Fluid coupling

Abstract

A fluid coupling has a first part (100) sealed to a sealing surface of a second part (200), wherein the first part carries a sealing part (300) and the second part includes a gap (G) in the sealing surface, across which the sealing part is arranged to transition. A vent (210) is provided between the sealing surface and the gap. An aperture to the vent on the sealing surface is relatively small so that fluid pressure does not act to deform the seal as it crosses said aperture. Said aperture is spaced off-set from the gap on the sealing surface. The off-set provides a portion of sealing surface adjacent the gap and between the gap and aperture against which the seal can contact. The vent acts to allow fluid (400) to enter the gap before the seal starts to cross the gap and to therefore act to equalise pressure on either side of the seal. Consequently, as the seal transitions across the gap and the sealing between two parts is lost, the fluid pressure imbalance that would otherwise act to deform the seal into the gap has been reduced. The risk of seal damage during the transition has also therefore been reduced.

Dependencies are inferred from the claim text.