Jet propulsion systems and jet-propelled boats

Abstract

The present invention provides a jet propulsion system and a jet-propelled boat that enable the operator on board to immediately correct any unintended movement of the hull caused by radio control. [Solution] This jet propulsion system 100 comprises a jet propulsion mechanism 4, a jet water flow modification operation unit 6a that controls the movement of the hull 110 by changing at least one of the magnitude of the thrust force of the jet water flow, the left-right direction of the jet water flow, and the front-rear direction of the jet water flow, a wireless control device 2 that instructs the movement of the hull 110, and a control unit 8 that, when in wireless control mode, cancels wireless control mode and forcibly switches to manual control mode in which the hull 110 is moved by operation of the jet water flow modification operation unit 6a by the operator U1 based on the operation of the jet water flow modification operation unit 6a by the operator U1.

Description

Technical Field

[0001] This invention relates to a jet propulsion system and a jet-propelled boat.

Background Art

[0002] Conventionally, a jet-propelled boat equipped with a jet propulsion mechanism is known (for example, see Patent Document 1).

[0003] Patent Document 1 discloses a jet-propelled boat equipped with a jet propulsion mechanism. The jet-propelled boat is provided with a remote controller for remotely operating the jet-propelled boat.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the jet-propelled boat described in Patent Document 1, when the hull is remotely operated by a remote controller, there may be a case where the hull moves in an unintended manner by the remote operation by the remote controller while there is an operator on board the hull. For example, when the hull is remotely operated by a remote controller, the hull may move closer to an obstacle in front or move toward a restricted area. Therefore, when the operator on board the hull notices a situation where the hull is moving in an unintended manner by remote operation, it is required that the operator on board the hull himself / herself can immediately eliminate such a situation.

[0006] [[ID=I2]] This invention was made to solve the above-mentioned problems, and one of its objectives is to provide a jet propulsion system and a jet propulsion boat that can immediately correct, by the operator on board the vessel, when the movement of the vessel is being controlled wirelessly and is not intended by the operator on board. [Means for solving the problem]

[0007] To achieve the above objective, the jet propulsion system in the first aspect of this invention comprises: a jet propulsion mechanism located at the stern of the hull and including a nozzle provided with a jet water flow nozzle, which generates thrust by ejecting a jet water flow from the nozzle nozzle; a jet water flow modification operation unit which controls the movement of the hull by changing at least one of the magnitude of the thrust of the jet water flow ejected from the jet propulsion mechanism, the left-right direction of the jet water flow, and the front-rear direction of the jet water flow; a wireless control device which instructs the movement of the hull via wireless communication with the hull; and a control unit located on the hull which, when in wireless control mode in which the movement of the hull is instructed by the wireless control device, performs switching control to forcibly switch to manual control mode in which the hull is moved by the operator's operation of the jet water flow modification operation unit, based on the operation of the jet water flow modification operation unit by the operator on board the hull.

[0008] In the jet propulsion system according to the first aspect of this invention, as described above, the system includes a jet water flow modification control unit that controls the movement of the hull by changing at least one of the magnitude of the thrust of the jet water flow ejected from the jet propulsion mechanism, the left-right direction of the jet water flow, and the front-rear direction of the jet water flow, and a control unit provided on the hull that, when in wireless steering mode where the movement of the hull is instructed by a wireless control device, the system is configured to perform switching control that, based on the operation of the jet water flow modification control unit by the operator on board the hull, cancels the wireless steering mode and forcibly switches to manual steering mode in which the hull is moved by the operator's operation of the jet water flow modification control unit. As a result, the operator on board the hull can forcibly switch from wireless steering mode to manual steering mode by operating the jet water flow modification control unit, thereby ending the wireless steering mode and immediately starting manual steering mode in which the hull is moved by the operator's will. Therefore, if the ship's movement is being controlled by radio without the intention of the operator on board, the operator on board can immediately correct the situation themselves. In particular, if the operator on board notices a situation where the radio control mode should be terminated, such as the ship continuously moving towards an obstacle ahead, they can switch to manual control mode, which prioritizes the operator's intention and allows them to immediately move the ship.

[0009] In the jet propulsion system according to the first phase described above, preferably, a notification unit is further provided to notify that a switch has been forcibly made from wireless control mode to manual control mode when switching control is performed. With this configuration, the operator can easily recognize from the notification unit that a switch has been made from wireless control mode to manual control mode.

[0010] In the jet propulsion system according to the first aspect described above, preferably, the jet propulsion mechanism includes an impeller that generates a jet of water, the jet water flow modification unit includes a thrust force modification unit that increases or decreases the magnitude of the thrust force obtained by the jet water flow by increasing or decreasing the rotational speed of the impeller, and the control unit, when in wireless control mode, performs switching control that cancels wireless control mode and forcibly switches to manual control mode based on the operation of the thrust force modification unit by the operator. With this configuration, the system can be forcibly switched from wireless control mode to manual control mode, triggered by the operator attempting to accelerate the hull by operating the thrust force modification unit to avoid obstacles, etc.

[0011] In this case, preferably, the thrust change operation unit is a throttle lever that increases or decreases the rotation speed of the impeller according to the amount of operation, and the throttle lever is equipped with a lever position sensor that detects the amount of operation of the throttle lever, and the control unit, when in wireless operation mode, performs switching control that cancels wireless operation mode and forcibly switches to manual operation mode based on the lever position sensor detecting the operation of the throttle lever. With this configuration, the operator's attempt to accelerate the hull by operating the throttle lever can be used as a trigger to forcibly switch from wireless operation mode to manual operation mode.

[0012] In a configuration where the thrust change operation unit is a throttle lever equipped with a lever position sensor, preferably, the throttle lever has a forward throttle lever for moving the hull forward and a reverse throttle lever for moving the hull backward, and the lever position sensor has a forward lever position sensor for detecting the amount of operation of the forward throttle lever and a reverse lever position sensor for detecting the amount of operation of the reverse throttle lever, and the control unit, when in wireless operation mode, performs switching control to forcibly switch from wireless operation mode to manual operation mode based on whether the forward lever position sensor has detected operation of the forward throttle lever or the reverse lever position sensor has detected operation of the reverse throttle lever. With this configuration, the operator's attempt to accelerate the hull by operating the forward throttle lever or the reverse throttle lever can be used as a trigger to forcibly switch from wireless operation mode to manual operation mode.

[0013] In a configuration in which the jet water flow modification control unit includes a thrust force modification control unit, preferably, the control unit is configured to temporarily set an upper limit on the magnitude of the thrust force of the jet water flow ejected from the jet propulsion mechanism when the thrust force modification control unit is operated to perform switching control, thereby limiting the magnitude of the thrust force of the jet water flow. With this configuration, if the operator reflexively operates the thrust force modification control unit to rapidly increase the magnitude of the thrust force in order to avoid an obstacle or the like, it is possible to suppress the sudden acceleration of the hull.

[0014] In the configuration comprising the above-described notification unit, preferably, the notification unit includes a sound-emitting unit that emits a predetermined notification sound to indicate that the ship has been forcibly switched from wireless operation mode to manual operation mode when switching control is performed. With this configuration, even in cases of poor visibility or when the operator cannot take their eyes off the direction of travel, the operator can easily recognize by sound that the ship has been switched from wireless operation mode to manual operation mode by the sound-emitting unit.

[0015] In the configuration comprising the above-described notification unit, preferably, the notification unit includes a display unit that displays a predetermined notification indicating that the ship has been forcibly switched from wireless operation mode to manual operation mode when switching control is performed. With this configuration, even when the engine noise is loud, the operator can easily visually recognize from the display unit that the ship has been switched from wireless operation mode to manual operation mode.

[0016] In the jet propulsion system according to the first aspect described above, preferably, the jet water flow change operation unit includes a shift lever for switching between shifts, and the control unit, when in wireless operation mode, performs switching control to forcibly switch from wireless operation mode to manual operation mode based on the operator operating the shift lever to switch between forward and reverse movement of the hull. With this configuration, the system can be forcibly switched from wireless operation mode to manual operation mode by triggering a shift switching operation by the operator, such as switching from forward to reverse using the shift lever.

[0017] In the jet propulsion system according to the first aspect described above, preferably, the jet water flow modification control unit includes a steering control unit operated by the operator, and the steering control unit is equipped with a steering sensor that detects the amount of operation of the steering control unit. When the control unit is in wireless operation mode, it performs switching control to forcibly switch from wireless operation mode to manual operation mode based on the steering sensor detecting operation of the steering control unit. With this configuration, the operator can forcibly switch from wireless operation mode to manual operation mode by using a turning operation to the left or right of the steering control unit as a trigger for avoiding obstacles or the like.

[0018] In the jet propulsion system according to the first aspect described above, preferably, an electric motor is included, and in wireless operation mode, a steering actuator is further provided which rotates the nozzle in the left-right direction by the driving force of the electric motor to change the direction of the jet water flow from the nozzle in the left-right direction, and the control unit is configured to stop the supply of driving power to the electric motor by switching control, so that in manual operation mode, the operator can steer the hull by operating the jet water flow change operation unit. With this configuration, if steering operations are performed by the operator after the system has been forcibly switched from wireless operation mode to manual operation mode, no load can be placed on the electric motor.

[0019] In this case, preferably, the steering actuator further includes a steering control unit operated by the operator, and the steering actuator further includes a transmission gear that transmits the driving force of the electric motor and the steering control unit to the nozzle, a nozzle-side steering cable with one end connected to the transmission gear and the nozzle, respectively, for pushing and pulling the nozzle, and a control unit-side steering cable with one end connected to the transmission gear and the steering control unit, respectively, for pushing and pulling the nozzle. With this configuration, driving force can be transmitted from the steering control unit and the electric motor to the nozzle via a transmission gear and a nozzle-side steering cable, which are provided as a common configuration for the steering control unit and the electric motor. Therefore, the number of parts can be reduced and the device configuration can be simplified.

[0020] In the jet propulsion system according to the first aspect described above, preferably, the wireless operation mode includes a remote operation mode in which the hull is operated remotely using a wireless control device, and an automatic movement mode in which the hull is moved automatically by giving instructions to move the hull automatically from a remote location using the wireless control device. With this configuration, when in remote operation mode or automatic movement mode, the operator on board the hull can forcibly switch from remote operation mode or automatic movement mode to manual operation mode by operating the jet water flow change control unit, for example, to avoid an obstacle.

[0021] A jet-propelled boat in a second aspect of this invention comprises a hull; a jet propulsion mechanism located at the stern of the hull and including a nozzle provided with a jet stream nozzle, which generates thrust by ejecting a jet stream from the nozzle nozzle; a jet stream modification control unit which controls the movement of the hull by changing at least one of the magnitude of the thrust of the jet stream ejected from the jet propulsion mechanism, the left-right direction of the jet stream, and the front-rear direction of the jet stream; a wireless control device which instructs the movement of the hull via wireless communication with the hull; and a control unit located on the hull which, when in wireless control mode where the movement of the hull is instructed by the wireless control device, performs switching control to forcibly switch to manual control mode in which the hull is moved by the operator's operation of the jet stream modification control unit, based on the operation of the jet stream modification control unit by the operator on board the hull.

[0022] In a jet-propelled boat according to the second aspect of this invention, as described above, the boat includes a jet flow modification control unit that controls the movement of the hull by changing at least one of the magnitude of the thrust of the jet stream ejected from the jet propulsion mechanism, the left-right direction of the jet stream, and the front-rear direction of the jet stream, and a control unit provided on the hull that, when in wireless operation mode where the movement of the hull is instructed by a wireless control device, the control unit is configured to perform switching control that, based on the operation of the jet flow modification control unit by the operator on board the hull, cancels the wireless operation mode and forcibly switches to manual operation mode in which the hull is moved by the operator's operation of the jet flow modification control unit. As a result, the operator on board the hull can operate the jet flow modification control unit to forcibly switch from wireless operation mode to manual operation mode, thereby ending the wireless operation mode and immediately starting manual operation mode in which the hull is moved by the operator's will. Therefore, it is possible to provide a jet-propelled boat that allows the operator on board to immediately correct any unintended movement of the vessel being performed via radio control. In particular, if the operator on board notices a situation where the radio control mode should be terminated, such as moving towards an obstacle ahead, they can switch to manual control mode, thereby prioritizing the operator's will and immediately moving the vessel.

[0023] In the jet-powered boat according to the second phase described above, preferably, a notification unit is further provided to notify that a switch has been forcibly made from wireless control mode to manual control mode when switching control is performed. With this configuration, the operator can easily recognize from the notification unit that a switch has been made from wireless control mode to manual control mode.

[0024] In the jet boat according to the second aspect, preferably, the jet propulsion mechanism includes an impeller that generates a jet water flow, the jet water flow changing operation unit includes a propulsion force changing operation unit that increases or decreases the rotational speed of the impeller to increase or decrease the magnitude of the propulsion force obtained by the jet water flow, and the control unit, when in the wireless steering mode, performs switching control to cancel the wireless steering mode and forcibly switch to the manual steering mode based on the fact that the propulsion force changing operation unit has been operated by the operator. With this configuration, it is possible to forcibly switch from the wireless steering mode to the manual steering mode triggered by the operator operating the propulsion force changing operation unit to accelerate the hull for obstacle avoidance or the like.

[0025] In this case, preferably, the propulsion force changing operation unit is a throttle lever that increases or decreases the rotational speed of the impeller according to the operation amount, and the throttle lever is provided with a lever position sensor that detects the operation amount of the throttle lever. The control unit, when in the wireless steering mode, performs switching control to cancel the wireless steering mode and forcibly switch to the manual steering mode based on the fact that the lever position sensor has detected the operation of the throttle lever. With this configuration, it is possible to forcibly switch from the wireless steering mode to the manual steering mode triggered by the operator operating the throttle lever to accelerate the hull.

[0026] In the configuration where the propulsion force change operation unit is a throttle lever provided with a lever position sensor, preferably, the throttle lever has a forward throttle lever for advancing the hull and a reverse throttle lever for reversing the hull, and the lever position sensor has a forward lever position sensor for detecting the operation amount of the forward throttle lever and a reverse lever position sensor for detecting the operation amount of the reverse throttle lever. When in the wireless steering mode, the control unit performs switching control to cancel the wireless steering mode and forcibly switch to the manual steering mode based on the detection by the forward lever position sensor of the operation of the forward throttle lever or the detection by the reverse lever position sensor of the operation of the reverse throttle lever. With this configuration, it is possible to forcibly switch from the wireless steering mode to the manual steering mode triggered by the operator's attempt to accelerate the hull by operating the forward throttle lever or the reverse throttle lever.

[0027] In the configuration where the jet water flow change operation unit includes the propulsion force change operation unit, preferably, the control unit is configured to temporarily limit the magnitude of the propulsion force of the jet water flow ejected from the jet propulsion mechanism when the propulsion force change operation unit is operated to perform switching control. With this configuration, when the operator reflexively increases the magnitude of the propulsion force on the propulsion force change operation unit for obstacle avoidance or the like, it is possible to suppress the hull from accelerating rapidly.

[0028] In the configuration including the notification unit, preferably, the notification unit includes a sound emitting unit that emits a predetermined notification sound to notify that the switching control has been performed and the manual steering mode has been forcibly switched from the wireless steering mode. With this configuration, even when the visibility is poor or the operator cannot take their eyes off the traveling direction, the operator can easily recognize by voice that the manual steering mode has been switched from the wireless steering mode by the sound emitting unit.

Advantages of the Invention

[0029] According to the present invention, as described above, it is possible to provide a jet propulsion system and a jet propulsion boat that enable the operator on board to immediately correct, in the event that the movement of the hull is being performed by wireless control unintended by the operator on board the hull. [Brief explanation of the drawing]

[0030] [Figure 1] This is a side view showing a jet-propelled boat equipped with a jet propulsion system according to an embodiment. [Figure 2] This is a magnified side view showing a portion of a jet-powered boat equipped with a jet propulsion system according to an embodiment. [Figure 3] This is a block diagram of a jet propulsion system according to an embodiment. [Figure 4] This figure shows a jet-propelled boat according to an embodiment, and a wireless control device that communicates wirelessly with the jet-propelled boat. [Figure 5] This figure shows the display screen of a wireless control device for a jet propulsion system according to an embodiment. [Figure 6] This is a schematic plan view illustrating the lateral rotation of the nozzle of the jet propulsion mechanism of a jet propulsion system according to an embodiment. [Figure 7] This is a schematic side view illustrating the vertical rotation (trim) of the nozzle of a jet propulsion mechanism according to an embodiment. [Figure 8] This is a schematic side view illustrating the vertical rotation of the reverse bucket of a jet propulsion mechanism according to an embodiment. [Figure 9] This is a magnified view of part A in Figure 2. [Figure 10] This diagram shows the operating section according to the embodiment, viewed from the rear. [Figure 11] This is a schematic plan view illustrating switching control. [Figure 12] This is a flowchart of the control process for switching control according to the embodiment. [Modes for carrying out the invention]

[0031] Hereinafter, one embodiment of the present invention will be described based on the drawings.

[0032] (Embodiment) (Configuration of a jet-powered boat) A jet-propelled boat 100 according to one embodiment of the present invention will be described with reference to Figures 1 to 12.

[0033] The jet-powered boat 100 shown in Figures 1 and 2 is a personal watercraft, configured to be operated by a relatively small number of people. The jet-powered boat 100 is a so-called jet ski that glides across the water's surface. The jet-powered boat 100 comprises a hull 110 and a jet propulsion system 120 mounted on the hull 110. The hull 110 includes a hull 111 that forms the bottom of the boat, a deck 112 located above the hull 111, and seats 113 located in the center left and right of the deck 112.

[0034] (Configuration of a jet propulsion system) As shown in Figure 3, the jet propulsion system 120 comprises a communication unit 1, a wireless control device 2, a jet drive source 3, a jet propulsion mechanism 4 including a nozzle 44 (see Figure 1) for ejecting a jet of water, an actuator 5 for changing the direction of the jet of water, an operating unit 6, a notification unit 7, a control unit 8, and a GPS receiver 9. The actuator 5 includes a steering actuator 50 and a trim actuator 55 for driving the nozzle 44, and a reverse actuator 56 for driving the reverse bucket 45.

[0035] In each figure, the longitudinal direction of the jet-propelled boat 100 is indicated by the X direction, with the forward direction being indicated by the X1 direction (FRD) and the reverse direction being indicated by the X2 direction (BWD). In each figure, the lateral direction of the jet-propelled boat 100 is indicated by the Y direction. In each figure, the vertical direction is indicated by the Z direction, with the upward direction being indicated by the Z1 direction and the downward direction being indicated by the Z2 direction.

[0036] In this embodiment, the jet propulsion system 120 (control unit 8) is configured to perform switching control to forcibly switch to a manual operation mode in which the hull 110 is moved by the operator U1 (see Figure 11) operating the jet water flow change control unit 6a, based on the operation of the jet water flow change control unit 6a by the operator U1 (see Figure 11) who is on board the hull 110, when the system is in a wireless operation mode in which the movement of the hull 110 is instructed by the wireless control device 2. In short, when the system is in a wireless operation mode in which the jet propulsion boat 100 is being moved by instructions from the wireless control device 2, the control unit 8 immediately terminates the wireless operation mode if the operator U1 reflexively operates the jet water flow change control unit 6a, such as the throttle lever 61, for the purpose of avoiding an obstacle. Furthermore, the control unit 8 immediately starts the manual operation mode so that the reflexive operation becomes effective. Switching control is a control mechanism that prioritizes actions consciously performed by the operator U1, such as obstacle avoidance, over the movement of the hull 110 in wireless control mode. Details of switching control will be described later.

[0037] (Configuration of the communication unit and wireless control device) The communication unit 1 shown in Figure 3 is installed on the hull 110. The communication unit 1 is configured to establish wireless communication with the wireless control device 2. As an example, the communication unit 1 is configured to establish wireless communication with the wireless control device 2 using Bluetooth®. Note that the communication unit is not limited to Bluetooth and may be a wireless communication unit using other communication standards such as Wi-Fi®. As preparation before sailing by the jet-propelled boat 100, wireless communication between the wireless control device 2 and the communication unit 1 is established by the operator U1 (see Figure 4).

[0038] The wireless control device 2 is held by the operator U1 (see Figure 11) who is on board the hull 110 of the jet-powered boat 100, or by the wireless operator U2 (see Figure 11) who is not on board the hull 110. For example, the wireless control device 2 is a smartphone. However, the wireless control device is not limited to a smartphone; it may also be a dedicated communication device for wireless communication with the jet-powered boat, or a tablet device. The wireless control device 2 has a dedicated application installed for establishing communication with the jet-powered boat 100.

[0039] The wireless control device 2 is a device that instructs the movement of the hull 110 via wireless communication with the hull 110. There are two modes in the wireless operation mode in which the movement of the hull 110 is instructed by the wireless control device 2. The wireless operation mode includes the remote operation mode and the automatic movement mode.

[0040] The remote control mode is a mode in which the hull 110 is operated remotely using the wireless control device 2. The remote control mode is activated by selecting "Remote Control" on the mode switching button 21 in the upper left corner of the display screen 20 (see Figure 5) of the dedicated application for the wireless control device 2. If "Manual Control" is selected on the mode switching button 21, the mode switches to manual control mode, in which the operator U1 operates the steering control unit 60 to operate the boat themselves. In remote control mode, the jet-propelled boat 100 is moved freely by remote control using the hull control buttons 22 on the display screen 20 (forward (F) button, reverse (R) button, and left and right turn buttons in the center of the screen, etc.). The jet propulsion system 120 (control unit 8) of this embodiment can switch from wireless control mode to manual control mode by switching control even if "Manual Control" is not selected on the mode switching button 21.

[0041] The automatic movement mode is a mode in which the hull 110 is moved automatically by giving instructions to move the hull 110 from a remote location using the wireless control device 2. The automatic movement mode includes modes such as the auto-return, fixed-point holding, and launching support mentioned above.

[0042] (Configuration of the jet power source) As shown in Figure 1, the jet drive source 3 includes an engine 30, a crankshaft 31, and a coupling 32. The engine 30 is a multi-cylinder internal combustion engine. The crankshaft 31 is an output shaft for outputting torque generated in the engine 30. The crankshaft 31 extends rearward from the engine 30. The coupling 32 is provided at the rear end of the crankshaft 31 and connects and fixes the crankshaft 31 to the impeller shaft 41 of the jet propulsion mechanism 4.

[0043] (Configuration of the jet propulsion system) The jet propulsion mechanism 4 is configured to generate thrust by ejecting a jet of water from the nozzle 44a of the nozzle 44. The jet propulsion mechanism 4 comprises a water channel 40, an impeller shaft 41, an impeller 42 for generating a jet of water, a nozzle 43 fixed to the rear end of the water channel 40, a nozzle 44 drivably mounted relative to the nozzle 43, and a reverse bucket (reverse gate) 45.

[0044] The waterway 40 extends from the lower part of the hull 110 toward the stern 114. Water is drawn into the waterway 40 from the intake port 40a at the lower part of the hull 110. An impeller shaft 41 extending toward the rear is located in the waterway 40. The impeller 42 is fixed to the impeller shaft 41. The impeller 42 rotates integrally with the impeller shaft 41, generating a flow toward the rear. The impeller shaft 41 is connected to the crankshaft 31 via a coupling 32. Therefore, the rotational speed of the impeller 42 increases or decreases in accordance with the increase or decrease in the rotational speed of the engine 30.

[0045] The nozzle 43 shown in Figure 6 has the function of spraying water flowing through the waterway 40 toward the rear nozzle 44. The nozzle 44 is attached to the nozzle 43 from the rear. The nozzle 44 is located at the stern 114 of the hull 110. The nozzle 44 is provided with a jet water flow nozzle 44a. The nozzle 44 has the function of a deflector that changes the direction of the jet water flow sprayed from the nozzle 44a. In detail, the nozzle 44 is attached to the nozzle 43 so that it can rotate left and right around the central axis C1 of the vertical central axis 46 that extends in the vertical direction (the steering position can be adjusted around the vertical central axis 46). The central axis C1 is located at the left-right center of the nozzle 44. The nozzle 44 is rotated left and right by the steering actuator 50.

[0046] The nozzle 44 shown in Figure 7 is attached to the nozzle 43 so as to be able to rotate vertically around the central axis C2 of the left-right central axis 47 that extends horizontally (the trim position can be adjusted around the left-right central axis 47). The central axis C2 is located at the vertical center of the nozzle 44. The nozzle 44 is rotated vertically by the trim actuator 55. In this way, the rotation of the nozzle 44 in the vertical, horizontal, and vertical directions changes the direction of the jet stream ejected from the nozzle opening 44a.

[0047] The reverse bucket 45 shown in Figure 8 is configured to change the direction of the jet stream in the forward and backward directions. The reverse bucket 45 rotates between an upper position above the nozzle 44 and a rear position above the nozzle 44, and when it moves to the rear position above the nozzle 44, it covers the nozzle 44a from the rear, thereby guiding the jet stream forward and changing the direction of the jet stream forward. The reverse bucket 45 is configured to rotate vertically around the central axis C3 of the left and right central axes 48 that extend in the left and right directions. The reverse bucket 45 is rotated vertically by a reverse actuator 56. Depending on the position of the reverse bucket 45, the jet propulsion boat 100 can switch between a forward state, a reverse state, and a neutral state in which the forward thrust and reverse thrust are approximately equal. The jet-propelled boat 100 is in a reverse or neutral position when the reverse bucket 45 covers the nozzle 44a from the rear, and in a forward position when the reverse bucket 45 does not cover the nozzle 44a from the rear. The reverse bucket 45 is provided with substantially cylindrical ejection openings 45a on both the left and right sides, having a central axis that points diagonally forward to the right of the hull 110.

[0048] (Configuration of the steering actuator) Referring to Figures 2 and 9, the steering actuator 50 includes an electric motor 51 as a drive source, a transmission gear 52 that transmits the driving force of the electric motor 51 and the steering control unit 60 to the nozzle 44, a nozzle-side steering cable 53, and a control unit-side steering cable 54. In wireless steering mode, the steering actuator 50 is configured to rotate the nozzle 44 in the left-right direction using the driving force of the electric motor 51, thereby changing the direction of the jet water flow from the injection port 44a in the left-right direction. The steering actuator 50 can rotate the nozzle 44 in the left-right direction even when a jet water flow is not being injected.

[0049] The electric motor 51 is equipped with a motor shaft 51a, a transmission shaft 51b, and a clutch 51c that switches the connection state between the motor shaft 51a and the transmission shaft 51b. Note that jet-propelled boats do not need to have a clutch. A bevel gear 51d is provided on the side of the transmission shaft 51b opposite to the clutch 51c.

[0050] The transmission gear 52 includes a first gear 52a having a bevel gear portion 521 and a pinion portion 522 that mesh with the bevel gear 51d, and a second gear 52b consisting of a rack that meshes with the pinion portion 522. The nozzle-side steering cable 53 has one end connected to the transmission gear 52 and the nozzle 44, respectively, and is configured to push and pull the nozzle 44. The operating unit-side steering cable 54 has one end connected to the transmission gear 52 and the steering operating unit 60, respectively, and is configured to push and pull the nozzle 44 via the second gear 52b and the nozzle-side steering cable 53. The nozzle-side steering cable 53 and the operating unit-side steering cable 54 are configured as push-pull cables. The operating unit-side steering cable 54 is configured to also push and pull the steering operating unit 60 when the electric motor 51 is driven. In other words, when the electric motor 51 is driven, the steering control unit 60 will operate even without operation by the operator U1 (see Figure 11). The nozzle-side steering cable 53 is connected to the steering cable connection part 44b of the nozzle 44. The nozzle 44 rotates left and right by being pushed and pulled by the nozzle-side steering cable 53.

[0051] (Trim actuator configuration) The trim actuator 55 shown in Figure 7 includes an electric motor (not shown) as a drive source and a trim cable 55a that transmits the driving force of the electric motor to the nozzle 44. The trim actuator 55 is configured to rotate the nozzle 44 vertically using the driving force of the electric motor, thereby changing the direction of the water jet. The trim actuator 55 can rotate the nozzle 44 vertically even when the water jet is not being sprayed. The trim cable 55a is connected to the trim cable connection part 44c of the nozzle 44. The trim cable 55a is made of a push-pull cable. The trim actuator 55 is driven based on operations on the trim operation part 62.

[0052] (Configuration of the reverse actuator) The reverse actuator 56 shown in Figure 8 includes an electric motor (not shown) as a drive source and a reverse cable 56a that transmits the driving force of the electric motor to the reverse bucket 45. The reverse actuator 56 is configured to rotate the reverse bucket 45 vertically using the driving force of the electric motor, thereby changing the direction of the water jet in the front-rear direction. The reverse cable 56a is connected to the reverse cable connection part 45b of the reverse bucket 45. The reverse cable 56a is made of a push-pull cable.

[0053] (Configuration of the control panel) As shown in Figure 10, the control unit 6 is located on the hull 110. The control unit 6 includes a jet flow modification control unit 6a and a trim control unit 62. The jet flow modification control unit 6a is configured to control the movement of the hull 110 by changing at least one of the magnitude of the thrust force of the jet stream ejected from the jet propulsion mechanism 4, the lateral direction of the jet stream, and the longitudinal direction of the jet stream.

[0054] The jet water flow modification control unit 6a includes a thrust force modification control unit 6b that increases or decreases the magnitude of the thrust force obtained by the jet water flow by increasing or decreasing the rotational speed of the impeller 42, and a steering control unit 60 operated by the operator U1. The thrust force modification control unit 6b is a throttle lever 61 that increases or decreases the rotational speed of the impeller 42 according to the amount of operation.

[0055] The steering control section 60 consists of a pair of bar-shaped grip sections provided on the left and right sides of the hull 110. The driving force input from the operator U1 to the steering control section 60 is transmitted to the nozzle 44 via the steering cable 54 on the control section side, the transmission gear 52, and the steering cable 53 on the nozzle side, as shown in Figure 2. As a result, the nozzle 44 rotates in the left and right directions.

[0056] The steering control unit 60 is equipped with a steering sensor 60a that detects the amount of operation of the steering control unit 60. For example, the steering sensor 60a is a sensor that detects the load associated with the rotation when the steering control unit 60 is rotated. The steering sensor 60a detects a larger load the faster the steering control unit 60 is operated. The steering sensor 60a is configured to detect the load by converting the strain of the detection unit caused by the rotation of the steering control unit 60 into a load (force). When the detected value of the steering sensor 60a exceeds a predetermined threshold, the control unit 8 determines that the steering control unit 60 has been operated by the operator U1. The reason for considering a predetermined threshold is to prevent switching control from being performed if the steering control unit 60 is operated slightly unconsciously (i.e., if an error occurs that causes the detected value of the steering sensor 60a to fall below the predetermined threshold).

[0057] The throttle lever 61 shown in Figure 10 is configured to increase or decrease the rotational speed of the impeller 42 (the opening of the throttle valve of the engine 30) according to the amount of operation. The harder the throttle lever 61 is squeezed, the greater the amount of operation, and therefore the stronger the jet of water. The throttle lever 61 is equipped with a lever position sensor 63 that detects the amount of operation of the throttle lever 61.

[0058] In detail, the throttle lever 61 has a forward throttle lever 61a for moving the hull 110 forward and a reverse throttle lever 61b for moving the hull 110 backward. The forward throttle lever 61a is located along the right-side steering control unit 60. The reverse throttle lever 61b is located along the left-side steering control unit 60. The lever position sensor 63 also has a forward lever position sensor 63a for detecting the amount of movement of the forward throttle lever 61a and a reverse lever position sensor 63b for detecting the amount of movement of the reverse throttle lever 61b.

[0059] The trim operation unit 62 has a trim-up button and a trim-down button. When the trim-up button is pressed, the trim actuator 55 rotates the nozzle 44 upward. When the trim-down button is pressed, the trim actuator 55 rotates the nozzle 44 downward.

[0060] (Composition of the News Department) The notification unit 7 is configured to notify that a switch has been forcibly made from wireless operation mode to manual operation mode when a switching control is performed. The notification unit 7 includes a sound generation unit 70 and a display unit 71.

[0061] The sound-emitting unit 70 is configured to emit a predetermined notification sound when switching control is performed, to indicate that the ship has been forcibly switched from wireless operation mode to manual operation mode. For example, the predetermined notification sound is a buzzer sound. Alternatively, the predetermined notification sound may be an audio message stating, "The ship has been forcibly switched from wireless operation mode to manual operation mode." Also, for example, the sound-emitting unit 70 is configured with a speaker capable of playing music or other sounds.

[0062] The display unit 71 is configured to display a predetermined notification when switching control is performed, indicating that the ship has been forcibly switched from wireless operation mode to manual operation mode. For example, the predetermined notification display may read, "The ship has been forcibly switched from wireless operation mode to manual operation mode." Also, for example, the display unit 71 is configured with a display capable of showing speed and other information.

[0063] (Configuration of the control unit) The control unit 8 is located on the hull 110. As an example, the control unit 8 shown in Figure 1 includes an ECU (Engine Control Unit), an SCU (Shift Control Unit) that controls shift switching, an RCU (Remote Control Unit) that performs ship handling control in wireless operation mode, and a steering actuator control device that performs control to drive the steering actuator 50. The control unit may also be configured as a single control device. The control unit 8 is a computer that includes a CPU, ROM, and RAM.

[0064] As described above, the control unit 8 shown in Figure 1 is configured to perform switching control when the ship is in wireless operation mode, in which the movement of the hull 110 is instructed by the wireless control device 2, and the jet water flow change control unit 6a is operated by the operator U1 (Figure 11). Based on this, the control unit 8 cancels the wireless operation mode and forcibly switches to manual operation mode, in which the hull 110 is moved by the operator U1's operation of the jet water flow change control unit 6a.

[0065] When the control unit 8 is in wireless control mode, it performs switching control to forcibly switch to manual control mode by canceling wireless control mode based on the operator U1 operating the thrust force change operation unit 6b (throttle lever 61) of the jet water flow change operation unit 6a. More specifically, when the control unit 8 is in wireless control mode, it performs switching control to forcibly switch to manual control mode by canceling wireless control mode based on the lever position sensor 63 (see Figure 10) detecting the operation of the throttle lever 61.

[0066] More specifically, when in wireless steering mode, the control unit 8 performs switching control to forcibly switch to manual steering mode based on whether the forward lever position sensor 63a (see Figure 10) detects operation of the forward throttle lever 61a (see Figure 10), or whether the reverse lever position sensor 63b detects operation of the reverse throttle lever 61b.

[0067] Furthermore, the control unit 8 is configured to stop the supply of drive power to the electric motor 51 of the steering actuator 50 through switching control, enabling the operator U1 to steer the hull 110 using the jet water flow change operation unit 6a in manual steering mode. The control unit 8 is also configured to limit the magnitude of the thrust force of the jet water flow ejected from the jet propulsion mechanism 4 when the thrust force change operation unit 6b is operated to perform switching control, thereby setting a temporary (instantaneous) upper limit on the magnitude of the thrust force of the jet water flow. Specifically, if the upper limit of the rotational speed of the impeller 42 (engine 30) before switching control is the first rotational speed, the upper limit of the rotational speed of the impeller 42 (engine 30) immediately after switching control is limited to the second rotational speed, which is smaller than the first rotational speed. Due to this limitation, even if operator U1 reflexively grips the throttle lever 61 hard to avoid an obstacle, the jet propulsion boat 100 will not accelerate rapidly.

[0068] Furthermore, when in wireless steering mode, the control unit 8 performs switching control to forcibly switch to manual steering mode based on the steering sensor 60a detecting operation of the steering control unit 60, thereby canceling wireless steering mode.

[0069] Referring to Figure 11, a specific example of switching control will be explained. In the example shown in Figure 11, the operator U1 (passenger) is on board the jet-powered boat 100, and the hull 110 is being remotely controlled by the radio operator U2 using the radio control device 2, as indicated by the dashed line. In this state indicated by the dashed line, the jet-powered boat 100 is in radio control mode.

[0070] The state indicated by the dashed line represents a situation where the operator U1 has detected an obstacle O ahead, while the radio operator U2 is unaware of the obstacle O. Therefore, operator U1 operates the forward throttle lever 61a to avoid the obstacle O. As a result, in order to activate this operation of the forward throttle lever 61a, the control unit 8 performs a switching control that forcibly switches from radio control mode to manual control mode. This allows operator U1 to avoid the obstacle O by operating the forward throttle lever 61a.

[0071] (Flow of the control process for switching control) The control process flow for the switching control shown in Figure 12 will now be explained. The switching control is performed by the control unit 8. The following steps will be explained starting from a state in wireless operation mode where the movement of the hull 110 is instructed by the wireless control device 2.

[0072] In step S1, it is determined whether the jet water flow change control unit 6a has been operated. Specifically, it is determined whether the forward throttle lever 61a, the reverse throttle lever 61b, or the steering control unit 60 has been operated. Operation of the forward throttle lever 61a is determined using the forward lever position sensor 63a. Operation of the reverse throttle lever 61b is determined using the reverse lever position sensor 63b. Operation of the steering control unit 60 is determined using the steering sensor 60a. In detail, if the detected value of the steering sensor 60a is above a predetermined threshold, the control unit 8 determines that the steering control unit 60 has been operated by the operator U1. If it is determined that the jet water flow change control unit 6a has been operated, the process proceeds to step S2. If it is determined that the jet water flow change control unit 6a has not been operated, step S1 is repeated.

[0073] In step S2, the system switches from wireless control mode to manual control mode. In other words, a switching control is performed. As a result, the movement of the hull 110 cannot be controlled by the wireless control device 2. The system then proceeds to step S3.

[0074] In step S3, a temporary (instantaneous) upper limit is set on the magnitude of the thrust force of the jet water stream ejected from the jet propulsion mechanism 4. Then, the process proceeds to step S4.

[0075] In step S4, the supply of drive power to the electric motor 51 of the steering actuator 50 is stopped. Then, the process proceeds to the end.

[0076] (Effects of the embodiment) In this embodiment, the following effects can be obtained.

[0077] In this embodiment, as described above, the system includes a jet water flow modification control unit 6a that controls the movement of the hull 110 by changing at least one of the magnitude of the thrust force of the jet water flow ejected from the jet propulsion mechanism 4, the left-right direction of the jet water flow, and the front-rear direction of the jet water flow, and a control unit 8 provided on the hull 110 that, when in wireless operation mode in which the movement of the hull 110 is instructed by the wireless control device 2, performs switching control to forcibly switch to manual operation mode in which the hull 110 is moved by the operation of the jet water flow modification control unit 6a by the operator U1 on board the hull 110, based on the operation of the jet water flow modification control unit 6a by the operator U1. This allows the operator U1 on board the hull 110 to operate the jet water flow change control unit 6a to forcibly switch from wireless operation mode to manual operation mode, thereby ending the wireless operation mode and immediately starting manual operation mode in which the hull 110 is moved according to the operator U1's will. Therefore, if the hull 110 is being moved by wireless operation in a way that is not intended by the operator U1 on board the hull 110, the operator U1 on board the hull 110 can immediately resolve the situation themselves. In particular, if the operator U1 on board the hull 110 notices a situation where the wireless operation mode should be ended, such as moving towards an obstacle ahead, switching to manual operation mode allows the operator U1 to prioritize their will and immediately move the hull 110, making it effective.

[0078] In this embodiment, as described above, a notification unit 7 is further provided to notify the operator that a switch has been forcibly made from wireless operation mode to manual operation mode when the switching control is performed. This allows the operator to easily recognize that a switch has been made from wireless operation mode to manual operation mode by the notification unit 7.

[0079] In this embodiment, as described above, the jet propulsion mechanism 4 includes an impeller 42 that generates a jet of water, the jet water flow modification operation unit 6a includes a thrust force modification operation unit 6b that increases or decreases the magnitude of the thrust force obtained by the jet water flow by increasing or decreasing the rotational speed of the impeller 42, and the control unit 8, when in wireless operation mode, performs switching control that cancels wireless operation mode and forcibly switches to manual operation mode based on the operation of the thrust force modification operation unit 6b by the operator U1. This allows for a forced switch from wireless operation mode to manual operation mode, triggered by the operator U1 attempting to accelerate the hull 110 by operating the thrust force modification operation unit 6b to avoid obstacles, etc.

[0080] In this embodiment, as described above, the thrust change operation unit 6b is a throttle lever 61 that increases or decreases the rotation speed of the impeller 42 according to the amount of operation. The throttle lever 61 is equipped with a lever position sensor 63 that detects the amount of operation of the throttle lever 61. When the control unit 8 is in wireless operation mode, it performs switching control to forcibly switch from wireless operation mode to manual operation mode based on the lever position sensor 63 detecting the operation of the throttle lever 61. This allows for a forced switch from wireless operation mode to manual operation mode, triggered by the operator U1 attempting to accelerate the hull 110 by operating the throttle lever 61.

[0081] In this embodiment, as described above, the throttle lever 61 has a forward throttle lever 61a for moving the hull 110 forward and a reverse throttle lever 61b for moving the hull 110 backward. The lever position sensor 63 has a forward lever position sensor 63a for detecting the amount of operation of the forward throttle lever 61a and a reverse lever position sensor 63b for detecting the amount of operation of the reverse throttle lever 61b. When the control unit 8 is in wireless operation mode, it performs switching control to forcibly switch from wireless operation mode to manual operation mode based on whether the forward lever position sensor 63a has detected operation of the forward throttle lever 61a or the reverse lever position sensor 63b has detected operation of the reverse throttle lever 61b. This allows for a forced switch from wireless operation mode to manual operation mode, triggered by the operator U1 attempting to accelerate the hull 110 by operating the forward throttle lever 61a or the reverse throttle lever 61b.

[0082] In this embodiment, as described above, the control unit 8 is configured to temporarily set an upper limit on the magnitude of the thrust force of the jet water ejected from the jet propulsion mechanism 4 when the thrust force change operation unit 6b is operated to perform switching control, thereby limiting the magnitude of the thrust force of the jet water. This makes it possible to suppress the sudden acceleration of the hull 110 when the operator U1 reflexively operates the thrust force change operation unit 6b to rapidly increase the magnitude of the thrust force in order to avoid an obstacle or the like.

[0083] In this embodiment, as described above, the notification unit 7 includes a sound-emitting unit 70 that emits a predetermined notification sound to indicate that the ship has been forcibly switched from wireless operation mode to manual operation mode when switching control is performed. This allows the operator to easily recognize by sound that the ship has been switched from wireless operation mode to manual operation mode, even in situations where visibility is poor or the operator cannot take their eyes off the direction of travel.

[0084] In this embodiment, as described above, the notification unit 7 includes a display unit 71 that displays a predetermined notification indicating that the ship has been forcibly switched from wireless operation mode to manual operation mode when switching control is performed. As a result, even when the engine noise is loud, the operator can easily visually recognize from the display unit 71 that the ship has been switched from wireless operation mode to manual operation mode.

[0085] In this embodiment, as described above, the jet water flow change operation unit 6a includes a shift lever for switching between shifts, and the control unit 8, when in wireless operation mode, performs switching control to forcibly switch from wireless operation mode to manual operation mode based on the shift lever being operated by the operator U1 to switch the hull 110 between forward and reverse. This allows for a forced switch from wireless operation mode to manual operation mode triggered by the operator U1 performing a shift switching operation, such as switching from forward to reverse, on the shift lever.

[0086] In this embodiment, as described above, the jet water flow change operation unit 6a includes a steering operation unit 60 operated by the operator U1, and the steering operation unit 60 is equipped with a steering sensor 60a that detects the amount of operation of the steering operation unit 60. When the control unit 8 is in wireless operation mode, it performs switching control to forcibly switch from wireless operation mode to manual operation mode based on the steering sensor 60a detecting operation of the steering operation unit 60. This allows for a forced switch from wireless operation mode to manual operation mode, triggered by the operator U1 performing a left or right turning operation on the steering operation unit 60 for purposes such as avoiding obstacles.

[0087] In this embodiment, as described above, the system further includes a steering actuator 50 which includes an electric motor 51 and, in wireless operation mode, rotates the nozzle 44 in the left-right direction using the driving force of the electric motor 51 to change the direction of the jet water flow from the injection port 44a in the left-right direction. The control unit 8 is configured to stop the supply of driving power to the electric motor 51 by switching control, enabling the operator U1 to steer the hull 110 using the jet water flow change operation unit 6a in manual operation mode. This prevents the electric motor 51 from being overloaded when steering is performed by the operator U1 after the system has been forcibly switched from wireless operation mode to manual operation mode.

[0088] In this embodiment, as described above, the steering actuator 50 further includes a steering control unit 60 operated by the operator U1, and the steering actuator 50 further includes a transmission gear 52 that transmits the driving force of the electric motor 51 and the steering control unit 60 to the nozzle 44, a nozzle-side steering cable 53 with one end connected to the transmission gear 52 and the nozzle 44 respectively, which pushes and pulls the nozzle 44, and an operating unit-side steering cable 54 with one end connected to the transmission gear 52 and the steering control unit 60 respectively, which pushes and pulls the nozzle 44. As a result, driving force can be transmitted from the steering control unit 60 and the electric motor 51 to the nozzle 44 via the transmission gear 52 and the nozzle-side steering cable 53, which are provided as a common configuration for the steering control unit 60 and the electric motor 51. Therefore, the number of parts can be reduced and the device configuration can be simplified.

[0089] In this embodiment, as described above, the wireless operation mode includes a remote operation mode in which the hull 110 is operated remotely by the wireless control device 2, and an automatic movement mode in which the hull 110 is moved automatically by issuing an instruction to move the hull 110 automatically from the wireless control device 2. This allows the operator U1 on board the hull 110 to forcibly switch from the remote operation mode or automatic movement mode to the manual operation mode by operating the jet water flow change control unit 6a in order to avoid obstacles or for other reasons when in the remote operation mode or automatic movement mode.

[0090] (modified version) The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of the present invention is indicated by the claims rather than by the description of the embodiments above, and further includes all modifications (modifications) within the meaning and scope equivalent to the claims.

[0091] For example, in the above embodiment, an example was shown in which the jet-propelled boat was configured as a so-called jet ski, but the present invention is not limited to this. In the present invention, the jet-propelled boat may be configured as a so-called jet-propelled sports boat.

[0092] In the above embodiment, the jet drive source for rotating the impeller was shown to include an engine, but the present invention is not limited to this. In the present invention, the jet drive source for rotating the impeller may include an electric motor.

[0093] Furthermore, although the above embodiment shows an example in which the steering sensor is a sensor that detects the load associated with rotation when the steering control unit is rotated, the present invention is not limited to this. In the present invention, the steering sensor may be an acceleration sensor that detects the acceleration when the steering control unit is rotated.

[0094] Furthermore, although the above embodiment shows an example in which the jet water flow change operation unit includes a forward throttle lever and a reverse throttle lever, the present invention is not limited thereto. In the present invention, the jet water flow change operation unit may include a throttle lever that increases or decreases the rotational speed of the impeller (engine) without distinguishing between forward and reverse, and a shift lever that moves the reverse bucket to switch the shift. In this case, when the control unit is in wireless operation mode, it performs switching control to forcibly switch from wireless operation mode to manual operation mode based on the operator operating the shift lever to switch between forward and reverse movement of the hull. Also, similar to the above embodiment, when the control unit is in wireless operation mode, it performs switching control to forcibly switch from wireless operation mode to manual operation mode based on the operator operating the throttle lever. With the above configuration, the operator can forcibly switch from wireless operation mode to manual operation mode triggered by a shift switching operation such as the operator operating the shift lever to switch from forward to reverse.

[0095] Furthermore, although the above embodiment shows an example in which a wireless control device is operated by a wireless operator located remotely on the hull, the present invention is not limited to this. In the present invention, the wireless control device is located on the hull, and the ship's operator, who is on board the hull, may also be the wireless operator of the wireless control device.

[0096] Furthermore, while the above embodiment shows an example where the operation that triggers the switching control includes two operations: operation of the throttle lever and operation of the steering control unit, the present invention is not limited to this. In the present invention, the operation that triggers the switching control may be operation of the throttle lever alone. Alternatively, the operation that triggers the switching control may be operation of the steering control unit alone.

[0097] Furthermore, although the above embodiment shows an example in which the drive source of the steering actuator is an electric motor, the present invention is not limited to this. In the present invention, the drive source of the steering actuator may be a cylinder, a solenoid, or the like.

[0098] Furthermore, although the above embodiment shows an example in which the wireless operation mode includes a remote operation mode and an automatic movement mode, the present invention is not limited thereto. In the present invention, the wireless operation mode may include only one of the remote operation mode or the automatic movement mode.

[0099] Furthermore, in the above embodiment, an example was shown in which the notification unit includes a sound-emitting unit and a display unit as a configuration for notifying that switching control has been performed, but the present invention is not limited thereto. In the present invention, the notification unit may include a notification lamp that switches from an off state to an on (flashing) state when switching control is performed, as a configuration for notifying that switching control has been performed. Alternatively, the notification unit may include only one of the sound-emitting unit and the display unit.

[0100] Furthermore, in the above embodiment, for the sake of explanation, the processing operations of the control unit were described using a flow-driven flowchart that processes sequentially according to the processing flow, but the present invention is not limited thereto. In the present invention, the processing operations of the control unit may be performed by event-driven processing, which executes processing on an event-by-event basis. In this case, it may be performed as a completely event-driven system, or a combination of event-driven and flow-driven systems may be used. [Explanation of symbols]

[0101] 2 Wireless operation device 4. Jet propulsion system 6a Jet water flow change control unit 6b Propulsion change control unit 7 Hochi Department 8 Control Unit 42 Impeller 44 nozzles 44a injection port 50 Steering Actuator 51 Electric motor 52 Transmission gear 53 Nozzle-side steering cable 54 Steering cable on the control panel side 60 Steering control unit 60a Steering Sensor 61 Throttle Lever 61a Forward throttle lever 61b Reverse throttle lever 63 Lever position sensor 63a Forward lever position sensor 63b Reverse lever position sensor 70 Pronunciation Section 71 Display section 100 Jet-powered boats 110 hull 114 Stern 120 Jet Propulsion System U1 Operator

Claims

1. A jet propulsion mechanism is provided, which includes a nozzle located at the stern of the hull and equipped with a jet of water nozzle, and generates thrust by ejecting a jet of water from the nozzle's nozzle opening. A jet water flow modification operation unit controls the movement of the hull by changing at least one of the magnitude of the thrust force of the jet water flow ejected from the jet propulsion mechanism, the lateral direction of the jet water flow, and the longitudinal direction of the jet water flow. A wireless control device that instructs the movement of the hull via wireless communication with the hull, A jet propulsion system comprising: a control unit provided on the hull, configured to perform switching control to forcibly switch to a manual steering mode in which the hull is moved by the operator's operation of the jet water flow modification control unit, based on the operator's operation of the jet water flow modification control unit when the hull is in a wireless steering mode in which the movement of the hull is instructed by the wireless control device, wherein the wireless steering mode is in which the movement of the hull is instructed by the wireless control device, and the control unit provided on the hull.

2. The jet propulsion system according to claim 1, further comprising a notification unit that notifies that the system has been forcibly switched from the wireless operation mode to the manual operation mode when the aforementioned switching control is performed.

3. The jet propulsion mechanism includes an impeller that generates a jet of water. The jet water flow modification control unit includes a thrust force modification control unit that increases or decreases the magnitude of the thrust force obtained by the jet water flow by increasing or decreasing the rotation speed of the impeller. The jet propulsion system according to claim 1, wherein the control unit, when in the wireless control mode, performs the switching control to forcibly switch to the manual control mode based on the operation of the propulsion force change control unit by the operator, thereby canceling the wireless control mode.

4. The thrust change control unit is a throttle lever that increases or decreases the rotation speed of the impeller according to the amount of operation. The throttle lever is equipped with a lever position sensor that detects the amount of operation of the throttle lever. The jet propulsion system according to claim 3, wherein the control unit, when in the wireless operation mode, performs the switching control to forcibly switch to the manual operation mode based on the lever position sensor detecting the operation of the throttle lever, thereby canceling the wireless operation mode.

5. The throttle lever has a forward throttle lever for moving the hull forward and a reverse throttle lever for moving the hull backward. The lever position sensor includes a forward lever position sensor for detecting the amount of operation of the forward throttle lever and a reverse lever position sensor for detecting the amount of operation of the reverse throttle lever. The jet propulsion system according to claim 4, wherein the control unit, when in the wireless operation mode, performs the switching control to forcibly switch to the manual operation mode based on the forward lever position sensor detecting the operation of the forward throttle lever or the reverse lever position sensor detecting the operation of the reverse throttle lever, thereby canceling the wireless operation mode.

6. The jet propulsion system according to claim 1, wherein the control unit is configured to temporarily set an upper limit on the magnitude of the thrust force of the jet water stream ejected from the jet propulsion mechanism when performing the switching control, thereby limiting the magnitude of the thrust force of the jet water stream.

7. The jet propulsion system according to claim 2, wherein the notification unit includes a sound-emitting unit that emits a predetermined notification sound to indicate that the ship has been forcibly switched from the wireless operation mode to the manual operation mode when the switching control is performed.

8. The jet propulsion system according to claim 2, wherein the notification unit includes a display unit that displays a predetermined notification indicating that the ship has been forcibly switched from the wireless operation mode to the manual operation mode when the switching control is performed.

9. The jet water flow change operation unit includes a shift lever for switching between gears. The jet propulsion system according to claim 1, wherein the control unit, when in the wireless control mode, performs the switching control to forcibly switch to the manual control mode based on the operator operating the shift lever to switch the hull between forward and reverse.

10. The jet water flow modification control unit includes a steering control unit operated by the operator. The steering control unit is equipped with a steering sensor that detects the amount of steering control unit being operated. The jet propulsion system according to claim 1, wherein the control unit, when in the wireless steering mode, performs the switching control to forcibly switch to the manual steering mode based on the steering sensor detecting an operation of the steering control unit, thereby canceling the wireless steering mode.

11. The system further includes an electric motor and, in the wireless control mode, a steering actuator that rotates the nozzle in the left-right direction using the driving force of the electric motor to change the direction of the jet water flow from the nozzle in the left-right direction, The jet propulsion system according to claim 1, wherein the control unit is configured to stop supplying drive power to the electric motor by the switching control, thereby enabling the operator to steer the hull using the jet water flow change control unit in the manual steering mode.

12. The vessel further comprises a steering control unit operated by the aforementioned operator, The steering actuator is A transmission gear that transmits the driving force of the electric motor and the steering control unit to the nozzle, A nozzle-side steering cable, with one end and the other end connected to the transmission gear and the nozzle respectively, pushes and pulls the nozzle, The jet propulsion system according to claim 11, further comprising: an operating-side steering cable, one end of which is connected to the transmission gear and the steering operating unit, respectively, for pushing and pulling the nozzle.

13. The aforementioned wireless ship handling mode is, The aforementioned wireless control device enables a remote operation mode in which the hull is operated remotely from the hull, The jet propulsion system according to claim 1, comprising: an automatic movement mode in which the hull is automatically moved by issuing an instruction to move the hull automatically from a remote location using the wireless control device.

14. The hull and, A jet propulsion mechanism is provided, which includes a nozzle located at the stern of the hull and equipped with a jet of water nozzle, and generates thrust by ejecting a jet of water from the nozzle's nozzle opening. A jet water flow modification operation unit controls the movement of the hull by changing at least one of the magnitude of the thrust force of the jet water flow ejected from the jet propulsion mechanism, the lateral direction of the jet water flow, and the longitudinal direction of the jet water flow. A wireless control device that instructs the movement of the hull via wireless communication with the hull, A jet-propelled boat comprising a control unit provided on the hull, configured to perform switching control, which, when the boat is in a wireless operation mode in which the movement of the hull is instructed by the wireless control device, cancels the wireless operation mode and forcibly switches to a manual operation mode in which the hull is moved by the operator's operation of the jet water flow change control unit, based on the operator's operation of the jet water flow change control unit.

15. The jet-powered boat according to claim 14, further comprising a notification unit that notifies that the boat has been forcibly switched from the wireless operation mode to the manual operation mode when the aforementioned switching control is performed.

16. The jet propulsion mechanism includes an impeller that generates a jet of water. The jet water flow modification control unit includes a thrust force modification control unit that increases or decreases the magnitude of the thrust force obtained by the jet water flow by increasing or decreasing the rotation speed of the impeller. The jet-powered boat according to claim 14, wherein the control unit, when in the wireless control mode, performs the switching control to forcibly switch to the manual control mode based on the operation of the propulsion force change control unit by the operator, thereby canceling the wireless control mode.

17. The thrust change control unit is a throttle lever that increases or decreases the rotation speed of the impeller according to the amount of operation. The throttle lever is equipped with a lever position sensor that detects the amount of operation of the throttle lever. The jet-powered boat according to claim 16, wherein the control unit, when in the wireless operation mode, performs the switching control to forcibly switch to the manual operation mode based on the lever position sensor detecting the operation of the throttle lever, thereby canceling the wireless operation mode.

18. The throttle lever has a forward throttle lever for moving the hull forward and a reverse throttle lever for moving the hull backward. The lever position sensor includes a forward lever position sensor for detecting the amount of operation of the forward throttle lever and a reverse lever position sensor for detecting the amount of operation of the reverse throttle lever. The jet-powered boat according to claim 17, wherein the control unit, when in the wireless operation mode, performs the switching control to forcibly switch to the manual operation mode based on the forward lever position sensor detecting the operation of the forward throttle lever or the reverse lever position sensor detecting the operation of the reverse throttle lever, thereby canceling the wireless operation mode.

19. The jet-propelled boat according to claim 14, wherein the control unit is configured to temporarily set an upper limit on the magnitude of the thrust force of the jet water stream ejected from the jet propulsion mechanism when performing the switching control, thereby limiting the magnitude of the thrust force of the jet water stream.

20. The jet-powered boat according to claim 15, wherein the notification unit includes a sound-emitting unit that emits a predetermined notification sound to indicate that the boat has been forcibly switched from the wireless operation mode to the manual operation mode when the switching control is performed.

Images