JPH0218193A - small water vehicle - Google Patents

Abstract

PURPOSE:To increase buoyancy, and to enhance the stability in a stationary floating condition by bulging the lower hull board surface of a small size waterborne craft farther outward than the imaginary line connecting the upper end of the rising part with the chine. CONSTITUTION:In a small size waterborne craft 1 (not shown), the flange part 3a in the periphery of the lower hull 3 and the flange part 4a ion the periphery of the upper hull 4 are joined each other to form a rising part 12, so that a craft body 2 (not shown) is constituted. The lower hull 3 has a board surface 3b and a craft bottom surface 3c, and the board surface 3b goes down from the flange part 3a, and forms a chine 3d with the craft bottom surface 3c. And, the board surface 3b of the lower hull 3 is formed so as to be bulged farther outward than the imaginary line L1 connecting the upper end 12c of the rising part 12 with the chine 3d, so that buoyancy is increased. Thus, the stability in a stationary floating condition can be enhanced, and especially the stability at the time of rolling can be increased, enabling the riding comfortableness of crew-member to be improved.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a small water vehicle for one to three people.

(Prior Art) A small water vehicle that can be steered with a handle and travels on water by driving a jet pump with an engine is disclosed in US Pat. No. 3,623,447 and the like.

In this small water vehicle, the rear parts of the lower hull and upper hull are recessed to form a deck for the occupants to rest their feet on, and this deck is open to the rear.

The outer surfaces of the upper hull and the lower hull are formed into substantially vertical planes in the drawings of the above-mentioned publication.

Further, U.S. Patent No. 3,426,724 discloses a wide hull, and the design drawings of Registered Design No. 717592 show that the upper hull and lower hull are overlapped on both sides of the driver's seat so that the hull is slightly raised. A further configuration is disclosed.

(Problems to be Solved) When the small water vehicle travels on water, the bow of the boat rises and the deck tilts toward the stern.

However, when the boat is stationary on the water, the deck is approximately horizontal, and water tends to enter through the stern opening, resulting in poor stability.

To increase stability, there are ways to increase the height of the rising part or to increase the height of the deck around the driver's seat, and to increase the height of the stern plate accordingly. However, at the same time, the center of gravity of the ship also becomes higher.

Furthermore, although increasing the hull width increases stability, it greatly interferes with driving performance.

(Means for Solving the Problems) In order to solve the above problems, the present invention forms the lower hull side surface to bulge outward from an imaginary line connecting the upper end of the rising portion and the chine.

(Function) As a result, buoyancy can be increased without changing the hull width and height dimensions at the side rising portions of the hull, and interference with running performance can be suppressed as much as possible.

(Example) Embodiments of the present invention will be described below based on the accompanying drawings.

FIG. 1 is a plan view of a small water vehicle according to the present invention, and FIG. 2 is a view taken along the line A--A in FIG.

The small water vehicle 1 has a hull 2 formed by joining a flange portion 3a on the periphery of a lower hull 3 and a flange portion 4a on the periphery of an upper hull 4 to each other.

The lower hull 3 has a side surface 3b and a bottom surface 3C, and the side surface 3b descends from the flange portion 3a and forms a chine 3d with the bottom surface 3C.

A pump housing 9 containing a fuel tank 5, an engine 6, a propulsion shaft 7, and an impeller 8 is interposed inside the hull 2 from the front.

The upper hull 4 is provided with an engine hood 4b that can be opened for maintenance and inspection of the fuel tank 5 and engine 6, and behind the engine hood 4b, a handle 10a of a steering device 10 is provided approximately at the center of the hull 2, A deck 4d is formed at the rear of the steering device 10, which is one step lower than the deck 4C in the front half of the boat.

The front edge of the deck 4d is connected to the deck 4c on the front half of the boat via the standing wall 4e, the inner edge of the deck 4d is connected to the driver's seat 11, the outer edge of the deck 4d is connected to the rising part 12,
The rear edge of the deck 4d is open rearward.

As shown in FIG. 2, the rising portion 12 has an inner surface 12a.
and an outer surface 12b. That is, the inner surface 12a is a portion extending diagonally upward from the deck 4d of the upper hull 4 and is connected to the flange portion 4a of the upper hull, and the outer surface 12b is the upper half portion of the gunwale 3b of the lower hull 3. It is connected to the flange portion 3a.

The bent portion between the outer surface 12b and the flange portion 3a substantially forms an upper end portion 12c of the rising portion 12.

The side surface 3b of the lower hull 3 has the upper end portion 12c.
It is formed to bulge outward by Wl from the imaginary line L1 connecting the chine 3d and the chine 3d. Note that W1 indicates the bulge dimension near the waterline WLI, which is set when the small water vehicle 1 has a predetermined number of passengers on board and is not running.

As a result, a space indicated by S1+S2 is formed inside the rising portion 12. In other words, a new space S2 is added to the space S1 formed by the flat side surface.

The operation of the small water vehicle constructed as described above will be described below.

FIGS. 3(a) and 3(b) are action diagrams, and FIG. 3(a) shows a state in which an occupant M is on board the small water vehicle 1 in a stationary floating state. That is, the occupant M uses the steering device 1
Hold the steering wheel 10a of the 0, sit in the driver's seat 11, and place your feet on the deck 4d. This time coincides with the waterline WLI.

Next, the engine 6 is started and the impeller 8 is driven through the propulsion shaft 7.
is rotated to generate a water jet, and this water jet is injected from the stern via the pump housing 9.

The small water vehicle 1 moves forward, and its bow rises under the reaction force of the water surface, and as shown in FIG. 3(b), the waterline WL2 approaches the bottom surface 3c of the boat during planing. That is, a portion of the horizontal forward thrust is divided into a lift force that lifts the boat body 2, and this lift force is combined with the buoyancy force to hold the small water vehicle 1 above the water surface.

FIG. 4 is a comparison diagram of the stability. The stability of this embodiment, in which the side surface of the lower hull is formed to bulge outward, is greater than that of the conventional example, and the difference in maximum stability is especially remarkable. Fourth
The tilt angle θ shown in the figure indicates the restoring force when the boat body 2 is tilted by θ in FIG.

According to this figure, a space (s
t+s2) and the conventional hull space (Sl) is obvious, and the effect of the increased space (S2) is significant.

The present invention provides for example a deck 4 around the driver's seat 11 in a two-seater vehicle.
d is below the water surface, or the hull is tilted and the deck 4
d, the drainage volume 52 of the bulged portion is even more effective.

In addition, as shown in FIG. 2, the virtual line Ll related to the side surface 3b
, L1, that is, the width of the hull 2, is the same as that of the conventional boat, and good planing performance can be maintained.

The present invention is also suitable for small water vehicles that do not include a driver's seat 11.

(Effects of the Invention) As described above, in the small water vehicle of the present invention, the gunwale of the lower hull is bulged outward to increase buoyancy.
The stability in a static floating state is increased, the stability is increased especially when rolling, and the ride comfort for the crew is improved.The height of the boat can be kept small, and the design of the boat becomes easier.

[Brief explanation of the drawing]

Figure 1 is a plan view of a small water vehicle according to the present invention, Figure 2 is a view taken along the line A-A in Figure 1, Figures 3 (a) and (b) are action diagrams, and Figure 4 is a stability diagram. FIG. In addition, in the drawing, 1 is a small water vehicle, 2 is a hull, 3 is a lower hull, 3a is a flange of the lower hull, 3b is a side surface, 3
C is the bottom of the boat, 3d is the chine, 4 is the upper hull, 4a is the flange, 4c is the deck on the front half of the boat, 4d is the deck one step lower than 4c, 4e is the upright wall, 10 is the steering device, 12 is the upright part, 12c is the upper end, and Ll is a virtual line. Figure 4 patent

Claims (1)

[Claims] A chine is formed by the side surface of the lower hull and the bottom surface of the boat,
The lower hull and upper hull are joined together at flange portions on their peripheral edges to form a boat body, a steering device is provided in the center of the boat body, and a deck that is one step lower than the deck of the front half of the boat is formed behind the steering device. In a small water vehicle, the leading edge of this deck is connected to the deck of the front half of the boat via a standing wall, the outer edge of the lower deck is connected to the rising part, and the trailing edge of this deck is opened rearward. A small water vehicle, characterized in that a lower hull side surface of the small water vehicle is bulged outward from an imaginary line connecting the upper end of the rising portion and the chine.