Abstract: A fast-fit coupling for a fluid circulation system comprising at least two conveying members of a fluid. The coupling comprises: a receiving body for each conveying member; way for fastening carried by the body, shiftable by the conveying member during the insertion of the conveying member, and integral with the conveying member when the conveying member is moved in a disconnection direction from the body; way for locking cooperating with the way for fastening to lock the conveying member in a position inside the body and to prevent the body itself from being disconnected; and way for releasable constraint, activatable for restraining the way for locking to the body and preventing the conveying member to be disconnected, and deactivatable to disconnect the way for locking and allowing the conveying member to be disconnected; the way for locking and the body are engageable/disengageable by ways of a relative rotation less than ninety degrees.

Abstract: An ON/OFF valve (1,1?,1?) that has an outer body (3) defining a fluid flow cavity (2) divided by an intermediate surface (8, 21) into a first and a second chamber (2a, 2b) communicating with each other via an opening section (6, 28) in the intermediate surface (8, 21). A flexible shutter (7) has on the side facing the first chamber (2a), a membrane portion (17) that cooperates elastically, by virtue of a fluid pressure, with the intermediate surface (8, 21) and with the opening section (6, 28) to separate the first and second chamber (2a, 2b) hermetica1ly. Fluid leakage generating members (20, 27) are located between the membrane portion (17) of the shutter (7) and the opening section (6, 28), and are active when the pressure in the first chamber (2a) exceeds the pressure in the second chamber (2b) by an amount equal to or less than a threshold value (P) other than zero.

Abstract: A connecting member (4) for a fast-fit safety coupling (1), having a tubular main member (10) connectable to a first conduit (2) for conducting pressurized fluid; a valve member (11) fitted inside the main member (10) to slide axially between a first work position separating the first conduit (2) in fluidtight manner from the outside, and an open second work position; first retaining means (18) for releasably connecting an endpiece (5) of a second conduit (3) to the valve member (11); second retaining means (17) for releasably connecting the valve member (11), in the second work position and connected to the endpiece (5), to the main member (10); and control means (70, 71, 72, 54) for disconnecting the connecting member (4) and the endpiece (5).

Abstract: A quick-coupling joint for pipes comprises a female coupling element and a male coupling element, both of the elements being provided with spring-loaded shut-off valves for automatically terminating the flow of fluid through said coupling elements whenever they are disconnected, the valves being automatically shifted to their open positions when the coupling elements are connected. The spring for the valve of the male coupling element is a helical coil spring having axially spaced coil sections of two different diameters, such that the larger diameter section expands outwardly and firmly embraces axial ribs formed in the flow passage of the male element so as to anchor the spring, and the lesser diameter section biases and moves with the valve element. The male element valve is guided axially by the axial ribs, which form flow passages about the valve when in the open position.