Propulsion apparatus for ship

Abstract

Provided is a ship propelling apparatus including a rotation shaft on which a rear propeller is fixed; a front propeller rotatably supported on the rotation shaft in front of the rear propeller; and a counter-rotating device through which the rotation shaft passes, which includes a gear box including therein a plurality of gears configured to reverse rotation of the rotation shaft and transfer the reversed rotation to the front propeller, and which is installed in an installation space formed at the rear of a ship. The rotation shaft includes a measurement hole formed to pass through a center of the rotation shaft for centering of the counter-rotating device installed in the installation space; and an individual lubricant path separated from the measurement hole.

1 . A ship propelling apparatus comprising:
 a rotation shaft on which a rear propeller is fixed;   a front propeller rotatably supported on the rotation shaft in front of the rear propeller; and   a counter-rotating device through which the rotation shaft passes, which includes a gear box including therein a plurality of gears configured to reverse rotation of the rotation shaft and transfer the reversed rotation to the front propeller, and which is installed in an installation space formed at the rear of a ship,   wherein the rotation shaft comprises:   a measurement hole formed to pass through a center of the rotation shaft for centering of the counter-rotating device installed in the installation space; and   an individual lubricant path separated from the measurement hole.   
     
     
         2 . The ship propelling apparatus of  claim 1 , wherein the counter-rotating device comprises:
 a first connector coupled to a drive flange provided on the rotation shaft so as to transfer a rotational force of the rotation shaft to the plurality of gears; and   a second connector coupled to a hub of the front propeller to transfer outputs of the plurality of gears to the front propeller.   
     
     
         3 . The ship propelling apparatus of  claim 2 , wherein the plurality of gears comprises:
 a drive bevel gear coupled to the first connector;   a driven bevel gear supported rotatably around the rotation shaft and coupled to the second connector; and   at least one reverse bevel gear configured to reverse rotation of the drive bevel gear and transfer the reversed rotation to the driven bevel gear.   
     
     
         4 . A ship propelling apparatus comprising:
 a rear propeller fixed on a rotation shaft;   a front propeller supported rotatably on the rotation shaft in front of the rear propeller; and   a counter-rotating device configured to reverse rotation of the rotation shaft and transfer the reversed rotation to the front propeller,   wherein the counter-rotating device comprises a gear box including therein a plurality of gears for reversing rotation of the front propeller and accommodated in an installation space formed in a tail of a ship, and   a fixing flange provided at the front of the gear box, and including a separation groove which is a through-groove, wherein the gear box is separated from the installation space by applying a force to the gear box by inserting a bolt into the separation groove.   
     
     
         5 . The ship propelling apparatus of  claim 4 , wherein a plurality of separation grooves are formed along a marginal portion of the fixing flange that is in close contact with the gear box. 
     
     
         6 . The ship propelling apparatus of  claim 5 , further comprising a coupling member which is coupled to the separation groove and into which a clamp bolt is inserted to fix the front of the gear box on the tail of the ship. 
     
     
         7 . The ship propelling apparatus of  claim 6 , wherein the gear box is separated from the installation space due to a force applied to the gear box by the bolt inserted into the separation groove in a state in which the clamp bolt and the coupling member are loosened from the separation groove. 
     
     
         8 . The ship propelling apparatus of  claim 4 , wherein a marginal portion of the fixing flange that is in close contact with the gear box comprises:
 clamp grooves into which clamp bolts are inserted to fix a front cover on the tail of the ship; and   separation grooves formed alternately with the clamp grooves.   
     
     
         9 . The ship propelling apparatus of  claim 8 , wherein the gear box is separated from the installation space due to a force applied to the front cover by the bolts inserted into the separation grooves in a state in which the clamp bolts are loosened from the clamp grooves. 
     
     
         10 . The ship propelling apparatus of  claim 4 , wherein the fixing flange is coupled to the tail of the ship or formed integrally with the tail of the ship. 
     
     
         11 . A ship propelling apparatus comprising:
 a rear propeller fixed on a rotation shaft;   a front propeller supported rotatably on the rotation shaft in front of the rear propeller;   a counter-rotating device including a plurality of gears for revering rotation of the rotation shaft and transferring the reversed rotation to the front propeller, and accommodated in an installation space formed in a tail of a ship; and   a sealing device configured to seal between a hub of the front propeller and a hub of the rear propeller,   wherein the sealing device comprises:   a pressurizing ring member coupled to one of the hubs and configured to apply a pressurizing force to the other hub; and   a support ring member coupled to the other hub, and configured to be in surface contact with the pressurizing ring member in a sliding manner.   
     
     
         12 . The ship propelling apparatus of  claim 11 , wherein the pressurizing ring member comprises:
 a fixing ring coupled to one of the hubs;   a moving ring disposed apart from the fixing ring, and including a pressurizing unit that is in surface contact with the support ring member; and   an elastic unit coupled between the fixing ring and the moving ring, and configured to apply a pressurizing force to pressurize the moving ring toward the support ring member.   
     
     
         13 . The ship propelling apparatus of  claim 12 , wherein the pressurizing unit is coupled to the moving ring to be detachable from the moving ring. 
     
     
         14 . The ship propelling apparatus of  claim 12 , wherein a sliding surface of the pressurizing unit that is in surface contact with the support ring member is perpendicular to the rotation shaft. 
     
     
         15 . The ship propelling apparatus of  claim 12 , wherein the elastic unit comprises:
 a pair of fixing units, both ends of which are coupled to outer surfaces of the fixing ring and the moving ring; and   a circular arc unit configured to connect the pair of fixing units to apply the pressurizing force.   
     
     
         16 . The ship propelling apparatus of  claim 13 , further comprising a sealing unit configured to seal between the moving ring and the pressurizing unit.