Patent ID: 7850210

Claim:
A plug-in coupling for fluid systems, having two coupling parts connectable to one another, the coupling comprising: a first coupling part and a second coupling part, each of the coupling parts including respectively first and second interengaging catches for connecting the first and second coupling parts together, one of the first and second coupling parts including an end union section by means of which the one of the first and second coupling parts can be plugged into the other of the first and second coupling parts, the first coupling part further including at least one end retaining section having the first catches configured to form a connection by gripping a peripheral contour of the second coupling part which forms the second catches, a separate release part provided on at least one of the two coupling parts for separating the connection between the first catches of the first coupling part and the second catches of the second coupling part by means of outward radial resilient expansion movement of a first portion of the release part into an expanded position in response to inward radial resilient movement of a second portion of the release part under the effect of a manual pressure, the release part being held in a fixed axial position on the at least one of the two coupling parts during separating of the connection between the first and second catches and the release part including a flexibly resilient material effecting a return from the expanded position, if the manual pressure is withdrawn, wherein the release part has at least two opening sections forming the first portion, at least one operating section forming the second portion and at least two pressure transmitting sections, each of the pressure transmitting sections linking an opening section to the at least one operating section, so that the release part is generally fork shaped, and wherein the first catches are formed from two diametrically opposing resilient expandable retaining arms of the retaining section, which are integrally formed onto a tube length of the first coupling part.