In-line valve for administering parenteral liquids

摘要

An intravenous flow control valve includes in-line valving mechanism wherein flow through the valve at low flow settings increases slowly with displacement of a valve controller disc. The disc, which is free to rotate with respect to an axis but is longitudinally fixed, includes a threaded stem which engages a threaded bore and a sluice gate member. The gate member is permitted to move only longitudinally in a valve control chamber in response to disc rotation and includes a control passage defined therethrough which tapers in the direction of gate member motion so as to graduate the cross-sectional area of the passage exposed to flow as the disc rotates. A locking arrangement permits the disc to be positionally locked to avoid inadvertent change of the valve setting. The disc and stem provide an hermetic seal for the valve control chamber to avoid contamination of the intravenous fluid being controlled.