JPS61287897A - Engine exhaust structure of small size boat - Google Patents

Abstract

PURPOSE:To aim at preventing water from entering into an engine upon turn- over of a small size boat, by downward opening an exhaust pipe connected to the engine, in an expansion chamber, and by positioning one end of a second exhaust pipe opened at the other end, outside of the boat, above the water surface upon turn-over of the boat. CONSTITUTION:The front end section of first exhaust pipe 36 connected to an engine is inserted into an expansion chamber 70, piercing through a surrounding wall 71 and the front end 37 of the section is extended and opened downward. Further in the expansion chamber 70, one end section of a second exhaust pipe 7 is extended and opened downward while the other end section 79 is opened outboard. Upon turn-over of the boat, although the opening end section 79 is positioned below the water surface so that water enters thereinto, water is prevented from entering into the expansion chamber 70 since the other end section of the pipe 7 is positioned above the water line 19. With this arrangement, it is possible to facilitate the manufacture thereof and to completely prevent water from entering into the engine.

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention relates to an exhaust structure for a small boat engine that can reliably prevent water from entering the engine when the boat capsizes. .

(Prior Art) Recently, water play equipment, which is a small boat with an engine and slides on water, has come into wide use. This ship often capsizes due to various movements such as sharp turns, so it is necessary to have a structure that prevents water from entering the engine when it capsizes. Conventionally, various structures for this purpose have been proposed. For example, a part with a pair of pipes attached to a sealed box is placed in the engine room, one pipe is connected to the engine, and the other pipe is connected to the engine. An exhaust structure has been adopted that directs the exhaust outside the hull. With this structure, it takes a lot of work to install the parts inside the engine room and lead the exhaust pipe out of the hull.
Furthermore, since the parts (exhaust structure) are placed inside the engine room, it is not possible to detect engine abnormalities from the exhaust structure.

(Purpose of the Invention) This invention was made in order to eliminate such conventional drawbacks, and is a simple structure that makes it possible to easily detect abnormalities in the engine. The present invention provides an exhaust structure for an engine of a small boat that can reliably perform the function of preventing water from entering the vessel.

(Structure of the Invention) The present invention provides a small boat in which a cockpit is formed at the rear of the hull and a seat is formed at the center in the width direction of the boat, and the lower side of the rear end of the seat is sealed. An expansion chamber is formed, in which one end of a first exhaust pipe connected to the engine extends downward and opens, and in the expansion chamber, one end of a second exhaust pipe opens outboard. The opening of the second exhaust pipe in the expansion chamber is set to be located above the water surface when the ship capsizes.

By forming the expansion chamber integrally with the hull under the rear seat, the exhaust structure can be easily configured, and engine abnormalities can be easily detected. It is.

(Example) In Figures 1 to 3, the upper deck 2 is
1 are joined together at their peripheral edges, and the stern plate 8 is joined together to form the hull 1, and the engine room 2 is sealed in a portion surrounded by the bulkhead 22, the bottom plate 2, and the upper deck 21.
0 is formed.

Further, a seat 5 is formed above the rear portion thereof, and a cockpit 50 is formed on both sides thereof.

A strut 60 is formed to protrude from the upper deck 21, and a handle 6 is formed at the upper end of the strut 60, so that the person 10 on the seat 5 can put his or her feet on the cockpit 50 and grip the handle 6 to drive the boat. I have to.

An engine 3 is disposed in the engine room 20, and a propeller shaft 30 rotated by the engine 3 has a watertight structure and passes through the bulkhead 22, and a propeller 31 attached to the tip thereof is configured to rotate in the waterway 32. has been done. A nozzle 35 is provided at the tip of the water channel 32 so that the direction can be changed.
is attached, and the water sucked in from the suction port 33 by the rotation of the propeller 31 is jetted in a predetermined direction from the nozzle 35, thereby turning and propelling the ship.

Further, an opening 23 is formed in the upper deck 21, and a surrounding wall 90 is provided inside the opening 23, so that the engine room 20 can be closed.
A ventilation chamber is formed within this surrounding wall 90, and the upper end of a ventilation pipe 91 opening into the engine room 20 is opened to ventilate the engine room 20. . Further, a fuel tank 4 is installed in the engine room 20, and an air intake pipe 94 connected to the fuel tank 4 opens into the ventilation room.

4 and 5, an expansion chamber 70 consisting of a closed chamber surrounded by a riser 55, a surrounding wall 71, and a stern plate 8 is formed at the rear lower side of the seat 5. Further, a first exhaust pipe 36 is connected to the engine 3 , and the tip end thereof penetrates the surrounding wall 71 and is inserted into the expansion chamber 70 .
7 extends downward and opens into room 70 in 1111.

Further, one end of the second exhaust pipe 7 extends downward and opens into the ventilation chamber 70, and the other end penetrates the wall of the recess 77 and opens outboard within the recess 77. In this way, the recess 7
The reason why the exhaust pipe 7 is opened therein is to prevent the opening 79 of the second exhaust pipe 7) from protruding outward from the stern plate 8. The distal end 37 of the first exhaust pipe 36 and the distal end of the second exhaust pipe 7 are set in the expansion chamber 70 at a higher position than the water 119 when the ship capsizes.

In the above configuration, under normal running conditions of the ship, engine 3
The exhaust gas is discharged overboard from the opening 79 through the first exhaust pipe 36, the tip 37, the expansion chamber 70 and the second exhaust pipe 7. At this time, if an abnormality occurs in the engine 3 (for example, when the cooling water of the engine 3 is cut off), the expansion chamber 70 will be heated abnormally, and the person 10 sitting on the expansion chamber 70 will not be able to easily notice the abnormality. can. ' If the boat capsizes while traveling, water will enter the second exhaust pipe γ because the opening 79 is located below the water line 19 as shown in FIG. Since the tip of the tube 7 is set at a position higher than the water line 19, water does not enter into the expansion chamber 70. Furthermore, since the tip 37 of the first exhaust pipe 36 is also set at a higher position than the water line 19,
Even if water enters the expansion chamber 70, water is prevented from entering the engine 3.

When the boat is raised from the above-mentioned capsized state, the water in the exhaust pipe 7 is dropped into the expansion chamber 70, but as a result, the water 78 stored in the expansion chamber 70 is discharged from the first exhaust pipe 36 and moved into the expansion chamber 70. As shown in FIG. 4, only the water up to the water level lower than the tip of the second exhaust pipe 7 is left behind. This remaining water 78 only accumulates in the upper part of the expansion chamber 70 (bottom in FIG. 5) when the ship capsizes and does not enter the second exhaust pipe 36.

In this way, water is reliably prevented from entering the engine 3 even when the boat capsizes or when the boat is raised from a capsized state. In addition, in the above configuration, the expansion chamber is configured at the stern, and the second
Since the exhaust pipe opens directly to the outside of the ship, it is not necessary to lead the exhaust pipe to the outside by passing through the hull skin, and therefore the exhaust structure is easy to manufacture.

(Effects of the Invention) As explained above, in this invention, the engine exhaust structure is provided under the seat and integrated with the hull, and with a simple structure, engine abnormalities can be easily detected. It is possible to reliably prevent flooding in the event of capsizing.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal cross-sectional view of a hull showing an embodiment of the present invention;
3 is a rear view thereof, FIG. 4 is a vertical sectional view of the ventilation section, and FIG. 5 is a view corresponding to FIG. 4 in an overturned state. DESCRIPTION OF SYMBOLS 1... Hull, 3... Engine, 20... Engine room, 7... Second exhaust pipe, 36... First exhaust pipe, 37... Tip part, 70... expansion chamber.

Claims (1)

[Claims] 1. A cockpit is formed at the rear of the hull, and
In a small boat having a seat formed at the center in the width direction, a sealed expansion chamber is formed below the rear end of the seat, and this expansion chamber has a first exhaust gas connected to the engine. One end of the second exhaust pipe extends downward and opens to the outside of the vessel, and one end of the second exhaust pipe extends downward and opens to the outside of the vessel, and the second exhaust pipe opens in the expansion chamber. An exhaust structure for an engine of a small boat, characterized in that the part is set to be located above the water surface when the boat capsizes.