Patent ID: 7011286

Claim:
A valve for controlling flow of fluid through a conduit, said conduit having an upstream end and a downstream end, said valve comprising: an open-ended sleeve of pliant impermeable material having an upstream end and a downstream end; a clamping device for sealing said upstream end of said sleeve to said downstream end of said conduit; a casing integral with said downstream end of said sleeve, said casing enclosing a drawstring having opposing ends, said downstream end of said sleeve having a bottom portion and a top portion, said bottom portion being longer than said top portion, said ends of said drawstring exiting said casing at said top portion, whereby pulling said ends gathers said downstream end of said sleeve into a closed or partially closed configuration adjacent said top portion; and a resilient stopper attached to said top portion within said sleeve, whereby fully tightening said drawstring ends will bias said casing against said stopper thereby minimizing leaking of fluid from said valve.