Patent attributes
An expansion ring assembly seals a gasket with respect to an annular wall of a rigid structure. The expansion ring assembly includes two arcuate expansion ring bands that cooperate to define a generally circular profile. At one side of the expansion ring assembly, a first pair of ends of the expansion ring bands overlap and include a ratcheting mechanism which allows the ring to incrementally expand but not to contract. At another location of the expansion ring assembly, a second pair of ends are joined by a drive mechanism for engaging and driving apart the opposing ends of an expansion ring to thereby non-incrementally expand the ring. The ratchet mechanism may be used to initially set and hold the expansion ring against a gasket in a desired position and to provide an initial expansion pressure, i.e., for a coarse adjustment. The drive mechanism may then be used to provide a final expansion pressure of the gasket, i.e., for a fine adjustment. Advantageously, the coarse adjustment followed by the final adjustment allows a user to quickly and precisely achieve a desired gasket pressure by manipulating the torque applied to the drive mechanism.
