Propeller drive arrangement

Abstract

A propeller drive arrangement includes a propeller shaft, a planetary gear comprising a first planetary gear member, a second planetary gear member and a third planetary gear member which are drivingly connected, and an outer shaft arranged coaxially with and radially outside of the propeller shaft. The outer shaft is drivingly connected to one or more propeller blades for varying the pitch angle, and the propeller shaft is drivingly fixed to one of the planetary gear members and another one of the planetary gear members is arranged to drive the outer shaft by a driving torque exerted on the propeller shaft. The propeller drive arrangement has a pitch controlling member for varying the pitch angle of the one or more propeller blades, in a first state, to rotationally fix the third planetary gear member to the second planetary gear member so that the propeller shaft and the outer shaft are arranged to rotate with the same rotational speed, and, in a second state, to engage the third planetary gear member to a housing so that the third planetary gear member is rotationally fixed with respect to the housing.

1 . A propeller drive arrangement, comprising:
 a propeller shaft,   a propeller hub comprising one or more propeller blades, wherein a pitch angle of the one or more propeller blades is variable,   a planetary gear comprising a first planetary gear member, a second planetary gear member and a third planetary gear member which are drivingly connected, and   an outer shaft arranged coaxially with and radially outside of the propeller shaft,   
       wherein the outer shaft is drivingly connected to the one or more propeller blades for varying the pitch angle, 
       wherein the propeller shaft, in one end thereof, is configured to be drivingly connected to a propulsion unit and, in a second end thereof, is drivingly fixed to the propeller hub, and wherein the propeller shaft is drivingly fixed to one of the planetary gear members and wherein another one of the planetary gear members is arranged to drive the outer shaft by a driving torque exerted on the propeller shaft, and
 the propeller drive arrangement further comprising a pitch controlling member for varying the pitch angle of the one or more propeller blades, 
 
       wherein the pitch controlling member is arranged to, in a first state, rotationally fix the third planetary gear member to the second planetary gear member so that the propeller shaft and the outer shaft are arranged to rotate with the same rotational speed, and, in a second state, engage the third planetary gear member to a housing so that the third planetary gear member is rotationally fixed with respect to the housing. 
     
     
         2 . The propeller drive arrangement according to  claim 1 , wherein the first planetary gear member is a sun gear of the planetary gear. 
     
     
         3 . The propeller drive arrangement according to  claim 1 , wherein the second planetary gear member is a planet gear carrier of the planetary gear carrying a plurality of planetary gear wheels. 
     
     
         4 . The propeller drive arrangement according to  claim 1 , wherein the third planetary gear member is a ring gear of the planetary gear. 
     
     
         5 . The propeller drive arrangement according to  claim 1 , wherein the third planetary gear member is a planet carrier of the planetary gear carrying a plurality of planetary gear wheels. 
     
     
         6 . The propeller drive arrangement according to  claim 5 , wherein the second planetary gear member is a sun gear of the planetary gear. 
     
     
         7 . The propeller drive arrangement according to  claim 6 , wherein the first planetary gear member is a ring gear of the planetary gear. 
     
     
         8 . The propeller drive arrangement according to  claim 1 , wherein the pitch controlling member is a clutch member. 
     
     
         9 . The propeller drive arrangement according to  claim 8 , wherein the clutch member is movable between the first state and the second state in any direction corresponding to a direction of a rotational axis of the propeller shaft. 
     
     
         10 . The propeller drive arrangement according to  claim 1 , wherein the outer shaft is arranged to rotate one full revolution or more than one full revolution with respect to the propeller shaft. 
     
     
         11 . The propeller drive arrangement according to  claim 1 , further comprising a first sensor for measuring rotational speed of the outer shaft and/or a second sensor for measuring rotational speed of the propeller shaft. 
     
     
         12 . The propeller drive arrangement according to  claim 11 , further comprising a control unit arranged to receive signals from the first and second sensors which are indicative of rotational speeds of the propeller shaft and the outer shaft, wherein the control unit is configured to output a signal, based on the received signals from the sensors, which is indicative of a current pitch angle. 
     
     
         13 . The propeller drive arrangement according to  claim 1 , further comprising a bevel gear arrangement drivingly connecting the outer shaft with the one or more propeller blades. 
     
     
         14 . The propeller drive arrangement according to  claim 1 , wherein the propeller drive arrangement comprises only one planetary gear. 
     
     
         15 . A vessel comprising a propeller drive arrangement according to  claim 1 .