Abstract: A pressure regulation servo-valve comprising a body having a utilization port, a feed port, and a return port, a spool mounted as a sliding fit in the body, the spool co-operating with the body to define a pilot chamber connected to the utilization port. The spool and the body together further define a priming chamber connected to the feed port via a second constriction and connected to the nozzle via a third constriction, and in which there exists a priming pressure acting on the spool in the first direction.

Abstract: A pressure regulation servo-valve comprising a body having a utilization port, a feed port, and a return port, a spool mounted as a sliding fit in the body, the spool co-operating with the body to define a pilot chamber connected to the utilization port. The spool and the body together further define a priming chamber connected to the feed port via a second constriction and connected to the nozzle via a third constriction, and in which there exists a priming pressure acting on the spool in the first direction.

Abstract: An aircraft having wheels with hydraulically-actuating friction brakes and independent drives for driving the wheels in rotation and enabling the aircraft to move in stages of independent drive when engines of the aircraft are inactive. A main hydraulic circuit with a pressure source powers the brakes when the pressure source is active; with an alternative braking circuit for enabling the brake system at least when the engines of the aircraft are stopped. The alternative braking circuit includes an accumulator that is used for parking braking and is kept under pressure by the pressure source of the main circuit when the pressure source is active. An auxiliary hydraulic circuit pressurized by an auxiliary pump and power system enables the independent drives to be actuated. The auxiliary hydraulic circuit is connected to the alternative braking circuit to maintain an operating pressure in the accumulator of the alternative braking circuit.

Abstract: An independent drive device for an aircraft, the drive device comprising a motor member, a drive mechanism for driving an aircraft wheel, which is adapted to co-operate with the wheel to drive it for rotation, and a coupling mechanism interposed between the motor member and the drive mechanism to selectively couple the wheel to the motor member. The coupling mechanism comprises two coupling members of complementary shape, comprising a first coupling member that rotates with the drive and a second coupling member that rotates with the motor member. The independent drive device includes measurement device for generating information representative of a relative speed of rotation of the second coupling member and the first coupling member. The drive device is associated with a motor controller that causes the motor to rotate so as to cancel the relative speed of rotation between the coupling members prior to coupling them together.

Abstract: The invention provides a method of taxiing an aircraft having at least one nose undercarriage at the front of the aircraft and main undercarriages, each undercarriage having wheels, the method comprising the steps of: fitting at least one of the wheels carried by the nose undercarriage with a main taxiing motor member, and fitting at least one of the wheels carried by the main undercarriages with an auxiliary taxiing motor member; and in response to a taxiing order, powering the main taxiing motor member to cause the aircraft to taxi, and in particular if the driving force developed by the main taxiing motor member on the aircraft is insufficient, powering the auxiliary taxiing motor member, as required.

Abstract: The invention relates to an aircraft having wheels fitted with hydraulically-actuating friction brake means and also hydraulically-actuated independent drive means for driving the wheels in rotation and enabling the aircraft to move in stages of independent drive in which the engines of the aircraft are inactive, wherein the aircraft is fitted simultaneously with a main hydraulic circuit including a pressure source that powers the brake means when said pressure source is active; with an alternative braking circuit for enabling brake means to be actuated at least when the engines of the aircraft are stopped, the alternative braking circuit including an accumulator that is normally used for parking braking and that is kept under pressure by the pressure source of the main circuit when said pressure source is active; and with an auxiliary hydraulic circuit pressurized by auxiliary pump means activated by an auxiliary power unit of the aircraft to enable the independent drive means to be actuated; the auxiliary h

Abstract: The invention relates to an independent drive device for an aircraft, the drive device comprising a motor member, drive means for driving an aircraft wheel in rotation, which means are adapted to co-operate with said wheel to drive it in rotation, and coupling means interposed between the motor member and the drive means to selectively couple the wheel to the motor member, the coupling means comprising two coupling members of complementary shape, comprising a first coupling member constrained to rotate with the drive means and a second coupling member constrained to rotate with the motor member. The independent drive device includes measurement means for generating information representative of a relative speed of rotation of the second coupling member relative to the first coupling member, the device being associated with motor control means adapted to cause the motor to rotate so as to cancel the relative speed of rotation between the coupling members prior to coupling them together.

Abstract: The invention provides a method of taxiing an aircraft having at least one nose undercarriage at the front of the aircraft and main undercarriages, each undercarriage having wheels, the method comprising the steps of: fitting at least one of the wheels carried by the nose undercarriage with a main taxiing motor member, and fitting at least one of the wheels carried by the main undercarriages with an auxiliary taxiing motor member; and in response to a taxiing order, powering the main taxiing motor member to cause the aircraft to taxi, and in particular if the driving force developed by the main taxiing motor member on the aircraft is insufficient, powering the auxiliary taxiing motor member, as required.