TECHNICAL FIELD

This invention relates in general to ships or boats having floats for extending the water contact surface, more specifically to structure adapted to be received by a self-propelled jet<-type watercraft.

BACKGROUND ART

Previously, jet-type watercraft, such as commonly known by their registered trademark "Jet Ski", manufac- tured by Kawasaki Jukogyp Kabushiki Kaisha of Kobe, Japan, have had an inherent problem of instability in the water. This includes when it is at rest, climbing aboard and getting underway, or at very slow speeds.

Further attempts have been made to utilize other watercraft with extended side floats. A search of the prior art did not disclose any patents that read directly on the claims of the instant invention, however, the following U.S. Patents were considered related:

PATENT NO. INVENTOR ISSUED 4,320,713 Nishida, et al 23 March 1982

3,974,535 Boulens 17 August 1976

3,756,189 Yutzler 4 September 1973

3,483,844 Trautwein 16 December 1969

Nishida et al teaches a pivotal float on each side of a "Jet Ski" that rotates on a shaft allowing retraction for stowage. The floats are locked in two basic positions, or may be utilized at any angular dis¬ placement therebetween. The floats are triangular with the front end exposed from the water. When the water¬ craft is planing each float is exposed entirely on the surface. About one third of the structure is behind the watercraft extending the length thereof.

Boulens utilizes a spherical shaped boat hull with the fore part extending above the waterline. Tri¬ angular shaped lee-boards extend from each side and to the rear as means to increase stability.

Yutzler takes advantage of three pontoons detach- ably connected to a motorcycle body. The pontoons ex¬ tend the surface of the craft to the side, however, no hull is present therebetween the full length. Trautwein accomplishes a watercraft using a cent¬ rally located passenger carrying member and a pair of outwardly extending supporting floats. Steering is accomplished by the use of a steerable float in the front. The outwardly depending floats comprise the main structure.

It will be seen that attempts have been made to utilize delta shaped floats for extending the width of the watercraft, however, the combination of removable utility has not been approached.

DISCLOSURE OF THE INVENTION

A watercraft, such as commonly known by its trade- marked name "Jet Ski", or any similar boat operated singly from a standing position using a jet of water for pro¬ pulsion has the inherent problem of stability when at

rest or at slow speeds. Of particular importance is the difficulty in mounting such a craft when in the water, as the stability is achieved only at higher speeds when the dynamic pressure of the water reacts with the hull when moving, creating lift and the gyro effect of the operator. When the craft is immobile, danger of cap¬ sizing becomes apparent in both slowing down to a stop and particularly when an operator is boarding thereupon in open water. The watercraft was purposely made with a minimum amount of surface area in the hull to maximize speed and manuverability, also, the operator is normally in a standing position to further this objective.

It is, therefore, the primary object of the in- vention to fill the need to provide stabilization of the craft at all conditions in the water making the vehicle usable by those with a lesser range of skill and increased ease of the operation.

An important object of the invention allows easy attachment and removal of the extended surface with absolutely no modification to the watercraft. This is accomplished by using the parting flange of the watercraft as the attaching surface and slipping a hull extension on each side. This arrangement is held in place by a novel wedge that is slipped over the flange forcing it into a mating surface in the hull. This wedge is 80 percent the length of the hull making the attach¬ ment rigid and secure. The hull is configured exactly the same as the side of the watercraft making attachment easy and uniform. Since the surface in contact is very large and sufficient, structural integrity is afforded, no visual affects are seen when the devices are removed and replaced repeatably.

The invention in another object provides a planing surface on the hull that enhances the stability of the craft without effectively increasing the drag. This is

accomplished by continuing the surface of the underside of the hull in a smooth gradual transition, also, by adding an internal radial contour on the underside. When the craft is moving at high speed a greater portion of the apparatus is out of the water eliminating most of the surface contact. Some slight change in operating characteristics are realized at low speeds and in tight cornering, however, little overall effect is produced. Still another object of the invention provides simple and obvious attachment procedures. Since the purpose of the structure and its physical location is apparent to the user, the wedge attachment becomes re¬ cognizable. As the groove is loosely fit, the installer having only one other separable element easily finds the utility and is able to install the devices without the use of instructions or training.

Yet another object of the invention is in the ease and simplicity of construction. Since the device con¬ sists of but one basic element with a few supportive attachment structures the invention becomes cost effective and easy to produce in quantity.

These and other objects and advantages of the pre¬ sent invention will become apparent from the subsequent detailed description of the preferred embodiment and the appended claims taken in conjunction with the accompany¬ ing drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGURE 1 is a partial isometric view of the pre¬ ferred embodiment attached to a watercraft.

FIGURE 2 is a side elevational view of the pre¬ ferred embodiment.

FIGURE 3 is an end view of the preferred embodiment. FIGURE 4 is a cross-sectional view taken along lines 4-4 of FIGURE 2.

FIGURE 5 is a partial isometric view of the pre¬ ferred embodiment removed from the watercraft.

FIGURE 6 is a plan view of the preferred embodiment.

FIGURE 7 is a cross-sectional view taken along lines 7-7 of FIGURE 8.

FIGURE 8 is a plan view of the tapered wedge de¬ picted singularly.

FIGURE 9 is a side view of the preferred embodiment.

FIGURE 10 is a cross-sectional view taken along lines 10-10 of FIGURE 9.

FIGURE 11 is a cross-sectional view taken along lines 11-11 of FIGURE 9.

FIGURE 12 is a cross-sectional view taken along lines 12-12 of FIGURE 9.

BEST MODE FOR CARRYING OUT THE INVENTION

The best mode for carrying out the invention is presented in terms of a preferred embodiment. The pre- ferred embodiment, as shown in FIGURES 1 through 12 is comprised of a pair of opposed trapezium shaped hulls 20. These hulls 20 are identical, except for the oppos¬ ite hand configuration as one mounts on each side of the watercraft in opposite orientation. The hulls 20 require an irregular shaped surface on the inside to be compatible with the watercraft and a smooth surface on the outside with contoured radius to blend into the scheme extending the exterior to achieve a low drag coefficient. Any material and method of con- struction may be used that will allow this configuration to be obtained, such as metal, wood, fiberglass, and the like, with thermoplastic being preferred. The preferred embodiment employs a thermoplastic, such as polyethylene or may also use butyrate, vinyl, polystyrene, polycarbon- ate, acetal or urethane, or the like. A measured amount of powdered or liquid polyethylene, or the like, is loaded

into hollow molds the shape of the hull 20. The mold is heated and rotated simultaneously on two axes where the hot mold fuses the plastisol into a gel, causing it to cover all surfaces with a uniform thickness. The mold is then cooled and the hull is removed. This pro¬ cess of rotational molding is sometimes referred to as rotomolding. The outer skin 22 may also be formed of a molded plastic material, such as fiberglass and has a smooth uninterrupted surface on the external parts. Each hull 20 has a smooth outside shape following the lines of the watercraft on the tapered front 30 and pitching gradually away from the side to a wider base at the stern. The top plane 26 is generally contoured, blending in shape to the side of the watercraft. The underside, or bottom 28, continues the shape of the hull in an internal radial contoured manner, as depicted in FIGURES 3 and 4, extending the surface gradually in such a shape that, when speeds are increased, the hull is lifted almost out of the water by planing action, while at lower speeds the shape allows minimum drag to be ex¬ perienced. The appended side 32 contiguously engages the side of the watercraft and contains an attaching groove 34 therein with an internal trough 36 downwardly config¬ ured as part of the groove 34. The rear 38 is forwardly sloping duplicating the angular shape of the watercraft and the outwardly depending side 40 is shaped with a pair of angular apexes in the form of a wing which ex¬ tends the width of the watercraft when the hulls 20 are attached in opposite pairs. The top 26 and bottom 28 are. contoured to a vertical.leading edge 42 extending the shape of the bottom of the watercraft in a hydro- dynamic manner providing stabilization to the craft while in operation by extending the overall width of the area in contact with the water. Each hull 20 is hollow and watertight making the

inside a floatation chamber creating buoyancy of the structure. The inside may be a void with only air in the chamber, or is filled with a cellular plastic, such as polyurethane in a rigid foam 24 or any suitable material, such as polystyrene, balsa wood, cork, and the like. In the preferred embodiment polyurethane is utilized due to its adaptability and ease of foaming in place. While with some embodiments, the floatation material is formed first and the hull built around them, the foamed in place material allows the hull 20 to be fabricated first and the material added later. With the preferred foam material urethane bonds are formed through reaction of alcoholic hydroxyl groups and isocyanate groups. The material in liquid state expands- to fill the void, using a catalyst and blowing agent, becoming rigid with an extremely low density filling the entire inside area completely.

A tapered wedge 44 is utilized on each hull 20 for attachment. This wedge 44 contains a pair of flat sides that are mounted planar to the body of the watercraft with a tapered top and bottom, a flat front and a slop¬ ing rear. The wedge 44 is placed within the groove 34. The wedge 44 further contains removal means in the form of a hole 46 near the sloping rear end with a pair of cavities 48 connecting the hole 46 to the extreme rear. A looped cord 50 is positioned within the hole 46 and disposed inside the cavities 48 providing completely clear sides with the balance of the looped cord 50 at the end making it easily graspable. The wedge 44 may be constructed of any plastic material, wood, metal, or the like, with a molded plastic being preferred.

The installing of the hulls 20 to the watercraft is extremely simple and requires absolutely no modification to the craft itself. The hull 20 is slipped from the rear over the parting line of the craft. This parting line is the intersection of the top and bottom shell of

the so called "Jet Ski" and is attached securely together. This line has a downwardly depending flange all the way around and is trimmed uniformly. The hull 20 is slipped over this flange through the groove 34 with the flange by penetrating into the hull trough 36. When the hull 20 is positioned, even with the sloping rear end, the wedge 44 is forced into the remainder of the groove 34. This wedging action places friction on the joint and holds the hull 20 securely onto the craft by compression between the members. In addition to the compression, additional holding security may be obtained by attaching a detent mechanism (not shown) . One section of the mechanism is located on the surface of the wedge 44 while the mating section is positioned on the hull 20 so that the two sections engage when the wedge 44 is fully inserted into the hull 20. The wedge 44 has the rear end tapered at the same angle as the watercraft, blending into conformance of the contour. The looped cord pro¬ trudes out of the groove 34 allowing the wedge to be removed for dissembly.

It will be seen that the assembly and dissembly of the device is extremely simple and easy to accomplish, and may be done at the launching site, allowing the craft to be transported easily without the extension in place. In order to assure that the hulls 20 and wedge 44 stay in place, securing means are provided in the form of a strap 52 that is fixed on one end to the hull 20 and the other to a protruding member on the watercraft such as the rear parting line. A hook, or similarly shaped member, is utilized for the connection that is configured in such a manner as to be compatible with a feature of the water¬ craft. Another embodiment attached on both ends to the hull 20. In any event, this strap 52 is positioned dia¬ gonally across the end of the tapered wedge 22 captivating it is place in the event itshould loosen and move from

its wedged position. Other embodiments may be used in this area with equal ease, as long as the captivating feature is included.

In operation the watercraft is transported in the usual manner by portable trailers, or the like, and prior to launching the wings are installed, as previously described, one on each side with the wedge 44 tightly secured in place and the strap 52 connecting across the element. Removal is accomplished in the opposite manner and storage may be completed on the trailer or the trans¬ portation mode. If the craft is handled singly, the in¬ vention may be left in place permanently.

While the invention has been described in complete detail and pictorially shown in the accompanying draw- ings, it is not to be limited to such details, since many changes and modifications may be in the invention without departing from the spirit and the scope thereof. Hence, it is described to cover any and all modifications and forms which may come within the language and scope of the appended claims.