US Patent 6860437 Jet barrel for a spa jet

A jet barrel adapted for use in a spa jet housing having a rotor rotatably supported on a spindle pin aligned along a longitudinal axis in the bore of the jet barrel. The spindle pin is supported at upstream and downstream pivot points. An offset nozzle extends from a conical base of the rotor, an inlet to the rotor being aligned with an outlet from the jet barrel's bore. As water exits the jet barrel bore into the rotor, the rotor and spindle pin are caused to co-rotate. Hard water deposits, sufficient to prevent rotation do not readily build around the pivot points.