Abstract: A crusher device for performing a crushing operation, including a hollow part of frusto-conical shape narrowing downwardly, a crusher spindle rotatably mounted coaxial with the hollow part, at least one crusher impeller rotatably mounted on the crusher spindle, and a crusher driving device for rotatably driving the at least one crusher impeller relative to the first hollow part; the at least one crusher impeller comprises a first crusher impeller containing a first crushing blade and a second crushing blade, each of the first and second crushing blades extending radially from the crusher spindle and being fixedly connected to each other at their distal extremities by a blade member. The crusher device can be combined with a milling device providing an apparatus of compact size, adapted for reducing material from a size up to 36000 cm3 to particles having a size below 250 microns.

Abstract: A crusher device for performing a crushing operation, comprising a hollow part of frusto-conical shape narrowing downwardly, a crusher spindle rotatably mounted coaxial with the hollow part, at least one crusher impeller rotatably mounted on the crusher spindle, and a crusher driving device for rotatably driving said at least one crusher impeller relative to said first hollow part; said at least one crusher impeller comprises a first crusher impeller containing a first crushing blade and a second crushing blade, each said first and second crushing blades extending radially from the crusher spindle and being fixedly connected to each other at their distal extremities by a blade member. The crusher device can be combined with a milling device providing an apparatus of compact size, adapted for reducing material from a size up to 36000 cm3 to particles having a size below 250 microns.

Abstract: A method of making a powder for covering an ingot mold for the continuous casting of steel, in particular steels with ultra-low carbon content. The powder comprises a base powder and particles of at least one metal nitride, its free carbon content being between 0 and 1% by weight, the method comprising forming a slip of raw materials for the basis powder, at least one metal nitride and water and atomizing the slip to form a mist and drying the mist to form granules having diameters lying between 20 &mgr;m and 800 &mgr;m.

Abstract: A powder for covering an ingot mold for the continuous casting of steel, in particular steels with ultra-low carbon content. The powder comprises a base powder and particles of at least one metal nitride, its free carbon content (%C.sub.free) being between 0 and 1% by weight, it being produced by atomization, and having the form of granules of between 20 and 800 .mu.m in diameter. In one application of the invention, the nitride is silicon nitride, and its weight content (%Si.sub.3 N.sub.4) is equal to: %Si.sub.3 N.sub.4 =0.5-0.28.times.%C.sub.free .+-.0.10.

Abstract: A method and device for adjusting at least one parameter conditioning at least partially the operation of an internal combustion engine with controlled ignition, this technique using the detection of the passage of the flame front in the combustion chamber. From the distribution or histogram based on several of these angular divergences corresponding to a predetermined number of cycles n, a magnitude is elaborated or determined for controlling the operation of the engine and the parameter conditioning the operation of the engine is modified so that the control magnitude takes on a predetermined value.

Abstract: In a nuclear reactor protection system, the control device initiates reactor shutdown when the amplitude of a voltage signal delivered by a detector oversteps a range limited by two adjustable values. The device comprises a stabilized supply, a detector supplied by a rectifier for delivering a d.c. voltage having an amplitude Ve which is proportional to the value of the signal to be measured, two generators for producing d.c. voltages of opposite sign having amplitudes Vd and Vref, and an adjustable voltage divider which delivers a periodic rectangular-wave voltage having an amplitude Vs. The detector output voltage is compared with the algebraic sum of the values Vd, Vref and Vs by means which produce a voltage level of 0 if the amplitude Ve is outside the range (Vd + Vref, Vd + Vref + Vs) and a voltage level of +1 if the amplitude Ve is within said range.

Abstract: An electronic unit for controlling the safety absorbers of a nuclear reactor comprises a self-supplied AND.sub.1 circuit for performing logical multiplication of input signals each capable of assuming one out of two values, series-connected modules each constituted by a dc/ac converter, the output of the last module being coupled to the first converter and to a regulator input at which is obtained a logical a.c. signal whose value corresponds to the result of multiplication of the different input signals, a static intensity regulator with negative current feedback for modulating the width of the square waves delivered by an isolation transformer, a rectifier for delivering a constant current to a load impedance.