rate of small cavities in docking mechanisms.

[0006] According to the present invention, a small cavity leakage rate testing fixture for a docking mechanism includes an upper end cap assembly and a leak detection pipeline assembly. The leak detection pipeline assembly is connected to the upper end cap assembly. The upper end cap assembly and the docking mechanism product under test are sealed and locked to form a small cavity space. The leak detection pipeline assembly inflates the small cavity space of the docking mechanism product under test and tests the internal pressure of the small cavity in real time.

[0007] In some embodiments, the upper end cap assembly includes an upper end cap structure, a docking lock simulation component, a guide component, and a lifting lug. The docking lock simulation component is connected to the upper end cap structure, the guide component is provided on the docking surface of the upper end cap structure, and the lifting lug is provided on the top of the upper end cap structure.

[0008] In some embodiments, the upper end cap assembly is locked to the active docking lock on the product under test by a docking lock simulation component. The docking surface of the upper end cap structure is pressed together with two sealing rings on the docking surface of the product under test, forming a small cavity space between the two sealing rings.

[0009] In some embodiments, the guide is a guide pin or guide sleeve, which mates with the guide sleeve or guide pin at the end of the product under test.

[0010] In some embodiments, the docking lock simulation component includes a lock hook, a housing, a disc spring assembly, and a locking nut. The lock hook and the disc spring assembly are mounted on the housing via the locking nut. The upper end cap structure and the product under test are locked together by the lock hook, and the disc spring assembly provides preload.

[0011] In some embodiments, one end of the locking hook engages with the active docking locking hook on the product under test, while the other end is a screw-type structure, with the locking nut threaded into the locking hook screw.

[0012] In some embodiments, the leak detection pipeline assembly includes a connecting pipe, an adapter box, a shut-off valve, and a gas cylinder assembly. One end of the connecting pipe is connected to the inflation port of the small cavity space, and the other end of the connecting pipe is connected to the adapter box. The adapter box is connected to the shut-off valve through the pipe, and the shut-off valve is connected to the gas cylinder assembly through the pipe.

[0013] In some embodiments, a sensor is installed on the adapter box, the sensor is connected to a display, and the display shows the pressure in the connected piping system in real time.

[0014] This invention also provides a testing method for a tooling fixture for testing the leakage rate of a small cavity in a docking mechanism, the specific implementation steps of which are as follows:

[0015] Step S1: Clean the mating surface of the product under test and the two sealing rings on the mating surface. Lift the upper end assembly using the lifting lugs, clean the mating surface of the upper end assembly, and slowly place it on the mating surface of the product under test using the guide.

[0016] Step S2: The tested product actively engages with the lock and is powered on. By cooperating with the docking lock simulation component on the upper end cap assembly, the tested docking mechanism product is sealed and locked to the upper end cap assembly.

[0017] Step S3: Connect the leak detection pipeline assembly, reverse the shut-off valve on the air inlet pipe, and connect the gas cylinder assembly;

[0018] Step S4: Power on the display, inflate the small cavity to pressure P, stabilize the pressure for time t1, and record the pressure value p1; close the shut-off valve and disconnect the air inlet pipe; maintain the pressure for time t2, record the data every time interval Δt, and the last pressure value is p2;

[0019] Step S5: After the test is completed, open the shut-off valve, adjust the gas to atmospheric pressure, and close the shut-off valve; disconnect the hose connector at the inlet valve end, put it into an inverted measuring cup filled with water, and place the measuring cup in a bucket of water, open the shut-off valve, and after the pressure is balanced, read the volume V of the gas in the measuring cup.

[0020] Step S6: Turn off the pressure indicator, disconnect the power, remove the leak detection tubing assembly, and calculate the small cavity leak rate:

[0021] Q = (p1 - p2) * V / t2.

[0022] In some embodiments, in step S4, the stabilization time t1 ≥ 10 minutes, the holding time t2 ≥ 30 minutes, and the time Δt ≤ 2 minutes.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] (1) By designing the upper end cap assembly and setting the pre-tightening force of the locking hook of the docking lock simulation component, this invention fully simulates the functional performance of the passive component of the docking mechanism, avoids the coordination between the active and passive components of the docking mechanism during the small cavity leakage rate test, effectively simplifies the complexity of the test tooling system, simplifies the operation process, and reduces the difficulty of operation.

[0025] (2) This invention uses a gas pressure sensor connected in series in the leak detection pipeline to monitor the product pipeline pressure in real time. The electromechanical combination reduces the difficulty of leak rate testing. It also innovatively uses the reverse installation of the inlet shut-off valve to further ensure that the gas in the pipeline can only enter and not exit, ensuring airtightness after closing and ensuring the reliability of leak rate testing. Attached Figure Description

[0026] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0027] Figure 1 This is a schematic diagram of the principle of the small cavity leakage rate testing fixture of the docking mechanism of the present invention;

[0028] Figure 2 This is a front view of the head assembly of the small cavity leakage rate testing fixture of the docking mechanism of the present invention;

[0029] Figure 3 This is a top view of the head assembly of the small cavity leakage rate testing fixture of the docking mechanism of the present invention;

[0030] Figure 4 This is a schematic diagram of the docking lock simulation component of the small cavity leakage rate testing tooling of the docking mechanism of the present invention;

[0031] Figure 5 This is a schematic diagram of the leak detection pipeline assembly of the small cavity leak rate testing tooling for the docking mechanism of the present invention;

[0032] Figure 6 This is a schematic diagram of the small cavity space formed after the docking mechanism leak rate testing fixture of the present invention is connected and sealed with the docking mechanism product under test;

[0033] Marked in the image:

[0034] 10-Upper head assembly; 11-Upper head structural component; 12-Diamond lock simulation component; 13-Guide component; 14-Lifting lug; 121-Locking hook; 122-Housing; 123-Disc spring assembly; 124-Locking nut; 20-Leak detection pipeline assembly; 21-Connecting pipeline; 22-Adapter box; 23-Sensor; 24-Display; 25-Stop valve. Detailed Implementation

[0035] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0036] Example 1

[0037] According to the present invention, a small cavity leakage rate testing fixture for a docking mechanism is provided, such as... Figure 1 The device includes an upper end cap assembly 10 and a leak detection pipeline assembly 20. The leak detection pipeline assembly 20 is connected to the upper end cap assembly 10. The upper end cap assembly 10 and the tested docking mechanism product are sealed and locked to form a small cavity space. The leak detection pipeline assembly 20 inflates the small cavity space of the tested docking mechanism product and tests the internal pressure of the small cavity in real time.

[0038] like Figure 2 , Figure 3 As shown, the upper end cap assembly 10 consists of upper end cap structural components 11 and 12, circumferentially distributed docking lock simulation components 12, three circumferentially distributed guide components 13, and lifting lugs 14. The upper end cap assembly 10 simulates the passive component of the docking mechanism. It locks with the active docking lock on the tested product through the docking lock simulation components 12. The docking surface of the upper end cap structural component 11 is pressed against two sealing rings on the docking surface of the tested product, forming a small cavity space between the two sealing rings. Figure 6 As shown. The upper end cap structure 11 is a metal structural component designed according to the structural form of the product under test. Its mating surface is provided with mounting holes for a mating lock simulation component 12 and a guide component 13; its upper end face is provided with lifting points for installing lifting lugs 14, facilitating lifting and installation. The guide component 13 is a guide pin or guide sleeve, which cooperates with the guide sleeve or guide pin at the end of the product under test. Preferably, in this embodiment, the guide component 13 is a guide pin, used to cooperate with the guide sleeve at the end of the product under test, and installed on the upper end cap structure 11. Figure 4As shown, the docking lock simulation component 12 is installed on the upper end cap structure 11 by screws. It mainly consists of a locking hook 121, a housing 122, a disc spring assembly 123, and a locking nut 124. The locking hook 121 and the disc spring assembly 123 are installed on the housing 122 by the locking nut 124. The locking hook 121 is used to cooperate with the active docking lock hook on the product under test to lock the upper end cap assembly 10 and the product under test. The disc spring assembly 123 is used to provide preload force. In this embodiment, the preload force of the disc spring assembly is not less than 20KN to ensure the reliability and stability of the locking.

[0039] like Figure 5 As shown, the leak detection pipeline assembly 20 consists of a connecting pipe 21, an adapter box 22, a sensor 23, a shut-off valve 24, a display 25, and a gas cylinder assembly. It is used to inflate the small cavity of the tested docking mechanism product and to test the internal pressure of the small cavity in real time. One end of the connecting pipe 21 is sealed to the inflation port of the small cavity of the tested product via screws and a sealing ring, while the other end is connected to the adapter box 22. The adapter box 22 is connected to the shut-off valve 24 via a pipe, and the shut-off valve 24 is connected to the gas cylinder assembly via a pipe. The sensor 23 is installed in the adapter box 22 and is connected to the display 25, which displays the pressure in the connecting pipeline system in real time.

[0040] Example 2

[0041] This invention also provides a testing method for a tooling fixture for testing the leakage rate of a small cavity in a docking mechanism, the specific implementation steps of which are as follows:

[0042] Step S1: Clean the mating surface of the product under test and the two sealing rings on the mating surface. Lift the upper end cap assembly 10 using the lifting lug 14, clean the mating surface of the upper end cap assembly 10, and slowly place it on the mating surface of the product under test using the guide 13.

[0043] Step S2: The tested product actively connects to the lock and is powered on. By cooperating with the docking lock simulation part 12 on the upper end cap assembly 10, the tested docking mechanism product is sealed and locked to the upper end cap assembly 10.

[0044] Step S3: Connect the leak detection pipeline assembly 20, reverse the shut-off valve 25 on the air inlet pipe, and connect the gas cylinder assembly;

[0045] Step S4: Power on display 24, inflate the small cavity to pressure P, stabilize the pressure for time t1, and record the pressure value p1; close shut-off valve 25 and disconnect the air inlet pipe; maintain pressure for time t2, record data once every time interval Δt, and the last pressure value is p2;

[0046] Step S5: After the test is completed, open the shut-off valve 25, adjust the gas to atmospheric pressure, and close the shut-off valve 25; disconnect the hose connector at the inlet valve end, put it into an inverted measuring cup filled with water, and place the measuring cup in a bucket of water, open the shut-off valve 25, and after the pressure is balanced, read the volume V of the gas in the measuring cup.

[0047] Step S6: Turn off the pressure display, disconnect the power, remove the leak detection tubing assembly 20, and calculate the small cavity leak rate:

[0048] Q = (p1 - p2) * V / t2.

[0049] In some embodiments, in step S4, the stabilization time t1 ≥ 10 minutes, the holding time t2 ≥ 30 minutes, and the time Δt ≤ 2 minutes.

[0050] Example 3

[0051] This embodiment 3 is based on embodiment 2, and the specific steps are as follows:

[0052] Step S1: Clean the mating surface of the product under test and the two sealing rings on the mating surface to avoid foreign matter affecting the sealing of the assembly. Lift the upper end cap assembly 10 with the lifting lug 14, clean the mating surface of the upper end cap assembly, and slowly place it on the mating surface of the product under test using the guide pin 13.

[0053] Step S2: The tested product actively engages with the locking mechanism and is powered on. Through cooperation with the locking simulation component 12 on the upper end cap assembly, the tested docking mechanism is sealed and locked to the upper end cap assembly 10, forming a tight seal. Figure 5 The small cavity space shown;

[0054] Step S3: Connect the leak detection pipeline assembly 20, reverse the air inlet shut-off valve 24, and connect the nitrogen cylinder;

[0055] Step S4: Power on display 25, inflate the small cavity to 0.14MPa, stabilize the pressure for 10 minutes, and record the pressure value p1; close the air inlet valve and disconnect the air inlet pipe; maintain the pressure for 30 minutes (1800s), record the data every 1 minute, and the last pressure value is p2;

[0056] Step S5: After the test is completed, open the air inlet valve 24, adjust the gas pressure to 0.1MPa, and close the air inlet valve 24. Disconnect the hose connector at the end of the air inlet valve 24 and place it into an inverted measuring cup filled with water. Place the measuring cup in a bucket of water, open the valve, and after the pressure is balanced, read the volume V of the gas in the measuring cup.

[0057] Step S6: Turn off the pressure display 25, disconnect the power, disconnect the connecting pipe 21, and calculate the small cavity leakage rate:

[0058] Q = (p1-p2)*V / 1800.

[0059] This invention provides a fixture and method for testing the leakage rate of small cavities in docking mechanisms. The fixture has a simple structure and testing principle, avoiding the disassembly and assembly of pipelines during testing, simplifying the operation process and reducing operational difficulty. By connecting a gas pressure sensor in series in the leak detection pipeline, the product pipeline pressure is monitored in real time, reducing the difficulty of leak rate testing. Innovatively, by reversing the installation of the shut-off valve, it further ensures that gas can only enter and not exit the pipeline, guaranteeing the airtightness after closure and ensuring the reliability of the leak rate test. This invention solves the technical problem of leak rate testing in small cavities of docking mechanisms.

[0060] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0061] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A tooling for testing the leakage rate of a small cavity in a docking mechanism, characterized in that, It includes an upper end cap assembly (10) and a leak detection pipeline assembly (20). The leak detection pipeline assembly (20) is connected to the upper end cap assembly (10). The upper end cap assembly (10) is sealed and locked with the tested docking mechanism product to form a small cavity space. The leak detection pipeline assembly (20) inflates the small cavity space of the tested docking mechanism product and tests the internal pressure of the small cavity in real time. The upper end cap assembly (10) includes an upper end cap structure (11), a docking lock simulation component (12), a guide component (13), and a lifting lug (14). The docking lock simulation component (12) is connected to the upper end cap structure (11). The guide component (13) is provided on the docking surface of the upper end cap structure (11), and the lifting lug (14) is provided on the top of the upper end cap structure (11). The guide (13) adopts a guide pin or guide sleeve, and the guide (13) cooperates with the guide sleeve or guide pin at the end of the product being tested; The docking lock simulation component (12) includes a lock hook (121), a housing (122), a disc spring assembly (123), and a locking nut (124). The lock hook (121) and the disc spring assembly (123) are mounted on the housing (122) by the locking nut (124). The upper end cap structure (11) and the product under test are locked by the lock hook (121), and the disc spring assembly (123) provides preload.

2. The leak rate testing fixture for the small cavity of the docking mechanism according to claim 1, characterized in that, The upper end cap assembly (10) is locked with the active docking lock on the product under test through the docking lock simulation component (12). The docking surface of the upper end cap structure component (11) is pressed together with two sealing rings on the docking surface of the product under test, and a small cavity space is formed between the two sealing rings.

3. The tooling for testing the leakage rate of the small cavity of the docking mechanism according to claim 1, characterized in that, One end of the locking hook (121) engages with the active docking locking hook on the product being tested, and the other end is a screw-type structure. The locking nut (124) is threadedly engaged with the screw of the locking hook (121).

4. The tooling for testing the leakage rate of the small cavity of the docking mechanism according to claim 1, characterized in that, The leak detection pipeline assembly (20) includes a connecting pipeline (21), an adapter box (22), a shut-off valve (24), and a gas cylinder assembly. One end of the connecting pipeline (21) is connected to the inflation port of the small cavity space, and the other end of the connecting pipeline (21) is connected to the adapter box (22). The adapter box (22) is connected to the shut-off valve (24) through a pipeline, and the shut-off valve (24) is connected to the gas cylinder assembly through a pipeline.

5. The leak rate testing fixture for the small cavity of the docking mechanism according to claim 4, characterized in that, A sensor (23) is installed on the adapter box (22), and the sensor (23) is connected to a display (25). The display (25) displays the pressure in the connection pipeline (21) system in real time.

6. A testing method for the leakage rate testing fixture for the small cavity of the docking mechanism according to claim 5, characterized in that, The specific implementation steps are as follows: Step S1: Clean the mating surface of the product under test and the two sealing rings on the mating surface. Lift the upper end cap assembly (10) using the lifting lug (14), clean the mating surface of the upper end cap assembly (10), and slowly place it on the mating surface of the product under test using the guide (13). Step S2: The tested product actively connects to the lock and is powered on. By cooperating with the docking lock simulation part (12) on the upper end cap assembly (10), the tested docking mechanism product is sealed and locked to the upper end cap assembly (10). Step S3: Connect the leak detection pipeline assembly (20), reverse the shut-off valve (24) on the air inlet pipe, and connect it to the gas cylinder assembly; Step S4: Power on the display (25), inflate the small cavity space to pressure P, stabilize the pressure for time t1, and record the pressure value p1; close the shut-off valve (24) and disconnect the air inlet pipe; maintain the pressure for time t2, record the data once every time interval Δt, and the last pressure value is p2; Step S5: After the test is completed, open the shut-off valve (24) again, adjust the gas to atmospheric pressure, and close the shut-off valve (24); disconnect the hose connector at the inlet valve end, put it into an inverted measuring cup filled with water, and place the measuring cup in a bucket of water, open the shut-off valve (24), and after the pressure is balanced, read the volume V of the gas in the measuring cup. Step S6: Turn off the pressure display, disconnect the power, remove the leak detection tubing assembly (20), and calculate the small cavity leak rate: Q=(p1-p2)*V / t2.

7. The test method for the leakage rate test fixture of the docking mechanism small cavity according to claim 6, characterized in that, In step S4, the stabilization time t1 ≥ 10 minutes, the holding time t2 ≥ 30 minutes, and the time Δt ≤ 2 minutes.

Images