Transmission systems and methods are for a marine propulsion device having an internal combustion engine that drives a propulsor. An input shaft is driven into rotation at a non-zero first rotational speed by the internal combustion engine. An output shaft drives the propulsor into rotation at a non-zero second rotational speed. A planetary gearset transfers power from the input shaft to the output shaft. A band brake is on the planetary gearset. Actuation of the band brake effects a gear change in the planetary gearset. A band brake actuator actuates the band brake to effect the gear change. A controller controls the band brake actuator. Based upon one or more operational characteristics of the marine propulsion device the controller is programmed to control the band brake actuator so that the second rotational speed is less than the first rotational speed.

Transmission systems and methods are for a marine propulsion device having an internal combustion engine that drives a propulsor. An input shaft is driven into rotation at a non-zero first rotational speed by the internal combustion engine. An output shaft drives the propulsor into rotation at a non-zero second rotational speed. A planetary gearset transfers power from the input shaft to the output shaft. A band brake is on the planetary gearset. Actuation of the band brake effects a gear change in the planetary gearset. A band brake actuator actuates the band brake to effect the gear change. A controller controls the band brake actuator. Based upon one or more operational characteristics of the marine propulsion device the controller is programmed to control the band brake actuator so that the second rotational speed is less than the first rotational speed.

A reduction reverse gear according to the invention of the present application includes: an input shaft to which rotational driving force from a main engine is input; a front-reverse housing accommodating forward-backward switching mechanisms with which the rotational driving force from the input shaft is switched among forward, neutral, and backward; an output shaft through which the rotational driving force from the forward-backward switching mechanisms is output; and a reduction housing accommodating a reduction mechanism with which the rotational driving force from the output shaft is reduced to be transmitted to a propeller shaft. The housings are detachably coupled to each other on front and rear sides in an axial direction. The input shaft and the output shaft are arranged on the same plane while facing each other.

A reduction reverse gear according to the invention of the present application includes: an input shaft to which rotational driving force from a main engine is input; a front-reverse housing accommodating forward-backward switching mechanisms with which the rotational driving force from the input shaft is switched among forward, neutral, and backward; an output shaft through which the rotational driving force from the forward-backward switching mechanisms is output; and a reduction housing accommodating a reduction mechanism with which the rotational driving force from the output shaft is reduced to be transmitted to a propeller shaft. The housings are detachably coupled to each other on front and rear sides in an axial direction. The input shaft and the output shaft are arranged on the same plane while facing each other.

Transmission systems and methods are for a marine propulsion device having an internal combustion engine that drives a propulsor. An input shaft is driven into rotation at a non-zero first rotational speed by the internal combustion engine. An output shaft drives the propulsor into rotation at a non-zero second rotational speed. A planetary gearset transfers power from the input shaft to the output shaft. A band brake is on the planetary gearset. Actuation of the band brake effects a gear change in the planetary gearset. A band brake actuator actuates the band brake to effect the gear change. A controller controls the band brake actuator. Based upon one or more operational characteristics of the marine propulsion device the controller is programmed to control the band brake actuator so that the second rotational speed is less than the first rotational speed.

Transmission systems and methods are for a marine propulsion device having an internal combustion engine that drives a propulsor. An input shaft is driven into rotation at a non-zero first rotational speed by the internal combustion engine. An output shaft drives the propulsor into rotation at a non-zero second rotational speed. A planetary gearset transfers power from the input shaft to the output shaft. A band brake is on the planetary gearset. Actuation of the band brake effects a gear change in the planetary gearset. A band brake actuator actuates the band brake to effect the gear change. A controller controls the band brake actuator. Based upon one or more operational characteristics of the marine propulsion device the controller is programmed to control the band brake actuator so that the second rotational speed is less than the first rotational speed.

A vessel propulsion apparatus includes an engine, an electric motor located farther forward than a propeller, a propeller shaft, a first transmission that defines a first transmission path extending from the engine to the propeller shaft to transmit power of the engine to the propeller shaft along the first transmission path, and a second transmission that defines a second transmission path, different from the first transmission path, extending from the electric motor to the propeller shaft to transmit power of the electric motor to the propeller shaft along the second transmission path.

A propulsion device for a ship capable of preventing idling of a propeller without any limitation on the type of clutch. The propulsion device includes: a forward and reverse switching clutch for transmitting the driving power from an input shaft to a forward gear or a reverse gear; a forward one-way clutch, disposed between the input shaft and the forward gear, for connecting the forward gear and the input shaft when the forward gear is rotated at a higher speed than that of the input shaft; and a reverse one-way clutch, disposed between the input shaft and the reverse gear, for connecting the reverse gear and the input shaft when the reverse gear is rotated at a higher speed than that of the input shaft.

A propulsion device for a ship capable of preventing idling of a propeller without any limitation on the type of clutch. The propulsion device includes: a forward and reverse switching clutch for transmitting the driving power from an input shaft to a forward gear or a reverse gear; a forward one-way clutch, disposed between the input shaft and the forward gear, for connecting the forward gear and the input shaft when the forward gear is rotated at a higher speed than that of the input shaft; and a reverse one-way clutch, disposed between the input shaft and the reverse gear, for connecting the reverse gear and the input shaft when the reverse gear is rotated at a higher speed than that of the input shaft.

A vessel propulsion apparatus includes an engine, an electric motor located farther forward than a propeller, a propeller shaft, a first transmission that defines a first transmission path extending from the engine to the propeller shaft to transmit power of the engine to the propeller shaft along the first transmission path, and a second transmission that defines a second transmission path, different from the first transmission path, extending from the electric motor to the propeller shaft to transmit power of the electric motor to the propeller shaft along the second transmission path.