A marine propulsion unit includes a stern drive mounted to a transom. The stern drive comprises an upper unit enclosed in a stern drive housing and a lower unit enclosed in a gearbox housing; wherein the gearbox housing contains a gearbox arranged to drive at least one propeller. The propulsion unit further comprises at least two electric motors arranged in the stern drive housing, which electric motors are mounted with vertical output shafts; a planetary gear set arranged between the at least two electric motors and the gearbox, and a vertical shaft that is attached to a ring gear of the planetary gear set at its upper end and is connected to the gearbox at its lower end; wherein the output shaft of each electric motor is connected to a planetary gear arranged in the planetary gear set to drive the ring gear and the vertical shaft connected to the gearbox.

A submarine drive system of a submarine, having a drive shaft, a drive propeller coupled to the drive shaft (2), and an electric motor for driving the drive shaft. A main drive having at least one first electric motor is designed for full-load operation and is or can be coupled to the drive shaft on the drive side, and an additional drive having at least one second electric motor is designed for part-load operation for creep operation or submerged operation of the submarine and likewise is or can be coupled to the drive shaft on the drive side.

A system for providing marine propulsion is provided including an input shaft driven by a prime mover, a pinion gear coupled to the input shaft, a plurality of planet gears coupled to the pinion gear, a planet carrier having the plurality of planet gears rotationally mounted thereto, and a ring gear surrounding the planet gears and coupled thereto. The planet carrier and ring gear are coupled to internal and external output shafts that are coaxially aligned, which are coupled to aft and forward propulsor elements. The ring gear and planet carrier rotate in opposite directions to provide contra-rotating forward and aft propulsor elements. The ring gear and planet gear are each coupled to rotation altering devices that, when at least one is activated, the rotation of both the planet carrier and ring gear will be altered, thereby altering the rotation of the propulsor elements.

A submarine drive system of a submarine, having a drive shaft, a drive propeller coupled to the drive shaft (2), and an electric motor for driving the drive shaft. A main drive having at least one first electric motor is designed for full-load operation and is or can be coupled to the drive shaft on the drive side, and an additional drive having at least one second electric motor is designed for part-load operation for creep operation or submerged operation of the submarine and likewise is or can be coupled to the drive shaft on the drive side.

A braking system for waterborne propeller driven vessel which, upon activating a brake pedal or similar actuation device causes the vessel to almost immediately stop its forward movement. The system initiates a burst of highly amplified horsepower and torque, created by a controlled pulse of electrical power released from a bank of fully charged ultracapacitors. This pulse of electrical power is sent directly to AC induction-driven motors, causing oversized propellers to immediately rotate astern, thereby generating a reverse thrust in opposition to the vessel's forward movement sufficient to stop the vessel. The horsepower and torque produced by the braking system and operation of the present invention will also cause the oversize propellers to transmit this tremendous power into the water, without cavitation, to assist in stopping vessel movement.

A braking system for waterborne propeller driven vessel which, upon activating a brake pedal or similar actuation device causes the vessel to almost immediately stop its forward movement. The system initiates a burst of highly amplified horsepower and torque, created by a controlled pulse of electrical power released from a bank of fully charged ultracapacitors. This pulse of electrical power is sent directly to AC induction-driven motors, causing oversized propellers to immediately rotate astern, thereby generating a reverse thrust in opposition to the vessel's forward movement sufficient to stop the vessel. The horsepower and torque produced by the braking system and operation of the present invention will also cause the oversize propellers to transmit this tremendous power into the water, without cavitation, to assist in stopping vessel movement.

A system for providing marine propulsion is provided including an input shaft driven by a prime mover, a pinion gear coupled to the input shaft, a plurality of planet gears coupled to the pinion gear, a planet carrier having the plurality of planet gears rotationally mounted thereto, and a ring gear surrounding the planet gears and coupled thereto. The planet carrier and ring gear are coupled to internal and external output shafts that are coaxially aligned, which are coupled to aft and forward propulsor elements. The ring gear and planet carrier rotate in opposite directions to provide contra-rotating forward and aft propulsor elements. The ring gear and planet gear are each coupled to rotation altering devices that, when at least one is activated, the rotation of both the planet carrier and ring gear will be altered, thereby altering the rotation of the propulsor elements.