Valve device

Abstract

A valve device includes: a valve body defining a flow path; a diaphragm as a valve element for opening and closing the flow path; a stem for making the diaphragm separate and seat on a valve seat; a coil spring as a spring member for constantly biasing the stem in a valve-closing direction; a piston connected to the stem; and an actuator body for slidably accommodating the piston, wherein the inside of the actuator body is partitioned by the piston into a pressure chamber to which a driving gas is supplied and an atmospheric chamber communicating with the atmosphere via vent holes formed in the actuator body, and the actuator body includes an adjustment mechanism capable of restricting the ventilation amounts of the vent holes so as to adjust a valve closing time required for valve closing and a valve opening time required for valve opening to be equal.

Dependencies are inferred from the claim text.