Outboard motor and boat propulsion device

Abstract

An outboard motor includes a cooling water flow path including an intake port to take in cooling water from outside the outboard motor and through which cooling water flows, and a water pump including an impeller and a pump shaft to rotate together with the impeller to pump the cooling water into the cooling water flow path. An inlet channel of the cooling water flow path from the intake port to the water pump is located in front of the water pump and extends along a rotation axis of the pump shaft, and an inlet that allows the passage of the cooling water and prevents entry of foreign objects is located inside the inlet channel.

What is claimed is: 
     
         1 . An outboard motor to be mounted on a hull, the outboard motor comprising:
 a cooling water flow path including an intake port to take in cooling water from outside the outboard motor and through which cooling water flows; and   a water pump including an impeller and a pump shaft to rotate together with the impeller to pump the cooling water into the cooling water flow path; wherein   an inlet channel of the cooling water flow path from the intake port to the water pump extends along a rotation axis of the pump shaft in front of the water pump; and   a filter to allow passage of the cooling water and prevent entry of foreign objects is located inside the inlet channel.   
     
     
         2 . The outboard motor according to  claim 1 , further comprising:
 a drive unit;   a drive shaft to be rotationally driven by the drive unit;   a propeller; and   a propeller shaft to rotate together with the propeller; wherein   the drive shaft is rotatable in both a forward direction and a reverse direction opposite to the forward direction; and   the water pump is a non-volumetric pump.   
     
     
         3 . The outboard motor according to  claim 2 , wherein the drive unit is an electric motor to be driven by electric power supplied from a power source. 
     
     
         4 . The outboard motor according to  claim 2 , wherein the water pump is a centrifugal pump. 
     
     
         5 . The outboard motor according to  claim 2 , wherein the water pump is located on the rotation axis of the propeller shaft. 
     
     
         6 . The outboard motor according to  claim 1 , wherein the filter is made of resin. 
     
     
         7 . The outboard motor according to  claim 1 , wherein the filter is made of glass fiber reinforced plastic. 
     
     
         8 . The outboard motor according to  claim 1 , wherein the filter includes:
 a holder including a through hole and fixed inside the inlet channel; and   a filter body inside the through hole to allow the passage of the cooling water and prevent entry of foreign objects; wherein   the holder is made of resin; and   the filter body is made of metal.   
     
     
         9 . A boat propulsion device provided on a hull, the boat propulsion device comprising:
 a cooling water flow path including an intake port to take in cooling water from outside the boat propulsion device and through which cooling water flows; and   a water pump including an impeller and a pump shaft to rotate together with the impeller to pump the cooling water into the cooling water flow path; wherein   a filter to allow passage of the cooling water and prevent entry of foreign objects is located at the intake port; and   the filter is located on a rotation axis of the pump shaft in front of the water pump.   
     
     
         10 . A boat comprising:
 a hull; and   the outboard motor according to  claim 1  attached to a transom at a rear end of the hull.   
     
     
         11 . A boat comprising:
 a hull; and   the boat propulsion device according to claim  9  attached to a transom at a rear end of the hull.