Patent ID: 6837785
Filing Date: 2005-01-04
Classification: H05K

Abstract:
1. A check valve for preventing back-flow of fluid, comprising: a frame; a plurality of adjacent parallel pivot axes mounted in the frame; and a plurality of adjacent vanes, each of the vanes being pivotally mounted to an associated one of the parallel pivot axes, and pivoting between an open position and a closed position; wherein the pivot axes extend generally transverse to the direction of fluid flow through the valve, and each pivot axis is offset from the center of gravity of its associated vane so that fluid flowing through the valve in an allowed direction moves the vanes toward the open position, and fluid flowing in a blocked direction moves the vanes toward the closed position; and wherein the pivot axes are inclined at an angle (α) measured from a vertical reference, thereby causing vanes that are in at least a partially open position to be urged by gravity to pivot towards the closed position.