Gas flow rate control valve for use as a mass flow controller, e.g. in semiconductor manufacture, has a cylindrical choking body arranged within a housing so it can be controlled by external actuators operating through membranes

摘要

Valve unit comprises: a hollow cylindrical housing (2) that is sealed on both of its ends by membranes (8, 9) and has a fluid inlet (5) and outlet (6); a cylindrical choking body (3) that is in contact with the membranes at each end; two valve seat surfaces within the housing wall with which enlarged sections of the choking body interact; and actuators (10, 11) for application of a stroke type movement to the choking body via one or other of the sealing membranes. The invention also relates to a corresponding use of the value unit in a dosing device or a mass flow controller and a method of manufacture of an inventive valve unit.