Patent ID: 6406261
Filing Date: 2002-06-18
Classification: B63H,B64C,B64D,F16H

Abstract:
A counter propeller propulsion unit comprising:a prime mover; a drive shaft connected to and rotatable by said prime mover; a power pulley secured to said drive shaft so as to be rotatable in a forward rotation direction by said prime mover; a supporting body; a main shaft having first and second ends, wherein said first end is rotatably supported by said supporting body; a reverse pulley secured to said main shaft; a forward pulley rotatably fitted to said main shaft and said reverse pulley via bearings; a forward propeller connected to said forward pulley; a flange secured to said main shaft at or near said second end of said main shaft; a counter propeller secured to said flange; a forward-running belt contacting said forward pulley and said power pulley so as to interlock said forward pulley and said power pulley, such that said forward pulley and said forward propeller are rotatable in a forward rotation direction by said forward-running belt and said power pulley; a tension pulley; a reverse-running belt contacting said reverse pulley and said tension pulley on an inside of said reverse-running belt, and contacting said power pulley on an outside of said reverse-running belt so as to interlock said reverse pulley and said power pulley such that said reverse pulley, said main shaft, said flange, and said counter propeller are rotatable in a counter rotation direction that is opposite to the forward rotation direction, wherein said forward propeller and said counter propeller are rotated in opposite directions.