An auxiliary clamping device for high-model testing of liquid rocket engines

Abstract

The present invention relates to the field of space launch vehicle technology, and provides an auxiliary clamping device for high-model testing of liquid rocket engines, comprising: a clamping base, used to be connected to a bulkhead seat of a test vacuum chamber; a clamping mechanism, arranged on the clamping base; the clamping mechanism comprises a plurality of clamping members, and the plurality of clamping members are arranged at equal intervals along the circumferential direction of the clamping base; each clamping member comprises a fixed seat, a clamping cylinder and a top connection portion; the fixed seat is arranged on the clamping base, and the cylinder body of the clamping cylinder is connected to the fixed seat; the top connection portion is connected to the piston of the clamping cylinder. The auxiliary clamping device, under the premise that the top end of the engine is fixed, uses the auxiliary clamping device to perform auxiliary lateral limiting in the middle of the engine, thereby reducing lateral vibration and structural deformation caused by vibration, reducing the risk of collision between the nozzle and the diffuser, and improving the reliability and safety of the test.

Description

Technical Field

[0001] The invention relates to the technical field of space launch vehicles, and in particular to an auxiliary clamping device for high-model testing of liquid rocket engines. Background Art

[0002] Liquid rockets are the main carriers in the aerospace field, supporting important aerospace missions such as manned lunar landing and deep space exploration. Liquid carrier rockets generally adopt a combination of basic stage and upper stage. The upper stage engine can optimize engine performance by increasing the nozzle area ratio and improve the deep space capability of the upper stage rocket. Considering various factors such as structure, heat dissipation, performance, and weight reduction, the upper stage engine adopts a thin-walled rotating body structure with large axial and radial dimensions. In order to conduct deep space capability assessment, the upper stage engine needs to undergo high-mode testing, that is, engine testing in a closed vacuum environment. In the high-mode test of the engine, the top of the engine is fixed on the test foundation, and the tail nozzle extends into the diffuser of the ejection system. In order to improve the ejection capability of the test system, the gap between the tail outlet and the diffuser inlet is set very small. However, the engine test process is a physical and chemical process with high-density energy release, intense heat exchange, and complex operating conditions. It will produce large shocks and vibrations. The nozzle will produce large deformations and lateral swings under high temperature, high stress, and high vibration conditions, and there is a risk of collision between the tail outlet and the diffuser inlet. Summary of the invention

[0003] Therefore, the technical problem to be solved by the present invention is that the engine nozzle in the prior art produces large deformation and lateral swing under high temperature, high stress and high vibration conditions, and there is a risk of collision between the tail outlet and the diffuser inlet, thereby providing an auxiliary clamping device for high-model testing of liquid rocket engines.

[0004] In order to solve the above technical problems, the technical solution of the present invention is as follows:

[0005] The present invention provides an auxiliary clamping device for high-model testing of a liquid rocket engine, comprising: a clamping base, which is in an annular structure and is used to be connected to a bulkhead seat of a test vacuum chamber; a clamping mechanism, which is arranged on the clamping base; the clamping mechanism comprises a plurality of clamping members, and the plurality of clamping members are arranged at equal intervals along the circumferential direction of the clamping base; each of the clamping members comprises a fixed seat, a clamping cylinder and a top connection portion; the fixed seat is arranged on the clamping base, and the cylinder body of the clamping cylinder is connected to the fixed seat; the top connection portion is connected to the piston of the clamping cylinder, and when the engine needs to be clamped, the clamping cylinder drives the top connection portion through the piston toward the center of the clamping base to press against the connecting flange between the engine tail outlet and the nozzle.

[0006] Furthermore, the clamping mechanism also includes a pin seat, a first rotating shaft and a telescopic arm; the pin seat is connected to an end of the fixed seat away from the clamping base; the telescopic arm is rotatably arranged on the pin seat through the first rotating shaft; the clamping cylinder is arranged at an end of the telescopic arm away from the pin seat.

[0007] Furthermore, the clamping mechanism also includes a telescopic cylinder; the telescopic cylinder is arranged in the telescopic arm, and the cylinder body of the telescopic cylinder is connected to the upper section of the telescopic arm, and the piston of the telescopic cylinder is connected to the lower section of the telescopic arm.

[0008] Furthermore, the clamping mechanism also includes a rotating cylinder, a rack and a gear; the rotating cylinder is arranged on one side of the pin shaft seat, and the piston of the rotating cylinder is connected to the rack; the gear sleeve is arranged on the first rotating shaft, and the gear is meshed with the rack, and the rotating cylinder drives the first rotating shaft to rotate through the rack and the gear, and the first rotating shaft drives the telescopic arm to rotate synchronously.

[0009] Furthermore, the clamping mechanism also includes a latch cylinder and a latch; the latch cylinder is arranged on the side of the pin shaft seat opposite to the side where the rotating cylinder is located, and the latch is connected to the piston of the latch cylinder; the telescopic arm is provided with a clamping latch hole and a flipping latch hole; when the telescopic arm is rotated downward to the clamping position, the latch cylinder drives the latch to be inserted into the clamping latch hole to limit the telescopic arm in the clamping position; when the telescopic arm is rotated to the flipping position, the latch cylinder drives the latch to be inserted into the flipping latch hole to limit the telescopic arm in the flipping position.

[0010] Furthermore, the top connection portion is a top screw, which is threadedly connected to the piston of the clamping cylinder and is locked on the piston by a locking nut; when clamping is required, the top screw maintains contact with the connecting flange but does not apply a tightening force.

[0011] Furthermore, the auxiliary clamping device for the high-model test of the liquid rocket engine also includes a connecting plate, a second rotating shaft, a guide rod and a disc spring; the connecting plate is connected to the lower section of the telescopic arm by bolts; the cylinder body of the clamping cylinder is rotatably arranged on the connecting plate through the second rotating shaft; the cylinder body of the clamping cylinder is connected to the lower section of the telescopic arm through a guide rod, and the disc spring is sleeved on the guide rod, and the angle between the clamping cylinder and the lower section of the telescopic arm is adjusted by increasing or decreasing the preload of the disc spring.

[0012] Furthermore, the auxiliary clamping device for the high-model test of the liquid rocket engine also includes a stroke adjustment cylinder, which is threadedly connected to the end of the piston of the clamping cylinder away from the top screw and is locked by a set screw to adjust the stroke of the clamping cylinder.

[0013] Furthermore, the clamping cylinder is a gas cylinder, and the gas source used by the clamping cylinder is a nitrogen source.

[0014] Furthermore, during the startup or shutdown period of the engine, the top connection portion abuts against the connecting flange between the engine tail outlet and the nozzle.

[0015] The technical solution of the present invention has the following advantages:

[0016] The auxiliary clamping device for the high-model test of a liquid rocket engine provided by the present invention connects the clamping base with the bulkhead seat of the test vacuum chamber, and the clamping parts are arranged at equal intervals along the circumferential direction of the clamping base. When the engine needs to be clamped, the clamping cylinder drives the top connection part toward the center of the clamping base through the piston to press against the connecting flange between the engine tail outlet and the nozzle. With such an arrangement, under the premise that the top of the engine is fixed, the auxiliary clamping device is used to perform auxiliary lateral limiting in the middle of the engine, thereby reducing lateral vibration and structural deformation caused by vibration, reducing the risk of collision between the nozzle and the diffuser, and improving the reliability and safety of the test. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 It is a schematic diagram of the engine test state in the prior art;

[0019] Figure 2 It is a schematic diagram of the auxiliary clamping device for the high-model test of a liquid rocket engine in an embodiment of the present invention in a clamping state;

[0020] Figure 3 It is a schematic diagram of the enlarged local structure of the auxiliary clamping device for the high-model test of a liquid rocket engine in an embodiment of the present invention when it is in a clamping state;

[0021] Figure 4 It is a schematic diagram of the auxiliary clamping device for the high-model test of a liquid rocket engine in an embodiment of the present invention in a flipped-up state;

[0022] Figure 5A schematic diagram of a perspective of a pin shaft seat in an auxiliary clamping device for a high-model test of a liquid rocket engine in an embodiment of the present invention;

[0023] Figure 6 It is a schematic diagram of another viewing angle of the pin shaft seat in the auxiliary clamping device for the high-model test of the liquid rocket engine in the embodiment of the present invention;

[0024] Figure 7 It is a schematic diagram of a telescopic arm in an auxiliary clamping device for a high-model test of a liquid rocket engine in an embodiment of the present invention;

[0025] Figure 8 It is a schematic diagram of the telescopic cylinder in the auxiliary clamping device for the high-model test of the liquid rocket engine in the embodiment of the present invention;

[0026] Fig. 9 It is a schematic diagram of the clamping cylinder in the auxiliary clamping device for the high-model test of the liquid rocket engine in an embodiment of the present invention.

[0027] Description of reference numerals:

[0028] 1. Vacuum chamber; 2. Thrust frame; 3. Engine; 4. Nozzle; 5. Connecting flange; 6. Clamping base; 7. Clamping member; 8. Support leg; 9. Clamping cylinder; 10. Top connection part; 11. Fixed seat; 12. Pin seat; 13. Rotating cylinder; 14. First rotating shaft; 15. Telescopic arm; 16. Latch cylinder; 17. Turn up latch hole; 18. Clamping latch hole; 19. Upper section; 20. Lower section; 21. Telescopic cylinder; 22. Second rotating shaft; 23. Top screw; 24. Locking nut; 25. Guide rod; 26. Stroke adjustment cylinder; 27. Connecting plate. DETAILED DESCRIPTION

[0029] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0031] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0032] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0033] like Figure 1 As shown, it should be noted that the vacuum chamber 1 provides a vacuum environment for the high-mode test, and the auxiliary clamping device is an auxiliary support for limiting the vibration of the engine 3 during the on-off period. During the test, the engine is placed in the vacuum chamber 1, the top of the engine 3 is connected to the thrust frame 2, and the tail of the engine 3 is connected to the nozzle 4.

[0034] Figure 2 , Figure 3 as well as Figure 4 As shown, this embodiment provides an auxiliary clamping device for high-model testing of liquid rocket engines, including: a clamping base 6, which is annular in structure and is used to be connected to the bulkhead seat of the test vacuum chamber 1; a clamping mechanism, which is arranged on the clamping base 6; the clamping mechanism includes a plurality of clamping members 7, and the plurality of clamping members 7 are arranged at equal intervals along the circumferential direction of the clamping base 6; each of the clamping members 7 includes a fixed seat 11, a clamping cylinder 9 and a top connection portion 10; the fixed seat 11 is arranged on the clamping base 6, and the cylinder body of the clamping cylinder 9 is connected to the fixed seat 11; the top connection portion 10 is connected to the piston of the clamping cylinder 9, and when the engine 3 needs to be clamped, the clamping cylinder 9 drives the top connection portion 10 toward the center of the clamping base 6 through the piston to press against the connecting flange 5 between the tail outlet of the engine 3 and the nozzle 4. For example, the clamping base 6 can be fixed on the bulkhead seat of the vacuum chamber 1 by four legs 8, and three clamping members 7 can be arranged on the annular clamping base 6 at intervals of 120°. The engine 3 is divided into an engine 3 section and a nozzle 4 section, and the two are connected together by a connecting flange 5. The auxiliary clamping device is supported on the edge of the connecting flange 5 by the top connection portion 10 of the clamping member 7. Auxiliary limiting support is performed at the middle height position of the engine 3 to reduce the lateral swing and deformation of the nozzle 4. Moreover, before the engine 3 is ignited, in order to occupy the arrow-ground docking operation space, the auxiliary clamping device can be flipped and retracted.

[0035] The auxiliary clamping device for the high-model test of the liquid rocket engine provided in this embodiment connects the clamping base 6 with the bulkhead seat of the test vacuum chamber 1, and the clamping parts 7 are arranged at equal intervals along the circumferential direction of the clamping base 6. When the engine 3 needs to be clamped, the clamping cylinder 9 drives the top connection part 10 toward the center of the clamping base 6 through the piston to press against the connecting flange 5 between the tail outlet of the engine 3 and the nozzle 4. With such a configuration, under the premise that the top of the engine 3 is fixed, the auxiliary clamping device is used to perform auxiliary lateral limiting in the middle of the engine 3, thereby reducing lateral vibration and structural deformation caused by vibration, reducing the risk of collision between the nozzle and the diffuser, and improving the reliability and safety of the test.

[0036] Among them, the clamping mechanism can complete the flipping, extending and clamping actions, and is mainly composed of cylinders corresponding to the three actions.

[0037] Specifically, if Figure 5 As shown, the clamping mechanism further includes a pin seat 12, a first rotating shaft 14 and a telescopic arm 15; the pin seat 12 is connected to the end of the fixed seat 11 away from the clamping base 6; the telescopic arm 15 is rotatably arranged on the pin seat 12 through the first rotating shaft 14; the clamping cylinder 9 is arranged at the end of the telescopic arm 15 away from the pin seat 12. The clamping mechanism further includes a rotating cylinder 13, a rack and a gear; the rotating cylinder 13 is arranged on one side of the pin seat 12, and the piston of the rotating cylinder 13 is connected to the rack; the gear is sleeved on the first rotating shaft 14, and the gear is meshed with the rack, the rotating cylinder 13 drives the first rotating shaft 14 to rotate through the rack and the gear, and the first rotating shaft 14 drives the telescopic arm 15 to rotate synchronously.

[0038] For example, the fixing seat 11 is located at the top, and the bottom can be connected to the pin seat 12 through a square flange and bolts. The first rotating shaft 14 can be rotatably installed in the rotating shaft hole of the pin seat 12. The rotating cylinder 13 can be installed on the left side of the pin seat 12, connected to the first rotating shaft 14 through the built-in rack and gear, and the rotation direction freedom is limited by a key. The telescopic arm 15 and the first rotating shaft 14 can be connected by an interference fit. When in use, the piston of the rotating cylinder 13 drives the rack to move linearly under the pressure of the medium, and the linear motion of the piston is converted into the rotation of the telescopic arm 15 through the rack and gear, so that the telescopic arm 15 can be turned up or down.

[0039] like Figure 6 , Figure 7As shown, the clamping mechanism further includes a latch cylinder 16 and a latch pin; the latch cylinder 16 is arranged on the side opposite to the side where the rotating cylinder 13 is located on the pin shaft seat 12, and the latch pin is connected to the piston of the latch cylinder 16; the telescopic arm 15 is provided with a clamping latch pin hole 18 and a flip-up latch pin hole 17; when the telescopic arm 15 rotates downward to the clamping position, the latch cylinder 16 drives the latch pin to be inserted into the clamping latch pin hole 18 to limit the telescopic arm 15 in the clamping position; when the telescopic arm 15 rotates to the flip-up position, the latch cylinder 16 drives the latch pin to be inserted into the flip-up latch pin hole 17 to limit the telescopic arm 15 in the flip-up position. For example, the latch cylinder 16 can be installed on the right side of the pin shaft seat 12, and the built-in piston is directly connected to the latch pin. The piston drives the latch pin to be inserted or pulled out under the pressure of the medium. For example, the latch can be a square head pin or other special-shaped pin, so that the telescopic arm 15 can be prevented from rotating after the latch is inserted. Two limit positions can be set on the rack in the rotating cylinder 13, which correspond to the positions of the flip-up latch hole 17 and the clamping latch hole 18 respectively. When the telescopic arm 15 rotates to the corresponding position, the latch is inserted to perform mechanical limit at the corresponding position.

[0040] like Figure 7 , Figure 8 As shown, the clamping mechanism further includes a telescopic cylinder 21; the telescopic cylinder 21 is disposed in the telescopic arm 15, and the cylinder body of the telescopic cylinder 21 is connected to the upper section 19 of the telescopic arm 15, and the piston of the telescopic cylinder 21 is connected to the lower section 20 of the telescopic arm 15. For example, the telescopic cylinder 21 is built into the telescopic arm 15, the upper end of the telescopic cylinder 21 can be fixed at a position close to the upper end of the upper section 19 of the telescopic arm 15, and the piston of the telescopic cylinder 21 is connected to the lower section 20 of the telescopic arm 15. When in use, the piston of the telescopic cylinder 21 extends or retracts the lower section 20 of the telescopic arm 15 under the push of the medium pressure.

[0041] like Fig. 9As shown, the auxiliary clamping device for the high-model test of the liquid rocket engine also includes a connecting plate 27, a second rotating shaft, a guide rod 25 and a disc spring; the connecting plate 27 is connected to the lower section 20 of the telescopic arm 15 by bolts; the cylinder body of the clamping cylinder 9 is rotatably arranged on the connecting plate 27 through the second rotating shaft; the cylinder body of the clamping cylinder 9 is connected to the lower section 20 of the telescopic arm 15 through the guide rod 25, and the disc spring is sleeved on the guide rod 25, and the angle between the clamping cylinder 9 and the lower section 20 of the telescopic arm 15 is adjusted by increasing or decreasing the preload of the disc spring. Wherein, the top connection part 10 is a top screw 23, the top screw 23 is threadedly connected to the piston of the clamping cylinder 9, and the top screw 23 is locked on the piston by a locking nut 24; when clamping is required, the top screw 23 keeps in contact with the connecting flange 5 between the tail outlet of the engine 3 and the nozzle 4 but does not apply a top force, that is, keeps a state of just contact. Among them, the auxiliary clamping device for the high-model test of the liquid rocket engine also includes a stroke adjustment cylinder 26, which is threadedly connected to the end of the piston of the clamping cylinder 9 away from the top screw 23 and is locked by a set screw to adjust the stroke of the clamping cylinder 9.

[0042] For example, two parallel spaced connection plates 27 can be installed on the lower section 20 of the telescopic arm 15 by bolts, the cylinder body of the clamping cylinder 9 is rotatably installed between the two connection plates by the second rotating shaft 22, and a guide rod 25 and a disc spring are arranged between the connection plate and the cylinder body of the clamping cylinder 9. For example, guide rods 25 can be arranged on both sides of the telescopic arm 15, and the preload of the disc spring can be reduced or increased by loosening or tightening the guide rod 25, and the pitch angle adjustment of the clamping cylinder 9 can be achieved by cooperating with the second rotating shaft 22. There are many arrow-shaped connection ports near the connecting flange 5 of the engine 3, and when the connection port and the clamping position interfere, they can be adjusted according to actual needs. The front end of the piston of the clamping cylinder 9 is threadedly connected to the top screw 23 and is equipped with a locking nut 24. The rear end of the piston is threadedly connected to the stroke adjustment cylinder 26 and locked by a set screw. When in use, the stroke of the clamping cylinder 9 can be adjusted by screwing the stroke adjustment cylinder 26. Specifically, when the piston extends out of the cylinder body of the clamping cylinder, the stroke adjustment cylinder will be against the cylinder body of the clamping cylinder due to the presence of the stroke adjustment cylinder at its tail end. At this time, the piston reaches the maximum stroke and cannot be extended further. If it is necessary to increase the stroke of the piston, the stroke adjustment cylinder can be loosened to increase the distance between it and the cylinder body of the clamping cylinder. Similarly, if it is necessary to reduce the stroke of the piston, the stroke adjustment cylinder can be tightened to reduce the distance between it and the cylinder body of the clamping cylinder. With this arrangement, the piston stroke and the top screw position of the clamping cylinder are both adjustable. The stroke is set as required during debugging, and the position of the stroke adjustment cylinder is locked with a set screw. When adjusting the piston stroke, leave a distance for the top screw adjustment, and then manually adjust the top screw position to achieve a state where the top screw contacts the connecting flange but does not apply a pre-tightening force, and lock the top screw position with a locking nut. When clamping is required, only the clamping cylinder needs to be switched on and off to achieve a state where the top screw just contacts the flange.

[0043] The clamping cylinder 9 is a gas cylinder, and the gas source used by the clamping cylinder 9 is a nitrogen source.

[0044] In the startup or shutdown period of the engine 3 , the top connection portion 10 abuts against the connection flange 5 between the tail outlet of the engine 3 and the nozzle 4 .

[0045] Among them, the clamping cylinder 9, the rotating cylinder 13, the telescopic cylinder 21 and the latch cylinder 16 can all be gas cylinders, and the gas source is nitrogen.

[0046] The clamping force of each clamping cylinder 9 can be selected according to 30000N.

[0047] When selecting the gas source, the compressed gas is required to have a stable pressure and sufficient flow rate, and the gas supply flow rate of the gas source should not be less than 6m 3 / h; the pressure value does not exceed 18Mpa; and a filter is provided on the pipeline for conveying the medium, which is installed at the inlet end of the pressure reducing valve to eliminate impurities in the medium to protect the normal use of the valve and equipment. For example, a filter with a screen accuracy of 10um, a diameter of DN15, and a maximum pressure resistance of 35MPa can be selected. A pressure reducing valve can be used as a pressure regulating device to reduce the pressure from the main gas source to meet the needs of each actuator and keep the pressure stable. A double pressure reducing valve circuit is used in the gas circuit. The main gas source first enters the first pressure reducing valve and then outputs to the gas storage bottle. The gas storage bottle is connected to the pressure reducing valve to output the working pressure again, which can ensure the stability of the pressure and eliminate fluctuations. A high-pressure seamless bottle pressure vessel can be used to store high-pressure gas, which plays the role of energy storage, pressure stabilization, and loss compensation in the system. A safety valve can be used as a safety protection valve. Its opening and closing parts are in a normally closed state under the action of external force. When the gas pressure in the pipeline increases and exceeds the specified value, it automatically opens to prevent the medium pressure in the pipeline or equipment from exceeding the specified value by discharging the medium outside the system. Solenoid valves can be used in the gas system to realize the opening and closing of the liquid circuit or the change of the direction of the liquid flow. In order to meet the safety requirements of the on-site environment, solenoid valves with a maximum pressure resistance of 15MPa and a working voltage of DC24V can be selected. When in use, the working pressure of the system gas source can be 18MPa. The gas source enters the pressure reducing device after purification by the filter to adjust the pressure of the control gas pressure system. The pressure reducing device is mainly composed of the first pressure reducer, the first pressure gauge, the one-way valve, the gas collecting bottle, the second pressure reducer, and the second pressure gauge. The gas storage bottle plays the role of energy storage, pressure stabilization, and loss compensation in the system. A safety valve is configured in the pressure reducing device to automatically exhaust the gas in case of overpressure. The setting value of the first pressure reducer is 8±0.1MPa, and the setting value of the second pressure reducer is 6±0.1MPa. After the gas source passes through the pressure reducing device to the set pressure, it is distributed to the branch control solenoid valve to realize the action of each cylinder. Each branch is equipped with a speed regulating valve, which can adjust the cylinder speed to ensure the consistency of the action of the three clamping arms.

[0048] Among them, the three clamping cylinders 9 can be uniformly controlled, and the pipelines adopt the same diameter and length to ensure the maximum synchronous response. The friction coefficient of each cylinder is the same to ensure the same output force under the same air pressure. Under the condition of stable air source, the clamping time of the three clamping cylinders 9 is less than 3 seconds, and the clamping and releasing time is less than 3 seconds. Other actions such as telescopic arm 15 extension, flipping, latching, plugging and unplugging have a beat of about 60 seconds.

[0049] A pressure sensor may be provided in the air circuit of the clamping cylinder 9 for pressure monitoring so as to monitor and convert the output clamping force in real time.

[0050] Among them, the control system is set as two unrelated safety control units, manual and automatic. Even if one fails, the other can independently complete the safety control task, thereby achieving safety control. When switching the manual control system, the automatic control system fails, and each step of the auxiliary clamping device can be performed with human intervention. The automatic control system sets the execution condition detection, judgment and control through the switch quantity. The specific method is: by connecting the switch quantity output signal to the PLC switch quantity input signal, the program outputs the switch quantity and performs the output performance test; by connecting the switch quantity input signal to the PLC switch quantity input signal, the program controls the switch quantity output, detects the input signal, and performs the input performance test; the feedback signal is connected to the PLC switch quantity input signal, and the PLC switch quantity output signal outputs the corresponding indicator light according to the input signal. All process quantities are collected through the bus, and the test results of each parameter are displayed on the operation panel.

[0051] Among them, the control mode is divided into local control, near control and remote control. Local control is to manually control the start / stop operation of the equipment through the switch or button on the control box panel, which is mainly used in the process of equipment debugging and maintenance. Near control is to communicate with the standby equipment through a wireless remote control to realize the switch state control of the equipment. Generally, after the engine 3 completes the arrow-ground docking, the personnel stand on the operating platform in the vacuum chamber 1 and observe and act before the engine 3 is ignited. Remote control is to realize remote control through signals and the measurement and control command hall. Generally, it is used in the two actions of clamping release and re-clamping automatically controlled by the engine 3 ignition program during the ignition process of the engine 3. For the convenience of use, the local control and remote control are both set with one-button automatic actions of flipping down and flipping up: the automatic flipping down action program automatically executes the clamping release, arm retraction, arm unlocking, arm flipping down, arm locking and arm extension. The automatic flipping up action program automatically executes the clamping release, arm retraction, arm unlocking, arm flipping up and arm locking.

[0052] In summary, the auxiliary clamping device for the high-model test of the liquid rocket engine in this application can assist in clamping, reduce the risk of collision, and improve the safety of the test. In the high-model test, the top frame of the engine 3 is fixed on the dynamic frame of the thrust measurement system, and the waist nozzle 4 and the engine 3 connection flange 5 are connected by a clamp 7 for auxiliary limiting, which can effectively suppress vibration and deformation, thereby reducing the risk of collision between the nozzle 4 outlet and the diffuser, and ensuring the safety of the test. Nitrogen is used as the medium source, which is safer than hydraulic, electrical and other medium sources, further ensuring the safety of the test.

[0053] The auxiliary clamping device for the high-model test of the liquid rocket engine in the present application adopts a combination of flipping, telescoping and clamping multiple cylinders, and can realize structural deformation through automated pneumatic technology, and can quickly and conveniently change from a clamping state to a retracted state. After retracting, the structure is located in the frame section, ensuring that the most concentrated section of the arrow-ground interface (from the frame to the nozzle 4 docking flange) is open and unobstructed, and does not affect personnel operation.

[0054] In the auxiliary clamping device for high-model testing of liquid rocket engines in the present application, the clamping cylinder 9 is fixed by a guide rod 25 with a butterfly spring and a second rotating shaft 22. The pitch angle of the clamping cylinder 9 can be finely adjusted by adjusting the tightness of the upper and lower butterfly springs to meet the structural deviations of the connecting flange 5 of the engine 3 to be tested of different models.

[0055] The auxiliary clamping device for the high-model test of the liquid rocket engine in the present application is designed to better control the contact state between the top screw 23 and the flange to achieve "just right contact". During the initial debugging, the top screw 23 is manually adjusted to achieve "just right contact" and locked with a locking nut 24.

[0056] The auxiliary clamping device for the high-model test of the liquid rocket engine in the present application has an adjustable clamping force of the clamping cylinder 9: a large clamping force can be achieved by using a cylinder as an actuator and a high-pressure pneumatic system as a power source. By adjusting the outlet pressure of the pressure reducer, the clamping force can be steplessly adjusted between 0 and the maximum clamping force. The clamping force can be accurately adjusted according to actual needs, and can better adapt to the structural needs of different engines 3.

[0057] The auxiliary clamping device for the high-model test of the liquid rocket engine in the present application has a flexible and convenient control mode: based on PLC automatic control technology, it adopts a far-near dual control mode, and sets interlocking and authority exchange under the two control modes, realizing operations with different needs at the front and rear ends of the test station, and meeting the various control modes of manual control by personnel at the front end of the vacuum chamber 1 before ignition and handing over the ignition program control to the command hall after ignition. The control mode is flexible and convenient, the control interface is clear, and it is in good compliance with the test process requirements.

[0058] The auxiliary clamping device for high-model test of liquid rocket engine in this application has an intrinsically safe program design: the system uses PLC as the data processing and control core and sensors as monitoring elements, monitors all action signals and integrates them into PLC for conditional execution detection to determine whether the conditions for executing the action are met. If the conditions for the action are not met, corresponding signal feedback is given until the conditions are met before the action is executed, thus realizing action chain protection. For example, when the arm is flipped down, it will detect the closing of the clamping cylinder 9 release switch, the full retraction switch of the telescopic cylinder 21, and the pin release switch of the latch cylinder 16 before the action is executed, thus avoiding human error and realizing intrinsically safe procedural operation of associated actions, making the system safer during operation.

[0059] The auxiliary clamping device of the high-mode test of the liquid rocket engine in this application does not affect the normal test of the engine 3: the auxiliary clamping is the damping of the thrust measurement of the engine 3, which will affect the accuracy of the thrust measurement. According to the working characteristics of the engine 3 test, the auxiliary clamping device is enabled only in the startup and shutdown stages with large vibrations, and the auxiliary clamping device is cancelled in the steady-state stage with small vibrations. The auxiliary clamping clamps before the engine 3 is started, and changes from near control to remote control, and the clamping is cancelled 10 seconds after the engine 3 is started. It clamps again 10 seconds before the engine 3 is shut down, and the remote control is changed to near control after shutdown, and the clamping is subsequently cancelled. After the engine 3 is working, the activation and cancellation of the clamping device are uniformly controlled by the engine 3 test program, which solves the coordination problem between the clamping device and the engine 3 working program, and achieves the purpose of not affecting the normal test of the engine 3 and not affecting the thrust measurement through the timing misalignment.

[0060] The auxiliary clamping device for the high-model test of the liquid rocket engine in this application has a fast and adjustable response and a stable system: the auxiliary clamping device adopts a high-pressure gas source, a large-caliber gas supply network and a two-stage pressure reducer to form a high-pressure and large-flow gas supply system to ensure that the front-end execution cylinder action responds quickly. Flow regulating valves are set on the main and branch gas supply lines. The cylinder speed can be adjusted by adjusting the flow to ensure that the action response is completed within the required time. The two action responses of canceling 10s after starting and clamping again 10s before shutting down do not exceed 1s, and the time difference of the three clamping arms is within 10ms. A high-pressure and large-capacity buffer gas cylinder is added in the middle of the two-stage pressure reducing valve. When the pressure deviation occurs in the first pressure reducing valve, it is adjusted by the gas storage cylinder and a stable pressure is output through the second pressure reducing valve, which solves the problem of pressure fluctuation in the high-pressure gas supply system. A safety valve is set in the middle of the two-stage pressure reducing valve. When the system exceeds the opening pressure of the safety valve, it is deflated, so that the system is safer.

[0061] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. An auxiliary clamping device for high-model testing of liquid rocket engines, characterized in that: include: The clamping base (6) is an annular structure and is used to be connected to the bulkhead seat of the test vacuum chamber (1); A clamping mechanism is arranged on the clamping base (6); the clamping mechanism comprises a plurality of clamping members (7), the plurality of clamping members (7) being arranged at equal intervals along the circumferential direction of the clamping base (6); each of the clamping members (7) comprises a fixing seat (11), a clamping cylinder (9) and a top connection portion (10); the fixing seat (11) is arranged on the clamping base (6), the cylinder body of the clamping cylinder (9) is connected to the fixing seat (11); the top connection portion (10) is connected to the piston of the clamping cylinder (9), and when the engine (3) needs to be clamped, the clamping cylinder (9) drives the top connection portion (10) through the piston toward the center of the clamping base (6) to press against the connecting flange (5) between the tail outlet of the engine (3) and the nozzle (4); The vacuum chamber (1) provides a vacuum environment for the high-mode test, and the auxiliary clamping device is an auxiliary support for limiting the vibration of the engine (3) during the on-off period. During the test, the engine (3) is placed in the vacuum chamber (1), the top of the engine (3) is connected to the thrust frame (2), and the tail of the engine (3) is connected to the nozzle (4).

2. The auxiliary clamping device for high-model testing of liquid rocket engines according to claim 1, characterized in that: The clamping mechanism further comprises a pin shaft seat (12), a first rotating shaft (14) and a telescopic arm (15); The pin seat (12) is connected to an end of the fixing seat (11) away from the clamping base (6); The telescopic arm (15) is rotatably arranged on the pin seat (12) via the first rotating shaft (14); The clamping cylinder (9) is arranged at an end of the telescopic arm (15) away from the pin seat (12).

3. The auxiliary clamping device for high-model testing of liquid rocket engines according to claim 2, characterized in that: The clamping mechanism also includes a telescopic cylinder (21); The telescopic cylinder (21) is arranged in the telescopic arm (15), and the cylinder body of the telescopic cylinder (21) is connected to the upper section (19) of the telescopic arm (15), and the piston of the telescopic cylinder (21) is connected to the lower section (20) of the telescopic arm (15).

4. The auxiliary clamping device for high-model testing of liquid rocket engines according to claim 2, characterized in that: The clamping mechanism also includes a rotating cylinder (13), a rack and a gear; The rotating cylinder (13) is arranged on one side of the pin shaft seat (12), and the piston of the rotating cylinder (13) is connected to the rack; The gear is sleeved on the first rotating shaft (14), and the gear is meshed with the rack. The rotating cylinder (13) drives the first rotating shaft (14) to rotate via the rack and the gear, and the first rotating shaft (14) drives the telescopic arm (15) to rotate synchronously.

5. The auxiliary clamping device for high-model testing of liquid rocket engines according to claim 4, characterized in that: The clamping mechanism also includes a latch cylinder (16) and a latch; The latch cylinder (16) is arranged on a side surface of the pin shaft seat (12) opposite to the side surface where the rotating cylinder (13) is located, and the latch pin is connected to a piston of the latch cylinder (16); The telescopic arm (15) is provided with a clamping latch hole (18) and a flipping latch hole (17); When the telescopic arm (15) rotates downward to a clamping position, the latch cylinder (16) drives the latch to be inserted into the clamping latch hole (18) to restrict the telescopic arm (15) to the clamping position; when the telescopic arm (15) rotates to a flipping position, the latch cylinder (16) drives the latch to be inserted into the flipping latch hole (17) to restrict the telescopic arm (15) to the flipping position.

6. The auxiliary clamping device for high-model testing of liquid rocket engines according to claim 2, characterized in that: The top connection portion (10) is a top screw (23), the top screw (23) is threadedly connected to the piston of the clamping cylinder (9), and the top screw (23) is locked on the piston via a locking nut (24); When clamping is required, the top screw (23) maintains contact with the connecting flange (5) but does not apply a tightening force.

7. The auxiliary clamping device for high-model testing of liquid rocket engines according to claim 6, characterized in that: It also includes a connecting plate (27), a second rotating shaft, a guide rod (25), and a disc spring; The connecting plate (27) is connected to the lower section (20) of the telescopic arm (15) via bolts; The cylinder body of the clamping cylinder (9) is rotatably arranged on the connecting plate via the second rotating shaft; The cylinder body of the clamping cylinder (9) is connected to the lower section (20) of the telescopic arm (15) via a guide rod (25), and the disc spring is sleeved on the guide rod (25). The angle between the clamping cylinder (9) and the lower section (20) of the telescopic arm (15) is adjusted by increasing or decreasing the preload of the disc spring.

8. The auxiliary clamping device for high-model testing of liquid rocket engines according to claim 6, characterized in that: It also includes a stroke adjustment cylinder (26), which is threadedly connected to one end of the piston of the clamping cylinder (9) away from the top screw (23) and is locked by a set screw to adjust the stroke of the clamping cylinder (9).

9. The auxiliary clamping device for high-model testing of liquid rocket engines according to claim 1, characterized in that: The clamping cylinder (9) is an air cylinder, and the air source used by the clamping cylinder (9) is a nitrogen source.

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