Moving captive seal construction usable under high temperature and cryogenic conditions

Claim 1

A captive seal construction comprising: an outer member and an inner member, said outer member at least substantially circumscribing said inner member; at least one of said members including first and second sections; means for relatively moving said sections toward each other; said outer and inner members including first and second srufaces, respectively, said first and second surfaces being radially spaced to define a seal groove therebetween; a sealing mass of deformable sealing material in said seal groove; means including at least portions of said first and second surfaces and first and second retainers for defining a substantially completely enclosed seal cavity for said sealing mass, said retainers being axially arranged in said seal groove and on opposite sides of said sealing mass, said retainers being relatively movable in a generally axial direction to reduce the volume of said seal cavity; means for drivingly associating said first retainer with said first section; means for drivingly associating said second retainer with said second section whereby movement of said sections toward each other tends to move said retainers generally axially toward each other to reduce the volume of the seal cavity and to compressively load said sealing mass, said compressive load being sufficient to cause plastic flow of said sealing mass and to cause the sealing mass to substantially fill said seal cavity; resilient means for resiliently urging said first retainer generally axially in a direction to reduce the volume of the seal cavity; and said first retainer having first and second resilient lips engageable with said first and second surfaces of said members, respectively, said lips at least partially defining an axially opening recess opening toward and at least partially receiving said sealing mass.