Boat hull strake design

Abstract

A system for increasing the buoyancy of a boat operating in the water and to reduce the wetted-surface-friction of the water against the hull of the boat. The system includes a multiple of strakes attached to the bottom side of the boat. The strakes are instrumental in creating a multitude of bubbles on which the hull of the boat will ride which increases the efficiency of the power of the motor or motors powering the boat. The strakes are arranged in series along the hull of the boat and can increase in size from the bow of the boat to the stern. The strakes are also increasing in depth from the bow of the boat to the stern. The strakes may be attached to the boat as a retro-fit or may be added when manufacturing the boat.

Description

BACKGROUND OF THE INVENTION

Designers and manufactures of planning boat hulls have for years used a variety of means to attempt to have the least amount of solid water in contact with the hull of a boat when planning on the hull surface. Probably the earliest designs for hulls on boats without the usual framing, utilizing overlapping planking, which is known as “Lapstrake” or “Clinker” style hulls, which were originally created by the Vikings. This construction method of the overlapping planking was applied by some early wooden boat builders to eliminate conventional framing and also reduce the weight for planning hulls, which incidentally created some bubbles for probably the very first time, which reduced some of the ordinary water-to hull friction from solid water under the hull. Others have tried cross-wise steps in their hulls to draw air under the hull and create bubbles to reduce friction. Still others have tried length-wise air tunnels and some bubble creation, again to reduce friction. Some have tried sponson-like configurations with the same objective to reduce friction between the boat hull and the solid water. The commonly used strakes in today's boat hulls were originally created to assist the then new Deep-V hull designs that could not otherwise have a satisfactory planning surface. Those now in use in a variety of planning hulls are designed to force water out and away from the hull for increased hull lift out of the water for friction reduction. Some of them extend too close to the bow of small boats and in rough water can catch a wave and cause a nasty, sudden and dangerous abrupt turning of the boat.

BRIEF DESCRIPTION OF THE INVENTION

The inventive use of attachable strakes, or designed into the hull, forces the normally outward flowing water back under the hull and this forced redirection of the water back under the hull, a massive bed of foam bubbles is created resulting in reducing the original planning surface friction to a minimum. This inventive concept uses strakes which are designed to put the largest possible amount of air containing bubbles under the largest amount of the otherwise planning surfaces. By using multiple, uniquely surfaced, inwardly canted and tapered strakes with added ridges and steps, a huge amount of bubbles is created and they are kept under the hull as long as possible. The strakes are also directed to those areas under the hull where they are most desired. This enables the hull to ride with very low friction thereby reducing fuel consumption and the related pollution of the environment for maximum efficiency and conservation in today's world.

These planning area strake features can be used in a variety of shapes and configurations. Other air introduction or bubble creating designs require restricted hull designs to enable their use. This is the first inventive concept that will get boat hulls onto a plane mode sooner, with less power required to do so and have the least amount of surface friction regardless of the planning speed at which the boat is operating. For the first time theses bubble creating strakes can be used on any manufacture's hull for complete freedom of hull design compared to all present designs. They can also be manufactured separately to be added to hulls already in service, as a retro-fit, with huge gains for their owner, for increased speed and performance, economy and reduction in pollution. It is also a well known fact that salt water, when churned, easily creates bubbles which can be seen by watching a boat, when traveling in salt water, the propeller churns up the salt in the water and the boat leaves a long trail of bubbles in its wake. The inventive concept takes advantage of this phenomenon. There are also known semi-displacement hulls which can get up to plane infrequently. Now that higher powered engines are available, and newer hull forms with large planning areas are being used, these boats also need the advantage of the bubble-ride concept.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A shows a prior art bottom of a boat;

FIG. 1B is a prior art back view of a boat;

FIG. 1C is side view of a prior art boat;

FIG. 1 illustrates a side view of a boat with strakes attached;

FIG. 2 shows the action of the strakes;

FIG. 3 is a perspective view of the strakes themselves;

FIG. 4 is a bottom view of the strakes while increasing in size;

FIG. 5 is a bottom view of a boat with a multiple of strakes;

FIG. 6 is a rear view of a boat with a strake line attached to the Bottom;

FIG. 7 is a magnified view of a single back end of a strake.

FIG. 8 illustrates the creation and the concentration of the bubbles;

FIG. 9 is the rear view of the hull of FIG. 8.

DETAILED DESCRIPTION OF THE INVENTION

FIGS. 1A-1C illustrate a conventional design of a boat showing The bottom of a boat, a rear view and a side view.

FIG. 1 illustrates a side view of a boat having several strakes attached to the bottom from the keel shown at 2, the side of the boat hull 3 and further up the side shown at 4. These strake series are space apart from each in a horizontal manner and they can be of different lengths.

FIG. 2 shows how the individual strakes 5 create a a stream of bubbles 5. The individual strakes are slanted upwardly as seen from the direction of the travel of the boat. This slant is especially constructed because , once the water flow passes over the strakes, it creates somewhat of a venturi effect which aids in the creation of the bubbles which is the basic aim of the inventive concept.

FIG. 3 is a perspective view of a line of strakes where the slant of the individual strakes can be observed. The individual strakes are also canted relative to the hull of the boat or expressed differently, the trailing edge of the strakes are angled toward the keel and the steps are progressively thicker toward the stem and they are higher on the chine-side than the keel side.

FIG. 4 shows a line or series of strakes where an increase in size along the line can be observed. The increase in size as shown at 5, 6 7 and 8 starts in the vicinity of the bow of the boat hull and keeps increasing toward the rear of the hull. It also can be seen that the strakes are getting wider toward the stem so that water confined between the series of strakes has less and less space to move toward the stem and, hence, the spillover that is caused, creates more bubbles than would strakes with parallel sides. The strakes of themselves are adding more bubbles under the hull. The strakes are progressively deeper from the bow toward the stern because the bed of bubbles is being continually added to as the as the hull goes through the water and the increased holding and added confining ability of the deeper and deeper strakes is essential for maintaining the largest possible bed of bubbles. By choosing an increase in size, the effect of the increase in bubble intensity is multiplied which aids in reducing the friction of the hull surface against the stream of water.

FIG. 5 illustrates the bottom of a boat hull and the strakes as attached to the hull are shown at 2 at the lower most edge of the hull and increasing the distance from the lower most edge at 3 and then 4. This view also shows the different sizes of the individual strakes in a series as the sizes increase from the bow of the hull to the rear. This FIG. 5 also shows that the size of each longitudinal row increases from the chine of the hull and down to the keel of the hull.

FIG. 6 illustrates the rear of the boat hull. Again the line of the strakes can seen from the bottom at 2 and up the sides at 3 and 4. The circle 9 shows an individual strake which is more clearly shown in FIG. 7. In this view it can be seen that the strakes 10 are canted relative to the bottom of the hull. That is, the bottom of the strake 10 and all of the strakes is retained in an angled position relative to a horizontal plane. This then can be termed that the strakes are canted.

FIG. 8 shows the creation of the bubbles by the various

Claims

1. A system to increase the buoyancy of a boat, said system includes a series of longitudinal strakes attached to a hull of said boat, said strakes being slanted and canted relative to said hull of said boat to thereby create bubbles as said boat moves through the water, said bubbles create said buoyancy and reduce friction of the water against said hull of said boat.

2. The system of claim 1, wherein there is a multiple of said series,

3. The system of claim 1, wherein there are at least three series of said stakes on each side of said hull.

4. The system of claim 1, wherein said stakes in said series increase in width from a bow to a stern of said hull.

5. The system of claim 1, wherein said stakes in said series increase in depth from a bow to a stern of said hull.

6. The system of claim 3, wherein said series of said strakes diminish in size from the keel of said hull and up the chimes of said hull.

7. The system of claim 1, wherein a series of steps are incorporated into said strakes.