Abstract: The present invention relates to a cutting-off or parting device working by electric sparking, enabling electrically-conductive materials to be cut-off by means of a metallic disc which circulates an electric current, the disc being composed of one or more substances which are electrically conductive during the cutting-off operation and being provided with three or more radial slots formed at the periphery of the disc, the latter being so arranged as to permit the transverse passage of a dielectric cooling liquid from one face of the disc to the other, a first means keeping the disc flat during the cutting operation and a second means being provided for constantly maintaining an equal radius over its entire periphery. Optimum relations between the dimensions of the radial slots and the initial radius of the disc are specified. The disc may be perforated or may be made from sintered or cellular products.

Abstract: This invention relates to a device adapted to be attached to a conventional transfusion tube of a blood-transfusion apparatus, said device permitting the drop-by-drop regulation and control of the flow-rate and comprising a mechanical pump comprising a plurality of rollers rotatably mounted around the periphery of a disc rotatably mounted within a casing chamber, said chamber having the same diameter as the envelope defined by said rollers, said casing having an opening therein and comprising a slidable member in said opening adapted to be biased by resilient means against said rollers, thus permitting the interposition between said slidable member and said rollers of transfusion tubes of different diameters. An air-bubble detector is provided which stops the pump if an air bubble is present in the transfusion tube, and the failure of any electrical or mechanical member actuates an optical and acoustic alarm signal.