Abstract: The present invention concerns a device for extracting a sample of fluid from a hydraulic circuit having an extraction take-off, for detection of impurities.The device comprises in particular a body (10, 12) provided with a ferrule (14), capable of fitting on the take-off; a perforator (22) fixed on the ferrule (14) and provided with at least one orifice capable of distributing the fluid into the body; a carrier (26) capable of receiving a container (32) provided with a perforatable capsule (36) and a filtering membrane (40), the carrier being displaceable from one to the other of two positions, comprising an extraction position where the capsule (36) is perforated by the perforator (22) and where the fluid penetrates into the container (32), and a non-extraction position where the capsule (36) is not perforated by the perforator (22), and where the fluid runs out outside the container (32).

Abstract: A device for constituting in the wall of a pipe an optical pick-up window which may be scavenged by a protective fluid. A chamber is provided with an inlet for said fluid and an outlet for said fluid, said chamber passing through said wall and opening into said pipe through an open end, the opening of which constitutes said outlet, and a tube introduced into the chamber so as to constitute in the chamber about the tube an annular conduit starting near the said inlet of the chamber and leading towards said outlet, one end of the tube being provided with said window and being placed in the chamber opposite said outlet, the other end of the tube opening outside the chamber, wherein the distance between the window and the outlet is sufficiently short for the flow of protective fluid in front of the window to be a sheet of fluid.

Abstract: The invention relates to a device for assembling stacked annular filtering elements under constant pressure. The device comprises a support which provides an abutment for one end of the stack of filtering elements, a presser member which provides an abutment for the other end of the stack, and a calibrated spring which biases the presser member towards the support while trapping the stack of elements between the two abutments. The device is useful for the manufacture of filters used particularly for the filtration of oils.