Patent ID: 6425583
Filing Date: 2002-07-30
Classification: F16J

Abstract:
A mechanical seal comprising:a rotary shaft; a rotary ring having a plate shape and axis attached via a centering element to the rotary shaft so as to rotate together with the rotary shaft, the rotary ring having a seal end face at a first end of the rotary ring and an opposite end face at a second end of the rotary ring, wherein both of the seal end face and the opposite end face extend in a direction orthogonal to the axis of the rotary shaft; a buoyancy generating means formed on the seal end face of the rotary ring; a fixed body which the rotary shaft rotates relative to; a stationary ring axially movable and rotationally fixed to the fixed body and having a seal end face in a direction orthogonal to the axis of the rotary shaft at a first end of the stationary ring, wherein the seal end face of the rotary ring rotates relative to the seal end face of the stationary ring via a subject to be sealed therebetween so as to constitute a non-contact mechanical seal; and an energizing means for pressing the stationary ring toward the rotary ring along the axis of the rotary shaft, the rotary ring being made of a metal, the rotary ring having such a sectional shape that a location of a center of gravity of the rotary ring is set at a position dislocated from a center line of a plate thickness of the rotary ring in a direction of the axis toward the opposite end face of the rotary ring, wherein the rotary ring is not substantially deformed due to centrifugal force when it rotates at a first stage high speed, and the rotary ring is deformed mainly due to heat and centrifugal force at a second stage high speed and the deformation of the rotary ring due to heat is cancelled by the deformation of the rotary ring due to centrifugal force.