Drain with captive vandal-proof stopper

Claim 1

A captive, pop-up fluid flow control device, said device being non-removable from the drain opening adjacent to the fluid containment side of the fluid container, which comprises: a body having a drain passageway therethrough and an inlet end and an outlet end; a rim formed as an integral part of the body and disposed within the drain passageway near the inlet opening thereto and projecting inwardly towards the center thereof; thereby forming a fluid shut-off seat; means for connecting the inlet end of the body to the drain opening in said fluid container; a stopper having a central stem and a top and a lower portion, wherein the top portion is engageable with the seat and the lower portion being operable within the body and having a transverse passageway therethrough; means for spacing and guiding the lower portion of the stopper within the body and the drain opening in such a manner as to allow fluid communication between the drain opening and the fluid container; means for raising and lowering the stopper to move the top towards and away from the seat; a locking means adapted to be disposed within the transverse passageway, whose length is greater than the diameter of the opening in the rim wherein the enDs of the locking pin are disposed beneath said rim and maintained therebeneath by the guiding and spacing means whereby the complete withdrawal of the lower portion of the stopper from the drain inlet is prevented; and means within the body for passing the locking pin therethrough whereby the locking pin may be installed in the transverse passageway; and means for supporting the ends of the locking pin disposed in the transverse passageway whereby said stopper may be maintained and disengaged from the seat after the top of the stopper is moved away from the seat, thereby placing the drain opening in fluid communication with the drain passageway.