Water jet propulsion system

摘要

A water jet propulsion system for watercraft having an impeller, especially a conical oblique flow impeller with an increased outer diameter in going toward the downstream side. The impeller is secured to a transmission shaft which is journalled by bearings in a hub of fixed blades and formed at its end portion with spline grooves being able to fit in spline strips formed at the forward end portion of a drive shaft. This allows a pump portion of the water jet propulsion system to be assembled outside the watercraft and separately therefrom, so that positioning of the impeller with respect to its duct can be effected with a high degree of accuracy.