Abstract: The control valve is applied to a shock absorber, which comprises: a pressure tube (10); a piston (14) dividing the pressure tube (10) in compression and traction chambers (CC, CT) communicating with each other through the piston (14); a hydraulic fluid reservoir (20) provided with a selective bidirectional fluid communication with the compressor chamber (CC). The control valve (VC) communicates the traction chamber (CT) with the reservoir (20) and comprises a tubular body (40) provided with at least one radial passage (41) opened to the interior of the tubular body (40) and to the reservoir (20); a shutter pin (60) to be axially displaced within the tubular body (40), between a closing position and different open positions of the control valve (VC) for communicating the traction chamber (CT) with the reservoir (20); and an actuator means (A) for axially displace the shutter pin within the tubular body (40).

Abstract: A method and apparatus for coating piston rings by producing droplets of molybdenum and stainless steel from these materials in wire form which are sprayed, preferably in equal amounts to coat the outer surfaces of the rings. A plurality of rings are mounted on a body which are moved in a helical path during the spraying. A nozzle is used having a central passage through which the wire is fed and two sets of passages, one set for an oxy-acetylene mixture and the other for compressed air, with the outlet orifices of the two sets of passages arranged in concentric rings around the central passage outlet orifice.