JPH075120B2 - Propulsion power unit for ships - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a marine propulsion power unit using an internal combustion engine, which is used, for example, in a main sail slave ship.

(Prior Art) A marine propulsion power plant using an internal combustion engine is adjusted so that a fuel consumption rate is minimized in a high load region where a required output is high. Therefore, even if the required output is low, it is necessary to always operate at high load to reduce the fuel consumption rate.

Therefore, as a means for constantly operating with a high load, conventionally, a cylinder number control engine that changes the number of ignition cylinders according to a required output, and a plurality of internal combustion engines are connected to a gear box 11 that interlocks with a propulsion shaft via a clutch 3, and a request is made. There is a multi-engine, one-propulsion shaft system (see FIG. 5) in which only the necessary engine is operated according to the output and other engines are stopped.

(Problems to be solved by the invention) However, in the above-mentioned means, since the piston in the idle cylinder is also moved in conjunction with the piston in the ignition cylinder, friction loss between the piston ring and the cylinder liner in the idle cylinder part, In addition, mechanical loss such as intake / exhaust loss (especially in the case of a 4-stroke engine) is large, which prevents a decrease in fuel consumption rate (see FIG. 4). In addition, since the clutch 3 can disconnect each internal combustion engine from the gear box 11, it is possible to completely stop the idle engine, but it is necessary to provide gear boxes in addition to the clutches for the number of internal combustion engines. There is a drawback that equipment costs increase. Furthermore, since each gear in the gear box is constantly rotating, these mechanical losses cannot be ignored.

The present invention was devised to solve the above-mentioned conventional problems, and it is possible to reduce the fuel consumption rate according to the required output by eliminating the mechanical loss of the idle engine, and to reduce the cost such as equipment cost. It is an object of the present invention to provide a propulsion power unit for ships that can achieve the above.

(Means for Solving Problems) In a marine vessel propulsion power unit of the present invention, a plurality of internal combustion engines are arranged in series, and the crankshafts of the internal combustion engines are connected via a clutch, and the internal combustion engines are also connected. A speed governor is attached to the crank, and the crank position and rotation speed of each crankshaft located before and after the clutch are detected, and one of the speed governors is controlled based on the crank position and the rotation speed. By providing the clutch control device for connecting the clutch to the clutch when the crank position and the rotation speed of the shaft are in an appropriate synchronous state (a crank arrangement state with little vibration and a state where the rotation speed is substantially the same), the clutch control device is provided. It achieves the purpose.

(Embodiment) FIG. 1 shows an embodiment of the present invention. Reference numerals 1 and 2 are an internal combustion engine, 3 is a clutch, 4 is a clutch control device, and 7 is a speed governor.

The rear end of the crankshaft 6 of the internal combustion engine 1 is connected via a flywheel 8 to a propulsion shaft 5 that drives a screw propeller. Another internal combustion engine 2 is arranged in series on the front side of the internal combustion engine 1, and a crankshaft 6 of a rear internal combustion engine (hereinafter, rear engine) 1 and a front internal combustion engine (hereinafter, front engine) 2 The crankshaft 6 ′ is connected via the clutch 3. Each internal combustion engine 1 and 2 is equipped with a speed governor 7 for adjusting its rotation speed, and each flywheel.
A turning gear 9 capable of meshing with the flywheel 8 and a turning device 10 for driving the turning gear 9 are mounted near 8, 8 respectively. Further, a clutch control device 4 is attached to the clutch 3. The clutch control device 4 detects the crank position and rotational speed of the crankshafts 6, 6'of the rear engine 1 and the front engine 2, and controls the governor 7 of the front engine 2 if there is a difference in rotational speed. The clutch 3 is connected when the crank position and the rotation speed are synchronized.

Hereinafter, the operation of the present invention will be described in this embodiment.

When the required output is high, the clutch 3 is connected to operate both internal combustion engines 1 and 2 at the same rotation speed. When the required output is low, the clutch 3 is shut off to stop the front engine 2 and only the rear engine 1 is operated under high load. The relationship between the engine speed and the output is shown in the graph of FIG. 2 when taking the characteristic of a ship using a variable pitch propeller as an example.

When the required output changes from high to low, the clutch 3 is shut off and then the front engine 2 is stopped. On the contrary, when the required output changes from the lower side to the higher side, the front side engine 2 is started, the rotational speed of the operating rear side engine 1 is increased, and the front side engine 2 and the rear side engine 1 rotate. The clutch 3 is connected by synchronizing the speed and the crank position.

In the case of a small-cylinder engine (for example, 3 cylinders or less) that is started by starting air, starting air is often difficult because the starting air input period does not overlap with other cylinders. In such a case, the following activation method can be considered.

1) When the whole engine is stopped Turn the crankshaft 6 (6 ') to the optimum crank position by the turning device 10 to connect the clutch 3 and start it by increasing the number of start-up air injection cylinders and make a certain rotation. When reaching the speed, shut off clutch 3. When the required output is high,
"When the required output changes from low to high" above
Connect Clutch 3 in the same manner as in. When the required output is low, the front engine 2 is stopped as it is.

2) When the rear engine is in operation and the required output increases, connect the clutch 3 at an arbitrary crank position to make the front engine 2
When the crankshaft 6'of the crankshaft reaches a certain rotational speed, the clutch 3 is shut off, fuel is injected into the front engine 2, and the clutch is operated by the same procedure as the "when the required output changes from the lower side to the higher side". Connect 3

Note that FIG. 3 is a graph showing the relationship between the required output and the fuel consumption rate in the present invention. Comparing this graph with the conventional one (FIG. 4), it can be seen that the present invention can achieve a significant fuel consumption reduction effect.

Further, the present invention can be applied not only to ships but also to internal combustion engines for vehicles.

(Effect of the invention) Since there is no mechanical loss of the stopped engine, the fuel consumption rate is small when the required output is low compared to the conventional cylinder number control engine,
Highly effective in reducing fuel consumption.

The number of clutches is smaller than that of the conventional multi-engine, single-propulsion shaft system, and no gear box is required. Therefore, cost reduction, easy maintenance, and weight reduction of the power unit can be achieved.

The clutch control device can automatically connect the stopped internal combustion engine to the operating internal combustion engine in a synchronized state in which each crank position and rotation speed are optimal. Further, the clutch control device can reliably and easily start the air when the whole engine is stopped and the front engine when the rear engine is operating.

[Brief description of drawings]

FIG. 1 is a plan view showing an embodiment of the present invention, FIG. 2 is a graph showing a relationship between engine speed and output in the present invention, and FIG. 3 is a graph showing a relationship between output and fuel consumption rate in the present invention. FIG. 4 is a graph showing the relationship between output and fuel consumption rate in a conventional cylinder number control engine, and FIG. 5 is a conceptual diagram of a conventional multi-engine / propulsion shaft system. 1,2 Internal combustion engine, 3 clutch, 4 clutch control device, 5 propulsion shaft, 6,6 '... crankshaft, 7 speed governor, 8 flywheel, 9 ... … Turning gear, 10 …… Turning device, 11 …… Gear box.

Claims (1)

[Claims] 1. A plurality of internal combustion engines are arranged in series, the crankshafts of each internal combustion engine are connected via a clutch, and a speed governor is attached to each internal combustion engine, and they are positioned before and after the clutch. The crank position and rotation speed of each crankshaft are detected, and one of the speed governors is controlled based on this crank position and rotation speed, and the crank position and rotation speed of each crankshaft are brought into an appropriate synchronized state. A marine vessel propulsion power plant characterized in that a clutch control device for connecting the clutch is provided on the clutch.