CN1080375C - Axisymmetric vectoring nozzle actuating system having multiple power control circuits - Google Patents

Abstract

A nozzle failure protection actuation system (2) for an axisymmetric directional exhaust nozzle (14) of an aircraft gas turbine, having a directional ring (86) operably connected to a plurality of rotating hinges (50) , these hinges are arranged circumferentially around the nozzle centerline (8) and define the exhaust flow path in the nozzle (14). The nozzle failure protection actuation system (2) has at least two independently operable first and second directional actuation systems (2A and 2B), including first and second directional actuation systems operatively connected to the directional ring (86). A second set of operators (90A and 90B) and first and second failsafe controls respectively control power to the first and second actuators (90A and 90B). A first set of directional actuators is combined with a second set of second directional actuators arranged around the nozzle (14). The first of the two sets of actuators is operative to drive the nozzle (14) when one is fail-safe.

Description

Axisymmetric directional nozzle actuation system with multiple power control loops

This invention relates generally to gas turbine axisymmetric directional exhaust nozzles, and more particularly to the actuation systems of these engines with multiple power circuits of control directional loops.

Military aircraft designers and engineers are continually working to improve the aircraft's maneuverability for both air-to-air combat missions and complex ground attack missions. They have improved thrust directional nozzles that turn or orient the exhaust flow and the thrust of the gas turbine that drives the aircraft to replace or augment the use of conventional aerodynamic surfaces such as flaps and ailerons. A new and improved thrust directional nozzle is an axisymmetric vectored exhaust nozzle disclosed by Hauer in US 4,994,660, incorporated herein by reference. The axisymmetrically oriented exhaust nozzle provides a A device for directing the thrust of an axisymmetric contraction/expansion nozzle. These hinges are rotated by means of an orienting ring which can be displaced axially and gimbaled or swung through a limited range about its horizontal and vertical axes (so that its attitude is substantially corrected).

The axisymmetrically oriented exhaust nozzle, like the more conventional gas turbine exhaust nozzle, also includes primary and secondary exhaust flaps, which are arranged to define a variable area constriction-expansion exhaust nozzle. The exhaust nozzle is generally axisymmetric or circular, and the exhaust flow is closed up to the throat of the nozzle with primary or constricting flaps and then closed with secondary or expanding flaps. The expanding flaps, for example, have a forward end having a throat defining a minimum flow area and a rear end having a larger flow area defining a expanding nozzle extending downstream from the throat. The expansion flaps are variable, which means that the space between the expansion flaps necessarily increases as they move from a smaller radius position to a more radial position. Accordingly, the exhaust nozzle seal is suitably secured between adjacent expanding flaps to seal off the exhaust flow and prevent leakage of the exhaust flow between the expanding flaps.

Oriented nozzles, especially the axisymmetrically oriented exhaust nozzles disclosed in the Hauer reference, provide positionable expansion flaps. The expansion flaps may be positioned not only symmetrically but also asymmetrically with respect to the longitudinal centerline of the exhaust nozzle to achieve pitch and roll orientations. The axisymmetric directional exhaust nozzle disclosed by Hauer in US 4,994,660 employs three directional actuators to move and oscillate a directional ring which in turn forces the expanding flaps in predetermined positions. The orientation ring swing angle and swing direction respectively establish the orientation angle and orientation direction of the nozzle. Axial movement of the directional ring defines the outlet area (often called A9) for a given throat area (often called A8).

Modern multi-mission aircraft use engines such as the GE110 with retracting/expanding nozzles to meet operational needs. The converging/expanding nozzle has a converging region, a throat and a diverging region in sequential flow relationship. These nozzles are characterized by variable area devices at their throats and outlets. This provides a means of maintaining the desired ratio of outlet to throat area which in turn allows efficient control of nozzle operation. The purpose of operating the nozzle is to provide a range of nozzle exit/throat area (A9/A8) that is optimized for the engine design cycle and should theoretically provide effective control for low subsonic and high supersonic conditions. These nozzles typically employ pneumatic or hydraulic actuators to provide variable operation. Typically, the outlet and throat areas are mechanically matched to each other in such a way as to establish an area ratio (A9/A8) as a function of the nozzle throat area (A8). Thrust directional nozzles generally have the ability to independently control nozzle exit area and throat area, which allows the engine to achieve high performance standards over its wide operating range.

During engine operation and aircraft flight, the hydraulic actuation system of the nozzle may fail in one or more of several conditions due to component failure or damage, such as due to combat. This failure may be a mechanical failure or a control system failure, which is typically detected by the flight control computer and/or the directional electronic controller used as the thrust directional nozzle. This nozzle actuation system has a hydraulic fail-safe position which utilizes a directional ring actuator to fully retract and in the case of the directional ring, sets the nozzle in a fixed unoriented position so that the engine's Thrust is not directed. These directional actuators are also used to control the A9. However, the resulting nozzle geometry has a large area ratio (A9/A8) which prevents the opening of A8 and thus the operation of the booster and is therefore not aerodynamically optimal. This failsafe system is no good in combat. This large area ratio also enables separation of the exhaust plume in the nozzle expansion region. In particular, intermittent separation and recombination of the exhaust flow in an asymmetrical pattern relative to the engine centerline can result in an unintentional directional force. Fully opening the diversion of the nozzle results in very different nozzle kinematics, while opening the nozzle throat at such a high area ratio can seriously damage the nozzle. The inability to open the throat of the nozzle prevents the normal operation of the engine under ground conditions and when operating in the afterburner mode, which can make the operation of the aircraft deviate from the normal state.

These disadvantages are overcome by U.S. Patent Application Serial No. 08/314,124, filed September 29, 1994, which discloses a method that enables the nozzle to operate safely when certain types of hydraulic systems fail. A fail-safe mechanism whose mode of operation is rapidly formed so that the fail-safe system can operate with minimal adverse effects on the overall operability of the aircraft and its engines, especially during combat. However, the nozzle could no longer direct the thrust, which was a significant disadvantage during combat operations.

A significant disadvantage inherent in the three-actuator scheme is the large span between any two actuators for a given secondary ring size. Beam Theoretical Engineering stipulates that the deflection of a simply supported beam is proportional to the first power of the load, proportional to the third power of the span, and inversely proportional to the stiffness. In other words, for a given load and stiffness, doubling the span increases deflection eightfold (23). The three-actuator solution for the directional nozzle creates the longest possible span between the two actuators and, therefore, requires the greatest possible stiffness, resulting in a heavy secondary actuation ring to maintain the A given minimum acceptable deflection value.

Deflection of the actuator ring is undesirable because it can unload the expansion system of the directional nozzle toward a non-directional state, thereby reducing directional performance. Maximizing the cross-section and utilizing internal ribs to control the distributed load path, as described in PCT WO 98/20245, published May 14, 1998, reduces deflection. Another inherent disadvantage of the three-actuator scheme of the directional nozzle system is that failure of the actuation system can negatively affect the flight of the aircraft. Three actuators are the least required to maintain the secondary ring at a fixed position and swing angle. In the event of an actuator failure (eg, hydraulic failure), the ring swing is no longer restricted and an uncontrolled exhaust positioning may occur. The occurrence of this situation is highly undesirable.

The incidence of directional ring actuation system failures can be reduced to a practical level by adding precautionary measures, including installing duplicate components in a structure so that the failure of any one component does not lead to failure of the entire actuation system. These precautions add to the cost, complexity and weight of the system. Another approach to preventing failure of the directional ring actuation system is to use reactive measures to control the occurrence of the failure, which may include adding components to detect the failure and then actively position the ring into a fail-safe position. All of these solutions add cost to the system. Complexity and weight, they all center the swing of the secondary ring to an intermediate position, thereby eliminating all directional capability of the directional exhaust nozzle system. Eliminating thrust orientation is particularly detrimental if the aircraft system intends to utilize thrust orientation for short takeoffs or landings, as may be required due to combat damaged runways or aircraft carrier operations or in combat situations. Therefore, it is highly desirable to have an axisymmetric directional exhaust nozzle that has a hydraulic fail-safe system that minimizes the load on the directional ring for the nozzle outlet/throat area ratio (A9 /A8) provides control. And in one embodiment, when a fault occurs within the actuation system, it enables the nozzle to direct thrust without causing the entire actuation system to fail.

The invention provides a fail-safe nozzle actuation system for an axisymmetric directional exhaust nozzle of an aircraft gas turbine. Rotating flaps of the exhaust runner in the nozzle. The fail-safe nozzle actuation system has a first directional actuation system with a first set of actuators operably connected to the directional ring, and a first fail-safe control output to the first set of actuators control device. There is also a second directional actuation system with a second set of actuators operably connected to the directional ring and a second failsafe control device for controlling power delivery to the second set of actuators. The first set of actuators is arranged alternately with the second set of actuators around the nozzle.

The preferred embodiment provides two sets of actuators and two corresponding directional actuation systems, each with a set of three failsafe actuators. However, the present invention includes the use of two or more actuators with two or more corresponding directional actuation systems. The preferred embodiment of the failsafe nozzle actuation system is hydraulically actuated.

A more specific embodiment provides a single hydraulic power source, in the form of an engine mounted and driven hydraulic pump, in hydraulic power source communication with each of the first and second sets of actuators and corresponding failsafe controls operate. Alternatively, two hydraulic pumps installed and driven by the engine are used as the first and second hydraulic power sources, and they each only generate corresponding hydraulic power with one of the first and second groups of actuators and the corresponding fail-safe control device source connectivity. One of the two pumps may also be an aircraft hydraulic pump, which is also used to power the aircraft hydraulic system. Alternatively, two hydraulic pumps of the aircraft may be used as the first and second hydraulic power sources, each of which communicates with only one of the first and second sets of actuators and the corresponding fail-safe device respectively as a corresponding hydraulic power source.

Another embodiment of the invention provides two sets of actuators and two sets of corresponding directional actuation systems, each having a set of two fail-safe actuators. However, this embodiment does not provide thrust orientation to the nozzle in failsafe mode, but instead provides nozzle outlet/throat area ratio (A9/A8) control.

A more specific embodiment provides a control system that monitors hydraulic pressure signals from components in an actuation system that includes the control system, and includes a fail-safe mode actuation device that, when the control system detects In the event of a loss of signal (a significant predetermined hydraulic drop), failsafe mode is implemented. The signal generating device may be one or more of the following: flight control computer, directional electronic controller, and hydraulic control switch.

The present invention provides advantages over earlier nozzle configurations by providing the ability to bring a thrust directional nozzle into a fail-safe mode upon a fault or failure signal in the hydraulic actuation system of the nozzle without complete loss of thrust directional capability, This is especially important in combat conditions and minimizes the load on the directional ring. The present invention also provides control of the nozzle outlet/throat area ratio (A9/A8) when the thrust directional nozzle is placed in failsafe mode.

The novel features believed to be characteristic of the invention are defined in the claims. The invention and its other objects and advantages are described in more detail together with the accompanying drawings, in which:

1 is a perspective view of an axisymmetrically oriented exhaust nozzle with a fail-safe nozzle actuation system in accordance with one embodiment of the present invention;

Figure 2 is a schematic perspective view depicting the position of the actuator and orientation ring of the fail-safe nozzle actuation system of Figure 1;

Figure 3 is a schematic diagram of an actuation system according to an embodiment of the present invention;

4 is a schematic diagram of an actuation system according to another embodiment of the present invention;

Figure 5 is a cross-sectional view of an aircraft having an engine and directional nozzle with a failsafe actuation system according to one embodiment of the present invention.

One embodiment of the present invention shown in FIG. 1 is a failsafe nozzle actuation system for an axisymmetric thrust directional nozzle 14 in an aircraft gas turbine engine (not shown in its entirety) exhaust component 10, generally denoted by 2 said. Exhaust assembly 10 contains glowing exhaust gas flow 4 in an exhaust runner generally circumferentially disposed about engine centerline 8 and in sequential flow relationship comprising a fixed area duct or engine casing 11 comprising an afterburner A variable area downstream region 13 of a constricting/expanding axisymmetric thrust directional nozzle 14 of liner 12 similar to that of the previously cited Hauer patent. Referring to FIG. 1, nozzle 14 includes, in sequential flow relationship, a converging region 34, a throat 40 and diverging region 48. The constriction zone 34 includes a number of constriction or main flaps 50 circumferentially disposed about the engine centerline 8 overlapping a primary seal 51 disposed therebetween which is radially inwardly of the circumferentially adjacent main flaps 50 surface into a hermetic joint. Each main hinge 50 is fixed to the casing 11 in a swinging manner by a first pivot joint or a V-shaped hook 52 at its front end. Each expansion hinge 54 is rotationally connected at its front end 53 to the rear end 53 of the main hinge adjacent to the downstream of the main hinge 50 by a conventional two-degree-of-freedom (2 DOF) joint 56 approximately on the axis of the nozzle 14. In the upward position, it coincides with the throat 40 . Expansion flaps 54 are generally circumferentially disposed about engine centerline 8, overlapping with auxiliary or expansion sealing means 55 disposed therebetween, which engage radially inward surfaces or sealing engagements of circumferentially adjacent expansion flaps 54 . When the pressure of the nozzle, the radial inward pressure of the flaps and the sealing device is generally greater than the external pressure of the nozzle, that is, the general ambient atmospheric pressure or the inlet pressure of the nozzle, during the operation of the nozzle, the expansion sealing device 55 is used to seal the expansion Hinge 54. Throat 40 has a throat area, generally designated A8, and nozzle outlet 44, generally at the end of expansion flap 54, has an outlet area, generally designated A9.

A number of cam rollers 62 are disposed in a main ring 66 which in turn is moved back and forth by a number of first nozzle actuators 70, in the preferred embodiment, four actuators. The variable throat area A8 is controlled by the action of a cam roller 62 on a cam surface 60 formed on the back of the main flap 50 . During operation, the exhaust high pressure within the nozzle forces the main flap 50 and the expansion flap 54 radially outward, thereby keeping the cam surface 60 in contact with one of the cam rollers 62 . A conical annular actuator bracket 76 is mounted on the engine housing 11 with its narrow front end, and the first nozzle actuator 70 is rotatably connected to the wide rear end of the actuator bracket 76 through a ball joint 74 . The first nozzle actuator 70 has an actuator rod 73 which in turn is connected to the main ring 66 via a ball joint 68 .

A first set of first directional actuators 90A, in the preferred embodiment three actuators 90A, are equiangularly arranged circumferentially around the housing 11 in the same manner as the first nozzle actuators 70. The way is installed on the actuator bracket 76 through the ball joint 94. A second set of second directional actuators 90B, in the preferred embodiment three actuators 90B, are equiangularly arranged circumferentially about the housing 11, interlaced with the first set of first directional actuators 90A. , is mounted on the actuator bracket 76 via the ball joint 94 in the same manner as the first nozzle actuator 70 . The first and second sets of directional actuators 90A and 90B are offset from each other by an angle A between all adjacent first and second directional actuators 90A and 90B, respectively. In the exemplary embodiment of the invention shown in these figures, there are three first orienting actuators 90A and three second orienting actuators 90B, and the angle A is 60°. The orientation ring 86 is connected to the first and second orientation actuators 90A and 90B respectively via a ball joint 96 with the rear end of the orientation actuator rod 93 of each orientation actuator. This provides axial movement and rotation about the centerline 8 for the orientation ring 86 to control its attitude and its axial movement along the engine centerline 8 . Orientation ring 86 controls the positioning and rotation of expansion flap 54 . The expansion hinge 54 is rotatably connected to the main hinge 50 with a two-degree-of-freedom common joint device 56, and is rotatably controlled in a multi-degree-of-freedom manner by several corresponding Y-shaped frames 59. The Y-shaped frame has control arms 58a and 58b, which operatively connect the orientation ring 86 to the expansion flap 54. Additional flaps 64 are at least partially supported by the Y-shaped frame 59 and form a streamlined, smooth aerodynamic profile along the exterior of the nozzle.

Control arms 58a and 58b are connected to orientation ring 86 by three degree of freedom ball joint 82 and to the rear end of expansion hinge 54 by a ball joint 84 . This connection can convert the attitude change of the orientation ring 86 into a multi-degree-of-freedom rotational change and orbital movement of the expansion hinges 54, whereby each expansion hinge can be rotated through different angles. The use of ball joint 82 connecting control arms 58a and 58b provides for V-hook type rotation of Y-frame 59 while preventing any torsional loads that might be transmitted to control arms 58a and 58b from being transmitted back to retaining ring 86 . Spine 92 at its ends provides support for diffuser flap 54 and provides support for joints 84 and 56 .

The thrust directional nozzle utilizes the axisymmetric positioning of the expansion flap 54 and the sealing device 55 relative to the centerline 8, so that the radial and peripheral positions and attitudes of the expansion flap and the sealing device are axisymmetrically positioned to direct the thrust. Orienting ring 86 is moved and gimbaled about nozzle centerline 8 by three first orienting actuators 90A and three second orienting actuators 90B, which actuators cooperate to orient the thrust and move the orienting force. ring to adjust and/or control the variable outlet area A9 and set the ratio of outlet area to throat area A9/A8. The variable throat area A8 can be independently set by moving the main ring 66 through the first actuator 70, thereby setting the ratio of the outlet area to the throat area A9/A8.

Alternatively, a mix of actuator sets and ring sets is used to set the outlet area to throat area ratio A9/A8. In an emergency situation, when the actuation system 2 is set in fail-safe mode, only the first set of first directional actuators 90A or the second set of second directional actuators 90b are enabled to operate while the others are fail-safe , either set can be used to drive the ring 86 by moving it along the centerline 8 or universally turning it around the centerline 8. The actuation system 2 includes an electronic controller, which can be a separate component or part of the directional electronic controller VEC. The present invention provides a failsafe nozzle actuation system 2 with two individually controlled first and second directional actuation systems 2A and 2B, respectively. The first directional actuation system 2A controls only the first set of first directional actuators 90A, and the second directional actuation system 2B controls only the second set of second directional actuators 90B.

Shown in Fig. 2 is the distribution of the first directional actuator 90A, and the second group of the second directional actuator 90B is arranged in a staggered manner around the nozzle, indicating that each group can be operated while the other The group is fail-safe, the ring 86 is driven by moving it along the centerline 8 or universally turning it around the centerline 8 . Also represented is the advantage of providing a shorter circumferential span S along the ring 86 between the connection point P of the first directional actuator 90A and the second set of second directional actuators 90B to the directional ring. This allows the ring 86 to be thinner and lighter in weight. The size of six actuators is smaller than that required when using three, thus keeping the overall weight of the directional nozzle system to a minimum. A six-actuator system is not only part of a fail-safe system, but its gross weight can even be lower than that of a three-actuator system, which allows at least partial thrust direction in the event of a failure of a set of three-actuator systems in combat.

The present invention provides a fail safe nozzle actuation system 2 having two independently controlled first and second directional actuation systems 2A and 2B, shown in detail in FIG. 3 . The first directional actuator system 2A uses a set of first actuator servo valves to control the actuation of a first directional actuator 90A1, a second directional actuator 90A2 and a third directional actuator 90A3 , the set of first actuator body service valves includes a first actuator service valve 16A1, a second actuator service valve 16A2 and a third actuator service valve 16A3, each of which only controls the orientation A corresponding one of the actuators 90A1-90A3. Similarly, the second directional actuator system 2B uses a set of second actuator servo valves to respectively control the actuation of the fourth, fifth and sixth directional actuators 90B1-90B3 of the second group. The second actuator service valve includes a fourth actuator service valve 16B1, a fifth actuator service valve 16B2 and a sixth actuator service valve 16B3, each of which only controls the fourth and the fourth actuator valves. A corresponding one of the fifth and sixth directional actuators 90B1-90B3. Each group and each of the 3 service valves in each group are independently controllable. Preferably, the service valves in both systems are incorporated into one control valve 3 to minimize the increased number of parts. Alternatively, each set of 3 service valves can be housed in separate control valves, or be grouped into their respective actuators.

The first and second directional actuation systems 2A and 2B have first and second delivery isolation valves 18A and 18B operatively disposed in first and second delivery lines 19A and 19B, respectively, which receive power from a hydraulic power source H, respectively. to the upper portions 20A and 20B of the first and second delivery lines. The first and second directional actuation systems 2A and 2B have first and second return isolation valves 22A and 22B operatively disposed in first and second return lines 23A and 23B, respectively, which are directed away from the first and second return lines 23A and 23B. The direction of the upper part 24A and 24B of the two return lines leads to the hydraulic power source H. This allows the fail-safe nozzle actuation system 2 to isolate the operative directional actuation system 2A or 2B from the rest of the system should a leak or failure be detected in the fail-safe system. A first recirculation valve 26A is operatively disposed between the first transfer line upper portion 20A and the first return line head 24A, thereby providing a flow of hydraulic fluid through the top chamber 28 and rod chamber 30 of the failsafe actuator group. between direct flow devices.

Failsafe The first directional actuation system 2A is accomplished by the failsafe nozzle actuation system 2, which closes the first delivery block valve 18A and the first return isolation valve 22A. The first directional actuation system 2A sets the first set of 3 servo valves 16A1-16A3 respectively in positions that allow hydraulic fluid to flow from the upper upper portion 20A of the first transfer line to the upper chamber 28 through the first set of upper lines 102H , and in the middle of the upper part 24A of the first return line, flow through the rod line 102R to the rod chambers of the first 3 directional actuators 90A1-90A3, thereby providing an upper chamber 28 and rods that allow the hydraulic fluid to fail in the fail-safe group of the actuator A device for direct flow between chambers 30 . The first directional actuation system 2A opens the first recirculation valve 26A to allow hydraulic fluid to flow between the first transfer line upper 20A and the first return line upper 24A.

Likewise, if the second 3-direction actuators 90B1-B3 are instead failsafe, the failsafe nozzle actuator system 2 closes the second delivery isolation valve 18B and the second return isolation valve 22B. The second directional actuation system 2A sets the second set of 3 servo valves 16B1-16B3 in positions that allow hydraulic fluid between the second supply line 20B and the upper chambers 28 and in the second return line, respectively. The flow between the upper portion 24B of the line and each rod cavity 30 of the second 3-direction actuator 90B1-90B3. The second directional actuation system 28 also opens the second recirculation valve 28 to allow hydraulic fluid to flow between the second transfer line upper 20B and the second return line upper 24B.

Another embodiment of the invention with a total of 4 actuators is shown in Figure 4, which provides a fail-safe nozzle actuation system 2, with only two separately controlled first and second directional actuations Systems 2A and 2B, each with only two directional actuators. The first directional actuator system 2A utilizes a first set of actuator servo valves to control the actions of a first directional actuator 90A1 and a second directional actuator 90A2, and the set of servo valves includes a first actuator One actuator servo valve 16A1 and one second actuator servo valve 16A2 each control only a corresponding one of the directional actuators 90A1 and 90A2. Similarly, the second directional actuator system 2B utilizes the second set of actuator servo valves including the third and fourth actuator servo valves 16B1 and 16B2 to respectively control the third and fourth directional actuators 90B1 and 90B2, which each control only a corresponding one of the third and fourth directional actuators 90B1 and 90B2. Each set and each of the 2 service valves in each set are independently controlled. Preferably, the servo valves in the two systems are assembled into one control valve 3 to minimize the increased number of parts. Alternatively, each set of two servo valves can be assembled as a single control valve or incorporated into their corresponding actuators. While this embodiment does not provide nozzle thrust orientation in fail-safe mode, it does allow control of the nozzle exit/throat area ratio (A9/A8) in fail-safe mode, which is applicable to axisymmetric thrust-oriented nozzles 14 Lightweight fail-safe nozzle actuation system.

Various arrangements and positions of the hydraulic pumps are shown in FIG. 5, and the hydraulic pumps supply the first and second directional actuation systems through first and second delivery line uppers 20A and 20B and first and second return line uppers 24A and 24B, respectively. 2A and 2B provide hydraulic power. The engine 130 has an exhaust component 10 and a directional nozzle 14 installed in a military-type aircraft 132 . Also shown in the drawings are first and second orientation actuators 90A and 90B to aid in illustrating exhaust assembly 10 and orientation nozzle 14 . The power shaft 134 driven by the engine rotor 138 extends down from the rotor to the engine gearbox 140 which has right angle gears and drives a power index shaft 142 (PTO) which extends towards the front of the engine 130 . Mounted below the engine 130 are first and second engine mounted hydraulic pumps 146 and 148 respectively, which extend rearwardly from the engine gearbox 140 and are driven by the gearbox. The engine mounted first and second hydraulic pumps 146 and 148 are used to provide hydraulic power to the engine and its accessories. Shaft 134 extends forwardly to drive an auxiliary drive gearbox 150 which in turn has the appropriate gears to drive the various accessories of aircraft 132 . Auxiliary drive gearbox 150 is mounted to aircraft 132 by suitable frame mounts 152 and is connected to the power traction shaft by a misalignment adapter 154 .

Figure 5 illustrates, as an introduction, the respective hydraulic power sources H applicable to the first and second directional actuation systems 2A and 2B. One embodiment of the present invention employs first and second engine mounted hydraulic pumps 146 and 148 to provide hydraulic power source H to first and second directional actuation systems 2A and 2B, respectively. Alternatively, only one of the engine-mounted hydraulic oil pumps can be used as the hydraulic power source H, which merges the first and second transfer lines 19A and 19B into one hydraulic pump at a point between the isolation valves 18A and 18B. The pump and the pipeline of the hydraulic pressure source H in Fig. 3. Likewise, either of the first and second aircraft-mounted hydraulic pumps 156 and 158, which are mounted on and driven by the auxiliary drive gearbox 150, may be used to drive the first and second Directional Actuation Systems 2A and 2B. Alternatively, one of the engine mounted hydraulic pumps and one of the aircraft mounted hydraulic pumps may each be used to drive only one of the directional actuation systems 2A and 2B. The benefits of a staggered arrangement of the hydraulic power to drive and actuate the directional nozzles are evident. Damage sustained in one part of the aircraft can damage one of these pumps, allowing the pump in another part of the aircraft to remain running to drive the directional nozzle.

Returning to Fig. 1, the directional ring 86 is supported by 3 shaft-adjustable directional ring supporting devices 100 disposed around the housing 11 at equal angles along the circumference, which allows the fixed ring 86 to move axially and is controlled by the directional actuators 90A and 90B. Universal rotation. An axially movable A-bracket 210 supports the orientation ring 86 via a 3DOF ball joint 206 . The A-frame 210 is rotatably connected to a slider 220 at the ends of arms 211a and 211b by a fork head hinge arrangement 208 in the form of a ball joint. The use of ball joints at the ends of the arms 211a and 211b provides fork head rotation of the A-bracket 210 and also eliminates the transfer of torsional loads that might be transferred to these arms. The slider 220 can slide along the hollow slider rod 226 , and the slider rod is connected to the engine casing 11 by the front bracket 236 and the rear bracket 230 . The directional ring supporting device 100 allows the directional ring 86 to move axially forward and backward, and to swing, thereby changing its posture. A more detailed description of the orienting ring support 100 can be found in US 5,174,502 entitled "A Support for Orienting Rings for Moving Nozzles" by Lippmeier et al., incorporated herein by reference.

Although the preferred embodiments of the present invention have been fully described for the purpose of explaining the principles of the invention, it should be understood that various modifications and changes can be made without departing from the scope of the invention as defined in the appended claims.

Claims (10)

1. A nozzle fail-safe actuation system (2) for an aircraft gas turbine axisymmetric directional exhaust nozzle (14), which has a directional ring ( 86), these hinges are arranged circumferentially around the center line (8) of the nozzle and define the exhaust flow path in the nozzle (14), the fail-safe actuation system (2) of the nozzle includes: a first directional actuation system (2A) having a first set of actuators (90A) operatively connected to the directional ring (86); Group actuators deliver power; a second directional actuation system (2B) having a second set of actuators (90B) operatively connected to the directional ring (86); The actuator transmits power; The actuators of the first group and the actuators of the second group are arranged alternately along the circumference of the nozzle (14). 2. The nozzle fail-safe actuating system (2) according to claim 1, characterized in that the nozzle fail-safe actuating system (2) is hydraulically driven. 3. The nozzle fail-safe actuation system (2) according to claim 2, characterized in that it also includes a single hydraulic power source (H), which forms a hydraulic power source with said first and second fail-safe control devices connected. 4. The nozzle failure protection actuation system (2) according to claim 2, characterized in that it also includes first and second hydraulic power sources (H), which are respectively connected to the first and second failure protection control Each of the devices communicates with a respective hydraulic power source. 5. The nozzle fail-safe actuating system (2) according to claim 4, characterized in that it also includes first and second fail-safe control devices, which can fail-safe the first and second groups of actuators correspondingly a set (90A) to allow expansion of the fail-safe set of actuators to any position and attitude corresponding to that set by the non-fail-safe other set of the first and second set of actuators (90A and 90B) various locations. 6. The nozzle fail-safe actuating system (2) according to claim 5, characterized in that there are only two groups of actuators, the first and second groups of actuators (90A1, 90A2, 90A3) ( 90B1, 90B2, 90B3) each have only 3 actuators. 7. The nozzle failure protection and expansion actuation system (2) according to claim 5, characterized in that there are only two groups of actuators, the first and second groups of actuators (90A1, 90A2) (90B1 , 90B2) each have only 2 actuators. 8. The nozzle fail-safe actuation system (2) according to claim 5, characterized in that said first and second failsafe controls each include a recirculation valve (26A, 26B) operably disposed between said operator up control (28) and a rod chamber (30); The first and second failsafe controls and the recirculation valve are operable to allow hydraulic fluid to flow over the failsafe actuator group when one of the actuator groups is failed Direct flow between cavity (28) and rod cavity (30). 9. The nozzle fail-safe actuation system (2) according to claim 8, characterized in that the first and second hydraulic power sources (H) are two hydraulic pumps (146, 146, 148), wherein each pump is operable to provide hydraulic power to only one of said set of actuators and the corresponding fail-safe control device. 10. The nozzle failure protection actuation system (2) according to claim 8, characterized in that said first and second hydraulic power sources (H) are two hydraulic pumps, at least one of which is Also used to drive the aircraft hydraulic pump (156) of the aircraft hydraulic system.

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