of the pipes of which the coupler ensures join immobilization between these principal and secondary parts occurs by catches borne by the secondary part catching with complementary catches borne by the principal part application_number US 71204903 A description referring now to the drawings the coupler shown in fig1 to 4 comprises a female element a and a male element or connector b connected respectively to an upstream pipe c 1 and to a downstream pipe c 2 the upstream pipe c 1 is itself connected to a source of fluid under pressure not shown the outside shape of the body 1 of the female element is substantially cylindrical and circular centred on an axis x x u2032 which is also the longitudinal axis of a conduit 11 inside the body 1 and in which is arranged a valve 2 mobile along axis x x u2032 the body 1 is in two parts and comprises a principal part 12 forming a bore 13 in which is immobilized a secondary part 14 fast with the pipe c 1 in practice the valve 2 is mounted in part 14 which defines a groove 141 for receiving an o ring 3 for seal of the valve 2 the outer radial surface.