Overrun barrier, particularly for exhaust gas aftertreatment system for reducing nitrogen oxide in exhaust gas of internal combustion engine, has pressure line, injection port and storage chamber, in which valve element is received

摘要

The overrun barrier (10) has a pressure line (14), an injection port (16) and a storage chamber (19), in which a valve element (42) is received for opening and closing a valve seat (40). A liquid storage (36) is received between an air volume (34) and the storage chamber filled with reducing agent (52). The freezing point of the liquid storage lies above the freezing point of the reducing agent. The storage chamber is separated by a membrane element (24). The valve element has a piston element (22) which is guided in a guide (20) that acts as damping element.