JPH0696397B2 - Small jet propulsion boat - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a small jet propulsion boat mainly for one or two passengers and traveling at high speed on the sea, and particularly excellent straight line high speed traveling and sharp turning. It relates to what made possible.

(Prior Art) Generally, in a ship, straightening is improved by increasing the port side length,
If the straightness is improved, the turning performance is reduced. However, since the specifications of these vessels are determined at the time of design and do not change afterwards, it was not easy to achieve both straight running and turning characteristics.

(Object of the Invention) An object of the present invention is to provide a jet propulsion type small planing boat capable of simultaneously satisfying the contradictory requirements of the straightness and turning of the hull.

(Structure of the Invention) The present invention forms a straddle-type seat in the center of the rear part of the hull in the width direction, and installs an operation handle on the front side of the hull. An outer chine formed at the connecting portion with the bottom plate of the ship and an inner chine formed inside thereof form a double inner / outer chine, the outer chine being parallel to each other at the rear of the hull and the hull at the front of the hull. It is curved so as to approach the center line, and the inner chine is formed at a position closer to the outer chine than the center line in the hull length direction.

Further, the bottom of the hull at the rear side of the center of the hull may be formed in a flat shape having a small lateral movement resistance.

With the above configuration, the weight of the operator can be moved back and forth, and the water is drained by the inner chine when going straight to reduce the water line area and reduce the propulsion resistance to improve straightness.

In addition, since the front side of the outer chine is curved so as to approach the hull centerline, the front bending part of the outer chine is submerged in water when the operator moves his / her weight to the front side during turning, and the braking action is As a result, make a good sharp turn. Further, during turning, a large pressure is generated between the outer chine and the inner chine that are formed close to each other on the outer side of the turning, and a large pressure is also generated on the inclined surface of the ship bottom on the opposite side, which stabilizes the inclined state. To be kept.

In addition, when the driver turns his / her weight rearward and laterally during turning, the rear part of the outer chine sinks in the water to drain the water, and a large pressure is applied between the outer chine and the inner chine that are formed close to each other. Since it occurs, it is possible to stably incline to a large inclination angle, which enables a high-speed steep turn.

In addition, by forming the bottom of the hull behind the center of the hull into a flat shape with low lateral movement resistance, when the pilot moves his weight forward, the hull of the rear side slips sideways when the driver moves his weight forward. The turning is done well.

(Embodiment) In FIGS. 1 to 3, a hull 100 comprises a bottom plate 20 and a side plate 8
0 and the portion surrounded by the upper deck 21 and the stern plate 70 formed on the front side of the center of the hull are configured to have a drainage volume, and substantially in the portion surrounded by the bottom plate 20 and the upper deck 21. A closed engine room is formed.
Further, a seat 50 is formed so as to project at a central portion in the ship width direction at a rear portion thereof, and a foot deck 30 that opens to the stern end is formed between the seat 50 and the gun flannel 88 on both sides. The foot deck 30 and the lower side of the seat 50 are also configured to have a drainage volume.

A handle support portion 61 is fixedly mounted on the upper deck 21, and a handle 60 is formed on the upper end portion thereof. The deck 21 at the portion where the handle support portion 61 is provided is formed to project and a buoyancy space is formed under the same. An engine room is formed. Also, the operator 11 on the seat 50 holds the above-mentioned handle 60 with his foot on the foot deck 30 and
100 is operated, and from this state, the operator 11 stands up and can move his / her weight back and forth and left and right.

The propeller (not shown) is rotated by the engine in the engine room to suck water from the water suction port on the bottom of the ship,
A turning force and a propulsive force are generated by injecting water backward from a nozzle 71 that swings horizontally in the stern through a flow path formed below 50.

The shape of the ship bottom is configured as shown in FIGS. 3 and 5 (A) and (B). That is, the bottom plate 20 is composed of the keel 22 at the center in the width direction and the inclined surfaces on both sides of the keel 22, and the inner and outer double chains 28, 29 are formed on the bottom 20 of the ship, and the outer chine 28 is substantially vertical to the side plate 80. And a substantially horizontal ship bottom plate 89. In addition, the inner chine 29 is formed so as to project in a triangular shape from the inclined surface of the bottom of the ship in a cross section. Both of the chains 28 and 29 are formed such that both sides are parallel to each other at the rear side of the central portion in the lengthwise direction of the hull and are curved so that the front side of the central portion approaches the center line of the hull.

The keel 22 is formed so that the width thereof becomes gradually narrower in the front side than the central portion in the longitudinal direction of the hull, and the inclined surfaces on both sides of the keel 22 are set so that the inclination angle thereof gradually increases, and the keel 22 is entirely V. The shape is close to the shape, and the width of the keel 22 is wider on the rear side than the central portion, and the inclination angles θ of the inclined surfaces on both sides of the keel 22 are set to be small, so that the overall shape is flat. The inclination angle θ is set to about 15 °, and the width of the keel 22 is set to about 1/4 of the ship width.

In the above configuration, the center of gravity G _{0 when the} operator 11 is on is set rearward from the central portion in the longitudinal direction of the hull, and the water line area shape 23 when going straight is drained by the inner chine 29 and The shape is as shown by the diagonal lines in FIGS. 5 (A) and 5 (B). That is, the inner chine 29 drains water to reduce the area of the water line, and the center of gravity G ₀ is on the rear side, and the flat bottom of the rear part occupies a large proportion of the total water line area, and the bottom of the ship is relatively flat. Therefore, the propulsion resistance is small. The distribution of the pressure received from the water on the bottom of the ship when going straight is shown in Fig. 4 (A) and (B).
As shown by the curve 24 in FIGS. 6A and 6B, the pressure in the widthwise central portion and the inner chine 29 is high, and the pressure in the lengthwise front portion is high.

On the other hand, at the time of turning turn, when the operator 11 stands up and moves his / her weight forward and steers to a predetermined steep angle, the hull inclines and the outer chine 28 as shown in FIG. 5 (A). The front part of the is immersed in water and drains water. At this time, since the front part of the outer chine 28 is curved so as to approach the hull center line, the brake action is exerted by immersion in the water to enable a sharp turn, and the outer chine 28 has a steep angle ( Since the cross-sectional shape is formed at a substantially right angle, the resistance against tilting (difficulty in overturning) is large.

The pressure distribution is as shown by the curve 25A in FIGS. 4 (A) and 6 (A), and a large pressure is generated in the outer chine 28 and the inner chine 29, and on the opposite ship bottom slope. Also, a large pressure is generated, which keeps the tilted state stable. Further, the waterline area shape 27A in the inclined state is formed so as to be inclined between one side portion on the front side and the other end portion on the rear side as shown in FIG. 5 (A).

To tilt the hull, the operator 11 shifts the weight forward as described above, which results in the center of gravity G ₀ moving to G ₁ . The center of pressure are longitudinally B ₀ in the straight traveling state, next to B ₁ represents an inclined state, as the distance between the center of gravity was l ₀ in the result rectilinear state, l ₀ is greater than the distance in the inclined state
It becomes l ₁ , and the rear ship bottom is formed flat and the lateral movement resistance is small, so the front ship bottom is braked, and the rear ship bottom slides sideways to make a sharp turn (spin turn). In order to stably perform such a sharp turn, the handlebar support portion 61 that supports the handlebar 60 is fixedly attached to the hull, and the operator 11 can handle the handlebar 60.
By gripping, the posture on the hull can be maintained.

When the hull is tilted by moving its weight rearward in order to make a sharp turn when traveling straight at high speed, the rear part of the outer chine 28 is immersed in the water as shown in FIG. 4 (B). Since the outer chine 28 is formed at a steep angle (substantially right angle), the resistance against tilting (difficulty of overturning) is great. The pressure distribution is as shown by the curve 25B in FIGS. 4 (B) and 6 (B), and a large pressure is generated at the outer chine 28 and the inner chine 29, and at the opposite ship bottom slope. Also, a large pressure is generated, which keeps the tilted state stable. Further, the water line area shape 27B in the inclined state is biased to the inclined side as shown in FIG. 5 (B). In such a state, a small turn at high speed, a so-called edging turn is made.

When the weight is moved to the rear side to tilt the hull, the center of gravity G ₀ shifts to G ₂ . The center of pressure in the lengthwise direction is B _{0 in the} straight traveling state and B _{2 in the} leaning state.As a result, the distance from the center of gravity position in the straight traveling state was l ₀ , but in the leaning state the distance l _{2 is} smaller than l _0. Becomes Therefore, a stable high speed small turn can be performed by moving the weight toward the side.

(Effects of the Invention) As described above, according to the present invention, the weight of the operator can be moved forward and backward, and the water is drained by the inner chine when going straight to reduce the water line area and reduce the propulsion resistance. It is made smaller to improve straightness.

In addition, since the front side of the outer chine is curved so as to approach the hull centerline, the front bending part of the outer chine is submerged in water when the operator moves his / her weight to the front side during turning, and the braking action is As a result, make a good sharp turn. Further, during turning, a large pressure is generated between the outer chine and the inner chine that are formed close to each other on the outer side of the turning, and a large pressure is also generated on the inclined surface of the ship bottom on the opposite side, which stabilizes the inclined state. To be kept.

In addition, when the driver turns his / her weight rearward and laterally during turning, the rear part of the outer chine sinks in the water to drain the water, and a large pressure is applied between the outer chine and the inner chine that are formed close to each other. Since it occurs, it is possible to stably incline to a large inclination angle, which enables a high-speed steep turn.

In addition, by forming the bottom of the hull behind the center of the hull into a flat shape with low lateral movement resistance, when the pilot moves his weight forward, the hull of the rear side slips sideways when the driver moves his weight forward. The turning is done well.

[Brief description of drawings]

1 is a plan view showing an embodiment of the present invention, FIG. 2 is a side view thereof, FIG. 3 is a rear view thereof, and FIGS. 4 (A) and 4 (B) are pressure distribution diagrams in a hull cross-sectional shape, respectively. 5 (A) and 5 (B) are bottom views showing the waterline area shape of the hull, FIG.
Figures (A) and (B) are pressure distribution diagrams in the longitudinal direction of the hull. 100 …… hull, 11 …… pilot, 20 …… bottom plate, 22 …… keel, 23, 27A, 27B …… water line area shape line, 24, 25A, 25B ……
Pressure distribution curve, 28 …… outer chine, 29 …… inner chine, 30 …… foot deck, 50 …… seat, 60 …… handle, 61 …… handle support.

Claims (2)

[Claims] Claims: 1. A straddle-type seat is formed in the center of the rear part of the hull in the width direction, and an operation handle is installed on the front side of the hull, and foot decks are formed on both sides of this seat. Inner and outer double chains are formed by the outer chine formed in the connecting part and the inner chine formed in the inner part, and the outer chines are parallel to each other at the rear part of the hull and approach the hull centerline at the front part of the hull. A small jet propulsion boat characterized in that the inner chine is formed closer to the outer chine than the centerline in the lengthwise direction of the hull. 2. A small jet propulsion watercraft according to claim 1, wherein the bottom of the hull rearward of the center of the hull is formed in a flat shape having a small lateral movement resistance.