Patent attributes
An isolator seal includes a stator member for placement into the stator of rotating equipment and a rotor member for placement onto a rotary shaft of the rotating equipment. The stator member and the rotor member provide respective adjacent surfaces, while a static shut-off device engages both adjacent surfaces when the rotor member is static and disengages one or more of the surfaces when the rotor member is dynamic. In one embodiment of the invention at least one of the surfaces is inclined to the longitudinal axis at an angle greater or less than 90°. In a further embodiment, the static shut-off device includes a resilient annular sealing member and an auxiliary member, which can move between a first position, when the rotor member is static, at which the auxiliary member compresses the resilient annular member into engagement with both surfaces, and a second position at which the compression on the resilient member is reduced, so that the resilient annular member disengages one or more of the rotor and stator surfaces when the rotor is dynamic.
