Patent ID: 7530997

Claim:
A valve assembly comprising: a support ring having an outer surface and an inner surface; a valve body comprising an annular body portion supporting a plurality of moveable leaflets that are moveable relative to the annular body portion and to each other between a first closed position and at least one second open position defining a first fluid pathway for the flow of fluid in a first direction across the assembly when subject to a first pressure differential across the body; wherein the annular body portion is mountable to the inner surface of the support ring and is relatively rotatable thereto; and further wherein the annular body portion is axially moveable relative to the support ring from a sealed position to at least one unsealed position, the annular body portion and the support ring, in the unsealed position together defining a second fluid pathway for the flow of fluid in said first direction across the assembly and wherein the annular body portion moves to its at least one unsealed position when the assembly is subjected to the first pressure differential.