The invention relates to piloting devices used by the pilot in an aircraft cockpit. It relates in particular to an active stick including an integrated force feedback to assist the pilot.

TECHNOLOGICAL BACKGROUND

A piloting device in an aircraft cockpit comprises, in the usual way, a piloting stick with in particular a control lever rotatably mounted about a so-called roll axis and a so-called pitch axis, these two axes being orthogonal to each other. the other. Most often, devices of the "broomstick" type are encountered.

Depending on the position of the lever along these two axes, the piloting device transmits movement commands to the piloting members of the aircraft.

On the most recent models of aircraft, the control of the movements of the aircraft is electronic and the piloting device integrated into the cockpit can be of the "side stick" type. The position of the lever along the two roll and pitch axes is measured by sensors and translated into movement commands. The lever is not directly mechanically linked to the moving parts of the aircraft. There is no direct mechanical feedback on the lever for the pilot.

However, it is desirable for flight safety for the pilot to perceive a mechanical feedback at the level of the lever. Cockpit signaling systems may not be sufficient to cause the pilot to react quickly enough to unforeseen events during flight. The piloting sensations are much better if the mini-control stick incorporates a force feedback, also called "haptic feedback".

It has been proposed as such to equip the sidestick with passive mechanical systems, such as spring systems, or active electromechanical systems.

Furthermore, it has been proposed in document FR 3 011 815 to use an active force feedback device with an electric motor. Typically, in this document, the aircraft flight control device comprises a control lever mounted on a plate and connected to a roll axis motor and a pitch axis motor via shafts. transmission. The two motors are controlled according to a law of effort, so as to generate a resistive force opposing the force exerted on the lever (force feedback) when a force threshold is exceeded by the pilot.

Such a device is effective in restoring the sensations of piloting and increasing flight safety. However, in the event of an electrical or mechanical failure in one of the motors or in the event of a failure in the motor control signal processing chain, the force feedback can be suppressed.

In the field of aeronautics, the requirements for the availability of piloting devices are high. It is therefore not acceptable for the pilot to suddenly switch to a control mode without force feedback, in the event of an engine failure or its processing chain.

In addition, state-of-the-art active force feedback systems often include a significant number of components, including roll and pitch motors, but also clutches, torque limiters, gears, and more. These systems can be expensive, bulky, and difficult to integrate into an aircraft cockpit.

SUMMARY OF THE INVENTION

In view of the above, there is a need for a control stick incorporating a mechanical emergency channel, to prevent the rotation of the lever from being free and the pilot from losing all force feedback, in the event of an electrical failure. affecting a force feedback motor.

The desired stick must not be able to switch, in the event of a failure affecting said engine, in a mode in which the pilot freely pivots the lever.

There is a secondary need for a joystick in which, in the event of a failure affecting said engine, the lever is not completely immobilized.

Preferably, the desired mechanical emergency channel provides a variable resistive force depending on the position of the lever relative to a neutral point, in the event of a failure affecting the force feedback motor.

We are also looking for a mini-handle with less mass, bulk and power consumption compared to the existing one.

As such, according to a first aspect, the invention relates to a force application device for a pilot stick of an aircraft, in which the pilot stick comprises a control lever connected to at least one motor comprising a drive shaft movable in rotation about an axis, the force application device comprising:

a first pawn, connected to the tree,

a casing, configured to be fixed relative to the aircraft,

a second pin, fixed to the housing,

an electromagnet, fixed relative to the housing,

an actuator movable relative to the housing, said actuator comprising a magnetic material,

means for tightening the first pin and the second me pin, comprising a first tooth and a second tooth, the first tooth and the second tooth being movable relative to the first pin and the second pin,

the force application device having an operating configuration, in which the electromagnet is active and the actuator is positioned between the first tooth and the second tooth such that the first tooth and the second tooth are separated by distance from the first pin and the second pin, and a locking configuration in which the electromagnet is inactive and the actuator is retracted, so that the first tooth and the second tooth are in contact with the first pin and the second pawn.

A first advantage of the invention is to provide a mechanical escape route to prevent the lever from being completely free in its pivoting movement. In the event of a failure affecting the motor, the electromagnet is no longer active and the force application device assumes a blocking configuration.

Resistant torque, opposing rotation of the first pin relative to the housing, is exerted on the first pin when the force application device is in the locked configuration. Indeed, the clamping means comprise teeth which clamp the first pin and the second pin, the second pin being integral in rotation with respect to the housing. The drive shaft is then braked in its rotational movement.

An advantage of the invention is that the mechanical emergency channel provided by the force application device is reversible, the force application device being able to adopt an operating configuration again when the electromagnet is at new asset.

A second advantage is to avoid a complete immobilization of the drive shaft associated with the motor, when an electrical failure affects the motor and when the electromagnet is no longer active. Indeed, the clamping means do not necessarily completely block a rotation of the first pin relative to the second pin.

Note that the force application device of the invention tends to return, when in the locking configuration, the pilot lever towards a fixed neutral point. The second pin being fixed with respect to the casing, the neutral point does not depend on the position of the first pin during the passage of the device to the blocking configuration.

Advantageously, the actuator of said force application device is movable according to a current supply of the electromagnet.

CLAIMS

1. Device for applying force for a pilot stick of an aircraft, in which the pilot stick comprises a control lever (1) connected to at least one motor (3a) comprising a drive shaft, the 'drive shaft being movable in rotation about an axis (A), the force application device comprising:

a first pin (30a), configured to be connected to the drive shaft, a casing (4), configured to be fixed relative to the aircraft, a second pin (40a), fixed to the casing,

an electromagnet (5a), fixed relative to the housing,

an actuator (6a) movable relative to the housing, said actuator (6a) comprising a magnetic material, so that said actuator (6a) is movable according to a current supply of the electromagnet (5a),

clamping means (7a) of the first pin and of the second pin, comprising a first tooth (71) and a second tooth (74), the first tooth and the second tooth being movable relative to the first pin and the second pin, the force application device having an operating configuration, in which the electromagnet (5a) is active and the actuator (6a) is positioned between the first tooth (71) and the second tooth (74) so that the first tooth and the second tooth are separated at a distance from the first pin and the second pin, and a locking configuration in which the electromagnet (5a) is inactive and the actuator (6a) is retracted, so that the first tooth (71) and the second tooth (74) are in contact with the first pin and the second pin.

2. A force applying device according to claim 1, wherein the actuator comprises a magnetic piston (61).

3. A force application device according to claim 2, wherein a direction of movement of the magnetic piston (61) belongs to a plane orthogonal to a longitudinal direction of the first pin and orthogonal to a longitudinal direction of the second pin.

4. Force application device according to one of claims 1 to 3, wherein the clamping means comprise a first jaw (70) and a second jaw (73), and wherein one end (72) of the first jaw and one end (75) of the second jaw are linked to the housing (4) by return means (78).

5. A force application device according to one of claims 1 to 4, further comprising an angular displacement sensor (11a) configured to acquire a measurement of angular displacement of the drive shaft.

6. A force application device according to one of claims 1 to 5, further comprising a damping part (14a) extending on a contact surface (31) between the first pin (30a) and the second pawn (40a).

7. Cockpit of an aircraft comprising a control lever

(1), comprising at least one motor (3a) which has a drive shaft, the drive shaft being movable in rotation about an axis (A), the handle further comprising a device for applying d 'force according to one of claims 1 to 6 by motor.