US Patent 8491012 Quick-connect fluid coupling

A tube coupling including a body having a bore and an open end, a slidably movable jaw ring received in the bore, a bushing fitted into the body open end having a surface facing the movable jaw and defining a stationary jaw, and a resiliently expandable grab ring disposed in the bore between the movable and stationary jaw. With a tube end being inserted into the bore and through the grab ring, and with the tube being grabbed by the grab ring to retain the tube end in the bore, the movable jaw is responsive to fluid pressure received within the tube to slidably move towards the stationary jaw face such that a portion of the grab ring is clamped therebetween.