JPH04356293A - Structure of portion where water jet propulsion boat is fitted into ship to be propelled - Google Patents

Abstract

PURPOSE:To keep the propulsion performance of a water jet propulsion boat by fitting the bow of the water jet propulsion boat into a fitting recessed portion formed in a ship to be propelled so as to move the ship to be propelled using the water jet propulsion boat and, even if an eddy generates from the rear end edge of a bottom plate at the fitting recessed portion, preventing the eddy from entering a water inlet. CONSTITUTION:When the bow 24 of a water jet propulsion boat 1 is fitted into a fitting recessed portion 23 formed in a ship 18 to be propelled in order to move the ship 18 to be propelled using the water jet propulsion boat 1, the rear end edge 31 of the bottom plate 22 of the ship 18 to be propelled which corresponds to the water inlet 10 of the water jet propulsion boat 1 is separated foward from the water inlet 10.

Description

[Detailed description of the invention]

0001

[Industrial Field of Application] This invention relates to the connection between a water jet propulsion boat and a propelled boat that is moved to a desired position by the water jet propulsion boat and used as a floating base for the same water jet propulsion boat. Regarding joint structure.

0002

2. Description of the Related Art Conventionally, water jet propulsion boats used mainly for leisure purposes have been constructed as follows. That is, the hull is provided with a duct extending in the front-rear direction, the front end of this duct opens midway between the front and rear of the ship's bottom, serving as a water intake, and the rear end opens at the stern, serving as a water spout. A propulsion propeller is also provided within this duct. By driving the propulsion propeller, water is sucked into the duct through the water intake port, and this water is injected from the water spout to the rear of the hull, thereby propelling the water jet propulsion boat. It has become.

On the other hand, when using the above-mentioned water jet propulsion boat, a propelled boat serving as a floating base for taking off and taking off the boat may also be used. In this case, the water jet propulsion boat is used to move the propelled vessel to a desired position, such as offshore. To explain this more specifically, a fitting recess into which the water jet propulsion boat is removably inserted is formed at the stern of the propelled boat. If the water jet propulsion boat is propelled with the water jet propulsion boat fitted into this fitting recess, the propelled boat can be moved to a desired position.

0004

[Problem to be Solved by the Invention] By the way, when a propelled boat is moved by a water jet propulsion boat, a large number of vortices are generated one after another in the water from the rear edge of the bottom plate of the fitting recess toward the rear. There is. Conventionally, this vortex has not been taken into account, and therefore, this vortex enters the duct through the water intake, which reduces the performance of the propulsion propeller and reduces the ability of water jet propulsion boats. There was an inconvenience in that it hindered progress.

[0005]

[Purpose of the Invention] This invention was made in view of the above-mentioned circumstances, and when the propelled vessel is moved by a water jet propulsion boat, the rear of the bottom plate of the fitting recess formed in the propelled vessel is To maintain good propulsion performance by a water jet propulsion boat by preventing the vortex from entering a water intake port even if a vortex is generated from the edge.

[0006]

[Means for Solving the Problems] A feature of the present invention for achieving the above object is that water is sucked in from a water intake port formed in the front and rear part of the bottom of the ship, and this water is injected toward the rear of the ship. In a structure of a fitting part between a water jet propulsion boat and a propelled boat, the bow of the water jet propulsion boat that moves forward and a fitting recess formed in the propelled boat are removably fitted, When the bow of the water jet propulsion boat is fitted into the fitting recess of the propelled vessel, the rear edge of the bottom plate of the fitting recess corresponding to the water intake port is positioned forward of the water intake port. This is where I decided to leave. In addition, instead of separating the rear edge of the bottom plate of the fitting recess corresponding to the water intake port further forward than the water intake port as described above, the water intake port is placed in the bottom plate of the fitting recess. A communication port communicating downward may be formed in the upper bottom plate, and the front edge of the opening edge of the communication port may be spaced further forward than the water intake port.

[0007]

[Operation] The operation of the above configuration is as follows. When the water jet propulsion boat 1 is fitted into the fitting recess 23 formed in the propelled boat 18 in order to move the propelled boat 18 by the water jet propulsion boat 1, the water intake of the water jet propulsion boat 1 is A rear edge 31 of the reinforcing plate (bottom plate) 22 of the propelled vessel 18 corresponding to the inlet 10 is spaced further forward than the water intake 10 . Therefore, when the propelled vessel 18 is moved by the water jet propulsion boat 1, even if a large number of vortices 33 are generated one after another in the water 32 from the rear edge 31 of the reinforcing plate (bottom plate) 22 toward the rear, By the time these vortexes 33 reach the water intake port 10, they are diffused, weakened, and disappear, thereby preventing these vortices 33 from entering the water intake port 10.

Note that instead of separating the rear edge 31 of the reinforcing plate (bottom plate) 22 of the propelled ship 18 corresponding to the water intake port 10 forward of the water intake port 10 as described above, A communication port 59 that communicates the intake port 10 with the lower part of the reinforcing plate (bottom plate) 22 is formed in the reinforcing plate (bottom plate) 22, and the front edge 60 of the opening edge of the communication port 59 is located in front of the water intake port 10. It may be possible to separate the In this way, when moving the propelled vessel 18 by the water jet propulsion boat 1, even if a large number of vortices 33 are generated one after another in the water 32 from the front edge 60 of the communication port 59 toward the rear, these vortices By the time the vortices 33 reach the water intake port 10, they are diffused or weakened and disappear.
0 is prevented.

[0009]

Embodiments Hereinafter, embodiments of the present invention will be explained with reference to the drawings. (First Embodiment) FIGS. 1 to 4 show a first embodiment.

1 to 3, reference numeral 1 indicates a water jet propulsion boat, and an arrow Fr in the figure indicates the forward direction of the water jet propulsion boat 1 in the propulsion direction. The water jet propulsion boat 1 has a resin hull 2. A handle support part 3 is protruded from the top surface of the hull 2 at a midway point in the front and back, and a bar handle 4 is mounted on the handle support part 3 so that the bar handle 4 can be freely steered. is supported by. A seat 5 is provided on the rear portion of the hull 2, and footrest surfaces 6, 6 are formed on the left and right sides of the seat 5. The occupant is able to steer the bar handle 4 while straddling the seat 5 and placing his or her feet on the footrest surface 6.

A duct 8 having a circular cross section and extending in the longitudinal direction is provided at the rear of the hull 2, and this duct 8 is bent in a substantially V-shape when viewed from the side, and its front end is located at the midway between the front and back of the bottom 9 of the hull 2. This opening is the water intake port 1.
It is 0. On the other hand, the rear end of the duct 8 opens at the stern 11 of the hull 2, and this opening is connected to the water spout 1.
2.

Reference numeral 14 denotes an engine, and a propulsion shaft 15 extends rearward from this engine 14. A propulsion propeller 16 is attached to the rear end of 15. Then, if the engine 14 is activated,
A propulsion propeller 16 is driven via the propulsion shaft 15, thereby sucking water into the duct 8 through the water intake port 10 (arrow A in FIGS. 1 and 2), while this water flows through the water spout The water jet propulsion boat 1 is propelled by being ejected from the water jet 12 toward the rear of the hull 2 (arrow B in FIGS. 1 and 2). 1 to 3, reference numeral 18 denotes a propelled ship, and this propelled ship 18 has a resin hull 19, and this hull 19 is integrated with a bow part 20 toward the rear from this bow part 20. Left and right side parts 2 that extend to
1, 21, and a reinforcing plate 22 connecting the lower ends of the left and right side parts 21, 21.
A space surrounded by the reinforcing plate 22 and the reinforcing plate 22 serves as a fitting recess 23.

[0013] The fitting recess 23 is open upward and backward, and has a shape into which the bow 24 of the hull 2 can be removably fitted when the water jet propulsion boat 1 is moved forward. ing. Further, a holding means 26 is provided for holding the water jet propulsion boat 1 fitted into the fitting recess 23 in the fitted state while pressing it forward. This holding means 26 has a pair of left and right bands 27, 27 made of rubber or the like. One end of each of these bands 27 is attached to the reinforcing plate 22.
The other ends are releasably connected to each other by a buckle 28 on the seat 5. When the water jet propulsion boat 1 is propelled in the above-mentioned fitted state, the propelled boat 18 is pushed and moves forward. In other words, the water jet propulsion boat 1 functions as a driving source for the propelled boat 18, and ship 18
will be moved to the desired position.

1 to 4, a rectangular notch 30 is formed in the rear part of the reinforcing plate 22, which is the bottom plate of the fitting recess 23, and as shown in FIGS. 1 to 3, a water jet propulsion When the bow 24 of the boat 1 is fitted into the fitting recess 23, the rear end edge 31 of the reinforcing plate 22 corresponding to the water intake 10, that is, the edge of the notch 30, is positioned forward of the water intake 10. They are separated by a length l. Therefore, when the propelled boat 18 is moved by the water jet propulsion boat 1, even if a large number of vortices 33 are generated one after another in the water 32 from the rear end edge 31 of the reinforcing plate 22, these vortices By the time the vortices 33 reach the water intake 10, they are diffused, weakened, and disappear, so that these vortices 33
It is prevented from entering through the duct 8. Therefore, the propulsion propeller 16 provided in the duct 8
This prevents the occurrence of inconveniences such as deterioration of performance. In the above case, if the thickness of the reinforcing plate 22 is d (approximately 1 cm), the dimension l is preferably about d×(25 to 50).

The reinforcing plate 22 has an upper plate 35 and a lower plate 36 which are separate from each other, as shown in FIG. 7 in a second embodiment described later.
It has a structure in which the upper plate 35 and the lower plate 36 are stacked vertically and bonded with adhesive,
The front part of the upper plate 35 is integrally molded with the upper surface plate of the bow part 20, and the left and right side parts of the upper plate 35 are integrally molded with the respective side walls of the left and right side parts 21 on the fitting recess 23 side. . Further, the front part of the lower plate 36 is integrally molded with the bottom plate of the bow part 20, and the left and right side parts of the upper and lower plates 36 are the same as the left and right side parts 2 of the same.
It is integrally molded on each bottom plate of 1. The front portion of the fitting recess 23 is formed by the upper plate 35 and has a shape that follows the outer surface of the bow 24 of the water jet propulsion boat 1 . In particular, the front end of the fitting recess 23 has a prow 37 of the bow 24.
A locking recess 38 into which the prow 37 is inserted is formed to position the prow 37 vertically and horizontally. Further, as shown in FIG. 1, the front portion of the fitting recess 23 has an arcuate concave shape along the bottom 9 of the bow 24 of the water jet propulsion boat 1. The upper plate 35 and the lower plate 36 are connected to the fitting recess 2.
The front part of the propelled ship 18 has a structure that gradually separates up and down as it moves forward.
Sufficient strength is ensured at the connection between the bow section 20 and the reinforcing plate 22.

In FIG. 3, a protrusion 39 that slightly protrudes downward is formed at the left and right intermediate portions of the rear part of the bottom 9 of the water jet propulsion boat 1.
I'm stuck in it. Then, the reinforcing plate 22 and the protrusion 3
The lower surfaces of the propeller 9 form smooth surfaces on both the front and rear, left and right sides, and are designed to prevent water resistance from increasing during propulsion. Further, when the bow 24 of the water jet propulsion boat 1 is fitted into the fitting recess 23, the bow 24 of the water jet propulsion boat 1 is automatically fitted into the fitting recess 23.
4 is fitted into the front part of the fitting recess 23, and the protrusion 39 is fitted into the notch 30, so that the water jet propulsion boat 1 is positioned with respect to a predetermined position of the propelled ship 18. .

1 to 4, a recess 41 extending left and right is formed on the upper surface of the bow section 20.
1 has three seats 42 arranged side by side on the left and right. Also,
A recess 43 extending back and forth is formed in the upper surface of each side portion 21, and a pair of seats 44 facing each other in the front and back are provided in this recess 43. A crew member 45 on this seat 44 can operate the water jet propulsion boat 1. Additionally, 46 is a handrail. Although the above is based on the illustrated example, in the above configuration, the locking recess 38 is not present, and only the front part of the bottom 9 of the hull 2 of the water jet propulsion boat 1 is fitted into the fitting recess 23. You can.

Each of the following figures shows other embodiments, but since these embodiments have the same configuration as the first embodiment, the common configurations are designated by reference numerals in the drawings. The explanation will be omitted and only the different configurations will be explained. (Second Embodiment) FIGS. 5 to 10 show a second embodiment. According to this, the bar handle 4 of the water jet propulsion boat 1 is supported by the rotating end of the rotating arm 48 that is pivotally supported on the handle support part 3 so as to be vertically movable, and the seat 5 is provided. At this position, a footrest surface 6 is formed in place of this seat 5. A crew member standing on this footrest surface 6 can operate the water jet propulsion boat 1 while gripping the bar handle 4 and moving the rotating arm 48 up and down.

A support piece 50 is provided protruding from the rear end of each of the side parts 21, and one end side of a ladder 51 is pivoted to the support piece 50 by a pivot shaft 52 so as to be vertically movable. Further, a ratchet device 53 is provided which automatically allows the ladder 51 to rotate upward while preventing it from rotating downward. This ratchet device 53 is composed of a gear 54 formed on the protruding end of the support piece 50, and an engaging pawl 55 that is pivotally supported by the ladder 51 and removably engages with the gear 54.

As shown in FIGS. 5 to 7, when the rudder 51 is rotated upward when not in use, the rudder 51 is attached to the stern 11 of the water jet propulsion boat 1 fitted into the fitting recess 23. One end portion 57 of 51 is pressed into contact. The one end portion 57 maintains the fitted state while pressing the water jet propulsion boat 1 fitted into the fitting recess 23 forward. That is, the ladder 51 and the ratchet device 53 also serve as the holding means 26. When pulling out the water jet propulsion boat 1 from the fitting recess 23, the engaging pawl 55 is disengaged from the gear 54, and the rudder 51 is rotated downward as shown in FIG. What is necessary is to open the rear part of 23.

In FIG. 7, a stopper 58 is provided protruding from one end of the ladder 51, and when the ladder 51 is rotated downward by a predetermined amount, the stopper 58 moves against the support piece 50.
, and further downward rotation is prevented. In this way, for example, the crew member underwater 32 can climb onto the propelled ship 18 using the ladder 51.

5 to 9, the reinforcing plate 22 is formed with a rectangular communication port 59 that communicates the water intake port 10 with the lower part of the reinforcing plate 22. As shown in FIGS. The left-right width dimension of the communication port 59 is slightly larger than the water intake port 10, but the front edge 60 of the opening edge of the communication port 59 is spaced forward from the water intake port 10 by a distance l. There is. Therefore, even if a large number of vortices 33 are generated one after another in the water 32 from the front edge 60 of the communication port 59 toward the rear when the propelled vessel 18 is propelled by the water jet propulsion boat 1, these vortices 33 By the time they reach the water intake 10, they are diffused or weakened and disappear, thus preventing these vortices 33 from entering the duct 8 through the water intake 10.

In FIG. 8, the reinforcing plate 22 has a pair of grooves 62, 6 extending in the front and back direction on the left and right sides of the communication port 59.
2 is formed. On the other hand, a protrusion 63 is formed on the bottom 9 of the water jet propulsion boat 1 to fit into the groove 62 when the bow 24 of the water jet propulsion boat 1 is fitted into the fitting recess 23 . That is, the water jet propulsion boat 1 is inserted into the fitting recess 23.
When the bow 24 of the water jet propulsion boat 1 is inserted, the protrusion 63 is automatically fitted into the groove 62, and the water jet propulsion boat 1 is positioned laterally relative to the propelled boat 18. 9 and 10, four handle portions 64 are formed on each of the left and right sides of the propelled vessel 18, and these are used to carry the propelled vessel 18.

(Third Embodiment) FIGS. 11 and 12 show a third embodiment. According to this, the upper surface of the reinforcing plate 22 in the front cross section has a concave shape as a whole, and the bottom 9 of the water jet propulsion boat 1 fits onto this reinforcing plate 22, so that the propelled boat 18 is exposed to water. The jet propulsion boat 1 is positioned laterally and laterally. A communication port 59 is formed in the reinforcing plate 22, and the lower surface of the front edge 60 at the opening edge of the communication port 59 is inclined so as to gradually approach the bottom 9 of the water jet propulsion boat 1 as it goes rearward. ing. Therefore, when the propelled ship 18 moves, the front edge 60
The generation of the vortex 33 behind the vortex 33 is suppressed.

Further, the lower surface of the rear end edge 65 at the opening edge of the above-mentioned communication port 59 is inclined so as to gradually approach the bottom 9 of the water jet propulsion boat 1 as it advances forward. It is considered that the fluid resistance due to the edge 65 is reduced. Note that the position of the rear edge 65 is as follows:
It may be located somewhat forward of the rear edge of the water intake port 10, as shown by the dashed line in FIG. Further, although the above is based on the illustrated example, the fitting recess 23 may be offset to either the left or right side of the hull 19 of the propelled ship 18.

(Fourth Embodiment) FIGS. 13 to 21 show a fourth embodiment. 13, FIG. 15, and FIGS. 18 to 20, 66 is a gunwale. In addition, hand grips 6 are provided on the left and right opening edges of the rear end of the fitting recess 23, respectively.
7 is installed. In particular, as shown in FIG. 15, when the water jet propulsion boat 1 is fitted into the fitting recess 23, the crew member 45 on the water jet propulsion boat 1 grasps the hand grips 67, 67 and holds the water jet. The propulsion boat 1 is pulled into the fitting recess 23.

In FIGS. 18 and 19, when fitting the water jet propulsion boat 1 into the fitting recess 23 as described above,
The front edge of the hull 2 of the water jet propulsion boat 1 has the same fitting recess 23 as above.
A rubber buffer plate 68 is attached to prevent each hull 2, 19 from being damaged even if it comes into contact with the left and right opening edges at the rear end. In addition, as shown in FIG. 18 in particular, another buffer plate 69 having the same function as the buffer plate 68 is attached to the locking recess 3.
It is also located within 8.

13, FIG. 14, FIG. 15, and FIGS. 19 to 21, friction plates 70 are attached to the left and right opening edges of the upper part of the fitting recess 23, respectively. This friction plate 70 is made of resin and has irregularities formed on its surface. and,
In particular, as shown in FIG. 13, when the water jet propulsion boat 1 is pulled deep into the fitting recess 23, the crew member 45 on the water jet propulsion boat 1 grasps the friction plate 70 to prevent the hand from slipping. The water jet propulsion watercraft 1 is pulled into the fitting recess 23 in such a way that the

That is, when the water jet propulsion boat 1 is installed,
First, grasp each hand grip 67 and pull the bow 24 of the water jet propulsion boat 1 into the fitting recess 23, and then
It is sufficient to grasp each friction plate 70 and pull it further into the inner part of the fitting recess 23. Therefore, the work of fitting the water jet propulsion boat 1 into the fitting recess 23 can be done easily. Also,
Each opening edge of the upper part of the fitting recess 23 to which the friction plate 70 is attached is slanted forward, and the upper surface of the friction plate 70, that is, the gripping surface is also slanted forward. Therefore, the hand of the crew member 45 holding the friction plate 70 becomes more difficult to slip on the friction plate 70, and therefore, in this respect as well, the work of fitting the water jet propulsion boat 1 into the fitting recess 23 is facilitated. There is an effect.

FIGS. 13 to 15 and FIGS. 18 to 2
1, support plates 72 are attached to the inner wall 23a of the fitting recess 23 with screws, and these support plates 7
Four protrusions 73 are bonded to each of the two. These protrusions 73 form a horizontal groove 74 extending back and forth,
A vertical groove 75 extending vertically is formed. Note that the support plate 72 and the protrusion 73 may be made of metal or resin, and in particular, the protrusion 73 may be made of rubber.

In particular, in FIGS. 13 and 21, when the water jet propulsion boat 1 is fitted into the fitting recess 23 as described above, the left and right gunwales 76 of the hull 2 of the water jet propulsion boat 1 at the time of fitting are as described above. It fits into each horizontal groove 74, respectively. The horizontal groove 74 serves as a guide when the water jet propulsion boat 1 is inserted into the water jet propulsion boat 1. That is, when the water jet propulsion boat 1 is fitted into the water jet propulsion boat 1, the bow 24 of the water jet propulsion boat 1 tends to lift up due to the weight of the crew member 45, but the horizontal groove 74 suppresses this lifting. 1 can be inserted smoothly.

In particular, as shown in FIG. 21, in order to prevent the bow 24 of the water jet propulsion boat 1 from rising, the horizontal groove 7 is formed from the upper surface of the gunwale 76 when the fitting is completed.
The length L extending from the lower surface of the gunwale 76 to the lower surface of the horizontal groove 74 is longer than the length L extending from the lower surface of the gunwale 76 to the lower surface of the horizontal groove 74.

In particular, in FIG. 18, the holding means 26 is
A pair of left and right bands 27, 27 are provided, each band 27
, 27 are connected at their lower ends to the inner wall 23a, and a ring 78 is attached to the upper end of the left band 27. Also, a hook 7 is attached to the upper end of the band 27 on the right side.
9 is attached. The ring 78 and the hook 79 are each removably locked to a locking hook 80 attached to the inner wall 23a. and,
When the water jet propulsion boat 1 is fitted, if the annular ring 78 and the hook 79 are removed from each locking hook 80 and they are releasably locked to each other, both bands 27, 27 are connected to the water jet propulsion boat 1. The hull 2 of the boat 1 is fixed to the hull 19 side of the propelled boat 18.

FIG. 13, FIG. 14, FIG. 16, FIG. 17, FIG. 19
, and FIG. 20, a first seat 82 is provided at the center of the left and right sides of the recess 41, and second seats 83, 83 are provided on the left and right sides of this first seat 82. On the other hand, a forward facing third seat 84 is provided in each front part of each of the recesses 43, and a portion surrounded by the first to third seats is recessed and serves as a footrest 85. Further, an extension seat 86 is superimposed on the first seat 82, and this extension seat 8
6 is movable onto the footrest 85, particularly as shown in FIG. In addition, in this case, the extension seat 86 is
Four brackets 8 provided on the foot rest section 85 indicated by 3
Supported by 7.

A rear-facing fourth seat 89 is provided at the front and rear midpoints of each of the recesses 43, and a fifth seat 90 is provided at the rear of each of the recesses 43. The space between 90 is a footrest 91.

In particular, as shown in FIGS. 14, 16, and 17, each of the above seats has a front surface formed with a pad 93, and a back surface formed with a substrate 9 that retains the shape of the pad 93.
4, and the pad 93 is made of rubber, sponge,
It is made of resin or the like, and the board 94 is made of FRP.

In FIGS. 13, 19, and 20,
Both the third seat 84 and the fourth seat 89 are the seating portion 8
4a, 89a, and backrest portions 84b, 89b which are pivotally supported by hinges 95 to be vertically movable. Further, the upper ends of the backrest portions 84b and 89b are also pivotally supported by a hinge 95. The seating portion 89a of the fourth seat 89 is supported on slide rails 97 provided on both left and right sides of the recess 43 so as to be slidable back and forth. If the seating part 89a of the fourth seat 89 is slid backward from the above state, each backrest part 84b, 89b will be removed as shown in FIG.
are rotated downward so that they are supported on the slide rail 97.

As shown in FIG. 20, when the extension seat 86 is moved onto the footrest 85, the seating section 89a of the fourth seat 89 is moved backward, and the backrest sections 84b and 89b are rotated downward. , the top surfaces of all the seats are substantially flush with each other, thereby forming a large flat surface.

As shown in FIGS. 13 and 16, a protrusion 9 is provided on the lower surface of the base plate 94 constituting the seating portion 84a of the third seat 84.
8 is integrally molded, and this protrusion 98 fits into a recess 99 connected to the footrest 85. Through this fitting, the third seat 84 is fixed to the hull 19 side, and the fourth seat 84 is fixed to the hull 19 side.
When the seating portion 89a of the seat 89 is slid back and forth, the third seat 84 is prevented from moving accordingly.

In FIGS. 13 and 17, a fitting recess 1 is provided on the lower surface of a substrate 94 constituting the seating portion 89a of the fourth seat 89.
00 is formed. In a normal use state in which the seating portion 89a of the fourth seat 89 moves forward, the fitting recess 100 is removably fitted into the convex portion 101 formed in the recess 43. Due to this fitting, the fourth seat 89 is maintained in the normal use state. Figure 13 and Figure 1
4, 102 is an accessory case, and 103 is an accessory case lid.

19 to 21, the vertical groove 7
5 is provided with a bracket plate 105 that is vertically and removably fitted into the bracket plate 105, and an outboard motor 106 is removably screwed to this bracket plate 105. In this case, the outboard motor 10
The propulsion propeller 107 of 6 is connected to the underwater 32 through the communication port 59.
is submerged in Then, by driving the outboard motor 106, the propelled vessel 18 can self-propel.

In FIGS. 18 and 19, the fitting recess 23
A drain plug 108 is attached to each inner wall 23a. This drain plug 108 can be attached and detached by an operator in the fitting recess 23, and by removing it, water accumulated in the hull 19 of the propelled vessel 18 can be drained.

[0043]

[Effects of the Invention] According to the present invention, when the water jet propulsion boat is fitted into the fitting recess formed in the propelled boat in order to move the propelled boat,
Since the rear edge of the bottom plate of the propelled boat corresponding to the water intake of the water jet propulsion boat is spaced further forward than the water intake, when the propelled boat is moved by the water jet propulsion boat, the Even if a large number of vortices are generated one after another in the water from the rear edge of the bottom plate toward the rear, by the time these vortices reach the water intake port, they will have diffused or been weakened and disappeared. These vortices are prevented from entering the water intake.

Note that instead of separating the rear edge of the bottom plate of the propelled ship corresponding to the water intake port forward of the water intake port as described above, the water intake port is made to communicate with the bottom of the bottom plate. A communication port may be formed in the upper bottom plate, and the front edge of the opening edge of the communication port may be spaced further forward than the water intake port. In this way, when a propelled boat is moved by a water jet propulsion boat, even if a large number of vortices are generated one after another in the water from the front edge of the communication port toward the rear, these vortices will flow into the water intake port. By then, they have diffused or weakened and disappeared, thus preventing these vortices from entering the water intake.

[0045] As described above, in any of the inventions, the above-mentioned vortices are prevented from entering the water intake port, resulting in the inconvenience of deteriorating the performance of the propulsion propeller provided at the back of the water intake port. Therefore, good propulsion of the propelled vessel by the water jet propulsion boat is ensured.

[Brief explanation of the drawing]

FIG. 1 is a side partial sectional view of a first embodiment.

FIG. 2 is a plan view of the first embodiment.

FIG. 3 is a rear view of the first embodiment.

FIG. 4 is a plan view with the water jet propulsion boat removed in the first embodiment.

FIG. 5 is a side partial sectional view of the second embodiment.

FIG. 6 is a plan view of the second embodiment.

FIG. 7 is a partially enlarged view of FIG. 5 in a second embodiment.

FIG. 8 is a sectional view taken along the line 8-8 in FIG. 7 in the second embodiment.

FIG. 9 is a plan view with the water jet propulsion boat removed in the second embodiment.

10 is a sectional view taken along the line 10-10 in FIG. 9 in the second embodiment; FIG.

FIG. 11 is a side partial sectional view of the third embodiment.

FIG. 12 is a sectional view taken along the line 12-12 in FIG. 11 in the third embodiment.

FIG. 13 is a plan view of the water jet propulsion boat in the middle of being fitted in the fourth embodiment.

FIG. 14 is a side view of the front part of the water jet propulsion boat in the middle of insertion in the fourth embodiment.

FIG. 15 is a rear side view of the water jet propulsion boat in the middle of insertion in the fourth embodiment.

FIG. 16 is a sectional view taken along the line 16-16 in FIG. 13 in the fourth embodiment.

FIG. 17 is a sectional view taken along the line 17-17 in FIG. 13 in the fourth embodiment.

FIG. 18 is a rear view of the propelled ship in the fourth embodiment.

FIG. 19 is a perspective view of a propelled ship in a fourth embodiment.

FIG. 20 is a plan view of a propelled ship in a fourth embodiment.

21 is a sectional view taken along the line 21-21 in FIG. 13 in the fourth embodiment; FIG.

[Explanation of symbols]

1 Water jet propulsion boat 2 Hull 8 Duct 9 Bottom of the ship 10 Water intake 11 Stern 12 Water spout 16 Propulsion propeller 18 Propelled ship 19 Hull 22 Reinforcement plate (bottom plate) 23 Fitting recess 24 Bow 30 Notch 31 Trailing edge 32 Underwater 33 Vortex 59 Communication port 60 Front edge

Claims (2)

[Claims] [Claim 1] Water is sucked in from a water intake port formed in the front and rear part of the bottom of the ship, and the water is injected to the rear of the hull and released rearward to the water jet propulsion boat that moves forward and to the propelled ship. In the structure of the fitting part between a water jet propulsion boat and a propelled vessel, the water jet propulsion boat is removably fitted into a fitting recess formed in the above manner, A water jet propulsion boat and a propelled boat are fitted in such a way that the rear end edge of the bottom plate of the fitting recess corresponding to the water intake port is spaced further forward than the water intake port when the water jet propulsion boat is fitted into the water intake port. Departmental structure. [Claim 2] Water is sucked in from a water intake port formed in the front and rear part of the bottom of the ship, and the water is injected to the rear of the hull and released rearward to the water jet propulsion boat that moves forward and to the propelled ship. In the structure of a fitting part between a water jet propulsion boat and a propelled boat, in which the fitting recesses formed in the above-mentioned manner are removably fitted, A communication port is formed in the upper bottom plate to communicate with the water jet, and when the water jet propulsion boat is fitted into the fitting recess of the propelled boat, the front edge of the opening edge of the communication port is located forward of the water intake port. Structure of the fitting part between a water jet propulsion boat and a propelled boat that are separated.