JPH09301275A - Propulsion engine for vessel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To design the shaft strength at a minimum cost by suppressing the over torque generated by the lateral unbalance of transmission torque. SOLUTION: A clutch slip detecting circuit 22a and a torque detecting circuit 22b are integrated into a main engine remote device 22. The torque transmitted to a propeller is regularly detected by a torque detector 21 mounted on an intermediate shaft, and inputted as an electric signal T1 to the torque detecting circuit 22b. Rotation detecting sensors 7a, 7e are mounted on the input shaft and output shaft in a speed reducer, respectively, and the detected values are inputted as electric signals S1, S2 to the slip detecting circuit 22a. When the detected torque exceeds a regulated value, an electric signal E1 is transmitted to an electropneumatic converting valve 23 through a speed setting control circuit so as to reduce the main engine rotating speed, and it acts on a governor 24 after converted into a pneumatic signal A1 to change the main engine rotating speed. Thus, the over torque acting on a propeller shaft can be suppressed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates generally to a propulsion engine of a ship, and more particularly to a transmission torque between two propulsion shafts in a single-shaft twin-shaft ship where the number of main engines is one high-power engine in a twin-shaft ship. The purpose is to control excessive torque resulting from equilibrium.

[0002]

2. Description of the Related Art Regarding a propulsion engine of a ship, a one-machine one-shaft system is generally adopted in which one main engine is connected to one propeller through a propulsion shaft. However, in order to cope with the speeding up of ships, considering the propulsion efficiency together with the adoption of a high-power engine, it is necessary to decrease the propeller speed and increase the outer diameter.

In particular, regarding the outer diameter of the propeller, in order to secure an appropriate submersion rate within a limited hull requirement,
Naturally, there is a limit to the increase in outer diameter, and in order to cope with this, a two-machine twin-screw system is adopted in which there are multiple propellers and the main engine is placed in each.

As a result, the associated equipment including the main engine, the installation onboard the ship, and the increase in the number of outfitting operations will increase the ship price. Further, due to the constraint of the hull shape, the main engine must be arranged near the center which is the bow direction of the hull, so that the volume of the cargo hold is inevitably reduced in a cargo ship.

As a measure to solve these problems, a one-machine two-axis system in which a plurality of propellers are driven by one high-power engine has been devised. Regarding this single-machine, twin-screw system, the purpose of expanding the cargo hold capacity of a cargo ship is disclosed in JP-A-3-132.
497.

As shown in FIG. 7, the main engine 3 is arranged on the center line behind the hull with the output shaft 4 oriented in the bow direction, and the reduction gear 7 is arranged on the bow side of the output shaft 4. Then, the rotational speed of the main engine 3 is reduced and the power is distributed to the left and right shafts. The left and right output shafts of the speed reducer 7 extend toward the stern direction and are connected to the propeller 9 via the intermediate shaft 5a and the propeller shaft 5.

[0007] Normally, the main engine 3 is arranged in the bow direction of the speed reducer 7, whereas in this proposal, the main engine 3 is arranged in the stern direction, and the surplus space is effectively used as the ship's capacity. There is a feature in doing it.

[0008]

When the one-machine two-shaft system is adopted, the power distribution to the left and right propellers is generally performed by a gear device in consideration of the arrangement based on the conventionally practiced technology. is there. In that case, the main engine and the propeller are mechanically coupled, and the power is transmitted to the propeller after being divided into two parts. Therefore, the design strength of the propulsion shaft should be one that can withstand half the output of the main engine. Good.

However, the absorbed horsepower of the propeller changes variously even at the same rotation speed depending on the behavior of the hull. In particular, the absorption horsepower of the left and right propellers is not the same when the propeller is ups and downs during turning and in waves, so that it is conceivable that the transmission torques to the left and right propulsion shafts become unbalanced.

As a result, an excessive torque exceeding the design strength may be applied to one of the propulsion shafts. This torque imbalance is induced by the propeller and cannot be controlled by the main engine itself.

As a countermeasure, it is possible to employ a variable pitch propeller having a variable propeller blade angle and control the blade angle to suppress an increase in torque. Also, use a fixed-pitch propeller with a fixed propeller blade angle, design the strength of the propulsion shaft system on the left and right with transmission torque equivalent to the maximum output of the main engine, and provide sufficient strength against torque imbalance. It is also possible, but neither can be said to be a good idea if manufacturing costs are taken into consideration.

The present invention aims to minimize the manufacturing cost of a propulsion shaft system by suppressing an excessive torque generated by a left-right unbalance of transmission torque in a single-machine / two-shaft type ship using a fixed pitch propeller. To aim.

[0013]

DISCLOSURE OF THE INVENTION A ship propulsion engine according to the present invention is a ship propulsion engine in which an output from a main engine is transmitted to a pair of propeller shafts through a distributor; the distributor and each propeller shaft. A hydraulic clutch and a speed reducer having a reverse rotation function, a means for detecting the axial torque of each propeller shaft, a slip amount detecting means for the clutch, and a rotational speed control means for the main engine. The clutch has hydraulic pressure set so that slip occurs when the axial torque of the propeller shaft is excessive; the rotational speed control means controls the axial torque of the propeller shaft to exceed an upper set value. In this case, the rotational speed of the main engine is decelerated with respect to the command speed from the operation handle, and the decelerated torque of the main engine is incorporated in the governor of the main engine. When the shaft torque falls below the lower set value by limiting to the maximum torque set by the fuel injection amount limiting mechanism, it has the function of canceling deceleration and the clutch slip amount exceeds the set allowable value. In this case, it has a function of decelerating the rotation speed of the main engine to a predetermined speed, and then releasing the deceleration when the slip amount falls within an allowable value. .

With the above structure, first, when the slip amount of the clutch is within the set allowable value and the axial torque of the propeller shaft exceeds the upper set value, the rotational speed of the main engine is changed from the operating handle. The generation of excessive torque is suppressed by decelerating the command speed of. In this case, the torque of the main engine is limited to the maximum torque set by the fuel injection amount limiting mechanism built into the governor. As a result, when the axial torque of the propeller shaft falls below the lower set value, this deceleration control is released and the rotational speed of the main engine is returned to the command speed.

Further, when the above function cannot be followed due to the rapid torque increase and the slip amount of the clutch exceeds the set allowable value, the rotational speed of the main engine is decelerated to a predetermined speed to damage the clutch. To prevent. As a result, when the slip amount of the clutch falls within the set allowable value, the deceleration control is released and the rotation speed of the main engine is returned to the command speed.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An example of an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is an overall configuration diagram showing an example of an embodiment of the present invention. Engine room 2 on the bow side with respect to the hull 1
However, a speed reducer chamber 18 is provided on the stern side.

In the engine room 2, one main engine 3 is arranged with its output shaft 4 facing the stern side. The transmission torque of the main engine 3 is input to the distributor 19 via the connecting shaft 16 penetrating the partition wall 17.

The distributor 19 distributes only the torque to the left and right while keeping the input rotational speed constant, and inputs the torque to the speed reducer 7 via the gear coupling 11. A gear mechanism for reducing the input speed and a pair of hydraulic multi-plate clutches 7c for switching between forward and reverse movements are incorporated in the speed reducer 7. By switching these clutches, the output shaft 7
The direction of rotation of a can be changed to move the ship forward or backward.

The clutch also has a slip function by adjusting the hydraulic pressure, and the output speed can be arbitrarily set in the low speed range in the port. The control method of the output speed is divided into a port speed range and a voyage speed range other than that.

In the low-speed port speed range, the slip amount is gradually changed by adjusting the clutch hydraulic pressure by the slip function while the input speed of the speed reducer 7 is always kept constant, and is set by the operation handle. The target output speed is obtained.

However, the use of the slip function is limited to the speed range in the port. It should be noted that the switching of the clutch between forward and reverse and the control of the output speed by the slip function can be performed independently for the left and right propeller shafts. A ship maneuvering function equivalent to that of the biaxial mechanism has been achieved.

On the other hand, in the voyage speed range, the target output speed set by the operating handle is obtained by changing the input speed while the clutch is in the "fit" state regardless of the slip function. It is designed to be used.

However, in this state, when a rapid increase in torque occurs, the maximum oil pressure value is set so that the clutch slips at a predetermined excessive torque value.
An intermediate shaft 5a and a propeller shaft 5 are connected to the output shaft 7a, and a propeller 9 is fixed to the stern end of the output shaft 7a.

A torque detector 21 is attached to each of the intermediate shafts 5a, and the balanced state of the left and right torques is constantly monitored. A shaft generator 20 is arranged in the center of the stern side of the distributor 19 via a joint 11a so that the necessary electric power in the ship is supplied.

Next, the control block is shown in FIG. As shown in the block diagram, in the main engine remote control device 22, a clutch slip detection circuit 22a and a torque detection circuit 22b are provided.
Is incorporated.

Torque detector 2 mounted on the intermediate shaft 5a
The torque transmitted to the propeller 9 is constantly detected by 1 and is input to the torque detection circuit 22b as an electric signal T1. Further, inside the speed reducer 7, rotation detection sensors 7d and 7e are attached to the input shaft and the output shaft, respectively, and are input as electrical signals S1 and S2 to the slip detection circuit 22a.

When the detected torque exceeds the specified value, the electric signal E1 is sent to the electro-pneumatic conversion valve 23 via the speed setting control circuit so as to decrease the main engine rotation speed, and the air signal A1 is sent. After the conversion, it acts on the governor 24 to change the rotation speed of the main engine.

Here, the output characteristic of the engine will be described with reference to FIG. The output torque of the engine changes according to the number of revolutions along a curve called a ship characteristic. On the other hand, the output torque of the engine depends on the injection amount of fuel, and if the injection amount is constant, the output torque of the engine is almost constant even if the rotation speed changes, and can be approximated to a straight line.

Therefore, when an excessive torque acts on the propulsion shaft due to the torque imbalance, the fuel injection amount, that is, the output torque of the engine decreases and the excessive torque acts on the propulsion shaft by reducing the engine speed. Can be suppressed.

However, with respect to an excessive torque due to a sudden change in the behavior of the hull such as turning, the output torque of the engine can be easily suppressed because the change in the behavior of the hull is delayed even if the engine speed is adjusted. Can be difficult.

Therefore, a reliable torque suppressing method will be described below in which the governor limiting mechanism is also used to regulate the rotational speed and simultaneously limit the fuel injection amount. FIG. 5 shows the fuel injection amount control mechanism 30 of the engine.

The rotation speed of the engine 3 is controlled by the governor 31 assembled to the engine, and the target rotation speed is given to the governor as a governor input signal (air signal) 35. In response to the input air signal 35, the governor drives the fuel pump 32 from the governor output lever 33 via the link mechanism 34 in order to maintain the rotation speed, and adjusts the amount of fuel injected into the engine. .

Next, the governor control mechanism will be described.
In the governor, as shown in FIG. 6, a mechanism for limiting the maximum movable amount of the output value in advance according to the input value of the governor is incorporated.

By setting this limit value, the output value can be suppressed over the entire input range of the governor. As described above, the input and output of the governor correspond to the engine speed and the fuel injection amount (torque), respectively. By changing the governor input as shown in FIG. 4, the engine speed and the fuel injection amount are changed. The upper limit of (torque) can be set at the same time.

Further, by setting the output characteristic of the governor so as to approximate the output characteristic of the engine (property for ship), ideal torque control becomes possible. On the other hand, the slip detection circuit 22
In the case of a, the clutch 7c
When the clutch slips, an alarm signal C1 is sent to the monitor panel monitor 25 as an abnormal slip and a visible and audible alarm is issued, except for the slip control that is normally performed when maneuvering in the port.

Next, FIG. 3 shows the control flow. Normally, the governor controls the rotational speed of the main engine, "engagement" and "disengagement" of the clutch, and slip control in the port through the speed setting control circuit and the clutch control circuit in response to a command from the operating handle.

If either one of the shaft torques is 110% of the specified value (5% of the maximum transmission torque of the main engine).
If the value exceeds 0%), the main engine speed is reduced and the transmission torque is reduced.

When the torque falls below 95% of the specified value, or when the torque difference between the left and right shafts is within 10% and a certain period of time has passed, the governor rotation setting of the instruction is returned while comparing with the operation handle instruction. Speed up.

The increasing / decelerating-continuous control operation is performed based on the result of detecting the torque value every 2 seconds and at the same time monitoring the abnormal slip of the clutch at all times. The control operation for increasing and decelerating is displayed by the indicator lamp as "in torque control".

On the other hand, due to the rapid increase in the shaft torque, even if the fuel injection amount limiting mechanism as described above is used together, the control function based on the above torque cannot be followed, and the shaft of any propeller shaft cannot be followed. The maximum oil pressure of the clutch is set so that the clutch slips and protects the shaft system when the torque exceeds 125% of the specified value.

If the slip due to this excessive torque is left as it is, there is a risk of clutch damage. Therefore, if the slip amount of any one of the clutches exceeds the set allowable value, an alarm is issued as an abnormal slip and at the same time, In order to protect the clutch, a safety function is provided to send an automatic deceleration signal to the speed setting control circuit to decelerate the main engine to a safe low speed range, for example, idling speed.

As a result of the automatic deceleration, if the clutch slip amount falls within the set allowable value, the operation handle is set to "SLOW".
The automatic deceleration state is released by setting the position below.

Further, after the automatic deceleration, if the slip amount of the clutch still does not fall within the allowable value, a signal for releasing the clutch is sent to the clutch control circuit. This signal forces the clutch to "disengage" regardless of the command from the operating handle.

This "detach" signal causes the operation handle to move to "NEUT
It is released by setting it to the "RAL" position. In addition,
An override switch is provided for main engine speed control to suppress excessive torque and automatic deceleration in the case of abnormal clutch slip, and cancels all of these controls and safety functions in an emergency situation where safety of the ship should be prioritized. be able to.

[0045]

As described above, according to the present invention, in the one-machine two-shaft system using the fixed pitch propeller, even if the excessive torque due to the torque imbalance is generated in the left and right propulsion shafts, the proper control of the main engine speed is performed. By controlling the torque increase to the specified value or less, the shaft strength can be designed to be the minimum.

In case of a sudden torque increase, the clutch is slipped and used as a safety device to double protect the propulsion shaft system. As a result, the cost of the entire propulsion mechanism in the ship price can be minimized without employing an expensive propulsion shaft system such as a variable pitch propeller.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a propulsion mechanism according to the present invention.

FIG. 2 is a block diagram showing a configuration of rotation speed control means.

FIG. 3 is a control flow sheet.

FIG. 4 is an explanatory diagram of output characteristics of the engine.

FIG. 5 is an explanatory diagram of an injection fuel control mechanism of the engine.

FIG. 6 is an explanatory diagram of an output limit area corresponding to a governor input.

FIG. 7 is an explanatory view showing an example of a conventional one-machine two-axis propulsion mechanism.

[Explanation of symbols]

3 ... Main engine, 5 ... Propeller shaft, 7 ... Reduction gear, 7c
... hydraulic clutch, 21 ... torque detecting means, 30 ... fuel injection amount control mechanism.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Sadatomo Kuribayashi 2-4-1, Marunouchi, Chiyoda-ku, Tokyo Inside Kei Seven Co., Ltd.

Claims (1)

[Claims] 1. A propulsion engine for a ship, which transmits an output from a main engine to a pair of propeller shafts via a distributor, and is a hydraulic type having a reverse rotation function, which is interposed between the distributor and each propeller shaft. A clutch and a speed reducer, a means for detecting the axial torque of each of the propeller shafts, a slip amount detecting means for the clutch, and a rotational speed control means for the main engine, wherein the clutch is the shaft of the propeller shaft. When the torque is excessive, the hydraulic pressure is set so as to cause the slip, and when the axial torque of the propeller shaft exceeds the upper set value, the rotation speed control means controls the rotation speed of the main engine by an operating handle. From the command speed from
Also, the decelerated torque of the main engine is limited to the maximum torque set by the fuel injection amount limiting mechanism incorporated in the governor of the main engine, and if the shaft torque subsequently falls below the lower set value, the deceleration is performed. When the slip amount of the clutch exceeds the set allowable value, the rotation speed of the main engine is reduced to a predetermined speed, and then the slip amount falls within the allowable value. A propulsion device for a ship, which has a function of releasing deceleration.