Abstract: The subject composite materials comprise an association of an organic elastic matrix with a network of non-oxidized quasi spherical particles, of submicronic dimension and of a diameter ranging between 0.1 .mu.m and 10 .mu.m, distributed uniformly in the matrix.The materials are intended to coat pieces subjected to the phenomena of wear, erosion, cavitation and abrasion notably in a corrosive medium.According to a method of manufacture of these composite materials, the nonoxidized submicronic particles are, immediately before their introduction in the organic matrix, plunged into an organic macromolecular dispersant chosen of such type that the macromolecular chains of the dispersant are fixed on the surface of the particles by noncovalent bonds.

Abstract: The subject composite materials comprise an association of an organic elastic matrix with a network of non-oxidized quasi spherical particles, of submicronic dimension and of a diameter ranging between 0.1 .mu.m and 10 .mu.m distributed uniformly in the matrix.The materials are intended to coat pieces subjected to the phenomena of wear, erosion, cavitation and abrasion notably in a corrosive medium.According to a method of manufacture of these composite materials, the nonoxidized submicronic particles are, immediately before their introduction in the organic matrix, plunged into an organic macromolecular dispersant chosen of such type that the macromolecular chains of the dispersant are fixed on the surface of the particles by noncovalent bonds.

Abstract: The finishes of the present invention consist essentially of metal alloys having the general formula:T.sub.a Cr.sub.b Zr.sub.c B.sub.d M.sub.e M'.sub.f X.sub.g I.sub.h(I)in which a+b+c+d+e+f+g+h=100 atomic percent;T is Ni, Co, Ni--Co or any combination of at least one of Ni and Co with Fe, wherein 3<Fe<82 at. % and 3<a<85 at. %;M is one or more elements of the group consisting of Mn, Cu, V, Ti, Mo, Ru, Hf, Ta, W, Nb, Rh, wherein 0<e<12 at. %;M' is one or more rare earths, including Y, wherein 0<f<4 at. %;X is one or more metalloids of the group consisting of C, P, Ge and Si, wherein 0<g<17 at. %;I represents inevitable impurities, wherein h<1 at. %, and 5.ltoreq.b.ltoreq.25, 5.ltoreq.c.ltoreq.15, and 5.ltoreq.d.ltoreq.18.Powders obtained from these alloys that are deposited on substrates by thermal projection provide finishes having increased hardness in addition to high ductility and excellent resistance to corrosion.

Abstract: The press comprises a frame (1), a feed zone (3) for receiving the waste products, a pressing chamber (9) comprising an inlet opening (10) and an outlet opening (11) which are in opposed relation and disposed coaxially relative to the feed zone (3), and a chamber (14) for discharging the solid phase. The press further comprises an element (15) which is movable transversely relative to the axis of the press chamber (9) between a first position for closing the outlet opening (11) and a second position for opening the outlet opening (11), and an arrangement (20) for applying the movable element against the outlet opening (11) of the pressing chamber.

Abstract: The press comprises a frame (1), a feed zone (3) for receiving the waste products to be treated, a press chamber (9) comprising an inlet opening (10) and an outlet opening (11) which are opposed and disposed coaxially relative to the feed zone (3), and a chamber (14) for discharging the solid phase. The press further comprises an element (15) which is transversely movable relative to the axis of the press chamber (9) between a first position for closing the outlet opening (11) and a second position for opening the outlet opening (11), and an arrangement (20) for separating leakages of the liquid phase from the solid phase in the discharge chamber (14).

Abstract: The press comprises a frame (1), a feed zone (3) receiving the waste to be treated, a pressing chamber (9) comprising an intake aperture (10) and an outlet aperture (11) and a chamber (14) for discharging the solid phase. The press also comprises a component (15) movable transversely relative to the axis of the pressing chamber (9) between a first position for closing off the outlet aperture (11) and a second position for opening the outlet aperture (11), comprising jacks (20) for horizontal movement of the movable component in the direction of the axis of the pressing chamber (9) in order to apply the face of the movable component facing the outlet aperture (11) against the outlet aperture during compression of the heterogeneous waste.

Abstract: The reproducing system 9, 10, 42, 43 controls rotation of the rotor 30 of the electric motor 28 in order to provoke a variation in the leakage of the leakage relay 33 with a view to varying the position of the piston 2 of the jack 1. The stator 34 of the motor 28 is connected by a mechanical link 36 to the piston rod 2a of the jack 1. In the event of no-voltage, the brake 29 of the motor acts in order to connect the rotor 30 and the stator 34. The position of the rod 2a may then be varied by mechanically rotating the rotor-stator assembly 30-34 by a crank 41.

Abstract: An apparatus for rotating structures such as large antennas which incorporates a motor for controlling rapid rotation of the structure through a ring gear and a screw jack which is selectively coupled to the ring gear for controlling a slower more exacting rotation of the structure about a common axis.

Abstract: This invention relates to a sealing device ensuring lateral tightness of a weir gate with respect to the corresponding lock wall, of the type comprising a lip disposed over the whole length of each lateral face of the gate and a rounded rib extending the leading face of said gate, wherein the rounded rib projects transversely beyond the plane of the lock wall, so that its periphery, which takes a circular form, comes into abutment against the lateral face of a cylindrical chamber made in the lock wall. In this way, the displacements of the gate do not affect tightness.

Abstract: A buffer device for the spiral housings of water turbines wherein the housing includes an extension located along the axis of the inlet conduit into the housing and wherein a hydraulic cylinder and piston assembly is disposed between the extension and a fixed support with a fluid conduit extending between the housing and the cavity of the hydraulic cylinder and piston assembly.

Abstract: This invention relates to a channel for supplying water to a vertical-axis Kaplan water turbine, wherein the vertical side walls thereof are oriented in convergent manner in order that, at turbine level, they join an end face of rounded form, of which the radius of curvature is slightly greater than the radius of the guide blades located above the turbine and the sleeve of the turbine shaft and/or an inclined fixed wall downstream of the turbine are provided, for preventing the development of suction eddies downstream of the sleeve of the turbine shaft.

Abstract: This invention relates to an improved device for reducing the lag of position of a non-linear copying system or subsidiary controller for a regulation loop, which comprises a comparator establishing the difference which enters in a multiplier from which emerges a signal sent into another comparator elaborating the difference between this signal and the difference between the frequency and the frequency reference, so that the output of this comparator is introduced into the integral action circuit of the subsidiary controller.

Abstract: The inventive control system introduces the current (.DELTA.I) and voltage (.DELTA.C) deviations simultaneously with the injection set point (C) to define a new injection set point (C') that is utilized in conjunction with the measurement of diesel engine speed (V.sub.rD) to adjust the injection and with the measurement of the injection flow rate C.sub.r to adjust the generator excitation current.

Abstract: Low-head hydroelectric installation, in particular for a tidal power station, intended to operate under variable heads of water that can fall to values in the region of zero. When the head of water is lower than a defined value (Hd), lower than at least half the nominal head (Hn), the turbo-machine (1) is made to rotate at a speed (n1, n2, n2, . . . ) lower than the synchronous speed (ns) and bringing its efficiency near to the heart of the efficiency contours. For this purpose, a frequency converter (7) is inserted between the rotary electrical machine (3) and the network (4), the converter (7) being constructed for a power in all cases lower than at least half the nominal power (Pn).

Abstract: A hydrostatic bearing supplied with pressurized water positioned as a seal between the shaft of a pump-turbine and a suction bend adjacent the lower end of the shaft. The hydrostatic bearing replaces the conventional labyrinth joint usually located above the lower shaft bearing, and may additionally replace the lower bearing itself.

Abstract: A propeller runner having swivelling blades, each integral with a journal engaged in two bearings respectively in the outer portion and the inner portion of the runner, and equipped with lateral connecting rods for manipulation in rotation.The inner central portion of the hub of the runner includes a spider 29 each arm of which consists of a radial journal 31 prolonged by a threaded portion 32. Each blade journal 23 is engaged over a spider journal 31 with a bearing 26 and is held by a nut 33 screwed onto the portion 32 with the interposition of a thrust bearing 30. The spider 29 for a four-bladed runner preferably consists of a core 39 through which passes a shaft 40.The invention is applicable to propeller runners having swivelling blades for turbines.

Abstract: A method of tracking for telecommunications antennae.It consists in carrying out continuous measurements along each axis (X,Y) of displacement and in returning backwards by a measured amount before proceeding to change the axis.

Abstract: A tubular obturator for use with a hollow body e.g. a pipeline or cylindrical container, terminating in a cylindrical opening for closing the opening when it is desired to subject the body to a pressure test, comprises a cover, the diameter of which is slightly smaller than that of the opening of the body to be tested, and a cylindrical skirt extending from the cover and comprising a plurality of strips.

Abstract: Method of starting pumps, in particular a method of starting turbopumps functioning as pumps, the said pumps or turbopumps being of the type with a fixed distributor-diffuser, and in which the curve of variation of the power at working speed as a function of the flow of fluid passes through a minimum which is between the zero-flow point and the nominal-flow point.

Abstract: A mechanism for controlling two rotatable cut-off devices which are mounted in series in a shell for connection to one and the same pipe, comprises a jack in respect of each cut-off device, each jack being articulated to a lever fast with a journal of a respective one of the cut-off devices and to the shell in the zone thereof supporting the journals of the other cut-off device.The invention is particularly applicable to the valves for protecting a hydraulic machine in a high-fall hydraulic power station.