Abstract: The invention relates to a method of controlling an optical characteristic of a material and it is concerned also with devices and image-forming means for carrying out the method.The method of control is particularly advantageous in devices comprising a plurality of points distributed in the form of a matrix. The optical characteristic K of the material is controlled by an energization having a magnitude G for a duration t, the values G and t being so selected as a function of the time response K (G, t) of the characteristic K at an energization stage of magnitude G that K (G.sub.O, t.sub.O) is equal to K.sub.O.

Abstract: In the manufacture of metal and alloy powders in the form of small diameter spheres whose shape and diameter must be maintained within narrow limits, a substantially cylindrical solid electrode of the material from which the powder is to be made is rotated at high speed about its longitudinal axis and one end of the electrode is heated to fusion point, the molten material being sprayed therefrom under centrifugal forces in the form of small diameter spheres, wherein fusion of the one end of the electrode is obtained by means which produce a local fusion zone on the end surface of the electrode and means for causing the local fusion zone to move along a spiral path on the end surface of the electrode as the electrode rotates.

Abstract: The invention concerns an apparatus for establishing an anchorage in the of a liquid. The apparatus comprises essentially a substantially hollow structure into which solids from the liquid bed are induced as solids in liquid suspension. When the apparatus is being used as an anchoring device the design is such that as solids from the liquid bed are induced into the substantially hollow structure they fill or partially fill the structure which then proceeds to bury itself into the liquid bed thereby establishing an anchorage.

Abstract: Asymmetrical potential wells are created in surface zones of a first doped semiconductor forming a substrate and are of greater depth at the downstream end than at the upstream end in order to ensure unidirectional transfer of the minority carriers. Regions localized at one extremity of the surface zones and constituting the potential wells are formed by a second semiconductor having a forbidden band width which is different from that of the first semiconductor.

Abstract: There is disclosed a device for ameliorating the effects of an extrudate jam of an entrance sizing aperture into a cooling chamber, the extrudate being provided by an extrusion process apparatus associated with the cooling chamber. More specifically, the cooling chamber includes a plurality of serially disposed, longitudinally spaced sizing discs for successively sizing the extrudate. The sizing discs are removably mounted within a tray and upon a jam or a break of the extrudate, the sizing discs may be readily removed through a door within the cooling chamber, to permit rapid cleaning thereof, thus minimizing the shut down time of the extrusion process apparatus. Further, there is disclosed a pneumatic drive cylinder whereby upon detection of an outsized extrudate, the drive cylinder is actuated to move the assembly of the tray and its plurality of sizing discs in the direction of the movement of the extrudate.

Abstract: Bulk handling apparatus which includes an elevator carried by a vertical support arm movable about its axis and horizontally, the arm itself mounted on a lifting mechanism, a discharge device for elevated material, and a guide device on the arm on the same side as the rising run of the elevator which device during horizontal travel of the arm will preset material to be elevated to the elevator.

Abstract: A cooling circuit for the main reactor vessel is limited on one side by the main vessel and a flow-reversing baffle shell and on the other side by the flow-reversing baffle shell and a counter-baffle shell which surrounds the primary vessel. The cooling circuit is supplied with a fraction of the cold liquid metal which is present within an intervessel space between the counter-baffle shell and the primary vessel. An annular chamber is located above the cold liquid metal and filled with an inert gas at a pressure which maintains the gas/liquid metal interface below the top of the flow-reversing baffle shell.

Abstract: In a system of stationary collectors which are connected together in series and differently oriented with respect to the sun, a heat-transporting fluid is circulated from the collector which is least exposed to solar radiation to the collector which is the most exposed to solar radiation. The direction of flow within the collectors is reversed at a moment of the day which is determined beforehand so as to control the quantity of energy delivered by the collectors.

Abstract: A spring system mounted on a supporting bar which is rigidly fixed to an element of a remote manipulator is continuously applied against the motion-transmission belts or cables with a substantially constant force in order to take up the slack of these latter. The spring system is constituted by a series of parallel leaf-spring elements equal in number to the cables or belts to be tensioned, each element being constituted by an auxiliary spring-leaf applied against a main spring-leaf. A bridge-piece is fitted at the end of the main spring-leaf and mounted astride the corresponding belt or cable.

Abstract: In a liquid crystal whose molecules have temperature-dependent dielectric anisotropy within a range such that the liquid crystal retains the same phase, the optical properties of a liquid crystal film are controlled by applying an electric field of predetermined frequency to the film and by bringing the temperature of the film to a value within the range mentioned. The dielectric anisotropy then assumes a predetermined value in respect of said frequency and the liquid crystal film assumes a predetermined optical state.

Abstract: An apparatus for positionally controlling the movable head assembly of a magnetic disc memory unit. In a first state, the head assembly is accelerated under substantially free conditions. In a second or deceleration state, the assembly speed is compared with and regulated by a series of theoretical speeds set in accordance with the actual speed attained by the movable head assembly during the first state.

Abstract: Iron minerals are reduced in solid state in a vertical shaft furnace by gases produced in the furnace fed at the top with a mixture of minerals and solid reducing material. A combustion gas including oxygen is injected at low velocity and in finely divided form in the medial part of the furnace. Combustion gases produced in the furnace transfer heat as determined by the combustion with oxygen and are removed at the top of the furnace and recycled to the bottom of the furnace. The amounts of materials, the amounts of gases aspirated and the amounts of oxygen are adjusted so that the gases and materials leaving the top of the furance and in the bottom of the furnace are at low temperature.

Abstract: A seal emplacement tool for emplacing flexible ring seals, and including a tube having an open end and for accommodating a folded seal, a plunger in the tube for ejecting the seal from the open end, and a guide externally of and so spaced from the said open end as in use to deflect a seal radially outwards from the plunger axis.

Abstract: The system comprises an assembly of uniformly spaced horizontal plates extending parallel to a horizontal closure surface, an outer shell and a thick bottom plate suspended from the horizontal surface by means of spaced suspension members attached to the horizontal surface and to the thick plate respectively. The thick plate supports stacked metallic plates held in spaced relation and protected by a lateral shell which is capable of free expansion at the upper extremity and joined to said thick plate in leak-tight manner.

Abstract: This invention relates to means for cooling the top end of a suspended vessel such as the pressure vessel of a nuclear reactor.The invention consists in supplying a liquid coolant which flows through coils located in contact with an intermediate heat conducting material which is in contact with the top end of the vessel. The liquid coolant or the intermediate liquid may be of liquid metal such as a sodium-potassium alloy and the intermdiate material may be contained in a tank rigidly secured to the vessel.In modified arrangements the intermediate material may be a solid or a gas.

Abstract: A hydraulically actuated driving tool is provided with a ground engageable member which is driven into the ground by the action and reaction of a drive mass which is free to slide within the tool and which is repetitively forced away from and back to the ground engageable member in a manner determined by a hydraulic control system. Each repeated cycle of operation engenders two separate forces to drive the ground engageable member into the ground, one being the force exerted by high pressure fluid in the hydraulic control system when the drive mass is forced away from the ground engageable member and the other being the force exerted when the drive mass impacts back upon the ground engageable member. A switch means is provided whereby the returning drive mass initiates the next cycle of operation of the hydraulic control system.

Abstract: The disclosure describes improved apparatus for setting the states of storage elements in a data-processing system and for responding to the data read out of the storage elements. The apparatus includes a first error detector which enables an initial setting circuit to initially set a first storage element to a predetermined condition in response to an error. The initial setting circuit also disconnects the outputs of a second storage element while that element is receiving reference data and reconnects the outputs of the second storage element after the data has been written into that element. A second error detector monitors the outputs of the first and second storage elements as test signals are conducted to the storage elements.

Abstract: A radiation filter, for a gas detector, comprising an optical interferome having in each of first and second physically separated optical paths therethrough a gas cell containing a quantity of the gas to be detected; there being a difference in pressure between the quantities of gas in the two gas cells; the gas cells being of substantially equal lengths in the direction of the optical path therethrough; and the interferometer being arranged so that in the absence of the gas cells there is zero path difference between the said first and second optical paths through the interferometer.

Abstract: In a follow-up servo system for the electrical control of a friction clutch of, say, a motor vehicle from the throttle control by way of an electro-mechanical actuator, with automatic take-up of the wear of the mating friction surfaces, whenever the clutch plate (i.e. the axially-movable part) is in its fully-engaged (FE) position with respect to the cooperating axially-fixed part a signal is repetitively derived to represent the corresponding just-touching (JT) position of the plate under the then conditions of wear. To this signal is added a signal from the throttle control within a range corresponding to the JT-FE range of the plate, thereby forming a demand signal corrected for wear. From a comparison of it with a measurement signal representing the actual position of the plate an error signal is derived for application to the actuator in the appropriate sense.

Abstract: In a method of reduction of a mineral on a continuous moving grate, the material layer is passed through a plurality of processing zones of the grate on a layer of chemically inert material and the gas flows through the layers in the zones alternate between a downward direction and an upward direction to limit the temperature of the grate and to use the heat taken up by the inert layer to heat the processing gases.