JPS61190136A - Automatic avoiding device of dangerous rotational range of twist vibration for main engine of ship - Google Patents

Abstract

PURPOSE:To improve safety to twist vibration of a main engine by installing a crank shaft twist vibration amplitude measuring sensor to the front side of the engine and interlocking the sensor with an electronic governor. CONSTITUTION:A fuel injection pump 4 and an electronic governor actuator 5 are installed on a main engine 1, and the actuator 5 is connected to a control device 6. A twist vibration amplitude measuring sensor 8 is mounted facing to a crank shaft 7 of the front portion of the main engine 1. The sensor 8 is interlocked with the electronic governor 5 and instruction of fuel increase or fuel decrease is given to the electronic governor 5 in the case of the amplitude of twist vibration over a certain level. Thus, safety to twist vibration of the main engine can be improved more.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an automatic torsional vibration dangerous rotation range avoidance device for a marine main engine.

(Prior art) Currently, in general, in marine main engines, in order to avoid dangerous rotation ranges due to torsional vibration, a method is adopted in which the critical rotation range is displayed in color and indicated in mm length on the machine lN1IIn1 dial on the instrument panel. . However, in that case, it would be left to the will of the chief engineer, which had the drawback of lacking reliability.

(Purpose of the Invention) When a user arbitrarily selects an engine rotation speed (ship speed), the resonance rotation speed of the engine's torsional vibration may sometimes occur. The purpose of this system is to automatically avoid the occurrence of vibrations in the main engine, thereby ensuring safety against torsional vibrations of the main engine.

(Structure of the Invention) The present invention is equipped with a crankshaft torsional vibration amplitude measurement sensor on the front side of the engine [this sensor is linked to an electronic governor, and when the torsional vibration exceeds a certain level, a command is sent to the electronic governor to increase or decrease fuel. This is an automatic torsional vibration dangerous rotation range avoidance device for a marine main engine, which is characterized in that it gives

(Embodiment) In FIG. 1, 1 is a main engine, 2 is a clutch, and 3 is a propeller. The main engine 1 is equipped with a fuel injection pump 4 and an electronic governor actuator 5. The actuator 5 is connected to a control device 6 and operates according to a signal from the control device 6 to inject fuel into the main engine 1. can be controlled.

Crankshaft 7 at the front (anti-flyboil side) of the main engine 1
Torsional vibration measurement sensor (electromagnetic pickup) 8 facing
is installed, and this electromagnetic pickup 8 is connected to the control device 6.
The engine speed and torsion amplitude signals are supplied to the Reference numeral 9 is an accelerator installed in the engine operator IIi seat, etc., and is connected to the control device 6. By operating this accelerator 9 to increase or decrease, Liu 1f- can set the desired engine rotation speed (ship speed). J: The sea urchin has become a sea urchin.

Figure 2 is a state diagram of torsional vibration of the engine. For example, the torsional amplitude is 0.
．． Dangerous rotation range R1 (4th, 5th order), R2 (3rd order) exceeding 3°
, 5th order), the control device 6 is configured as follows in the first embodiment.

That is, in the control device 6 of FIG.
The pulse signal supplied to the control device 6 is frequency-analyzed, the amplitude is calculated for each order, and the value of this value (for example, 0.
A function is provided to instruct the electronic governor actigoator 5 to change the engine speed until the engine speed becomes 3° or less. When the engine speed enters the dangerous speed range R1 or 1)2, the judgment as to whether to increase or decrease the engine speed is made by passing the torsion amplitude signal through a differentiating circuit and determining the change in the speed. Analyze whether the rate of change in torsional amplitude is 1-+J (increasing) or "-", and if it is -, reduce the number of rotations, and if it is -, increase the number of rotations. Assemble the control I device 6. By doing this, the dangerous rotation ranges R1 and R2 in Fig. 2 are determined by the present invention when the torsional amplitude becomes 0.3° or more when the user happens to select that range as the ta function rotation speed (vessel speed). The engine speed is automatically moved out of the dangerous speed ranges R1 and R2.

Further, when the engine speed is set to a range other than the dangerous rotation ranges R1 and R2 or to the rated rotation speed, there is an advantage that the engine speed can quickly avoid the dangerous rotation ranges R1 and R2.

As a second embodiment, the control I device 6 can also be configured as follows. That is, a critical rotational speed range for torsional vibration is input to the control device 6 in advance, and a command is given to the electronic governor actuator 5 to increase or decrease the rotational speed within this range depending on the contents of the input. Further, outside this rotation speed range, the actuator 5 is configured to give a command according to the user-instructed rotation speed (accelerator position).

Specifically, as shown in Fig. 3, the dangerous rotation ranges R1 and R2 are input into the control device 6 in advance. It is preset to issue a command to decrease the engine speed, and to command an increase in engine speed in the high range H1. However, the engine speed varies depending on the engine model and specifications, so manual labor is required depending on the model and specifications.

(Effects of the Invention) As explained above, in the present invention, a torsional vibration amplitude measurement sensor (electromagnetic pickup 8) is attached to the front side of the engine, and this is linked to the electronic governor 5, and if the torsional vibration amplitude exceeds a certain level, an electronic Give a command to increase or decrease fuel to the governor 5,
Even if the user sets the accelerator 9 to a certain dangerous rotational speed, the dangerous rotational speed range can be automatically avoided and the rotational speed closest to the user-instructed rotational speed can be maintained. As a result, even when passing through a dangerous rotation range due to an increase or decrease in ship speed, it is possible to quickly pass through the dangerous rotation range, and it is possible to further improve safety against torsional vibration of the main engine.

[Brief explanation of the drawing]

FIG. 1 is a schematic side view of a device according to the present invention, and FIGS. 2 and 3 are graphs showing the relationship between torsional amplitude and engine speed. 1・
...Main engine, 5...Electronic governor, 7...Crankshaft, 8...Torsional amplitude measurement sensor (electromagnetic pickup)

Claims (1)

[Claims] A marine vessel characterized in that a crankshaft torsional vibration amplitude measurement sensor is attached to the front side of the engine, and this sensor is linked to an electronic governor so that when the torsional vibration exceeds a certain level, a command to increase or decrease fuel is given to the electronic governor. Automatic avoidance device for main engine torsional vibration dangerous rotation range.