Backflow preventer for a sewer line

摘要

The backflow preventer for a sewer line comprises a box-like housing which can be closed at the top side with a cover and which exhibits openings which are provided in walls lying opposite one another, which openings are provided with a connection piece for the ends of the pipe line parts, and one or more shuttle valves which bear, in the rest position, against in each case one valve seat arranged in the housing. In this arrangement, in the region of each valve seat in the housing, only on that side which is directed towards the cover, there is above the valve seat a recessed region in which hinge plates are arranged for a hinge part which exhibits hinge pins which are situated laterally and at a distance from the preventer surface of the shuttle valve directed away from the opening direction of the shuttle valve and towards the valve seat.