Propulsion device for proximity twin-screw vessel having shaft bracket and ship

Abstract

A propulsion device for a ship includes a port propeller and a starboard propeller, a rudder disposed at a center in a vessel widthwise direction, and shaft brackets installed in front of the port propeller and the starboard propeller, respectively, and configured to rotatably support propeller shafts of the port propeller and the starboard propeller, wherein a distance between a front end of a propeller blade of the port propeller and a front end of a propeller blade of the starboard propeller at the center in the vessel widthwise direction is larger than 0 m and equal to or less than 1.0 m, and a rotational direction of the port propeller and the starboard propeller becomes an outer track rotating outward from the center in the vessel widthwise direction over the port propeller and the starboard propeller.

1 . A propulsion device for a proximity twin-screw vessel having a shaft bracket, the propulsion device comprising:
 a port propeller and a starboard propeller installed at a stern hull;   one rudder disposed at a center in a vessel widthwise direction of the stern hull or two rudders constituted by a port rudder and a starboard rudder in rear of the port propeller and the starboard propeller; and   shaft brackets installed in front of the port propeller and the starboard propeller, respectively, and configured to rotatably support propeller shafts of the port propeller and the starboard propeller,   wherein a distance between a tip end of a propeller blade of the port propeller and a tip end of a propeller blade of the starboard propeller at a center in the vessel widthwise direction is larger than 0 m and equal to or smaller than 1.0 m, and   a rotational direction of the port propeller and the starboard propeller becomes an outer track rotating from the center in the vessel widthwise direction toward the outside over the port propeller and the starboard propeller.   
     
     
         2 . The propulsion device for the proximity twin-screw vessel having the shaft bracket according to  claim 1 , wherein, provided that propeller diameters of the port propeller and the starboard propeller are Dp, a distance between a central position of the port propeller and the starboard propeller and a front edge of the rudder at a central height of the port propeller and the starboard propeller is equal to or less than 1.0 Dp. 
     
     
         3 . The propulsion device for the proximity twin-screw vessel having the shaft bracket according to  claim 1 , wherein the stern hull is a stern structure of a single screw vessel type. 
     
     
         4 . The propulsion device for the proximity twin-screw vessel having the shaft bracket according to  claim 1 , wherein the shaft bracket comprises a shaft support section configured to rotatably support the propeller shafts of the port propeller and the starboard propeller, and a strut configured to connect the shaft support section and the stern hull, and
 the strut is formed to provide flows in an opposite direction of a rotational direction of the port propeller and the starboard propeller in upper sections of the port propeller and the starboard propeller.   
     
     
         5 . The propulsion device of the proximity twin-screw vessel having the shaft bracket according to  claim 1 , wherein the shaft bracket comprises a shaft support section configured to rotatably support the propeller shafts of the port propeller and the starboard propeller, and a strut configured to connect the shaft support section and the stern hull, and
 the shaft support section comprises one or more fins radially extending from an outer circumferential section of a lower section thereof, and each of the fins is formed to provide flows in an opposite direction of a rotational direction of the port propeller and the starboard propeller in lower sections of the port propeller and the starboard propeller.   
     
     
         6 . A ship comprising the propulsion device of the proximity twin-screw vessel having the shaft bracket according to  claim 1 .