JPH0333597Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention is mainly aimed at preventing the main engine from stopping (so-called engine stalling) when operating a forward/reverse clutch to reverse the rotational direction of a ship's propeller. Relating to a stoppage prevention device.

Generally, when a ship is moving forward and it becomes necessary to switch forward or backward to avoid an emergency (clutch astern), the forward/reverse clutch is disengaged and the main engine and propeller side are disconnected. After disengagement, the clutch is inserted with the main engine running at idle speed to switch between forward and forward motion.

However, if the propeller idle torque is large during the clutch stun mentioned above (the propeller rotation speed is high when the clutch is disengaged), if the clutch is engaged in this state, the inertia torque on the propeller side, which is the load, will be reduced. Due to the large size, problems may occur where the main engine stops. This problem is particularly likely to occur in ships equipped with large-diameter propellers.

For this reason, conventionally, when the clutch is disengaged, a speed increase command is automatically given to the main engine governor, and the main engine speed is increased above idling speed so that the main engine torque is greater than the propeller's idling torque. In this case, the clutch is engaged to prevent the main engine from stopping, but in this case, in order to overcome the propeller idle energy and switch the propeller rotation direction without stopping the main engine, the idle rotation It is difficult to properly set or adjust the rotation speed of the main engine when the clutch is engaged, and in the unlikely event that the rotation speed of the main engine is set lower than the appropriate rotation speed when the clutch is engaged, If the rotational energy of the propeller is smaller than the propeller idle energy, the problem of stopping the main engine will still occur.

This invention was made in view of the above circumstances,
When reversing the direction of rotation of a propeller as a load (hereinafter referred to as "load"), the clutch can be engaged easily, and the main engine will not stop and the rotation of the load will be ensured. An object of the present invention is to provide an engine stop prevention device for an internal combustion engine that can switch directions.

In order to achieve the above object, the present invention includes a clutch engagement/disassembly device provided between the main engine and the load;
The rotation speed detector detects the rotation of the main engine, and the output of this rotation speed detector is compared with a predetermined setting value, and if the output of the rotation speed detector is less than the above setting value, A clutch control circuit that opens a contact means whose one end is connected to one end of a power source, and a clutch actuation circuit that is provided between the other end of the contact means and the other end of the power source and is brought into a closed state in response to a clutch insertion command. The present invention is configured to include a command switch means and a clutch electromagnetic valve means for engaging the clutch of the clutch engaging/disengaging device when the clutch operation command switch means is in the closed state.

Hereinafter, one embodiment of the present invention will be described based on the drawings.

Reference numeral 1 in FIG. 1 is the main engine of the ship, and the main engine 1 is equipped with a speed control handle and a governor (not shown). Control is now in place to match the A forward/reverse reducer (clutch engagement/disassembly device) 2 having a built-in clutch (not shown) is connected to the output shaft 1a of the main engine 1. is the propeller (load) via the propulsion shaft 3
4 are connected.

Further, a rotation speed detector 5 such as a tachogenerator is attached to the output shaft 1a of the main engine 1, and the output of this rotation speed detector 5 is input to a clutch control circuit (comparator) 6. A power supply 7 is connected to the clutch control circuit 6, and the power supply 7 causes the clutch control circuit 6 to
compares the value set in advance in the clutch control circuit 6 with the output of the rotation speed detector 5,
When the output of the rotation speed detector 5 is below a set value, the contact (contact means) A is opened. The above set value is set lower than the idle rotation of the main engine 1.

One end of a power source 7 is connected to one end of the contact A, and a forward clutch actuation command switch is connected between the other end of the contact A and the other end of the power source 7, and is closed by a forward clutch engagement command. (Clutch operation command switch means) AH, a forward clutch solenoid valve (clutch solenoid valve means) H that engages the forward clutch, and a reverse clutch operation command switch (clutch operation command switch means) that is closed by a reverse clutch engagement command. A reverse clutch solenoid valve (clutch solenoid valve means) S into which the AS and reverse clutch are fitted is inserted.

When a ship equipped with an internal combustion engine stop prevention device configured as described above suddenly switches to astern for emergency avoidance while moving forward, the forward clutch, which has been engaged until now, must first be disengaged. (time t ₁ in FIG. 2), and the governor controls the rotational speed of the main engine 1 so as to decrease from the forward cruising rotational speed a to the idle rotational speed c. Therefore, the propeller 4 is disconnected from the main engine 1 side, but continues to rotate (idle) in the forward direction as the ship moves forward due to inertia.

In this state, when the rotational speed of the main engine 1 drops to the idle rotational speed c and a reverse clutch engagement command is issued, the reverse clutch operation command switch AS is closed. At this time, the rotation speed of the main engine 1 detected by the rotation speed detector 5 is higher than the set rotation speed d, and the contact A of the clutch control circuit 6 is in the closed state. Current flows through the reverse clutch solenoid valve S by the command switch AS. As a result, the reverse clutch solenoid valve S is energized, the reverse clutch of the forward/reverse speed reducer 2 is engaged, and the main engine 1 and the propeller 4 side are connected. At this time, if the idling energy of the propeller 4 is relatively small, the main engine 1 overcomes the idling torque of the propeller 4 and increases to the reverse speed b as shown by the dashed line in FIG. Therefore, propeller 4
will rotate in the opposite direction, and the ship, which had been moving forward by coasting, will now move astern.

Further, when the idle energy of the propeller 4 is large and the rotational torque of the main engine 1 is smaller than the idle rotation torque of the propeller 4, the rotational speed of the main engine 1 continues to decrease. Then, when the rotation speed becomes lower than the set rotation speed d, the contact A of the clutch control circuit 6 becomes open.
The reverse clutch solenoid valve S is demagnetized, and the reverse clutch of the forward/reverse speed reducer 2 is released. Therefore, the connection between the main engine 1 and the propeller 4 side is released, and the governor controls the rotation speed of the main engine 1 to rise to the idle rotation speed c; When the set rotation speed d is exceeded, the contact A of the clutch control circuit 6 is closed again, so the reverse clutch solenoid valve S is energized, the reverse clutch of the forward/reverse reducer 2 is engaged, and the main engine 1 and propeller 4
The sides are connected.

In this way, the main engine 1 and the propeller 4 side are repeatedly connected and uncoupled by the engagement and disengagement of the reverse clutch of the forward/reverse reducer 2, and when the rotational torque of the main engine 1 overcomes the idle torque of the propeller 4. , as shown by the solid line in FIG. 2, the rotational speed of the main engine 1 increases to the reverse rotational speed b. As a result, the propeller 4 rotates in the opposite direction, and the ship moves smoothly astern without the main engine 1 stopping.

In addition, when switching to forward mode when the vessel is moving astern, the procedure from forward to reverse is the same as described above, so I will not go into details, but in this case, the forward clutch operation command switch is used instead of the reverse clutch operation command switch AS. While AH is closed by command, contact A of clutch control circuit 6 is closed or opened depending on the magnitude relationship between main engine 1 rotation speed and set rotation speed d, and forward clutch solenoid valve H is energized. Alternatively, by being demagnetized and the forward clutch of the forward/reverse speed reducer 2 being engaged and disengaged, the ship moves forward without stopping the main engine 1. In addition, in this embodiment, when the rotation speed of the main engine 1 reaches the set rotation speed d and the clutch is in the disengaged state, the main engine 1
The clutch is engaged when the number of revolutions exceeds the set number of revolutions d again, but a second set number of revolutions (a number of revolutions below the idle revolution) is provided which is higher than the set number of revolutions d. The clutch may be engaged when the rotational speed of the main engine 1 exceeds the second set rotational speed.

In addition, when the propeller 4 is rotating in one direction and the forward/reverse speed reducer 2 is once disengaged, when the propeller 4 is to be rotated in the same direction again, the main engine 1 and the propeller Although the rotational speeds on the 4th side and the 4th side are not equal, such a case can also be dealt with by the above-mentioned engine stop prevention device.

Furthermore, when a transmission is provided between the main engine 1 and the propeller 4, the engine stop prevention described above can also be used if the rotational speeds of the transmission and propeller 4 do not match during a gear change operation. This can be handled with equipment.

As explained above, the present invention includes a clutch engagement/disassembly device provided between the main engine and the load, a rotation speed detector for detecting the rotation of the main engine, and an output of the rotation speed detector. a clutch control circuit that opens a contact means having one end connected to one end of a power source when the output of the rotation speed detector is less than or equal to the set value by comparing it with a predetermined set value; A clutch actuation command switch means is provided between the other end of the means and the other end of the power source and is brought into a closed state by a clutch engagement command, and a clutch of a clutch engagement/disassembly device is engaged in the closed state of the clutch actuation command switch means. Since the structure is equipped with a solenoid valve means for the clutch, the rotation of the load can be reliably and easily switched without stopping the main engine when the clutch is engaged, and a half-clutch state can be completely avoided. There is no need to worry about burning out the clutch or impairing its durability.
Furthermore, in order to shorten the time required for complete engagement of the clutch, it is also possible to electrically limit the number of times the clutch is engaged and disengaged. Moreover, it has excellent effects such as extremely simple structure, easy manufacture and control.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing an embodiment of the present invention;
FIG. 2 is a characteristic diagram showing the change in the rotational speed of the main engine over time when the engine stop prevention device of the present invention is used. 1... Main engine, 2... Forward/reverse speed reducer, 4... Propeller (load), 5... Rotation speed detector, 6... Clutch control circuit (comparator), d... Set rotation speed.

Claims (1)

[Scope of utility model registration request] A clutch engagement/disassembly device 2 provided between the main engine 1 and the load 4, a rotation speed detector 5 for detecting the rotation of the main engine 1, and an output of the rotation speed detector 5 and a predetermined setting. When the output of the rotation speed detector 5 is less than or equal to the set value,
A clutch control circuit 6 that opens a contact means A having one end connected to one end of a power source 7, and a clutch control circuit 6 provided between the other end of the contact means A and the other end of the power source 7,
Clutch operation command switch means AH, AS which are brought into a closed state by a clutch insertion command, and clutch electromagnetic valve means H, S which engage a clutch of a clutch insertion/disassembly device 2 when said clutch operation command switch means AH, AS are in a closed state. An engine stop prevention device for an internal combustion engine, characterized by comprising: