Marine vessel maneuvering system and marine vessel

A marine vessel maneuvering system includes a controller configured or programmed to, when an operator is operated to move a marine vessel forward, perform a forward acceleration assist control to perform a control to generate a forward propulsive force in a propulsion generator of a marine propulsion unit that is not used when the operator is operated to move the marine vessel diagonally forward among three or more marine propulsion units.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of priority to Japanese Patent Application No. 2021-099010 filed on Jun. 14, 2021. The entire contents of this application are hereby incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a marine vessel maneuvering system and a marine vessel, and more particularly, the present invention relates to a marine vessel maneuvering system and a marine vessel each including three or more marine propulsion units.

2. Description of the Related Art

A marine vessel maneuvering system including three or more marine propulsion units is known in general. Such a marine vessel maneuvering system is disclosed in Japanese Patent Laid-Open No. 2014-073700, for example.

Japanese Patent Laid-Open No. 2014-073700 discloses a marine vessel maneuvering system including three or more marine propulsion units. In the marine vessel maneuvering system described in Japanese Patent Laid-Open No. 2014-073700, a controller controls the three or more marine propulsion units based on an operation on an operator such that a marine vessel is moved forward and diagonally forward, for example.

Although not described in Japanese Patent Laid-Open No. 2014-073700, in a conventional marine vessel maneuvering system as described in Japanese Patent Laid-Open No. 2014-073700, at least when a marine vessel is moved diagonally forward, some of the three or more marine propulsion units may not be used in order to maintain the right-left balance of the marine vessel. For example, in a marine vessel maneuvering system including three marine propulsion units, a central marine propulsion unit is not used to move a marine vessel forward, to move the marine vessel diagonally forward, or to switch between forward movement and diagonal forward movement, but one or both of portside and starboard marine propulsion units are used. That is, while the marine vessel maneuvering system switches between forward movement and diagonal forward movement of the marine vessel, only one or both of the portside and starboard marine propulsion units are used without using the central marine propulsion unit such that the right-left balance of the marine vessel is maintained. However, the central marine propulsion unit is not used to move the marine vessel forward, and thus in a relatively large (large mass) marine vessel such as one including three or more marine propulsion units, acceleration at the time of moving the marine vessel forward is relatively small. Therefore, it is desired to improve acceleration at the time of moving a marine vessel forward when the marine vessel includes three or more marine propulsion units and some of the marine propulsion units are not used at least to move the marine vessel diagonally forward.

SUMMARY OF THE INVENTION

Preferred embodiments of the present invention provide marine vessel maneuvering systems and marine vessels that each improve acceleration at the time of moving marine vessels forward when the marine vessels include three or more marine propulsion units and some of the marine propulsion units are not used at least to move the marine vessels diagonally forward.

A marine vessel maneuvering system according to a preferred embodiment of the present invention includes three or more marine propulsion units each including a propulsion generator to generate a propulsive force to propel a marine vessel, an operator to receive at least operations to move the marine vessel forward and diagonally forward, and a controller configured or programmed to control the three or more marine propulsion units based on an operation on the operator, and configured or programmed to, when the operator is operated to move the marine vessel forward, perform a forward acceleration assist control to perform a control to generate a forward propulsive force in the propulsion generator of a marine propulsion unit that is not used when the operator is operated to move the marine vessel diagonally forward among the three or more marine propulsion units.

In a marine vessel maneuvering system according to a preferred embodiment of the present invention, the controller is configured or programmed to, when the operator is operated to move the marine vessel forward, perform the forward acceleration assist control to perform a control to generate a forward propulsive force in the propulsion generator of the marine propulsion unit that is not used when the operator is operated to move the marine vessel diagonally forward. Accordingly, the propulsion generator of the marine propulsion unit that is not used when the operator is operated to move the marine vessel diagonally forward assists the forward propulsive forces such that the acceleration of the marine vessel at the time of moving the marine vessel forward is improved. That is, the marine propulsion unit that is not used to maintain the right-left balance of the marine vessel when the marine vessel is moved diagonally forward is used as a marine propulsion unit that assists the forward propulsive forces in the propulsion generators. Furthermore, in the structure including the three or more marine propulsion units, some of the marine propulsion units are not used at least to move the marine vessel diagonally forward such that the right-left balance of the marine vessel is maintained. Therefore, the acceleration at the time of moving the marine vessel forward is improved while the right-left balance of the marine vessel is maintained.

In a marine vessel maneuvering system according to a preferred embodiment of the present invention, the three or more marine propulsion units preferably include a portside marine propulsion unit located on a port side, a starboard marine propulsion unit located on a starboard side, and a central marine propulsion unit located between the portside marine propulsion unit and the starboard marine propulsion unit, and the controller is preferably configured or programmed to perform the forward acceleration assist control to generate a forward propulsive force in the propulsion generator of the central marine propulsion unit that is not used when the operator is operated to move the marine vessel diagonally forward. Accordingly, the central marine propulsion unit is not used to move the marine vessel diagonally forward, but the portside marine propulsion unit and the starboard marine propulsion unit are used, and thus at least when the marine vessel is moved diagonally forward, the right-left balance of the marine vessel is easily maintained.

In a marine vessel maneuvering system according to a preferred embodiment of the present invention, the controller is preferably configured or programmed to perform the forward acceleration assist control to temporarily generate a forward propulsive force in the propulsion generator. Accordingly, after the marine vessel is accelerated in a forward movement direction and reaches a certain speed, the assist of the forward propulsive forces in the propulsion generators that is no longer needed is terminated.

In a marine vessel maneuvering system according to a preferred embodiment of the present invention, the operator preferably includes a joystick, and the controller is preferably configured or programmed to perform the forward acceleration assist control when the joystick is tilted forward. Accordingly, a direction in which the joystick is tilted and a direction in which the marine vessel is moved match as a forward direction, and thus an operation is performed in an intuitively easy-to-understand state to perform the forward acceleration assist control. Furthermore, the joystick is generally operated not only to move the marine vessel forward but also to move the marine vessel diagonally forward in an intuitively easy-to-understand state, and thus the joystick is particularly effective as an “operator” in the structure in which the forward acceleration assist control is performed in connection with the operation to move the marine vessel forward and the operation to move the marine vessel diagonally forward.

In a marine vessel maneuvering system according to a preferred embodiment of the present invention, the controller is preferably configured or programmed to not perform the forward acceleration assist control upon the operator being operated to move the marine vessel forward when the marine vessel is previously moved diagonally forward, and to perform the forward acceleration assist control upon the operator being operated to move the marine vessel forward when a propulsive force of the propulsion generator is previously not generated. Accordingly, when some of the marine propulsion units are not used such that it may be difficult to maintain the right-left balance of the marine vessel, such as when the marine vessel is switched from a diagonal forward movement state to a forward movement state, the forward propulsive forces in the propulsion generators are not assisted such that the difficulty in maintaining the right-left balance of the marine vessel due to not using some of the marine propulsion units is significantly reduced or prevented. Furthermore, when the assist of the forward propulsive forces in the propulsion generators is particularly needed, such as when a state in which the propulsive forces of the propulsion generators are not generated is switched to a state in which the marine vessel is moved forward, the forward propulsive forces in the propulsion generators are effectively assisted.

In such a case, the three or more marine propulsion units preferably include a portside marine propulsion unit located on a port side, a starboard marine propulsion unit located on a starboard side, and a central marine propulsion unit located between the portside marine propulsion unit and the starboard marine propulsion unit, and the controller is preferably configured or programmed to control both the portside marine propulsion unit and the starboard marine propulsion unit to move the marine vessel forward without performing the forward acceleration assist control using the central marine propulsion unit upon the operator being operated to move the marine vessel forward when the marine vessel is moved diagonally forward by either the portside marine propulsion unit or the starboard marine propulsion unit, and to perform the forward acceleration assist control to move the marine vessel forward using the central marine propulsion unit, which is not used when the operator is operated to move the marine vessel diagonally forward, in addition to both the portside marine propulsion unit and the starboard marine propulsion unit upon the operator being operated to move the marine vessel forward when the propulsive force of the propulsion generator is previously not generated. Accordingly, when some of the marine propulsion units are not used such that it may be difficult to maintain the right-left balance of the marine vessel, such as when the marine vessel is switched from the diagonal forward movement state to the forward movement state, the forward propulsive forces in the propulsion generators are not assisted by the central marine propulsion unit and both the portside marine propulsion unit and the starboard marine propulsion unit move the marine vessel forward such that the difficulty in maintaining the right-left balance of the marine vessel due to not using some of the marine propulsion units is easily significantly reduced or prevented. Furthermore, when the assist of the forward propulsive forces in the propulsion generators is particularly needed, such as when a state in which the propulsive forces of the propulsion generators are not generated is switched to a state in which the marine vessel is moved forward, the central marine propulsion unit is added to both the portside marine propulsion unit and the starboard marine propulsion unit such that the forward propulsive forces in the propulsion generators are assisted at the center of the marine vessel in the right-left direction without decreasing the balance of the marine vessel in the right-left direction.

In a marine vessel maneuvering system according to a preferred embodiment of the present invention, the controller is preferably configured or programmed to perform the forward acceleration assist control to gradually decrease a forward propulsive force temporarily generated in the propulsion generator until the forward propulsive force becomes zero. Accordingly, the assist of the forward propulsive forces in the propulsion generators is terminated relatively smoothly, and thus good navigation stability of the marine vessel is maintained as compared with a case in which the temporarily generated propulsive force changes rapidly.

In such a case, the controller is preferably configured or programmed to perform the forward acceleration assist control to gradually decrease the forward propulsive force temporarily generated in the propulsion generator until the forward propulsive force becomes zero after the forward propulsive force is maintained in a constant state for a predetermined first time. Accordingly, good navigation stability of the marine vessel is maintained while the marine vessel is sufficiently accelerated in the forward movement direction until the marine vessel reaches a certain speed before the assist of the forward propulsive forces in the propulsion generators is terminated.

In a marine vessel maneuvering system including the controller configured or programmed to perform the forward acceleration assist control to gradually decrease the forward propulsive force temporarily generated in the propulsion generator until the forward propulsive force becomes zero after the forward propulsive force is maintained in the constant state for the predetermined first time, the controller is preferably configured or programmed to perform the forward acceleration assist control to gradually decrease a forward propulsive force of the propulsion generator operable to temporarily generate the forward propulsive force until the forward propulsive force becomes zero after the forward propulsive force is maintained equal or substantially equal to an average of forward propulsive forces of a plurality of remaining propulsion generators for the predetermined first time. Accordingly, the forward propulsive force temporarily generated in the propulsion generator is set to an appropriate magnitude in accordance with the average of the forward propulsive forces of the plurality of propulsion generators other than the propulsion generator that temporarily generates the forward propulsive force.

In a marine vessel maneuvering system according to a preferred embodiment of the present invention, the propulsion generator of each of the three or more marine propulsion units is preferably driven by an engine. Accordingly, in the structure including the three or more marine propulsion units each including the propulsion generator driven by the engine, some of the marine propulsion units are not used at least to move the marine vessel diagonally forward such that the acceleration at the time of moving the marine vessel forward is improved while the right-left balance of the marine vessel is maintained.

In a marine vessel maneuvering system according to a preferred embodiment of the present invention, the three or more marine propulsion units preferably include five marine propulsion units aligned in a right-left direction of the marine vessel, and the controller is preferably configured or programmed to perform the forward acceleration assist control to generate a forward propulsive force in the propulsion generator of one marine propulsion unit that is located at a center and is not used when the operator is operated to move the marine vessel diagonally forward among the five marine propulsion units. Accordingly, in the large marine vessel including the five marine propulsion units, the acceleration at the time of moving the marine vessel forward is particularly small when the forward propulsive forces in the propulsion generators are not assisted, and thus the structure including the five marine propulsion units is effectively applied to a structure that improves the acceleration at the time of moving the marine vessel forward.

In a marine vessel maneuvering system according to a preferred embodiment of the present invention, the operator is preferably operable to receive an operation to move the marine vessel laterally in addition to the operations to move the marine vessel forward and diagonally forward, and the controller is preferably configured or programmed to perform the forward acceleration assist control to generate a forward propulsive force in the propulsion generator of a marine propulsion unit that is not used when the operator is operated to move the marine vessel diagonally forward and is operable to generate a backward propulsive force in the propulsion generator when the operator is operated to move the marine vessel laterally among the three or more marine propulsion units. In the marine vessel maneuvering system including the three or more marine propulsion units, when the marine vessel is moved laterally, either the portside marine propulsion unit or the starboard marine propulsion unit generates a forward propulsive force in the propulsion generator, and either the starboard marine propulsion unit or the portside marine propulsion unit and the central marine propulsion unit generate backward propulsive forces in the propulsion generator. That is, while lateral movement of the marine vessel is switched to diagonal forward movement of the marine vessel, the forward propulsive force in the propulsion generator of either the portside marine propulsion unit or the starboard marine propulsion unit and the backward propulsive forces in the propulsion generators of either the starboard marine propulsion unit or the portside marine propulsion unit and the central marine propulsion unit are adjusted such that the right-left balance of the marine vessel is maintained. Therefore, with the structure described above, when the marine vessel is moved not only diagonally forward but also laterally, the right-left balance of the marine vessel is maintained. Furthermore, when the marine vessel is moved forward, the marine propulsion unit that is not used to maintain the right-left balance of the marine vessel when the marine vessel is moved diagonally forward and generates a backward propulsive force in the propulsion generator to maintain the balance of the marine vessel when the marine vessel is moved laterally is used as a marine propulsion unit that assists the forward propulsive forces in the propulsion generators.

A marine vessel according to a preferred embodiment of the present invention includes a hull, and three or more marine propulsion units attached to the hull. Each of the three or more marine propulsion units includes a propulsion generator to generate a propulsive force to propel the marine vessel, and the hull includes an operator to receive at least operations to move the marine vessel forward and diagonally forward, and a controller configured or programmed to control the three or more marine propulsion units based on an operation on the operator, and configured or programmed to, when the operator is operated to move the marine vessel forward, perform a forward acceleration assist control to perform a control to generate a forward propulsive force in the propulsion generator of a marine propulsion unit that is not used when the operator is operated to move the marine vessel diagonally forward among the three or more marine propulsion units.

In a marine vessel according to a preferred embodiment of the present invention, the controller is configured or programmed to perform the forward acceleration assist control similar to that of the marine vessel maneuvering system according to preferred embodiments of the present invention described above. Accordingly, similarly to the marine vessel maneuvering system according to preferred embodiments of the present invention described above, the marine propulsion unit that is not used to maintain the right-left balance of the marine vessel when the marine vessel is moved diagonally forward is used as a marine propulsion unit that assists the forward propulsive forces in the propulsion generators. Furthermore, similarly to the marine vessel maneuvering system according to preferred embodiments of the present invention described above, in the structure including the three or more marine propulsion units, some of the marine propulsion units are not used at least to move the marine vessel diagonally forward such that the right-left balance of the marine vessel is maintained. Therefore, the acceleration at the time of moving the marine vessel forward is improved while the right-left balance of the marine vessel is maintained.

In a marine vessel according to a preferred embodiment of the present invention, the three or more marine propulsion units preferably include a portside marine propulsion unit located on a port side, a starboard marine propulsion unit located on a starboard side, and a central marine propulsion unit located between the portside marine propulsion unit and the starboard marine propulsion unit, and the controller is preferably configured or programmed to perform the forward acceleration assist control to generate a forward propulsive force in the propulsion generator of the central marine propulsion unit that is not used when the operator is operated to move the marine vessel diagonally forward. Accordingly, similarly to the marine vessel maneuvering system according to preferred embodiments of the present invention described above, the central marine propulsion unit is not used to move the marine vessel diagonally forward, but the portside marine propulsion unit and the starboard marine propulsion unit are used, and thus at least when the marine vessel is moved diagonally forward, the right-left balance of the marine vessel is easily maintained.

In a marine vessel according to a preferred embodiment of the present invention, the controller is preferably configured or programmed to perform the forward acceleration assist control to temporarily generate a forward propulsive force in the propulsion generator. Accordingly, similarly to the marine vessel maneuvering system according to preferred embodiments of the present invention described above, after the marine vessel is accelerated in a forward movement direction and reaches a certain speed, the assist of the forward propulsive forces in the propulsion generators that is no longer needed is terminated.

In a marine vessel according to a preferred embodiment of the present invention, the operator preferably includes a joystick, and the controller is preferably configured or programmed to perform the forward acceleration assist control when the joystick is tilted forward. Accordingly, similarly to the marine vessel maneuvering system according to preferred embodiments of the present invention described above, a direction in which the joystick is tilted and a direction in which the marine vessel is moved match as a forward direction, and thus an operation is performed in an intuitively easy-to-understand state to perform the forward acceleration assist control. Furthermore, the joystick is generally operated not only to move the marine vessel forward but also to move the marine vessel diagonally forward in an intuitively easy-to-understand state, and thus the joystick is particularly effective as an “operator” in the structure in which the forward acceleration assist control is performed in connection with the operation to move the marine vessel forward and the operation to move the marine vessel diagonally forward.

In a marine vessel according to a preferred embodiment of the present invention, the controller is preferably configured or programmed to not perform the forward acceleration assist control upon the operator being operated to move the marine vessel forward when the marine vessel is previously moved diagonally forward, and to perform the forward acceleration assist control upon the operator being operated to move the marine vessel forward when the marine vessel is stopped. Accordingly, similarly to the marine vessel maneuvering system according to preferred embodiments of the present invention described above, when some of the marine propulsion units are not used such that it may be difficult to maintain the right-left balance of the marine vessel, such as when the marine vessel is switched from a diagonal forward movement state to a forward movement state, the forward propulsive forces in the propulsion generators are not assisted such that the difficulty in maintaining the right-left balance of the marine vessel due to not using some of the marine propulsion units is significantly reduced or prevented. Furthermore, when the assist of the forward propulsive forces in the propulsion generators is particularly needed, such as when a state in which the propulsive forces of the propulsion generators are not generated is switched to a state in which the marine vessel is moved forward, the forward propulsive forces in the propulsion generators are effectively assisted.

In a marine vessel according to a preferred embodiment of the present invention, the controller is preferably configured or programmed to perform the forward acceleration assist control to gradually decrease a forward propulsive force temporarily generated in the propulsion generator until the forward propulsive force becomes zero. Accordingly, similarly to the marine vessel maneuvering system according to preferred embodiments of the present invention described above, the assist of the forward propulsive forces in the propulsion generators is terminated relatively smoothly, and thus good navigation stability of the marine vessel is maintained as compared with a case in which the temporarily generated propulsive force changes rapidly.

In a marine vessel according to a preferred embodiment of the present invention, the three or more marine propulsion units preferably include five marine propulsion units aligned in a right-left direction of the marine vessel, and the controller is preferably configured or programmed to perform the forward acceleration assist control to generate a forward propulsive force in the propulsion generator of one marine propulsion unit that is located at a center and is not used when the operator is operated to move the marine vessel diagonally forward among the five marine propulsion units. Accordingly, similarly to the marine vessel maneuvering system according to preferred embodiments of the present invention described above, in the large marine vessel including the five marine propulsion units, the acceleration at the time of moving the marine vessel forward is particularly small when the forward propulsive forces in the propulsion generators are not assisted, and thus the structure including the five marine propulsion units is effectively applied to a structure that improves the acceleration at the time of moving the marine vessel forward.

In a marine vessel according to a preferred embodiment of the present invention, the operator is preferably operable to receive an operation to move the marine vessel laterally in addition to the operations to move the marine vessel forward and diagonally forward, and the controller is preferably configured or programmed to perform the forward acceleration assist control to generate a forward propulsive force in the propulsion generator of a marine propulsion unit that is not used when the operator is operated to move the marine vessel diagonally forward and is operable to generate a backward propulsive force in the propulsion generator when the operator is operated to move the marine vessel laterally among the three or more marine propulsion units. Accordingly, similarly to the marine vessel maneuvering system according to preferred embodiments of the present invention described above, when the marine vessel is moved not only diagonally forward but also laterally, the right-left balance of the marine vessel is maintained. Furthermore, when the marine vessel is moved forward, the marine propulsion unit that is not used to maintain the right-left balance of the marine vessel when the marine vessel is moved diagonally forward and generates a backward propulsive force in the propulsion generator to maintain the balance of the marine vessel when the marine vessel is moved laterally is used as a marine propulsion unit that assists the forward propulsive forces in the propulsion generators.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Preferred embodiments of the present invention are hereinafter described with reference to the drawings.

The structure of a marine vessel maneuvering system110and the structure of a marine vessel100according to preferred embodiments of the present invention are now described with reference toFIGS.1to8. The marine vessel maneuvering system110maneuvers the marine vessel100. The marine vessel maneuvering system110is provided in the marine vessel100. In the figures, arrow FWD and arrow BWD represent the front side of and the rear side of the marine vessel100, respectively.

As shown inFIG.1, the marine vessel100includes a hull10and outboard motors20. The outboard motors20are attached to a rear transom of the hull10. Three or more outboard motors20(for example, five outboard motors20in a preferred embodiment of the present invention) are attached to the hull10. That is, the hull10is a relatively large (large mass) hull that requires the thrust of the five outboard motors20. The outboard motors20are examples of a “marine propulsion unit”.

The five outboard motors20include portside outboard motors20aand20blocated on the port side, starboard outboard motors20dand20elocated on the starboard side, and a central outboard motor20clocated between the portside outboard motor20band the starboard outboard motor20d. The five outboard motors20are aligned in the right-left direction of the marine vessel100. Specifically, the portside outboard motor20a, the portside outboard motor20b, the central outboard motor20c, the starboard outboard motor20d, and the starboard outboard motor20eare aligned in this order from the port side to the starboard side. The five outboard motors20are symmetrically aligned in the right-left direction of the marine vessel100with the central outboard motor20cas the center. The portside outboard motors20aand20bare examples of a “portside marine propulsion unit”. The starboard outboard motors20dand20eare examples of a “starboard marine propulsion unit”. The central outboard motor20cis an example of a “central marine propulsion unit”.

As shown inFIG.2, each of the five outboard motors20includes an engine21, a drive shaft22, a gearing23, a propeller shaft24, and a propeller25. The engine21is an internal combustion engine that generates a driving force. The driving force of the engine21is transmitted to the propeller25via the drive shaft22, the gearing23, and the propeller shaft24. The propeller25generates a thrust (a propulsive force to propel the marine vessel100) by rotating in the water by the driving force transmitted from the engine21. That is, in each of the five outboard motors20, the propeller25is driven by the engine21. The propeller25is an example of a “propulsion generator”.

As shown inFIG.3, each of the five outboard motors20includes a throttle actuator26. The throttle actuator26controls the throttle opening degree of the engine21(seeFIG.2). Thus, the rotation speed of the engine21that drives the propeller25is adjusted, and thus the propulsive force of the marine vessel100(seeFIG.1) is adjusted.

Each of the five outboard motors20includes a shift actuator27to switch the shift state. The shift actuator27switches between a forward movement state (shift-in state), a backward movement state (shift-in state), and a neutral state (shift-out state) by switching the meshing of the gearing23(seeFIG.2). In the forward movement state, a driving force is transmitted from the engine21(seeFIG.2) to the propeller25to generate a forward propulsive force in the propeller25(seeFIG.2). In the backward movement state, a driving force is transmitted from the engine21to the propeller25to generate a backward propulsive force in the propeller25. In the neutral state, a driving force is not transmitted from the engine21to the propeller25.

As shown inFIG.2, each of the five outboard motors20includes a steering28. Each of the outboard motors20is rotated in the right-left direction with respect to the hull10by the steering28. Thus, the orientation of the propeller25in the right-left direction is adjusted, and thus the direction of the propulsive force is adjusted to propel the hull10.

As shown inFIG.3, the hull10includes a remote control11, a steering wheel12, and a joystick13as operators that receive operations to maneuver the marine vessel100(seeFIG.1). The joystick13is an example of an “operator”.

The remote control11includes a lever that is operated such that the propulsive force of the propeller25(the rotation speed of the propeller25) is adjusted, and the shift state (the forward movement state, the backward movement state, or the neutral state) is switched. The steering wheel12is rotatable, and the steering wheel12is rotated such that the orientation of the propeller25is adjusted. Thus, an operation on the remote control11and an operation on the steering wheel12are combined such that the marine vessel100(seeFIG.1) is translated (moved forward, backward, laterally, or diagonally while the orientation of the hull10(seeFIG.1) is maintained) or is rotated, for example.

As shown inFIG.4, the joystick13includes a base13aand a lever13b. The lever13bis attached to the base13aso as to be tiltable and rotatable. The lever13bis urged by an urging member such as a spring to automatically return to a neutral position when not operated by a user. At the neutral position, the lever13bis upright and is not rotated.

Operations on the joystick13are roughly divided into three operations: an operation to tilt the lever13b, an operation to tilt and rotate the lever13b, and an operation to rotate the lever13b. The joystick13receives an operation to translate the marine vessel100(seeFIG.1) (move the marine vessel100forward, backward, laterally (rightward or leftward), or diagonally (diagonally forward or diagonally backward)), an operation to rotate the marine vessel100(right or left), and an operation to turn the marine vessel100(right or left).

The operation to tilt the lever13bcorresponds to an operation to translate the marine vessel100(seeFIG.1). That is, when the lever13bis tilted, the propulsive force (rotation speed) of the propeller25(seeFIG.2) is adjusted according to the amount of tilting of the lever13b, and the direction of the propulsive force (the forward movement state or the backward movement state) in the propeller25and the orientation of the propeller25are adjusted according to the tilting direction of the lever13b.

The operation to tilt and rotate the lever13bcorresponds to an operation to rotate the marine vessel100(seeFIG.1). That is, when the lever13bis tilted and rotated, the propulsive force (rotation speed) of the propeller25(seeFIG.2) is adjusted according to the amount of tilting of the lever13bsuch that the marine vessel100is rotated, and the direction of the propulsive force (the forward movement state or the backward movement state) in the propeller25and the orientation of the propeller25are adjusted according to the tilting direction, the rotational direction, and the amount of rotation of the lever13b.

The operation to rotate the lever13bcorresponds to an operation to turn the marine vessel100(seeFIG.1) (change the orientation of the hull10(seeFIG.1) on the spot). That is, when the lever13bis rotated, the propulsive force (rotation speed) of the propeller25(seeFIG.2) is adjusted according to the amount of rotation of the lever13bsuch that the marine vessel100is turned, and the orientation of the propeller25is adjusted according to the rotational direction of the lever13b. In the following description, for convenience of explanation, “the operation to tilt the lever13b” may be referred to as “the operation to tilt the joystick13”.

As shown inFIG.3, the hull10includes a first controller14, a second controller15, and a control switch16. The first controller14, the second controller15, and the control switch16include circuit boards including a central processing unit (CPU), a read-only memory (ROM), a random access memory (RAM), etc., for example. The second controller15is an example of a “controller”.

The first controller14controls the five outboard motors20based on operations on the remote control11and the steering wheel12. Specifically, the first controller14controls the throttle actuator26, the shift actuator27, and the steering28to adjust the propulsive force (rotation speed) of the propeller25of each of the five outboard motors20, switch the shift state of each of the five outboard motors20, and adjust the orientation of the propeller25of each of the five outboard motors20, respectively, based on the operations on the remote control11and the steering wheel12.

The second controller15controls the five outboard motors20based on an operation on the joystick13. Specifically, the second controller15controls the throttle actuator26, the shift actuator27, and the steering28to adjust the propulsive force (rotation speed) of the propeller25of each of the five outboard motors20, switch the shift state of each of the five outboard motors20, and the orientation of the propeller25of each of the five outboard motors20, respectively, based on the operation on the joystick13.

The control switch16switches between a state in which the first controller14controls the five outboard motors20and a state in which the second controller15controls the five outboard motors20. Specifically, as shown inFIG.4, a joystick mode switch13cis provided on the base13aof the joystick13. The joystick mode switch13cis pressed such that the control switch16switches between a state in which an operation on the joystick13is received but operations on the remote control11and the steering wheel12are not received (joystick mode) and a state in which an operation on the joystick13is not received but operations on the remote control11and the steering wheel12are received.

As described above, the hull10is a relatively large (large mass) hull, and thus acceleration at the time of moving the marine vessel100forward is relatively small (acceleration is relatively slow). Therefore, it is desired to improve the acceleration at the time of moving the marine vessel100forward by some method.

Therefore, as shown inFIG.5, in preferred embodiments of the present invention, the second controller15(seeFIG.3) performs a forward acceleration assist control to perform a control to generate a forward propulsive force in the propeller25(seeFIG.2) of the central outboard motor20cof the five outboard motors20when an operation to move the marine vessel100forward (an operation to tilt the joystick13forward) is performed on the joystick13(seeFIG.4). The central outboard motor20cis not used when the joystick13is operated to move the marine vessel100diagonally forward, and generates a backward propulsive force in the propeller25when the joystick13is operated to move the marine vessel100laterally. Even when an operation to move the marine vessel100forward is performed on the joystick13, the central outboard motor20cis not used unless conditions to perform the forward acceleration assist control described below are satisfied.

Specifically, as shown inFIG.6A, when the conditions to perform the forward acceleration assist control described below are not satisfied and the marine vessel100is moved forward (i.e., when the joystick13is tilted forward) (it may be hereinafter referred to as “when the marine vessel100is normally moved forward”), the five outboard motors20are controlled such that the central outboard motor20cis in the neutral state, and the portside outboard motors20aand20band the starboard outboard motors20dand20eare in the forward movement state. As shown inFIG.6B, when the marine vessel100is moved diagonally forward (i.e., when the joystick13is tilted diagonally forward to the right), the five outboard motors20are controlled such that the central outboard motor20cis in the neutral state, either the portside outboard motors20aand20bor the starboard outboard motors20dand20e(the portside outboard motors20aand20bin an example shown inFIG.6B) are in the forward movement state, and either the starboard outboard motors20dand20eor the portside outboard motors20aand20b(the starboard outboard motors20dand20ein the example shown inFIG.6B) are in the neutral state. As shown inFIG.6C, when the marine vessel100is moved laterally (i.e., when the joystick13is tilted to the right), the five outboard motors20are controlled such that either the portside outboard motors20aand20bor the starboard outboard motors20dand20e(the portside outboard motors20aand20bin an example shown inFIG.6C) are in the forward movement state, and either the starboard outboard motors20dand20eor the portside outboard motors20aand20b(the starboard outboard motors20dand20ein the example shown inFIG.6C) and the central outboard motor20care in the backward movement state.

That is, the central outboard motor20cis in the neutral state (i.e., no propulsive force is generated in the propeller25) when the marine vessel100is normally moved forward and when the marine vessel100is moved diagonally forward. When the marine vessel100is moved laterally, the central outboard motor20cis in the backward movement state (i.e., a backward propulsive force is generated in the propeller25).FIGS.6B and6Cshow examples in which diagonal forward movement and lateral movement are right diagonal forward movement and right movement, respectively, but when diagonal forward movement and lateral movement are left diagonal forward movement and left movement, respectively, the right and left sides are reversed with respect to the examples shown inFIGS.6B and6C.

As shown inFIGS.7and8, in a state (states ofFIGS.7B and7CandFIGS.8B and8C) between a state in which the marine vessel100is normally moved forward (states ofFIGS.7A and8A) and a state in which the marine vessel100is moved diagonally forward (states ofFIGS.7D and8D), the five outboard motors20are controlled such that the central outboard motor20cis in the neutral state, and both the portside outboard motors20aand20band the starboard outboard motors20dand20eare in the forward movement state. That is, in preferred embodiments of the present invention, the second controller15controls both the portside outboard motors20aand20band the starboard outboard motors20dand20eto move the marine vessel100forward without performing the forward acceleration assist control described below using the central outboard motor20cupon the joystick13being operated to move the marine vessel100forward when the marine vessel100is moved diagonally forward by either the portside outboard motors20aand20bor the starboard outboard motors20dand20e(seeFIG.7).FIG.7shows the states of the five outboard motors20when the state in which the marine vessel100is moved diagonally forward is changed to the state in which the marine vessel100is normally moved forward, andFIG.8shows the states of the five outboard motors20when the state in which the marine vessel100is normally moved forward is changed to the state in which the marine vessel100is moved diagonally forward.

Thus, any state between the state in which the marine vessel100is normally moved forward and the state in which the marine vessel100is moved diagonally forward is achieved by adjusting the balance between the propulsive forces of the portside outboard motors20aand20band the propulsive forces of the starboard outboard motors20dand20e. That is, the right-left balance of the marine vessel100is maintained by adjusting the balance between the propulsive forces of the portside outboard motors20aand20band the propulsive forces of the starboard outboard motors20dand20e. However, the central outboard motor20cis in the neutral state in many cases when an operation is performed to move the marine vessel100forward in order to maintain the right-left balance of the marine vessel100.

Therefore, as shown inFIGS.5A and5B, only when all the five outboard motors20are switched from the neutral state (i.e., a state in which the joystick13is at the neutral position) to a state in which all the five outboard motors20move the marine vessel100forward (i.e., a state in which the joystick13is tilted forward) (i.e., only under the conditions to perform the forward acceleration assist control), the five outboard motors20are controlled such that the central outboard motor20c, which is in the neutral state when the marine vessel100is normally moved forward and when the marine vessel100is moved diagonally forward, and is in the backward movement state when the marine vessel100is moved laterally, is set to the forward movement state and assists the propulsive forces of the portside outboard motors20aand20band the starboard outboard motors20dand20e, both of which are in the forward movement state. That is, in preferred embodiments of the present invention, the second controller15performs the forward acceleration assist control to move the marine vessel100forward with the central outboard motor20c, which is not used when the joystick13is operated to move the marine vessel100diagonally forward, in addition to both the portside outboard motors20aand20band the starboard outboard motors20dand20eupon the joystick13being operated to move the marine vessel100forward when the propulsive forces of the propellers25are previously not generated. When all of the outboard motors20are switched from the neutral state to the state in which all of the outboard motors20move the marine vessel100forward, the propulsive forces of the portside outboard motors20aand20band the propulsive forces of the starboard outboard motors20dand20eare evenly generated, and thus the right-left balance of the marine vessel100is unlikely to decrease.

In preferred embodiments of the present invention, the second controller15(seeFIG.3) performs the forward acceleration assist control to temporarily generate a forward propulsive force in the propeller25(seeFIG.2). Specifically, as shown inFIGS.5A and5B, the second controller15performs the forward acceleration assist control to gradually decrease the forward propulsive force temporarily generated in the propeller25in a predetermined second time (in a few seconds to a few tens of seconds, for example) until the forward propulsive force becomes zero after the forward propulsive force is maintained in a constant state (state ofFIG.5B) for a predetermined first time (for a few seconds, for example), as shown inFIGS.5B,5C, and5D. As shown inFIG.5B, the second controller15performs the forward acceleration assist control to gradually decrease the forward propulsive force of the propeller25(the propeller25of the central outboard motor20c) that temporarily generates the forward propulsive force until the forward propulsive force becomes zero after the forward propulsive force is maintained equal or substantially equal to the average of the forward propulsive forces of a plurality of remaining propellers25(the propellers25of the portside outboard motors20aand20band the starboard outboard motors20dand20e) for the first time.

According to the various preferred embodiments of the present invention described above, the following advantageous effects are achieved.

According to a preferred embodiment of the present invention, the second controller15is configured or programmed to, when the joystick13is operated to move the marine vessel100forward, perform a forward acceleration assist control to perform a control to generate a forward propulsive force in the propeller25of the outboard motor20that is not used when the joystick13is operated to move the marine vessel100diagonally forward. Accordingly, the propeller25of the outboard motor20that is not used when the joystick13is operated to move the marine vessel100diagonally forward assists the forward propulsive forces such that the acceleration of the marine vessel100at the time of moving the marine vessel100forward is improved. That is, the outboard motor20that is not used to maintain the right-left balance of the marine vessel100when the marine vessel100is moved diagonally forward is used as an outboard motor20that assists the forward propulsive forces in the propellers25. Furthermore, in the structure including three or more outboard motors20, some of the outboard motors20are not used at least to move the marine vessel100diagonally forward such that the right-left balance of the marine vessel100is maintained. Therefore, the acceleration at the time of moving the marine vessel100forward is improved while the right-left balance of the marine vessel100is maintained.

According to a preferred embodiment of the present invention, the three or more outboard motors20include the portside outboard motors20aand20blocated on the port side, the starboard outboard motors20dand20elocated on the starboard side, and the central outboard motor20clocated between the portside outboard motors20aand20band the starboard outboard motors20dand20e. Furthermore, the second controller15is configured or programmed to perform the forward acceleration assist control to generate a forward propulsive force in the propeller25of the central outboard motor20cthat is not used when the joystick13is operated to move the marine vessel100diagonally forward. Accordingly, the central outboard motor20cis not used to move the marine vessel100diagonally forward, but the portside outboard motors20aand20band the starboard outboard motors20dand20eare used, and thus at least when the marine vessel100is moved diagonally forward, the right-left balance of the marine vessel100is easily maintained.

According to a preferred embodiment of the present invention, the second controller15is configured or programmed to perform a forward acceleration assist control to temporarily generate a forward propulsive force in the propeller25. Accordingly, after the marine vessel100is accelerated in a forward movement direction and reaches a certain speed, the assist of the forward propulsive forces in the propellers25that is no longer needed is terminated.

According to a preferred embodiment of the present invention, the second controller15is configured or programmed to perform a forward acceleration assist control when the joystick13is tilted forward. Accordingly, a direction in which the joystick13is tilted and a direction in which the marine vessel100is moved match as a forward direction, and thus an operation is performed in an intuitively easy-to-understand state to perform the forward acceleration assist control. Furthermore, the joystick13is operated not only to move the marine vessel100forward but also to move the marine vessel100diagonally forward in an intuitively easy-to-understand state, and thus the joystick13is particularly effective as an “operator” in the structure in which the forward acceleration assist control is performed in connection with the operation to move the marine vessel100forward and the operation to move the marine vessel100diagonally forward.

According to a preferred embodiment of the present invention, the second controller15is configured or programmed to not perform a forward acceleration assist control upon the joystick13being operated to move the marine vessel100forward when the marine vessel100is previously moved diagonally forward. Furthermore, the second controller15is configured or programmed to perform a forward acceleration assist control upon the joystick being operated to move the marine vessel100forward when the propulsive forces of the propellers25are previously not generated. Accordingly, when some of the outboard motors20are not used such that it may be difficult to maintain the right-left balance of the marine vessel100, such as when the marine vessel100is switched from a diagonal forward movement state to a forward movement state, the forward propulsive forces in the propellers25are not assisted such that the difficulty in maintaining the right-left balance of the marine vessel100due to not using some of the outboard motors20is significantly reduced or prevented. Furthermore, when the assist of the forward propulsive forces in the propellers25is particularly needed, such as when a state in which the propulsive forces of the propellers25are not generated is switched to a state in which the marine vessel100is moved forward, the forward propulsive forces in the propellers25are effectively assisted.

According to a preferred embodiment of the present invention, the second controller15is configured or programmed to control both the portside outboard motors20aand20band the starboard outboard motors20dand20eto move the marine vessel100forward without performing the forward acceleration assist control using the central outboard motor20cupon the joystick13being operated to move the marine vessel100forward when the marine vessel100is moved diagonally forward by either the portside outboard motors20aand20bor the starboard outboard motors20dand20e. Furthermore, the second controller15is configured or programmed to perform a forward acceleration assist control to move the marine vessel100forward using the central outboard motor20c, which is not used when the joystick13is operated to move the marine vessel100diagonally forward, in addition to both the portside outboard motors20aand20band the starboard outboard motors20dand20eupon the joystick13being operated to move the marine vessel100forward when the propulsive forces of the propellers25are not generated. Accordingly, when some of the outboard motors20are not used such that it may be difficult to maintain the right-left balance of the marine vessel100, such as when the marine vessel100is switched from the diagonal forward movement state to the forward movement state, the forward propulsive forces in the propellers25are not assisted by the central outboard motor20cand both the portside outboard motors20aand20band the starboard outboard motors20dand20emove the marine vessel100forward such that the difficulty in maintaining the right-left balance of the marine vessel100due to not using some of the outboard motors20is easily significantly reduced or prevented. Furthermore, when the assist of the forward propulsive forces in the propellers25is particularly needed, such as when a state in which the propulsive forces of the propellers25are not generated is switched to a state in which the marine vessel100is moved forward, the central outboard motor20cis added to both the portside outboard motors20aand20band the starboard outboard motors20dand20esuch that the forward propulsive forces in the propellers25are assisted at the center of the marine vessel100in the right-left direction without decreasing the balance of the marine vessel100in the right-left direction.

According to a preferred embodiment of the present invention, the second controller15is configured or programmed to perform a forward acceleration assist control to gradually decrease a forward propulsive force temporarily generated in the propeller25until the forward propulsive force becomes zero. Accordingly, the assist of the forward propulsive forces in the propellers25is terminated relatively smoothly, and thus good navigation stability of the marine vessel100is maintained as compared with a case in which the temporarily generated propulsive force changes rapidly.

According to a preferred embodiment of the present invention, the second controller15is configured or programmed to perform a forward acceleration assist control to gradually decrease a forward propulsive force temporarily generated in the propeller25until the forward propulsive force becomes zero after the forward propulsive force is maintained in a constant state for the predetermined first time. Accordingly, the good navigation stability of the marine vessel100is maintained while the marine vessel100is sufficiently accelerated in the forward movement direction until the marine vessel100reaches a certain speed before the assist of the forward propulsive forces in the propellers25is terminated.

According to a preferred embodiment of the present invention, the second controller15is configured or programmed to perform a forward acceleration assist control to gradually decrease the forward propulsive force of the propeller25operable to temporarily generate the forward propulsive force until the forward propulsive force becomes zero after the forward propulsive force is maintained equal or substantially equal to the average of the forward propulsive forces of the plurality of remaining propellers25for the first time. Accordingly, the forward propulsive force temporarily generated in the propeller25is set to an appropriate magnitude in accordance with the average of the forward propulsive forces of the plurality of propellers25other than the propeller25that temporarily generates the forward propulsive force.

According to a preferred embodiment of the present invention, the propeller25of each of the three or more outboard motors20is driven by the engine21. Accordingly, in the structure including the three or more outboard motors20each including the propeller25driven by the engine21, some of the outboard motors20are not used at least to move the marine vessel100diagonally forward such that the acceleration at the time of moving the marine vessel100forward is improved while the right-left balance of the marine vessel100is maintained.

According to a preferred embodiment of the present invention, the marine vessel maneuvering system110(marine vessel100) includes the five outboard motors20aligned in the right-left direction of the marine vessel100. Furthermore, the second controller15is configured or programmed to perform the forward acceleration assist control to generate a forward propulsive force in the propeller25of one outboard motor20(central outboard motor20c) that is located at the center and is not used when the joystick13is operated to move the marine vessel100diagonally forward among the five outboard motors20. Accordingly, in the large marine vessel100including the five outboard motors20, the acceleration at the time of moving the marine vessel100forward is particularly small when the forward propulsive forces in the propellers25are not assisted, and thus the structure including the five outboard motors20is effectively applied to a structure that improves the acceleration at the time of moving the marine vessel100forward.

According to a preferred embodiment of the present invention, the joystick13is operable to receive an operation to move the marine vessel100laterally in addition to operations to move the marine vessel100forward and diagonally forward. Furthermore, the second controller15is configured or programmed to perform a forward acceleration assist control to generate a forward propulsive force in the propeller25of the outboard motor20that is not used when the joystick13is operated to move the marine vessel100diagonally forward and is operable to generate a backward propulsive force in the propeller25when the joystick13is operated to move the marine vessel100laterally. Accordingly, when the marine vessel100is moved not only diagonally forward but also laterally, the right-left balance of the marine vessel100is maintained. Furthermore, when the marine vessel100is moved forward, the outboard motor20that is not used to maintain the right-left balance of the marine vessel100when the marine vessel100is moved diagonally forward and generates a backward propulsive force in the propeller25to maintain the balance of the marine vessel100when the marine vessel100is moved laterally is used as an outboard motor20that assists the forward propulsive forces in the propellers25.

The preferred embodiments of the present invention described above are illustrative in all points and not restrictive. The extent of the present invention is not defined by the above description of the preferred embodiments but by the scope of the claims, and all modifications within the meaning and range equivalent to the scope of the claims are further included.

For example, while the second controller15(controller) is preferably configured or programmed to perform a forward acceleration assist control to generate a forward propulsive force in the propeller25(propulsion generator) of the outboard motor20(marine propulsion unit) that is not used when the joystick13(operator) is operated to move the marine vessel100diagonally forward and is operable to generate a backward propulsive force in the propeller25(propulsion generator) when the joystick13(operator) is operated to move the marine vessel100laterally in preferred embodiments described above, the present invention is not restricted to this. In the present invention, the controller may alternatively be configured or programmed to perform a forward acceleration assist control to generate a forward propulsive force in the propulsion generator of the marine propulsion unit that is not used when the operator is operated to move the marine vessel diagonally forward and is operable to not generate a backward propulsive force in the propulsion generator when the operator is operated to move the marine vessel laterally.

While a forward acceleration assist control is preferably performed in the marine vessel100including five outboard motors20(marine propulsion units) in preferred embodiments described above, the present invention is not restricted to this. In the present invention, for example, as in a first modified example shown inFIG.9, in a marine vessel200including a hull210and three outboard motors20(marine propulsion units), a forward acceleration assist control may alternatively be performed, as in a second modified example shown inFIG.10, in a marine vessel300including a hull310and four outboard motors20(marine propulsion units), a forward acceleration assist control may alternatively be performed, as in a third modified example shown inFIG.11, in a marine vessel400including a hull410and six outboard motors20(marine propulsion units), a forward acceleration assist control may alternatively be performed, or although not shown, in a marine vessel including seven or more marine propulsion units, a forward acceleration assist control may alternatively be performed.

While the propeller25(propulsion generator) of each of the three or more outboard motors20(marine propulsion units) is preferably driven by the engine21in preferred embodiments described above, the present invention is not restricted to this. In the present invention, the propulsion generator of each of the three or more marine propulsion units may alternatively be driven by an electric motor.

While the second controller15(controller) is preferably configured or programmed to perform a forward acceleration assist control to gradually decrease the forward propulsive force of the propeller25(propulsion generator) that temporarily generates the forward propulsive force until the forward propulsive force becomes zero after the forward propulsive force is maintained equal or substantially equal to the average of the forward propulsive forces of the plurality of remaining propellers25(propulsion generators) for the first time in preferred embodiments described above, the present invention is not restricted to this. In the present invention, the controller may alternatively be configured or programmed to perform a forward acceleration assist control to gradually decrease the forward propulsive force of the propulsion generator that temporarily generates the forward propulsive force until the forward propulsive force becomes zero after the forward propulsive force is maintained equal or substantially equal to a propulsive force other than the average of the forward propulsive forces of the plurality of remaining propulsion generators for the first time. Alternatively, the controller may be configured or programmed to perform a forward acceleration assist control to gradually decrease the temporarily generated forward propulsive force until the forward propulsive force becomes zero immediately without maintaining the temporarily generated forward propulsive force in a constant state. Alternatively, the controller may be configured or programmed to perform a forward acceleration assist control to immediately decrease the temporarily generated forward propulsive force until the forward propulsive force becomes zero.

While when the marine vessel100is moved forward or diagonally forward, for example, a set of two portside outboard motors20aand20b(portside marine propulsion units) is preferably used, and a set of two starboard outboard motors20dand20e(starboard marine propulsion units) is preferably used in preferred embodiments described above, the present invention is not restricted to this. In the present invention, as in a fourth modified example shown inFIG.12, only one of two portside marine propulsion units may alternatively be used, and only one of two starboard marine propulsion units may alternatively be used.

While the second controller15(controller) is preferably configured or programmed to not perform a forward acceleration assist control upon the joystick13(operator) being operated to move the marine vessel100forward when the marine vessel100is moved diagonally forward, and to perform a forward acceleration assist control upon the joystick13(operator) being operated to move the marine vessel100forward when the propulsive forces of the propellers25(propulsion generators) are not generated in preferred embodiments described above, the present invention is not restricted to this. In the present invention, the controller may alternatively be configured or programmed to perform a forward acceleration assist control upon the operator being operated to move the marine vessel forward when the marine vessel is moved diagonally forward, or to not perform a forward acceleration assist control upon the operator being operated to move the marine vessel forward when the propulsive forces of the propulsion generators are not generated.

While a joystick is preferably applied as an operator in preferred embodiments described above, the present invention is not restricted to this. In the present invention, any operator other than a joystick may alternatively be applied as an operator as long as the same receives at least operations to move the marine vessel forward and diagonally forward.

While outboard motors are preferably applied as marine propulsion units in preferred embodiments described above, the present invention is not restricted to this. In the present invention, inboard motors or inboard-outboard motors may alternatively be applied as marine propulsion units.