Differensialskruesammenstilling for varierende vridningsmoment for ventil

摘要

An assembly for actuating a valve that is in a differential screw assembly when the valve is in a portion of its stroke that experiences high resistance. The actuating assembly is selectively changeable into a direct drive configuration when the valve is in a lower resistance portion of its stroke. A sliding sleeve moves axially within the actuating assembly and has a profile that is strategically dimensioned to change the actuating assembly configuration.