Patent ID: 7278840

Claim:
A compliant viscous seal for a rotatable shaft, comprising: an outer body having a shaft hole for passage therethrough of a rotatable shaft to be sealed by the viscous seal; and a sealing sleeve extending axially in the hole and having an inner surface surrounding the shaft, the inner surface having formed therein a helical groove for preventing leakage of fluid along the shaft when the shaft is rotated within the sealing sleeve; wherein an annular gap is provided between coextensive axial portions of the outer body and sealing sleeve to permit limited pivotal movement of the sealing sleeve relative to the outer body for allowing the sealing sleeve to coaxially align with the shaft when in use, and wherein a flexible resilient annular seal, radially interposed between the sealing sleeve and outer body and retained in an annular groove formed in the sealing sleeve, is provided (i) to seal the annular gap thereby to prevent leakage around the outside of the sealing sleeve, and (ii) to support the sealing sleeve within the outer body while allowing the sealing sleeve to pivot with a gimbal action within the outer body.