Patent ID: 7673677

Claim:
An apparatus for restricting flow through a well conduit, the apparatus comprising: a housing having a longitudinal bore having an axis and a seat disposed within the bore, the seat comprising a slidable element in sliding engagement with an inner wall surface of the housing, the slidable element having a run-in position and a set position, the seat further comprising an engagement surface for receiving a plug element, and a fixed element secured to the housing, the fixed element being operatively associated with the element; a plug element support member operatively associated with the slidable element and the fixed element, the plug element support member having a retracted position defining a first seat inner diameter and an extended position defining a second seat inner diameter, the first seat inner diameter being greater than the second seat inner diameter, the plug element support member being disposed below the seat; and a return member operatively associated with the slidable element for urging the slidable element toward the run-in position, wherein the plug element support member is in the retracted position when the seat is in the run-in position and the plug element support member is in the extended position when the seat is in the set position, the plug element support member restricting the bore when in the extended position, and wherein the plug element is adapted to be disposed into the bore and landed on the seat engagement surface to restrict fluid flow through the bore and the well conduit and to cause the plug element support member to move from the retracted position to the extended position so that the plug element support member restricts the bore and provides support to the plug element landed on the seat engagement surface.