Abstract: A landing gear of an aircraft having an upper portion intended to be joined to a structure of the aircraft and a lower portion provided with a first and second axle, the first axle being provided with a braked wheel and the second axle being provided with a motorised wheel, includes a first actuator that moves one of the axles between remote and close positions with respect to the upper portion while the other axle is kept stationary with respect to the upper portion. In one of the remote and close positions, and the wheels on the axles are simultaneously in contact with a running surface while, in the other position, each wheel on the second axle is at a distance from said running surface.

Abstract: An encapsulated shock absorber of an aircraft undercarriage includes a sliding rod slidably mounted in a leg strut of the undercarriage and an inner cylinder extending inside the strut. The inner cylinder is fastened to the strut via a top end, and the rod slides around the inner cylinder. The inner cylinder is terminated inside the sliding rod by a diaphragm that defines an oil chamber in the shock absorber and inside the sliding rod. A mixed oil/gas chamber is located in the inner cylinder, and an expansion chamber extends between the sliding rod and the inner cylinder. A hole being made in the inner cylinder in register with the expansion chamber is connected by a pipe to a pressure sensor situated outside the strut. The pipe extends inside the inner cylinder from the hole to the top end of the inner cylinder.

Abstract: The invention provides a method of moving an aircraft undercarriage comprising a leg (1) that is movable between a deployed position and a retracted position in which the leg is held stationary by means of a strut (2) held in an aligned position by a stabilizer member (4), the method including using a drive actuator (10) for raising the undercarriage from the deployed position to the retracted position. According to the invention, the actuator is coupled firstly to the leg and secondly to the stabilizer member in such a manner that on being activated the actuator begins by causing the stabilizer member to unlock and then moves the undercarriage leg towards the retracted position.

Abstract: The invention relates to a method of driving an aircraft undercarriage between a deployed position and a retracted position, the undercarriage comprising a leg (2) that is hinged to a structure of the aircraft in order to be movable between those two positions and being stabilized in the deployed position by means of a brace member (10) comprising two limbs (11, 12) that are hinged to each other, one of which is coupled to the leg and the other of which is coupled to the structure of the aircraft, the limbs being brought into an aligned position when the leg is in the deployed position. According to the invention, a rotary actuator (20) is arranged on the aircraft, which actuator comprises first and second cranks (22, 24) that are mounted to turn freely about a common axis of rotation but that have a relative angular position that can be controlled, and that are arranged to stabilize the limbs of the brace member in the substantially aligned position.

Abstract: An aircraft undercarriage having a sliding rod slidably mounted in a strut-leg, and a scissors linkage (4) having one branch (4a) hinged to the strut-leg or to a turning element of a control for steering the sliding rod mounted to turn in the strut-leg, and one branch (4b) hinged to the sliding rod, the branches being hinged to each other by a pivot pin (12), the undercarriage being fitted with a shimmy-attenuator device (10a, 10b) placed on the pivot pin of the shimmy-attenuator, the attenuator device including threshold resilient return means generating a force returning the branches towards a rest position, and at least damping means generating a damping force when the branches move axially along the pivot pin. The attenuator device comprises two modules (10a, 10b) placed on either side of the scissors linkage in order to co-operate with the pivot pin, each of the modules performing at least one of the damping function and the threshold resilient return function.

Abstract: An aircraft undercarriage has an axle for carrying at least one wheel. The undercarriage further includes a magnetic measurement target and at least one magnetic movement sensor cooperating with the magnetic measurement target to measure bending of the axle. The magnetic measurement target has a body that extends inside the axle and includes a fastener end fastened to one end of the axle. The body also include a target surface that extends over an inside surface of the body. The magnetic movement sensor is positioned inside the axle to measure movement of the target surface.

Abstract: The invention relates to an aircraft undercarriage having a leg (2) pivotally mounted on a structure of the aircraft to pivot about a pivot axis (X1) between a deployed position and a retracted position, the undercarriage including a foldable brace (3a, 3b) comprising two hinged-together elements, one of which is hinged to the leg and the other of which is hinged to the structure of the aircraft, in such a manner that when the leg is in the deployed position, the two brace elements are locked together in a substantially aligned position, the undercarriage also being provided with a rotary drive actuator (10) having an outlet shaft acting on one of the elements of the foldable brace in order to cause the leg to pivot between its two positions.

Abstract: A magnetic measurement target is configured to be positioned inside a vehicle axle and to cooperate with at least two magnetic movement sensors to measure deformation of the axle. The magnetic measurement target includes a body with a fastener end for fastening to one end of the axle and a main portion. The main portion includes a slot formed in an axial direction to separate two longitudinal portions of the body. Each longitudinal portion of the body presents a target surface for which movement can be measured by a magnetic movement sensor.

Abstract: The invention relates to a method of driving an aircraft undercarriage between a deployed position and a retracted position, the undercarriage comprising a leg (2) that is hinged to a structure of the aircraft in order to be movable between those two positions and being stabilized in the deployed position by means of a brace member (10) comprising two limbs (11, 12) that are hinged to each other, one of which is coupled to the leg and the other of which is coupled to the structure of the aircraft, the limbs being brought into an aligned position when the leg is in the deployed position. According to the invention, a rotary actuator (20) is arranged on the aircraft, which actuator comprises first and second cranks (22, 24) that are mounted to turn freely about a common axis of rotation but that have a relative angular position that can be controlled, and that are arranged to stabilize the limbs of the brace member in the substantially aligned position.

Abstract: The invention provides a method of moving an aircraft undercarriage comprising a leg (1) that is movable between a deployed position and a retracted position in which the leg is held stationary by means of a strut (2) held in an aligned position by a stabilizer member (4), the method including using a drive actuator (10) for raising the undercarriage from the deployed position to the retracted position. According to the invention, the actuator is coupled firstly to the leg and secondly to the stabilizer member in such a manner that on being activated the actuator begins by causing the stabilizer member to unlock and then moves the undercarriage leg towards the retracted position.

Abstract: A magnetic measurement target is configured to be positioned inside a vehicle axle and to cooperate with at least two magnetic movement sensors to measure deformation of the axle. The magnetic measurement target includes a body with a fastener end for fastening to one end of the axle and a main portion. The main portion includes a slot formed in an axial direction to separate two longitudinal portions of the body. Each longitudinal portion of the body presents a target surface for which movement can be measured by a magnetic movement sensor.

Abstract: An aircraft undercarriage has an axle for carrying at least one wheel. The undercarriage further includes a magnetic measurement target and at least one magnetic movement sensor cooperating with the magnetic measurement target to measure bending of the axle. The magnetic measurement target has a body that extends inside the axle and includes a fastener end fastened to one end of the axle. The body also include a target surface that extends over an inside surface of the body. The magnetic movement sensor is positioned inside the axle to measure movement of the target surface.

Abstract: An aircraft undercarriage having a sliding rod slidably mounted in a strut-leg, and a scissors linkage (4) having one branch (4a) hinged to the strut-leg or to a turning element of a control for steering the sliding rod mounted to turn in the strut-leg, and one branch (4b) hinged to the sliding rod, the branches being hinged to each other by a pivot pin (12), the undercarriage being fitted with a shimmy-attenuator device (10a, 10b) placed on the pivot pin of the shimmy-attenuator, the attenuator device including threshold resilient return means generating a force returning the branches towards a rest position, and at least damping means generating a damping force when the branches move axially along the pivot pin. The attenuator device comprises two modules (10a, 10b) placed on either side of the scissors linkage in order to co-operate with the pivot pin, each of the modules performing at least one of the damping function and the threshold resilient return function.

Abstract: The invention relates to an aircraft undercarriage having a leg (2) pivotally mounted on a structure of the aircraft to pivot about a pivot axis (X1) between a deployed position and a retracted position, the undercarriage including a foldable brace (3a, 3b) comprising two hinged-together elements, one of which is hinged to the leg and the other of which is hinged to the structure of the aircraft, in such a manner that when the leg is in the deployed position, the two brace elements are locked together in a substantially aligned position, the undercarriage also being provided with a rotary drive actuator (10) having an outlet shaft acting on one of the elements of the foldable brace in order to cause the leg to pivot between its two positions.

Abstract: Aircraft landing gear having a leg (12) for hinging to a structure of the aircraft so as to be movable between a deployed position and a retracted position, a main brace (15), a secondary brace (20), and a double-acting type unlocking actuator (30) having a first end coupled to the secondary brace and controllable for causing its links to move out of alignment against the action of the resilient member during retraction or deployment of the landing gear. The landing gear includes couplers (31, 33) for coupling to a second end of the unlocking actuator, which couplers ensure movement of said second end relative to the leg so that, for a given action, the unlocking actuator tends to break the alignment of the links when the landing gear is in one of its positions and tends to confirm said alignment when the landing gear is in its other position.

Abstract: The invention relates to aircraft landing gear comprising: a leg (12) for hinging to a structure of the aircraft so as to be movable between a deployed position and a retracted position, a main brace (15), a secondary brace (20), and an unlocking actuator (30) having a first end coupled to the secondary brace and controllable for causing its links to move out of alignment against the action of the resilient member during retraction or deployment of the landing gear. According to the invention, the unlocking actuator is of the double-acting type and the landing gear includes coupling means (31, 33) for coupling to a second end of the unlocking actuator, which means ensure movement of said second end relative to the leg so that, for a given action, the unlocking actuator tends to break the alignment of the links when the landing gear is in one of its positions and tends to confirm said alignment when the landing gear is in its other position.

Abstract: A dry friction clutch plate is of the kind having a metallic support plate with ring-shaped friction pads arranged on either side of it. A ring-shaped compression element is arranged between the friction pads, this ring-shaped element being of a cellular material. The cellular material is a deformable material having open and/or closed cavities or pores such as to cause the thickness of the ring-shaped compression element to be reduced when the clutch plate is subjected to compressive stresses, and to cause it to revert to its original thickness on the removal of the compressive stresses.