Patent ID: 7832431
Filing Date: 2010-11-16
Classification: F04B,F16K,Y10T

Abstract:
1. A valve comprising: a flexible tube having first and second end portions defining an inlet and an outlet, respectively; a rigid valve body surrounding the flexible tube, the end portions of the flexible tube being sealingly fixed to the valve body to define an enclosed space between the exterior of the flexible tube and the interior of the valve body; a fixed volume of a substantially incompressible fluid filling said enclosed space; wherein the arrangement is such that, when the pressure at the outlet is greater than the pressure at the inlet, the flexible tube adjacent the outlet moves outwards displacing some of the fluid from the outlet region towards the inlet region so that the flexible tube is compressed in the region adjacent the inlet and the flexible tube is substantially collapsed so as to close the valve or allow severely restricted flow; wherein, when the pressure at the inlet is greater than that at the outlet, some of the fluid is displaced from the inlet area towards the outlet area so that the flexible tube is expanded in the area adjacent the inlet.