Patent ID: 6234852
Filing Date: 2001-05-22
Classification: B63H

Abstract:
An impeller for a water jet pump of a watercraft having separate and coaxial propeller and pump shafts, the impeller having an upstream portion configured to be fixed to the propeller shaft which is connected to an engine of said watercraft and has a spline shaft portion at a free end thereof, and a downstream portion configured to be fixed to the pump shaft which is mounted for rotation in a pump casing of said watercraft and has a threaded free end thereof having screw threads, said impeller comprising:a tip portion defining a spline hole formed directly in the tip portion of the impeller configured for coupling to said spline shaft portion of the propeller shaft;a rear end portion defining a fitting hole formed in the rear end portion of the impeller; anda cylindrical member having an outer periphery which is configured to be fitted into the fitting hole, said cylindrical member defining a female screw hole having screw threads on an inner peripheral face configured for coupling to said screw threads of said free end of said pump shaft, whereby said impeller is mounted to and connects said propeller shaft and said pump shaft.