MULTI-TEETH ENGAGEMENT IN AN ACTUATOR PISTON

摘要

An actuator for a valve assembly is provided. The actuator has an actuator body and at least one piston configured to travel within the actuator body. The actuator has an output shaft located at least partially within the actuator body and configured to couple to a valve stem of a valve wherein the output shaft has a plurality of teeth protruding from a pinion. The actuator has at least one rack configured to move with each of the at least one piston, the rack having a piston end and a terminal end and wherein the rack has a plurality of rack teeth configured to engage the plurality of teeth on the output shaft. The terminal end of the rack is configured to be maintained a minimum distance beyond an engagement point, wherein the engagement point is located between the rack teeth and the teeth in all operating positions.