Thrust producing drive mechanism for watercrafts

Claim 1

A thrust-producing drive mechanism for driving and controlling of watercrafts, comprising: hull means; means defining a vertically downwardly opening recess in the bottom of said hull means free of obstruction by said hull means; an L-shaped elbow having a vertically oriented first part which has at its lower end an inlet opening for a stream of wAter, said inlet opening being approximately equal to and slightly less than the diameter of said downwardly opening recess and a horizontally oriented second part arranged at the upper end of said first part, said second part extending radially of said first part beyond the radius of said first part and having at its end an outlet opening for a stream of water opening outwardly on a plane above the plane of said inlet opening and in a horizontal discharge direction, said inlet opening being larger than said outlet opening to thereby define a nozzle at said outlet opening and a smooth curved transfer section connected between said first and second parts, said L-shaped elbow being located entirely within the contour of said downwardly opening recess, said plane of said inlet opening being positioned closely above the plane of the bottom of said watercraft; support means for supporting said L-shaped elbow for rotatable movement about a vertical axis parallel to the vertical axis of said first part and drive means for driving said L-shaped elbow for said rotatable movement; means defining at least one propeller mounted for rotation about a vertical axis and drive means therefor, said propeller means being mounted inside and connected to said inlet opening of said L-shaped elbow adjacent said lower end thereof, said propeller means conveying said water through said L-shaped elbow from a vertical suction direction through said smooth curved transfer section to said horizontal discharge direction.