PIPE COUPLING FOR A VACUUM PIPE LINE

摘要

The present invention relates to a pipe coupling for a central vacuum cleaning pipeline adapted to be connected with at least one pipe to form a central vacuum cleaning pipe line. The present invention also relates to a manufacturing method for the pipe coupling. The pipe coupling comprises at least a first and a second opening defined by an envelope wall, the envelope wall comprises an inner and an outer surface, wherein at least said first opening is arranged to receive a pipe introduced into said first opening along a first insertion and retraction direction, so that the pipe coupling overlap the pipe with a part of the inner surface of the pipe coupling at an attachment section. The attachment section comprises in turn an annular seal member arranged in the attachment section to effectively seal between the inner surface of the pipe coupling and the outer surface of said pipe. The attachment section further comprises an annular recess which defines a stop surface. The annular recess is configured to form a smooth transition between the pipe and the pipe coupling to reduce noise pollution.