Modular hybrid propulsion unit for watercraft

Abstract

A modular hybrid propulsion unit is disclosed that is mountable to a watercraft. According to an example, the modular hybrid propulsion unit includes a housing configured to fit within a complementary housing receiver on a topside of the watercraft, and a rotational output coupling configured to rotationally engage with a rotational input coupling for a propeller of the watercraft. The propulsion unit further includes an electric motor within the housing, the electric motor having a motor shaft connected to the rotational output coupling for providing an electrically powered rotational input to the rotational output coupling. The propulsion unit further includes a crank having one or more crank arms. The crank is connected to the rotational output coupling for providing a human powered rotational input to the rotational output coupling independent of the electrically powered rotational input by the electric motor.

1 . A method performed by an electronic control system for a modular hybrid propulsion unit of a watercraft, the method comprising:
 providing, to an electric motor of the modular hybrid propulsion unit, power of a first polarity to rotate a propeller of the watercraft in a first direction that corresponds to a forward rotation direction of the propeller;   varying a level of the power provided to the electric motor in response to a level of human powered rotational input received via a crank of the modular hybrid propulsion unit; and   cutting power to the electric motor in response to a physical interaction with a power cut off switch positioned on an exterior housing of the modular hybrid drive unit.   
     
     
         2 . The method of  claim 1 , wherein the physical interaction includes disengagement of the power cut off switch. 
     
     
         3 . The method of  claim 2 , wherein disengagement of the power cut off switch includes movement of a drive retraction control lever from physical contact with the power cut off switch positioned on the exterior housing of the modular drive unit. 
     
     
         4 . The method of  claim 3 , wherein movement of the drive retraction control lever from contact with the power cut off switch includes moving a daggerboard of the watercraft toward a retracted position. 
     
     
         5 . The method of  claim 1 , wherein providing power of the first polarity to the electric motor and varying the level of electric assist is performed during a first mode of operation; and
 wherein the method further comprises:
 during a second mode of operation, providing, to the electric motor of the modular hybrid propulsion unit, power of a second polarity to rotate the propeller of the watercraft in a second direction opposite the first direction; and 
 varying operation between the first mode and the second mode responsive to a control input. 
   
     
     
         6 . The method of  claim 5 , wherein the control input is received via a forward and reverse mode selector. 
     
     
         7 . The method of  claim 5 , wherein the crank is connected to a coupling of the propeller via a directional clutch that engages with the coupling when the crank is rotated in a first direction that corresponds to the forward rotation direction of the propeller, and disengages with the coupling when the crank is rotated in a second direction opposite the first direction that corresponds to the reverse rotation direction of the propeller. 
     
     
         8 . The method of  claim 1 , further comprising:
 further varying the electrically powered rotational input provided to rotation of the propeller by the electric motor responsive to a control input.   
     
     
         9 . The method of  claim 8 , wherein the control input is received via a throttle. 
     
     
         10 . The method of  claim 1 , wherein the level of human powered rotational input received via the crank includes a rotation rate of the crank. 
     
     
         11 . A method performed by an electronic control system for a modular hybrid propulsion unit of a watercraft, the method comprising:
 during a first mode of operation,
 providing, to an electric motor of the modular hybrid propulsion unit, power of a first polarity to rotate a propeller of the watercraft in a first direction that corresponds to a forward rotation direction of the propeller, and 
 varying a level of electric assist provided by the electric motor by an electrically powered rotational input to rotation of the propeller responsive to a level of human powered rotational input received via a crank of the modular hybrid propulsion unit; 
   during a second mode of operation, providing, to the electric motor of the modular hybrid propulsion unit, power of a second polarity to rotate the propeller of the watercraft in a second direction opposite the first direction;   varying operation between the first mode and the second mode responsive to a control input; and   cutting power to the electric motor responsive to a physical interaction with a power cut off switch positioned on an exterior housing of the modular hybrid drive unit.   
     
     
         12 . The method of  claim 11 , wherein the physical interaction includes disengagement of the power cut off switch. 
     
     
         13 . The method of  claim 12 , wherein disengagement of the power cut off switch includes movement of a drive retraction control lever from physical contact with the power cut off switch positioned on the exterior housing of the modular drive unit. 
     
     
         14 . The method of  claim 13 , wherein movement of the drive retraction control lever from contact with the power cut off switch includes moving a daggerboard of the watercraft toward a retracted position. 
     
     
         15 . The method of  claim 11 , wherein the control input is received via a forward and reverse mode selector. 
     
     
         16 . The method of  claim 11 , wherein the crank is connected to a coupling of the propeller via a directional clutch that engages with the coupling when the crank is rotated in a first direction that corresponds to the forward rotation direction of the propeller, and disengages with the coupling when the crank is rotated in a second direction opposite the first direction that corresponds to the reverse rotation direction of the propeller. 
     
     
         17 . The method of  claim 11 , further comprising:
 further varying the electrically powered rotational input provided to rotation of the propeller by the electric motor responsive to an additional control input.   
     
     
         18 . The method of  claim 17 , wherein the additional control input is received via a throttle. 
     
     
         19 . The method of  claim 11 , wherein the level of human powered rotational input received via the crank includes a rotation rate of the crank. 
     
     
         20 . A method performed using a modular hybrid propulsion unit of a watercraft, comprising:
 inserting the modular hybrid propulsion unit into a receptacle of the watercraft to engage a rotational output coupling of the modular hybrid propulsion unit with a rotational input coupling for a propeller of the watercraft; and   via an electronic control system of the modular hybrid propulsion unit:
 providing, to an electric motor of the modular hybrid propulsion unit, power of a first polarity to rotate a propeller of the watercraft in a first direction that corresponds to a forward rotation direction of the propeller; 
 varying a level of electric assist provided by the electric motor by an electrically powered rotational input to rotation of the propeller responsive to a level of human powered rotational input received via a crank of the modular hybrid propulsion unit; and 
 cutting power to the electric motor responsive to retraction of a daggerboard of the watercraft.