Patent ID: 7651139

Claim:
A coupling for use with a fluid line arrangement and defining perpendicular axial and radial directions, said coupling comprising: a coupling part having at least one sealing ring; an insert part sealingly insertable into said coupling part along an insertion direction; said sealing ring further comprising: a radially outwardly facing, planar outer side contacting a planar support surface of said coupling part; and a radially inwardly facing, arcuate inner side extending between edge faces of said planar outer side, said sealing ring having a semicircular cross section; and said coupling part further comprising: a retaining collar disposed axially in front of said planar support surface with respect to the insertion direction, said retaining collar projecting radially inwardly beyond said planar support surface and having an obliquely upwardly sloping front wall and an obliquely downwardly sloping rear wall, each with respect to the insertion direction, said retaining collar further comprising a front wall and a rear wall with respect to the insertion direction, said front wall more steeply pitched than said rear wall; and a step projecting axially against the insertion direction and including a rear contact surface, said planar outer side and said arcuate inner side of said sealing ring disposed between said retaining collar and said rear contact surface.