Abstract: A braking system for a railway vehicle having bogies which have fixed axles and independent wheels, the braking being of the disk-brake type. Each brake includes multiple disks comprising rotary disks (7) secured to the wheel (2) to be braked and fixed disks (8) secured to the axle (1) carrying the wheel to be braked, braking being obtained by pressing the fixed disks against the rotary disks, the system also including a cooling circuit enabling the heat energy generated by braking to be dissipated, cooling being obtained by a forced flow of fluid through the circuit.

Abstract: A switching component for a metal-clad station provides the equivalent of three three-phase section switches respectively disposed on two outlets powering sets of three-phase busbars and allowing grounding of the section switches upstream therefrom. The section-switching and grounding are performed by first contact parts engagable with second contact parts electrically connected together and to ground, and third contact parts. The second contact parts and the third contact parts are carried by a common shaft rotatable about the shaft axis.

Abstract: A gas blast circuit breaker comprises a cylindrical metal or insulative enclosure filled with pressurized insulative gas, a fixed arc contact and a mobile assembly coupled to an operating member comprising a gas blast cylinder associated with a gas blast nozzle and cooperating with a piston, and a mobile arc contact carried by a tubular member inside the gas blast cylinder. The inside wall of the tubular member comprises a bottleneck whose cross-section is less than the inside cross-section of the tubular member and coaxial therewith. The minimum cross-section of the bottleneck has a diameter less than or equal to the diameter of the inside cross-section of the mobile arc contact and equal to at least 0.75 times the diameter of the inside cross-section of the mobile arc contact. The operation of the circuit breaker is improved by increasing the gas pressure near the mobile arc contact by virtue of a particularly simple and low-cost arrangement.

Abstract: A system for sensing the position of a rotating steel shaft (1), the system comprising an eddy current sensor and a track (3) fixed to the shaft and going past the sensor, the track being constituted by a strip (4) of electrical insulation material having areas of non-ferromagnetic material with good electrical conductivity regularly distributed around the shaft, wherein the face of the strip (4) provided with the areas of non-ferromagnetic material is glued to the shaft (1). This very simple system serves to obtain a signal of larger amplitude.

Abstract: A linkage for articulated vehicles, in particular rail vehicles, the linkage serving to provide connection between an intercommunication tunnel supported by a bogie and the ends of adjacent cars supported by the intercommunication tunnel, the cars and the intercommunication tunnel being coupled together near the bottoms thereof, the linkage being characterized in that the end of each car (2, 3) is connected to the tunnel (1) near the top thereof by means of a connection rod (10, 11), with the connection rods being interconnected by link elements, the assembly constituted by the connection rods and the link elements constituting a deformable parallelogram.

Abstract: The present invention consists in a connection arrangement between at least one pair of conductors that pass through respective walls (6). Each wall (6) is made of insulating material and the two walls are connected together via a peripheral sealing gasket received in a groove (7') and delimiting an empty space between the walls which is filled with dry air. The connection made in this way is small in size and is particularly easy to implement.

Abstract: A rail vehicle bogey includes a transverse chassis (1) carrying the body of the vehicle. Indepently motorized wheels are connected to the chassis via resilient hinges (6) including a pivotable hinge arm which supports a traction motor (20) for independently motorizing each bogey wheel. Each arm supports the traction motor by a cradle defined by two branches of the hinge arm forming a fork and interconnected at one end by a spacer. One fork of each arm constitutes a transmission housing between the motor (20) and a wheel (4), whose axis is offset with respect to the axis of the corresponding independently motorized wheel (4).

Abstract: A method of making at least one low electrical resistance connection between a metal and a high T.sub.c superconducting ceramic part, said part being made from a ceramic powder which is placed in a mold, compressed, and sintered, wherein at least one volume of silver or gold powder corresponding to the shape of said connection and situated at the desired location is placed inside said mold in juxtaposition with said ceramic powder but without being mixed therewith, after which the compression and the sintering are performed under an atmosphere containing oxygen and at a temperature that is lower than the melting temperature of silver or gold.

Abstract: A medium-voltage circuit-breaker comprises a sealed enclosure filled with a dielectric gas and containing a semi-fixed first contact electrically connected to a first terminal and a mobile second contact electrically connected to a second terminal and mechanically coupled to an operating member. The semi-fixed contact is associated with a piston moving in a first cylinder constituting a first volume and provided at one end with a nozzle in which the mobile contact can be inserted when the circuit-breaker is in the engaged (on) position. The piston is acted on by a spring urging it in the direction in which the first volume decreases. The circuit-breaker comprises a system for causing the gas to circulate automatically between the first volume and a second volume when the current to be interrupted reaches a predetermined threshold value. The semi-fixed contact is a tube communicating with a third volume consisting of the remainder of the enclosure.

Abstract: A method is provided for asynchronous motor control by closed-loop variation of magnetic induction flux as a function of a desired value in which the closed-loop variation includes flux measurement on the basis of measurement of motor voltage and current and determination of a measured flux value obtained using said measurements and characteristic parameters of said motor in accordance with the motor operating equations, the method including the steps of obtaining the measured flux for an arbitrarily fixed value of at least one of said parameters wich may significantly differ from the actual value thereof and of then correcting the desired value in order to compensate for this possible difference.

Abstract: A circuit breaker comprising, for each pole, at least one interrupting chamber having fixed contacts and moving equipment including a moving contacts, and in parallel with each interrupting chamber series circuit comprising a varistor and a switch, said switch being open when the circuit breaker is disengaged and being closed when the circuit breaker is engaged. The switch comprises a moving contact driven by the moving equipment when the circuit breaker is performing an engagement operation, with the moving contact being constrained to follow the movement of the moving equipment when the circuit breaker performs a disengagement operation, but with a certain delay.

Abstract: A method and device are provided for estimating the magnetic induction flux of an asynchronous electric motor, notably for enabling said motor to be controlled by magnetic induction flux regulation, the method consisting of measuring the motor voltage and current, calculating a flux, defining a measured flux, using the operating equations for said motor and employing said measured values and predetermined values for characteristic parameters of said motor, one of which at least, being fixed arbitrarily, may differ considerably from the actual value thereof, and on the basis of said measured flux, calculating a flux defined as the estimated flux and which can be identified with the actual flux through the use of an expression deduced from said motor operating equations as a function of said measured flux, and from characteristic parameters of said motor other than said parameter having a arbitrarily fixed value which may differ considerably from said actual value, and if necessary from said voltage or current

Abstract: A turbine stage comprising a set of fixed vanes (1) fixed to the stator (3) of the turbine and supporting a diaphragm, followed by a set of moving vanes (8) mounted on a disk (9) which is fixed to the rotor (6) of the turbine, the periphery of the set of moving vanes (8) having seals (10) constituted by a plurality of chambers (11). The disk (9) includes suction orifices (16) opening out into the space between the diaphragm (4) and the disk (9) and disposed in the vicinty of the peripheral portion of the disk (9). The suction orifices (15) are connected by ducts (17) passing through at least some of the moving vanes (8) to outlet orifices (18) which open out in the tips of the vanes (8) downstream from the seals (10) within a chamber (11) thereof. The disturbed flow at the roots of the fixed vanes (2) and the leakage flow between the diaphragm (4) and the rotor (6) are sucked into the orifices (16), thereby improving efficiency.

Abstract: A superconductor protected against partial transition includes superconductor strands around at least one non-superconductor central strand or at least one non-superconductor central core electrically insulated from the superconductor strands. At least at both ends of the superconductor, the central strand or said central core is electrically connected to the superconductor strand. The central strand or the central core comprises at least one non-superconductor metal filament whose resistivity at 4.2.degree. K. is less than 10.sup.-9 .OMEGA..m embedded in a metal alloy matrix whose resistivity at that temperature is greater than 10.sup.-8 .OMEGA..m.

Abstract: An SF.sub.6 circuit breaker having a varistor incorporated in line with its interrupting chamber in which insertion of the varistor on opening and closing is performed by coaxial translation of two electrodes outside and around the main contacts.

Abstract: A high tension or medium tension circuit breaker having abutting arcing contacts. The circuit breaker includes a gastight insulating case filled with a gas having good dielectric properties. The case contains a stationary arcing contact; a moving arcing contact driven by a drive rod actuated by a mechanism outside the case. A blast chamber is defined by a piston integral with the moving arcing contact, slidably received in a fixed cylinder terminating in a blast nozzle, the cylinder and a ring. The circuit breaker further includes a lost motion mechanism to enable the drive rod to move over a given length in the circuit breaker opening direction without driving the moving arcing contact away from the fixed arcing contact.

Abstract: A rotor for a motor having magnets, the rotor comprising a rotary shaft and at least one pair of magnetic poles with magnets disposed therebetween having azimuth magnetization, the rotor being characterized in that the poles and the magnets are fixed to each other and to the rotor by a section member (30) of constant thickness having a section with as many lobes (31, 32, 33, 34) as there are poles in the motor, said lobes being interconnected in pairs by curved portions, (41, 42, 43, 44) which are substantially circular arcs of diameter close to that of the shaft (1) of the motor. The invention is applicable to a synchronous motor having magnets.

Abstract: A dielectric gas arc-blasting high tension circuit-breaker of the type including secondary arcing contacts enables pressure upon secondary arcing to be developed inside a secondary volume defined by two concentric tubes and a pair of axially spaced pistons carried by respective tubes to facilitate circuit-breaker opening. All of the electrical contacts of the circuit-breaker are disposed outside of the secondary volume.

Abstract: A gas filled medium tension circuit breaker includes an insulating case with a fixed first arcing contact connected to a first circuit breaker terminal. The circuit breaker includes moving equipment formed of a slidable first tube axially displaceable by a drive rod connected to one end of the slidable first tube. The slidable first tube is connected by contacts to a second circuit breaker terminal. The first tube and a fixed second tube define a blast volume. The second tube is extended by a blast nozzle. A second arcing contact is defined by a third tube which slides inside a small diameter portion of the slidable first tube, with that small diameter portion defining with the second tube the blast volume. A larger diameter second portion of the slidable first tube carries the blast nozzle. The two portions of the slidable first tube interconnect radially by a substantially annular portion having through holes and a shoulder.

Abstract: A medium tension circuit-breaker has a gastight insulating case filled with a gas having good dielectric properties. A semi-moving arcing contact is electrically connected to a first terminal and a moving contact is mechanically connected to a drive mechanism and electrically connected to a second terminal. The semi-moving arcing contact is connected to a piston movable in a blast volume delimited in particular by the inside wall of an insulating cylinder which is inside the case and by a first face of a blast nozzle. The piston receives thrust from a spring in which energy is stored when the circuit-breaker is in the engaged position. The circuit-breaker includes a thermal expansion volume delimited in particular by the inside wall of the cylinder, by a second face of the nozzle, and by a transverse partition through which the moving contact slides.