JP5084788B2 - Marine fuel regulator - Google Patents

Description

  The present invention relates to a fuel adjustment device for a ship that adjusts the amount of fuel supplied to an internal combustion engine in accordance with a load fluctuation caused by disturbance such as waves on the water surface during navigation of the ship.

  When a ship such as a cargo ship or a merchant ship navigates the ocean, the rotational speed of the internal combustion engine is controlled so that the ship speed is substantially constant. At this time, even if the main shaft of the internal combustion engine has the same rotation speed, the slip amount of the propeller differs depending on the sea condition and does not always have the same boat speed.Therefore, the operating device is operated by the occupant so that the ship reaches the target boat speed. Thus, the rotational speed of the internal combustion engine is set according to the sea condition.

  When navigating the ship, disturbances such as tidal currents, wind pressure, waves, and swells are applied to the ship, and the load applied to the propeller shaft is increased or decreased by the disturbances. If the load applied to the propeller shaft fluctuates frequently, the rotational speed of the internal combustion engine frequently changes. Therefore, it is necessary to keep the rotational speed of the internal combustion engine constant by adjusting the fuel supplied to the internal combustion engine according to the navigation resistance of the ship, and the ship is provided with a fuel adjustment device, that is, a governor (for example, (See Patent Documents 1 and 2). The governor constantly detects the rotational speed of the internal combustion engine, calculates a deviation from the set rotational speed, and adjusts the fuel supply amount so that the rotational speed of the internal combustion engine becomes the set rotational speed.

JP-A-7-29738 Japanese Patent Laid-Open No. 8-200231

  By the way, the rotational speed of the internal combustion engine used as a control parameter by the governor is determined by the magnitude relationship between the output torque output from the internal combustion engine and the load torque applied to the propeller shaft. It takes a certain time until the balance of the engine is lost and the rotational speed of the internal combustion engine changes. This is because a marine internal combustion engine has not only its own weight but also the mass of a flywheel and a propeller connected to the main shaft, so that these inertial forces are large. In other words, since the governor monitors the rotational speed of an internal combustion engine with a time lag, the load torque may already be in a different state after the change has occurred when signs of a rotational speed change are seen. There is. The governor control frequency is about 20 Hz. For the same reason as described above, after detecting the change in the rotation speed of the internal combustion engine, it takes several seconds until the rotation speed of the internal combustion engine changes after the fuel supply amount is adjusted. A time lag of several tens of seconds is generated from this, and the influence is exerted on the input signal of the next control. For this reason, it is difficult to adjust the fuel supply amount for short-term disturbances that change from moment to moment in the governor characteristics, and when the main shaft speed of the internal combustion engine changes due to short-term disturbances, the governor control frequency However, it is difficult to stably control the spindle speed in response to disturbance.

  In this way, the governor contributes to the control of the rotation speed for medium- to long-term disturbances that change with a period of several hours such as tidal currents and wind pressures, but it takes several seconds to several tens of seconds like waves and swells. It is considered that the rotational speed control against short-term disturbances that change with the period is an unstable factor. Recent actual ship measurement results show that energy-saving effect is recognized by lowering the governor control frequency, and fuel consumption rate deterioration has occurred due to unavoidable speed fluctuations in the control by existing governors. It has been confirmed.

  Therefore, in the conventional marine fuel adjustment device, the output torque of the internal combustion engine is controlled with respect to the load fluctuation of the propeller by adjusting the fuel supply amount to the internal combustion engine by the governor for medium- to long-term disturbances. However, when a short-term disturbance is applied to the ship, it is difficult to control the load applied to the internal combustion engine by the governor.

  The object of the present invention is to prevent the fluctuation of the rotational speed due to the load fluctuation being transmitted to the internal combustion engine when a short-term disturbance such as a wave or swell is applied to the propeller of the ship, and the internal combustion engine by stabilizing the rotational speed. It is to improve the fuel consumption of the car.

  Another object of the present invention is to increase the accuracy of the rotational speed control by capturing the load fluctuation to the propeller at a time point before the rotational speed fluctuation occurs and performing appropriate control promptly.

A marine fuel adjustment device of the present invention is a marine fuel adjustment device that adjusts a fuel supply amount to an internal combustion engine that is connected to a propeller shaft of a propeller that gives propulsive force to the vessel and applies power to the propeller shaft. An internal combustion engine comprising a load detection means for detecting a load applied to the propeller shaft, a rotation speed setting means for setting a set rotation speed of the internal combustion engine, and a rotation speed and output at a constant fuel supply amount in the internal combustion engine. An internal combustion engine characteristic data storage means for storing engine characteristic data; and an appropriate fuel supply amount that produces an output balanced with the load under the set rotational speed based on the internal combustion engine characteristic data; and a fuel supply amount control means for directing a supply amount signal to the engine, the load detecting means includes a thrust detection means for detecting the thrust applied to the propeller shaft, rotational speed of the propeller shaft Storing the thrust coefficient characteristic data for the forward coefficient obtained from the rotational speed detecting means for detecting, the thrust coefficient calculating means for calculating the thrust coefficient from the thrust and the rotational speed, and the inflow speed to the propeller and the rotational speed. Thrust coefficient characteristic data storage means, forward coefficient calculation means for calculating a forward coefficient from the thrust coefficient based on the thrust coefficient characteristic data, torque coefficient characteristic data storage means for storing torque coefficient characteristic data for the forward coefficient A torque coefficient calculating means for calculating a torque coefficient from the forward coefficient based on the torque coefficient characteristic data; and a load torque calculating means for calculating a load torque applied to the propeller shaft from the torque coefficient and the rotation speed. And based on the internal combustion engine characteristic data by the fuel supply amount control means. There are, characterized by calculating a proper fuel supply quantity such that the output torque commensurate with the load torque under the set rotation speed.

  The marine fuel adjustment apparatus according to the present invention averages the load detected by the load detection means for each rotation period of the propeller shaft, and uses the load averaged for each rotation period of the propeller shaft. The supply amount is calculated.

  The fuel adjustment device for a ship according to the present invention includes a governor that calculates an appropriate fuel supply amount from a deviation between the rotational speed of the internal combustion engine and the set rotational speed and sends a supply amount signal to the internal combustion engine. And

  According to the present invention, since the fuel supply amount to the internal combustion engine is adjusted so that the output is balanced with the load applied to the propeller shaft at the set rotational speed, short-term disturbances such as waves and swells. Even when navigating the surface of the water where there is a problem, it is possible to maintain the balance between the load and the output, and to prevent the fluctuation of the load applied to the propeller shaft from being transmitted to the internal combustion engine, thereby preventing the rotational speed of the internal combustion engine from fluctuating. it can. That is, navigation can be performed with the internal combustion engine speed maintained at the set rotational speed, and fuel efficiency can be improved compared to a case where the internal combustion engine speed varies periodically. In addition, since the fluctuation of the load applied to the propeller shaft is captured before the speed of the internal combustion engine fluctuates and the fuel supply amount is controlled before the speed of the internal combustion engine fluctuates, the accuracy of the speed control is improved. It becomes possible to raise. The load torque applied to the propeller shaft includes a method of directly detecting by the torque detecting means and a method of calculating from the thrust applied to the propeller shaft detected by the thrust detecting means and the rotation speed of the propeller shaft.

It is a block diagram which shows the fuel adjustment apparatus of the ship which is one embodiment of this invention. It is a characteristic diagram showing the relationship between the engine output torque and the rotational speed of the main shaft under the condition that the fuel supply amount to the engine is constant. It is a flowchart which shows the procedure of the fuel supply amount control by the fuel adjustment apparatus of the ship shown in FIG. It is a schematic diagram which shows the state which the ship is navigating the water surface which the wave has generate | occur | produced. (A) is a schematic diagram showing a state in which the water surface is changed with respect to the standard water level due to the generation of waves, (B) is a schematic diagram showing changes in ship speed due to the waves, (C) is a diagram showing the change in the waves. It is a schematic diagram which shows the change of the load torque added to a propeller, (D) is a schematic diagram which shows the fuel supply amount to an internal combustion engine in case the load torque fluctuates by a wave compared with the past, (E) It is a schematic diagram which shows the engine speed in case load torque fluctuates by a wave compared with the past. It is a block diagram which shows the fuel adjustment apparatus of the ship which is other embodiment of this invention. It is a characteristic diagram which shows the thrust coefficient characteristic which shows the relationship between the forward coefficient of a propeller, and a thrust coefficient. It is a characteristic diagram which shows the torque coefficient characteristic which shows the relationship between the forward coefficient of a propeller, and a torque coefficient. It is a flowchart which shows the procedure of the fuel supply amount control by the fuel adjustment apparatus of the ship shown in FIG. It is a block diagram which shows the fuel adjustment apparatus of the ship which is further another embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. As shown in FIG. 1, a propeller shaft 12 provided with a propeller 11 that applies thrust to a ship is connected to a main shaft of an engine, that is, an internal combustion engine 13, and the propeller 11 is connected to the internal combustion engine 13 via the propeller shaft 12. The output torque is transmitted. The output torque of the internal combustion engine 13, that is, the net output, is the torque output from the main shaft of the internal combustion engine 13 by subtracting the friction loss in the cylinder, and is also called braking torque. However, there is a type in which the propeller shaft 12 and the main shaft of the internal combustion engine 13 are connected via a reduction gear.

  In order to set the rotation speed of the main shaft of the internal combustion engine 13, the operation device 14 as the rotation speed setting means is provided with an operation handle 14a, and the internal combustion engine 13 inputted by the occupant operating the operation handle 14a. A command signal S1 for the set rotational speed is sent to the controller 15.

  In order to detect the load torque applied to the propeller shaft 12 and the rotation speed of the propeller shaft 12 during navigation of the ship, the propeller shaft 12 is provided with a shaft torque meter 16 as load torque detection means and rotation speed detection means. The load torque in the rotational direction applied to the propeller shaft 12 is detected by a strain gauge 17 attached to the propeller shaft 12, and a detection signal is transmitted from the strain gauge 17 to the shaft torque meter 16 by a radio signal. . The strain gauge 17 transmits a detection signal corresponding to the torsional stress applied to the propeller shaft 12 to the shaft torque meter 16 at a cycle of, for example, 500 Hz. Under the state where the propeller shaft 12 is rotating at a substantially constant rotational speed, when a disturbance such as waves on the water surface or undulation is applied to the propeller 11 and the load torque fluctuates, the torsional stress of the propeller shaft 12 changes. A load torque applied to the propeller shaft 12 can be detected by a signal from the strain gauge 17. However, in order to detect the load torque, an optical shaft torque meter may be used instead of the strain gauge 17.

  The number of revolutions of the propeller shaft 12 is such that light is emitted from the light emitting element provided on the shaft torque meter 16 to the reflecting member 18 provided in a spot manner in the circumferential direction of the propeller shaft 12, and is reflected from the reflecting member 18. Is detected by a light receiving element provided on the axial torque meter 16. However, the shaft torque meter 16 is provided with a light emitting element that irradiates light parallel to the propeller shaft 12 and a light receiving element that detects light reception, and a light-shielding projection that blocks the light beam at a certain rotation angle or a hole-like mechanism that allows light to pass through. It may be a device that detects the number of rotations by providing it around an axis. Further, the rotational speed of the propeller shaft 12 may be detected by detecting the rotational speed of the main shaft of the internal combustion engine 13.

  The shaft torque meter 16 sends a signal S2 including a torque signal corresponding to the load torque from the strain gauge 17 and a rotation speed signal from the light receiving element to the controller 15. The controller 15 includes a filter unit 20 that averages the torque value for each rotation period of the propeller shaft 12 and cancels the peak value by using the rotation speed signal as a trigger. The filter unit 20 causes the propeller shaft 12 to rotate every rotation. The torque signal S3 of the load torque that is averaged is sent to the fuel supply amount calculation unit 21. In addition, a command signal S1 of the set rotational speed of the internal combustion engine 13 set by the operating device 14 is sent to the fuel supply amount calculation unit 21.

  The controller 15 is provided with an internal combustion engine characteristic data storage unit 22 that stores internal combustion engine characteristic data corresponding to the output torque and the rotational speed when the fuel supply amount in the internal combustion engine 13 is constant. Based on the internal combustion engine characteristic data, the fuel supply amount calculation unit 21 produces an output torque that balances the load torque applied to the propeller shaft 12 from the torque signal S3 under the set rotational speed from the command signal S1. An appropriate fuel supply amount is calculated. A supply amount signal S4 corresponding to the appropriate fuel supply amount is sent from the fuel supply amount calculation unit 21 to the internal combustion engine 13, and the fuel to the internal combustion engine 13 is set so that the rotational speed of the main shaft of the internal combustion engine 13 becomes the set rotational speed. The supply amount is controlled.

  The controller 15 includes a microprocessor (CPU) that performs arithmetic processing based on signals from the operating device 14 and the shaft torque meter 16, a memory (ROM) that stores arithmetic programs, map data, arithmetic expressions, and the like, and temporarily It has a memory (RAM) for storing data. As seen in FIG. 1, the controller 15 includes a filter unit 20, a fuel supply amount calculation unit 21, and an internal combustion engine characteristic data storage unit 22, and the fuel supply amount calculation unit 21 uses the internal combustion engine. The fuel supply amount control means for controlling the fuel supply amount to 13 is comprised.

  FIG. 2 is a characteristic diagram showing the relationship between the output torque of the engine and the rotational speed of the main shaft under the condition that the fuel supply amount to the engine is constant. This characteristic diagram shows the characteristics of a diesel engine used as the internal combustion engine 13. The internal combustion engine 13 has the characteristics shown in FIG. 2 in the relationship between the output torque and the rotational speed under a constant supply fuel. doing. In FIG. 2, reference signs “a” to “e” indicate fuel supply amounts, respectively, and the fuel supply amount decreases from the reference signs a to e. In a region where the output torque decreases to the right with the supplied fuel constant, for example, even if the rotational speed temporarily decreases from the operating point A, the rotational speed increases over time due to the increase in the output torque and reaches the operating point A. Even if the rotational speed temporarily increases from the operating point A, the rotational speed will eventually decrease and return to the operating point A due to the decrease in the output torque, and stable output characteristics can be obtained. During steady navigation of the ship, the internal combustion engine 13 is driven in a region where the output torque decreases to the right. In the internal combustion engine characteristic data storage unit 22, in the characteristic diagram shown in FIG. 2, the relationship between the output torque and the rotational speed for all the fuel supply amounts to be calculated is expressed in the form of map data or calculation formulas. Stored as data.

For example, in FIG. 2, when the load torque Q ₁ is applied to the propeller shaft 12 due to waves or undulations when the internal combustion engine 13 is set to the set rotational speed n _t , the internal combustion engine stored in the characteristic data storage unit 22. Based on the characteristic data, an appropriate fuel supply amount indicated by symbol b is calculated so that the output torque of the internal combustion engine 13 is balanced with the load torque Q ₁ applied to the propeller shaft 12 under the set rotational speed n _t . The internal combustion engine 13 is supplied with fuel according to the appropriate fuel supply amount, and an output torque commensurate with the load torque Q ₁ applied to the propeller shaft 12 is transmitted from the main shaft to the propeller shaft 12, so that the rotational speed of the internal combustion engine 13 is increased. It is controlled so as to be the set rotational speed n _t .

  FIG. 3 is a flowchart showing a procedure of fuel supply amount control by the marine fuel adjustment device shown in FIG. During the navigation of the ship, the load torque applied to the propeller shaft 12 and the rotation speed of the propeller shaft 12 are detected by the shaft torque meter 16 (step S1), and signals corresponding to each are sent to the filter unit 20. The load torque signal is sent to the filter unit 20 at a cycle of, for example, 500 Hz, and the rotation speed signal is sent to the filter unit 20 every 0.5 seconds if the propeller shaft 12 rotates at 120 rpm, for example. The filter unit 20 averages all the load torques sent from the shaft torque meter 16 until the propeller shaft 12 makes one rotation for every rotation of the propeller shaft 12 using the rotation speed signal as a trigger. A load torque for each rotation is calculated (step S2). In the internal combustion engine 13, the propeller shaft 12 vibrates due to an impact at the time of combustion for each piston or a fluid fluctuation for each propeller, so that the load torque fluctuates during one rotation of the propeller shaft 12. The value can be canceled by averaging the load torque for each rotation period of the propeller shaft 12. Thereby, a flow field fluctuation | variation can be caught quickly with the period which causes a wave etc.

  A command signal corresponding to the set rotational speed is sent from the operating device 14 to the controller 15, and the fuel supply amount calculation unit 21 reads the set rotational speed of the internal combustion engine 13 in step S3 and calculates an appropriate fuel supply amount. (Step S4). The appropriate fuel supply amount is obtained by reading the internal combustion engine characteristic data stored in the internal combustion engine characteristic data storage unit 22 based on the load torque for each rotation of the propeller shaft 12 and the set rotational speed of the internal combustion engine 13 as described above. Calculated. A supply amount signal is sent to the internal combustion engine 13 based on the appropriate fuel supply amount, and the fuel supply amount to the internal combustion engine 13 is controlled (step S5).

  FIG. 4 is a schematic diagram showing a state where a ship is navigating the water surface where waves are generated. As shown in FIG. 4, if the ship is navigating in the direction indicated by the arrow on the water surface, the ship is in a state S2 in which the wave goes up from a state S1 in which the wave goes up, and in a state S3 in which the wave goes down. Then, the wave reaches the lowest point state S4. When a ship navigates under a state where periodic waves are generated, such a navigation state is periodically repeated.

  FIG. 5 (A) is a schematic diagram showing a state where the water surface is changed with respect to the standard water level due to the generation of waves, and FIG. 5 (B) is a schematic diagram showing changes in ship speed due to the waves. (C) is a schematic diagram showing a change in load torque applied to the propeller by a wave, and FIG. 5 (D) is a schematic diagram showing the amount of fuel supplied to the internal combustion engine when the load torque fluctuates due to the wave as compared with the conventional one. FIG. 5 (E) is a schematic diagram showing the engine speed when the load torque fluctuates due to waves compared with the conventional one.

  When the ship is in a state S1 where the ship reaches the wave and rises, the navigation resistance applied to the hull increases and the ship speed decreases. Since the inflow speed of the water flowing toward the propeller 11 is also reduced due to the decrease in the ship speed, the load torque applied to the propeller shaft 12 via the propeller 11 is increased. The load torque becomes maximum in the vicinity of the state S2 in which the ship navigates the peak of the wave where the boat speed is the lowest. On the other hand, after passing the top of the wave, the navigation resistance caused by the wave decreases at a stretch, the gravitational acceleration is also added, the ship speed increases rapidly, and the load torque decreases. Therefore, when a wave is generated on the water surface when the ship navigates, the ship speed and the load torque change as shown in FIGS. 5 (B) and 5 (C). However, changes in ship speed and load torque are schematically shown in FIGS. 5B and 5C, and the phases of ship speed and load torque with respect to actual wave changes are illustrated. More complicated phase difference.

  When the fluctuation of the load torque applied to the propeller shaft 12 is detected by the shaft torque meter 16, the signal is sent to the controller 15 so that the output torque of the internal combustion engine 13 matches the load torque at the set rotational speed. An appropriate fuel supply amount is calculated, and the fuel supply amount to the internal combustion engine 13 is controlled. Therefore, when the load torque applied to the propeller shaft 12 increases, the amount of fuel supplied to the internal combustion engine 13 increases, and when the load torque applied to the propeller shaft 12 decreases, the amount of fuel supplied to the internal combustion engine 13 decreases and the internal combustion engine 13 is reduced. The fuel supply amount changes as shown in FIG. As a result, the fluctuation in the rotational speed of the internal combustion engine 13 caused by the balance between the load torque applied to the propeller shaft 12 and the output torque of the internal combustion engine 13 is prevented, and as shown in FIG. The number of rotations can be maintained at the set number of rotations.

  Thus, in the present invention, the fuel supply amount to the internal combustion engine 13 is adjusted so that the output torque is commensurate with the load torque applied to the propeller shaft 12 under the set rotational speed. Even when navigating a water surface where a short-term disturbance such as swell occurs, the balance between the load torque and the output torque is maintained, and the load fluctuation applied to the propeller shaft 12 is transmitted to the internal combustion engine 13 to transmit the internal combustion engine 13. Can be prevented from fluctuating. That is, since it is possible to navigate in a state where the rotation speed of the internal combustion engine 13 is maintained at the set rotation speed, fuel consumption can be improved compared to a case where the rotation speed of the internal combustion engine 13 varies periodically. Further, since the fluctuation of the load torque applied to the propeller shaft 12 is captured before the rotation speed of the internal combustion engine 13 fluctuates and the fuel supply amount is controlled before the rotation speed of the internal combustion engine 13 fluctuates, the rotation speed The accuracy of control can be increased.

  On the other hand, if the speed of the internal combustion engine 13 is detected by the governor and the amount of fuel supplied to the internal combustion engine 13 is controlled according to the deviation from the set speed as in the prior art, FIG. , (E), the fuel supply amount is adjusted in accordance with fluctuations in the rotational speed of the internal combustion engine 13. In this case, there is a time lag T until the balance between the output torque and the load torque is lost and the rotational speed of the internal combustion engine 13 fluctuates, and the fuel supply amount is adjusted after detecting the rotational speed fluctuation of the internal combustion engine 13. Since more time is required until the rotational speed of the internal combustion engine 13 changes, it is difficult to stably maintain the rotational speed of the internal combustion engine 13 at the set rotational speed against short-term disturbances. Therefore, the rotational speed of the internal combustion engine 13 frequently fluctuates, and fuel consumption is deteriorated. However, the changes in the fuel supply amount and the engine speed in the prior art in FIGS. 5 (D) and 5 (E) are shown schematically by simply adjusting the fuel supply amount in accordance with the fluctuations in the engine speed. Actually, since the engine speed and the fuel supply amount influence each other, a more complicated phase than that shown in the figure is drawn.

  FIG. 6 is a block diagram showing a marine fuel adjustment apparatus according to another embodiment of the present invention, and FIG. 7 is a characteristic diagram showing a thrust coefficient characteristic indicating a relationship between a propeller forward coefficient and a thrust coefficient. FIG. 8 is a characteristic diagram showing a torque coefficient characteristic indicating a relationship between a propeller forward coefficient and a torque coefficient.

  In the embodiment described above, the load torque applied to the propeller shaft 12 is directly detected by the shaft torque meter 16, whereas in the embodiment shown in FIG. This thrust is detected, and the load torque applied to the propeller shaft 12 is calculated using this thrust value.

  In order to detect the thrust applied to the propeller shaft 12 and the rotation speed of the propeller shaft 12 during navigation of the ship, the propeller shaft 12 is provided with a thrust detector 30 as a thrust detection means and a rotation speed detection means. Thrust applied to the propeller shaft 12 is detected from a plurality of strain gauges 17 mounted obliquely with respect to the main shaft of the propeller shaft 12 or a plurality of strain gauges 17 mounted in the axial direction and the circumferential direction. Obtained by calculation, a detection signal is transmitted from the strain gauge 17 to the thrust meter 30 by a radio signal. However, in order to detect the thrust applied to the propeller shaft 12, a thrust sensor composed of a load cell or the like is provided at the abutting portion contacting the radial surface provided on the propeller shaft 12, and the detection signal of this thrust sensor is used as a thrust meter. You may make it send.

  The rotational speed of the propeller shaft 12 is the same as that of the shaft torque meter 16. Light is emitted from a light emitting element provided in the thrust meter 30 with respect to the reflecting member 18 provided in a spot manner in the circumferential direction of the propeller shaft 12. It is detected by irradiating and detecting reflected light from the reflecting member 18 by a light receiving element provided in the thrust meter 30. However, the thrust meter 30 is provided with a light emitting element that irradiates light in parallel with the propeller shaft 12 and a light receiving element that detects light reception, and a light-shielding protrusion that shields the light beam at a certain rotation angle or a hole-like mechanism through which light passes. It may be a device that detects the number of rotations by providing it around. Further, the rotational speed of the propeller shaft 12 may be detected by detecting the rotational speed of the main shaft of the internal combustion engine 13.

  From the thrust meter 30, a signal S 5 including a thrust signal corresponding to the thrust value from the strain gauge 17 and a rotation speed signal from the light receiving element is sent to the controller 15. The controller 15 has a filter unit 20 that cancels the peak value by averaging the thrust value for each rotation period of the propeller shaft 12 using the rotation speed signal as a trigger. The filter unit 20 causes the propeller shaft 12 to rotate every rotation. Then, a signal S6 including the thrust signal and the rotation speed signal averaged to each other is sent to the thrust coefficient calculation unit 31.

As shown in FIG. 7, the index indicating the propeller performance includes a thrust coefficient K _{T using} the thrust T applied to the propeller shaft 12 and the rotation speed n of the propeller shaft 12 as variables, and water in the flow field to the propeller 11. There is a forward coefficient J with the inflow velocity Va and the rotation speed n of the propeller shaft 12 as variables. The thrust coefficient _KT is a dimensionless value expressed by the following equation (1), and can be calculated from the thrust T applied to the propeller shaft 12 and the rotation speed n of the propeller shaft 12. Further, the forward coefficient J is a dimensionless value represented by the following equation (2). In these equations, D represents the outer diameter of the propeller 11, and ρ represents the viscosity of water. The thrust coefficient calculation unit 31 calculates the thrust coefficient K _T1 from the signal S6 corresponding to the thrust T ₁ applied to the propeller shaft 12 and the rotation speed n ₁ of the propeller shaft 12 based on the equation (1).
K _T = T / (ρn ² D ⁴ ) (1)
J = Va / (nD) (2)

The thrust coefficient _KT has a certain correspondence with the forward coefficient J as shown in the thrust coefficient characteristic diagram of FIG. The controller 15, and the thrust coefficient characteristic data storage unit 32 is provided for storing a value, that the thrust coefficient characteristics data of the thrust coefficient K _T corresponding to the forward coefficient J, the thrust coefficient characteristic data as shown in FIG. 7 map It is stored in the thrust coefficient characteristic data storage unit 32 in the form of data or arithmetic expressions. A signal S7 corresponding to the thrust coefficient K _T1 and the rotation speed n ₁ is sent from the thrust coefficient calculation unit 31 to the advance coefficient calculation unit 33, and the advance coefficient J ₁ is calculated based on the thrust coefficient characteristic data.

Further, as shown in FIG. 8, another index indicating the propeller performance includes a load torque Q applied to the propeller shaft 12 and a torque coefficient K _q using the rotation speed n of the propeller shaft 12 as variables. The torque coefficient K _q is a dimensionless value expressed by the following equation (3), and as shown in the torque coefficient characteristic diagram of FIG. 8, the forward coefficient is similar to the thrust coefficient characteristic diagram shown in FIG. It has a certain correspondence with J. The controller 15 is provided with a torque coefficient characteristic data storage unit 34 for storing the value of the torque coefficient K _q corresponding to the forward coefficient J, that is, the torque coefficient characteristic data, and the torque coefficient characteristic data as shown in FIG. It is stored in the torque coefficient characteristic data storage unit 34 in the form of data or arithmetic expressions. A signal S8 corresponding to the forward coefficient J ₁ and the rotational speed n ₁ is sent from the forward coefficient calculating section 33 to the torque coefficient calculating section 35, and the torque coefficient K _q1 is calculated based on this torque coefficient characteristic data.
K _q = Q / (ρn ² D ⁵ ) (3)

When the torque coefficient K _q1 torque coefficient calculation unit 35 is calculated, the signal S9 corresponding to the torque coefficient K _q1 and the rotational speed n ₁ is transmitted from the torque coefficient calculation unit 35 to the load torque calculating unit 36. The load torque calculation unit 36 calculates the load torque Q ₁ applied to the propeller shaft 12 from the signal S9 corresponding to the torque coefficient K _q1 and the rotation speed n ₁ of the propeller shaft 12 based on the equation (3).

The fuel supply quantity calculating section 21, together with the torque signal S10 sent corresponding from the load torque calculation unit 36 to the load torque Q _1, the command signal S1 corresponding to the setting rotational speed n _t from the operation unit 14 is transmitted. From the torque signal S10 and the command signal S1, the fuel supply amount calculation unit 21 sets the set rotation based on the internal combustion engine characteristic data stored in the internal combustion engine characteristic data storage unit 22 as in the embodiment shown in FIG. An appropriate fuel supply amount is calculated such that the output torque is balanced with the load torque Q ₁ applied to the propeller shaft 12 under the number n _t . A supply amount signal S4 corresponding to the appropriate fuel supply amount is sent from the fuel supply amount calculation unit 21 to the internal combustion engine 13, and the fuel to the internal combustion engine 13 is set so that the rotational speed of the main shaft of the internal combustion engine 13 becomes the set rotational speed. The supply amount is controlled.

  FIG. 9 is a flowchart showing a procedure of fuel adjustment control by the marine fuel adjustment device shown in FIG. During navigation of the ship, the thrust meter 30 detects the thrust applied to the propeller shaft 12 and the rotation speed of the propeller shaft 12 (step S1), and sends a signal corresponding to each to the filter unit 20. The filter unit 20 averages all the thrust values sent from the thrust meter 30 until the propeller shaft 12 makes one revolution for each revolution of the propeller shaft 12 using the rotation speed signal as a trigger. A thrust for each rotation is calculated (step S2). Thereby, the peak value resulting from the impact at the time of combustion for each piston or the fluid fluctuation for each propeller can be canceled, and the flow field fluctuation can be quickly captured in a cycle caused by waves or the like.

  When the thrust coefficient is calculated from the thrust applied to the propeller shaft 12 and the rotation speed of the propeller shaft 12 based on the equation (1) by the signal sent from the filter unit 20 (step S3), the forward coefficient is calculated in step S4. calculate. The forward coefficient is calculated from the thrust coefficient by reading the thrust coefficient characteristic data stored in the thrust coefficient characteristic data storage unit 32. Similarly, the torque coefficient is calculated from the forward coefficient by reading the torque coefficient characteristic data stored in the torque coefficient characteristic data storage unit 34 (step 5). When the torque coefficient is obtained, the load torque applied to the propeller shaft 12 can be calculated from the rotational speed of the propeller shaft 12 based on the equation (3) (step S6).

  A command signal corresponding to the set rotational speed is sent from the operating device 14 to the controller 15, and the fuel supply amount calculation unit 21 reads the set rotational speed of the internal combustion engine 13 in step S7 and calculates an appropriate fuel supply amount. (Step S8). The appropriate fuel supply amount is calculated by reading the internal combustion engine characteristic data stored in the internal combustion engine characteristic data storage unit 22 based on the load torque applied to the propeller shaft 12 and the set rotational speed of the internal combustion engine 13 as described above. . A supply amount signal is sent to the internal combustion engine 13 based on the appropriate fuel supply amount, and the fuel supply amount to the internal combustion engine 13 is controlled (step S9).

  Thus, in the present embodiment, the thrust meter 30 detects the thrust applied to the propeller shaft 12 and the rotation speed of the propeller shaft 12, and calculates the load torque applied to the propeller shaft 12 from these detected values. I have to. Of course, in this embodiment, the same effects as those of the embodiment shown in FIG. 1 can be obtained. However, the load torque applied to the propeller shaft 12 is directly detected by the shaft torque meter 16, and the load torque applied to the propeller shaft 12 is determined from the thrust applied to the propeller shaft 12 detected by the thrust meter 30 and the rotation speed of the propeller shaft 12. It is good also as embodiment which uses together the method to calculate.

  FIG. 10 is a block diagram showing a marine fuel adjustment apparatus according to still another embodiment of the present invention. In the case shown in FIG. 10, the existing governor 40 is used in combination with the marine fuel adjustment device shown in FIG. The governor 40 is supplied with a set rotational speed command signal S11 from the operating device 14 and a rotational speed signal S12 from the internal combustion engine 13, and from the deviation between the rotational speed of the internal combustion engine 13 and the set rotational speed, The appropriate fuel supply amount is calculated so that the number of revolutions becomes the set number of revolutions. A supply amount signal S13 corresponding to the appropriate fuel supply amount is sent from the governor 40 to the internal combustion engine 13, and the fuel supply amount to the internal combustion engine 13 is controlled.

  In the case where the ship sails normally at a substantially constant rotation, the fuel adjustment device for the ship shown in FIG. At this time, since the controller 15 is controlled so that the rotational speed of the internal combustion engine 13 is always maintained at the set rotational speed, the operating frequency of the governor 40 is basically reduced, and the operating threshold of the governor 40, that is, By increasing the deviation amount between the rotational speed of the internal combustion engine 13 and the set rotational speed for the governor 40 to operate, the control by the controller 15 and the control by the governor 40 are overlapped so that the rotational speed is not stable. I try to prevent it. That is, the governor 40 is operated in an auxiliary manner in the event that there is a large difference between the rotational speed of the internal combustion engine 13 and the set rotational speed due to a malfunction of the controller 15 or the like. However, the governor 40 may be used together with the marine fuel adjustment device shown in FIG.

  The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention. For example, in the filter unit 20, the load torque is averaged for each rotation cycle of the propeller shaft 12. However, for each rotation cycle, the load torque may be averaged for every integer rotation cycle such as every two rotations. .

DESCRIPTION OF SYMBOLS 11 Propeller 12 Propeller shaft 13 Internal combustion engine 14 Operating device (rotation speed setting means)
14a Operation handle 15 Controller 16 Shaft torque meter (load detection means, load torque detection means, rotation speed detection means)
17 Strain gauge 18 Reflecting member 20 Filter unit 21 Fuel supply amount calculation unit (fuel supply amount control means)
22 Internal combustion engine characteristic data storage (internal combustion engine characteristic data storage means)
30 Thrust meter (load detection means, thrust detection means, rotation speed detection means)
31 Thrust coefficient calculation unit (Thrust coefficient calculation means)
32 Thrust coefficient characteristic data storage unit (thrust coefficient characteristic data storage means)
33 Advance coefficient calculation unit (advance coefficient calculation means)
34 Torque coefficient characteristic data storage unit (torque coefficient characteristic data storage means)
35 Torque coefficient calculation unit (torque coefficient calculation means)
36 Load torque calculation unit (load torque calculation means)
40 Governor

Claims (3)

A fuel adjustment device for a ship that adjusts a fuel supply amount to an internal combustion engine that is connected to a propeller shaft of a propeller that gives propulsion power to the ship and applies power to the propeller shaft,
Load detecting means for detecting a load applied to the propeller shaft;
A rotation speed setting means for setting a set rotation speed of the internal combustion engine;
Internal combustion engine characteristic data storage means for storing internal combustion engine characteristic data of the rotational speed and output under a constant fuel supply amount in the internal combustion engine;
Based on the internal combustion engine characteristic data, a fuel supply amount control means for calculating an appropriate fuel supply amount so as to achieve an output balanced with the load under the set rotational speed and sending a supply amount signal to the internal combustion engine; Have
The load detecting means includes
Thrust detecting means for detecting thrust applied to the propeller shaft;
A rotational speed detecting means for detecting the rotational speed of the propeller shaft;
Thrust coefficient calculating means for calculating a thrust coefficient from the thrust and the rotational speed;
Thrust coefficient characteristic data storage means for storing thrust coefficient characteristic data for a forward coefficient determined by the inflow speed into the propeller and the rotational speed;
A forward coefficient calculating means for calculating a forward coefficient from the thrust coefficient based on the thrust coefficient characteristic data;
Torque coefficient characteristic data storage means for storing torque coefficient characteristic data for the forward coefficient;
Torque coefficient calculating means for calculating a torque coefficient from the forward coefficient based on the torque coefficient characteristic data;
Load torque calculation means for calculating a load torque applied to the propeller shaft from the torque coefficient and the rotation speed;
An appropriate fuel supply amount is calculated by the fuel supply amount control means based on the internal combustion engine characteristic data so as to obtain an output torque commensurate with the load torque based on the set rotational speed . Fuel conditioner. 2. The ship fuel regulating device according to claim 1 , wherein the load detected by the load detecting means is averaged for each rotation period of the propeller shaft, and the load averaged for each rotation period of the propeller shaft is used. A fuel adjustment device for a ship, which calculates an appropriate fuel supply amount. The marine fuel adjustment device according to claim 1 or 2 , further comprising a governor that calculates an appropriate fuel supply amount from a deviation between the rotational speed of the internal combustion engine and the set rotational speed and sends a supply amount signal to the internal combustion engine. A fuel regulating device for a ship, characterized in that

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