Patent ID: 7823885
Filing Date: 2010-11-02
Classification: F16J

Abstract:
1. A dual seal assembly, in particular for sealing a gas compressor, comprising: a first mechanical seal assembly including a pair of co-operating seal rings, one of which is provided for common rotation with a rotating component and the other of which is provided rotationally fixed at a stationary component, a second mechanical seal assembly including a pair of co-operating seal rings, one of which is provided for common rotation with a rotating component and the other of which is provided rotationally fixed at a stationary component, one of the seal rings being axially movable and axially biased with a biasing force against the respectively other seal ring, said biasing force being transmittable through a force transmitting ring to the respective seal ring, in order to bias facing sliding surfaces of the seal rings, between which a sealing gap is formed during operation, in a mutual sealing engagement, and a secondary sealing assembly for sealing the axially movable seal ring with respect to circumferential guiding surfaces of a guiding component guiding the movement of the seal ring and the force transmitting ring, wherein the secondary sealing assembly is provided at the force transmitting ring and consists a pair of annular sealing members made of an elastic material, said sealing members being retained at the force transmitting ring near its periphery and its end face facing the seal ring such that the sealing members protrude beyond the force transmitting ring at least axially and are movable radially beyond the periphery of the end face due to the effect of the biasing force, such that the annular sealing members are configured to sealingly engage simultaneously with the seal ring and the circumferential guiding surfaces, whereas such engagement is substantially prevented when no biasing force is effective, wherein the axially movable seal ring is devoid of any grooves for receiving sealing members, wherein the circumferential guiding surfaces delimit a guiding ring space therebetween, in which the force transmitting ring and at least an axial portion of the seal ring is received, wherein one of the sealing members is retained near the inner periphery and the other of the sealing members is retained near the outer periphery of the force transmitting ring of the end face facing the seal ring, wherein the one sealing member is configured to sealingly engage with one of the circumferential guiding surfaces and the other sealing member is configured to sealingly engage with the other circumferential guiding surface, while the sealing members simultaneously delimit an axial gap space region circumferentially at the end face, wherein the first mechanical seal assembly and the second mechanical seal assembly are arranged back-to-back.