Electric propulsion machine

Abstract

An electric propulsion machine for propelling a boat. The electric propulsion machine includes a motor provided in an upper portion of the electric propulsion machine, a propeller shaft provided in a lower portion of the electric propulsion machine, a propeller provided in the propeller shaft, a drive shaft extending in an upper-lower direction and configured to transmit rotation of the motor to the propeller shaft, and a first non-positive displacement pump provided in the propeller shaft and configured to supply cooling water to the motor, the cooling water cooling the motor.

What is claimed is: 
     
         1 . An electric propulsion machine for propelling a boat, the electric propulsion machine comprising:
 a motor provided in an upper portion of the electric propulsion machine;   a propeller shaft provided in a lower portion of the electric propulsion machine;   a propeller provided in the propeller shaft;   a drive shaft extending in an upper-lower direction and configured to transmit rotation of the motor to the propeller shaft; and   a first non-positive displacement pump provided in the propeller shaft and configured to supply cooling water to the motor, the cooling water cooling the motor.   
     
     
         2 . The electric propulsion machine according to  claim 1 ,
 wherein the first non-positive displacement pump is provided at a front end side of the propeller shaft.   
     
     
         3 . The electric propulsion machine according to  claim 2 , further comprising:
 a transfer passage configured to transfer the cooling water from the first non-positive displacement pump to the motor,   wherein the transfer passage is provided in front of the drive shaft in the electric propulsion machine.   
     
     
         4 . The electric propulsion machine according to  claim 2 , further comprising:
 a water intake port configured to take in water around the electric propulsion machine into the electric propulsion machine,   wherein the water intake port is provided in front of the propeller shaft, and the first non-positive displacement pump faces the water intake port.   
     
     
         5 . The electric propulsion machine according to  claim 2 ,
 wherein the first non-positive displacement pump includes a pump shaft and an impeller,   the impeller is provided at a front end portion of the pump shaft, and   a rear end portion of the pump shaft is connected to a front end portion of the propeller shaft.   
     
     
         6 . The electric propulsion machine according to  claim 1 , further comprising:
 a second non-positive displacement pump provided between the first non-positive displacement pump and the motor, and configured to transfer cooling water discharged from the first non-positive displacement pump to the motor.