Abstract: The invention relates to a flapping restrainer device for the blades of a rotorcraft main rotor, and a rotor head comprising the same. The lower restrainers comprise a reciprocal star-shaped plate (32), having as many radial branches (33) as blades, and each one of the branches being engaged into a radial opening (6) of the hub (3). Outside the latter, the star-shaped plate (32) cooperates with supporting runners (47) integral with the blades. The upper restrainers comprise, for each blade, a stop which is retractable by the effect of the centrifugal force and which is composed of a lever (52), pivoting on a pivot (53) carried by the hub (3), and a first arm (55) of which constitutes a stop finger directed towards an upper supporting component (60) integral with the blade, while a second arm (56) carries a governor weight (57) and a nose (58) for support against a shoulder (59) integral with the hub (3).

Abstract: A carriage moves on a track and carries, through a flexible linkage, a chassis to which is fixed a payload including an optical element. A linear actuator controls the linkage so as to correct imperfections in displacement of the payload. A piezo-electric accelerometer delivers a filtered signal to control the linear actuator so as to eliminate the effect on the payload of vibration of the carriage. There are two independent control loops, one for controlling the carriage and the other for controlling the chassis. The device is applicable to controlling the mobile part of an optical delay line or of a telescope in a stellar interferometer.

Abstract: The resilient return strut is of the elastic-hydraulic type with incorporated linear damping by throttling a high-viscosity fluid, and comprises a damper (1) mounted between two return springs (2, 3) in elastomer-based sleeves (17, 18), undergoing a shearing action and sealing the chambers (34, 35) set off within the body of the damper (12) by a transverse wall (10) which marks off a permanent throttling passage around a central brace (23). Limiting valves equipped with spring-leaves (45) sealing the holes (40) bored in the wall (10) increase the throttling section. A compressed-air system (52), mounted in a spring (2), compensates for thermal expansion of the fluid. The device is used with helicopter rotors.

Abstract: The invention relates to a control device for monocyclic pitch in a fixed reference system and multicyclic pitch in a rotating reference system, for the blades (7) of a rotor craft.In addition to conventional swashplates (27, 38), one (38) of which rotates (39) on the other (27) held in rotation by a nonrotating compass (28), but which slides axially (4) and oscillates (25) about the rotor mast (1), through the action of pilot control (30), it comprises multicyclic jacks (45) in a number equal to the blades (7), and each of which is implanted in the rotating plate (38) and directly drives a pitch control rod (44) of a corresponding blade (7). Each multicyclic jack (45) is a dual-action, hydraulic linear jack controlled by a servovalve (49) also implanted on the rotating plate (38).

Abstract: Method and system for determining the longitudinal position of the gravity center of an aircraft having an adjustable stabilizer. At a flight point for which the aircraft is in equilibrium with its elevator in aerodynamic prolongation of the adjustable stabilizer, the gravity center position is calculated from the position (X.sub.F) of the focus (F) of the aircraft (1), the measurement of the deflection (iH) of the adjustable stabilizer, a first function K(M, N1) of the engine speed (N1) of the engines of the aircraft and the Mach number (M). The first function is representative of the deflection value (iHRef) of the adjustable stabilizer. In the case where the gravity center would be at the focus (F) of the aircraft, a second function H(Cz, M) of the lift coefficient (Cz) of the aircraft and of the Mach number (M) is used. The second function is representative of the stabilizer deflection variation for a variation of 1 percent of the gravity center position.

Abstract: The invention relates to a milling cutter which comprises a body (1) having two indentations (4,5) presenting each a housing (4',5') the body of which makes with the longitudinal axis of the body an helix angle which is not equal to zero. In each housing a cutting insert (6,7) is removably fixed which comprises a corner portion emerging on the frontal face (9) of the body and a main or major cutting edge extending beyond along the external lateral rim of the indentation. The shape of this insert and its position on the cutter are such that the radial cutting angle of the cutter varies in decreasing towards the frontal end of the body, and that the clearance angle of the cutter is constant.

Abstract: The present invention relates to a process for making an assembly of electrically conductive patterns (9, 16) on an electrically insulating surface (20) of complex shape.According to the invention:said assembly of patterns (16) is formed on a face of a plastically deformable flat support (10);said flat support (10) is applied, by being deformed, against said surface (20) of complex shape; andsaid deformed flat support is connected to said surface (20) of complex shape.The invention finds an advantageous application in the production of reflectors for antennas.

Abstract: Contact link for flight controls of aerodynes, especially helicopters. The link comprises a rod (2) mounted axially slideably over a limited stroke under tension and under compression in a body (1). A leaf spring (35) subjected to compressive buckling prestress is accommodated in a recess (27) of the rod (2) between two supports (36, 37) pushed against stops of the rod (2) and stops of the body (1). Under any axial tensile or compressive force higher than the prestress of the leaf spring (35), one of the supports (36, 37) is brought nearer to the other, so that the leaf spring (35) works by buckling, and its central part increases its deflection to an extent amplified in relation to the axial stroke of the rod in the body and shifts radially a movable contact member (55) actuating an electrical contactor (45) fastened in the recess (27) of the rod (2). The contact link is used for equipping flight controls for cutting in or cutting out an automatic pilot.

Abstract: The invention relates to a process for the electrosynthesis of carboxylic acids of general formula R-COOH in which R is an organic radical by the electrochemical reduction, in the presence of carbon dioxide, of organic compounds corresponding to the general formula R--Y in which R is the above-mentioned organic radical and Y is a hetero atom-containing radical, the hetero atom of the radical Y, chosen from the group consisting of oxygen, nitrogen, sulphur andphosphorus, being directly linked to a carbon atom of the radical R by a single covalent linkage. When the hetero atom is nitrogen or phosphorus, the radical Y is an ammonium or phosphonium radical respectively.The anode, which is consumed during the electrosynthesis, is made of a metal chosen from the group consisting of reducing metals and their alloys, preferably made of magnesium, aluminium or zinc.This process without catalyst is very simple to perform and enables a cell with a single compartment to be employed.

Abstract: In this machine, rows of rods (R.sub.1.sup.2, R.sub.3.sup.2, R.sub.4.sup.3, R.sub.2.sup.3) representing the woof threads are circulated in passages A, B, C defined between filaments (86) forming concentric open loops having adjustable diameters. In the openings of the loops are needles (90) movable between neutral or open positions for deviating the rods from a passage into an adjacent passage while depositing warp threads in circular layers between the rods. The rods are then replaced by woof threads by a lacing device.

Abstract: A composite material blade is provided having a twin longeron and twin box structure with laminated honeycomb sandwich coverings, including a front leading edge longeron of a C shaped section, a central longeron with two sole pieces at the ends of a transverse web with honeycomb filling sandwiched between lateral sheets, and laminated coverings made from honeycomb panels sandwiched between external and internal sheets formed by stacking layers of fiber fabric, so as to define two boxes filled with very light foam cores, the sole pieces being integrated in the coverings which are joined at the level of the trailing edge by a rider in the form of a foam wedge.

Abstract: This invention relates to an electro-optical pickup of the type incorporating a charge coupled device. The invention has a sequencer that controls the successive acquisition by the photosensitive zone of a plurality n of images. The sequencer transfers into the intermediate memory zone, after formation of each of the images, a part of this image constituted by a number of lines m less than or at the most equal to the ratio M/n between the number M of lines of the intermediate memory zone and the number n of the images. The sequencer accumulates the partial images in the intermediate memory zone. The sequencer controls, via the readout register, the complete transfer of the partial images from the intermediate memory zone into the outside memory means, as well as the distribution of the partial images in the outside memory means.

Abstract: This invention relates to a cockpit comprising a seat with armrest, as well as a mechanical control member of the control stick type adapted to be actuated by one hand and mounted at a fixed location in said cockpit at least substantially in forward extension of an armrest of said seat, the position of said seat being adjustable with respect to said mechanical control member. According to the invention, at least a part of said armrest is articulated about a transverse pin connected to said seat, in order to be able to occupy a plurality of fixed positions of different inclinations about said pin, converging towards said mechanical control member and adjustable thanks to control means. The invention is more particularly applicable to the piloting of aircraft.

Abstract: Flight control system for aircraft of the type provided with ailerons, elevators, upper surface spoilers, and upper surface air-brakes, a rudder and horizontal stabilizers with variable angle of incidence, said system comprising an electric control, in some cases without any mechanical emergency control for said upper surface spoilers and air-brakes.According to the invention:the ailerons and elevators are electrically controlled without any mechanical aid,the rudder is mechanically controlled, andthe horizontal stabilizers with variable angle of incidence are electrically controlled with mechanical aid.the electrical flight controls are optimized.

Abstract: This invention relates to a process for making electrically conductive lines on a non-developable surface of an insulating substrate, to a tool for carrying out the process and to a device obtained thereby. The process consists in uniformly coating the surface of a layer of an electrically conductive matter, which is in turn coated with a layer of a protective matter. The contour of the lines is then traced mechanically on the layers by means of a tool hollowing out grooves, then the layers are subjected to the action of a chemical agent capable of attacking the layer of conductive matter without attacking the protective layer, after which those parts of the electrically conductive layer outside the lines are separated from the substrate by peeling. The invention is applicable, for example, to the making of electrically conductive lines on antenna reflectors.

Abstract: A system is provided for braking a vehicle, more especially an aircraft travelling over the ground, comprising an anti-locking regulator preventing the braked wheels from locking and receiving the difference of signals delivered by a tachometric sensor coupled to a braked wheel and by a reference signal generator. Said anti-locking regulator further comprises digital calculating means capable of sequentially calculating the expression ##EQU1## in which K0, K1 . . . Kn are constants, t1, t2, . . . tn are time constants and p Laplace's variable.

Abstract: A method of fabricating complex frames, e.g. for engines and aircraft comprises forming the principal components of the frame from resin-bonded filamentary material and securing them together, each of the principal components being formed by a method which includes the step of winding the filamentary material about a former having longitudinal axis and impregnating the material with a hardenable resin. One or more of the components so made may form part of the former for one or more of the other components. The method of forming the individual components may further include the step of axially dividing the element which is made by winding filamentary material about a former and impregnating the material with hardenable resin.

Abstract: The present invention relates to a safety tool-holder for machine-tools, comprising:a quill in which is axially cut a through-opening, said quill being mounted in a body integral with the machine-tool;a rod placed in the axial opening of the quill, a first end of which rod comprises gripping means adapted to grip a tool head, whereas the second end comprises a threaded portion;axial elastic return movement means, resting, first against the quill, and second, against a nut screwed on the threaded portion of the rod and making it possible to hold the latter in working position;means for continuously controlling the rod in its working position, which means detect the variation of the elastic deformation of the nut under the action of the elastic return means.The invention finds an application in machine-tools, such as milling machines.

Abstract: A multi-layer refractory structure is provided capable of withstanding high temperatures of the order of 2000.degree. C. to 2500.degree. C. for hundreds of hours. This structure comprises at least two layers, the first of which, subjected directly to said high temperatures and formed by a simple or composite metal oxide or a zirconate, has a thickness between about 1 mm and 4 mm and a specific gravity between about 2.2 and 4.8 and the second layer of which, which serves as support for said first layer, is of the same nature as this latter and has a thickness between about 5 mm and 12 mm and a specific gravity between about 2.2 and 4.2.

Abstract: Apparatus for the polymerization and/or crosslinking of a resin used in the composition of a composite material part having a variable thickness by means of ionizing radiation.The apparatus comprises means for producing an electron beam, means for directing the electron beam onto a target, which is able to produce under the action of the electron beam X-radiation offering adequate doses for crosslinking the resin, as well as means for carrying out a relative movement between the ionizing radiation and the part, so that the latter is wholly or partly exposed to the action of said radiation. It makes it possible to polymerize a part by X or electron beams, as a function of the thickness requirements thereof.