US20080254690A1

US20080254690A1 - Emergency engine shutoff apparatus and accident determining apparatus for ship

Info

Publication number: US20080254690A1
Application number: US12/101,499
Authority: US
Inventors: Kazuyoshi Kishibata
Original assignee: Kokusan Denki Co Ltd
Current assignee: Mahle Electric Drive Systems Co Ltd
Priority date: 2007-04-12
Filing date: 2008-04-11
Publication date: 2008-10-16
Also published as: JP2008260413A

Abstract

An emergency engine shutoff apparatus for shutting off an engine in an accident of a ship having a hull and an outboard engine system is provided which includes: an acceleration detector for detecting an acceleration applied in a longitudinal direction of the hull and an acceleration applied in a vertical direction of the hull; an accident determining apparatus for determining that a collision accident occurred when the acceleration applied in a longitudinal direction of the hull exceeds a threshold, and for determining that a capsize accident occurred when a roll angle of the ship exceeds a threshold, the roll angle being arithmetically operated by using the acceleration in the vertical direction; and an engine shutoff apparatus for shutting off the engine by stopping fuel supply to the engine when it is determined that a collision accident or a capsize accident occurred.

Description

TECHNICAL FIELD OF THE INVENTION

The present invention relates to an emergency engine shutoff apparatus which shuts off an engine for the safety of crew in an accident of a ship having a hull and a propulsion apparatus having the engine as a driving source.

PRIOR ART OF THE INVENTION

An emergency engine shutoff apparatus for shutting off a propulsion apparatus engine of a ship when a driver of the ship falls in the water is disclosed in Japanese Utility Model Examined Application Publication No. 5-48344 and Japanese Patent Application Laid-Open No. 2-221637. This type of apparatus comprises: an emergency switch provided for shutting off an engine in operation; a switch operating member which is removably mounted to an operation section of the emergency switch for holding the emergency switch in a non-operated state; and a rope or the like for connecting the switch operating member to a part of a body of a ship navigator, so that when the ship navigator falls in the water, the switch operating member is removed from the emergency switch to cause the emergency switch to be in the non-operated state to shut off the engine.
As described above, conventional emergency engine shutoff apparatuses for ship comprise means for shutting off an engine when a ship navigator falls in the water, but did not comprise means for shutting off an engine when a hull of the ship collides with something or capsizes.
As a result, in a conventional ship, when an accident occurs such as a collision with something or a capsize of the ship, if a ship navigator gets injured so badly that he/she cannot handle the ship and remains in the ship, an engine of the ship could not be shut off. So, the circumstance was dangerous because if crews other than the ship navigator were thrown into the water in the collision or capsize, the crews in the water might get injured or even die by contacting a rotating propeller.
In addition, in a conventional ship, since a propulsion power is continuously supplied after the collision, the hull might run away in an unexpected direction, which might cause a secondary accident.
Furthermore, since a conventional ship was not provided with means for shutting off an engine when a collision accident or a capsize accident occurs, fuel is continuously supplied to the engine after the accident, which might result in fire breakout due to the engine.

SUMMARY OF THE INVENTION

An object of the present invention is to provide an emergency engine shutoff apparatus for ship which can immediately shut off an engine for improving safety when a ship causes a collision accident or a capsize accident.
The present invention relates to an emergency engine shutoff apparatus which shuts off an engine in an accident of a ship having a hull and a propulsion apparatus having the engine as a driving source. In the present invention, an emergency engine shutoff apparatus is provided with an acceleration detector for detecting an acceleration applied onto the hull; an accident determining apparatus having accident determining means for determining a presence/absence of an occurrence of an accident based on an output of the acceleration detector, on the premise that a collision of the hull with something and/or a capsize of the hull is an accident to be determined; and engine shutting off means in accident when the accident determining apparatus determines that an accident occurred.
When a ship causes a collision accident or a capsize accident, an acceleration applied onto the hull changes differently from a normal operation, thereby, as described above, an acceleration detector for detecting an acceleration applied onto the hull enables a determination of a presence/absence of an occurrence of a collision accident or a capsize accident based on the output of the acceleration detector, so that an ignition operation of the engine can be stopped when it is determined that an accident occurred, or the engine can be shut off by stopping a fuel supply to the engine.
In this way, according to the present invention, an engine is shut off in a collision accident or a capsize accident, thereby if crews other than a ship navigator are thrown into the water in a collision or capsize, the probability that the crews in the water might contact a rotating propeller can be eliminated.
Also, according to the present invention, an engine is shut off in a collision accident, thereby even if a ship navigator gets injured so badly that he/she cannot handle a ship, the probability that a hull runs away in an unexpected direction can be eliminated.
In one preferred aspect of the present invention, the above described acceleration detector is provided for detecting at least an acceleration Gx applied in a longitudinal direction of a ship. In this case, an accident determining apparatus is comprised to include an accident determining means for determining that a hull collided with something when an acceleration Gx applied in the longitudinal direction of the ship exceeds a threshold in an acceleration or deceleration of the ship.
In another preferred aspect of the present invention, the above described acceleration detector is provided for detecting at least an acceleration Gy applied in a vertical direction of a ship. In this case, an accident determining apparatus is comprised to include an accident determining means for determining that a ship capsized when a roll angle θr of the ship exceeds a preset threshold, the roll angle θr being obtained based on an arccosine value: cos⁻¹Gy of the acceleration Gy applied in the vertical direction of the ship.
In a further preferred aspect of the present invention, the above described acceleration detector is provided for detecting at least an acceleration Gz applied in a lateral direction of a ship. In this case, an accident determining apparatus is comprised to include an accident determining means for determining that a ship capsized when a roll angle θr of the ship exceeds a preset threshold, the roll angle θr being obtained based on an arcsine value: sin⁻¹Gz of the acceleration Gz applied in the lateral direction of the ship.
In a further preferred aspect of the present invention, the above described acceleration detector is provided for detecting an acceleration Gx applied in a longitudinal direction and an acceleration Gy applied in a vertical direction of a ship. In this case, an accident determining apparatus is comprised to include an accident determining means for determining that a hull collided with something when an acceleration Gx applied in the longitudinal direction of the ship exceeds a threshold, and that the ship capsized when a roll angle θr of the ship exceeds a preset threshold, the roll angle θr being obtained based on an arccosine value: cos⁻¹Gy of the acceleration Gy applied in the vertical direction of the ship.
In a further preferred aspect of the present invention, the above described acceleration detector is provided for detecting an acceleration Gx applied in a longitudinal direction and an acceleration Gz applied in a lateral direction of a ship. In this case, an accident determining apparatus is comprised to include an accident determining means for determining that a hull collided with something when an acceleration Gx applied in the longitudinal direction of the ship exceeds a threshold in an acceleration or deceleration of the ship, and that a ship capsized when a roll angle θr of the ship exceeds a preset threshold, the roll angle θr being obtained based on an arcsine value: sin⁻¹Gz of the acceleration Gz applied in the lateral direction of the ship.
In a further preferred aspect of the present invention, the above described acceleration detector is provided for detecting an acceleration Gz applied in a lateral direction and an acceleration Gy applied in a vertical direction of a ship. In this case, an accident determining apparatus is comprised to include an accident determining means for determining that the ship capsized when a roll angle of the ship exceeds a preset threshold, the roll angle θr being obtained based on an arctangent value: tan⁻¹(Gz/Gy) of a ratio (Gz/Gy) between the acceleration Gz applied in the lateral direction and the acceleration Gy applied in the vertical direction of the ship.
In a further preferred aspect of the present invention, the above described acceleration detector is provided for detecting an acceleration Gx applied in a longitudinal direction, an acceleration Gy applied in a vertical direction of a ship, and an acceleration Gz applied in a lateral direction of a ship. In this case, an accident determining apparatus is comprised to include an accident determining means for determining that a hull collided with something when an acceleration Gx applied in the longitudinal direction of the ship exceeds a threshold in an acceleration or deceleration of the ship, and that the ship capsized when a roll angle θr of the ship exceeds a preset threshold, the roll angle θr being obtained based on an arctangent value tan⁻¹(Gz/Gy) of a ratio (Gz/Gy) between the acceleration Gz applied in the lateral direction and the acceleration Gy applied in the vertical direction of the ship.
When the above described propulsion apparatus is an outboard engine system, and the outboard engine system is provided with a controller for controlling a trim angle of the outboard engine system, controlling an engine, and performing a process to construct the above described accident determining apparatus, the above described acceleration detector is preferably provided in the controller.
In such a structure, when an outboard engine system is mounted to a hull, an acceleration detector does not have to be mounted to the hull, and no wire harness is needed to be extended for connection between an acceleration detector and a controller, thereby the outboard engine system can be simply mounted. In addition, when an outboard engine system has an acceleration detector mounted therein which is adapted to detect at least an acceleration Gy applied in a vertical direction, its inclination relative to the vertical direction of the outboard engine system can be detected based on an output of the acceleration detector, as the result of that, when the information on the inclination relative to the vertical direction of the outboard engine system is used in controlling a trim angle of the outboard engine system, the above described acceleration detector can be used as a detector for acquiring the information.
When an outboard engine system is comprised so that fuel is supplied thereto by a fuel injection apparatus having an injector and a fuel pump for supplying fuel to the injector, the engine shutting off means in accident can be comprised so as to shut off the engine by stopping driving at least one of the fuel pump and the injector to stop the fuel supply to the engine when the accident determining apparatus determines that an accident occurred.
As described above, the engine shutting off means in accident is comprised so as to shut off the engine by stopping a fuel supply to the engine when the accident determining apparatus determines that an accident occurred, the probability that a fire breaks out due to the engine can be eliminated because the fuel supply to the engine is stopped in a collision accident or a capsize accident.
As described above, when an engine is comprised so that fuel is supplied thereto by a fuel injection apparatus having an injector and a fuel pump for supplying fuel to the injector, alternatively, the engine shutting off means in accident can be comprised of: fuel supply stopping means for stopping fuel supply to the engine by stopping driving at least one of the fuel pump and the injector when the accident determining apparatus determines that an accident occurred; and ignition operation stopping means for stopping any ignition operation of the engine when the accident determining apparatus determines that an accident occurred.
In order to prevent a fire breakout in an accident, as described above, it is preferred to stop any fuel supply to the engine in the accident, but the configuration of engine shutting off means in accident is not limited to the one described above, and the engine shutting off means in accident may be comprised only of ignition operation stopping means for stopping any ignition operation of the engine when the accident determining apparatus determines that an accident occurred.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects and features of the invention will be apparent from the detailed description of the preferred embodiments of the invention, which is described and illustrated with reference to the accompanying drawings, in which;

FIG. 1 is a schematic side view showing an example of a ship to which the present invention is applied, with a part of the ship being cross sectioned;

FIG. 2 is a schematic view showing a structure of hardware of an embodiment according to the present invention;

FIG. 3 is a block diagram of a general structure showing main parts of an apparatus having means which is comprised of a microprocessor in an embodiment of the present invention;

FIG. 4 is a side view of main parts showing an acceleration detector which is mounted in an outboard engine system and an acceleration which is detected by the acceleration detector in a first embodiment of the present invention;

FIG. 5 is a graph showing an example of changes in accelerations which are detected by the acceleration detector of FIG. 4;

FIG. 6 is a front view of main parts showing an acceleration detector which is mounted in an outboard engine system and an acceleration which is detected by the acceleration detector in a second embodiment of the present invention;

FIG. 7 is a side view showing the outboard engine system of FIG. 6;

FIG. 8 is a front view showing a state of an outboard engine system when a ship having the outboard engine system of FIG. 6 and FIG. 7 is rolled; and

FIG. 9 is a graph showing the changes in accelerations Gx, Gy and Gz which are obtained by an acceleration detector when a ship is kept in a stopped state and only roll angles of a hull are changed in the embodiment of FIG. 6 to FIG. 8.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Now, with reference to the drawings, preferred embodiments of the present invention will be explained in detail below.
The present invention can be widely applied to ships having a hull and a propulsion apparatus having an engine as a driving source, but in the present embodiment, as shown in FIG. 1, the present invention is applied to a ship 1 which uses an outboard engine system as a propulsion apparatus. In FIG. 1, a reference numeral 2 denotes a hull having a steering wheel 2 a, a throttle lever 2 b, a cockpit 2 c, and the like for steering, and 3 denotes an outboard engine system.
The outboard engine system 3 includes an outboard engine body 303 having an engine 301 and a propeller 302 which is driven by the engine, and brackets 304 which are provided on both sides of a front part of the outboard engine body, and the outboard engine system 3 is mounted to a transom 2 d of the hull 2 via the brackets 304. Between the right and left brackets 304, a power trim system is provided to cause the outboard engine body 303 to be driven by a driving source such as a motor or a hydraulic cylinder to rotate about a rotation shaft 305 which is included in the brackets 304.
FIG. 2 shows an example of a hardware structure of a control section which is comprised of a control apparatus for controlling the engine of the outboard engine system, a control apparatus for the power trim system, and an emergency engine shutoff apparatus according to the present invention. In FIG. 2, a reference numeral 3 denotes an outboard engine system, and 4 denotes a remote control unit which is mounted near the cockpit 2 c in the hull 2.
In FIG. 2, a reference numeral 310 denotes the power trim system provided to the outboard engine system, 311 denotes a controller of the power trim system, and 312 denotes an engine controller. The power trim system 310 includes a power trim motor 315, a trim mechanism for adjusting an inclination of the outboard engine body 303 relative to the hull 2 using a power trim motor as a driving source, and a trim angle sensor 316 for detecting an inclination of the outboard engine body 303 relative to the hull 2.
The controller of the power trim system 311 includes a microprocessor 317 having a CPU, an acceleration detector 318, and a motor drive circuit 319 for supplying a drive current to the power trim motor 315.
Not shown in FIG. 2, but the engine controller 312 also has a microprocessor. The engine controller 312 causes the microprocessor to execute a predetermined program to control an ignition timing of the engine, and to control fuel supplies to the engine.
A remote control unit 4 includes: an auto/manual mode selection switch 401 which is operated by a driver for selecting an operation mode between an automatic control mode and a manual mode; trim command switch 402 which is operated by a driver for operating the outboard engine system to a trim up direction and a trim down direction individually while the manual mode is selected; and a display device 403 for displaying a current trim angle and a current operation mode.
In the present embodiment, the microprocessor included in the power trim controller 312 is used to perform a process to construct an emergency engine shutoff apparatus according to the present invention. FIG. 3 is a block diagram of a general structure of a part related to an emergency engine shutoff apparatus of the present embodiment. In FIG. 3, a reference numeral 2 denotes a hull, 3 denotes an outboard engine system having an outboard engine body 303 and the power trim system 310.
In the present embodiment, a fuel injection apparatus 320 is used to supply fuel to the engine in the outboard engine body. The fuel injection apparatus 320 is a known one that includes an injector provided to inject fuel to a space for fuel injection such as an inside of an intake pipe of an engine, a fuel pump for supplying the fuel to the injector, and an injector control section for controlling the fuel injection duration by the injector so as to cause the injector to inject a predetermined amount of fuel.
The emergency engine shutoff apparatus according to the present invention is comprised of: an acceleration detector 318; an arithmetic operating section 21 for obtaining parameters which are necessary to determine an accident based on an output of the acceleration detector 318; an accident determining means 24 for determining a presence/absence of an accident by using the parameters obtained by the arithmetic operating section 21; and engine shutting off means in accident 25 for shutting off the engine when the accident determining means 24 determines that an accident occurred.
The accident determining means 24 determines whether an accident has occurred or not based on an output of the acceleration detector 318, on the premise that a collision with something and/or a capsize of the hull 2 is an accident to be determined. In the present embodiment, the acceleration detector 318 is comprised of a two-axis acceleration sensor provided for detecting an acceleration Gx applied in a longitudinal direction and an acceleration Gy applied in a vertical direction of the hull 2, and the accident determining means 24 is comprised so as to determine that the hull 2 collided with something when an acceleration Gx applied in the longitudinal direction of the ship exceeds a threshold in an acceleration or deceleration of the ship, and that the ship capsized when a roll angle θr of the ship exceeds a preset threshold, the roll angle θr being obtained based on an arccosine value of the acceleration Gy applied in a vertical direction of the ship.
Herein, among the planes that include the central axis line of the propeller 302 of the outboard engine system 3, the plane which extends along the vertical direction when the hull 2 floats still on the still water is set to be a reference plane, and the direction which extends along the water line of the hull 2 on the reference plane is set to be a longitudinal direction of the ship. The reference plane is parallel to the sheet surface of FIG. 1, and the longitudinal direction of the ship runs along the straight line L of the FIG. 1. Also, a straight line O-O which runs along the outboard engine system 3 at a certain mounting angle θI relative to the longitudinal direction of the ship on the reference plane when the outboard engine system is located at a position for the minimum trim (the trim angle is zero) is set to be a reference axis line of the outboard engine system. The angle of the reference axis line O-O of the outboard engine system relative to the vertical direction on the reference plane is set to be an inclination θo, and the angle obtained by subtracting the mounting angle θI from an angle of the reference axis line of the outboard engine system relative to the longitudinal direction of the ship on the reference plane is set to be a trim angle θt of the outboard engine system. In addition, the inclination of the hull on the plane which includes the reference axis line O-O of the outboard engine system and is orthogonal to the reference plane is set to be a roll angle θr of the ship.
In the present embodiment, since the acceleration sensor 318 is mounted in the controller of the power trim system 311 which is provided in the outboard engine system, for convenience, the direction along the reference axis line O-O is set to be the vertical direction (Y-axis direction) of the ship, and the direction orthogonal to the reference axis line on the reference plane is set to be the longitudinal direction (X-axis direction) of the ship, as shown in FIG. 4. With the longitudinal direction and the vertical direction of the ship being defined as described above, the longitudinal direction and the vertical direction of the ship change depending on a trim angle of the outboard engine system, but it causes no adverse effect in detecting an accident.
The acceleration detector 318 used in the present embodiment detects: as shown in FIG. 4, an acceleration applied in the direction (Y-axis direction) along the reference axis line O-O of the outboard engine system 3 as an acceleration Gy applied in a vertical direction of the ship; and a an acceleration applied in the direction (X-axis direction) orthogonal to the reference axis line O-O on the reference plane as an acceleration Gx applied in a longitudinal direction.
In this case, the arithmetic operating section 21 is comprised of longitudinal direction acceleration reading means 22 for reading an acceleration Gx applied in a longitudinal direction from an output of the acceleration detector 318; and roll angle arithmetic operating means 23 for arithmetically operating a roll angle θr of the ship.
The longitudinal direction acceleration Gx detected by the acceleration detector 318 changes like the curving line a of FIG. 5 when the ship is accelerated, and changes like the curving line b of FIG. 5 when the ship is decelerated in a normal sailing. The horizontal axis of FIG. 5 represents the elapsed time t.
Now, assuming that another ship collides (bumps) the ship in the rear part thereof, the longitudinal direction acceleration Gx changes like the curving line c of FIG. 5 in a wider range than the acceleration (curving line a) when the ship is accelerated in a normal sailing. When the ship collides with something, the longitudinal direction acceleration −Gx changes like the curving line d of FIG. 5 in a wider range than the deceleration (curving line b) when the ship is decelerated in a normal sailing. Therefore, a preset of an appropriate threshold Gd for collision enables a determination of a collision of something with the ship when a longitudinal direction acceleration Gx exceeds the threshold Gd for collision in accelerating of the ship, and also enables a determination of a collision of the ship with something when a longitudinal direction acceleration −Gx exceeds the threshold Gd for collision in decelerating of the ship.
The detection of an acceleration Gy applied in a vertical direction of the ship allows an arithmetic operation of a roll angle θr of the ship using an arithmetic expression θo=cos⁻¹(Gy/Gg)=cos⁻¹Gy, where Gg is gravitational acceleration (=1) and Gy is acceleration in the vertical direction. The roll angle arithmetic operating means 23 shown in FIG. 3 obtains an arccosine value of an acceleration Gy detected by the acceleration detector 318 so as to arithmetically operates a roll angle of the ship, so that the processed value is given to the accident determining means 24.
In this case, the accident determining means 24 determines that the ship collided with something at the front part thereof when the acceleration −Gx applied in the longitudinal direction exceeds the threshold Gd for collision in decelerating the ship, and determines that something hit the ship in the rear part thereof when the acceleration Gx applied in a longitudinal direction exceeds the threshold Gd in accelerating the ship. Also, when a roll angle θr of the ship exceeds the preset threshold θrs, the accident determining means 24 determines that the ship capsized.
When accident determining means 24 determines that a collision accident or a capsize accident occurred, the engine shutting off means in accident 25 shuts off the engine. As in the present embodiment, in a case where fuel is supplied to an engine by using a fuel injection apparatus 320 which has an injector and a fuel pump for supplying fuel to the injector, the engine shutting off means in accident 25 may be comprised so as to, when the accident determining means 24 determines that an accident occurred, shut off the engine by stopping driving at least one of the fuel pump and the injector to stop the fuel supply to the engine.
In a case where an engine is comprised so that fuel is supplied thereto by a fuel injection apparatus 320, the engine shutting off means in accident 25 may also be comprised of fuel supply stopping means for stopping fuel supply to the engine by stopping driving at least one of the fuel pump and the injector when the accident determining means 24 determines that an accident occurred, and ignition operation stopping means for stopping an ignition operation of the engine when the accident determining means 24 determines that an accident occurred.
Alternatively, the engine shutting off means in accident 25 may be comprised only of the ignition operation stopping means for stopping an ignition operation of the engine when the accident determining means 24 determines that an accident occurred.
In the present embodiment, an accident determining apparatus for ship is comprised of the acceleration detector 318, the arithmetic operating section 21, and the accident determining means 24, and the accident determining apparatus and the engine shutting off means in accident 25 comprise an emergency engine shutoff apparatus.
An acceleration Gy in the vertical direction which is detected by an acceleration detector changes in response to a change in a roll angle of a ship as well as a change in a pitch angle. Therefore, a capsize threshold θrs to be compared with the above described roll angle θo (which is sometimes a pitch angle actually) is set to be a value which is sufficiently larger than a critical value of a roll angle and a pitch angle of the ship in a normal sailing (a value that is impossible unless a ship capsizes, such as 90 degrees or more).
In the above explanation, an accident that a ship is collided by something in a rear part thereof and an accident that a ship collides with something at a front part thereof are distinguished from each other for determination, but when a collision is an accident to be determined, the accident determining means may also be comprised so as to determine that an accident occurs when a ship collides with something, so that the accident determining means can determine an occurrence of an accident by comparing the absolute value of an acceleration Gx with a threshold Gd for collision, without distinguishing between a collision accident and a bump accident.
FIG. 6 and FIG. 7 show a second embodiment of the present invention. In the present embodiment, as shown in FIG. 6 and FIG. 7, as an acceleration detector 318, a three-axis acceleration sensor is used which is able to detect accelerations in three axes direction: an acceleration Gx applied in a longitudinal direction; an acceleration Gy applied in a vertical direction (a direction along the reference axis line O-O of an outboard engine system); and an acceleration Gz applied in a lateral direction (a direction orthogonal to the longitudinal direction and the vertical direction).
In the present embodiment, accelerations Gx, Gy, and Gz in the three x, y, and z axis directions respectively which are detected when a ship is stopped and is only under a roll motion change as shown in FIG. 9. That is, since the ship is not moving in the longitudinal direction, the acceleration Gx applied in the longitudinal direction is constantly zero, and the waveform representing the change of the acceleration Gy applied in the vertical direction forms a cosine waveform, and the waveform representing the change of the acceleration Gz applied in the lateral direction forms a sine waveform.
With using such an acceleration detector, a detected value of an acceleration Gx applied in the longitudinal direction is compared with a threshold Gd for collision, so as to be able to determine if a collision accident between the ship and something has occurred or not. Furthermore, by obtaining an arctangent value: tan⁻¹(Gz/Gy) of a ratio (Gz/Gy) between a detected value of an acceleration Gz applied in the lateral direction and a detected value of an acceleration Gy applied in the vertical direction, a roll angle θr of the ship (see FIG. 8) is arithmetically operated, so as to be able to determine if a capsize accident has occurred when the processed roll angle θr exceeds a threshold θrs.
In addition, as described above, when a three-axis acceleration sensor is used as the acceleration detector 318, a roll angle θr can be obtained by using an arccosine value: cos⁻¹Gy of an acceleration Gy applied in the vertical direction or an arcsine value: sin⁻¹Gz of an acceleration Gz applied in the lateral direction.
As described above, when an acceleration Gy applied in the vertical direction and an acceleration Gz applied in the lateral direction can be detected, a roll angle θr of a ship can be obtained by using an arccosine value: cos⁻¹Gy of an acceleration Gy applied in the vertical direction and an arcsine value: sin⁻¹Gz of an acceleration Gz applied in the lateral direction, but in order to accurately determine a presence/absence of a capsize accident of the ship, the change rate of a processed value to the change of a roll angle of a hull is desirably large when a roll angle θr of the hull is close to an angle for a near capsize (around 90 degrees). Thus, in the above described case, a roll angle θr is desirably obtained by using an arccosine value: cos⁻¹Gy of an acceleration Gy applied in the vertical direction.
In the above described embodiment, a two-axis acceleration sensor or a three-axis acceleration sensor is used as the acceleration detector 318, but the acceleration detector 318 may be comprised so as to detect only an acceleration Gx applied in a longitudinal direction when only a collision accident is detected and fuel supply to an engine is stopped.
Also, when only a capsize of a ship is detected and fuel supply to an engine is stopped in a capsize accident, at least one of an acceleration Gy applied in a vertical direction and an acceleration Gz applied in a lateral direction may be detected to arithmetically operate a roll angle θr with θr=cos⁻¹Gy or θr=sin⁻¹Gz, so that the processed value may be compared with a capsize threshold.
In a case where both of a collision accident and a capsize accident are detected, instead of a two-axis acceleration sensor, a combination of two one-axis acceleration sensors may be used, and instead of a three-axis acceleration sensor, a combination of a two-axis acceleration sensor and one one-axis acceleration sensor may be used.
The acceleration detector 318 is preferably mounted in the controller of the power trim system 311 as in the above embodiment, but the present invention is not limited to the structure, and the acceleration detector may be mounted to the hull 2 (for example, in the remote control unit 4).
A roll angle of a ship can be obtained by a trigonometric function, but in arithmetically operating a roll angle, in order to increase the speed of the processing, a map for arithmetically operating a roll angle which provides a relationship between an acceleration and a roll angle is preferably prepared, so that a roll angle can be arithmetically operated by retrieving the map for an acquired acceleration and by performing interpolation.
In each embodiment described above, a ship having an outboard engine system as a propulsion apparatus is used, but the present invention can also be applied to any ship having a propulsion apparatus other than an outboard engine system.
Now, various embodiment of an emergency engine shutoff apparatus for ship according to the present invention will be organized and listed below:
(1) The acceleration detector 318 is provided so as to detect at least an acceleration Gx applied in a longitudinal direction of a ship 1. An accident determining apparatus includes accident determining means for determining that a hull collides with something when an acceleration Gx applied in the longitudinal direction of the ship exceeds a threshold in an acceleration or deceleration of the ship. Engine shutting off means in accident 25 is provided for stopping fuel supply to an engine when the accident determining apparatus determines that an accident occurred.
(2) The acceleration detector 318 is provided so as to detect at least an acceleration Gy applied in a vertical direction of a ship 1. An accident determining apparatus includes accident determining means for determining that the ship capsized when a roll angle θr of the ship exceeds a preset threshold, the roll angle θr being obtained based on an arccosine value: cos⁻¹Gy of the acceleration Gy applied in a vertical direction of the ship. Engine shutting off means in accident 25 is provided for stopping fuel supply to an engine when the accident determining apparatus determines that a capsize accident occurred.
(3) The acceleration detector 318 is provided so as to detect at least an acceleration Gz applied in a lateral direction of a ship 1. An accident determining apparatus includes accident determining means for determining that the ship capsized when a roll angle θr of the ship exceeds a preset threshold, the roll angle θr being obtained based on an arcsine value: sin⁻¹Gz of the acceleration Gz applied in a lateral direction of the ship. Engine shutting off means in accident 25 is provided for stopping fuel supply to an engine when the accident determining apparatus determines that a capsize accident occurred.
(4) The acceleration detector 318 is provided so as to detect an acceleration Gx applied in a longitudinal direction and an acceleration Gy applied in a vertical direction of a ship 1. An accident determining apparatus includes accident determining means for determining that a hull collided with something when an acceleration Gx applied in the longitudinal direction of the ship exceeds a threshold in an acceleration or deceleration of the ship, and for determining that the ship capsized when a roll angle θr of the ship exceeds a preset threshold, the roll angle θr being obtained based on an arccosine value: cos⁻¹Gy of the acceleration Gy applied in a vertical direction of the ship. Engine shutting off means in accident 25 is provided for stopping fuel supply to an engine when the accident determining apparatus determines that an accident occurred.
(5) The acceleration detector 318 is provided so as to detect an acceleration Gx applied in a longitudinal direction and an acceleration Gz applied in a lateral direction of a ship 1. An accident determining apparatus includes accident determining means for determining that a hull collided with something when an acceleration Gx applied in the longitudinal direction of the ship exceeds a threshold in an acceleration or deceleration of the ship, and for determining that the ship capsized when a roll angle θr of the ship exceeds a preset threshold, the roll angle θr being obtained based on an arcsine value: sin⁻¹Gz of the acceleration Gz applied in a lateral direction of the ship. Engine shutting off means in accident 25 is provided for stopping fuel supply to an engine when the accident determining apparatus determines that an accident occurred.
(6) The acceleration detector 318 is provided so as to detect an acceleration Gz applied in a lateral direction and an acceleration Gy applied in a vertical direction of a ship 1. An accident determining apparatus includes accident determining means for determining that the ship capsized when a roll angle of the ship exceeds a preset threshold, the roll angle being obtained based on an arctangent value tan⁻¹(Gz/Gy) of a ratio (Gz/Gy) between an acceleration Gz applied in the lateral direction and an acceleration Gy applied in the vertical direction of the ship. Engine shutting off means in accident 25 is provided for stopping fuel supply to an engine when the accident determining apparatus determines that an accident occurred.
(7) The acceleration detector 318 is provided so as to detect an acceleration Gx applied in a longitudinal direction, an acceleration Gy applied in a vertical direction, and an acceleration Gz applied in a lateral direction of a ship 1. An accident determining apparatus includes accident determining means for determining that a hull collided with something when an acceleration Gx applied in the longitudinal direction of the ship exceeds a threshold in an acceleration or deceleration of the ship, and for determining that the ship capsized when a roll angle θr of the ship exceeds a preset threshold, the roll angle being obtained based on an arctangent value tan⁻¹(Gz/Gy) of a ratio (Gz/Gy) between an acceleration Gz applied in the lateral direction and an acceleration Gy applied in the vertical direction of the ship. Engine shutting off means in accident 25 is provided for stopping fuel supply to an engine when the accident determining apparatus determines that an accident occurred.
(8) In each of the above structures (1) to (7), a propulsion apparatus of the ship is an outboard engine system, and the outboard engine system is provided with a controller therein for controlling a trim angle of the outboard engine system, controlling an engine, and performing a process to construct the accident determining apparatus. In this case, the acceleration detector 318 is provided in the controller.
(9) In a case where an engine is comprised so that fuel is provided thereto by a fuel injection apparatus 320 which has an injector and a fuel pump for supplying fuel to the injector, the engine shutting off means in accident 25 may be comprised so as to shut off the engine by stopping driving at least one of the fuel pump and the injector to stop the fuel supply to the engine when the accident determining apparatus determines that an accident occurred, or may be comprised of fuel supply stopping means for stopping fuel supply to the engine by stopping driving at least one of the fuel pump and the injector when the accident determining apparatus determines that an accident occurred, and ignition operation stopping means for stopping any ignition operation of the engine when the accident determining apparatus determines that an accident occurred.
(10) Alternatively, the engine shutting off means in accident 25 may be comprised of ignition operation stopping means for stopping any ignition operation of the engine when the accident determining apparatus determines that an accident occurred.
Although the preferred embodiments of the invention have been described and illustrated with reference to the accompanying drawings, it will be understood by those skilled in the art that there are by way of examples, and that various changes and modifications may be made without departing from the spirit and scope of the invention, which is defined only to the appended claims.

Claims

1. An emergency engine shutoff apparatus for ship which shuts off an engine in an accident of a ship having a hull and a propulsion apparatus having the engine as a driving source, comprising:

an acceleration detector for detecting an acceleration applied onto the hull;

an accident determining apparatus which includes accident determining means for determining a presence/absence of an accident based on an output of the acceleration detector, on the premise that a collision with something and/or a capsize of the hull is an accident to be determined; and

engine shutting off means in accident for shutting off the engine when the accident determining apparatus determines that an accident occurred.

2. The emergency engine shutoff apparatus for ship according to claim 1, wherein

the acceleration detector is provided so as to detect at least an acceleration Gx applied in a longitudinal direction of the ship, and

the accident determining apparatus includes accident determining means for determining that the hull collided with something when an acceleration Gx applied in the longitudinal direction of the ship exceeds a threshold in an acceleration or deceleration of the ship.

3. The emergency engine shutoff apparatus for ship according to claim 1, wherein

the acceleration detector is provided so as to detect at least an acceleration Gy applied in a vertical direction of the ship, and

the accident determining apparatus includes accident determining means for determining that the ship capsized when a roll angle θr of the ship exceeds a preset threshold, the roll angle θr being obtained based on an arccosine value: cos⁻¹Gy of the acceleration Gy applied in a vertical direction of the ship.

4. The emergency engine shutoff apparatus for ship according to claim 1, wherein

the acceleration detector is provided so as to detect at least an acceleration Gz applied in a lateral direction of the ship, and

the accident determining apparatus includes accident determining means for determining that the ship capsized when a roll angle θr of the ship exceeds a preset threshold, the roll angle θr being obtained based on an arcsine value: sin⁻¹Gz of the acceleration Gz applied in a lateral direction of the ship.

5. The emergency engine shutoff apparatus for ship according to claim 1, wherein

the acceleration detector is provided so as to detect an acceleration Gx applied in a longitudinal direction and an acceleration Gy applied in a vertical direction of the ship, and

the accident determining apparatus includes accident determining means for determining that the hull collided with something when the acceleration Gx applied in the longitudinal direction of the ship exceeds a threshold in an acceleration or deceleration of the ship, and for determining that the ship capsized when a roll angle θr of the ship exceeds a preset threshold, the roll angle θr being obtained based on an arccosine value: cos⁻¹Gy of the acceleration Gy applied in a vertical direction of the ship.

6. The emergency engine shutoff apparatus for ship according to claim 1, wherein

the acceleration detector is provided so as to detect an acceleration Gx applied in a longitudinal direction and an acceleration Gz applied in a lateral direction of the ship, and

the accident determining apparatus includes accident determining means for determining that the hull collided with something when the acceleration Gx applied in the longitudinal direction of the ship exceeds a threshold in an acceleration or deceleration of the ship, and for determining that the ship capsized when a roll angle θr of the ship exceeds a preset threshold, the roll angle θr being obtained based on an arcsine value: sin⁻¹Gz of the acceleration Gz applied in a lateral direction of the ship.

7. The emergency engine shutoff apparatus for ship according to claim 1, wherein

the acceleration detector is provided so as to detect an acceleration Gz applied in a lateral direction and an acceleration Gy applied in a vertical direction of the ship, and

the accident determining apparatus includes accident determining means for determining that the ship capsized when a roll angle of the ship exceeds a preset threshold, the roll angle being obtained based on an arctangent value tan⁻¹(Gz/Gy) of a ratio (Gz/Gy) between the acceleration Gz applied in the lateral direction and the acceleration Gy applied in the vertical direction of the ship.

8. The emergency engine shutoff apparatus for ship according to claim 1, wherein

the acceleration detector is provided so as to detect an acceleration Gx applied in a longitudinal direction, an acceleration Gy applied in a vertical direction, and an acceleration Gz applied in a lateral direction of the ship, and

the accident determining apparatus includes accident determining means for determining that the hull collided with something when the acceleration Gx applied in the longitudinal direction of the ship exceeds a threshold in an acceleration or deceleration of the ship, and for determining that the ship capsized when a roll angle θr of the ship exceeds a preset threshold, the roll angle being obtained based on an arctangent value tan⁻¹(Gz/Gy) of a ratio (Gz/Gy) between the acceleration Gz applied in the lateral direction and the acceleration Gy applied in the vertical direction of the ship.

9. The emergency engine shutoff apparatus for ship according to claim 1, wherein

the propulsion apparatus is an outboard engine system, and the outboard engine system is provided with a controller therein for controlling a trim angle of the outboard engine system, controlling the engine, and performing a process to construct the accident determining apparatus, and

the acceleration detector is provided in the controller.

10. The emergency engine shutoff apparatus for ship according to claim 1, wherein

the engine is comprised so that fuel is supplied thereto by an fuel injection apparatus which has an injector and a fuel pump for supplying fuel to the injector, and

the engine shutting off means in accident is comprised so as to shut off the engine by stopping driving at least one of the fuel pump and the injector to stop fuel supply to the engine when the accident determining apparatus determines that an accident occurred.

11. The emergency engine shutoff apparatus for ship according to claim 1, wherein

the engine shutting off means in accident is comprised of fuel supply stopping means for stopping fuel supply to the engine by stopping driving at least one of the fuel pump and the injector when the accident determining apparatus determines that an accident occurred, and ignition operation stopping means for stopping any ignition operation of the engine when the accident determining apparatus determines that an accident occurred.

12. The emergency engine shutoff apparatus for ship according to claim 1, wherein

the engine shutting off means in accident is comprised of ignition operation stopping means for stopping an ignition operation of the engine when the accident determining apparatus determines that an accident occurred.