An outboard motor includes: an upper case supported on a hull; a lower case pivotably supported on the upper case; a first drive source disposed within the upper case; a planetary gear mechanism connected to the first drive source via an upper drive shaft; a propeller shaft connected to the planetary gear mechanism via a lower drive shaft; and a second drive source that provides the lower case with a torque. The planetary gear mechanism includes a sun gear, a planetary carrier supporting planetary gears and connected to an upper end of the lower drive shaft, and an internal gear. One of the sun gear and the internal gear is connected to the lower end of the upper drive shaft, and the other is connected to the lower case to provide the lower case with a torque in a direction opposite to a rotation direction of the lower drive shaft.

An outboard motor includes: an upper case supported on a hull; a lower case pivotably supported on the upper case; a first drive source disposed within the upper case; a planetary gear mechanism connected to the first drive source via an upper drive shaft; a propeller shaft connected to the planetary gear mechanism via a lower drive shaft; and a second drive source that provides the lower case with a torque. The planetary gear mechanism includes a sun gear, a planetary carrier supporting planetary gears and connected to an upper end of the lower drive shaft, and an internal gear. One of the sun gear and the internal gear is connected to the lower end of the upper drive shaft, and the other is connected to the lower case to provide the lower case with a torque in a direction opposite to a rotation direction of the lower drive shaft.

The present invention concerns an outboard propulsion device for a navigational seacraft comprising a propulsion means (4), at least one engine (1) supplying torque to a drive shaft (20) extending out of the engine and driving a transmission shaft (3) intended to supply torque to the propulsion means, the drive shaft and the propulsion shaft being in a fixed relative orientation, and a transmission means (2) connected at the input to the drive shaft (20) in order to receive the engine torque and transmit it at least partially to the transmission shaft. The transmission means (2) modifies the orientation of the engine torque and transmits it, in the form of modified torque, to the transmission shaft (3) to which it is connected at the output, and the transmission shaft (3) is a double universal joint shaft (30, 31) that extends in an inclined manner between the transmission means (2) and the propulsion means (4), the transmission shaft at least partially transmitting the modified torque to the propulsion means.

A boat propulsion system, OSD-Outboard Stern Drive where single, or multiple marine engines are positioned at boat stern inside boat outer envelope on customized-elevated subfloor and connected to outdrive unit that is attached to boat stern plate. Engine/s are positioned lower than typical outboard engine/s and higher than typical inboard engine/s. Engine compartment is covered by a customized hood and engines are easily accessible from boat floor like typical outboard engine configuration. Drive configuration is like typical sterndrive with engine/s crankshaft in horizontal position that is connected to outdrive unit via cardan joint allowing drive tilting up and down. The main purpose of using OSD would be use of one or two Diesel or gasoline marine engines of existing design thus eliminating use of 2-6 large outboards for boats longer than 25 feet and outboard like access to engines for maintenance while using sturdier marine engines and providing much simpler boat/engine configuration.

A boat propulsion system, OSD-Outboard Stern Drive where single, or multiple marine engines are positioned at boat stern inside boat outer envelope on customized-elevated subfloor and connected to outdrive unit that is attached to boat stern plate. Engine/s are positioned lower than typical outboard engine/s and higher than typical inboard engine/s. Engine compartment is covered by a customized hood and engines are easily accessible from boat floor like typical outboard engine configuration. Drive configuration is like typical sterndrive with engine/s crankshaft in horizontal position that is connected to outdrive unit via cardan joint allowing drive tilting up and down. The main purpose of using OSD would be use of one or two Diesel or gasoline marine engines of existing design thus eliminating use of 2-6 large outboards for boats longer than 25 feet and outboard like access to engines for maintenance while using sturdier marine engines and providing much simpler boat/engine configuration.

A vertical-input outboard-motor angled-drive lower unit apparatus and method for improved operations in shallow, muddy, marshy water or water choked with vegetation or obstacles. Vertically applied single-direction rotational power from an outboard motor engine is transferred to operator-controlled forward and reverse rotational power applied at an acute angle to the horizontal water surface. The apparatus is cooled by an external flow of water without being taken into any port which might become blocked. A thrust redirection plate reflects otherwise wasted propeller thrust, especially when operating in reverse, for more efficient operation and reduced churning of the water surface. An angled skeg and the angled orientation of the output shaft and housing deflect obstructions.

A portable propulsion system for a watercraft may include a shaft, a propeller, an outer casing, and a flexible strap. The shaft may have a prop end section, a drive end section, and a rotational axis extending from the prop end section to the drive end section. The propeller may be connected to the prop end section of the shaft. The drive end section may be configured for removable connection to a driver for rotation of the propeller via rotation of the shaft about the rotational axis to propel the watercraft. The outer casing may be disposed around the shaft. The flexible strap may have first and second end sections connected to the outer casing in respective first and second regions.

A portable propulsion system for a watercraft may include a shaft, a propeller, an outer casing, and a flexible strap. The shaft may have a prop end section, a drive end section, and a rotational axis extending from the prop end section to the drive end section. The propeller may be connected to the prop end section of the shaft. The drive end section may be configured for removable connection to a driver for rotation of the propeller via rotation of the shaft about the rotational axis to propel the watercraft. The outer casing may be disposed around the shaft. The flexible strap may have first and second end sections connected to the outer casing in respective first and second regions.

A propeller propulsion system for a watercraft includes at least one electric motor and a propeller which can be driven by the electric motor. The propeller is a surface piercing propeller. The propulsion system includes a box-like body having a side wall on which the electric motor is fixed and a cover part on which an outdrive of the surface piercing propeller is applied. The side wall and the cover part include holes through which a shaft of the motor and a shaft of the outdrive respectively pass. The box-like body includes means for transmission of motion from the drive shaft to the outdrive shaft, and the propulsion system includes means for fixing the box-like body to a transom of the watercraft.

A portable propulsion system for a watercraft may include a shaft, a propeller, an outer casing, and a flexible strap. The shaft may have a prop end section, a drive end section, and a rotational axis extending from the prop end section to the drive end section. The propeller may be connected to the prop end section of the shaft. The drive end section may be configured for removable connection to a driver for rotation of the propeller via rotation of the shaft about the rotational axis to propel the watercraft. The outer casing may be disposed around the shaft. The flexible strap may have first and second end sections connected to the outer casing in respective first and second regions.