Patent ID: 6254576
Filing Date: 2001-07-03
Classification: A61M,G05D,Y10T

Abstract:
A fluid flow regulator comprising a variable outlet defined by a spacing between an outlet aperture and a flexible diaphragm, and in which the position of the flexible diaphragm varies as a function of a pressure differential between a sensing chamber on a first side of the diaphragm and an outlet chamber on a second side of the diaphragm, an adjustable flow impedance configuration being disposed in a flow path passing from a first point in substantially direct fluid communication with said sensing chamber to said outlet chamber, the ajustable flow impedance configuration including:(a) a first element providing a first substantially cylindrical outer surface, said first cylindrical surface defining a central axis; and(b) a second element providing a second substantially cylindrical inner surface deployed coaxially, and in sliding contact, with said first surface,wherein at lease one of said first and second cylindrical surfaces features at least one groove configured to define a flow-attenuating passageway between said first and second cylindrical surfaces, said flow-attenuating passageway having a net flow vector substantially parallel to said axis,said first and second elements being configured such that axial movement of said first element relative to said second element causes a variation in an extent of overlap between said first and second cylindrical surfaces, thereby varying an operative length of said flow-attenuating passageway.