US20070012235A1

US20070012235A1 - Boat hull with roll stability at low or high speeds

Info

Publication number: US20070012235A1
Application number: US11/510,795
Authority: US
Inventors: Robert Askew
Original assignee: Individual
Current assignee: Individual
Priority date: 2005-07-18
Filing date: 2006-08-28
Publication date: 2007-01-18
Also published as: CA2552117A1; US20070012234A1

Abstract

A boat hull comprises a transom and a bow; a substantially flat delta bottom surface; left and right sidewalls extending from the transom and converging to meet at the bow; left and right chines formed between the left sidewall and the bottom surface, and between the right sidewall and the bottom surface, respectively, the chines extending from the transom to the bow; and a planing area extending from the transom and a landing area extending from the bow. The chines and the bottom surface are substantially flat in the planing area. The angular bottom portions join the chines and the bottom surface. The angular bottom portions have a deadrise increasing from the transom toward the bow.

Description

RELATED APPLICATION

This is a continuation-in-part of application serial no. 11/452,289, filed Jun. 14, 2006, which claims the priority benefit of provisional application Ser. No. 60/699,915, filed Jul. 18, 2005, both of which are hereby incorporated by reference.

FIELD OF THE INVENTION

The present invention relates generally to a boat hull and particularly to a deep V hull that provides roll stability at low or high speeds.

BACKGROUND OF THE INVENTION

Displacement hulls do not promote planing and travel through the water at limited lower speeds. Planing hulls allow the boat to rise higher above the water at high speeds. Deep “V” hulls are planing hulls that provide a smooth and stable ride even in rough water at high speeds. Deep V hulls provide better splitting into the waves and less slamming at higher speeds. However, deep V hulls are very wallowing at slow speeds and at rest, rocking around badly when sitting at a dock or traveling at really slow speeds.

OBJECTS AND SUMMARY OF THE INVENTION

It is therefore an object of the present invention to provide a boat hull that provides stability at both high and low speeds, and at rest. The present invention provides extremely sharp entries at high speeds, while retaining good roll stability at slow speed, and at rest.
In summary, the present invention provides a boat hull, comprising a transom and a bow; left and right sidewalls extending from the transom and converging to meet at the bow; a substantially flat delta bottom surface extending from the transom toward the bow; left and right chines formed between the left sidewall and the bottom surface, and between the right sidewall and the bottom surface, respectively, the chines extending from the transom to the bow. The flat delta bottom surface extends to about 75-80% of the length of the chines. The chines and the bottom surface are substantially horizontal at the transom, comprising about 35-65% of the width of the hull at the transom.
The present invention also provides a boat hull, comprising a transom and a bow; a substantially flat delta bottom surface; left and right sidewalls extending from the transom and converging to meet at the bow; left and right chines formed between the left sidewall and the bottom surface, and between the right sidewall and the bottom surface, respectively, the chines extending from the transom to the bow; and a planing area extending from the transom and a landing area extending from the bow. The chines and the bottom surface are substantially flat in the planing area. The angular bottom portions join the chines and the bottom surface. The angular bottom portions have a deadrise increasing from the transom toward the bow.
These and other objects of the present invention will become apparent from the following detailed description.

BRIEF DESCRIPTIONS OF THE DRAWINGS

FIG. 1 is a starboard side elevational view of a boat hull made in accordance with the present invention.
FIG. 2 is a front elevational view of the boat hull of FIG. 1, showing the five transverse cross-sections taken along the length of the hull between the stem at the bow where the chines start and the stern where the chines end.
FIGS. 2A and 2B show the variations from the horizontal of the delta bottom surface and the horizontal surfaces at the transom.
FIG. 3 is a bottom plan view of FIG. 1, showing the chines and the flat delta bottom surface symmetrical along the longitudinal axis of the boat hull.

DETAILED DESCRIPTION OF THE INVENTION

A boat hull 2 made in accordance with the present invention is disclosed in FIGS. 1, 2 and 3. The boat hull 2 includes a bow 4 and a transom 6. Left and right sidewalls 8 and 10 extend from the transom 6 to the bow 4. Left and right chines 12 and 14 extend from the transom 6 toward the bow 4.
For reference purposes, cross-sectional lines are drawn perpendicular to the center line 16 of the hull at equally spaced intervals. The cross-sectional lines are designated as A, B, C, D and E. The cross-sectional lines divide the length of the hull along the chines into four equal parts, as best shown in FIG. 1.
A flat delta bottom surface 18 extends from the transom 6 at section line E toward the bow and ends at section line B, comprising about 75% of the chine length. The flat delta bottom surface 18 advantageously provides a long, stable flat area and for planing efficiency. The flat delta bottom surface 18 is substantially flat or horizontal, as best shown in FIG. 2, and may have a slight angle from either side of the centerline 16 of about ±5-10° from the horizontal, as best shown in FIG. 2A.
Angularly disposed left and right bottom portions 20 and 22 are attached to the respective left and right chines 12 and 14 and the bottom surface 18. The angular bottom portions 20 and 22 make an angle with the horizontal that ranges from approximately 25° degrees at section line E to about 39.9° at section line B.
The chines are wider and flat as they extend from section line A towards the transom at section line E. Together with the flat delta bottom surface 18, the flat chines between section lines C and E advantageously counteract the loss of stability at displacing speed or at rest. At the transom 6 at section line E, approximately 35-65% of the width of the hull is substantially horizontal or flat and may have ±5-10° variation from the horizontal, as best shown in FIGS. 2A and 2B. The chines advantageously flare outward in the forefoot area (between section lines A and C), displacing the water to the sides away from the boat, and then gradually flatten to horizontal at the transom 6 (section line E), as best shown in FIG. 2. The flare out advantageously sends water spray horizontally away from the hull. Additionally, the chines drop downwardly from the bow to the transom.
The flat hull surface in the stern area of the hull (between section lines C and E) advantageously provides the roll stability while the deep V and flare out chines in the landing area (between section lines A and C) advantageously provide a sharp entry where the boat breaks the water as it is propelled forward.
At the landing area, the hull provides a deep V profile that advantageously provides excellent entry through rough water at high speed with less slamming at high speeds. At the planing area, the wide flat chines and the flat delta bottom surface advantageously counteract the loss of stability at displacing speeds (lower speeds). The flat planing areas aft lead to good speeds and low fuel consumption. The low average deadrise aft provides very stable roll characteristics at slow speed and at rest.
The present invention can be used for boats with lengths of 12-50 ft. and all speeds from trolling to high speed planing.
While this invention has been described as having preferred design, it is understood that it is capable of further modification, uses and/or adaptations following in general the principle of the invention and including such departures from the present disclosure as come within known or customary practice in the art to which the invention pertains, and as may be applied to the essential features set forth, and fall within the scope of the invention or the limits of the appended claims.

Claims

1. A boat hull, comprising:

a) a transom and a bow;

b) left and right sidewalls extending from said transom and converging to meet at said bow;

c) a substantially flat delta bottom surface extending from said transom toward said bow;

d) left and right chines formed between said left sidewall and said bottom surface, and between said right sidewall and said bottom surface, respectively, said chines extending from said transom to said bow;

e) said flat delta bottom surface extending to about 75-80% of the length of said chines;

f) said chines and said bottom surface are substantially horizontal at said transom; and

g) said chines and said bottom surface comprise about 35-65% of the width of said hull at said transom.

2. A boat hull as in claim 1, and further comprising angularly disposed bottom portions joining said chines and said bottom surface.

3. A boat hull as in claim 2, wherein said bottom portions rise between about 25°-56° from a horizontal plane.

4. A boat hull as in claim 1, said chines are joined to said sidewalls.

5. A boat hull as in claim 1, wherein said chines flare up to direct water spray away from said hull.

6. A boat hull as in claim 1, wherein said flat delta bottom surface in cross-section has about ±5-10° angle from a horizontal on either side of a centerline through said boat hull.

7. A boat hull as in claim 1, wherein said chines and said bottom surface at said transom includes a variation from the horizontal of about ±5-10°.

8. A boat hull, comprising:

a) a transom and a bow;

b) a substantially flat delta bottom surface;

c) left and right sidewalls extending from said transom and converging to meet at said bow;

e) a planing area extending from said transom and a landing area extending from said bow;

f) said chines and said bottom surface are substantially flat in said planing area; and

g) angular bottom portions joining said chines and said bottom surface, said angular bottom portions having a deadrise increasing from said transom toward said bow.

9. A boat hull as in claim 8, wherein said chines flare up in said landing area.

10. A boat hull as in claim 8, wherein said landing area has a deep V cross-section.

11. A boat hull as in claim 9, wherein said chines and said bottom surface comprise about 35-65% of the width of said hull at said transom.

12. A boat hull as in claim 8, wherein said landing area is about 25%-50% of the chine length between said transom and said bow.

13. A boat hull as in claim 8, wherein said angular portions have a deadrise that increases from said transom toward said bow.

14. A boat hull as in claim 12, wherein said deadrise is from about 25° at said transom to about 56° near said bow.

15. A boat hull as in claim 8, wherein said flat delta bottom surface extends to about 75-80% of the length of said chines from said transom toward said bow, said bottom surface being wide to narrow toward said bow.

16. A boat hull as in claim 15, wherein said flat delta bottom surface in cross-section has about ±5-10° angle from a horizontal on either side of a centerline through said boat hull.

17. A boat hull as in claim 9, wherein said chines gradually widen and flatten as they extend from near said bow toward said transom.

18. A boat hull as in claim 8, wherein said chines drop in elevation from near said bow toward said transom.