An axisymmetric nozzle control mechanism

Abstract

The application belongs to the field of aero-engine, and particularly relates to a kind of axisymmetric nozzle control mechanism, which is circumferentially installed with multiple actuating cylinders outside, and the actuating shafts of the actuating cylinders are all hinged to the same adjusting ring; the rear end of the cylinder body is hinged to circumferentially distributed converging adjusting pieces, and the rear end of each converging adjusting piece is hinged to an expanding adjusting piece; the converging adjusting pieces are hinged to the adjusting ring through converging pull rods, multiple fixed pull rods are circumferentially hinged to the outside of the cylinder body, the fixed pull rods are hinged to the same supporting ring, the rear end of the expanding adjusting piece is hinged to an outer adjusting piece through a cylindrical pair, the other end of the outer adjusting piece is hinged to the supporting ring, and the expanding adjusting piece is hinged to the supporting ring through expanding pull rods; the application can realize synchronous control of the nozzle, and has simple structure and saves space.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of aero-engine, and particularly relates to a control mechanism of an axisymmetric nozzle. BACKGROUND

[0002] The axisymmetric convergent-divergent nozzle has good thrust characteristics, and is still the most commonly used type of nozzle. The inner flow surface of the nozzle is a convergent-divergent surface, which is composed of movable adjusting pieces and sealing pieces. An actuating system changes the opening of the adjusting pieces / sealing pieces in the convergent section and the adjusting pieces / sealing pieces in the divergent section through an adjusting mechanism, thereby adjusting the throat area and the exit area. There are many schemes for the actuating system and the adjusting mechanism of the adjustable axisymmetric convergent-divergent nozzle. The selection of the scheme depends on the requirements of the aircraft and the engine for the performance parameters of the nozzle, the limitation of the maximum outer dimension, the traditional mature design method, and the maturity of the accessories of the actuating system. Basically, the schemes can be divided into two categories. One category is double-ring adjustment, that is, the nozzle has two sets of actuating systems to adjust the throat area and the exit area respectively. The other category is single-ring adjustment, that is, the adjustment of the throat area and the exit area shares one set of actuating system. The nozzle with the single-ring adjustment scheme has only one set of actuating system, which is mainly used for adjusting the throat area. The exit area is generally determined by mechanical positioning or a combination of mechanical positioning and aerodynamic positioning. The mechanical positioning of the exit area is realized by a set of four-bar linkage mechanism composed of the divergent section, the convergent section, and the pull rod. When the throat area is adjusted, the exit area also changes accordingly. In the design, the linkage mechanism must be optimized to take into account all flight states and maintain high thrust characteristics in the main states. The advantage of this way is that the structure and adjustment are simple, and the weight is relatively light.

[0003] The actuating system of the axisymmetric nozzle is usually placed on the thrust cylinder. The actuating system is uniformly arranged on the cylinder in the circumferential direction, which occupies a long axial space of the cylinder. The conventional thrust cylinder has a relatively long axial length, and has a relatively abundant space for the arrangement of the nozzle actuating system. However, with the increasing complexity of the engine functions and the increasing number of adjustable structures, other flow area adjusting mechanisms also need to be arranged on the thrust cylinder. Therefore, it is urgent to propose a more simple control mechanism of the axisymmetric nozzle to meet the new requirements. At the same time, with the increasing requirement of lightweight of the aero-engine, the demand for the nozzle control mechanism with simple structure and lighter weight is more urgent. In addition, the connection between the traditional actuating cylinder and the adjusting piece may cause asynchronization or the actuating cylinder may lose power, resulting in individual failure of the adjusting piece, which will affect the normal flight of the aircraft. SUMMARY

[0004] In order to solve the above problems, the present application provides a control mechanism of an axisymmetric nozzle, characterized in that it comprises:

[0005] The outer side of the barrel is circumferentially provided with a plurality of actuating barrels, and the actuating shafts of the actuating barrels are all hingedly connected to the same adjusting ring; the rear end of the barrel is hingedly connected with circumferentially distributed converging adjusting pieces, and the rear end of each converging adjusting piece is hingedly connected with an expanding adjusting piece; the expanding adjusting piece is hingedly connected with the adjusting ring through an expanding pull rod, and the converging adjusting piece is hingedly connected with the adjusting ring through a converging pull rod, a rocker arm and a short pull rod connected in sequence; the rocker arm is further hingedly connected with the barrel through a support; the rear end of the expanding adjusting piece is hingedly connected with an outer adjusting piece through a cylindrical pair; the outer side of the barrel is circumferentially provided with a plurality of fixed pull rods, and the fixed pull rods are hingedly connected to the same support ring; the rear end of the expanding adjusting piece is hingedly connected with an outer adjusting piece through a cylindrical pair, and the other end of the outer adjusting piece is hingedly connected with the support ring.

[0006] Preferably, the edges of adjacent two outer adjusting pieces are arranged in a stacked manner.

[0007] Preferably, the rear ends of the expanding adjusting pieces and the outer adjusting pieces are sawtooth-shaped.

[0008] Preferably, the number of the actuating barrels is 0.1-0.5 times the number of the converging adjusting pieces.

[0009] Preferably, the actuating barrels are arranged at equal intervals along the circumference of the barrel.

[0010] Preferably, each converging adjusting piece is provided with a converging segment limiter between the included angle with the converging pull rod, and the converging segment limiter is in contact with the converging adjusting piece and the converging pull rod after reaching a preset angle, thereby achieving limiting.

[0011] Preferably, each expanding adjusting piece is provided with an expanding segment limiter between the expanding adjusting piece and the expanding pull rod, and the expanding segment limiter is in contact with the expanding adjusting piece and the expanding pull rod after reaching a preset angle, thereby achieving limiting.

[0012] Preferably, the edges of adjacent two converging adjusting pieces and adjacent two expanding adjusting pieces are stacked with each other.

[0013] Preferably, the edges of adjacent two converging adjusting pieces and adjacent two expanding adjusting pieces are provided with sealing pieces.

[0014] Preferably, the fixed pull rods are hingedly connected along the radial direction of the barrel, and have a degree of freedom of rotation along the radial direction of the barrel.

[0015] The advantages of the present application include: through the circumferentially uniform arrangement of multiple actuating cylinders, multiple forces are linked into a unified and synchronized force through an adjusting ring, which can avoid the situation that an individual adjusting sheet cannot operate normally due to an unexpected situation of the actuating cylinder, and in the actual process, the adjusting sheets produce different adjusting sheet motion effects under the same actuating cylinder due to individual differences, the support ring can unify the force size, and still can be used normally when an individual actuating cylinder is drummed. Reduce the number of actuating cylinders, save the space occupied by the thrust cylinder of the nozzle actuating system; reduce the number of actuating cylinder connecting pipelines, improve the assembly; simplify the nozzle control mechanism, reduce the number of parts, and make the nozzle lighter.

[0016] By circumferentially installing multiple fixed pull rods, the support ring is connected, the fixed pull rod has the freedom of rotating along the radial direction of the cylinder, so that the support ring forms a fixed annular support, the thrust received by the support ring can be changed into compressive stress of the fixed pull rod, and damage caused by shear stress can be reduced; meanwhile, when the support ring receives tensile stress from the pull rod, the tensile stress can form compressive stress inside the support ring.

[0017] The adjustable pull rod is hinged to the adjusting ring, the relative motion between the expansion adjusting sheet and the outer adjusting sheet is adjusted through the cylindrical pair, the expansion pull rod, the expansion adjusting sheet and the outer adjusting sheet constitute a planar four-bar mechanism, the planar four-bar mechanism can more effectively output torque and control the length relationship and motion relationship of the adjusting sheet, meanwhile, the adjusting ring is hinged to the rocker arm, the rocker arm is hinged to the short pull rod, the short pull rod is hinged to the converging adjusting sheet, the rocker arm is hinged to the cylinder to bear the transverse force formed in the motion process, and the thrust of the actuating cylinder is changed into a force perpendicular to the converging adjusting sheet, so that the size of the pressure angle is greatly reduced, and the stress efficiency of the converging adjusting sheet is improved. BRIEF DESCRIPTION OF DRAWINGS

[0018] Fig. 1 is a schematic view of an axisymmetric nozzle control mechanism;

[0019] Fig. 2 is a schematic view of an axisymmetric converging-diverging nozzle structure;

[0020] Fig. 3 is a schematic view of an axisymmetric converging-diverging nozzle structure;

[0021] Fig. 4 is a schematic view of an axisymmetric converging-diverging nozzle structure;

[0022] Wherein, 1-cylinder; 2-actuator cylinder mounting seat; 3-actuator cylinder; 4-adjusting ring; 5-bracket; 6-rocker arm; 7-short pull rod; 8-converging pull rod; 9-expanding pull rod; 10-converging adjusting piece; 11-expanding adjusting piece; 12-outer adjusting piece; 13-converging sealing piece; 14-expanding sealing piece; 15-converging section limiter; 16-expanding section limiter; 17-expanding section limiter; 18-support ring; 19-fixed pull rod. A-outer adjusting piece hinge point; B-expanding pull rod hinge point; C-short pull rod hinge point. DETAILED DESCRIPTION

[0023] To make the purposes, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described in more detail below with reference to the drawings in the embodiments of the present application. Identical or similar reference numerals are used to represent identical or similar elements or elements with identical or similar functions throughout the drawings. The described embodiments are part of the embodiments of the present application, rather than all the embodiments of the present application. The embodiments described below with reference to the drawings are exemplary and are intended to explain the present application, and cannot be understood as a limitation on the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of protection of the present application. The embodiments of the present application will be described in detail below with reference to the drawings.

[0024] As shown in Figs. 1-4 1, the structure of the axisymmetric converging-diverging nozzle is determined; the axisymmetric converging-diverging nozzle mainly includes a cylinder 1, an actuator cylinder mounting seat 2, an actuator cylinder 3, an adjusting ring 4, a bracket 5, a rocker arm 6, a short pull rod 7, a converging pull rod 8, an expanding pull rod 9, a converging adjusting piece 10, an expanding adjusting piece 11, an outer adjusting piece 12, a converging sealing piece 13, an expanding sealing piece 14, a converging section limiter 15, an expanding section limiter 16, an expanding section limiter 17, a support ring 18, and a fixed pull rod 19.

[0025] The number of the cylinder 1, the adjusting ring 4, and the support ring 18 is one; the number of the actuator cylinder mounting seat 2 and the actuator cylinder 3 is three, which are arranged uniformly in the circumferential direction; the number of the bracket 5, the rocker arm 6, the short pull rod 7, the expanding pull rod 9, the converging adjusting piece 10, the expanding adjusting piece 11, the outer adjusting piece 12, the converging sealing piece 13, the expanding sealing piece 14, the converging section limiter 15, the expanding section limiter 16, the expanding section limiter 17, and the fixed pull rod 19 is fifteen, which are arranged uniformly in the circumferential direction; the number of the converging pull rod 8 is thirty.

[0026] The movement principle of the nozzle control mechanism is as follows: the actuating cylinder drives the adjusting ring, the adjusting ring drives the short pull rod, the short pull rod drives the rocker arm, the rocker arm drives the converging pull rod, and the converging pull rod drives the converging adjusting piece to move, so as to realize the adjusting control of the throat area of the nozzle; the expanding pull rod is hinged at one end to the supporting ring and at the other end to the expanding adjusting piece, and the expanding adjusting piece follows the converging adjusting piece to move, so as to realize the adjusting of the outlet area; the outer adjusting piece is slidably connected at one end to the expanding adjusting piece and hinged at the other end to the supporting ring, and the outer adjusting piece moves with the movement of the expanding adjusting piece.

[0027] In order to improve the radar stealth performance, the expanding adjusting piece and the outer adjusting piece are designed with sawtooth profile at the outlet; the outer adjusting piece is designed with overlapping between two adjacent pieces;

[0028] The converging sealing piece is arranged between two adjacent converging adjusting pieces, and the stopper on the converging sealing piece is hung on the two adjusting pieces to limit the movement; the expanding sealing piece is arranged between two adjacent expanding adjusting pieces, and the stopper on the expanding sealing piece is hung on the two expanding adjusting pieces to limit the movement;

[0029] The rocker arm is fixed through the bracket, one rocker arm is connected with two converging pull rods, and the two converging pull rods are connected with adjacent converging adjusting pieces respectively; this scheme makes one rocker arm of the cylinder drive the adjacent converging adjusting pieces to move, and the bracket limits the movement of the rocker arm to rotation only, so that the scheme has strong mechanical synchronization function;

[0030] The load of the outer adjusting piece can be effectively transmitted to the cylinder through the supporting ring, so that the load of the adjusting ring is only affected by the inner flow load, the load of the actuating cylinder is more single, and the control reliability of the actuating cylinder can be effectively improved. The design of the adjusting ring is affected by the inner load only, the design variable of the structure is reduced, and the design difficulty is reduced.

[0031] Through the plurality of actuating cylinders arranged uniformly in the circumferential direction, the plurality of forces are linked into a unified and synchronous force through one adjusting ring, so that the individual adjusting piece cannot operate normally under the unexpected condition of the actuating cylinder, and in the actual process, the adjusting pieces have different movement effects under the same actuating cylinder due to individual differences, the supporting ring can unify the force, and the individual actuating cylinder can still be used normally when the actuating cylinder is drummed. The number of actuating cylinders is reduced, the space occupied by the actuating system of the nozzle for the booster cylinder is saved; the number of connecting pipelines of the actuating cylinder is reduced, the assembly is improved; the nozzle control mechanism is simplified, the number of parts is reduced, and the weight of the nozzle is lighter.

[0032] The support ring is connected by circumferentially installing a plurality of fixed pull rods, the fixed pull rods have the freedom of rotating along the radial direction of the cylinder, so that the support ring forms a fixed annular support, the thrust received by the support ring is changed into compressive stress of the fixed pull rods, and damage caused by shear stress is reduced; meanwhile, when the support ring receives tensile stress from the pull rods, the tensile stress can form compressive stress inside the support ring.

[0033] The adjustable pull rod is hinged with the adjusting ring, the relative movement between the expansion adjusting piece and the outer adjusting piece is adjusted through the cylindrical pair, the expansion pull rod, the expansion adjusting piece and the outer adjusting piece are expanded, a planar four-bar mechanism is formed, the planar four-bar mechanism can more effectively output torque and control the length relationship and movement relationship of the adjusting pieces, meanwhile, the adjusting ring is hinged with the rocker arm, the rocker arm is hinged with the short pull rod, the short pull rod is hinged with the converging adjusting piece, the rocker arm is hinged with the cylinder to bear the transverse force formed in the movement process, and the thrust of the actuator is changed into a force perpendicular to the converging adjusting piece, so that the size of the pressure angle is greatly reduced, and the stress efficiency of the converging adjusting piece is improved.

[0034] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited to this, any person skilled in the art can easily think of changes or replacements within the technical range disclosed in the present application, which should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A control mechanism for an axisymmetric convergent-divergent nozzle, characterized by, The utility model relates to a kind of telescopic cylinder, including: Cylinder (1), outside circumferential installation multiple actuator cylinder (3), the actuating shaft of actuator cylinder (3) is hinged to same adjusting ring (4);Cylinder (1) rear end is hinged to multiple circumferential distribution converging adjusting piece (10), and the rear end of each converging adjusting piece (10) is hinged to one expansion adjusting piece (11);Expansion adjusting piece (11) is hinged to support ring (18) by expansion pull rod (9), and converging adjusting piece (10) is hinged to adjusting ring (4) by sequentially hinged converging pull rod (8), rocker arm (6), short pull rod (7), and rocker arm (6) is also hinged to cylinder (1) by support (5), and the outside of cylinder (1) is circumferentially hinged multiple fixed pull rod (19), and fixed pull rod (19) is hinged to same support ring (18), and the rear end of expansion adjusting piece (11) is hinged to outer adjusting piece (12) by cylindrical pair, and the other end of outer adjusting piece (12) is hinged to support ring (18); Each converging adjusting piece (10) and converging pull rod (8) between included angle has converging section limiter (15), and converging section limiter (15) contacts with converging adjusting piece (10) and converging pull rod (8) after reaching preset angle to realize limiting; Each expansion adjusting piece (11) and expansion pull rod (9) between has expansion section limiter (16), and expansion section limiter (16) contacts with expansion adjusting piece (11) and expansion pull rod (9) after reaching preset angle to realize limiting; The edge of adjacent two converging adjusting pieces (10) and the edge of adjacent two expansion adjusting pieces (11) are arranged in laminated manner;Converging section limiter (15) on the sealing piece is hung on the two converging adjusting pieces (10) to limit.

2. The axisymmetric diverging nozzle control mechanism of claim 1, wherein The edges of adjacent two outer adjusting pieces (12) are arranged in laminated manner.

3. The axisymmetric diverging nozzle control mechanism of claim 1, wherein The rear end of expansion adjusting piece (11) and outer adjusting piece (12) is sawtoothed.

4. The axisymmetric diverging nozzle control mechanism of claim 1, wherein The number of actuator cylinder (3) is 0.1-0.5 of the number of converging adjusting piece (10).

5. The axisymmetric diverging nozzle control mechanism of claim 1 wherein, Actuator cylinder (3) is arranged equidistantly along the circumference of cylinder (1).

6. The axisymmetric diverging nozzle control mechanism of claim 1 wherein, The edges of adjacent two converging adjusting pieces (10) and the edges of adjacent two expansion adjusting pieces (11) are arranged in laminated manner.

7. The axisymmetric diverging nozzle control mechanism of claim 1 wherein, Fixed pull rod (19) is hinged along the radial direction of cylinder (1), and has the freedom of rotating along the radial direction of cylinder (1).

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