Patent ID: 7721973

Claim:
A valve for use with a fluid, said valve comprising: a valve body having: a pair of spaced-apart flow ports; an interior chamber; an interior wall at least partially dividing the interior chamber into a first subchamber to which one of the flow port leads and a second subchamber to which the other of the flow ports leads, the interior wall having a wall opening therethrough leading between the first subchamber and the second subchamber; an interior opening providing for communication between the first subchamber and the second subchamber; and a further flow port spaced-apart from the interior opening along an axis; and a plug having a plug opening therein, the plug being axially moveable in the interior chamber between and a first position and a second position, wherein at the second position, the plug seals the further flow port and the valve defines: a first flow path between the spaced-apart flow ports, through the wall opening; and a second flow path between the spaced-apart flow ports, through the interior opening and the plug opening, and at the first position, the interior wall seals the plug opening and the plug seals the interior opening and the wall opening, thereby to at least substantially isolate the first subchamber from the second subchamber and to channel the flow through a further flow path for said fluid through the valve body between the other of the flow ports and the further flow port.