EXHAUST PASSAGE CONTROL VALVE

摘要

PROBLEM TO BE SOLVED: To prevent such application of overstress to a valve element 21 as results from a reentrant curve thereof to the closing side by a set load on a valve spring 22, in an exhaust passage control valve so constructed that the valve element 21 in the form of a spiral is mounted on a valve seat portion 20a formed in a housing 20 where engine exhaust gas flows and is urged to the closing side by the valve spring 22, and that a given set pressure or above for valve opening of exhaust pressure expands the valve element 21 to the opening side to open the valve. SOLUTION: The housing 20 has a valve closing stop 27 that extends along a plane perpendicular to a plane including the valve seat portion 20a so as to stop a reentrant curve of the valve element 21 to the closing side, when placed in contact with the central portion of the valve element 21.