Abstract: The method of controlling aircraft braking during landing on a runway as soon as the running gear of the main landing gear has made runway contact and prior to the nose gear making contact, comprises: determining the value of the nose-up angle .DELTA. of the aircraft as soon as it makes runway contact with its main landing gear; providing a signal representative of the value of the nose-up angle; and controlling braking of the aircraft by any appropriate braking apparatus as a function of a magnitude representative of the signal to ensure acceptable variation of said nose-up angle.

Abstract: The braking control system includes a generator for generating a first electrical control signal, a controllable fluid source suitable for delivering the fluid at a predetermined pressure at an outlet from the source, a slide valve for connecting the outlet of the source to a brake actuator, a circuit for measuring the value of the pressure at the outlet from the source, a circuit being suitable for delivering a second signal having a value representative of the measured pressure, and a controller for controlling the source of fluid as a function of the first and second signals in such a manner that the fluid pressure at the outlet from the source has a value which is a function of the first signal as corrected by the second signal.

Abstract: The present invention relates to landing gear. The landing gear has a strut (2) having one end pivotally mounted about a first axis (4) suitable for connection to the structure (1) of an aircraft. A lower portion (6) for supporting running gear (10) is pivotally mounted relative to said strut (2) to pivot about a second axis. A collapsible side brace (20) has one end suitable for connection to a first point (27) of the aircraft structure (1) for pivoting about a third axis (29) and a fourth axis (30) providing rotation with two degrees of freedom about said third and fourth axes respectively. The third axis (29) passes through said first point (27) being situated on a line which is not colinear with the first axis but which intersects said first axis at a second point (40). A pivot pin (33) is rotatable about a fifth axis (35), the fifth axis not being colinear with said first (4), third (29) and fourth (30) axes and being situated on a line which passes through said second point (40).

Abstract: A shock absorber including a cylinder (501), a rod (502) slidably mounted in the cylinder, and a piston (506) fixed to the rod and slidable inside the cylinder. The piston divides the cylinder into two oil-filled chambers (508, 514) and there is a third chamber (518) in the rod and including air to act as a hydraulic spring. Shocks tend to move the piston along the rod away from its equilibrium position therein, and the hydraulic spring tends to return the piston to its equilibrium position. Damping is provided by variable aperture channels between the first chamber (508) and the other two chambers (514 and 518). The channels comprise orifices (509 and 510) in a cylindrical wall of the first chamber (508) which overlap orifices in a movable cylindrical valve plate (527). A control shaft (540) leading out along the axis of the shock absorber serves to rotate the valve plate and to move it in axial translation.

Abstract: The shock absorber is characterized by the fact that it comprises a rod (1) sliding in a cylinder (2) through a piston (3) to determine at least two variable-volume chambers (4,6), ports (40,41) for placing the two chambers in communication, one of the two chambers (4) comprising first elastic fluid (44) at a first given pressure, the other chamber (6) comprising second elastic fluid (10) at a second given pressure, controllable according to at least one parameter, corresponding to a force to be absorbed.

Abstract: A two-way transducer for transfering power between two hydraulic circuits, e.g. to ensure uninterrupted hydraulic power in all the hydraulic circuits of a twin engined aircraft, even when one engine has failed. A body (1) has an elongate cavity (4) housing two barrels (14, 15) of cylinders (26) with pistons (28) slidably mounted therein. A common drive shaft (17) enables each barrel to drive the other. A wedge (16) located between the barrels provides two oblique surfaces (18, 19) for the piston heads to slide over. Sealing means (38, 39, 43, 44) to prevent fluid leaking from one circuit to the other. In operation one barrel operates as a swashplate type of motor driving the other barrel which then acts as a pump.

Abstract: The present invention relates to shock absorber-actuators.The shock absorber-actuator is characterized essentially by the fact that it comprises at least one cylinder (101), a hollow rod (102) sliding in the cylinder (101), a gas chamber (153) delimited by a separating piston (141), and means (140, 156, 154) for positioning this piston between two stops (145, 147).The shock absorber-actuator finds a particularly advantageous application in aircraft and in particular helicopters.

Abstract: This invention relates to hydraulic pumps. The pump includes essentially a casing (1), a barrel (3) capable of rotating on a slide face (2), the barrel comprising a plurality of pistons (16, 17) sliding in a reciprocating manner in cylinders (9, 10) provided in the casing, the pump being characterized essentially by the fact that it comprises structures (59, 54, 50, 52, 53) for sequentially applying the pressure prevailing in the cylinder on a given portion between a bearing block (26) made in the casing (1) and the part of said barrel (3) cooperating with the bearing block (26). The pump finds a particularly advantageous application in the area of those which must rotate at very high speed, for example in aeronautics.

Abstract: The undercarriage comprises: a leg (1) pivotally mounted about a first pivot axis (14) which is fixed relative to a rigid structure of the aircraft; a main side-brace (30) comprising at least two articulated levers (31 and 32) having first ends pivotally connected to each other about a fourth pivot axis (33), having respective other ends pivotally mounted about a second pivot axis (37) which is fixed relative to the rigid structure, and pivotally mounted about a third pivot axis (36) which is fixed relative to the leg; and a drive (40 to 48) for causing the levers to pivot relative to each other. The first, second, third, and fourth pivot axes are parallel to each other.

Abstract: This invention relates to landing gears. The described landing gear is characterized essentially by the fact that it comprises a leg (3) at one end of which is fixed a wheel (14 ) for rolling around a pivoting pin (11), a shock absorber (15) of which one end (22) is connected to leg (3), a strut (24) whose end is connected to leg (3) and links (39, 37, 41) connecting the end of strut (24) to the pivoting pin (11) so as to cause the wheel to pivot when the landing gear is retracted. This landing gear finds an advantageous application as a fuselage landing gear of the tripod type.

Abstract: The landing gear for aircraft comprises at least two rocker beams respectively carrying wheels, the rocker beams being connected rigidly and respectively to two points of the rigid structure of the aircraft, each rocker beam being connected to two other rigid points of the aircraft structure by an assembly composed of a lever and a shock absorber mounted rotatably on each other, and a connecting rod of constant length connecting two levers and an actuating cylinder to rotate at least one of the two said levers. The landing gear finds a particularly advantageous application as a fuselage landing gear with tandem mounted wheels.

Abstract: The present invention relates to landing gears retractable between two positions.The landing gear includes essentially a lever (14 ) mounted rotatably around an axis (5), a rocker beam (7) mounted rotatably on the same axis (5), a strut (21) including two links (22,23) pivoting in relation to each other, the strut being connected to the lever, a shock absorber (18) fixed respectively on the lever (14) and the rocker beam (7), and an actuating cylinder (32) for applying a pivoting force to the lever (14). This landing gear finds a particularly advantageous application in aircraft of the commuter type.CROSS REFERENCE TO RELATED APPLICATIONThe present application relates to application Ser. No. 354,010 filed on Mar. 2, 1982, and entitled "FUSELAGE LANDING GEAR WITH TANDEM WHEELS" by inventors Andre Turiot and Michel Derrien, our reference 4126.

Abstract: An oleopneumatic suspension with variable throttle orifices, particularly for aircraft landing gear comprising a rod (1) enclosing a pneumatic spring (2) and being fixed with respect to a piston (4) sliding in a cylinder (3), two valves (6) and (7) with permanent throttle orifices, the valve (6), which is of greater cross-section, throttling in the compression phase and the valve (7), which is of lesser cross-section, throttling in the extension phase, the suspension comprising in addition a throttle device, the section of whose orifice varies in dependence on the position and the direction of displacement of the piston (4) in the cylinder (3) so that over a given distance around a predetermined equilibrium position the orifices ensuring throttling in the compression and extension phases are of cross-sections respectively greater than the corresponding orifices over the remainder of the distance covered by the piston (4) in the cylinder (3).

Abstract: The present invention relates to landing gears. The landing gear includes essentially two legs (1, 2) comprising respecitvely two arms (10, 28) and two rocker beams (3, 24), a bar (21) forming with the two arms (10, 28) a deformable parallelogram, a strut (37) consisting of two levers (23, 38) placed on a diagonal of the parallelogram, two locking links (50, 51) cooperating with the strut (37), these two rotatably mounted links being rotated by an actuator (70) and a spring (60). The landing gear finds its application in commuter aircraft fitted with tandem type landing gears.

Abstract: The invention concerns a landing gear. The landing gear is characterized essentially by the fact that it comprises at least one shock absorber (15), this shock absorber being mounted in the leg (1) and casing (2) assembly by means of two convex surfaces (22, 31) made on the cylinder (16) of the shock absorber (15) and cooperating with two concave surfaces (25, 32) integral respectively with the leg (1) and the casing (2). This landing gear finds an application as a nose gear of the rocker-beam type.

Abstract: Devices for detecting the displacement of an element relative to a referential. A first end of a recopying bar is connected with the element and the other end is capable of cooperating with a mechanism for determining the displacement of this second end relative to the referential. The device is particularly useful for determining the deformation on landing gears of aerodynes.

Abstract: A main undercarriage train for an aircraft which is retractable substantially laterally, the train comprising two undercarriages which comprise identical legs each having a plane of symmetry which passes through its pivot mounting axis which is inclined relative to the plane of symmetry of the aircraft.

Abstract: The invention relates to a device for testing vehicle wheel rims. The device comprises means of positioning and holding the rim, means for applying loads on the rim, and is characterized by the fact that the said means for applying loads on the rim comprise, on the one hand, a set of controllable jacks whose heads are able to cooperate with the rim, and on the other hand, a control member to actuate the jacks successively according to a predetermined cycle. The device is particularly useful for testing the rims of aircraft wheels.

Abstract: An automatic braking method and apparatus for a vehicle, having particular applicability to aircraft, wherein a program deceleration signal is generated according to a preselected deceleration. A signal which is a function of the actual speed of the vehicle is compared with the program signal, and a difference signal is produced. The difference signal controls the actuation of the braking system of the vehicle to result in braking thereof in accordance with the preselected deceleration.

Abstract: The present invention relates to a fuse for a wheel equipped with a pneumatic tire.The fuse is constituted in the form of a screw (1) whereof the head (7) is traversed by an evacuation duct (3) receiving a check valve (8) obturating this duct (3); the fuse being characterized by the fact that it comprises a retainer (17), a part of which is embedded in the head, and another part cooperates with the check valve to hold it.