Patent ID: 6508472
Filing Date: 2003-01-21
Classification: F16L

Abstract:
A multi-channel rotary joint, characterized by comprising:a joint housing; a rotator rotatably linked to said joint housing; a plurality of mechanical seals and at least one elastic seal disposed in a row in an axial direction of said rotator between opposing peripheral surfaces of said joint housing and said rotator; at least one first connecting space sealed by two adjacent mechanical seals of said plurality of mechanical seals of said plurality of mechnical seals and having an annular space formed between said opposing peripheral surfaces, and at least one second connecting space sealed by an elastic seal and a mechanical seal adjacent thereto; and a first fluid passage passing through said first connecting space, and a second fluid passage passing through said second connecting space, wherein said mechanical seals are end-contact type and equipped with: a stationary seal ring fixed to one of said opposing peripheral surfaces, a movable seal ring held axially slidable by another of said opposing peripheral surfaces, and a spring member that biases said movable seal ring to press against said stationary seal ring, said mechanical seals being of balanced types in which a balance ratio &kgr; is 0&lE;&kgr;&lE;1, and said elastic seal is equipped with: an annular main body and cylindrical inner and outer peripheral lips that protrude axially from said annular main body and are in elastically pressing contact with said opposing peripheral surfaces, said elastic seal being engaged and fixed to one of said opposing peripheral surfaces in a state in which an annular groove between inner and outer peripheral lips opens into said second connecting space having a higher pressure than an adjacent space that is divided there from by said elastic seal.