Patent ID: 7954860

Claim:
A coupling mechanism, comprising: a coupling main body in a shape of a circular cylinder; a stopper member in a shape of notching a portion of a ring-like strip member; a connected pipe inserted to an inner side of the coupling main body; and an elastic ring for sealing attached to an outer periphery in the vicinity of an inserting front end of the connected pipe, wherein an inner peripheral wall of the coupling main body is inscribed with an outer side ring groove containing an outer peripheral side edge portion of the stopper member, and a stopper member introducing port formed by a width wider than a width dimension of the strip member of the stopper member is inscribed at a position of an outer wall portion of the coupling main body shifted from a position of inscribing the outer side ring groove slightly on a side of an inserting front end, wherein the stopper member is brought into a state of being applied with a spiral torsion such that both end portions opposed to each other of the strip member of the stopper member carry out a core deviation slightly, wherein an inner peripheral wall of the outer side ring groove is formed by a taper face in a state of being expanded from a rear end side to a front end side in an inserting direction, and also an outer peripheral wall of the stopper member is formed in a taper face of a shape in correspondence with the taper face of the outer side ring groove, and wherein the inner peripheral wall of the stopper member is formed in a state of being substantially in parallel with the outer peripheral wall of the connected pipe and a face of the inner peripheral wall is formed by a rough face achieving a slip preventing effect.