Abstract: The circuit breaker has linear displacement moving contacts (3, 4) coupled to a fixed cylinder blast assembly (6) having two concentric pistons (7, 8). The first piston (7) is fixed to the moving contact equipment and is actuated by the circuit breaker control mechanism. The second piston (8) is free and is driven by electrodynamic energy from the current being interrupted. A spring (23) urges the second piston (8) towards the top (16) of the cylinder. Coupling means (30) which lock the second piston (8) when it reaches the top of the cylinder are released by the first piston (7) when it leaves the vicinity of the top (16) of the cylinder. It only requires small operating energy while enabling small intensity and large intensity currents to be interrupted by matching itself thereto.

Abstract: Apparatus for supplying gas under pressure and distributing it between a plurality, n, of outlets (15) comprises a piston (1) slidably mounted in a cylinder (2), with the piston (1) being fixed to a rod (6) which serves to position the piston in the cylinder, and with the cylinder including a base (3) provided with a gas inlet (16) and a side wall (5) having n openings, each of which is connected to a corresponding gas outlet; said piston, when in a base end postion, serving to block communication between the inlet and the outlets; the improvement wherein the openings in the side wall are constituted by grooves (13) which extend over a shorter length than the axial extent of the piston, and whose depth in the thickness of the wall increases with distance from said base, the furthest end of each groove from said base being connected to an associated gas outlet, and each groove constituting together with the piston a convergent-divergent nozzle.

Abstract: Insulation process by impregnation of electric leads using isocyanate and oxazolidone cycle resins in which a glass cloth and porous mica paper tape is wound around the leads, the tape is impregnated with a quaternary ammonium salt, catalyzing condensation of isocyanate and epoxy derivatives in isocyanurate and oxazolidone cycles and with a varnish comprising a liquid epoxy resin and an isocyanate derivative, then the impregnated tape undergoes a heat treatment for polymerization of the varnish.As quaternary ammonium salt, is used a benzyltrialkylammonium halide with alkyl chain containing at most 3 carbon atoms, the tape is first impregnated with benzyltrialkylammonium halide and liquid epoxy resin, it is dried at a temperature equal to 135.degree. C. at maximum and then it is impregnated with isocyanate derivative based varnish before undergoing the polymerizing heat treatment.

Abstract: A motor-driven pump assembly which can be used under water and includes at least an electric motor (1, 2, 3)surmounted by at least one pump (4, 5) connected to the motor drive shaft so as to rotate, wherein the motor is electrically energized by means of an electric connection module (8) fixed to the lower end of the motor (1) beyond the space taken up by the shaft, said module having a connector pin (9) connected to a cable (10) which runs along the assembly and is fixed thereto.

Abstract: The concentration of air in water is rapidly reduced by 80% in a separation enclosure (28) at reduced pressure by virtue of prior injection of microbubbles of air into the enclosure (26). Degassed water is useful for scaling cavitation effects in a hydraulic test tunnel.

Abstract: A superconductor manufacturing process provides electrical insulation and enhanced transverse electrical resistivity of multifilament superconductor strands based on Nb.sub.3 Sn. The process includes forming, during the early manufacturing steps in which the product is relatively short and of large cross section, resistive barriers around bundles of filaments in an oxide powder doped with conductive materials. In subsequent steps, an electrically insulative powder is used to insulate between a copper tube surrounding the bundles of filaments and an outer resistive ring or to insulate around multifilament strands.

Abstract: An automatic sheet metal cutting machine has a continuous supply of metal strips in adjustable lengths, at will. A reciprocating cutter cuts laminations from the metal strip and a receiver receives the laminations. The receiver includes a swiveling plate movable through an angle .alpha. at will about a pin perpendicular to the direction motion of the laminations. The receiver is lowered and moved downstream relative to the direction of motion of the laminations received thereby.

Abstract: The circuit breaker comprises: a stand (1) at ground potential; a first insulating column (2) supported by said stand and filled with a highly dielectric gas; a second insulating column (4) coaxially supported by said first insulating column, said second insulating column serving as a cut-out chamber and including moving contacts (6) connected to a first current terminal (8) and associated with moving contact drive means (3), and fixed contacts (10) connected to a second current terminal (12). Said second column supports a third insulating column (13) which is coaxial with said first and second columns. At least one magnetic circuit and secondary winding (14A-14D) of a current transformer are disposed around said third column in the neighborhood of its connection to said second column. The primary circuit of said current transformer is constituted by a conductor (11) connecting said fixed contacts to said second terminal.

Abstract: A device for applying imbalance to a rotor comprises a plurality of chambers disposed symmetrically around the rotor. Each has an opening and is adapted to contain a fluid. Each of a plurality of opening devices associated with the chambers is operable under remote control so as to open the opening of the associated chamber, so that the fluid contained in it may be evacuated from it. Each opening device comprises a pyrotechnic valve incorporating a piston rigidly attached to an assembly and movable from a first position in which the assembly closes the opening of the associated chamber to a second position in which the assembly opens the opening. Such movement is obtained in response to firing of the pyrotechnic valve. The opening device also includes a control circuit which incorporates a receiver responsive to a signal transmitted from a fixed source with no material transmission medium. This control circuit fires the pyrotechnic valve.

Abstract: The invention provides a compressed gas circuit breaker provided both with a blast device comprising a piston (12), a cylinder (3A) and a blast orifice (10B) for sending a jet of compressed gas to the zone where an electric arc forms when the arc contacts (2,7) separate, and a volume (9) containing a gas suitable for being heated by the action of the arc, said volume including an opening (10A) to enable the hot gas to escape, characterized in that said blast orifice (10B) and said opening (10A) are disposed side by side and very close to each other.

Abstract: A device preventing the unscrewing of two bodies (2, 3), and in particular of two lengths of a turbodrill, joined end-to-end in threaded union, said device comprising a blocking part (4) which immobilizes the two bodies by means of teeth. The blocking part (4) is provided with two series of teeth, one of which series engages with the teeth of one body and the other with the teeth of the other body.

Abstract: A break chamber for a gas-blast circuit breaker comprising an insulating cylindrical housing (1) containing a fixed arcing contact (5), a fixed main contact (4), and a moving contact (6) passing through one end (3) of the housing. The housing is divided into a first portion (11) and a second portion (12) by a transverse partition. The first portion houses the fixed contacts. The second portion is itself subdivided into two adjacent zones of different diameters. The smaller diameter zone (12A) constitutes a cylinder for a piston (14) in the form of an annular disk fixed to the moving contact. The length of the smaller diameter zone is substantially equal to the length over which said fixed arcing contact (5) penetrates into said moving contact (6) when the circuit breaker is in its closed position.

Abstract: A guide blade set for diverging jet streams in a steam turbine which has blades (2) disposed between a floor plate (3) and a ceiling plate (4) and whose concave and convex surfaces are constituted by substantially rectilinear generator lines (l, m, n), wherein said generator lines (l, m, n) of the blades (2) form an angle of about 90.degree.+.theta./2 with the ceiling plate (4) and with the floor plate (3), where .theta. is the angle of divergence of the jet stream.

Abstract: The device allows the shafts 5 and 20 to be coupled together on a trial and error basis, said shafts being recessed relative to the ends of the stationary stators. The shaft ends have splines 6 and 21 and are coupled by means of a sleeve 22. Before coupling, the shafts are reference marked relative to the stationary portion by means of cams 27 (and 36 which is not shown in the figure) which enter a groove 6 in the shaft 5 and in a groove of the sleeve 22. During the coupling operation, the cams are retracted by a part 37 at the end of a rod 34 which bears against the cam support yoke 35 for the cam 36 in the case of the cam 27 and by the end 48 of the body in the case of the cam 36. The bodies are connected together by a coupling sleeve 9.

Abstract: Valve for adjusting the rate of flow of a gaseous fluid, comprising a valve body (1) having a side inlet (2) and an outlet (3), an obturator (10) movable in translation within a housing (4) and bearing on a seat (18) when the outlet (3) is shut off, said housing (4) being fastened within the body (1) by means (5) located externally of the fluid flow path. The mobile obturator (10) has a front part (9) in the form of a hollow cylinder surrounding with limited clearance a nose-piece (7) attached to the housing (4) by rigid arms within the housing (4). The front surface (17) of the nose-piece (7) extended by the front surface (16) of the obturator (10) and the front part (6) of the housing (4) are of an aerodynamic shape. Reduction of the effects of unsteady forces on the obturator across the full range of openings without head losses when fully open.

Abstract: A solid surface is eroded by directing a liquid axially through a converging passage in a nozzle toward the surface, then deflecting the liquid in a lateral direction parallel to the surface while the liquid is subject to cavitation.

Abstract: A connector for connecting two rotors (2, 4) together, said connector having a plate (1, 3) on the end of each rotor.It has clamping bolts (5) and a plurality of fixing components (6) for the plates (1, 3). Each fixing component (6) has a sleeve (17) cut in two. The sleeve is cylindrical on the outside and conical on the inside and is disposed in precision-reamed bores (12, 14) of the same dimensions in the two plates, the bores of one plate facing and being situated exactly adjacent to those of the other when the rotors (2, 4) are aligned. A shank (20) which has a conical portion (21) pushes back the parts of the sleeve (17) against the walls of the bores (12, 14) thus connecting the plates together without play.In the case of normal operation, the connector has high resistance to shearing due to the fact that there are no stresses in the components (6). In the case of a torque greater than the normal torque, the parts of the sleeve 17 are deformed but can be very easily extracted.

Abstract: A larger number of keys (L) are formed in the outer cylindrical surface of a rotor rim than is strictly necessary for fixing pole pieces (P) thereto. The keys are regularly spaced around the rim. This arrangement makes it possible to avoid having adjacent rim segments offset to each other by an angle which is equal to the pole pitch or at best to the half pole pitch as has previously been the case. The overlap between segments may now be at the pitch of the fixing keys. This can be used to increase the overlap factor, thereby increasing the mechanical strength of the rim against centrifugal forces.

Abstract: The protection device comprises two half cages (13, 14) superposed on each other and surrounding the rotor (8) under test. The half cages together constitute a cage with openings between its bars and provided with water cooling in said bars. The cage ensures that the magnetic field generated by a rotor under test with excitation current is stopped within a distance equivalent to the size of the holes between the cage bars. Induced current heating in the cage is kept under control by water cooling, and metal objects outside the cage are substantially protected from the magnetic field by the cage. Air can pass freely through the cage, and the rotor can be observed without removing the cage.

Abstract: An electrical shunt reactor coil comprises a rectangular magnetic frame in the form of two vertical members (1,2) interconnected at their ends by two horizontal yoke members (3,4). The frame members are constituted by respective stacks of magnetic laminations. A central core (7) extends across the middle of the frame parallel to the vertical members, and an electrical winding (6) is situated around the core. The horizontal yoke members are of width L which is less than the diameter of the winding and which is close or equal to the diameter of the central core. Magnetic shunts (20 to 23) are placed across the outside of the horizontal yoke members. The shunts are longer than the width L of the yoke members so that they overhang both sides thereof. The magnetic shunts are constituted by respective stacks of laminations extending parallel to the axis of the central core and at right angles to the laminations of the yoke members.