Patent ID: 8714598

Claim:
A hydraulic fluid coupling comprising an inline swivel joint, the coupling comprising: a first coupling portion having a central conduit axis; a second coupling portion co-axially aligned with the first coupling portion and having a coupling face perpendicular to the conduit axis abutting the first coupling portion; a central conduit passing through the first and second coupling portions along the central conduit axis; a dynamic seal between the first and second coupling portions; a first bearing between the first and second coupling portions co-axial with the central conduit axis; a ring shaped piston circumferentially disposed about an exterior of the second coupling portion and axially moveable therealong, the piston comprising a piston driving surface and a bearing engaging face; a fluid receiving chamber bounded by at least the piston driving surface and the second coupling portion; at least a radial conduit through the second coupling portion between the central conduit and the fluid receiving chamber; a second bearing circumferentially disposed about an exterior of the second coupling portion and co-axial with the central conduit axis, the second bearing engageable by the piston and supporting rotational and axial movement of the second coupling portion; and, a retaining cap secured to the first coupling portion and extending over the second coupling portion, the second bearing and the piston located between the retaining cap and the second coupling portion, wherein pressurized hydraulic fluid is able to pass through the coupling portions, through the radial conduit and into the fluid receiving chamber to create fluid pressure in the receiving chamber.