Marine propulsion device

Abstract

A marine propulsion device includes: a propeller; a first power source for rotating the propeller, a second power source for rotating the propeller; a propeller shaft provided with the propeller; a first drive shaft connected to the first power source; a second drive shaft connected to the second power source; a transmission shaft connected to the propeller shaft; and a dog clutch that switches a connection mode of the first drive shaft, the second drive shaft, and the transmission shaft between at least two of: a first mode in which the first drive shaft and the transmission shaft are connected to each other; a second mode in which the second drive shaft and the transmission shaft are connected to each other; and a third mode in which both the first drive shaft and the second drive shaft are connected to the transmission shaft.

1 . A marine propulsion device comprising:
 a propeller;   a first power source for rotating the propeller;   a second power source for rotating the propeller;   a propeller shaft provided with the propeller;   a first drive shaft connected to the first power source;   a second drive shaft connected to the second power source;   a transmission shaft connected to the propeller shaft; and   a dog clutch that switches a connection mode of the first drive shaft, the second drive shaft, and the transmission shaft between at least two of: a first mode in which the first drive shaft and the transmission shaft are connected to each other; a second mode in which the second drive shaft and the transmission shaft are connected to each other; and a third mode in which both the first drive shaft and the second drive shaft are connected to the transmission shaft.   
     
     
         2 . The marine propulsion device according to  claim 1 , wherein
 the first drive shaft and the transmission shaft each extend in a vertical direction and the transmission shaft is disposed below the first drive shaft coaxially with the first drive shaft,   the dog clutch is provided in an upper end of the transmission shaft to not be rotatable relative to the transmission shaft and to be movable in the vertical direction relative to the transmission shaft, and   the first drive shaft and the dog clutch engage with each other when the dog clutch moves upward so that rotation of the first drive shaft is transmitted to the transmission shaft, and the first drive shaft and the dog clutch disengage from each other when the dog clutch moves downward so that the rotation of the first drive shaft is no longer transmitted to the transmission shaft.   
     
     
         3 . The marine propulsion device according to  claim 2 , further comprising:
 a first gear and a second gear, wherein   the second drive shaft extends in a direction perpendicular to the vertical direction,   the first gear is provided on an outer circumferential side of the transmission shaft and below the dog clutch to be rotatable relative to the transmission shaft,   the second gear is provided in an end of the second drive shaft to not be rotatable relative to the second drive shaft and to transmit rotation of the second drive shaft to the first gear, and   the first gear and the dog clutch engage with each other when the dog clutch moves downward so that the rotation of the second drive shaft is transmitted to the transmission shaft, and the first gear and the dog clutch disengage from each other when the dog clutch moves upward so that the rotation of the second drive shaft is no longer transmitted to the transmission shaft.   
     
     
         4 . The marine propulsion device according to  claim 3 , further comprising:
 a one-way clutch, wherein   the one-way clutch is provided between the first gear and the transmission shaft,   the dog clutch switches a connection mode of the first drive shaft, the second drive shaft, and the transmission shaft between the first mode and the second mode, and   when the dog clutch moves upward to separate the first gear and the dog clutch from each other and a rotation speed of the first gear in a predetermined direction is higher than a rotation speed of the transmission shaft in the predetermined direction, the rotation of the second drive shaft is transmitted to the transmission shaft by the one-way clutch.   
     
     
         5 . The marine propulsion device according to  claim 3 , wherein an engaging portion is provided in an inner circumferential portion of an upper part of the first gear and engages with the dog clutch when the dog clutch moves downward. 
     
     
         6 . The marine propulsion device according to  claim 4 , further comprising:
 a clutch shaft, wherein   the clutch shaft extends in the vertical direction and is provided in an upper end of the transmission shaft to be coaxial with the transmission shaft and to not be rotatable relative to the transmission shaft,   the dog clutch is provided in the clutch shaft to not be rotatable relative to the clutch shaft and to be movable in the vertical direction relative to the clutch shaft,   the first gear is provided on an outer circumferential side of the clutch shaft and below the dog clutch to be rotatable relative to the clutch shaft, and   the one-way clutch is disposed between a boss of the first gear and the clutch shaft.   
     
     
         7 . The marine propulsion device according to  claim 3 , further comprising:
 a control device that controls movement of the dog clutch, wherein   the second drive shaft extends in a front-rear direction, and   the control device is disposed on a left side or a right side of the dog clutch.