Diaphragm operated process flow valve

Abstract

The present invention is directed towards a diaphragm actuator valve with a keeper element for controlling the number of active coils in the actuator spring, thus controlling the spring tension. The apparatus is a diaphragm operated process flow valve, the valve comprising a valve body and an actuator. The valve body is made up of a valve stem, a valve plug, and the valve seat. The actuator is made up of a diaphragm element operatively associated with a valve stem, which in turn engages the valve plug and seat. An actuator spring having a plurality of spring coils is used to apply pressure against the diaphragm and valve plug. The actuator spring has a terminal coil adjacent to the diaphragm, and the diaphragm acts upon the valve stem against or with the pressure of the spring depending on how the spring is configured. A housing with an internal profile surrounds the spring. The internal profile is used for locating a keeper element at various positions within the housing, engaging the spring at a chosen position. The location of the keeper element is chosen to adjust the spring sensitivity, which in turn adjusts the sensitivity of controlling the valve plug against the valve seat.

Dependencies are inferred from the claim text.