Patent ID: 8430630
Filing Date: 2013-04-30
Classification: B64C,B64D,F16J

Abstract:
1. A rotary coupling comprising: a first element and a coaxial second element, the first and second elements being rotatable relative to each other and defining an annular passage between radially facing walls thereof, a sealing ring at an end of the annular passage, the sealing ring being mounted to the wall of the first element and rotating relative to the second element, the sealing ring having (1) an active configuration in which the sealing ring is urged against the wall of the second element to seal the end of the annular passage, and (2) a return configuration in which the sealing ring does not seal the end of the annular passage, both the first element and the sealing ring being rotatable relative to the second element when the sealing ring is in both the active configuration and the return configuration, and a control system for applying a variable load to the sealing ring, wherein the sealing ring moves between the active and return configurations in response to variation in the applied load.