Sail-drive propulsion system for boats

Abstract

A boat propulsion including a drive motor coupled to a sail-drive transmission equipped with a drive shank carrying a propeller shaft for a propeller, and a supporting and sealing flange, to which said drive shank is attached, wherein said supporting and sealing flange has an upper and a lower side and consists of a main portion, to which said drive shank is attached, and at least an extension portion provided with at least one through opening into which a corresponding nozzle is engaged with an ejection section, arranged on the underside of said flange, with an exit channel having an axis oriented substantially horizontally so as to produce a thrust in a different direction from that produced by said propeller, an inlet section, located on the upper side of said flange, connected to a pressurized water supply pipe from at least a pressurization pump connected to a water loading inlet.

What is claimed is: 
     
         1 . A boat propulsion system equipped with sail-drive transmission comprising
 a drive motor (M) coupled to a sail-drive transmission equipped with a drive shank ( 1 ) carrying a propeller shaft ( 3 ) for a propeller at a distal end, and   a supporting and sealing flange ( 2 ), apt to be engaged in a correspondingly shaped opening of a boat's hull, to which said drive shank ( 1 ) is attached,   
       wherein
 said supporting and sealing flange ( 2 ) has an upper and a lower side and consists of a main portion ( 2   a ), to which said drive shank ( 1 ) is attached, and at least an extension portion ( 2   b ) provided with at least one through opening ( 6   a ,  6   b ) into which a corresponding nozzle ( 8 ) is engaged, which nozzle is provided with
 an ejection section ( 8   b ), arranged on the underside of said flange ( 2 ), with an exit channel having an axis oriented substantially horizontally so as to produce a thrust in a different direction from that produced by said propeller, 
 an inlet section ( 8   a ), located on the upper side of said flange ( 2 ), connected to a pressurized water supply pipe from at least a pressurization pump ( 9 ) connected to a water loading inlet. 
 
 
     
     
         2 . The boat propulsion system as in  claim 1 , wherein said extension portion ( 2   b ) is provided with a pair of through openings ( 6   a ,  6   b ) into which are engaged corresponding nozzles ( 8   a ,  8   b ) with ejection sections ( 8   b ) oriented in directions having at least opposed components. 
     
     
         3 . The boat propulsion system as in  claim 2 , wherein a single pressurization pump ( 9 ) which supplies pressurized water alternately to said nozzles ( 8   a ,  8   b ) by means of a three-way valve ( 10 ) controlled by means of a logic control unit is provided. 
     
     
         4 . The boat propulsion system as in  claims 2 , wherein one of said nozzles ( 8   a ,  8   b ) alternately serves as said water loading inlet. 
     
     
         5 . The boat propulsion system as in  claim 1 , wherein said drive motor (M) has a power take-off to which said pressurization pump ( 9 ) is coupled. 
     
     
         6 . The boat propulsion system as in  claim 1 , wherein said drive motor (M) is an electric motor. 
     
     
         7 . The boat propulsion system as in  claim 1 , wherein sealing means are provided on said lower side of said flange ( 2 ). 
     
     
         8 . The boat propulsion system as in  claim 7 , wherein said sealing means consist of two separate seals (G 1 , G 2 ) on said main portion ( 2   a ) to circumscribe a longitudinal axis of said drive shank ( 1 ) and on said extension portion ( 2   b ) to circumscribe said openings ( 6   a ,  6   b ), respectively.