Electric Marine Surface Drive

Abstract

A marine articulated surface drive propulsion system is provided with a housing construction that allows the direct application of an electric motor for power onto the drive structure. Alternatively, it can include a power transmitting element for reducing the rate of rotation or the position of the motor shaft with respect to the propeller shaft. The drive can be retrofitted to existing boat hulls and does not require a dedicated hull. The electric motor can be fitted to the surface drive housing on the inside of the transom. It is contemplated that an electric motor with very small dimensions can be mounted in the drive thrust tube and ball socket, eliminating the need for U joints. Notably, if the propeller is left free wheeling it becomes the propulser for the electric motor to become a generator and recharge the batteries.

1 . A surface drive for a marine vehicle comprising:
 a support housing;   at least one propeller wherein a portion of the propeller is above a water surface thereby substantially reducing underwater drag;   at least one electric motor coupled to at least one propeller, the motor including a motor control device for actuating the electric motor and selecting a electric motor speed and a rotation direction; and   at least one shaft that couples the electric motor to the propeller, and a shaft carrier, wherein at least a portion of the at least one shaft extends through the shaft carrier.   
     
     
         2 . The drive of  claim 1 , wherein at least one electric motor is mounted within the support housing. 
     
     
         3 . The drive of  claim 1 , wherein at least one electric motor is mounted within the marine vehicle. 
     
     
         4 . The drive of  claim 1 , wherein the at least one shaft includes the electric motor is securably attached to the propeller shaft. 
     
     
         5 . The drive of  claim 1 , wherein the at least one shaft includes a drive shaft and a propeller shaft, and wherein the electric motor is attached to the drive shaft that is coupled to the propeller shaft, and wherein the at least one propeller is coupled to the propeller shaft. 
     
     
         6 . The drive of  claim 1 , further comprising a ball joint within the support housing whereby an angle of the propeller with respect to the marine vehicle may be changed. 
     
     
         7 . The drive of  claim 6 , wherein the electric motor is securably mounted within the ball joint. 
     
     
         8 . The drive of  claim 6 , further comprising an articulated trimming arm having an adjustable length and at least one movable joint at an arm end with an arm forward end connecting to the marine vehicle and an arm rear end connected to about the top of the shaft carrier such that the arm is substantially parallel to and above a shaft long axis whereby the articulated trimming arm may be lengthened or shortened thereby rotating the ball joint substantially downwards and upwards, respectively, thereby controlling a portion of the propeller that is submerged and a depth of submersion. 
     
     
         9 . The drive of  claim 6 , further comprising at least one articulated steering arm having an adjustable length and at least one movable joint at an arm end with an arm rear end connecting to about the side of the shaft carrier and an arm forward end connected forward of a pivot point of the ball joint so that the arm forward end is at least substantially horizontally displaced from the shaft long axis, whereby the articulated steering arm may be lengthened or shortened thereby rotating the ball joint to either side controlling the horizontal angle of the propeller shaft relative to the marine vehicle for steering. 
     
     
         10 . The drive of  claim 9 , wherein a forward end of the articulated steering arm forward end is securably mounted to the marine vehicle. 
     
     
         11 . The drive of  claim 9 , wherein the forward end of the articulated steering arm forward end is securably mounted to about the side of the support housing and forward of a ball joint pivot point. 
     
     
         12 . The drive of  claim 9 , further comprising a second articulated steering arm. 
     
     
         13 . The drive of  claim 6 , wherein the shaft comprises at least a forward drive shaft and a propeller shaft with a coupling therebetween whereby rotational movement from the drive shaft portion is transmitted to the propeller shaft portion while allowing for at least some angular displacement between a long axis of the drive shaft and a long axis of the propeller shaft. 
     
     
         14 . The drive of  claim 13 , wherein the coupling is a universal joint. 
     
     
         15 . The drive of  claim 1 , wherein the shaft comprises at least a forward drive shaft and a propeller shaft with a power transmission unit therebetween wherein the power transmission transmits rotational movement from the forward drive shaft to the propeller shaft with at least one of the following: a reduced rotational speed of the propeller shaft or a displacement between the rotational axes of the forward drive shaft and the propeller shaft. 
     
     
         16 . The drive of  claim 15 , wherein the power transmission unit comprises at least one gear connected to the forward drive shaft and a at least one gear connected to the propeller shaft, wherein the gears are selected from at least one of a group of spur gears, planetary gears, helical gears, herringbone gears, straight bevel gears, spiral bevel gears, hypoid gears, and worm gears. 
     
     
         17 . The drive of  claim 1 , further comprising a motor drive connected to the motor control device, an electric power source, and at least one electric motor wherein the motor drive provides power to the electric motor from the electric power source based on a speed control signal and a direction control signal from the motor control device. 
     
     
         18 . The drive of  claim 1 , further comprising an power conversion device connected to the motor control device, and an electric power storage device, wherein the inverter provides power to the electric power storage device from the electric motor when it is not being driven, but is generating an electric current. 
     
     
         19 . A surface drive for a marine vehicle comprising:
 a support housing securably mounted to the marine vehicle;   at least one electric motor by which the at least one propeller is drivable, the motor having a control device for actuating the electric motor and selecting a electric motor speed and a rotation direction; and   an electric power source;   at least one propeller wherein the position of the propeller with respect to the marine vehicle is vertically controllable such that a portion of the propeller may be above a water surface thereby substantially reducing underwater drag; and wherein the position of the propeller with respect to the marine vehicle is horizontally controllable to steer the direction of the marine vehicle; and   at least one shaft having a forward end connected to the electric motor, a rear end connected to the propeller, and a shaft carrier wherein the shaft extends therethrough.   
     
     
         20 . The drive of  claim 19 , wherein the electric motor is securably mounted in one of a group including a support housing and the shaft carrier.