JPH0634233Y2 - Fluid discharge device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a fluid discharge device for discharging seawater, engine oil leakage, etc. in a high-speed boat to the outside of the ship.

(Prior Art) In a small planing boat, invading seawater accumulates on the bottom of the ship and becomes sewage along with engine oil leakage. Conventionally, a drain pump driven by an electric motor has been used as a means for discharging this, but a pump using this pump is heavy and takes up space, and requires a storage battery as a power source. There are challenges.

In view of this point, as an example of the one configured to use the flow velocity of water during propulsion for draining,
There is a drainage device as disclosed in Japanese Utility Model Publication No. 53-159095. This drainage device forms a fluid discharge port at the bottom of the ship, and at the bottom of the ship, a bowl-shaped suction lid is arranged to cover the fluid discharge port, and the rear of the suction lid is opened toward the stern, and A drainage pipe is provided, one end of the drainage pipe is opened to the fluid discharge port, and the other end is opened to the vicinity of the bottom of the ship. A negative pressure is generated inside the suction lid as the boat propels. The bilge water is discharged from the drain pipe to the outside of the ship by pressure.

Further, in this type of watercraft, it is necessary to prevent the outboard fluid from flowing backward through the drainage pipe when the boat is stopped, and as described in JP-A-62-231890, it is considered in view of this point. In addition, it is also known that the drainage pipe is bent in an inverted U shape and a small hole is formed at the upper end thereof.

(Problems to be solved by the invention) However, even in the case where the negative pressure is generated as the boat is propelled and the negative pressure is used to discharge the bilge water, etc., it is accumulated in the boat. When the amount of fluid is large, it takes a long time to drain all the fluid. One of the causes is that, near the rear end of the fluid passage, air is entrained in the fluid passage due to the influence of waves or the like, and a boundary surface A is formed between the air and the fluid flowing along the ship bottom. (See the chain line in FIG. 1) and the negative pressure is reduced by the boundary surface A.

The present invention has been made in view of this point, and while preventing the reverse flow of the fluid in the drain pipe while the ship is stopped,
It is intended to provide a configuration that can realize a higher drainage efficiency than ever before at the time of propulsion.

(Means for Solving the Problems) In order to achieve the above-mentioned object, the means taken by the present invention are
A drainage pipe for discharging fluid such as bilge water is arranged inside a high-speed boat, and an opening is formed in an outer plate of the high-speed boat, and a fluid passage communicating with the opening and extending rearward is guided. One end of an inverted U-shaped drainage pipe, which is formed of a plate and has a small hole provided at a position higher than the drainage line, is connected to the opening. Also, an external fluid introducing means for introducing the fluid outside the high speed boat into the fluid passage is provided.

(Operation) During propulsion of a high-speed boat, a negative pressure is generated in the fluid passage communicating with the opening due to the flow velocity outside the outer plate, and this negative pressure discharges the bilge water and the like from the reverse U-shaped drain pipe. Will be. At this time, air is entrained in the fluid passage near the rear end of the fluid passage due to the influence of waves or the like, and a boundary surface A is formed between the air and the fluid flowing along the ship bottom.
Is formed (see the chain line in FIG. 1), and the negative pressure may decrease due to the boundary surface A. In the present invention, the external fluid introducing means guides the fluid outside the high-speed boat to the fluid passage. The inside of the fluid passage is disturbed to prevent the occurrence of the boundary surface.

Further, in a state where the negative pressure is not generated, such as when the ship is stopped, air is supplied from the small holes formed in the drainage pipe to prevent backflow of water from the outside of the ship.

(Embodiment) Next, the present invention will be described with reference to an embodiment. FIG. 1 is a longitudinal sectional view of a ship bottom portion. An opening 2 is formed in the ship bottom 1, and one end of a drainage pipe 3 is formed in the opening 2. The drainage pipe 3 is connected to the inside of the ship and is guided in an inverted U-shape inside the ship, and the other end is close to the ship bottom. The disposed drain pipe 3
Has passed through at least a height higher than the water line 7, and a small hole 5 is provided at a height higher than the water line. A guide plate 4 is attached to the lower side of the opening 2 and the rear of the guide plate 4 is opened to form a fluid passage. The arrow indicates the bow direction.

Another feature of the present invention is that the guide plate 4 is provided with injector small holes 6 as external fluid introducing means to disturb the negative pressure region in the fluid passage. That is, when the boat is propelled, the external fluid introduced from the injector small holes 6 disturbs the inside of the fluid passage to prevent the formation of the boundary surface of the gas-liquid layer and suppress the decrease of the fluid suction force. That is, near the rear end of the fluid passage, air is entrained in the fluid passage due to the influence of waves and the like, and a boundary surface A is formed between the air and the fluid flowing along the ship bottom (see the chain line in FIG. 1). ), The negative pressure may decrease due to the boundary surface A. However, in the configuration of the present example, the fluid outside the high speed boat is guided to the fluid passage by the injector small hole 6 to disturb the inside of the fluid passage to disturb the boundary. The surface is prevented from being generated, and the decrease in the fluid suction force is suppressed.

Hereinafter, the results of an experiment conducted to confirm the effect of this example will be described. The inventor of the present application conducted an experiment on a ship bottom 1 having a thickness of 34 mm and a drainage pipe 3 having a diameter of 16 mmφ.
At ~ 50km / h, a negative pressure of about 100mmHg was obtained, and a bilge water suction rate of 40l / min or more was obtained.

The bilge water accumulated at the bottom of the ship is thus opening 2
It is effectively discharged by the negative pressure generated at. The small hole 5 at this time is 0.7 mmφ. It was also found that if the small holes 5 are too large, the suction force is lost and the bilge water cannot be discharged. FIG. 2 is a diagram showing the relationship between negative pressure and ship speed.

Further, as an experiment for confirming the effect of the injector small hole 6, the discharge amount of the bilge water was measured for each of the type I without the injector small hole 6 and the type II with the injector small hole 6 like this example. Compared. The results are shown in FIG. Thus, in the case where the injector small hole 6 is not provided, the suction amount of bilge water is 30 l / h at a ship speed of 50 km / h.
While it is about min, the one with injector small holes 6 has a bilge water discharge rate of 46 to 52 l / at a ship speed of 50 km / h.
You can get min.

(Effect of the Invention) As described above, the present invention forms the opening in the outer plate of the high-speed boat,
A fluid passage communicating with the opening and extending rearward is formed by a guide plate, and one end of an inverted U-shaped pipe provided with a small hole at a position higher than the dwarf line is connected to the opening, and Since the external fluid introducing means for introducing the fluid outside the high-speed boat into the fluid passage is provided, the fluid such as the bilge water at the bottom of the vessel is sucked very efficiently during propulsion, and the bottom opening is opened when the vessel is stopped. Water does not flow back through the pipe without plugging the part or installing a check valve in the middle of the pipe, so preventing backflow of fluid in the drainage pipe while stopped During propulsion, it is possible to achieve unprecedented high drainage efficiency.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a vertical sectional view of a ship bottom portion for explaining the present invention.
FIG. 2 is a diagram showing the relationship between negative pressure and ship speed, and FIG. 3 is a diagram showing the results of experiments conducted to confirm the effect of the injector small holes. 1 ... ship bottom, 2 ... opening, 3 ... drainage pipe, 4 ...
Guide plate, 5 ... small hole, 6 ... injector small hole (external fluid introducing means).

Claims (1)

[Scope of utility model registration request] 1. A high-speed boat, wherein a drainage pipe for discharging a fluid such as bilge water is provided inside a high-speed boat, and an opening is formed in an outer plate of the high-speed boat, which communicates with the opening. A fluid passage extending rearward and rearward is formed by a guide plate, and one end of an inverted U-shaped drainage pipe having a small hole provided at a position higher than the drainage line is connected to the opening, while a high speed boat is provided. A fluid discharge device comprising external fluid introducing means for introducing an external fluid into the fluid passage.