Personal watercraft

Abstract

A personal watercraft propelled by a jet stream includes a boat body, a jet pump, a tunnel, a tunnel opening and a thrust propulsion device. The jet pump includes an impeller disposed at a rear portion of the boat body and generates a propulsive force, and an impeller shaft that rotates the impeller. The tunnel extends in the boat body. The tunnel opening is located at one end of the tunnel, disposed in front of the jet pump, directed in a thrust direction, and opened in the boat body at a position equal to or lower than a virtual plane extending in a horizontal direction along a rotation axis of the impeller. The thrust propulsion device generates a propulsive force in the thrust direction by causing a fluid to flow from an inside of the tunnel to an outside of the boat body through the tunnel opening.

1 . A personal watercraft propelled by a jet stream, the personal watercraft comprising:
 a boat body;   a jet pump including an impeller that is disposed at a rear portion of the boat body and generates a propulsive force, and an impeller shaft that rotates the impeller;   a tunnel extending in the boat body;   a tunnel opening located at one end of the tunnel, disposed in front of the jet pump, directed in a thrust direction intersecting a front-rear direction of the boat body, and opened in the boat body at a position equal to or lower than a virtual plane extending in a horizontal direction along a rotation axis of the impeller; and   a thrust propulsion device that generates a propulsive force in the thrust direction by causing a fluid to flow from an inside of the tunnel to an outside of the boat body through the tunnel opening.   
     
     
         2 . The personal watercraft according to  claim 1 , wherein
 the tunnel extends linearly in a direction orthogonal to a front-rear direction of the boat body and a vertical direction of the boat body,   the tunnel opening is opened in the boat body at both ends of the tunnel, and   the thrust propulsion device includes a propeller disposed in the tunnel and rotating in the tunnel.   
     
     
         3 . The personal watercraft according to  claim 1 , wherein
 the tunnel and the tunnel opening are disposed at positions overlapping an extension line of a rotation axis of the impeller in a side view of the boat body.   
     
     
         4 . The personal watercraft according to  claim 1 , wherein
 the tunnel opening is disposed in front of a center of gravity of the boat body.   
     
     
         5 . The personal watercraft according to  claim 1 , wherein
 the tunnel opening is opened at a position above a water surface when the personal watercraft is planing.   
     
     
         6 . The personal watercraft according to  claim 1 , further comprising:
 a drive source that is disposed in the boat body and applies a rotational driving force to the impeller shaft; and   an energy storage body that is disposed in the boat body and stores energy supplied to the drive source, wherein   the tunnel is disposed in front of the drive source or the energy storage body.   
     
     
         7 . The personal watercraft according to  claim 1 , wherein
 the thrust propulsion device includes an electric motor for obtaining the propulsive force in the thrust direction and a battery that supplies driving power to the electric motor, and   at least one of the electric motor and the battery is attached to an upper surface of the tunnel.   
     
     
         8 . The personal watercraft according to  claim 1 , wherein
 the thrust propulsion device includes an electric motor for obtaining the propulsive force in the thrust direction and a battery that supplies driving electric power to the electric motor, and   at least one of the electric motor and the battery is attached to a tunnel wall forming the tunnel.   
     
     
         9 . The personal watercraft according to  claim 1 , wherein
 the thrust propulsion device includes one or a plurality of electric motors for obtaining the propulsive force in the thrust direction and one or a plurality of batteries for supplying driving power to the one or the plurality of electric motors, and   the one or the plurality of electric motors and the one or the plurality of batteries are disposed above the tunnel and side by side along an axial direction of the tunnel.   
     
     
         10 . The personal watercraft according to  claim 1 , wherein
 the thrust propulsion device includes:   a propeller that is disposed in the tunnel and rotates around a tunnel axis;   an electric motor having a rotation axis in a direction intersecting the tunnel axis; and   a power transmission portion that converts a rotational force around the rotation axis output by the electric motor into a rotational force around the tunnel axis and transmits the rotational force to the propeller.   
     
     
         11 . The personal watercraft according to  claim 2 , wherein
 the thrust propulsion device includes an electric motor that rotationally drives the propeller, and   the electric motor is disposed to be inclined with respect to a vertical line passing through an axis of the tunnel.   
     
     
         12 . The personal watercraft according to  claim 11 , further comprising:
 a luggage room disposed at a front portion in the boat body; and   an electric motor for obtaining the propulsive force in the thrust direction, wherein   the electric motor is disposed at a position vertically overlapping the luggage room.   
     
     
         13 . The personal watercraft according to  claim 1 , further comprising:
 a luggage room disposed at a front portion in the boat body;   an electric motor for obtaining the propulsive force in the thrust direction; and   a cover that covers a protruding portion of the electric motor to the luggage room.   
     
     
         14 . The personal watercraft according to  claim 1 , further comprising:
 a drive source that applies a rotational driving force to the impeller shaft;   an electric motor for obtaining the propulsive force in the thrust direction; and   a partition wall that partitions an area in which the drive source is accommodated and an area in which the electric motor is disposed.   
     
     
         15 . A personal watercraft propelled by a jet stream, the personal watercraft comprising:
 a boat body;   a jet pump including an impeller that is disposed at a rear portion of the boat body and generates a propulsive force, and an impeller shaft that rotates the impeller; and   a side thruster that generates a water flow in a thrust direction intersecting a front-rear direction of the boat body relative to the boat body, and has a water flow generation position set at a height position equal to or lower than a virtual line extending in an extending direction of the impeller shaft in front of the impeller.   
     
     
         16 . A personal watercraft propelled by a jet stream, the personal watercraft comprising:
 a boat body;   a jet pump including an impeller that is disposed at a rear portion of the boat body and generates a propulsive force, and an impeller shaft that rotates the impeller;   a stabilizer disposed at a rear portion and on a side portion of the boat body; and   a side thruster that generates a water flow in a thrust direction intersecting a front-rear direction of the boat body relative to the boat body, and has a water flow generation position located in front of the impeller and below the stabilizer.