JPH0986481A - Bottom structure of water jet propulsion boat - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve maneuverability and perform sufficient jump through simple constitution. SOLUTION: In the bottom structure of a water jet propulsion boat wherein a jet pusher is installed at a stern bottom, a first stepper 61 consisting of a surface higher than that of the front side is formed at the stern bottom and a second stepper 62 having width narrower and high higher than the width and the height of the first step 61 is formed on the rear side of the first stepper 61. The size of the step of the second stepper 62 is set to a value higher than that of the step of the first stepper 61, a speedometer 64 is attached to the first stepper, and a drain plug 63 is arranged at a second stepper front wall 620 between the first and second steppers 61 and 62.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ship bottom structure of a water jet propulsion watercraft such as a water jet propulsion watercraft.

[0002]

2. Description of the Related Art Recently, water jet propulsion boats, which are equipped with water jet propulsion machines and are capable of gliding over the sea at high speed to perform various operations such as sudden turns and sudden stops, have been widely used. And, in this ship, the operation of lifting the bow and jumping during high-speed gliding may be performed.

[0003]

In the hull of the above construction, since the bottom plate of the ship is formed by a continuous surface (curved surface in the width direction) from the bow to the stern end, the bow during the gliding When carrying out a jump by lifting the ship, it is necessary to deeply sink the stern bottom into the water, and there is a problem that it is difficult to sufficiently lift the bow and perform a sufficient jump due to the large resistance. Therefore, it is conceivable to provide a stepper at the bottom of the stern with a surface located above the front bottom of the stern. In order to perform a sufficient jump, it is desirable that the step between the stepper and the ship bottom in front of the stepper is large. Here, if the length of the stepper in the hull length direction is increased, the same effect as if the hull length became short occurs when the hull sways (pitches) in the forward-backward direction during navigation, resulting in pitching. Will become bigger. On the other hand, if the length of the stepper in the length direction of the hull is shortened, the stern side end of the bottom of the stepper in front of the stepper sinks deeply into the water when the bow is to be lifted.

The present invention has been made in order to eliminate the above-mentioned conventional drawbacks, and a water jet propulsion system in which a large bow is lifted to make a large jump and large pitching is less likely to occur It is intended to provide a boat bottom structure.

[0005]

According to a first aspect of the present invention, in a bottom structure of a water jet propulsion boat in which a jet propulsion device is installed on the stern bottom, the stern bottom is a surface located above the front bottom. And a second stepper having a surface located above the first stepper is formed at the stern end of the ship bottom on the rear side of the first stepper.

In the above construction, the first stepper and the second stepper make the bottom of the ship higher as it approaches the stern end, so that the second stepper is separated from the bottom of the front of the first stepper by a large amount. It will be. Also, the amount by which the first stepper separates above the ship's bottom in front of it is less than that by the second stepper, but when the bow is lifted, the amount by which the ship's bottom sinks into the water as it moves away from the stern end toward the front. Therefore, the first stepper is not so much submerged when the bow is greatly lifted, and the position of the first stepper is increased to the position of the second stepper, that is, from the front end of the first stepper to the first stepper. The same effect can be obtained as when the two steppers up to the rear end are formed on the same plane, which is largely separated upward from the ship bottom on the front side of the first stepper. Therefore, the bottom of the stern end of the first stepper and the second stepper does not sink deeply into the water when the bow is lifted during the sailing,
It is possible to lift the bow greatly and perform a sufficient jump.

Further, since the first stepper is located below the second stepper, when the hull sways in the front-rear direction during traveling, when the position of the first stepper is raised to the position of the second stepper. It is possible to prevent the rear end portion of the first stepper from being submerged in water at a time when the shaking is small as compared with the case of FIG.

According to a second aspect of the invention, the step size between the first stepper and the ship bottom in front of the first stepper is the same as that of the first stepper and the second stepper.
The size is set smaller than the step size between the stepper and the stepper.

With the above construction, when the hull sways in the front-back direction during sailing, the rear end of the first stepper is surely prevented from being submerged in the water at a time when the sway is smaller, and pitching becomes larger. To be done.

According to the third aspect of the present invention, a drain plug is provided on the front wall of the second stepper between the first stepper and the second stepper.

In the above structure, by installing the drain plug on the wall between the first stepper and the second stepper, the space can be effectively used.

According to a fourth aspect of the invention, the width of the second stepper is set smaller than the width of the first stepper.

With the above arrangement, it is possible to easily make a sharp turn by sliding the stern part sideways.

According to a fifth aspect of the present invention, the second stepper front wall between the first stepper and the second stepper and the first stepper are joined at a substantially right angle, and the second stepper and the stern plate are curved. It is joined through the surfaces.

In the above structure, the step size between the first stepper and the ship bottom on the front side thereof is set smaller than the step size between the first stepper and the second stepper, so that the front side of the first stepper is set. It is conceivable that the water cut at the trailing edge of the ship's bottom will splash upwards and hit the rear end of the first stepper, but the second stepper front wall and the first stepper between the first stepper and the second stepper Since and are joined substantially at right angles, the water splashed on the rear end of the first stepper is surely cut off at the rear edge of the first stepper. Therefore, the second stepper is largely separated from the first stepper, and the scattered water is prevented from hitting the second stepper, so that the jump can be performed smoothly. On the other hand, since the second stepper and the stern plate are joined to each other via the curved surface, even if the rear end of the second stepper should be submerged in water when the bow is lifted, this is a curved surface. Since it is formed, it does not get caught on the surface of the water and can be immersed in water smoothly. With such a configuration and operation, the jump can be smoothly performed.

[0016]

1 to 4, an operation handle 20 is installed on a hull centerline of a hull 1 of a small boat near the center of the hull 1, and a driver's seat seat extending in the stern direction on the rear side thereof. 2 and a rear seat seat 21 are provided, and a foot deck 30 on which people on the seat seats 2 and 21 can put their feet is formed on both sides thereof. A storage compartment 80 is arranged below the rear seat seat 21, the rear seat seat 21 functions as a lid of the storage compartment 80, and the upper opening of the storage compartment 80 can be opened by removing the rear seat seat 21. I am trying.

On the lower front side of the driver seat 2 is formed a fuel cock 73 and an air intake (through hole) 74 for taking air into the inside of the hull. The fuel cock 73 is operated by a driver straddling the seat 2, but since an air intake 74 is formed in the vicinity of the fuel cock 73, there is always an air flow in this portion. Therefore, even if water is applied to the fuel cock 73, the fuel cock 73 is easy to dry, which is advantageous in that it is easy to operate.

Inside the bow, as shown in FIG.
A bow deck 7 is formed, and the bow deck 7 has a V-shaped side surface so that the central portion in the lengthwise direction of the ship is higher.
And an air intake duct 72 is provided. The upper side of the bow deck 7 is covered with a bow deck cover 76 and a storage case cover 75. Since the bow deck 7 is formed in a V shape instead of being flat, the strength against a downward load is large and the area of the deck surface of the bow deck 7 is increased. There is also an advantage that the air intake duct 72 can be easily installed. Further, a planar U-shaped grip member 8 is attached so as to cover both sides and the rear base of the rear seat 21 and grips the rear end of the grip member 8 when an underwater person gets on the boat from the stern end. I am trying.

Inside the center of the hull, an engine 5 is installed near the center in the longitudinal direction on the center line of the hull, and a water jet propulsion unit 4 extending to the stern end is installed on the rear side thereof. The shaft of an impeller that rotates inside the machine 4 is connected to the drive shaft of the engine 5. The water jet propulsion unit 4 is arranged in a stern casing (stern pump chamber) 44 whose rear part opens at the stern end, and the rear part of the jet water jet propulsion unit 4 extends in the stern pump chamber 44 to the stern end and its rear end. A steering nozzle and a reverse bucket 41 are provided in the section. Further, the water jet propulsion device 4 is provided with a water inlet port 42 opening to the bottom of the ship, and water is introduced from this water inlet port 42 by rotation of the impeller,
The propulsive force and the turning force are generated in the hull by injecting water in a predetermined backward direction from the water injection port 41 at the stern.

Exhaust gas expansion chambers 51 of the engine are arranged on the upper part of one side of the engine 5, respectively, and the water jet propulsion unit 4 and the stern are provided at the tip of the first exhaust pipe (hose) 59 derived therefrom. The second exhaust pipe 53 is connected to a water lock 52 arranged on one side of the pump chamber 44, and the second exhaust pipe 53 from the water lock 52 extends upward on the center line of the hull and then bends to be oblique from above the stern pump chamber 44. It extends rearward and downward (formed in an inverted U shape), is connected to a wall 45 formed obliquely upward and forward at the upper front end of the stern pump chamber 44, and opens into the stern pump chamber 44. Since the wall 45 is formed obliquely upward and upward, it is not necessary to further bend the tip portion of the second exhaust pipe 53 formed in an inverted U shape at the portion connecting to the stern pump chamber 44, and the piping can be easily handled. Has become.

A stern pump chamber 44, in which the rear portion of the water jet propulsion device 4 is arranged, is formed at the center of the stern in the width direction of the stern. A stepper 61 is formed, and on the rear side of the first stepper 61, a second stepper 62 narrower in width and higher in height than the first stepper 61 is formed at the stern end, and the rear end of the second stepper 62 is formed. It is continuous with the stern plate (transom) 66 via a curved surface. The length A of the first stepper 61 in the hull length direction and the length B of the first stepper 61 in the hull length direction are substantially the same, and the step size of the second stepper 62 (of the second stepper 62 Height C of front wall 620)
Is larger than the step size of the first stepper (the height D of the front wall 610 of the first stepper 61). An impeller-type speed sensor 64 is attached to the rear end of the first stepper 61, and the front wall 62 of the second stepper 62 is attached.
A drain plug 63 is attached to 0. Further, both the first stepper 61 and the second stepper 62 are inclined so as to be positioned higher as they go outward in the ship width direction.

An aluminum alloy ship bottom plate 13 is mounted between the first steppers 61 on both sides to cover the water jet propulsion unit 4 housed in the pump chamber 44 from below. The bottom plate 13 has slopes 6 formed on both inner ends of the first stepper 61 on both sides thereof.
11, the bottom surface of which is formed as a horizontal plane connecting the ridgelines 612 on both sides to each other. Although the rear edge of the ship bottom plate 13 is aligned with the rear edge of the first stepper 61 in bottom view, it extends to the rear edge of the second stepper 62 to protect the rear portion of the water jet propulsion machine. You may do it.

A sponson 9 is attached to the stern side of the ship, and the sponson 9 is constructed as shown in FIGS. That is, the sponson 9 is composed of a main body 90 and a mounting member 91, and the mounting member 91 has a plurality of (two in this example) support pins 92 on a long and narrow plate member to be mounted on a side plate of a ship at predetermined intervals in the longitudinal direction of the hull. The sponson body 90 is formed into a semi-cylindrical shape which is elongated in the ship length direction and has a tapered bow on the bow side. The body 90 is provided with fitting holes 93 at positions corresponding to the support pins 92. Each has an adjusting nut 94
Is to be inserted. This adjustment nut 9
In No. 4, a flange 942 is formed on one end of a cylindrical body, and an operation projection 944 is formed on the end surface thereof, and an axial through hole 940 is eccentric from the axial center of the adjust nut 94. Is formed in position. The through hole 940 is formed to have a size such that the collar 941 is fitted to the support pin 92 in an externally fitted state. The adjusting nut 94 is fitted into the fitting hole 93 of the main body 90, and the flange 942 is fitted into the fitting hole. The washer 922 is brought into contact with the step portion 932 and the support pin 92 is passed through the through hole 940.
And the nut 921 to tighten the body 90
Is fixed to the mounting member 91.

When the adjusting nut 94 is fitted into the fitting hole 93 of the main body 90, when the adjusting nut 94 is rotated around the support pin 92 with respect to the fitting hole 93, it is formed eccentrically with respect to the support pin 92. The position of the adjusting nut 94 changes within the fitting hole 93.
By appropriately rotating the adjusting nut 94, the main body 90 moves in the vertical and front-back directions with respect to the support pin 92, and the main body 90 is attached to the attachment member 91 fixed to the side plate (attachment state (attachment). Position) can be changed.

When the adjusting nut 94 at one end (for example, the stern side end) is adjusted in this way to change the position of one end of the main body 90 with respect to the mounting member 91, the other fitting hole is formed. The position of the support pin 92 within 93 is also affected, so that the other adjustment nut 94
Also, it is necessary to adjust the position in the fitting hole 93 according to this change. In this embodiment, both adjusting nuts 94 having the same shape are used. However, for example, the adjusting nut at the end of the bow is not provided with the eccentric through hole 940, but is passed through the axial center of the main body 90. By forming an elongated through hole in the length direction and rotating the stern-side adjust nut 94, the stern-side end of the main body 90 is moved in the vertical and front-back directions, and the bow-side end is mainly in the front-back direction. You may make it adjust so that only it moves.

7 and 8 show another embodiment of the sponson, in which the mounting member 91 has the same construction as that described above, but the body 90 has one adjusting hole 95 and one through hole 96. Are formed. The adjustment hole 95 is elongated in the vertical direction, and is curved so as to draw an arc locus with the other through hole 96 as the center of curvature. In this configuration, in a state in which the support pin 92 on the bow side is passed through the through hole 96 via the collar 941, the support pin 92 on the stern side is changed in the up-down direction in the adjustment hole 95, The stern end of the main body 90 is oscillated and displaced in the up-down direction about the through hole 96 as a center for fastening and fixing. As described above, in this example, the position adjustment for vertically displacing the stern end of the main body 90 can be performed.

As described above, since the mounting position of the sponson 9 can be easily adjusted by adjusting the nut 921, the mounting position of the sponson 9 can be lowered, for example, in the case of a one-person boat, and also in the case of a three-person boat. When is Sponson 9
The mounting position of the sponson 9 can be set to the most preferable state in accordance with the number of passengers, for example, by increasing the mounting position of.

In the above structure, when the driver lifts the bow from the gliding state of the hull 1, only the stern comes into contact with the water surface 100, as shown in FIG. The stern also jumps away from the water surface 100. The ship bottom 11 does not extend to the stern end, and the first and second steppers 61 and 62 make the ship bottom higher in sequence, so
The stepper 62 is separated upward from the ship bottom on the front side of the first stepper 61. Also, the amount by which the first stepper separates above the ship's bottom in front of it is less than that by the second stepper, but when the bow is lifted, the amount by which the ship's bottom sinks into the water as it moves away from the stern end toward the front. It reduces the number of the
The stepper is not so submerged in water, and the same effect can be obtained as when the position of the first stepper is raised to the position of the second stepper. Therefore, when performing a jump by lifting the bow of the boat while sailing, the bottom of the stern end, which is composed of the first stepper and the second stepper, does not sink deeply into the water, and the bow is greatly lifted for a sufficient jump. Can be done.

Further, since the first stepper is located below the second stepper, if the hull sways in the front-rear direction during traveling, if the position of the first stepper is raised to the position of the second stepper. It is possible to prevent the rear end portion of the first stepper from being submerged in water at a time when the shaking is small as compared with the case of FIG.

Further, when the hull sways in the front-rear direction during traveling, it is reliably prevented that the rear end portion of the first stepper is submerged in water and the pitching becomes large when the swaying is smaller. . Further, by installing the drain plug on the wall between the first stepper and the second stepper, it is possible to effectively utilize the space. Further, by setting the width of the second stepper to be smaller than the width of the first stepper, it is possible to easily slip the stern and make a sharp turn.

Further, since the step size between the first stepper and the ship bottom on the front side thereof is set smaller than the step size between the first stepper and the second stepper, the ship bottom on the front side of the first stepper is set. It is conceivable that the water cut at the rear edge will splash upward and hit the rear end of the first stepper, but the second stepper front wall and the first stepper between the first stepper and the second stepper will be separated. Since they are joined at almost right angles, the first
The water scattered at the rear end of the stepper is reliably cut off at the rear edge of the first stepper. Therefore, in combination with the second stepper being largely separated upward from the first stepper, the scattered water is prevented from hitting the second stepper,
The jump is performed smoothly. On the other hand, since the second stepper and the stern plate are joined to each other via the curved surface, even if the rear end of the second stepper should be submerged in water when the bow is lifted, this is a curved surface. Because it is formed
It does not get caught on the surface of the water and can be immersed in water smoothly. As a result, the jump can be performed smoothly.

It should be noted that when the hull 1 is overturned, the second exhaust pipe 53
Water enters from the top of the second exhaust pipe 53 from the inverted U-shaped top part due to the restoration of the hull 1, and part of the water enters the water lock 52, and the rest is discharged into the stern casing 44 again. Further, the water that has entered the water lock 52 collects inside and is prevented from entering the engine 5. Moreover, since the second exhaust pipe 53 is formed in an inverted U shape, the effect of preventing water from entering is achieved also in this portion.

[0033]

According to the first aspect of the present invention, the first stepper and the second stepper make the bottom of the ship gradually higher as it approaches the stern end, so that the second stepper is higher than the bottom of the front of the first stepper. Will also be separated by a large amount. Further, although the amount by which the first stepper is separated upward from the ship bottom on the front side thereof is smaller than that by the second stepper,
When the bow is lifted, the amount of the bottom of the ship sinking into the unwater decreases as it moves further away from the stern end. Therefore, the first stepper does not sink much in the water when the bow is lifted greatly. , The position of the first stepper is raised to the position of the second stepper, that is, the front end of the first stepper to the rear end of the second stepper is formed on the same plane, which is largely separated upward from the bottom of the ship on the front side of the first stepper. The same effect as can be obtained. Therefore, when performing a jump by lifting the bow of the ship during the cruise, the bottom of the stern end consisting of the first stepper and the second stepper does not sink deep into the water, and the bow of the bow is greatly lifted for a sufficient jump. Can be done.

Further, since the first stepper is located below the second stepper, if the hull sways in the front-rear direction during traveling, if the position of the first stepper is raised to the position of the second stepper. It is possible to prevent the rear end portion of the first stepper from being submerged in water at a time when the shaking is small as compared with the case of FIG.

According to the second aspect of the present invention, when the hull sways in the front-rear direction during traveling, the rear end of the first stepper may be submerged in water at a time when the sway is smaller, resulting in greater pitching. Certainly prevented.

According to the invention of claim 3, the first stepper and the second stepper are provided.
By installing the drain plug on the wall between the stepper and the stepper, the space can be effectively used.

According to the fourth aspect of the invention, it is possible to easily make a sharp turn by sliding the stern part sideways.

According to the fifth aspect of the present invention, the step size between the first stepper and the ship bottom in front of the first stepper is set smaller than the step size between the first stepper and the second stepper. It is conceivable that the water cut at the rear edge of the ship bottom on the front side of the stepper will splash upwards and hit the rear end of the first stepper, but with the second stepper front wall between the first stepper and the second stepper. Since the first stepper and the first stepper are joined at substantially right angles, the water splashed on the rear end of the first stepper can be reliably cut off at the rear end edge of the first stepper. Therefore, the second stepper is largely separated from the first stepper, and the scattered water is prevented from hitting the second stepper, so that the jump can be performed smoothly. Meanwhile, the second
Since the stepper and the stern plate were joined via the curved surface,
Even if the rear end of the second stepper should be immersed in the water when the bow is lifted, it is formed into a curved surface, so it does not get caught on the surface of the water, so it can be immersed in the water smoothly. can do. As a result, the jump can be performed smoothly.

[Brief description of drawings]

FIG. 1 is a bottom perspective view of a hull showing an embodiment of the present invention.

FIG. 2 is a plan view of FIG.

FIG. 3 is a side view of FIG. 2;

FIG. 4 is a vertical cross-sectional view at the drain plug mounting position on the bottom of the stern.

FIG. 5 is an exploded perspective view showing an example of a sponson.

FIG. 6 is a cross-sectional view of FIG.

FIG. 7 is an exploded perspective view showing another example of a sponson.

8 is a cross-sectional view of FIG.

[Explanation of symbols]

 1 Hull 2 Seat Seat 4 Water Jet Propulsion Machine 5 Engine 11 Bottom Plate 21 Rear Seat Seat 44 Stern Casing (Pump Room) 61 First Stepper 62 Second Stepper

Claims (5)

[Claims] 1. In a ship bottom structure of a water jet propulsion boat in which a jet propulsion machine is installed on the stern bottom, a first stepper is formed on the stern bottom, the first stepper having a surface located above the front bottom. A bottom structure of a water jet propulsion boat, characterized in that a second stepper having a surface located above the first stepper is formed at the stern end of the bottom of the rear of the one stepper. 2. The step size between the first stepper and the ship bottom in front of the first stepper is set smaller than the step size between the first stepper and the second stepper. The bottom structure of the water jet propulsion watercraft described in 1. 3. The ship bottom structure for a water jet propulsion watercraft according to claim 2, wherein a drain plug is provided on a front wall of the second stepper between the first stepper and the second stepper. 4. The bottom structure of a water jet propulsion boat according to claim 1, wherein the width of the second stepper is set smaller than the width of the first stepper. 5. The second stepper front wall between the first stepper and the second stepper and the first stepper are joined at a substantially right angle, and the second stepper and the stern plate are joined via a curved surface. The bottom structure for a water jet propulsion watercraft according to claim 2, wherein