FLOW-CONTROL VALVE SYSTEM

摘要

A valve for controlling intravenous fluid includes a flexible membrane (11), which together with a rigid body (21) forms a valving chamber (29). Two mouths (27, 32) lead into and out of the valving chamber. In one embodiment, a stem (23) having an enlarged portion (15) is attached to the membrane's inner face and extends into the outlet mouth. Fluid pressure on the inner face causes the enlarged portion of the stem to press against a narrower portion (38) of the outlet conduit, thereby preventing flow through the oulet conduit. External pressure on the membrane's outer face causes the enlarged portion of the stem to separate from the outlet conduit's walls, thereby permitting flow through the outlet conduit. In another embodiment, a groove (43) is placed near one of the mouths. The membrane may be pressed against the rigid body and the groove, so as to prevent flow except through the groove and to variably restrict flow through the groove.