Disconnectable coupling

In association with two separable tubes having similar end connectors (10) adapted to abut one another;

• improved means for removably joining the end connectors, comprising a first resilient split ring (18), having radial side surfaces seated in an endless external groove in one of the end connectors for outward radial motion from a contracted position contained within the end connector profile to an expanded position projecting outwardly beyond the end connector profile;
• a second ring (19) having radial side surfaces carried by the other end connector and projecting radially beyond the end connector profile;
• an axially slidable collar (20) mounted on said other end connector for movement between an inactive position spaced from said first ring to a locking position spanning said first and second rings;
• the internal surface of the collar defining a first land area (21) at one end of the collar, a second land area (23) at the other end of the collar, and an intervening internal groove (25) that has an axial dimension defined by end surfaces that are axially spaced the same as the distance between the rings when the end connectors are abutted together;
• the diameter of each land area being less than the diameter of the second ring and the split ring when said split ring is in its expanded condition, said land areas being sized to ride on the outer surfaces of the end connectors the radial side surfaces of the rings and the end surfaces of the internal groove (25) being normal to the longitudinal axis of the end connectors whereby when the rings are located within the groove the nonadjacent side surfaces of the rings will abut the groove end surfaces so that the collar locks the rings and associated end connectors together;
• and means for depressing said first resilient split ring to enable the collar to move between its inactive position and its locking position;
• said ring depresser means comprising a sleeve (24) encircling said collar for limited axial movement along the collar outer surface, said sleeve having two opposite divergent internal cam surfaces (30, 32) and an intervening land surface (33) on the end of the sleeve nearest said one end connector, whereby when the sleeve-collar assembly is moved to a position spanning the two end connectors one of said cam surfaces (30) depresses said resilient split ring to its contracted position, the collar being dimensioned so that its first land area (21) passes over said split ring while said split ring is being retained in its depressed position by the aforementioned sleeve land surface (33);
• the other cam surface (32) being located closely adjacent the resilient split ring when the collar is in its locking position, whereby movement of the sleeve away from said one end connector causes said other cam surface (32) to move over the resilient split ring to depress same to its contracted position, after which the aforementioned land surface (33) holds the resilient split ring in its contracted position while said sleeve moves the collar so that the first land area (21) passes over the split ring.