Abstract: A coupling for coupling together hoses or pipes for a pressure medium is described. The coupling has a coupling sleeve and a nipple insertable in the sleeve. The coupling sleeve has a valve device for opening the flow-through of the pressure medium as the nipple is inserted to its engagement position and consists of a sleeve-shaped front part and a sleeve shaped rear part. The front part is rotatable but axially essentially non-displaceable and joined to the rear part by means of a resilient lock ring. The valve device also has a valve body in the form of a sleeve, a valve seat for cooperation with the valve body and a blocking sleeve for cooperation with the nipple upon insertion thereof.

Abstract: A valve arrangement for a pressure fluid, particularly high-pressure oil, has a valve housing (10, 90, 190) with an internal, cylindrical sealing surface (16, 100, 160) which forms a guide for the outer, cylindrical sealing surface (42, 107, 162) of a piston body (18, 106, 138). There is provided a circular groove which accommodates a sealing ring (46, 64, 108, 164). An axially displaceable valve sleeve (30, 70, 122, 156) is disposed coaxially with the two cylindrical sealing surfaces(16, 42, 100, 107, 162, 160) and has a cylindrical valve-sealing surface (40, 74, 124, 158). This valve sleeve is biased by a spring (34, 80, 118, 172) such that one end (36, 82, 126, 174) abuts substantially sealingly a seating (38, 86, 128, 176) at that end of the sealing surface such as to form a closed gap (41, 86, 130, 178) at one end of a channel (32, 73, 132, 145).