PERSONAL WATERCRAFT

Abstract

A personal watercraft includes: a watercraft body including a boarding section on which a driver boards and a sub-boarding section on which a mounted object other than the driver is mounted; a mounted object overboard detection unit that detects that the mounted object has fallen overboard from the watercraft body; and a notification unit that performs notification control to notify the driver of the falling overboard through a specific control target when the mounted object overboard detection unit detects that the mounted object has fallen overboard.

Description

BACKGROUND

Technical Field

The present disclosure relates to a personal watercraft that planes on water.

Background Art

As a type of the personal watercraft, a personal watercraft on which a plurality of occupants including a driver can board is known. For example, US 2014/0030937 A1 discloses a three-seater personal watercraft on which two passengers can board in addition to the driver. The personal watercraft is sometimes used for planing in a state of being loaded with luggage.

Here, a passenger or luggage is collectively referred to as mounted object. Since the mounted object is mounted just behind the driver, there is a risk that the driver does not notice a change, if any, in the state of the mounted object.

SUMMARY

The present disclosure has been made in view of the above circumstance, and an object thereof is to provide a personal watercraft that can notify a driver of a state change of a mounted object.

In order to solve the above problem, a personal watercraft according to one aspect of the present disclosure includes: a watercraft body including a boarding section on which a driver boards and a sub-boarding section on which a mounted object other than the driver is mounted; a mounted object overboard detection unit that detects that the mounted object has fallen overboard from the watercraft body, and a notification unit that performs notification control to notify the driver of the falling overboard through a specific control target when the mounted object overboard detection unit detects that the mounted object has fallen overboard.

A personal watercraft according to another aspect of the present disclosure includes: a watercraft body including a boarding section on which a driver boards and a sub-boarding section on which a mounted object other than the driver is mounted; a determination unit that determines whether or not the mounted object has fallen overboard from the watercraft body based on presence or absence of the mounted object detected during a planing preparation period and presence or absence of the mounted object detected during subsequent planing; and a notification unit that performs notification control to notify the driver of the falling overboard through a specific control target when the determination unit determines that the mounted object has fallen overboard.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partially broken side view of a personal watercraft according to an embodiment of the present disclosure.

FIG. 2 is a plan view of the personal watercraft.

FIG. 3 is a schematic view presenting a structure of a stop switch in a simplified manner.

FIG. 4 is a functional block diagram illustrating a control system of the personal watercraft.

FIG. 5 is a flowchart illustrating content of control performed when a driver or a passenger falls overboard.

FIG. 6 is a view corresponding to FIG. 2 illustrating a modification of the embodiment.

DETAILED DESCRIPTION

Hereinafter, an embodiment of a personal watercraft according to the present disclosure will be described with reference to the drawings. Some of the drawings are given indications of front, rear, left, and right directions, and these directions coincide with directions viewed from the driver on the personal watercraft.

[Configuration of Personal Watercraft]

FIG. 1 is a partially broken side view of a personal watercraft 1 according to an embodiment of the present disclosure, and FIG. 2 is a plan view of the personal watercraft 1. The personal watercraft 1 is a straddle-type jet propulsion watercraft called a PWC that jets a water flow rearward and navigates in reaction to the water flow. The personal watercraft 1 includes a watercraft body 10, a power unit 2 that generates a propulsive force for moving the watercraft body 10 on water, and a controller 7 (FIG. 4) that controls the power unit 2.

The watercraft body 10 includes a hull 11 and a deck 12 that covers the hull 11. The hull 11 and the deck 12 are connected to each other over the entire circumference by a gunwale line 10G. A rear region of a bottom surface 11A of the hull 11 is provided with a water inlet port 36, and an impeller passage 37 extending rearward with the water inlet port 36 as an inlet is formed so as to penetrate a rear part of the hull 11 in the front-rear direction. The power unit 2 applies a propulsive force to the watercraft body 10 by injecting rearward, through the impeller passage 37, water taken in from the water inlet port 36.

The deck 12 includes a front hatch 17, a front bumper 18, and a boarding platform 19. The front hatch 17 covers an upper opening of a luggage storage space provided in a front part of the deck 12. The front bumper 18 covers the foremost part of the watercraft body 10. The boarding platform 19 is arranged at rear of a seat 14 described later so as to cover the hull 11 and is used, for example, when an occupant returns from the water to the watercraft body 10. The boarding platform 19 has a flat rear floor part 19a. The rear floor part 19a can also be used as luggage storage for placing luggage, for example. Such the rear floor part 19a corresponds to the “luggage storage” or the “sub-boarding section” in the present disclosure.

The deck 12 is provided with a handle 13, the seat 14, a display panel 15, and a pair of side mirrors 20. The handle 13 is a steering handle operated by a driver M1 for steering the personal watercraft 1. The seat 14 is a seat on which a plurality of occupants including the driver M1 are seated, and is disposed at a substantially central position in the front-rear direction and the left-right direction of the deck 12. The display panel 15 is disposed in front of the handle 13 and displays various types of information related to the navigation of the personal watercraft 1, such as a planing speed, a remaining amount of fuel, and an operation mode. The pair of side mirrors 20 are mirrors for rear visual recognition attached to both left and right sides of the display panel 15.

In the present embodiment, the seat 14 is a three-seater seat on which three occupants can be seated. That is, the seat 14 includes a driver seat 14A on which the driver M1 is seated, and a first passenger seat 14B and a second passenger seat 14C on which two passengers M2 are seated. The driver seat 14A, the first passenger seat 14B, and the second passenger seat 14C are arranged in this order from the front. Hereinafter, a passenger seated on the first passenger seat 14B on the front side is referred to as first passenger M2a, and a passenger seated on the second passenger seat 14C on the rear side is referred to as second passenger M2b. When the first passenger M2a and the second passenger M2b are referred to without distinction, they are simply referred to as passenger M2. The first passenger seat 14B and the second passenger seat 14C correspond to the “passenger seat” or the “sub-boarding section” in the present disclosure.

Here, in the straddle-type personal watercraft 1 as in the present embodiment, due to the influence of weather conditions, force majeure, or the like, there is a possibility that the mounted object on the watercraft body 10 greatly separates from the watercraft body 10, that is, falling overboard occurs. For example, there is a possibility that, as amounted object, an occupant other than the driver M1, that is, the passenger M2 falling overboard from the watercraft body 10. However, there is a possibility that such falling overboard of the passenger M2 is not noticed by the driver M1. Therefore, in the personal watercraft 1 of the present embodiment, measures are taken to notify the driver M1 of falling overboard of the passenger M2 when the falling overboard is detected. As a part of this, the watercraft body 10 of the personal watercraft 1 is provided with an alarm 16 (FIG. 4) that issues a warning sound when falling overboard of the passenger M2 is detected. In the present specification, falling overboard can be defined as separation of a mounted object such as the passenger M2 from the watercraft body 10 exceeding a predetermined distance.

As illustrated in mainly FIG. 2, the handle 13 is provided with an accelerator 21, a start switch 22, and a stop switch 23. The accelerator 21 is a grip that is twisted for operation to adjust the planing speed of the personal watercraft 1. The start switch 22 is a switch that is pressed for operation to start an engine 4. The stop switch 23 is a switch that is pressed for operation to stop the engine 4.

As illustrated in FIG. 1, the power unit 2 includes the engine 4, a jet pump 3 that is driven by the engine 4 to inject water, and a reverse bucket 5 disposed at an outlet of the jet pump 3.

The engine 4 is, for example, a water-cooled four-stroke multicylinder engine using gasoline as fuel, and is a drive source that generates a driving force for driving the jet pump 3. The engine 4 is accommodated in an engine room R formed inside the hull 11. The engine 4 includes a crankshaft 41 extending in the front-rear direction as an output shaft.

The jet pump 3 is a pump that generates a jet water flow injected rearward by pressurizing and accelerating the water taken into the impeller passage 37 from the water inlet port 36. The jet pump 3 includes a pump shaft 31, an impeller 32, a pump case 33, and a jet nozzle 34.

The pump shaft 31 is coaxially coupled to a rear end of the crankshaft 41. The impeller 32 is attached to a rear end part of the pump shaft 31. The driving force of the engine 4 is transmitted to the impeller 32 via the crankshaft 41 and the pump shaft 31 to rotate the impeller 32 about the axis. The impeller 32 generates a jet water flow by rotating.

The pump case 33 is a case interposed in the middle of the impeller passage 37. The pump case 33 is disposed at the rear of the impeller 32 and rotatably supports the rear end part of the pump shaft 31.

The jet nozzle 34 is a nozzle having an injection port 39 for jetting a jet water flow generated by the impeller 32, and is disposed at the rear of the pump case 33. The jet nozzle 34 has a tapered shape in which the passage cross-sectional area decreases rearward. The jet nozzle 34 is swingable left and right by being supported via a support shaft extending in the up-down direction. The jet nozzle 34 is linked to the handle 13 via a cable or the like so as to swing left and right in accordance with steering of the handle 13. Left-right swing of the jet nozzle 34 changes the jetting direction of the jet water flow from the injection port 39, thereby changing the traveling direction of the personal watercraft 1.

The rear end part of the impeller passage 37 is a tapered part 38 in which the passage cross-sectional area decreases rearward. A rear part of the tapered part 38 enters the jet nozzle 34. The water taken into the impeller passage 37 from the water inlet port 36 is sent to the tapered part 38 and the jet nozzle 34 while being pressurized and accelerated in accordance with rotation of the impeller 32, and is injected at a high speed from the outlet of the jet nozzle 34 having a narrowed passage cross-sectional area, that is, the injection port 39.

The reverse bucket 5 is swingable in the up-down direction by being supported by the jet nozzle 34 via a support shaft extending in the left-right direction. Specifically, the reverse bucket 5 is movable among a forward position illustrated in FIG. 1 in which the reverse bucket 5 is swung upward so as not to cover the injection port 39 of the jet nozzle 34, a reverse position in which the reverse bucket 5 is swung downward so as to cover the injection port 39 of the jet nozzle 34 from the rear, and a neutral position between the forward position and the reverse position. When the reverse bucket 5 is in the forward position (FIG. 1), the jet water flow from the injection port 39 is jetted rearward, so that a forward propulsive force is applied to the watercraft body 10 and the personal watercraft 1 moves forward. When the reverse bucket 5 is in the reverse position, the jet water flow from the injection port 39 is bent forward by the reverse bucket 5. Due to this, a rearward propulsive force is applied to the watercraft body 10, and the personal watercraft 1 moves rearward. When the reverse bucket 5 is in the neutral position, apart of the jet water flow is bent forward, so that the rearward propulsive force and the forward propulsive force are balanced to substantially stop the movement of the personal watercraft 1.

A shift motor 26 (FIG. 4) for swinging the reverse bucket 5 is disposed in the vicinity of the reverse bucket 5. The reverse bucket 5 is movable among the forward position, the reverse position, and the neutral position described above in accordance with driving by the shift motor 26. A shift lever 25 (FIG. 4) for changing the traveling direction of the personal watercraft 1 by switching the position of the reverse bucket 5 is disposed at the handle 13 or in its vicinity.

As illustrated in FIG. 1, in the personal watercraft 1 of the present embodiment, the driver M1 and the watercraft body 10 can be connected by a tether 51. The tether 51 is a cable-like body that connects the driver M1 and the watercraft body 10, and is used to detect falling overboard of the driver M1. While FIG. 1 illustrates an example in which the end part of the tether 51 is connected to a wrist of the driver M1, the end part of the tether 51 on the driver M1 side is only required to be connected to an appropriate position of the driver M1, and the connection destination is not limited to the wrist.

The tether 51 connects the driver M1 and the stop switch 23. FIG. 3 is a schematic view presenting the structure of the stop switch 23. As illustrated in the figure, the stop switch 23 includes a button 61, a body 62 that supports the button 61, and a contact point 63 built in the body 62. Between the button 61 and the body 62, a bifurcated clip 51a constituting an end part of the tether 51 opposite to the driver M1 is fitted. When the driver M1 falls overboard from the driver seat 14A, the clip 51a comes off from its fitting position, whereby the stop switch 23 is automatically activated. That is, when the clip 51a comes off, the button 61 moves to the body 62 side (left side in FIG. 3) by receiving the biasing force of a spring that biases the button 61, and the contact point 63 is released. In response to release of the contact point 63, driving of the engine 4 is stopped. As described above, the tether 51 has a function of activating the stop switch 23 in response to falling overboard of the driver M1, thereby stopping the engine 4. In other words, in the present embodiment, the combination of the tether 51 and the stop switch 23 constitutes a driver overboard detection unit that detects falling overboard of the driver M1.

The watercraft body 10 is attached with a receiver 28 (FIG. 4). The receiver 28 is equipment that receives radio waves transmitted from a first communication terminal 29a and a second communication terminal 29b. As illustrated in FIG. 1, the first communication terminal 29a is a terminal carried (worn) by the first passenger M2a, and the second communication terminal 29b is a terminal carried (worn) by the second passenger M2b. Hereinafter, when the first communication terminal 29a and the second communication terminal 29b are referred to without distinction, they are simply referred to as communication terminal 29.

The radio wave transmitted from the communication terminal 29 is a relatively weak radio wave that is recognized by the receiver 28 on the condition that the separation distance from the receiver 28 is equal to or less than a reference value. Specifically, the communication terminal 29 transmits a weak radio wave that can be recognized by the receiver 28 in a state where the passenger M2 is on the watercraft body 10 or in its vicinity. That is, in a state where the passenger M2 is on the watercraft body 10 or in its vicinity, the separation distance between the communication terminal 29 and the receiver 28 becomes equal to or less than the reference value, and the receiver 28 can recognize the radio wave from the communication terminal 29. On the other hand, when the passenger M2 separates from the watercraft body 10 exceeding a predetermined distance, the separation distance between the communication terminal 29 and the receiver 28 exceeds the reference value, and the receiver 28 can no longer recognize the radio wave from the communication terminal 29.

Thus, the communication state between the communication terminal 29 and the receiver 28 serves as an index for identifying the relative position of the passenger M2 with respect to the watercraft body 10. For example, when the radio wave from the communication terminal 29 is recognized by the receiver 28, it can be regarded that the first passenger M2a is present on the watercraft body 10 or in its vicinity. On the other hand, when the radio wave from the communication terminal 29 is no longer recognized by the receiver 28 thereafter, it can be regarded that the passenger M2 is greatly separated from the watercraft body 10 (that is, the passenger M2 falls overboard from the watercraft body 10). Therefore, in the present embodiment, the communication terminal 29 is used to determine boarding or falling overboard of the passenger M2 carrying the communication terminal 29.

In the present embodiment, the communication terminal 29 is a small terminal that transmits a radio wave of a prescribed frequency that can be identified by the receiver 28, for example, similarly to a non-contact type key called a smart key that has been frequently used in recent years as an automobile key. In this case, typically, the communication terminal 29 is carried by the passenger M2 by being stored in a storage such as a pocket provided in the clothing (clothes, life jacket, and the like) of the passenger M2. Alternatively, the communication terminal 29 can also be carried by the passenger M2 also by being fixed to the clothing of the passenger M2 via a holder such as a key holder.

[Control of Personal Watercraft]

FIG. 4 is a functional block diagram illustrating the control system of the personal watercraft 1. As illustrated in the figure, the controller 7 is electrically connected to the accelerator 21, the start switch 22, the stop switch 23, the shift lever 25, and the receiver 28, and receives various signals output from these elements. The controller 7 is electrically connected to the engine 4, the display panel 15, the alarm 16, and the shift motor 26, and outputs a control signal to these elements. Regarding control of the engine 4, the controller 7 controls output of the engine 4 and operation such as start/stop of the engine 4 by controlling elements such as a fuel injection valve and an ignition plug included in the engine 4.

The controller 7 is a control device including, as a main part, a microcomputer including a processor (CPU) that performs calculation, memories such as a ROM and a RAM, and various input/output buses. The controller 7 functionally includes a main control unit 71, a notification unit 72, and a determination unit 73. The main control unit 71 is a module that mainly performs control regarding planing operation of the personal watercraft 1. The notification unit 72 is a module that performs control (notification control) of notifying the driver M1 of falling overboard of the passenger M2. The determination unit 73 is a module that performs various determinations necessary for the control of the main control unit 71 and the notification unit 72.

Next, the content of the control performed by the controller 7 when the driver M1 or the passenger M2 falls overboard will be described with reference to the flowchart illustrated in FIG. 5. As a premise of applying the control illustrated in FIG. 1, in order to enable planing of the personal watercraft 1, the driver M1 fits the clip 51a of the tether 51 between the button 61 and the body 62 of the stop switch 23, and turns on the start switch 22 to start the engine 4. The control in FIG. 5 is started at the time point when the engine 4 is started in this way.

When the control in FIG. 5 is started, the determination unit 73 of the controller 7 performs recognition processing for the passenger M2 (step S1). That is, the determination unit 73 confirms the communication state between the first communication terminal 29a carried by the first passenger M2a and the receiver 28 on the watercraft body 10, and, when it is confirmed that the radio wave from the first communication terminal 29a is recognized by the receiver 28, recognizes that the first passenger M2a is on the watercraft body 10. The determination unit 73 confirms the communication state between the second communication terminal 29b carried by the second passenger M2b and the receiver 28 on the watercraft body 10, and, when it is confirmed that the radio wave from the second communication terminal 29b is recognized by the receiver 28, recognizes that the second passenger M2b is on the watercraft body 10. The recognition processing of the passenger M2 in step S1 is performed during the planing preparation period immediately after the start of the engine 4. Here, the planing preparation period is a period from the start of the engine 4 to the start of planing of the personal watercraft 1 by the operation of the accelerator 21.

Next, the determination unit 73 determines whether or not the driver M1 has fallen overboard (step S2). That is, the determination unit 73 confirms the state of the stop switch 23 based on the signal of the contact point 63 of the stop switch 23, and as a result, when it is confirmed that the stop switch 23 is switched to on, determines that the driver M1 has fallen overboard from the watercraft body 10 (driver seat 14A). The fact that the stop switch 23 is switched to on after the end of the planing preparation period described above means that the clip 51a of the tether 51 for the driver M1 has comes off from the stop switch 23. Therefore, at the time point when the stop switch 23 is switched to on, it can be determined that the driver M1 has fallen overboard.

If the determination is YES in step S2 and falling overboard of the driver M1 is confirmed, the main control unit 71 of the controller 7 stops the engine 4 (step S3). That is, the main control unit 71 stops the rotation of the engine 4 by cutting the fuel supply to the engine 4 or the like.

Next, the determination unit 73 determines whether or not the start switch 22 has been turned on (step S4).

If the determination is NO in step S4 and it is confirmed that the start switch 22 is not turned on, the main control unit 71 returns to step S3 and continues to stop the engine 4.

On the other hand, if the determination is YES in step S4 and it is confirmed that the start switch 22 is turned on, the main control unit 71 starts the engine 4 by restarting the fuel supply to the engine 4 or the like (step S5).

Next, control in a case where NO is determined in step S2, that is, in a case where the driver M1 does not fall overboard will be described. In this case, the determination unit 73 determines whether or not there has been recognition of boarding of the first passenger M2a in step S1, that is, whether or not a radio wave from the first communication terminal 29a has been recognized by the receiver 28 during the planing preparation period (step S7).

If the determination is YES in step S7 and it is confirmed that the first passenger M2a has already been on board, the determination unit 73 determines whether or not the first passenger M2a has fallen overboard (step S8). That is, the determination unit 73 confirms the communication state between the first communication terminal 29a and the receiver 28, and, when it is confirmed that the communication level has decreased to an extent that the radio wave from the first communication terminal 29a is no longer recognized by the receiver 28, determines that the first passenger M2a has fallen overboard from the watercraft body 10.

As described above, the radio wave from the first communication terminal 29a is a relatively weak radio wave that is recognized by the receiver 28 under the condition that the separation distance from the receiver 28 is equal to or less than a reference value, in other words, under the condition that the first passenger M2a is present on the watercraft body 10 or in its vicinity. For this reason, in step S8, the decrease in the communication level to the extent that the radio wave from the first communication terminal 29a is no longer recognized, that is, the interruption of the communication between the first communication terminal 29a and the receiver 28 means that the first passenger M2a has greatly separated from the watercraft body 10 to such an extent that it can be regarded that the first passenger M2a has fallen overboard. Therefore, when the communication between the first communication terminal 29a and the receiver 28 is interrupted, the determination unit 73 determines that the first passenger M2a has fallen overboard. Thus, in the present embodiment, the combination of the first communication terminal 29a, the receiver 28, and the determination unit 73 constitutes a first mounted object overboard detection unit that detects falling overboard of the first passenger M2a.

On the other hand, if the determination is NO in step S7 and it is confirmed that the first passenger M2a is not on board, the determination unit 73 determines whether or not there has been recognition in step S1 that the second passenger M2b is on board, that is, whether or not the radio wave from the second communication terminal 29b has been recognized by the receiver 28 during the planing preparation period (step S10).

If the determination is YES in step S10 and it is confirmed that the second passenger M2b has already been on board, the determination unit 73 determines whether or not the second passenger M2b has fallen overboard (step S11). That is, the determination unit 73 confirms the communication state between the second communication terminal 29b and the receiver 28, and, when it is confirmed that the communication level has decreased to an extent that the radio wave from the second communication terminal 29b is no longer recognized by the receiver 28, determines that the second passenger M2b has fallen overboard from the watercraft body 10.

In step S11, the decrease in the communication level to the extent that the radio wave from the second communication terminal 29b is no longer recognized, that is, the interruption of the communication between the second communication terminal 29b and the receiver 28 means that the second passenger M2b has greatly separated from the watercraft body 10 to such an extent that it can be regarded that the second passenger M2b has fallen overboard. Therefore, when communication between the second communication terminal 29b and the receiver 28 is interrupted, the determination unit 73 determines that the second passenger M2b has fallen overboard from the watercraft body 10. Thus, in the present embodiment, the combination of the second communication terminal 29b, the receiver 28, and the determination unit 73 constitutes a second mounted object overboard detection unit that detects falling overboard of the second passenger M2b.

As described above, in the present embodiment, when the radio wave from the communication terminal 29 is recognized by the receiver 28 during the planing preparation period, the determination unit 73 recognizes that the passenger M2 is on the watercraft body 10 (S1), and when communication between the communication terminal for the passenger recognized to be on board and the receiver 28 is interrupted during planing, the determination unit 73 determines that the passenger has fallen overboard (S8 and S11). In other words, the determination unit 73 determines whether or not the passenger M2 has fallen overboard based on the presence or absence of the passenger M2 detected during the planing preparation period and the presence or absence of the passenger M2 detected during the planing. Alternatively, the determination unit 73 determines, based on the communication state with the communication terminal 29, each of whether or not a condition (first condition) has been satisfied, the condition being that the passenger M2 has boarded on the watercraft body 10 during the planing preparation period, and whether or not a condition (second condition) has been satisfied, the condition being that the passenger M2 has been separated from the watercraft body 10 exceeding a predetermined distance during the planing, and when both of these two conditions are confirmed to be satisfied, determines that the passenger M2 has fallen overboard.

If the determination is YES in step S8 and the falling overboard of the first passenger M2a is confirmed, or if the determination is YES in step S11 and the falling overboard of the second passenger M2b is confirmed, the notification unit 72 of the controller 7 executes notification control, which is control for notifying the driver M1 of the falling overboard of the passenger M2. This notification control includes the following steps S13 to S15.

Step S13 is control for restricting the output of the engine 4, more specifically, control for lowering the maximum rotation speed (allowable rotation speed) of the engine 4 as compared with the normal time before the passenger M2 falls overboard. Step S14 is control for causing the display panel 15 to display a predetermined message indicating falling overboard of the passenger M2. Step S15 is control of activating the alarm 16 to issue a warning sound. By executing, as the notification control, the control in which steps S13 to S15 are combined, the notification unit 72 notifies the driver M1 that the passenger M2 has fallen overboard, that is, at least one of the first passenger M2a and the second passenger M2b has fallen overboard.

Next, the determination unit 73 determines whether or not the passenger M2 who has fallen overboard has returned to the watercraft body 10 (step S16). For example, when the passenger M2 who has fallen overboard is both the first passenger M2a and the second passenger M2b, the determination unit 73 determines whether or not the radio waves from first and second communication terminals 29a and 29b are recognized again by the receiver 28, that is, whether or not the communication between both communication terminals 29a and 29b and receiver 28 is restored. Then, at the time point when the restoration of the communication is confirmed, it is determined that both passengers M2a and M2b have returned to the watercraft body 10. On the other hand, when the passenger M2 who has fallen overboard is one of the first passenger M2a and the second passenger M2b, the determination unit 73 determines that the passenger who has fallen overboard returns to the watercraft body 10 at the time point when the communication between the corresponding communication terminal (29a or 29b) and the receiver 28 is restored.

If the determination is YES in step S16 and it is confirmed that the passenger M2 who has fallen overboard returns to the watercraft body 10, the notification unit 72 ends the above-described notification control (S13 to S15). Thereafter, the flow returns to step S2.

On the other hand, if the determination is NO in step S16 and it is confirmed that the return to the watercraft body 10 has not completed, the notification unit 72 returns to step S13 and continues the notification control.

Operations and Effects

As described above, since in the present embodiment, when falling overboard of the passenger M2 is detected, the notification control (S13 to S15) for notifying the driver M1 of the falling overboard is executed, it is possible to notify the driver M1 of the falling overboard of the passenger M2 by the notification control. As a result, for example, it is possible to urge the driver M1 to take an action such as directing the personal watercraft 1 to the point of falling overboard in order to collect the passenger M2.

Specifically, in the present embodiment, as a part of the notification control, the control to lower the maximum rotation speed of the engine 4 (S13), that is, output restriction of the engine 4 is performed, and therefore it is possible to cause the driver M1 to feel an abnormality through a change in the operation mode of the engine 4. This makes it possible to effectively notify the driver M1 of the falling overboard of the passenger M2 even in a situation where the driver M1 has difficulty in recognizing only by sound or display, for example, at the time of planing at a high speed.

In the present embodiment, since the side mirror 20 for rear visual recognition is attached to the watercraft body 10, the driver M1 who is notified of the falling overboard of the passenger M2 by the notification control can confirm the state of the passenger M2 who has fallen overboard without greatly moving the line of sight by visually recognizing the rear using the side mirror 20.

In the present embodiment, since the receiver 28 capable of receiving radio waves from the communication terminal 29 carried by the passenger M2 (first and second passengers M2a and M2b) is provided on the watercraft body 10, it is possible to appropriately determine falling overboard of the passenger M2 based on a change in the communication state between the communication terminal 29 and the receiver 28 caused by falling overboard of the passenger M2. Unlike a case where, for example, a seat pressure-sensitive sensor that reacts to the weight of the passenger M2 applied to the seat 14 is used, it is hardly affected by a posture change of the passenger M2, acceleration/deceleration of the watercraft, a posture change of the watercraft, or the like, and it is possible to reduce the possibility of erroneously determining falling overboard of the passenger M2.

In particular, in the present embodiment, since it is determined whether or not the passenger M2 has fallen overboard based on the communication state between the communication terminal 29 and the receiver 28 during the planing preparation period immediately after the start of the engine 4 and the communication state during the subsequent planing, it is possible to determine falling overboard of only the passenger M2 who has been recognized to be on board before the planing, and to reduce the possibility of erroneously determining the falling overboard. That is, in a case where the boarding of the first passenger M2a is confirmed by the communication with the first communication terminal 29a during the planing preparation period, the falling overboard of the first passenger M2a is determined based on the subsequent change in the communication state with the first communication terminal 29a (S8). On the other hand, in a case where the boarding of the first passenger M2a is not confirmed during the planing preparation period, the falling overboard of the first passenger M2a is not determined thereafter. Similarly, in a case where the boarding of the second passenger M2b is confirmed by the communication with the second communication terminal 29b during the planing preparation period, the falling overboard of the second passenger M2b is determined based on the subsequent change in the communication state with the second communication terminal 29b (S11). On the other hand, in a case where the boarding of the second passenger M2b is not confirmed during the planing preparation period, the falling overboard of the second passenger M2b is not determined thereafter. Thus, since the falling overboard determination is performed only for the passenger M2 who is onboard before planing, the falling overboard of a passenger who is not onboard is not erroneously determined, and the determination accuracy can be stabilized.

In the present embodiment, since the engine 4 is stopped when falling overboard of the driver M1 is detected (S3), it is possible to facilitate return of the driver M1 to the personal watercraft 1. That is, when the engine 4 stops due to the falling overboard of the driver M1, the movement of the watercraft body 10 is restricted. As a result, the personal watercraft 1 can be kept in the vicinity of the point of falling overboard of the driver M1. This makes it possible to facilitate the action that the driver M1 having fallen overboard returns to the personal watercraft 1.

On the other hand, when not the driver M1 but the passenger M2 falls overboard, as described above, the output of the engine 4 is only restricted, and the operation itself of the engine 4 is continued. Therefore, the driver M1 can cause the personal watercraft 1 to direct to the point of falling overboard of the passenger M2 without any trouble, and can promptly collect the passenger M2 who has fallen overboard.

In the present embodiment, since the driver M1 and the stop switch 23 can be connected via the tether 51, and when the driver M1 falls overboard, the end part (clip 51a) of the tether 51 comes off from the stop switch 23, the stop switch 23 is automatically turned on and the engine 4 is stopped. Therefore, the engine 4 can be accurately stopped when the driver M1 falls overboard.

Modifications

In the above embodiment, as a part of the notification control for notifying falling overboard of the passenger M2, the control for lowering the maximum rotation speed of the engine 4, that is, the control for restricting the output of the engine 4 (S13) is performed, but the method of notification using the engine 4 is not limited to this. For example, the rotation speed of the engine 4 may be decreased by a predetermined decrease amount with respect to the rotation speed at the time of detection of falling overboard of the passenger M2. Alternatively, the engine 4 may be controlled such that the planing speed of the watercraft decreases by a predetermined decrease amount with respect to the speed at the time of detection of falling overboard. Any of these controls makes it possible to cause the driver M1 to feel speed decrease, and possible to cause the driver M1 to notice the falling overboard of the passenger M2 through the feeling. The decrease amount of the rotation speed or the planing speed in each control is preferably set to such an amount that the driver can feel a change in inertial force and does not generate excessive braking force.

As another method of the notification using the engine 4, the rotation speed of the engine 4 may be forcibly decreased to the idling rotation speed or its vicinity for a predetermined period from the time of detection of the falling overboard of the passenger M2. In any case, when the falling overboard of the passenger M2 is detected, the engine 4 is only required to be operated in a control mode (special mode) that generates special behavior different from that before detection of the falling overboard within a range where there is no great influence on traveling and the driver M1 can feel, and the specific content of the special mode can be appropriately changed.

In the above embodiment, at the time of the notification control for notifying falling overboard of the passenger M2, in addition to the control for restricting the output of engine 4, the control for issuing a warning sound from the alarm 16 and the control for displaying a predetermined message on the display panel 15 are performed. However, the method of the notification using a device other than engine 4 is not limited to this. For example, a vibrator that vibrates a component in contact with the driver M1 such as the handle 13 and the seat 14 may be provided, and the notification may be performed using the vibrator. Alternatively, some kind of display indicating falling overboard may be performed at an appropriate place visible to the driver M1 other than the display panel 15. As compared with a notification method using a warning sound, such a notification method using vibration or display has an advantage of being easily conveyed to the driver M1 even in a situation where water spray or engine sound is large.

In the above embodiment, the same notification control (S13 to S15) is executed regardless of which of the two passengers M2 (first passenger M2a and second passenger M2b) has fallen overboard. However, the notification aspect may be changed depending on which passenger has fallen overboard. That is, in the personal watercraft on which a plurality of passengers can be on board, falling overboard of each passenger may be notified separately or may be notified without distinction.

In the above embodiment, the output of the engine 4 is restricted as a part of the notification control, but such restriction of the engine output is not essential. That is, the present disclosure also includes an aspect of notifying a driver of falling overboard only by a method other than output restriction of the engine.

As a notification method similar to output restriction of the engine, control of changing the angle of the reverse bucket 5 may be performed so that the planing speed of the personal watercraft 1 decreases. Such angle change control of the reverse bucket 5 may be performed instead of output restriction of the engine 4, or may be performed in parallel with output restriction of the engine 4. Furthermore, a mechanism for applying a braking force to the watercraft body 10 may be separately prepared, and control for decreasing the planing speed by the braking force applied from the mechanism may be performed instead of or in addition to the output restriction of the engine 4. Any of these methods makes it possible to notify in an intuitive manner the driver of falling overboard through a behavior change of the watercraft body. When the reverse bucket 5 is not used at the time of the notification control, the reverse bucket 5 is not essential and may be omitted.

In the above embodiment, the period from the start of the engine 4 to the start of the planing of the personal watercraft 1 by the operation of the accelerator 21 is defined as the planing preparation period, and when the radio wave from the communication terminal 29 is recognized by the receiver 28 during the planing preparation period, it is determined that the passengers M2 and M3 have boarded the watercraft body 10. However, the period for performing the boarding determination of the passengers M2 and M3 is not limited to this. For example, a period from the start of the engine 4 to the elapse of a predetermined time may be set as the planing preparation period, or a period in which the planing speed is in a slow state of less than a predetermined threshold may be set as the planing preparation period. Alternatively, the time point when the power switch for turning on the power of the electrical components of the personal watercraft 1 is turned on may be the start of the planing preparation period.

In the above embodiment, on the premise that the communication terminal 29 carried by the passenger M2 is a terminal that transmits a relatively weak radio wave as recognized by the receiver 28 under the condition that the passenger M2 exists on the watercraft body 10 or in its vicinity, it is determined that the passenger M2 has fallen overboard from the watercraft body 10 when the communication level is decreased to an extent that the radio wave from the communication terminal 29 is not recognized by the receiver 28. However, the communication terminal 29 may transmit a relatively strong radio wave that can be recognized even when the passenger M2 falls overboard. In this case, for example, when the intensity of the radio wave received by the receiver 28 decreases over a predetermined level, it can be determined that the passenger M2 has fallen overboard from the watercraft body 10. In any case, the communication terminal 29 carried by the passenger M2 is only required to emit a signal that allows the presence or absence of falling overboard to be determined based on the communication state with the receiver 28, and various communication terminals can be used as long as it is possible.

In the above embodiment, a small terminal stored in a pocket or the like or attached to a key holder or the like, that is, a terminal similar to an automobile smart key or the like is used as the communication terminal 29. However, the communication terminal 29 is only required to be carried (worn) by the passenger M2 in an aspect of being movable together with the passenger M2, and a method of carrying the communication terminal is not particularly limited. For example, the communication terminal may be a terminal such as a wristwatch, that is, a terminal that can be wound around a wrist, an ankle, or the like of the passenger M2.

In the above embodiment, falling overboard of the passenger M2 is detected based on the communication state between the communication terminal 29 carried by the passenger M2 and the receiver 28 on the watercraft body 10, but the configuration of the means (passenger overboard detection unit) for detecting falling overboard of the passenger M2 is not limited to this. For example, a sensor that detects, based on the weight applied from the passenger M2, or optically detects the presence of the passenger M2 at a prescribed boarding position on the watercraft body 10, that is, at a position corresponding to the passenger seat (first and second passenger seats 14B and 14C) may be prepared, and falling overboard of the passenger M2 may be detected by means including the sensor. Alternatively, falling overboard of the passenger M2 may be detected using a contact type sensor or the like.

In the above embodiment, the falling overboard of the driver M1 is detected using the tether 51 attached to the driver M1 and the stop switch 23 to which the clip 51a of the tether 51 is fitted, but the configuration of the means (driver overboard detection unit) for detecting falling overboard of the driver M1 is not limited to this. For example, falling overboard of the driver M1 may be detected based on the communication state with the communication terminal similarly to detection of falling overboard of the passenger M2. Alternatively, falling overboard of the driver M1 may be detected using a sensor that detects, based on the weight, or optically detects the presence of the driver M1.

In the above embodiment, the engine 4 is stopped when falling overboard of the driver M1 is detected. However, the power unit 2 including the engine 4 is only required to be controlled so that the movement of the watercraft body 10 is restricted as compared with that before the detection of falling overboard of the driver M1, and it is not essential to stop the engine 4. For example, by changing the position of the reverse bucket 5 of the power unit 2 to the neutral position, the movement of the watercraft body 10 may be restricted while continuing the operation of the engine 4. Alternatively, the movement of the watercraft body 10 may be restricted by lowering the rotation speed of the engine 4 to the idling rotation speed or its vicinity. In a case where the output of the engine 4 is restricted when the driver M1 falls overboard, the operation mode is desirably a mode in which the movement of the watercraft body 10 is further restricted, unlike the operation mode of the engine 4 set when the passenger M2 falls overboard.

Furthermore, when the driver M1 falls overboard, the power unit 2 may be controlled such that the watercraft body 10 remains in an area where the distance from the point of falling overboard of the driver M1 to the watercraft body 10 is equal to or less than a predetermined value. For example, it is conceivable that the distance from the position of the watercraft body 10 at the time when the falling overboard of the driver M1 is detected to the current position of the watercraft body 10 is specified using a GPS function or the like, and the output of the engine 4 or the position of the reverse bucket 5 is controlled so that the distance becomes equal to or less than a predetermined value.

In the above embodiment, the falling overboard of the passenger M2 is detected and notified to the driver M1, but the event to be notified to the driver M1 is not limited to the falling overboard of the passenger M2. For example, it is also possible to notify the driver M1 of falling overboard of the luggage loaded on the watercraft body 10. FIG. 6 illustrates an example in which the communication terminal 29 is mounted to luggage P in order to notify the driver M1 of falling overboard of the luggage P loaded on the rear floor part 19a (luggage storage). The communication terminal 29 can be stored in an appropriate storage included in the luggage P. or can be fixed to the luggage P via a holding tool such as a key holder. When the luggage P falls overboard from the rear floor part 19a, the distance between the receiver 28 on the watercraft body 10 and the communication terminal 29 increases, and the communication level between them decreases. The determination unit 73 determines that the luggage P has fallen overboard at the time when such a change in the communication state is confirmed. In this case, the luggage P corresponds to the “mounted object” in the present disclosure, and the rear floor part 19a corresponds to the “sub-boarding section” in the present disclosure.

In the above embodiment, an example has been described in which the present disclosure is applied to the three-seater personal watercraft 1 on which the two passengers M2 in addition to the driver M1 can be on board. However, the personal watercraft to which the present disclosure can be applied is not limited to such a three-seater personal watercraft. For example, the present disclosure can be similarly applied to a two-seater personal watercraft on which one passenger in addition to the driver can be on board, and a personal watercraft that on which four or more occupants including the driver can be on board.

Here, when the first passenger M2a is on board behind the driver M1 and there is a rear mounted object including a passenger or luggage further behind the first passenger M2a, this rear mounted object is hidden behind the first passenger M2a, and as a result, the driver M1 hardly confirms the state of the rear mounted object. However, according to the personal watercraft of the present disclosure including the notification unit that notifies falling overboard of the mounted objects, the driver can be appropriately notified of the falling overboard of the rear mounted objects hidden by the first passenger. Therefore, the present disclosure is suitable for a personal watercraft including a mounting space for some kind of mounted objects (passengers or luggage) behind the first passenger.

However, in the present disclosure, boarding of a passenger is not essential. That is, also in a case where luggage is mounted behind the driver in a personal watercraft on which only the driver is on board, the present disclosure is applicable in order to notify the driver of falling overboard of the luggage. The luggage behind the driver is not necessarily mounted on the boarding platform (extension deck). That is, the present disclosure is applicable also to a personal watercraft not including a boarding platform.

In the above embodiment, the internal combustion engine 4 is used as the source of the propulsive force applied to the watercraft body 10, that is, the drive source, but the drive source is not limited to the engine. For example, an electric motor may be used as a drive source, or a hybrid drive source in which an electric motor and an engine are combined may be used.

In the above embodiment, an example in which the present disclosure is applied to the personal watercraft 1 that planes by the jet water flow injected from the jet pump 3, that is, a jet propulsion watercraft has been described. However, the personal watercraft to which the present disclosure can be applied is only required to be a personal watercraft that can move on water in a planing state and is not limited to the jet propulsion watercraft. Preferably, the present disclosure can be applied to a saddle-ride type propulsion watercraft in which the posture of the watercraft body tends to greatly change due to the weight movement or the turning operation of the driver.

Summary

The embodiment and its modifications include the following disclosure.

A personal watercraft according to one aspect of the present disclosure includes: a watercraft body including a boarding section on which a driver boards and a sub-boarding section on which a mounted object other than the driver is mounted; a mounted object overboard detection unit that detects that the mounted object has fallen overboard from the watercraft body; and a notification unit that performs notification control to notify the driver of the falling overboard through a specific control target when the mounted object overboard detection unit detects that the mounted object has fallen overboard.

According to the present disclosure, it is possible to notify a driver of falling overboard of a mounted object by notification control. As a result, it is possible to urge the driver to take an action such as causing the personal watercraft to direct to the point of falling overboard, for example, in order to collect the mounted object.

Preferably, the personal watercraft further includes a drive source that generates a driving force for moving the watercraft body. The notification unit controls, as the notification control, the drive source in a special mode different from a mode before detection of falling overboard of the mounted object.

This aspect makes it possible to cause the driver to feel an abnormality through a change in the operation mode of the drive source. Due to this, even in a situation where it is difficult for the driver to recognize only by sound or display, for example, at the time of planing at a high speed, it is possible to notify the driver of the falling overboard of the mounted object.

Specifically, in the special mode, output of the drive source is restricted as compared with output before detection of falling overboard of the mounted object.

This aspect makes it possible to cause the driver to intuitively feel an abnormality through the output restriction of the drive source.

Preferably, the mounted object overboard detection unit includes a communication terminal attached to the mounted object, and a determination unit that determines whether or not the mounted object has fallen overboard based on a communication state with the communication terminal.

This aspect makes it possible to appropriately determine falling overboard of a mounted object based on a communication state with the communication terminal attached to the mounted object. Unlike a case of use of a sensor that responds to the weight of a mounted object, for example, it is hardly affected by a posture change of the mounted object, acceleration/deceleration of the watercraft, a posture change of the watercraft, or the like, and it is possible to reduce the possibility of erroneously determining falling overboard of the mounted object.

Preferably, the determination unit determines, based on a communication state with the communication terminal, each of whether or not a first condition has been satisfied, the first condition being that the mounted object has been mounted on the watercraft body during a planing preparation period, and whether or not a second condition has been satisfied, the second condition being that the mounted object has been separated from the watercraft body exceeding a predetermined distance during planing, and when both of the first condition and the second condition are confirmed to be satisfied, determines that the mounted object has fallen overboard.

This aspect makes it possible to determine falling overboard targeting only a mounted object that has been recognized to be mounted during a planing preparation period (before planing), and possible to reduce the possibility of erroneous determination of falling overboard.

The mounted object may be a passenger, and the sub-boarding section may be a passenger seat on which the passenger can be seated.

This aspect makes it possible to notify the driver of falling overboard of the passenger when the passenger falls overboard from the watercraft body.

The mounted object may be luggage, and the sub-boarding section may be luggage storage provided at a rear of a seat on which the driver is seated.

This aspect makes it possible to notify the driver of falling overboard of the luggage mounted on the watercraft body.

Preferably, the personal watercraft further includes: a driver overboard detection unit that detects that the driver has fallen overboard from the watercraft body; a power unit that moves the watercraft body; and a control unit that controls the power unit in a mode different from a mode at a time of detection of falling overboard of the mounted object in a case where the driver overboard detection unit detects falling overboard of the driver.

This aspect makes it possible to control the power unit so that the driver who has fallen overboard can easily return to the personal watercraft.

Specifically, when falling overboard of the driver is detected, the control unit controls the power unit so that movement of the watercraft body is restricted as compared with movement of the watercraft body before the detection of the falling overboard.

In this aspect, since the personal watercraft can be kept in a vicinity of the point of falling overboard of the driver, it is possible to facilitate an action of returning to the personal watercraft of the driver who has fallen overboard.

More specifically, the power unit includes a drive source, a jet pump that is rotationally driven by the drive source and injects water, and a reverse bucket that is swingably arranged at an outlet of the jet pump. When falling overboard of the driver is detected, the control unit restricts movement of the watercraft body by stopping the drive source or changing a position of the reverse bucket to a neutral position. When falling overboard of the mounted object is detected, the notification unit restricts output of the drive source while continuing operation of the drive source as compared with output before detection of falling overboard of the mounted object.

In this aspect, since the drive source is stopped or the position of the reverse bucket is set to the neutral position at the time of falling overboard of the driver, it is possible to keep the personal watercraft in the vicinity of the point of falling overboard of the driver. On the other hand, when not the driver but the mounted object falls overboard, the output of the drive source is only restricted, and the operation itself of the drive source is continued. Therefore, the driver can cause the personal watercraft to direct to the point of falling overboard of the mounted object without any trouble, and can promptly collect the mounted object that has fallen overboard.

When falling overboard of the driver is detected, the control unit may control the power unit so that the watercraft body remains in an area where a distance from a point of falling overboard of the driver to the watercraft body is equal to or less than a predetermined value.

This aspect makes it possible to control the position of the personal watercraft so as to remain in the vicinity of the point of falling overboard of the driver.

A personal watercraft according to another aspect of the present disclosure includes: a watercraft body including a boarding section on which a driver boards and a sub-boarding section on which a mounted object other than the driver is mounted; a determination unit that determines whether or not the mounted object has fallen overboard from the watercraft body based on presence or absence of the mounted object detected during a planing preparation period and presence or absence of the mounted object detected during subsequent planing; and a notification unit that performs notification control to notify the driver of the falling overboard through a specific control target when the determination unit determines that the mounted object has fallen overboard.

This aspect makes it possible to appropriately determine whether or not the mounted object has fallen overboard based on the presence or absence of the mounted object during the planing preparation period and during the planing. When it is determined that the mounted object has fallen overboard, it is possible to notify the driver of the falling overboard by the notification control.

Claims

1. A personal watercraft comprising:

a watercraft body including a boarding section on which a driver boards and a sub-boarding section on which a mounted object other than the driver is mounted;

a mounted object overboard detection unit that detects that the mounted object has fallen overboard from the watercraft body; and

a notification unit that performs notification control to notify the driver of the falling overboard through a specific control target when the mounted object overboard detection unit detects that the mounted object has fallen overboard.

2. The personal watercraft according to claim 1, further comprising a drive source that generates a driving force for moving the watercraft body,

wherein the notification unit controls, as the notification control, the drive source in a special mode different from a mode before detection of falling overboard of the mounted object.

3. The personal watercraft according to claim 2, wherein in the special mode, output of the drive source is restricted as compared with output before detection of falling overboard of the mounted object.

4. The personal watercraft according to claim 1, wherein the mounted object overboard detection unit includes a communication terminal attached to the mounted object, and a determination unit that determines whether or not the mounted object has fallen overboard based on a communication state with the communication terminal.

5. The personal watercraft according to claim 4, wherein the determination unit determines, based on a communication state with the communication terminal, each of whether or not a first condition has been satisfied, the first condition being that the mounted object has been mounted on the watercraft body during a planing preparation period, and whether or not a second condition has been satisfied, the second condition being that the mounted object has been separated from the watercraft body exceeding a predetermined distance during planing, and when both of the first condition and the second condition are confirmed to be satisfied, determines that the mounted object has fallen overboard.

6. The personal watercraft according to claim 1, wherein

the mounted object is a passenger, and

the sub-boarding section is a passenger seat on which the passenger can be seated.

7. The personal watercraft according to claim 1, wherein

the mounted object is luggage, and

the sub-boarding section is luggage storage provided at a rear of a seat on which the driver is seated.

8. The personal watercraft according to claim 1, further comprising:

a driver overboard detection unit that detects that the driver has fallen overboard from the watercraft body;

a power unit that moves the watercraft body; and

a control unit that controls the power unit in a mode different from a mode at a time of detection of falling overboard of the mounted object in a case where the driver overboard detection unit detects falling overboard of the driver.

9. The personal watercraft according to claim 8, wherein when falling overboard of the driver is detected, the control unit controls the power unit so that movement of the watercraft body is restricted as compared with movement of the watercraft body before the detection of the falling overboard.

10. The personal watercraft according to claim 9, wherein

the power unit includes a drive source, a jet pump that is rotationally driven by the drive source and injects water, and a reverse bucket that is swingably arranged at an outlet of the jet pump,

when falling overboard of the driver is detected, the control unit restricts movement of the watercraft body by stopping the drive source or changing a position of the reverse bucket to a neutral position, and

when falling overboard of the mounted object is detected, the notification unit restricts output of the drive source while continuing operation of the drive source as compared with output before detection of falling overboard of the mounted object.

11. The personal watercraft according to claim 9, wherein when falling overboard of the driver is detected, the control unit controls the power unit so that the watercraft body remains in an area where a distance from a point of falling overboard of the driver to the watercraft body is equal to or less than a predetermined value.

12. A personal watercraft comprising:

a watercraft body including a boarding section on which a driver boards and a sub-boarding section on which a mounted object other than the driver is mounted;

a determination unit that determines whether or not the mounted object has fallen overboard from the watercraft body based on presence or absence of the mounted object detected during a planing preparation period and presence or absence of the mounted object detected during subsequent planing; and

a notification unit that performs notification control to notify the driver of the falling overboard through a specific control target when the determination unit determines that the mounted object has fallen overboard.