Patent ID: 7896187
Filing Date: 2011-03-01
Classification: F16J,Y10T

Abstract:
1. A closure for an opening in a pipe, vessel, or hub extending therefrom comprising: a round door having an inner and outer surface; an arcuate expandable locking ring movably retained proximate an outer circumference of said outer surface of said door; said arcuate locking ring being suitable to expand and contract wherein an outer circumferential portion of said locking ring is suitable to engage a groove within an inner circumferential surface of said opening when said locking ring is in an expanded orientation and is suitable to contract to a circumference less than the inner circumference of said opening; and a locking ring actuator having a cylinder with a piston slidably disposed therein, said piston having a piston rod extending axially therefrom with a portion extending beyond said cylinder, said cylinder rotatingly engaging a first point of said arcuate locking ring, said portion of said piston rod extending beyond said cylinder rotatingly engaging a second point of said arcuate locking ring wherein said locking ring actuator moves in relation to radial expansion and contraction of said locking ring.