Vehicle engine exhaust silencer uses three disk proportionating damper valve wheel whose center disk pivots via threaded rod round axis to vary upward and downward decibel emission levels via outside disk holes.

摘要

In an engine silencer the damper wheel acting as three-disk proportionator valve can be varied so as to vary the decibels in upward and downward directions and in this way vary the decibel levels of the noise emitted to the environment in these two directions. In detail, the valve wheel comes in piston shape in side view made up of three disks of which the center disk can be pivoted round a threaded rod to variously cover the side disk holes.