Connection device for pipe lines

A connection device for pipelines comprising:

• a connecting element having a receiving opening for a pipeline to be inserted with a line end a retaining element mounted inside the receiving opening to lock the line end against extraction, wherein the retaining element is configured as a spring-elastic toothed ring with an outer circumferential area and with a plurality of retaining teeth arranged over the circumference extending radially inward and at an angle in the direction of insertion X and acting positively and/or frictionally against the line end, the toothed ring is mounted with its outer circumferential area having an axially limited freedom of movement defined by a first contact section and a second contact section axially opposed to the first contact section, wherein the toothed ring interacts at a transition between the outer circumferential area and the retaining teeth with a circumferential tilting edge provided inside the connecting element such that on insertion of the line end and contact with the retaining teeth, the toothed ring pivots around the tilting edge in a seesaw manner from a position where the outer circumferential area is pressed against the first contact section until the outer circumferential area contacts the second contact section, wherein the retaining teeth protruding radially inward over the tilting edge can be elastically deformed by bending.