Abstract: A process for producing a fluidtight seal between a body of a vitroceramic material and a metal element intended to be part of the construction of a gas laser and in particular a laser gyrometer includes interposing between the surfaces of the body of vitroceramic material and the metal element to be sealed a joining member of a metal capable of diffusing into the vitroceramic material, and subjecting the assembly thus formed to a thermo-compression operation so as to result in a superficial diffusion of the material of the joining member into the facing surfaces of the body of vitroceramic material and the metal element.

Abstract: A gyroscopic artificial horizon comprises a gyroscope suspended in a gimbal ount which has an inner frame and an outer frame pivoted, one within the other, about two orthogonal axes. It also comprises a device for sensing the spatial position of the axis of the gyroscope and for displaying this position in the form of an artificial horizon. To simplify the mechanical structure and to increase the reliability of the gyroscopic artificial horizon, the device for sensing and displaying the spatial position of the gyroscope axis comprises a luminous display screen rotationally coupled to the outer frame of the gimbal mount. It further comprise a sensor for sensing the angular position of the inner frame relative to the outer frame and a processor device adapted to display this angular position on the screen in the form of an artificial horizon.

Abstract: Device for visualizing failures for gyroscopic instruments comprising, inendently of the size of the indicator which incorporates it, an intuitive warning means accounting simultaneously for the supply of the liability and for the speed conformity of the gyroscope to the required values. It comprises two complementary display zones in the rolling dial (5 and 6) made up by means of elements of liquid crystals presenting an opaque appearance in the presence of a supply voltage and showing a color required in the absence of a supply voltage. One of the zones (5) is comprised of a single active element informing of the disappearance of the supply while the other zone (6) is comprised of a plurality of juxtaposed active elements, which are progressively switched and which give a synoptic perception of the speed reduction of the gyroscopic top of the instrument.

Abstract: The invention provides a display device with dissociable structure, making t possible for a user to observe a synthetic light image superimposed in his natural field of vision, said device being formed as two dissociable modules, namely: an image generating module having, inside a case, at least one part of the image generating members and a removable optical module including a support element to which is fixed a curved mixer type optical mount including, in a dihedral configuration, a flat semitransparent mirror and a curved semitransparent mirror.

Abstract: A method and device are provided for guiding an aerodyne on the runway, picularly during the taxiing phase preceding take off, the device including an inertial unit adapted for delivering signals representative of the North speed, of the East speed, of the azimuth and of the ground speed of the aerodyne. From these signals, a computer elaborates a parameter defining the axis of the runway, during an apprenticeship step during which the aerodyne, guided on site by the pilot, taxies along the axis of the runway, and stores this parameter at the end of the step. The computer then delivers to the means piloting the aerodyne a synthetic runway aberration signal between the axis of the runway thus stored and the position of the aerodyne delivered by the inertial unit.

Abstract: A lighting sensor is provided including a sleeve made from a translucent erial having a bottom intended to be exposed to the light whose illumination it is desired to measure, an optoelectronic component positioned inside the sleeve with its sensitive face disposed in line with said bottom and means for securing said component and said sleeve together.The invention overcomes in a simple way the problems due to the non linearity of the signal delivered by the optoelectronic component to the saturation of this component and to the narrowness of its aperture angle.

Abstract: A gamma correction method and device are provided for multichrome cathode y tubes, including, for each of the n-1 electron guns of the tube, a correction circuit adapted for raising the cathode modulation of this gun to a power .gamma.ref/.gamma..sub.i in which the term .gamma..sub.ref is the gamma exponent of the nth gun which is taken as reference and the term .gamma..sub.i is the gamma exponent of the gun considered. With this device the chromaticity of the colors displayed on the screen are conserved throughout the whole contrast dynamics of the tube.

Abstract: The cylinder may be an aircraft landing gear axle. The items may be pick-ups the sense axle deformation. A ring (30) for supporting the pick-ups is made of highly resilient material. It is initially of such a size that its cylinder-engaging surface overlaps the cylindrical surface it is to engage. The ring is then deformed by urging at least two points (34 to 37) around its circumference to increase the degree of overlap. While maintaining the deforming force on the ring, its cylinder-engaging surface (31) is machined so that there is no longer any overlap, and still maintaining the force, the ring is engaged with the cylinder. The force is then removed. The said points move resiliently away from the cylinder, but intermediate points are consequently resiliently urged into contact with the cylinder. The contact is smooth and progressive, thus avoiding the kind of stress concentrations that could reduce cylinder life by fatigue, etc.

Abstract: The device comprises central anchor means firmly anchored to a lug (3), e.g. the smooth middle portion of a rod (10) capable of being thermally fitted in a smooth round hole (7) through the lug (3) together with first and second independent fixing means (26, 26') disposed on either side of said central anchor means, e.g. two threaded end portions (27, 27') fitted with nuts (28, 28', 29, 29').

Abstract: An accelerometer is provided using at least one sensor with flat pendular structure formed by micro-machining a fine monocrystal wafer and comprising a flat mobile mass suspended from the rest of the structure by means of two thin parallel strips situated on each side of the mass. The mass comprises at least one mobile capacitor plate disposed between two fixed capacitor plates provided on the fixed part of the structure. The mobile plate is brought to a voltage V.sub.O, whereas the fixed plates are respectively brought to voltages V.sub.1 and V.sub.2 which are capable of generating an electrostatic return force on the mobile mass.

Abstract: The device comprises at least three non-colinear studs (A,B,C) interposed between each lug face (5) against which a sensor or sensor mounting part is pressed. Stud (A) may be closer to a beam (1) than the other studs (b) and (C), thereby maximizing the relative displacement of the sensor parts for a given shear force on the beam (1).

Abstract: An accelerometer sensor comprising a flat pendular structure having a fixed part and a flat test body suspended from the fixed part by two parallel blades flexible in the plane of said test body, so as to be able to move in translation along a sensitive axis. Said test body extends at least partially into the space between said two flexible blades.

Abstract: A device for detecting the angular position of the rotor of an electric rry machine with electronic switching, comprising more particularly a disk mounted coaxially on the shaft of said rotor and comprising a radial face on which permanent magnets are fixed of alternately reversed polarity producing a magnetic field, Hall effect proximity cells disposed in the vicinity of said radial face of the disk and carried by a structure mounted for rotation on the body of said rotary machine coaxially with said axis, and adapted for detecting the axial component of the magnetic field, means allowing said structure to be locked against rotation on said body.

Abstract: The invention concerns a process for the rapid detection of a wind gradie t.This process utilizes the relationship existing between the aerodynamic slope .gamma.a, the total slope .gamma..sub.T and the anemometric speed V, relation being able to be in the form ##EQU1## in which s is the Laplace operator, A is a value which is substantially constant or zero, in the case of a normal flight without disturbances, and which increases in the case of a wind gradient, wind forward becoming wind behind, the Vsel is an assigned value. This value A is mixed with a value representative of the capacity of the aircraft to overcome a wind gradient, so as to obtain a composite signal compared to a value of reference.The invention can be utilized at the moment of the phase of approach of an aircraft.

Abstract: This invention concerns an improved variometer which is used in aircraft which operates on a circuit that calculates the instantaneous speed hx.degree. of the aircraft and the potential vertical speed of the aircraft h.sub.T .degree.. A luminous display is also provided to display the values so calculated to alert the pilot of the aircraft.The instantaneous vertical speed hx.degree. is obtained by means of a circuit solving the equation: ##EQU1## in which j.sub.z.sbsb. is the component of the acceleration on the vertical axis of the aircraft, g is the acceleration of gravity, .phi. is the angle of roll of the airplane, s is the Laplace operator, .tau..sub.1 and .tau..sub.2 are constants of time and h.degree..sub.A is a signal of vertical speed.

Abstract: A variometer for an aerodyne. The variometer has at least one dial conventionally graduated to represent speed, a needle indicating on said graduation the instantaneous vertical speed. The variometer also has an indicator which is representative of the potential vertical speed, and can move around the dial so that the position of the indicator with respect to the needle indicates instantaneously the acceleration on the trajectory of the aircraft.

Abstract: A process and system for the rapid detection of a wind gradient or change r an aircraft. Such a system provides for, on the one hand, the rapid detection of important or significant wind gradients or changes which can occur during the final phase of approach preceding the landing of the aircraft and, on the other hand, to inform the pilot or the automatic flight control system of the existence of this wind gradient sufficiently early to permit necessary corrective action to be taken.

Abstract: A method for controlling the decelerated approach of an aerodyne on radioignment generally referred to as "glide," in particular for the purpose of reducing its fuel consumption and reducing the noise, mainly in the final stage of the approach, by approaching the glide at high speed, initiating the descent according to the glide angle, also at high speed then beginning a decelerated phase in order to reach a predetermined speed V sel+k, k being generally equal to 10 knots, on reaching a predetermined altitude, h.sub.F, and then passing progessively from the speed V sel+k to the speed V sel. From the time when the aerodyne reaches the axis of the glide path, a course is determined in two sections, as regards the variables of speed and altitude, for reaching the point situated at the altitude h.sub.

Abstract: A power jack, particularly adapted to equip the control system of an aeroe, including stress-responsive components, for example, a helical coil spring, in which indicator instruments record any locking between the relatively movable elements of the jack, such as a rotatable shaft and an encompassing sleeve to thereby disengage a disengaging element and allow the control functions to bypass the jack.