Drive mechanism for a fluke drive and method for installning the same

Abstract

A drive mechanism and a method for installing a drive mechanism for a fluke drive. The drive mechanism converts rotary movement into pivoting movement, and includes a first part, a second part having second-part engagement means, a third part having third-part engagement means; and a rod part having a first and a second end. The second part is rotatable in relation to the first part along a rotary axis which is common to the first part and the second part. The third part is reciprocatingly pivotable in relation to the first part about a first pivot axis which is not the same as the rotary axis. The first pivot axis is fixed in relation to the first part. The second-part engagement means is arranged eccentrically with respect to the rotary axis. The first end engages with the second-part engagement means. The second end engages with the third-part engagement means.

1 . A drive mechanism for a fluke drive, the drive mechanism being arranged to convert a rotary movement into a pivoting movement, the drive mechanism, comprising:
 a first part;   a second part comprising a second-part engagement means;   a third part comprising a third-part engagement means; and   a rod part comprising a first end and a second end,   wherein the second part is rotatable in relation to the first part along a rotary axis that is common to the first part and the second part,   wherein the third part is reciprocatingly pivotable in relation to the first part about a first pivot axis that is not parallel to the rotary axis,   wherein the first pivot axis is fixed in relation to the first part,   wherein the second-part engagement means is arranged eccentrically with respect to the rotary axis,   wherein the first end engages with the second-part engagement means,   wherein the second end engages with the third-part engagement means, and   wherein the third-part engagement means is pivotally connected to the second end so that the second end can pivot in relation to the third part about a second pivot axis, the second pivot axis being perpendicular to the first pivot axis.   
     
     
         2 . The drive mechanism of  claim 1 , wherein:
 the first part is fixed to the hull of a vessel.   
     
     
         3 . The drive mechanism of  claim 2 , wherein:
 the first part is pivotable in relation to the hull of the vessel about the rotary axis.   
     
     
         4 . The drive mechanism of  claim 1 , wherein:
 the rotary axis is a main axial direction of a propeller axle of a vessel.   
     
     
         5 . The drive mechanism of  claim 1 , wherein:
 the rotary axis is the main axial direction of a drive axle being connected via a coupling to a propeller axle of a vessel.   
     
     
         6 . The drive mechanism of  claim 4 , wherein:
 the second part is directly or indirectly connected to the propeller axle so that the second part rotates with the propeller axle.   
     
     
         7 . The drive mechanism of  claim 1 , wherein:
 the third part is pivotally connected to the first part, allowing the third part to pivot in relation to the first part about the first pivot axis.   
     
     
         8 . The drive mechanism of  claim 1 , wherein:
 the second-part engagement means comprises a socket for receiving the first end, the socket having a main longitudinal direction which is slanted in relation to the rotary axis.   
     
     
         9 . The drive mechanism of  claim 1 , wherein:
 the third-part engagement means is pivotally connected to the second end via a second rotary bearing.   
     
     
         10 . The drive mechanism of  claim 1 , wherein:
 the rod part has a main direction of elongation being set at an angle in relation to the rotary axis of at least 8 degrees.   
     
     
         11 . The drive mechanism of  claim 10 , wherein:
 the rod part has a main direction of elongation being set at an angle in relation to the rotary axis of between 10 and 60 degrees.   
     
     
         12 . The drive mechanism of  claim 1 , wherein:
 the third part is connected to a fluke.   
     
     
         13 . The drive mechanism of  claim 12 , wherein:
 the third part is connected to the fluke via a flexible element comprising a flexible material body, allowing the fluke to pivot in relation to the fluke rod due to the resilience of the flexible material body.   
     
     
         14 . The drive mechanism of  claim 13 , wherein:
 the flexible material body is dimensioned so that a plane of the fluke is parallel to the rotary axis, within +/−10 degrees, when the fluke is driven in water and when the fluke rod is at its maximum/minimum full amplitude pivot position during use at a set cruise operation rotary speed of the rotary axis.   
     
     
         15 . A method for installing the drive mechanism of  claim 1 , the method comprising:
 providing a vessel having a propeller axle; and   mounting the first part to a hull of the vessel and the second part to the propeller axle.   
     
     
         16 . The method of  claim 15 , further comprising:
 selecting a flexible material body interconnecting a fluke rod to a fluke of the drive mechanism, the flexible material body being selected with resilient properties so that a main plane of the fluke is parallel to the rotary axis when the fluke is driven in water and when the fluke rod is at its maximum/minimum full amplitude pivot position during use at a set cruise operation rotary speed of the propeller axle.   
     
     
         17 . The method of  claim 15 , wherein:
 the first part is mounted on the hull so that a fluke rod of the drive mechanism pivots in a vertical plane.   
     
     
         18 . The method of  claim 15 , further comprising:
 mounting two drive mechanisms according to  claim 1  in parallel; and   mounting the respective first part on the hull so that a respective fluke rod of the respective drive mechanism pivots in non-parallel planes or counter-pivots in a common pivot plane.   
     
     
         19 . The method of  claim 15 , further comprising:
 connecting the second part to a pivotable drive axle being connected via a coupling to the propeller axle; and   providing the first part with a steering mechanism, arranged to pivot the pivotable drive axle in a horizontal plane.   
     
     
         20 . The method of  claim 15 , wherein:
 the installing of the drive mechanism is a retrofitting of the drive mechanism, wherein the vessel is an already-existing vessel and the propeller axle is an already-existing propeller axle of the vessel, and wherein the method further comprises:   installing the drive mechanism onto the propeller axle.