Servo driving scheme for gas vane thrust vectoring device of plug nozzle engine

Abstract

The invention relates to a gas vane thrust vectoring device servo driving scheme of a plug nozzle engine, which is specifically divided into a gas vane, a fixing device of the gas vane and an integrated electro-hydraulic servo control system, so that the gas vane is fixed on the surface of a plug cone, and the gas vane can be controlled to act at a specified angle according to requirements. In order to enable the gas vanes to generate large axial force and to have small axial loss at the same time, the gas vanes are evenly arranged at the 50% length position of the plug cone in the circumferential direction. In order to solve the problems of feasibility and reliability of axial fastening of the gas rudder shaft on the curved surface of the plug cone, a split type design and dual-bearing fastening are used. In order to guarantee the transmission rotation stability and accuracy of the gas vane, a servo motor is used for driving a hydraulic cylinder, and a double-rocker mechanism is formed to achieve driving. In order to ensure the flexibility and reliability of the thrust vector of the engine, a unit integrated electro-hydraulic servo system is adopted, so that each gas vane can independently realize vector control. The invention has the advantages of high structural reliability, high control accuracy and high vector maneuverability.

Description

Technical Field

[0001] The present invention is a servo drive scheme for a gas rudder thrust vector device of a plug-type nozzle engine, specifically, a scheme for using an integrated electro-hydraulic servo system and a planar double rocker mechanism to control the gas rudder arranged on the plug cone surface to perform reciprocating rotational motion, and is applied to the field of thrust vector control of plug-type nozzle engines. Background Art

[0002] The plug nozzle is a nozzle with height compensation characteristics. It can be used as a power system for single-stage or two-stage reusable space launch vehicles, hypersonic vehicles, and small solid rocket engines, and has broad application prospects. As a mechanical thrust vector control solution, the gas rudder has the advantages of fast response, high reliability, and simple structure. It is often used for thrust vector control at the outlet of the bell-shaped nozzle. Introducing the gas rudder technology into the plug nozzle poses new challenges to the installation and control of the gas rudder.

[0003] For bell-shaped nozzles, the gas rudder is fixed at the nozzle outlet in the form of an ear piece, and the servo control mechanism for manipulating the gas rudder is arranged inside the ear piece, wherein the ear piece is a planar structure, which is convenient for fixing the gas rudder and arranging the servo control mechanism. However, for plug-type nozzles, the surface of the plug cone is a curved structure, and how to fix the gas rudder and arrange the gas rudder control mechanism is a major problem. In order to solve the actuation control problem of the gas rudder, Chinese patents with publication number CN201710138606.5 disclose a linkage mechanism between an aircraft gas rudder and an air rudder, and Chinese patents with publication number CN202210405907.0 disclose a ball screw type gas rudder servo mechanism. Both patents use a motor-driven ball screw in conjunction with a connecting rod mechanism to servo-control the gas rudder. This control scheme is simple to control and can independently control the rotation of each rudder, but the scheme with the motor as the power source will double the volume and weight of the entire servo system when the required actuation power is large.

[0004] Based on the above problems, the present invention designs a servo drive scheme for a gas rudder thrust vector control device of a plug nozzle engine, in which the gas rudder is fastened to the surface of the plug cone by a fixing device, and the servo control system is arranged inside the plug cone, so as to rationally utilize the surface and internal space of the plug cone; an integrated electro-hydraulic servo system and a planar double rocker mechanism are used to control the deflection of the gas rudder, and each rudder blade rotates independently, so that more thrust vector combinations can be realized. The application of the electro-hydraulic servo system can greatly improve the control accuracy, and has the advantages of small size and light weight compared with motor drive when the required power is the same. Summary of the invention

[0005] The purpose of the present invention is to provide a servo drive scheme for a gas rudder thrust vector device of a plug-type nozzle engine, to select a suitable position for the gas rudder and design a fixing device to fix the rudder blade; to select a reasonable servo control system and design a transmission mechanism to achieve the purpose of controlling the rotation of the rudder blade.

[0006] The technical solution adopted by the present invention to achieve its invention object is:

[0007] The solution includes: gas rudder and its fixing device and integrated electro-hydraulic servo control system. The gas rudder and its fixing device include a plug cone surface, a gas rudder piece, an elliptical connecting boss, a gas rudder shaft, connecting bolts, an angular contact ball bearing, and a bearing fixing cover; the gas rudder servo control system includes an intermediate connecting rod, a hydraulic cylinder, a ball head rod end joint bearing seat, a hydraulic oil tank, a servo motor pump, and an integrated valve block.

[0008] The gas rudder and its fixing device are the controlled objects of the scheme. The gas rudder blade needs to be installed on 50% of the axial length of the truncated plug cone surface to generate sufficient lateral thrust vector force. A boss is manufactured at the corresponding position inside the plug cone to carry the bearing fixing cover; the gas rudder blade adopts a symmetrical hexagonal airfoil with better ablation performance, with a root-tip ratio of 0.4, an aspect ratio of 1.5, a sweep angle of 40°, and a rudder blade thickness of 7% of the average aerodynamic chord length; the gas rudder shaft is arranged at 40% of the root chord length of the gas rudder to reduce the required hinge torque and reduce the power required by the servo system; since the gas rudder blade is large in size, it is inconvenient to extend from the inside of the plug cone, and the gas rudder shaft enters the plug cone from the top of the plug cone, which is not convenient for axial fixation, and a detachable design of the gas rudder shaft and the gas rudder blade is adopted; an elliptical connecting boss is provided as a medium for bolting the gas rudder blade and the gas rudder shaft, The elliptical shape can reduce the thrust loss caused by the boss in the high-temperature and high-pressure gas flow; since the gas rudder blade and the elliptical boss are exposed to the high-temperature and high-pressure gas, and the gas rudder shaft is not in direct contact with the gas, the material performance requirements of the gas rudder shaft can be lower than those of the gas rudder blade, and the split design reduces the cost of materials and processing; in order to realize the axial rotation movement of the gas rudder, an angular contact ball bearing is adopted, and since the connecting rod mechanism will make the gas rudder shaft bear a certain axial force, angular contact ball bearings installed back to back are adopted; in order to realize the axial fixation of the gas rudder, a shoulder is made on the gas rudder shaft to contact the bearing fixing cover and the angular contact ball bearing; a shoulder is made at the junction of the gas rudder shaft and the elliptical connecting boss for placing an O-ring to dynamically seal the high-temperature and high-pressure gas to prevent the gas from entering the gas rudder shaft and the servo control system and causing structural damage.

[0009] The integrated electro-hydraulic servo control system is a power source, and the direct actuator is a hydraulic cylinder. One end of the cylinder is connected to the bearing seat on the surface of the plug cone by a spherical rod end bearing, and the other end is connected to the intermediate connecting rod by a rotating pin. The use of the spherical rod end bearing ensures a small swinging degree of freedom when the cylinder drives the rocker mechanism; one end of the intermediate connecting rod is connected to the hydraulic cylinder by a rotating pin, and the other end is connected to the gas rudder shaft by a bolt pin, transmitting the force from the hydraulic cylinder to the gas rudder shaft; the pressure reducing valve, the electro-hydraulic servo valve, and the one-way valve are integrated in the integrated valve block, which is fixed above the hydraulic oil tank by screws, and the servo motor pump and its driver are fixed to the sides of the valve block and the oil tank by bolts. The hydraulic oil tank, the integrated valve block, and the servo motor pump are integrated and arranged on the surface of the plug cone and are relatively stationary with the plug cone; the high-pressure oil and the low-pressure oil flow into the oil inlet and return port on the hydraulic cylinder through the oil outlet of the integrated valve block.

[0010] Compared with the prior art, the advantages of the present invention are:

[0011] (1) The use of a detachable form to fix the gas rudder blade and the gas rudder shaft can reduce the difficulty of fixing the gas rudder shaft, and is easy to process and assemble. The split design allows the gas rudder shaft and the gas rudder blade to be made of different materials to reduce material costs.

[0012] (2) The gas rudder is subjected to axial load balance and dynamic sealing. Angular contact ball bearings installed back to back are used to bear the axial force of the gas rudder shaft. O-rings are used to seal the high-temperature and high-pressure gas to prevent structural damage, making the solution highly reliable.

[0013] (3) An electro-hydraulic servo system and a planar double rocker mechanism are used to control the rotation of the gas rudder. The double rocker mechanism has a simple and reliable connection and is easy to process and manufacture. The electro-hydraulic servo system has the advantages of high control accuracy, fast response, small size and light weight at high output power.

[0014] (4) The electro-hydraulic servo system adopts an integrated design, integrating the hydraulic cylinder, integrated valve block, servo motor pump and its driver into one, effectively reducing the installation volume of the servo actuator. Each gas rudder has an independent actuator, which can achieve independent deflection, thereby improving the freedom of thrust vector control.

[0015] (5) The gas rudder and the servo control system form an integral unit. The unit design facilitates adaptation to engines with different numbers of gas rudders, making the solution universal. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Axonometric view of the thrust vectoring device of a gas rudder for a plug-type nozzle engine (12 rudder blades)

[0017] 1-engine outer shell, 2-inner nozzle, 3-truncated plug cone, 4-gas rudder

[0018] Figure 2 Cross-sectional view of the gas rudder and its fixing device (12 rudder blades)

[0019] 3-truncated plug cone surface, 4-gas rudder blade, 5-integrated electro-hydraulic servo system, 6-elliptical connecting boss, 7-O-ring, 8-angular contact ball bearing, 9-gas rudder shaft, 10-bearing fixing cover, 11-intermediate connecting rod, 12-rotating pin, 13-bolt pin.

[0020] Figure 3 Integrated electro-hydraulic servo system and connection structure diagram

[0021] 4-gas rudder blade, 6-elliptical connecting boss, 8-angular contact ball bearing, 11-intermediate connecting rod, 501-hydraulic cylinder, 502-hydraulic pipeline, 503-integrated valve block, 504-hydraulic oil tank, 505-servo motor pump and its driver DETAILED DESCRIPTION

[0022] The present invention will be further described in detail below in conjunction with the accompanying drawings and implementation guidelines.

[0023] Figure 1 It is shown that a specific embodiment of the present invention is that the present invention discloses a servo drive scheme for a gas rudder thrust vector device of a plug-type nozzle engine, the axonometric diagram of the device comprises an engine outer shell (1), an inner nozzle (2), a shortened plug cone profile (3), and a gas rudder blade (4); the plug-type nozzle engine comprises an engine outer shell (1), an inner nozzle (2), and a shortened plug cone profile (3); the gas rudder blade (4) is evenly distributed on the shortened plug cone profile (3) in the circumferential direction, the gas rudder shaft is located at 40% of the front of the aerodynamic chord length of the gas rudder blade (4), and the gas rudder blade can independently perform rotational movement around the gas rudder shaft.

[0024] Figure 2The invention is a cross-sectional view of a gas rudder and a fixing device thereof according to an embodiment of the present invention. The angular contact ball bearing (8) is installed on the back of the plug cone surface (3) in a back-to-back manner. A certain gap should be left between the angular contact ball bearing (8) and the back of the plug cone surface (3) to prevent the bearing from getting stuck due to the inner diameter of the bearing being attached to the wall of the plug cone. The shoulder of the gas rudder shaft (9) is axially positioned with the angular contact ball bearing (8). The bearing fixing cover (10) is screwed to the back of the plug cone surface (3) to completely fix the gas rudder shaft (9) axially. , retaining circumferential freedom; the O-ring (7) blocks high-temperature gas from entering the bearing fixing cover (10) to prevent structural damage; the elliptical boss (6) is connected to the gas rudder shaft (9) through bolts from above the plug cone surface, and the gas rudder blade (4) is further connected to the elliptical boss (6) through bolts, thereby fixing the gas rudder blade (4) and the gas rudder shaft (9); the intermediate connecting rod (11) is connected to the gas rudder shaft (9) through a threaded pin (13), and the other end is connected to the hydraulic cylinder through a rotating pin (12).

[0025] Figure 3 The invention is a schematic diagram of an integrated electro-hydraulic servo system and a connection structure, wherein a hydraulic oil tank (504) is connected to a boss on the back of a plug cone surface (3) by means of threads; an integrated valve block (503) is connected to the bottom of the hydraulic oil tank (504) by means of threads; a servo motor pump and a driver (505) thereof are connected to the sides of the integrated valve block (503) and the hydraulic oil tank (504) by means of threads; a hydraulic oil pipeline (502) connects a hydraulic oil cylinder (501) and the integrated valve block (503) for conveying hydraulic oil; one end of the hydraulic oil cylinder (501) is fixed to the boss on the back of the plug cone surface (3) by means of a spherical rod end bearing to ensure a certain amount of swing required when the hydraulic oil cylinder (501) is used as an active rocker, and the other end is connected to an intermediate connecting rod (11) by means of a rotating pin (12).

[0026] After receiving the instruction, the servo motor pump and its driver (505) drive the valve block to move and pump the hydraulic oil to the hydraulic cylinder (501), thereby generating a corresponding action. When the hydraulic cylinder is extended, the hydraulic cylinder (501) drives the intermediate connecting rod (11) to swing clockwise. Under the action of the threaded pin (13), the intermediate connecting rod (11) drives the gas rudder shaft (9) to rotate clockwise. The hydraulic cylinder (501) can feed back the cylinder extension amount at this time to the driver through a displacement sensor for closed-loop feedback adjustment, thereby accurately controlling the cylinder to reach a specified extension amount.

Claims

1. Aiming at the working requirements of the gas rudder thrust vector device of the plug nozzle engine, the present invention proposes a servo drive scheme for the gas rudder thrust vector device of the plug nozzle engine. The characteristics are: The external shape of the scheme comprises an engine outer shell (1), an inner nozzle (2), a shortened plug cone profile (3), and a gas rudder blade (4), wherein the gas rudder blade (4) is evenly distributed at 50% of the plug cone profile (3) in the circumferential direction. The gas rudder and its fixing device comprise an elliptical connecting boss (6), an O-type sealing ring (7), an angular contact ball bearing (8), a gas rudder shaft (9), a bearing fixing cover (10), an intermediate connecting rod (11), a rotating pin (12), and a bolt pin (13); the angular contact ball bearing (8) and the bearing fixing cover (10) axially fix the gas rudder shaft and bear the axial load; the rotating pin (12) and the bolt pin (13) are respectively connected to the hydraulic cylinder (501) and the intermediate connecting rod (11) to form a rod-to-rod connection; the O-type sealing ring (7) seals the gas to prevent structural damage; The integrated electro-hydraulic servo system comprises a hydraulic cylinder (501), a hydraulic pipeline (502), an integrated valve block (503), a hydraulic oil tank (504), a servo motor pump and a driver (505); the integrated valve block (503), the hydraulic oil tank (504), the servo motor pump and a driver (505) are fastened as a whole to a boss on the back of a plug cone surface (3) through threads, and the hydraulic cylinder (501) is fixed to the boss on the back of the plug cone surface (3) through a spherical rod end bearing; the hydraulic cylinder (501) and the integrated valve block (503) are connected through a hydraulic pipeline (502).

2. The gas rudder and the fixing device thereof according to claim 1, characterized in that: The gas rudder blade (4) and the gas rudder shaft (9) are of detachable split design, with an elliptical connecting boss (6) as a transition in the middle; the gas rudder blade (4) and the elliptical connecting boss (6) are installed from the top of the plug cone, and the gas rudder shaft (9) is installed from the bottom of the plug cone; the axial fixing sequence of the gas rudder shaft (9) is: first install the angular contact ball bearing (8), then install the gas rudder shaft (9), and finally install the bearing fixing cover (10). This installation method avoids the axial fixing problem that is more difficult in the integrated design, and allows the gas rudder shaft to use materials with lower thermal protection requirements than the gas rudder blade, thereby reducing production costs.

3. The integrated electro-hydraulic servo system according to claim 1, characterized in that: A planar double rocker mechanism is used to convert the linear motion of an electro-hydraulic servo hydraulic cylinder into a rotational motion for controlling the deflection of a gas rudder; the hydraulic cylinder (501) is connected to the back of a plug cone surface (3) via a spherical rod end bearing; the hydraulic cylinder (501) forms a rotation pair with an intermediate connecting rod (11) via a rotating pin (12); the intermediate connecting rod (11) is fixedly connected to a gas rudder shaft (9) via a screw pin (13); the transmission form is simple and the reliability is high.

4. The integrated electro-hydraulic servo system according to claim 1, characterized in that: The integrated valve block (503), the hydraulic oil tank (504), the servo motor pump and its driver (505) are integrated into a whole by bolts, and the hydraulic oil cylinder (501) is fixed separately on the back of the plug cone surface (3) to form an electro-hydraulic servo system unit to control the deflection of a gas rudder. The integrated design is conducive to saving space. The unit control method can make the control scheme adapt to different numbers of gas rudder blades and make each rudder blade deflect at different angles, thereby improving the applicability of the scheme and the degree of freedom of thrust vector control.

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