Patent ID: 7712724

Claim:
A ball valve comprising: a valve body defining a flow passage having a plurality of flow ports and a valve chamber thereinbetween; a valve member disposed within the valve chamber and having a through passage therein defining through passage openings, the valve member selectively movable within the valve chamber between an open position and a closed position, the open position providing an in-fluid-communication alignment of the through passage with a first flow port of the plurality of flow ports and at least another one of the plurality of flow ports, and the closed position providing an out-of-fluid-communication alignment of the through passage with the first flow port for blocking flow between the first port and the through passage; a seal including a seal member carried by the valve body in sealing contact with the first port, the seal member having, in the open position, a first end substantially aligned with a first one of the through passage openings and positioned a first distance from an axis of rotation of the valve member, and in the closed position, the seal member is aligned with and in sealing contact with a seal-off portion of the surface of the valve member and positioned a second distance from the axis of rotation, the second distance being greater than the first distance; and a spring member biasing the dynamic seal member toward the valve member.