PROPULSION DEVICE CONTROL APPARATUS

Description

BACKGROUND OF THE INVENTION

Field of the Invention

This invention relates to a propulsion device control apparatus configured to control a propulsion device of a boat.

Description of the Related Art

Conventionally, there has been known a device that controls three propulsion devices mounted on a boat according to the operation of two right and left levers. Such a device is described, for example, in JP 2008-128138 A and JP 2006-035884 A. In the device described in JP 2006-035884 A, a right propulsion device is controlled according to a lever position of a right lever, a left propulsion device is controlled according to a lever position of a left lever, and a virtual lever position between the lever position of the right lever and an operation position of the left lever is calculated, and a middle propulsion device is controlled according to the calculated virtual lever position. In the device described in JP 2008-128138 A, when a main switch of only the right propulsion device is turned off, the middle propulsion device is controlled according to the operation by the right lever, and when a main switch of only the left propulsion device is turned off, the middle propulsion device is controlled according to the operation by the left lever.

However, as in the device described in JP 2008-128138 A, when the middle propulsion device is controlled according to the virtual lever position between the lever position of the right lever and the operation position of the left lever, it is difficult to efficiently use the middle propulsion device when one lever fails. Further, as in the device described in JP 2006-035884 A, when a lever for operating the middle propulsion device is automatically changed according to a situation, there is a possibility that the lever is operated against the intention of a boat operator.

SUMMARY OF THE INVENTION

An aspect of the present invention is a propulsion device control apparatus configured to control a propulsion device of a boat. The apparatus includes: a lever configured to instruct a propulsion direction of forward, neutral, or rearward and a target propulsion force of the propulsion device; and a controller including a processor and a memory coupled to the processor and configured to control the propulsion device based on an instruction from the lever. The propulsion device includes: a right propulsion device provided on a starboard side of the boat; a left propulsion device provided on a port side of the boat; and at least one middle propulsion device provided between the right propulsion device and the left propulsion device. The lever includes: a right lever corresponding to one of the right propulsion device and the left propulsion device; and a left lever corresponding to other of the right propulsion device and the left propulsion device. The controller is configured to switch between: a normal mode in which the middle propulsion device is controlled based on the instruction from the right lever and the instruction from the left lever; and a preset mode in which the middle propulsion device is controlled based on the instruction from a preset lever of the right lever and the left lever. The controller controls the middle propulsion device in the normal mode when both the right lever and the left lever are normal, while limits a propulsion force of the propulsion device corresponding to the one and switches from the normal mode to the preset mode when the one fails.

BRIEF DESCRIPTION OF THE DRAWINGS

The objects, features, and advantages of the present invention will become clearer from the following description of embodiments in relation to the attached drawings, in which:

FIG. 1 is a block diagram schematically illustrating an example of overall configuration of a propulsion device control apparatus according to an embodiment of the present invention;

FIG. 2 is a diagram illustrating an example of a correspondence relationship between a lever position of each lever in FIG. 1 and a propulsion direction of each propulsion device instructed according to the lever position;

FIG. 3 is a diagram illustrating an example of a correspondence relationship between the lever position of each lever in FIG. 1 and target propulsion force of each propulsion device instructed according to the lever position;

FIG. 4 is a flowchart illustrating an example of propulsion force determination processing of a middle propulsion device executed by a middle ECU in FIG. 1;

FIG. 5 is a diagram illustrating propulsion force of the middle propulsion device when the same propulsion direction is instructed by a right lever and a left lever;

FIG. 6 is a diagram illustrating the propulsion force of the middle propulsion device when different propulsion directions are instructed by the right lever and the left lever;

FIG. 7 is a flowchart illustrating another example of the propulsion force determination processing in FIG. 4;

FIG. 8 is a diagram illustrating the propulsion force of the middle propulsion device determined in the propulsion force determination processing in FIG. 7;

FIG. 9 is a flowchart illustrating still another example of the propulsion force determination processing in FIG. 4;

FIG. 10 is a flowchart illustrating still another additional example of the propulsion force determination processing in FIG. 4;

FIG. 11 is a diagram illustrating the propulsion force of the middle propulsion device determined in the propulsion force determination processing in FIG. 9;

FIG. 12 is a flowchart illustrating an example of propulsion force determination mode switching processing of the middle propulsion device executed by the middle ECU;

FIG. 13 is a time chart illustrating a change in the propulsion force of each propulsion device when normal mode is switched to preset mode;

FIG. 14 is a time chart similar to FIG. 13 when the normal mode is switched to the preset mode by the processing in FIG. 12;

FIG. 15 is a flowchart illustrating another example of the propulsion force determination mode switching processing in FIG. 12;

FIG. 16 is a flowchart illustrating still another example of the propulsion force determination mode switching processing in FIG. 12; and

FIG. 17 is a time chart similar to FIGS. 13 and 14 when the normal mode is switched to the preset mode by the processing in FIG. 16.

DETAILED DESCRIPTION OF THE INVENTION

Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1 to 17. FIG. 1 is a block diagram schematically illustrating an example of an overall configuration of a propulsion device control apparatus (hereinafter, the apparatus) 100 according to the embodiment of the present invention. The apparatus 100 is applied to a boat 1 on which three or more propulsion devices 2 are mounted, and controls each of the propulsion devices 2. Each propulsion device 2 may be an engine-driven propulsion device or a motor-driven propulsion device.

As illustrated in FIG. 1, the apparatus 100 mainly includes a plurality of the (for example, three) propulsion devices 2 mounted on the boat 1, and two levers 3 that are provided in a steering seat of the boat 1 and instruct a propulsion direction of any one of “forward”, “neutral”, and “rearward” of each propulsion device 2 and target propulsion force. The plurality of propulsion devices 2 include a right propulsion device 2R provided on the starboard side of the boat 1, a left propulsion device 2L provided on the port side of the boat 1, and one or more (for example, one) middle propulsion devices 2M provided between the right propulsion device 2R and the left propulsion device 2L. The two levers 3 include a right lever 3R corresponding to one (usually the right propulsion device 2R) of the right propulsion device 2R and the left propulsion device 2L, and a left lever 3L corresponding to the other one (usually the left propulsion device 2L) of the right propulsion device 2R and the left propulsion device 2L.

The right propulsion device 2R is connected to a right ECU 20R, and the right propulsion device 2R is controlled by the right ECU 20R. The middle propulsion device 2M is connected to a middle ECU 20M, and the middle propulsion device 2M is controlled by the middle ECU 20M. The left propulsion device 2L is connected to a left ECU 20L, and the left propulsion device 2L is controlled by the left ECU 20L. Hereinafter, the right ECU 20R, the middle ECU 20M, and the left ECU 20L may be collectively referred to as a propulsion device ECU 20.

The right lever 3R and the left lever 3L are connected to a lever ECU 30. The lever ECU 30 is connected to each of the right ECU 20R, the middle ECU 20M, and the left ECU 20L. Instructions from the right lever 3R and the left lever 3L are transmitted to the right ECU 20R, the middle ECU 20M, and the left ECU 20L via the lever ECU 30. Hereinafter, the right ECU 20R, the middle ECU 20M, the left ECU 20L, and the lever ECU 30 may be collectively referred to as a controller 10.

FIG. 2 is a diagram illustrating an example of a correspondence relationship between a lever position of each lever 3 and a propulsion direction of each propulsion device 2 instructed according to the lever position. As illustrated in FIG. 2, each lever 3 is provided to be swingable, for example, in the forward-and-rearward direction of the boat 1. When the lever position of each lever 3 is in the neutral position, “neutral” is instructed as the propulsion direction of each propulsion device 2, in which the boat 1 is not propelled forward or rearward in the neutral position. When the lever position of each lever 3 is in the forward position on the front side of the neutral position, “forward” for propelling the boat 1 forward is instructed as the propulsion direction of each propulsion device 2. When the lever position of each lever 3 is in the rearward position behind the neutral position, “rearward” for propelling the boat 1 rearward is instructed as the propulsion direction of each propulsion device 2.

The center lever position of the neutral position is set to 0%, and the foremost and rearmost lever positions are set to 100%. The lever position of each lever 3 is detected as a voltage value by a potentiometer (not illustrated) and is input to the lever ECU 30.

The lever ECU 30 includes a computer including a processor such as a CPU, a memory such as a ROM and a RAM, and other peripheral circuits. The lever ECU 30 converts a voltage value [V] indicating the lever position input from each lever 3 into a propulsion direction (forward, neutral, rearward) and a lever position [%], and transmits the propulsion direction and the lever position to each propulsion device ECU 20.

FIG. 3 is a diagram illustrating an example of a correspondence relationship between the lever position of each lever 3 and target propulsion force of each propulsion device 2 instructed according to the lever position. When each propulsion device 2 is an engine-driven propulsion device, the propulsion force of each propulsion device 2 is adjusted by, for example, an opening degree or a position (hereinafter, a throttle position TH) of a throttle valve that adjusts an intake amount of an engine. When each propulsion device 2 is a motor-driven propulsion device, the propulsion force of each propulsion device 2 is adjusted by a motor rotation speed. Hereinafter, as an example, a case in which each propulsion device 2 is the engine-driven propulsion device will be described. Therefore, FIG. 3 illustrates the throttle position TH (target value) as the target propulsion force of each propulsion device 2.

As illustrated in FIG. 3, when the lever position in FIG. 2 is in front of 0%, the throttle position TH corresponding to the lever position is set as the target value based on a characteristic at the time of forward movement. When the lever position is behind 0%, the throttle position TH corresponding to the lever position is set as the target value based on a characteristic at the time of rearward movement, which is gentler than the characteristic at the time of forward movement.

Each propulsion device ECU 20 includes a computer having a processor such as a CPU, a memory such as a ROM and a RAM, and other peripheral circuits. Each propulsion device ECU 20 converts the lever position [%] of each lever 3 transmitted from the lever ECU 30 into the throttle position TH (0% to 100%) based on the characteristic of FIG. 3 stored in advance.

Each propulsion device ECU 20 switches the propulsion direction of each propulsion device 2 among “forward”, “neutral”, and “rearward” by controlling a shift mechanism (actuator) connecting an engine to a propeller. When the propulsion direction of each of the propulsion devices 2 is “neutral”, the engine and the propeller are disconnected via the shift mechanism, the propeller does not rotate, and each propulsion device 2 does not propel the boat 1. When the propulsion direction of each of the propulsion devices 2 is “forward” or “rearward”, the engine and the propeller are connected to each other via the shift mechanism, and the propeller rotates according to the engine speed, whereby each of the propulsion devices 2 propels the boat 1 forward or rearward.

In addition, each propulsion device ECU 20 controls the throttle valve (actuator) to adjust the throttle position TH, thereby adjusting the engine speed of each propulsion device 2 and the rotation speed of the propeller. As a result, propulsion force by which each propulsion device 2 propels the boat 1 is adjusted.

The right ECU 20R controls the right propulsion device 2R according to the propulsion direction and the throttle position TH corresponding to the lever position of the right lever 3R transmitted from the lever ECU 30. The left ECU 20L controls the left propulsion device 2L according to the propulsion direction and the throttle position TH corresponding to the lever position of the left lever 3L transmitted from the lever ECU 30.

On the other hand, the middle ECU 20M controls the middle propulsion device 2M in a “normal mode” or a “preset mode”. In the normal mode, the middle ECU 20M controls the middle propulsion device 2M based on the propulsion direction and the throttle position TH corresponding to the lever position of the right lever 3R and the propulsion direction and the throttle position TH corresponding to the lever position of the left lever 3L, which are transmitted from the lever ECU 30. In the preset mode, the middle ECU 20M controls the middle propulsion device 2M according to the propulsion direction and the throttle position TH corresponding to a lever position of a preset lever of the right lever 3R and the left lever 3L transmitted from the lever ECU 30.

<Normal Mode>

FIG. 4 is a flowchart illustrating an example of propulsion force determination processing of the middle propulsion device 2M executed by the middle ECU 20M, and illustrates an example of propulsion force determination processing of the middle propulsion device 2M in the normal mode. When both the right lever 3R and the left lever 3L are normal, the middle ECU 20M controls the middle propulsion device 2M in the normal mode. The processing in FIG. 4 is started when the middle ECU 20M starts, and is repeatedly performed at a predetermined cycle.

As illustrated in FIG. 4, first, in S1 (S: processing step), it is determined whether the propulsion direction corresponding to the lever position of the right lever 3R coincides with the propulsion direction corresponding to the lever position of the left lever 3L. When affirmative determination is made in S1, the processing proceeds to S2, and the middle propulsion device 2M is controlled according to the propulsion direction and the throttle position TH corresponding to the lever position of the preset lever of the right lever 3R and the left lever 3L. On the other hand, when negative determination is made in S1, the processing proceeds to S3, and the middle propulsion device 2M is controlled so that the propulsion direction becomes “neutral” and the throttle position TH becomes 0%. The preset lever is one lever 3 which is selected in advance by a user of the boat 1 (that is, a boat operator) from the right lever 3R and the left lever 3L and is preset. Information indicating whether the preset lever is the right lever 3R or the left lever 3L is stored in advance in the middle ECU 20M.

FIG. 5 is a diagram illustrating propulsion force of the middle propulsion device 2M when the same propulsion direction is instructed by the right lever 3R and the left lever 3L. In the example in FIG. 5, since “forward” is instructed by the right lever 3R and the left lever 3L, the propulsion direction of the middle propulsion device 2M is also controlled to become “forward”. Although not illustrated in the drawing, when “rearward” is instructed by the right lever 3R and the left lever 3L, the propulsion direction of the middle propulsion device 2M is also controlled to become “rearward”. When “neutral” is instructed by the right lever 3R and the left lever 3L, the propulsion direction of the middle propulsion device 2M is also controlled to become “neutral”.

In the case of “forward” or “rearward”, the propulsion force of the middle propulsion device 2M is controlled according to the throttle position TH corresponding to the lever position of the preset lever (right lever 3R in FIG. 5). In the case of “neutral”, the throttle position TH is controlled to become 0%.

Such control of the propulsion direction and the propulsion force of the middle propulsion device 2M is automatically performed corresponding to the lever position of the preset lever, but since the preset lever is the lever 3 that is selected by the boat operator himself or herself and is preset, it does not violate the intention of the boat operator. FIG. 6 is a diagram illustrating the propulsion force of the middle propulsion device 2M when different propulsion directions are instructed by the right lever 3R and the left lever 3L. In the example of FIG. 6, since “forward” is instructed by the right lever 3R and “rearward” is instructed by the left lever 3L, the middle propulsion device 2M is controlled so that the propulsion direction becomes “neutral” and the throttle position TH becomes 0%. Although not illustrated herein, when the right lever 3R instructs “forward” and the left lever 3L instructs “neutral”, when the right lever 3R instructs “neutral” and the left lever 3L instructs “forward”, when the right lever 3R instructs “neutral” and the left lever 3L instructs “rearward”, when the right lever 3R instructs “rearward” and the left lever 3L instructs “forward”, and when the right lever 3R instructs “rearward” and the left lever 3L instructs “neutral”, respectively, similarly, the middle propulsion device 2M is controlled so that the propulsion direction becomes “neutral” and the throttle position TH becomes 0%.

For example, for the purpose of turning the boat 1 on the spot, the right lever 3R and the left lever 3L may be tilted to the same extent in opposite directions. When the right lever 3R and the left lever 3L instruct different propulsion directions, the middle propulsion device 2M is set to “neutral” and, as such, the boat operator's intention to turn the boat 1 on the spot is not violated.

FIG. 7 is a flowchart illustrating another example of the propulsion force determination processing in FIG. 4. In the processing of FIG. 7, when affirmative determination is made in S1, the processing proceeds to S4, and the propulsion force of the middle propulsion device 2M is controlled according to an average value of the throttle position TH corresponding to the lever position of the right lever 3R and the throttle position TH corresponding to the lever position of the left lever 3L.

FIG. 8 is a diagram illustrating the propulsion force of the middle propulsion device 2M determined in the propulsion force determination processing in FIG. 7. In the example in FIG. 8, since “forward” is instructed by the right lever 3R and the left lever 3L, the propulsion direction of the middle propulsion device 2M is also controlled to become “forward”. The propulsion force of the middle propulsion device 2M is controlled according to the average value of the throttle position TH corresponding to the lever position of the right lever 3R and the throttle position TH corresponding to the lever position of the left lever 3L. Although not illustrated herein, when “rearward” is instructed by the right lever 3R and the left lever 3L, the propulsion direction of the middle propulsion device 2M is also controlled to become “rearward”, and the propulsion force of the middle propulsion device 2M is controlled according to the average value of the throttle position TH corresponding to the lever position of the right lever 3R and the throttle position TH corresponding to the lever position of the left lever 3L.

FIG. 9 is a flowchart illustrating still another example of the propulsion force determination processing in FIG. 4. In the processing in FIG. 9, when affirmative determination is made in S1, the processing proceeds to S5, and the propulsion force of the middle propulsion device 2M is controlled according to a smaller throttle position TH of the throttle position TH corresponding to the lever position of the right lever 3R and the throttle position TH corresponding to the lever position of the left lever 3L.

FIG. 10 is a flowchart illustrating still another additional example of the propulsion force determination processing in FIG. 4. In the processing in FIG. 10, when affirmative determination is made in S1, the processing proceeds to S6, and the propulsion force of the middle propulsion device 2M is controlled according to a larger throttle position TH of the throttle position TH corresponding to the lever position of the right lever 3R and the throttle position TH corresponding to the lever position of the left lever 3L.

FIG. 11 is a diagram illustrating the propulsion force of the middle propulsion device 2M determined in the propulsion force determination processing in FIG. 9. In the example in FIG. 11, since “forward” is instructed by the right lever 3R and the left lever 3L, the propulsion direction of the middle propulsion device 2M is also controlled to become “forward”. In addition, the propulsion force of the middle propulsion device 2M is controlled according to the smaller throttle position TH of the throttle position TH corresponding to the lever position of the right lever 3R and the throttle position TH corresponding to the lever position of the left lever 3L. Although not illustrated herein, when “rearward” is instructed by the right lever 3R and the left lever 3L, the propulsion direction of the middle propulsion device 2M is also controlled to become “rearward”, and the propulsion force of the middle propulsion device 2M is controlled according to the smaller throttle position TH of the throttle position TH corresponding to the lever position of the right lever 3R and the throttle position TH corresponding to the lever position of the left lever 3L.

<Preset Mode>

Since the normal mode described above is based on the premise that both the right lever 3R and the left lever 3L are normal, the middle propulsion device 2M may not be efficiently used in a state where one of the levers 3 fails.

The failure of the lever 3 includes a failure (a sensor failure) of the potentiometer of the lever 3 that detects the lever position and a communication failure between the lever ECU 30 and the propulsion device ECU 20. When the sensor failure occurs on the lever 3 side, for example, the lever ECU 30 gradually decreases a lever position of the failed lever 3 up to 0% by a predetermined amount (for example, 1%) for each control cycle, and transmits the lever position to the propulsion device ECU 20. When the communication failure occurs between the lever ECU 30 and the propulsion device ECU 20, for example, each propulsion device ECU 20 controls each propulsion device 2 by gradually decreasing the throttle position TH corresponding to the lever position of the failed lever 3 up to 0% by a predetermined amount (for example, 1%) for each control cycle. In other words, the propulsion force of each propulsion device 2 is limited.

When such a failure of the lever 3 occurs, and for example, when the propulsion force of the middle propulsion device 2M is controlled according to the average value of the throttle position TH corresponding to the lever position of the right lever 3R and the throttle position TH corresponding to the lever position of the left lever 3L, the middle propulsion device 2M cannot be efficiently used. That is, since the throttle position TH corresponding to the lever position of the failed lever 3 constantly becomes 0%, the throttle position TH of the middle propulsion device 2M can be used only up to 50%.

Therefore, in the present embodiment, the apparatus 100 is configured as follows so that the middle propulsion device 2M can be efficiently used without violating the intention of the boat operator even when one of the levers 3 fails by switching to the preset mode for controlling the middle propulsion device 2M according to an instruction from the preset lever.

FIG. 12 is a flowchart illustrating an example of propulsion force determination mode switching processing of the middle propulsion device 2M executed by the middle ECU 20M. The processing in FIG. 12 is started when the middle ECU 20M starts, and is repeatedly performed at a predetermined cycle. As illustrated in FIG. 12, first, in S10, it is determined whether both the right lever 3R and the left lever 3L are normal, that is, whether neither the right lever 3R nor the left lever 3L fails. When the affirmative determination is made in S10, the processing proceeds to S11, and the control mode of the middle propulsion device 2M is switched to the normal mode (when the mode is already the normal mode, control in the normal mode is continued).

On the other hand, when negative determination is made in S10, the processing proceeds to S12, and it is determined whether the middle propulsion device 2M is in “neutral”. When affirmative determination is made in S12, the processing proceeds to S13, and it is determined whether the lever position of the preset lever is in the neutral position and the “neutral” propulsion direction is instructed from the preset lever. When the affirmative determination is made in S13, the processing proceeds to S14, and the control mode of the middle propulsion device 2M is switched to the preset mode (when the mode is already the preset mode, control in the preset mode is continued). On the other hand, when negative determination is made in S12 or S13, the processing proceeds to S11, and the control mode of the middle propulsion device 2M is set to the normal mode.

FIGS. 13 and 14 are time charts illustrating a change in the propulsion force (throttle position TH) of each propulsion device 2 when the normal mode is switched to the preset mode. In the drawings, a solid line indicates the current throttle position TH of the middle propulsion device 2M, a two-dot chain line indicates the throttle position TH corresponding to the lever position of the right lever 3R, and a one-dot chain line indicates the throttle position TH corresponding to the lever position of the left lever 3L. In the examples of FIGS. 13 and 14, the right lever 3R is preselected and preset as the preset lever. Until t1 (t: time point), in the normal mode corresponding to FIG. 9, the propulsion force of the middle propulsion device 2M is controlled according to the smaller throttle position TH of the throttle position TH corresponding to the lever position of the right lever 3R and the throttle position TH corresponding to the lever position of the left lever 3L. More specifically, the throttle position TH corresponding to the lever position of the right lever 3R is maintained at 80%, the throttle position TH corresponding to the lever position of the left lever 3L is maintained at 20%, and the throttle position TH of the middle propulsion device 2M is maintained at 20% according to the smaller throttle position TH.

In such a state, when the left lever 3L, which is not the preset lever, fails at t1 (negative determination in S10 in FIG. 12), the throttle position TH corresponding to the lever position of the left lever 3L gradually decreases from 20% to 0%, and the propulsion force of the left propulsion device 2L decreases (is limited). At this time, as illustrated in FIG. 13, when the throttle position TH (target value) of the middle propulsion device 2M is simply changed from 20% of the failed left lever 3L to 80% of the right lever 3R which is the preset lever, the propulsion force of the middle propulsion device 2M rapidly increases, and the boat 1 is rapidly accelerated.

As in S12 to S14 in FIG. 12, only when the current propulsion direction of the middle propulsion device 2M is “neutral” and the propulsion direction of the right lever 3R, which is the preset lever, is “neutral”, switching from the normal mode to the preset mode is permitted, whereby such sudden acceleration (or sudden deceleration) can be prevented.

That is, as illustrated in FIG. 14, at t1, neither the propulsion direction of the middle propulsion device 2M nor the propulsion direction of the right lever 3R, which is the preset lever, is “neutral”, and thus switching to the preset mode is not permitted (No in S12 and S13 in FIG. 12), and the normal mode is continued (S11). In this case, the throttle position TH corresponding to the lever position of the failed left lever 3L decreases from 20% to 0%, the throttle position TH of the middle propulsion device 2M also decreases from 20% to 0%, and the propulsion force of the left propulsion device 2L and the middle propulsion device 2M decreases (is limited). Thereafter, when the boat operator operates the right lever 3R to set the lever position to 0% at t2 (YES in S12 and S13 in FIG. 12), switching from the normal mode to the preset mode is permitted at t3 (S14). Thereafter, the propulsion direction and the propulsion force of the right propulsion device 2R and the middle propulsion device 2M are controlled according to the operation of the right lever 3R by the boat operator. In this case, although the middle propulsion device 2M cannot be used until the boat operator operates the right lever 3R, which is the preset lever, to set the lever position to 0%, the operation of the middle propulsion device 2M according to the intention of the boat operator can be implemented.

It is noted that, in the preset mode in a case where the preset lever fails, since the throttle position TH corresponding to the lever position of the failed preset lever decreases up to 0%, the throttle position TH of the middle propulsion device 2M according to the instruction from the preset lever also decreases up to 0%, and the propulsion force of the middle propulsion device 2M decreases (is limited).

Although not illustrated in the drawing, even if the current propulsion direction of the middle propulsion device 2M is “neutral” (YES in S12), when the propulsion direction of the preset lever is not “neutral” (NO in S13), switching to the preset mode is not permitted, so that it is also possible to prevent the propulsion force of the middle propulsion device 2M from being suddenly generated. For example, as illustrated in FIG. 6, when the right lever 3R and the left lever 3L are operated in opposite directions to turn the boat 1 on the spot, it is possible to prevent the propulsion force of the middle propulsion device 2M from being suddenly generated when the lever 3 fails.

FIG. 15 is a flowchart illustrating another example of the propulsion force determination mode switching processing in FIG. 12. In the processing in FIG. 15, when negative determination is made in S10, the processing proceeds to S15, and it is determined whether a difference between the current throttle position TH of the middle propulsion device 2M and the throttle position TH corresponding to the lever position of the preset lever is equal to or less than a predetermined value a. When affirmative determination is made in S15, the processing proceeds to S14, and the control mode of the middle propulsion device 2M is set to the preset mode. On the other hand, when negative determination is made in S15, the processing proceeds to S11, and the control mode of the middle propulsion device 2M is set to the normal mode.

In this case, as illustrated in FIG. 14, when the boat operator operates the right lever 3R, which is the preset lever, at t2 and the lever position after the operation approaches the current throttle position TH of the middle propulsion device 2M, switching from the normal mode to the preset mode is permitted at t3. In this case, although the middle propulsion device 2M cannot be used until the boat operator operates the right lever 3R which is the preset lever, the operation of the middle propulsion device 2M according to the intention of the boat operator can be implemented without rapidly changing the propulsion force of the middle propulsion device 2M.

FIG. 16 is a flowchart illustrating still another example of the propulsion force determination mode switching processing in FIG. 12. In the processing in FIG. 16, when negative determination is made in S10, the processing proceeds to S14, and the control mode of the middle propulsion device 2M is set to the preset mode. Next, in step S16, it is determined whether the difference between the current throttle position TH of the middle propulsion device 2M and the throttle position TH corresponding to the lever position of the preset lever is equal to or less than a predetermined value p. When affirmative determination is made in S16, the processing proceeds to S17, the throttle position TH corresponding to the lever position of the preset lever is set as a target value as it is, and the middle propulsion device 2M is controlled.

On the other hand, when negative determination is made in S16, the processing proceeds to S18, and the middle propulsion device 2M is controlled so that the current throttle position TH gradually changes up to the throttle position TH instructed by the preset lever. For example, the target value is calculated by adding, to the current throttle position TH, a value obtained by multiplying a difference between the current throttle position TH and the throttle position TH of the preset lever by a predetermined coefficient k (k<1), thereby controlling the middle propulsion device 2M. The coefficient k may be a constant or, for example, a variable determined according to the difference between the current throttle position TH and the throttle position TH of the preset lever. For example, the coefficient k is set to a smaller value as the difference between the current throttle position TH and the throttle position TH of the preset lever is larger. In the normal mode, when a change amount of the throttle position TH (target value) per unit time is set as a predetermined value 7 (for example, 10% per 10 msec), such a predetermined value 7 may be multiplied by the coefficient k.

FIG. 17 is a time chart similar to FIGS. 13 and 14 when the normal mode is switched to the preset mode by the processing in FIG. 16. As illustrated in FIG. 17, when the left lever 3L, which is not the preset lever, fails at t1, switching from the normal mode to the preset mode is immediately permitted (from S10 to S14 in FIG. 16). Then, when a difference between the current throttle position TH of the middle propulsion device 2M when switching to the preset mode is permitted and the throttle position TH of the right lever 3R, which is the preset lever, is larger than the predetermined value p, the propulsion force of the middle propulsion device 2M is controlled so as to gradually change up to the throttle position TH of the preset lever (from S16 to S18).

In this case, immediately after the failure of one of the levers 3, the middle propulsion device 2M is controlled according to the preset lever that does not fail, so that the middle propulsion device 2M can be efficiently used without violating the intention of the boat operator. Further, when the current throttle position TH and the throttle position TH of the preset lever deviate from each other, the propulsion force of the middle propulsion device 2M is controlled to gradually change and, as such, the propulsion force of the middle propulsion device 2M is not suddenly changed.

The preset mode described above is also used when the right propulsion device 2R or the left propulsion device 2L is not operating normally. A case in which the propulsion device 2 is not operated normally includes a case in which the propulsion device 2 is not operated because the propulsion device 2 or the propulsion device ECU 20 is turned off, and a case in which the propulsion device 2 and the propulsion device ECU 20 are turned on but the propulsion device 2 or the propulsion device ECU 20 is not operated normally due to a failure.

The middle ECU 20M determines whether both the right propulsion device 2R and the left propulsion device 2L are normally operating. Thereafter, when negative determination is made, the middle ECU 20M determines that the right propulsion device 2R or the left propulsion device 2L is not normally operating, and switches the control mode of the middle propulsion device 2M to the preset mode (when the current mode is already the preset mode, control in the preset mode is continued).

For example, in a case where the right lever 3R is preselected and preset as the preset lever, when it is determined that the right propulsion device 2R is not operating normally, the middle ECU 20M controls the middle propulsion device 2M according to an instruction from the right lever 3R which is the preset lever, and the left ECU 20L controls the left propulsion device 2L according to an instruction from the left lever 3L. When it is determined that the left propulsion device 2L is not normally operated, both the right ECU 20R and the middle ECU 20M control the right propulsion device 2R according to the instruction from the right lever 3R. Even when the right propulsion device 2R or the left propulsion device 2L is not operated normally, the middle propulsion device 2M can be efficiently used without violating the intention of the boat operator by controlling the middle propulsion device 2M in the preset mode.

According to the present embodiment, the following operations and effects can be achieved.

(1) The apparatus 100 controls the propulsion device 2 of the boat 1. The apparatus 100 includes the lever 3 instructing a propulsion direction of any one of “forward”, “neutral”, and “rearward” of the propulsion device 2 and target propulsion force (the throttle position TH (target value)), and the controller 10 (the right ECU 20R, the middle ECU 20M, the left ECU 20L, and the lever ECU 30) that has a processor and a memory connected to the processor and is configured to control the propulsion device 2 based on an instruction from the lever 3 (FIG. 1).

The propulsion device 2 includes the right propulsion device 2R provided on the starboard side of the boat 1, the left propulsion device 2L provided on the port side of the boat 1, and at least one middle propulsion device 2M provided between the right propulsion device 2R and the left propulsion device 2L (FIG. 1). The lever 3 includes the right lever 3R corresponding to one of the right propulsion device 2R and the left propulsion device 2L, and the left lever 3L corresponding to the other one of the right propulsion device 2R and the left propulsion device 2L (FIG. 1).

The controller 10 switches between a normal mode in which the middle propulsion device 2M is controlled based on an instruction from the right lever 3R and an instruction from the left lever 3L and a preset mode in which the middle propulsion device 2M is controlled based on an instruction from a preset lever of the right lever 3R and the left lever 3L (FIG. 12, FIG. 15, and FIG. 16).

The controller 10 controls the middle propulsion device 2M in the normal mode when both the right lever 3R and the left lever 3L are normal. Further, when one of the right lever 3R and the left lever 3L fails, the controller 10 limits propulsion force of the propulsion device 2 corresponding to the failed lever of the right propulsion device 2R and the left propulsion device 2L, and switches from the normal mode to the preset mode (FIG. 12, FIG. 15, and FIG. 16). As a result, even when one of the right lever 3R and the left lever 3L fails, the middle propulsion device 2M can be efficiently used without violating the intention of the boat operator.

(2) When one of the right lever 3R and the left lever 3L fails, the controller 10 switches from the normal mode to the preset mode on condition that the propulsion direction of the middle propulsion device 2M is “neutral” and the propulsion direction instructed by the preset lever is “neutral” (FIG. 12 and FIG. 14). As a result, when the lever 3 fails, it is possible to prevent the boat 1 from rapidly accelerating or rapidly decelerating, and to prevent the propulsion force of the middle propulsion device 2M from being suddenly generated, thereby making it possible to improve operability and ride comfort for the boat operator.

(3) In the normal mode, when the propulsion direction instructed from the right lever 3R is different from the propulsion direction instructed from the left lever 3L, the controller 10 controls the middle propulsion device 2M to change the propulsion direction to “neutral” (S1 to S3 in FIG. 4 and FIG. 6). In this case, as illustrated in FIG. 6, the boat 1 can be turned on the spot by operating the right lever 3R and the left lever 3L in opposite directions. When the lever 3 fails in such a state, switching from the normal mode to the preset mode is permitted on condition that the propulsion direction of the preset lever is “neutral” (S13 in FIG. 12). Therefore, when the lever 3 fails, it is possible to prevent the propulsion force of the middle propulsion device 2M from being suddenly generated, thereby making it possible to improve operability and ride comfort for the boat operator.

(4) When one of the right lever 3R and the left lever 3L fails, the controller 10 switches from the normal mode to the preset mode on condition that a difference between the throttle position TH of the middle propulsion device 2M and the throttle position TH instructed by the preset lever is equal to or less than the predetermined value a (FIG. 15). In this case, as illustrated in FIG. 14, the operation of the middle propulsion device 2M according to the intention of the boat operator can be implemented without rapidly changing the propulsion force of the middle propulsion device 2M.

(5) In a case where the difference between the current throttle position TH of the middle propulsion device 2M and the throttle position TH instructed by the preset lever is equal to or larger than the predetermined value p when the mode is switched from the normal mode to the preset mode, the controller 10 controls the middle propulsion device 2M so that the current throttle position TH gradually changes up to the throttle position TH instructed by the preset lever (from S20 to S22 in FIG. 16). In this case, as illustrated in FIG. 17, immediately after one lever 3 fails, the middle propulsion device 2M is controlled according to the preset lever that does not fail. Therefore, the middle propulsion device 2M can be efficiently used without violating the intention of the boat operator. Further, when the current throttle position TH and the throttle position TH of the preset lever deviate from each other, the propulsion force of the middle propulsion device 2M is controlled to gradually change and, as such, the propulsion force of the middle propulsion device 2M is not suddenly changed.

(6) When at least one of the right propulsion device 2R and the left propulsion device 2L fails, the controller 10 controls the middle propulsion device 2M in the preset mode. Even when the right propulsion device 2R or the left propulsion device 2L is not operated normally, the middle propulsion device 2M can be efficiently used without violating the intention of the boat operator by controlling the middle propulsion device 2M in the preset mode. That is, when the right propulsion device 2R and the left propulsion device 2L are operated normally or when any one of the right propulsion device 2R and the left propulsion device 2L is not operated normally, the preset lever of the middle propulsion device 2M is not changed, and the boat operator can easily perform an operation.

(7) In the preset mode, the controller 10 limits the propulsion force of the middle propulsion device 2M when the preset lever fails. That is, in the preset mode when the preset lever fails, the throttle position TH of the middle propulsion device 2M according to the instruction from the failed preset lever is limited to 0%, and the propulsion force of the middle propulsion device 2M is limited. That is, even when the preset lever fails, the preset lever of the middle propulsion device 2M is not changed. Therefore, the middle propulsion device 2M is not controlled according to the instruction from the lever 3 not intended by the boat operator (not preset), and it is possible to prevent the operation of the middle propulsion device 2M contrary to the intention of the boat operator.

In the above embodiment, the boat 1 illustrated in FIG. 1 and the like may be any boat such as a runabout boat or a pontoon boat. The hull shape of the boat 1 may be any shape such as a flat type, a V-type, a round type, and a multi-hull type.

In the above embodiment, the propulsion device 2 illustrated in FIG. 1 and the like may be configured as an outboard engine, or may be configured as an inboard engine or an inboard-outdrive engine.

In the above embodiment, one middle propulsion device 2M has been described as an example in FIG. 1 and the like, but two or more middle propulsion devices provided between the right propulsion device provided on the starboard side of the boat and the left propulsion device provided on the port side thereof may be provided. In a case where four propulsion devices 2 are mounted on the boat 1, two propulsion devices 2 provided between the right propulsion device 2R on the most starboard side and the left propulsion device 2L on the most port side can be controlled as the middle propulsion device 2M. In a case where five propulsion devices 2 are mounted on the boat 1, three propulsion devices 2 provided between the right propulsion device 2R on the most starboard side and the left propulsion device 2L on the most port side may be controlled as the middle propulsion device 2M, and one propulsion device 2 provided between two right propulsion devices 2R on the starboard side and two left propulsion devices 2L on the port side may be controlled as the middle propulsion device 2M.

In the above embodiment, the specific shape and operation of the lever 3 have been described with reference to FIG. 2 and the like, but the right lever and the left lever are not limited to such shape and operation. The lever 3 may be any lever as long as the lever 3 instructs the propulsion direction and the target propulsion force of each propulsion device 2 according to the operation by the boat operator. For example, the lever 3 may be displayed on a touch panel display in an operable manner. Alternatively, the lever 3 may be a pedal type operable by foot.

In the above embodiment, the lever ECU 30 and the propulsion device ECU 20 provided corresponding to the plurality of propulsion devices 2 have been described as an example in FIG. 1 and the like, but the controller configured to control the propulsion device based on the instruction from the lever is not limited to such a controller. For example, the lever ECU 30 may not be provided, and a voltage value indicating the lever position may be directly input from each lever 3 to the propulsion device ECU 20. The plurality of propulsion devices 2 may be controlled by a single propulsion device ECU 20. The propulsion direction and the propulsion force of each propulsion device 2 may be determined on the lever ECU 30 side. An additional hub ECU may be provided between the lever ECU 30 and the propulsion device ECU 20, and the hub ECU may determine the propulsion direction and the propulsion force of each propulsion device 2 based on information from the lever ECU 30.

In the above embodiment, an example has been described in which the propulsion force by which each propulsion device 2 propels the boat 1 is adjusted by adjusting the engine speed of each propulsion device 2 and the rotational speed of the propeller via the throttle position TH. However, a propulsion device of a boat is not limited to such a configuration. For example, the propulsion force of the propulsion device may be adjusted by adjusting the engine speed via a fuel injection amount. Alternatively, the propulsion force of the propulsion device may be adjusted by adjusting the motor rotation speed.

The above embodiment can be combined as desired with one or more of the aforesaid modifications. The modifications can also be combined with one another.

According to the present invention, it becomes possible to even when one of the levers fails, the middle propulsion device can be efficiently used without violating the intention of the boat operator.

Above, while the present invention has been described with reference to the preferred embodiments thereof, it will be understood, by those skilled in the art, that various changes and modifications may be made thereto without departing from the scope of the appended claims.