Patent ID: 6769698
Filing Date: 2004-08-03
Classification: F16J,F16L

Abstract:
A fluid seal structure sealing between a tank made of composite material including resin material, the tank including a fluid contained therein, and a cover covering an opening of the tank, comprising:a ring groove formed at a joint between adjoining faces of first and second joint members of the tank and cover, at least one of said first and second joint members being made from said resin material; and a seal ring which fits into said ring groove so as to provide a tight seal to contain fluids, said seal ring having a heart-shaped sectional shape and a hollow cavity and being made from resilient material having a greater low temperature contraction rate than that of said resin material; wherein said ring groove is provided in said first joint member; wherein said seal ring comprises: a first curved seal surface which makes contact with a bottom surface of said ring groove in said first joint member, a second curved seal surface which makes contact with said second joint member, first and second resilient curved surfaces which respectively curve from said first and second curved seal surfaces towards the inside of said hollow cavity and said heart-shaped sectional shape so as to provide an indent that forms the heart-shaped sectional shape, and a pair of opposing end surfaces respectively extending from said first and second resilient curved surfaces so as to form a gap between said pair of opposing end surfaces; wherein an outer circumference of said first and second resilient curved surfaces is structured so as to maintain contact with an inner side wall of said ring groove during low temperature contraction; and wherein a seal between the tank and cover is achieved by the cover covering the opening of the tank to seal the fluid in the tank from the outside with said first curved seal surface contacting with said bottom surface of said ring groove, said ring groove being provided in a sealing surface of the tank, and with said second curved seal surface contacting with a sealing surface of the cover facing the opening of the tank.