Propulsion unit for surface or submarine vessels comprises rotary endless or Archimedes screw in place of propeller screw

摘要

The propulsion unit consists of an endless or Archimedes screw (1) mounted in supporting bearings (5), preferably with a number of such screws on each side of a surface or submarine vessel. The screws can be rotated in either direction to propel the vessel ahead or astern, reduce speed or steer it.