FR3054619A1 - INTEGRATED DISTRIBUTOR STABILIZER SERVO CONTROL FOR FLIGHT CONTROLS OF AN AIRCRAFT - Google Patents

Abstract

The present invention relates to a servocontrol (1) for the flight controls (10) of an aircraft (50). Said servo (1) comprises a power cylinder (2) provided with a body (21) and a rod (22), at least one distributor (3) provided with a jacket (32) and a drawer (31), modifying the fluid supply of said power cylinder (2), a control means (4) controlling displacements of said rod (22) by moving said slide (31) relative to said jacket (32) and servo means (5) in position of said drawer (31) with power cylinder (2). Said liner (32) is also movable relative to said drawer (31) and said body (21 '). Said servocontrol (1) comprises at least one displacement means (6) for said liner (32) in order to modify the fluid supply of said power cylinder (2) and thus to drive displacements of said rod (22) relative to said body (21) independently of the position of said control means (4).

Description

® FRENCH REPUBLIC

NATIONAL INSTITUTE OF INDUSTRIAL PROPERTY © Publication number: 3,054,619 (to be used only for reproduction orders)

©) National registration number: 16 01147

COURBEVOIE © Int Cl ⁸ : F15 B 13/044 (2017.01), F 15 B 13/00, B 64 C 13/40

A1 PATENT APPLICATION

©) Date of filing: 07.26.16. © Applicant (s): AIRBUS HELICOPTERS — RR. (© Priority: @ Inventor (s): MARGER THIBAUT, GROLL ARNAUD and COIC CLEMENT. (43) Date of public availability of the request: 02.02.18 Bulletin 18/05. ©) List of documents cited in the report preliminary research: Refer to end of present booklet (© References to other national documents ® Holder (s): AIRBUS HELICOPTERS. related: ©) Extension request (s): (© Agent (s): GPI & ASSOCIES.

FR 3 054 619 - A1

SERVO CONTROL WITH INTEGRATED STABILIZATION IN THE DISTRIBUTOR FOR FLIGHT CONTROLS OF AN AIRCRAFT.

The present invention relates to a servo control (1) intended for flight controls (10) of an aircraft (50).

Said servo control (1) comprises a power cylinder (2) provided with a body (21) and a rod (22), at least one distributor (3) provided with a jacket (32) and with a drawer (31), modifying the supply of fluid to said power cylinder (2), a control means (4) controlling displacements of said rod (22) by moving said drawer (31) relative to said jacket (32) and servo means (5) in position of said slide (31) with power cylinder (2). Said jacket (32) is also movable relative to said drawer (31) and to said body (21 '). Said servo control (1) comprises at least one displacement means (6) of said jacket (32) in order to modify the supply of fluid to said power cylinder (2) and thus to control displacements of said rod (22) relative to said body (21) independently of the position of said control means (4).

Stabilization servo integrated in the distributor for aircraft flight controls

The present invention is in the field of flight controls for aircraft and in particular flight controls for rotary wing aircraft.

The present invention relates to an integrated stabilization servo for a flight control of an aircraft as well as to a flight control comprising such a servo and to an aircraft equipped with one or more such flight controls.

A flight control of an aircraft makes it possible to pick up a piloting order generated by the pilot of the aircraft and to transmit it to one or more flight components, such as an aerodynamic control surface or else blades of a rotor by example, in order to modify the behavior of the aircraft in space.

A flight control is traditionally carried out mechanically, by means of a control member, such as a handle, a lever, a spreader or the like, connected to one or more flight members by means of mechanical wheelhouses with base of connecting rods, rods and / or cables. Today, a flight control system incorporates, at least on medium to large aircraft, a pilot effort amplification system arranged between the control unit and each flight unit.

In addition, latest generation aircraft sometimes use electrical flight controls, the mechanical linkages being replaced by electrical connections which transmit the position of the control unit to one or more computers. These computers then control one or more amplification systems in order to generate the appropriate displacements of the flight components.

The flight controls of an aircraft, whether mechanical or electrical, can be piloted by an automatic pilot in order to automatically ensure the movements of the flight components and, consequently, the piloting of the aircraft.

However, the flight controls applied in particular to a rotary wing aircraft must be particularly effective in order to ensure the flight safety of the aircraft.

In fact, unlike an airplane which generally comprises several control surfaces on the same piloting axis, an aircraft with rotary wing does not have redundant piloting of the flight components. The main rotor of the aircraft controls the pitch and roll axes by means of the variations in the longitudinal and lateral cyclic steps and the collective pitch of the blades of the main rotor, while the tail rotor ensures the control around the yaw axis.

In addition, an aircraft has a certain natural stability, which allows the control system of the control surfaces to be absent during reconfiguration after a failure. Conversely, a rotary wing aircraft is unstable in nature, which requires permanent control of the flight components in order to avoid, or at least limit, the risks of flight destabilization.

Consequently, the autopilot associated with the flight controls of a rotary wing aircraft must allow, on the one hand, a function for stabilizing the flight of the aircraft, by partially intervening in the movements of the flight components in addition to the actions of the pilot, and on the other hand a piloting function proper, intervening in place of the pilot to control the movements of the flight components.

To this end, a mechanical flight control for a rotary wing aircraft associated with an automatic pilot comprises in known manner:

a control member, for example a cyclic step handle, a collective step lever or else a spreader, intended to receive a piloting order from a pilot of the aircraft in the form of an action by this pilot aimed to move the control member,

a means of mechanical transfer of this piloting order of a pilot, generally a mechanical wheelhouse,

one or more amplification systems, generally a servo-control, linked to a flight component of the aircraft and by mechanical transfer in order to actuate the flight component,

a first cylinder, usually called "series cylinder", integrated by means of mechanical transfer, and capable of modifying the piloting order of the pilot in a manner completely transparent to the pilot, and

-a second cylinder, usually called a "trim cylinder" linked to the control member in parallel by mechanical transfer and capable of replacing the pilot's piloting order with an automatic pilot command.

The autopilot comprises one or more computers and determines control orders transmitted according to their effects and their functions to the serial cylinder and / or to the trim cylinder in order to lighten the pilot's workload.

The trim cylinder constitutes a force refocusing means arranged parallel to the mechanical transfer means and acts on the control member via a flexible connection, such as a spring box for example. Consequently, the actions of the trim cylinder are perceived for the pilot. In this way, a displacement generated by this trim cylinder modifies the position of the control member and acts on the transfer means according to the control commands of the autopilot in order to pilot the aircraft automatically.

The series cylinder is integrated by means of mechanical transfer, generally formed by a mechanical linkage and arranged between the control member and each amplification system. In this way, the displacements generated by this series actuator act on the displacement of the linkage downstream of the control member and, consequently, without acting on the position of this control member. As a result, the actions of the serial cylinder are completely transparent to the pilot, who does not feel the influence of the serial cylinder in the control unit. The series actuator acts on the transfer means according to the control commands of the autopilot in order to act on both static and dynamic stability and the comfort of piloting the aircraft.

The trim cylinder is preferably a slow-acting cylinder which avoids brutal and dangerous behavior of the aircraft. The trim cylinder has full control over the flight parameters of the aircraft.

The series actuator is a fast acting actuator in order to counter the unfavorable oscillations of the aircraft encountered in flight. Its authority must be limited and in particular lower than that of the trim cylinder in order not to destabilize the aircraft in flight, but also to allow the pilot enough time to react in the event of difficulty. The series cylinder is often an electric cylinder to allow these quick actions.

By its function, a series cylinder can be arranged inside or outside the cockpit of the rotary wing aircraft according to its architecture. An outdoor installation implies various and changing conditions of use, the series cylinder being notably subjected to difficult climatic conditions, such as high humidity, an extremely dirty or aggressive environment, such as sand or frost, as well as extreme temperatures. with large amplitudes, for example between -40 degrees Celsius (-40 ° C) to + 80 ° C.

Consequently, the resistance to these difficult climatic conditions requires, among other things, the installation of special sealing means which can increase the cost and the mass of this series actuator. In addition, and despite the installation of these sealing means, the frequency of maintenance or replacement of this series actuator can be increased depending on these difficult climatic conditions. As a result, the cost of maintaining this series cylinder is also increased.

The series cylinder must provide sufficient power to move the mechanical linkage of the flight control which incorporates various resistances such as friction forces and the inertia of the components to be moved. The use of an electric series actuator then involves a significant consumption of electric current. In this way, the electrical harnesses electrically supplying these series jacks are dimensioned accordingly and have stiffnesses which can be significant, adding additional efforts to those of this mechanical wheelhouse.

In addition, the integration of this series cylinder can be difficult on the mechanical wheelhouse of the flight control because of its size. Similarly, the mass of each cylinder can be relatively large, for example of the order of 800 grams (800g). This mass can also make balancing flight controls difficult.

Finally, the clearances present in the mechanical wheelhouse can degrade the precision and efficiency of the series actuator and, as a result, the precision of the stabilization of the aircraft.

In addition, the amplification system of a flight component of a rotary wing aircraft is generally a servo control. Such a servo-control comprises in known manner an actuator, such as a jack, at least one distributor supplying the actuator with fluid, a control means acting on each distributor in order to control the movements of the actuator and, consequently, to act on a flight member, and a servo means in position of the actuator and the distributor.

The cylinder can be single-body or double-body depending, for example, on the force to be applied to move the flight member. A double body cylinder has two bodies which are integral with one another and hydraulically segregated from one another. Each body has two chambers located on either side of a piston secured to a rod. A servo drive with a single body cylinder has a single distributor supplying the cylinder body. A servo drive with a double-body cylinder has two distributors supplying the chambers of each cylinder body respectively and independently.

The actuator therefore comprises at least one body and a rod movable relative to the (x) body. The rod is generally movable in translation parallel to a first axis of the rod. The rod of the jack is for example linked to the structure of the aircraft, preferably by a ball joint, while the body of the jack is movable relative to this structure of the aircraft and is linked to the flight member. . The reverse is also possible, the body then being linked to the structure of the aircraft, preferably by a ball joint, and the rod being movable relative to this structure and linked to the flight component.

In both cases, each distributor can be linked to the structure of the aircraft by a ball joint. Preferably, each distributor is integral with the body of the power actuator of the servo-control in order to eliminate the relative movements of each distributor vis-à-vis the body of the power actuator and, consequently, to limit the risks of failure.

Each dispenser is provided with a folder and a drawer, the drawer being movable relative to the folder. It should be noted that the drawer is generally movable in translation relative to the jacket, this translation being carried out parallel to a second axis of the drawer. However, rotary distributors are also used on some aircraft flight controls. The drawer is then movable in rotation relative to the liner, this rotation being carried out around the second axis of the drawer.

The control means is connected to a control member of the aircraft by means of transfer means. This control means acts on each distributor and controls the movement of the drawer relative to the jacket of this distributor.

Such a servo control can be used for both mechanical and electrical flight control. Indeed, for a mechanical flight control, the transfer means is generally a mechanical wheelhouse and the control means is for example a connecting rod of this mechanical wheelhouse linked to the drawer of each distributor. This connecting rod thus transmits the movement of the mechanical wheelhouse in order to move the drawer of each distributor.

For an electric flight control, the transfer means comprises for example electrical connections and at least one computer, the control means being constituted by an actuator, such as an electric actuator, controlled by a computer and linked to the drawer of each distributor so cause this drawer to move.

This displacement of the slide causes the supply of one of the chambers of each body of the jack and, consequently, a displacement of the rod of the jack with respect to the body (s).

The slaving position control means with the power cylinder provides information on the relative position of the rod relative to the cylinder body (s) to each distributor. In this way, when the displacement of the rod relative to the body (s) corresponds to the control order, the supply of the actuator by the distributor is stopped and, consequently, the displacement of the rod is also stopped. This movement of the cylinder rod is therefore controlled in position relative to the control order which caused the initial movement of the drawer of each distributor. The servo means is preferably mechanical, without impacting the control unit, this feedback being transparent to the pilot of the aircraft.

The servo means is notably linked to the transfer means when each distributor is linked to the structure of the aircraft. When each distributor is integral with the body of the power cylinder, this control means is formed directly by the recess-type connection between each distributor and the body of the power cylinder, each distributor then accompanying the movements of the body of the power cylinder by relative to the rod of the power cylinder.

The displacements of the drawer of each dispenser are generally very small. These movements authorize the supply of fluid to the actuator cylinder. On the other hand, the displacements of the rod of the jack which ensure the displacements of the flight member can be greater.

Furthermore, document US Pat. No. 4959581 is known which describes a servo control comprising a control stage provided with electrical means and a hydraulic means as well as a power stage. The electrical means is a piezoelectric element arranged inside the hydraulic means and deforms under the application of an electric voltage in order to modify the hydraulic supply of the power stage by the hydraulic means.

In addition, the technological background includes document US 4101114 which describes an easily removable hydraulic distributor in order to modify in particular the elastic characteristics of a servo means and document US 8066090 which describes a hydraulic device for controlling an automatic gearbox for hybrid motorization.

The present invention aims to overcome the limitations mentioned above related to the installation of a series actuator on a mechanical wheelhouse of a flight control of an aircraft by eliminating the use of such an actuator series while enjoying the function provided by this series cylinder.

In this context, the present invention relates to a servo-control with integrated stabilization having a means of complementary control of the displacement of the rod of the actuator cylinder. The present invention also relates to a flight control for an aircraft comprising such a servo-control with integrated stabilization and not comprising a series actuator on its means for transferring a piloting order.

The invention also relates to an aircraft provided with at least one such flight control. The invention further relates to a method of moving the rod of the actuator cylinder.

According to the invention, an integrated stabilization servo comprises:

-a power cylinder provided with at least one body and a rod, the rod being movable relative to the body (s),

at least one distributor supplying the power cylinder with fluid, each distributor being provided with a jacket and a drawer, each drawer of a distributor being movable relative to the jacket of this distributor in order to modify the supply power cylinder fluid,

a control means controlling movements of the rod relative to the body (s) by moving the drawer of each dispenser relative to the jacket of this dispenser, and

-a means of servo-control in the drawer position with the power cylinder.

This integrated stabilization servo is intended for flight controls of aircraft and is more particularly adapted to the needs of rotary wing aircraft.

This integrated stabilization servo control according to the invention is remarkable in that the jacket of each distributor is movable relative to the drawer of this distributor and to the body of the power cylinder in order to modify the fluid supply of the power cylinder and the servo control. comprises at least one displacement means linked to each liner in order to move the liner of a dispenser relative to the drawer of this dispenser and to the body of the power cylinder and, consequently, to control displacements of the rod relative to ( x) body regardless of the position of the control means.

Each displacement means may be integral with the structure of the aircraft, by means of a connection of the undercarriage type or else by a ball joint connection. Preferably, each displacement means is integral with the body of the power cylinder. , by means of a built-in type connection, and thus allows the jacket of a distributor to move relative to the body of the power cylinder.

This integrated stabilization servo is intended for mechanical flight controls, the control means being for example a part of a mechanical wheelhouse, such as a connecting rod, linked to the drawer of each distributor. This integrated stabilization servo can also be used with electric flight controls, the control means being constituted by one or more actuators linked respectively to the drawer of each distributor as well as to one or more computers of the electric flight control.

This servo-control with integrated stabilization thus allows a first displacement of the rod of the power jack carried out following a displacement of the drawer of each distributor relative to the jacket of this distributor controlled by the control means. The drawer is moved relative to the distributor jacket as well as to the body (s) of the power cylinder.

This first movement follows an action of piloting an aircraft pilot or else an automatic pilot of the aircraft on a flight control control member comprising the integrated stabilization servo control according to the invention . This first movement thus generates a movement of the flight component associated with this flight command in order, for example, to maneuver the aircraft in flight.

Advantageously, this servo-control with integrated stabilization also allows a second displacement of the rod of the power cylinder which is produced following a displacement of the jacket of each distributor with respect to the drawer of this distributor as well as with respect to the cylinder body (s) regardless of the position of the control means.

This second displacement follows an action by an automatic pilot of the aircraft directly on each distributor of the integrated stabilization servo control by means of each displacement means linked to the jacket of each distributor. This second movement then generates a movement of the flight member in order to stabilize the flight of the aircraft independently of the piloting actions of a pilot of the aircraft on the flight control control member comprising the servo control to integrated stabilization.

The power cylinder can be a single-body cylinder with a single body, the integrated stabilization servo control having a single valve. The integrated stabilization servo then has only one displacement means in order to move the jacket of this distributor.

The power cylinder can also be a double-body cylinder provided with two bodies, the integrated stabilization servo control comprising two distributors.

In this case, the drawers of these two distributors are preferably mechanically secured to one another and the two shirts of the two distributors are also mechanically secured to one another. The integrated stabilization servo then has only one displacement means in order to simultaneously move the two liners. In this way, the two distributors open and close simultaneously and in the same way in order to avoid the appearance of antagonistic forces between the two bodies of the power cylinder.

However, although these drawers of the two distributors are mechanically secured to one another, the two shirts of the two distributors may not be mechanically linked to each other. The integrated stabilization servo then comprises two separate displacement means linked respectively to the jacket of a distributor and making it possible to move the shirts of the two distributors respectively and independently.

The two movement means can then be controlled in order to move the shirts of the two distributors simultaneously and in an identical manner.

However, it is possible to control the two displacement means in order to move the shirts of the two distributors with an offset. This shift in displacement of the two liners can make it possible, for example, to supply the two bodies of the power cylinder out of sync.

Furthermore, the use of two displacement means and two mechanically segregated shirts can also make it possible to facilitate the adjustment of the position of the “hydraulic neutral” of the assembly formed by the two distributors as well as the synchronization of the two distributors. This use of two separate displacement means and mechanically segregated shirts can also make it possible to compensate for a desynchronization of the distributors following in particular their wear.

In addition, the movement of each liner is subjected to only low resistance, each liner being neither linked to the flight control transfer means nor to the flight component. In addition, these movements of the shirt also have a small amplitude. Consequently, the displacement means advantageously has small dimensions and a reduced mass.

Each displacement means is for example an electric actuator, such as an electric actuator or else a compact piezoelectric actuator. Each displacement means can also be a hydro-electric servovalve.

For example, this electric actuator comprises a body with an internal diameter of the order of a few tens of millimeters, typically 50mm, has a stroke of the order of a few tenths of a millimeter, typically 0.2mm, and develops an effort of a few tens Newtonian, typically 50 Newton.

Furthermore, a dispenser may include in addition to the drawer and the folder, an outer folder. The folder is then arranged between the drawer and the outer folder, and can be designated "intermediate folder" or "intermediate drawer". This distributor advantageously makes it possible, in the event of the drawer seizing with respect to the jacket, to move the assembly formed by the drawer and the jacket with respect to the external jacket and to allow the operation of the distributor and, consequently, of the servo-control. . In normal operation of the dispenser, in the absence of seizure, the folder is movable with respect to the drawer and the outer folder and the drawer moves relative to the folder.

Consequently and for this type of distributor, the displacement means can be linked either to the jacket or to the external jacket, then causing the displacement of the jacket or of the external jacket respectively with respect to the drawer and the power cylinder. of the integrated stabilization servo control.

The present invention also relates to a flight control of an aircraft comprising a flight member of the aircraft, a servo-control with integrated stabilization as previously described and linked to this flight member, a control member and a means of transfer of a piloting order.

The transfer means is linked to the control member as well as to the integrated stabilization servo-control and makes it possible to transmit to the servo-control a piloting order supplied by a pilot of the aircraft via the control member. . The transfer means is more precisely linked to the servo control means and controls the first displacement of the rod of the power cylinder and, consequently, a displacement of the flight component.

Each means of displacement of the integrated stabilization servo control directly causes a displacement of the jacket of each distributor with respect to the drawer of this distributor as well as with respect to the body (s) of the power cylinder and then controls the second displacement of the rod of the power cylinder and, consequently, a displacement of the flight component independently of a piloting order supplied by the control component. This displacement means thus has a function identical to the series actuator traditionally used on the mechanical transfer means of a flight control in order to stabilize the behavior of the aircraft. Each means of movement is controlled by an automatic pilot of the aircraft.

Such an flight control of an aircraft comprising a servo-control with integrated stabilization therefore does not require the presence of a series actuator to ensure in particular the stabilization of the aircraft. On the other hand, this flight control may include a trim actuator so that an automatic pilot of the aircraft generates first displacements of the rod of the power actuator and, as a result of displacements of the flight component.

The use of each means of displacement of the integrated stabilization servo control in place of a serial cylinder of the flight control has several advantages.

First of all, the means of movement causing the movements of the jacket of each dispenser can easily be isolated and / or protected from the external environment and its aggressions, thereby increasing its service life and reducing the frequency of maintenance operations. and indeed their costs.

In addition, each means of movement provides less effort to perform its function, namely to move only the jacket of each distributor and no longer a part of the mechanical wheelhouse of the flight control, which allows on the one hand to reduce its dimensions and its mass and on the other hand to lower its consumption of electric current when this means of movement is an electric actuator.

Finally, this reduction in the efforts to be provided allows the use of displacement means having higher operating frequencies than a traditional series actuator, without significant increase in the dimensions and the mass of this displacement means. The increase in these operating frequencies advantageously leads to an improvement in the precision and the reactivity of the displacement stroke of the rod of the power cylinder and consequently an improvement in the stabilization and comfort of the flights of the aircraft.

The integrated stabilization servo allows for example to double the frequency traditionally used for a series actuator, which is of the order of 5 Hertz (5 Hz), the displacement means being able to have a frequency of the order of 10 Hz.

The present invention also relates to an aircraft comprising several flight controls, at least one flight control of which is provided with an integrated stabilization servo control, and an autopilot linked to each means of movement of each integrated stabilization servo control. The autopilot acts on each means of movement in order to stabilize the behavior of the aircraft by acting on the flight component of each flight control.

The present invention also relates to a method of moving the rod of the cylinder of a servo-control, the servo-control comprising:

a power cylinder provided with at least one body and a rod, the rod being movable in translation relative to the body (s),

at least one distributor supplying the power cylinder with fluid, each distributor being provided with a jacket and with a drawer, each drawer of a distributor being movable relative to the jacket of this distributor,

-a control means controlling movements of the rod of the power cylinder relative to the (x) body, and -a servo means in position of the drawer with the power cylinder.

During this process, the rod of the power cylinder is moved relative to the body (s):

-or by moving the drawer of each distributor relative to the shirt of this distributor through the control means,

-or by moving the jacket of each distributor with respect to the drawer of this distributor and to the power cylinder by means of a dedicated displacement means and independently of the position of the control means.

In this way, a first displacement of the rod of the power cylinder is carried out following a displacement of the drawer of each distributor with respect to the jacket of this distributor and to the body (s) of the power cylinder, this displacement of the drawer of each dispenser being controlled by a movement of the control means. This first movement follows an action of piloting an pilot of the aircraft or else of the automatic pilot of the aircraft and generates a displacement of the flight component in order for example to perform a maneuver of the aircraft in flight .

Likewise, a second displacement of the rod of the power cylinder is carried out following a displacement of the jacket of each distributor with respect to the drawer of this distributor and to the body (s) of the power cylinder regardless of the position of the control means. . Such displacement of the jacket of each distributor is controlled by a dedicated displacement means linked to the shirt of at least one distributor. This second displacement follows an action by the automatic pilot of the aircraft and generates a displacement of the flight component in order to stabilize the flight of the aircraft independently of the piloting actions of a pilot of the aircraft and of the flight maneuver of the aircraft.

The invention and its advantages will appear in more detail in the context of the description which follows with examples of embodiment given by way of illustration with reference to the appended figures which represent:

FIG. 1, a rotary wing aircraft comprising a flight control,

- Figure 2, a flight control with a servo control with integrated stabilization

FIGS. 3 and 4, two detailed views of the distributors and of a double-body power cylinder of a servo-control with integrated stabilization, and

- Figure 5, a dispenser comprising two shirts.

The elements present in several separate figures are assigned a single reference.

FIG. 1 shows an aircraft 50 comprising a main rotor 51 provided with main blades 55 and positioned above a fuselage 53 as well as an anti-torque device 52 in yaw, such as a rear rotor, provided with secondary blades 56 and positioned at the rear end of a tail boom 54. The aircraft 50 also comprises several flight controls in order to modify respectively the collective and cyclic pitch of the main blades 55 of the main rotor 51 as well as the collective pitch of the secondary blades 56 of the rotor anticouple 52. A single flight control 10 is shown in FIG. 1.

This flight control 10 comprises a control member 17, such as a cyclic step handle, a transfer means 18 constituted by a mechanical linkage, an integrated stabilization servo control 1 and a flight member 15. This flight control 10 thus allows to modify the longitudinal and lateral cyclic pitch of the main blades 55 of the main rotor 51 then constituting the flight member 15.

The aircraft 50 also includes a seat 20 for a pilot 59 in order to use the control member 17 as well as an automatic pilot 8 which can act directly on the integrated stabilization servo-control 1 of the flight control 10. The automatic pilot 8 can also act on a flight actuator trim cylinder 10 not shown in the figures.

FIGS. 2 to 4 represent several embodiments of a servo-control with integrated stabilization 1. In common, a servo-control with integrated stabilization 1 comprises a power cylinder 2, at least one distributor 3 supplying the power cylinder 2 with fluid, a control means 4, a servo means 5 in position and at least one displacement means 6.

The power cylinder 2 can be a single-body cylinder provided with a single body 21 as shown in FIG. 2, the integrated stabilization servo control 1 then comprising a single distributor 3 supplying fluid to the two chambers 24, 25 of the body 21 According to this figure 2, the body 21 is linked to the structure 57 of the aircraft 50 by a ball joint while the rod 22 is linked to the flight member 15 and movable relative to the body 21 and to the structure 57 of aircraft 50.

The power cylinder 2 can also be a double-body cylinder provided with two bodies 21, 21 ′ as shown in FIGS. 3 and 4. The integrated stabilization servo control 1 then comprises two distributors 3.3 ′, each distributor 3.3 'independently supplying fluid to the two chambers 24, 25, 24', 25 'of one of the two bodies 21, 21'. According to these Figures 3 and 4, the rod 22 is linked to the structure 57 of the aircraft 50 by a ball joint while the bodies 21, 21 ′ are linked to the flight member 15 and movable relative to the rod 22 and to the structure 57 of the aircraft 50.

In all cases, the rod 22 is movable in translation relative to the body (s) 21, 21 ′ along a first axis A1 of the rod 22. Each distributor 3.3 ′ comprises respectively a jacket 32, 32 ′ and a drawer 31.31 'movable in translation relative to the jacket 32.32' along a second axis A2 of the drawer 31.31 '. A displacement of each drawer 31.31 ’makes it possible to modify the supply of fluid to the power jack 2 and thus generate a displacement of the rod 22 relative to the body 21.21’.

The control means 4 moves the drawer 31.31 'of each distributor 3.3' respectively with respect to the jacket 32.32 'of each distributor 3.3' and the body (s) 21.21 'and thus controls, by modifying the supply of fluid to the power cylinder 2, displacements of the rod 22 relative to the body (s) 21, 21 ′ and, consequently, displacements of the flight member 15, in this case a variation of the cyclic pitch of the main blades 55 of the main rotor 51.

The flight control 10 shown in FIG. 2 is mechanical and the control means 4 is part of the transfer means 18 of this flight control 10. The control means 4 is linked to the control member 17 by a bar conjugation 19 of the transfer means 18 and thus transmits to the distributor 3 the piloting orders corresponding for example to the movements that the pilot 59 generates on the control member 17.

The servo-control means 5 in position is shown in FIG. 2, the flight control 10 being visible as a whole. This control means 5 in position makes it possible in a known manner to create a link between the position of the drawer 31 of the distributor 3 and the position of the rod 22 of the power cylinder 2 relative to the body (s) 21.21 ’. In this way, the servo-control means 5 in position makes it possible to stop the supply of fluid to the power cylinder 2 as soon as the movement of the rod 22 relative to the body 21 corresponds to the pilot's control order 59.

Furthermore, whatever the embodiment, the servo control 1 comprises at least one displacement means 6.6 ’linked to the sleeve 32.32’ of a 3.3 ’distributor. Each displacement means 6.6 'makes it possible to move at least one shirt 32.32' of a distributor 3.3 'relative to the drawer 31.31' of this distributor 3.3 'as well as with respect to (x) body 21,21 'of the power cylinder 2.

Consequently, such a displacement modifying the position of the jacket 32.32 ′ of a distributor 3 relative to the drawer 31.31 ′ and to the body (s) 21.21 ′ modifies the supply of fluid to the power cylinder 2 and therefore makes it possible to control displacements of the rod 22 relative to the body (s) 21, 21 ′ and, consequently, displacements of the flight member 15. Advantageously, this displacement of the jacket 32.32 ′ with respect to the body (s) 21,21 'is controlled by the autopilot 8 and produced without moving the slide 31,31' relative to the body (s) 21,21 '.

This movement is therefore independent of the position of the control means 4 and completely transparent to the pilot 59 of the aircraft 50. This movement of the jacket 32.32 'relative to the body (s) 21.21' thus makes it possible to move the flight member 15 in order to stabilize the flight of the aircraft 50 and in particular improve the comfort of this flight.

Then, the servo means 5 in position being linked to each distributor 3.3 ′ and to the power cylinder 2 causes a displacement of each drawer 31.31 ′ and thus makes it possible to stop the supply of fluid to the power cylinder 2 as soon as the displacement of the rod 22 relative to the body (s) 21, 21 ′ corresponds to the order of control of the automatic pilot 8 having generated the displacement of each sleeve 32, 32 ′.

According to FIG. 2, the integrated stabilization servo control 1 comprises a single distributor 3 in order to supply the body 21 of the power cylinder 2 and, consequently, a single displacement means 6 allowing the jacket 32 to be displaced. The displacement means 6 is linked to the structure 57 of the aircraft 50 by a ball joint.

According to FIGS. 3 and 4, the integrated stabilization servo control 1 comprises two distributors 3.3 ′ in order to supply the two bodies 21.21 ′ of the power cylinder 2. The drawers 31.31 ′ of the two distributors 3.3 ′ are always mechanically attached to each other.

According to FIG. 3, the two sleeves 32, 32 ′ of the two distributors 3.3 ′ are also mechanically secured to one another, connected for example by a spacer 35. The integrated stabilization servo control 1 then has only one means displacement 6 in order to simultaneously and identically move the two liners 32, 32 ′. The displacement means 6 is integral with the body 21.21 ’of the power cylinder 2.

According to Figure 4, the two shirts 32.32 ’of the two distributors 3.3’ are not mechanically linked from one another. Consequently, the integrated stabilization servo 1 comprises two displacement means 6,6 'linked respectively to a sleeve 32,32', the two displacement means 6,6 'being controlled in order to move the two sleeves 32,32' respectively. . The two displacement means 6 are integral with the bodies 21, 21 ′ of the power cylinder 2.

The autopilot 8 can then control the two displacement means 6,6 'in order to move the jacket 32,32' of the two distributors 3,3 'simultaneously and in the same way or with an offset causing a desynchronized supply of the two bodies 31 , 31 'of the power cylinder 2 of the integrated stabilization servo control 1.

Furthermore, a dispenser 3 comprising a drawer 31, a jacket 32 and an external jacket 33 is shown in the figure

5. The jacket 32 is arranged between the drawer 31 and the external jacket 33 and is movable both with respect to the drawer 31 and with respect to the external jacket 33. According to this FIG. 5, the displacement means 6 is integral with the bodies 21 , 21 'and linked to the jacket 32. The displacement means 6 thus causes the displacement of this jacket 32 relative to the drawer 31 and to the external jacket 33 which modifies the supply of fluid to the power cylinder 2 and causes a second displacement of the rod 22 relative to the body 21 and, consequently, a displacement of the flight member 15, independently of the position of the control means 4.

However, a similar operation is possible by linking the displacement means 6 to the external jacket 33 of this distributor 3.

Naturally, the present invention is subject to numerous variations as to its implementation. Although several embodiments have been described, it is understood that it is not conceivable to identify exhaustively all the possible modes. It is of course conceivable to replace a means described by an equivalent means without departing from the scope of the present invention.

Claims (12)

1. Servo control (1) with integrated stabilization comprising: a power cylinder (2) provided with at least one body (21.21 ’) and a rod (22), said rod (22) being movable relative to said body (21.21’), at least one distributor (3) supplying said power cylinder (2) with fluid, each distributor (3) being provided with a jacket (32) and a drawer (31), each drawer (31) with a distributor (3) being movable relative to said jacket (32) of said distributor (3) in order to modify the supply of fluid to said power cylinder (2), a control means (4) controlling displacements of said rod (22) relative to (x) said body (s) (21,21 ') by moving said drawer (31) of each distributor (3) relative to said jacket (32) of said dispenser (3), and -a servo means (5) in position of said drawer (31) with said power cylinder (2), characterized in that said jacket (32) of a distributor (3) is movable relative to said drawer (31) said distributor (3) and said body (s) (21,21 ') of said power cylinder (2) in order to modify the fluid supply of said power cylinder (2) and said servo-control (1) comprises at least one displacement means (6,6 ') linked to said shirt (32) in order to move said shirt (32) relative to said drawer (31) and to said body (s) (21,21') and, consequently, to control displacements of said rod (22) relative to the said body (s) (21,21 ') independently of the position of said control means (4). 2. Servo control (1) according to claim 1, characterized in that said power cylinder (2) is a single body cylinder provided with a single body (21) and said servo control (1) comprises a single distributor (3) supplying fluid to said body (21). 3. Servo control (1) according to claim 1, characterized in that said power cylinder (2) is a double-body cylinder provided with two bodies (21,21 ') and said servo control (1) comprises two distributors (3, 3 '), each distributor (3.3') respectively supplying fluid to one of said two bodies (21,21 '). 4. Servo drive (1) according to claim 3, characterized in that said drawers (31,31 ') of said two distributors (3,3') are mechanically integral with one another and said two shirts (32,32 ') of said two distributors (3,3') are mechanically secured to one another, said servo control (1) comprising a single displacement means (6) in order to simultaneously move said two liners (32,32 '). 5. Servo drive (1) according to claim 3, characterized in that said drawers (31,31 ') of said two distributors (3,3') are mechanically integral with one another while said two shirts (32, 32 ') of said two distributors (3,3') are not mechanically linked to each other, said servo-control (1) comprising two displacement means (6,6 ') linked respectively to a jacket (32,32 '), said two movement means (6) being controlled in order to respectively move said two shirts (32,32'). 6. Servo control (1) according to any one of claims 1 to 5, characterized in that each displacement means (6,6 ’) is an electric actuator. 7. Flight control (10) of an aircraft (50) comprising a flight component (15), an integrated stabilization servo (1) linked to said flight component (15), a control component (17) and a transfer means (18) linked to said control member (17) and to said integrated stabilization servo (1) in order to transmit a control command to said servo control (1), characterized in that said integrated stabilization servo (1) is according to any one of claims 1 to 6. 8. Flight control (10) according to claim 7, characterized in that each displacement means (6) makes it possible to stabilize the behavior of said aircraft (50) by acting on said flight member (15) independently of an order of control provided by said control member (17). 9. Flight control (10) according to any one of claims 7 to 8, characterized in that each displacement means (6) is piloted by an automatic pilot (8) of said aircraft (50). 10. Aircraft (50) comprising several flight controls (10), characterized in that at least one flight control (10) is according to any one of claims 7 to 8. 11. Aircraft (50) according to claim 10, characterized in that said aircraft (50) comprises an automatic pilot (8) linked to each displacement means (6,6 ') of a servo-control with integrated stabilization (1) d '' at least one flight control (10) and piloting each movement means (6,6 ') in order to stabilize the behavior of said aircraft (50) by acting on said flight component (15) of each flight control (10) . 12. Method for moving the rod (22) of a power cylinder (2) of a servo control (1), said servo control (1) comprising: -a power cylinder (2) provided with at least one body (21.21 ’) and a rod (22) movable relative to the said body (s) (21.21’), at least one distributor (3) supplying said power cylinder (2) with fluid, each distributor (3) being provided with a jacket (32) and a drawer (31), each drawer (31) with a distributor (3) being movable relative to said jacket (32) of said distributor (3) in order to modify the supply of fluid to said power cylinder (2), a control means (4) controlling displacements of said rod (22) relative to the said body (s) (21.21 ’), and -a servo means (5) in position of said drawer (31) with power cylinder (2), characterized in that a displacement of said rod (22) of said power cylinder (2) relative to (x) said body (s) (21.21 ') is performed, - Either by moving said drawer (31) of each distributor (3) relative to said jacket (32) of said distributor (3) and to said body (s) (21,21 ') by means of said means control (4), - or by moving said jacket (32) of each distributor (3) relative to said drawer (31) of said distributor (3) and to said body (s) (21,21 ') independently of the position of said means of control (4) via said dedicated displacement means (6,6 '). 1/2 A2 γττ 21 6 21 -> TZÏW. 31 33