U.S. patent application number 12/419973 was filed with the patent office on 2009-07-30 for fin stabilizer to reduce roll for boats in turns method and apparatus.
Invention is credited to Michael A. Baker, Richard M. Benson, William L. Hickok, Mark R. Morgan.
Application Number | 20090188416 12/419973 |
Document ID | / |
Family ID | 40897914 |
Filed Date | 2009-07-30 |
United States Patent
Application |
20090188416 |
Kind Code |
A1 |
Hickok; William L. ; et
al. |
July 30, 2009 |
FIN STABILIZER TO REDUCE ROLL FOR BOATS IN TURNS METHOD AND
APPARATUS
Abstract
The disclosure relates to a fin stabilization system adapted to
minimize roll about the longitudinal axis of the boat during sharp
cornering at very high speeds. In one form, equipment such as a
machine gun is mounted to the bow of the boat and targets are
adapted to be engaged in high-speed maneuvers when cornering and
the deck of the boat is not excessively rolled whereby blocking
visibility in a turn.
Inventors: |
Hickok; William L.;
(Bellingham, WA) ; Morgan; Mark R.; (Lynden,
WA) ; Benson; Richard M.; (Ferndale, WA) ;
Baker; Michael A.; (Burlington, WA) |
Correspondence
Address: |
HUGHES LAW FIRM, PLLC
5160 Industrial Place,#107
Ferndale
WA
98248-7819
US
|
Family ID: |
40897914 |
Appl. No.: |
12/419973 |
Filed: |
April 7, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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11684462 |
Mar 9, 2007 |
7513204 |
|
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12419973 |
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Current U.S.
Class: |
114/1 ; 114/126;
114/79W |
Current CPC
Class: |
B63B 3/44 20130101 |
Class at
Publication: |
114/1 ; 114/126;
114/79.W |
International
Class: |
B63B 39/06 20060101
B63B039/06; B63B 3/00 20060101 B63B003/00; B63G 1/00 20060101
B63G001/00 |
Claims
1. A fin stabilization system adapted to be mounted to the area of
influence of a boat which consists of the longitudinal rearward
laterally outward one-third section of the boat having a
longitudinal, lateral and vertical axis, the fin stabilization
system comprising: a. a first fin and a second fin positioned in
the area of influence of a boat having a rearward effective portion
and a forward effect of portion and a depth whereby the first and
second fins are parameterized where each are positioned to
according to the following ranges: i. a rear base distance from the
longitudinally rearward portion of the boat to the rearward
effective portion between the ranges of 5 in.-12 in., ii. having
the distance between the rearward effective portion and the forward
effective portion of no more than 70 in., iii. having a depth
component that is less than 6 in., b. whereby the fin stabilization
system is adapted to maintain the roll of the boat about the
longitudinal axis of no more than 20.degree. from a horizontal
plane in a turn in excess of speeds of 35 mph of the boat and the
radius of the turn is no more than 2.5 boat lengths.
2. The claim as recited in claim 1 whereby the first and second
fins are attached to a first and second mounting brackets each
having a base region and a mounting extension whereby the base
region is rigidly mounted to the lower surface of the lateral
portion of the hull and the first and second fins are mounted to
the mounting extensions of the first and second mounting brackets
respectively.
3. The fin stabilization system as recited in claim 2 whereby the
first and second fins are mounted to the mounting extensions of the
first and second mounting brackets respectively whereby the
mounting elements are flush with the surfaces of the first and
second fins.
4. The fin stabilization system as recited in claim 1 whereby the
roll of the boat is no more than 15.degree. in a turn in speeds in
excess of 35 mph.
5. The fin stabilization system as recited in claim 1 whereby the
roll of the boat is no more than 15.degree. in a turn in speeds in
excess of 40 mph.
6. The fin stabilization system as recited in claim 5 whereby the
longitudinal length of the boat is between 18 and 32 ft. whereby
the depth component of the first and second fins is less than 4.5
in.
7. The fin stabilization system as recited in claim 5 whereby the
turn diameter of the boat is no more than two boat lengths.
8. The fin stabilization system as recited in claim 6 whereby the
turn diameter of the boat is no more than two boat lengths.
9. The fin stabilization system as recited in claim 1 whereby the
hull of the boat is a planning hull.
10. The fin stabilization system as recited in claim 1 whereby the
boat comprises a metal multi-chambered perimeter hull portion
having two side hull portions which are on opposite sides of the
central hull portion, and which have forward perimeter hull
portions converging toward one another at a forward end portion of
the boat hull and said perimeter hull portion comprising: c. a
plurality of multi-creased wall sections, each of which has a
lengthwise axis, and each formed from a related metal sheet in a
surrounding wall configuration by being bent along a plurality of
generally lengthwise creases, with wall section portions extending
between adjacent pairs of said creases; d. said multi-creased wall
sections each having end perimeter edge portions with adjacent end
perimeter edge portions of adjacent multi-chambered wall sections
being adjacent to one another in end-to-end relationship at a
perimeter juncture location; e. a plurality of baffles, with each
baffle being positioned at a related perimeter juncture location,
with a perimeter edge of the baffle being adjacent to the end
perimeter edge portions of adjacent multi-chambered wall sections,
and with the adjacent end perimeter edge portions and the perimeter
edge of the adjacent baffle being welded together to form a
watertight seal, and with the adjacent baffle making an air seal
between interior regions of adjacent multi-chambered wall sections;
f. said multi-chambered wall sections and said baffles thus being
joined together to provide a plurality of airtight floatation
chambers, with each chamber being enclosed by a related wall
section and two related end baffles, with weld connections at the
related end baffles forming an airtight connection.
11. The fin stabilization system as recited in claim 1 whereby the
fin stabilization system is adapted to raise the laterally outward
fin in a turn out of the water and the laterally inward fin in a
turn is submerged in the water.
12. The fin stabilization system as recited in claim 11 whereby the
boat has an engine that is operatively attached to a propeller and
in a turn the propeller receives water with the lower concentration
of air than without the fin stabilization system.
13. The fin stabilization system as recited in claim 12 whereby the
roll about the longitudinal axis is less than 15.degree. at a speed
in excess of a 40 mi.-per-hour turn.
14. The fin stabilization system as recited in claim 12 whereby the
roll about the longitudinal axis is less than 10.degree. at a speed
in excess of a 45 mi.-per-hour turn.
15. The fin stabilization system as described in claim 16 whereby
the turn diameter is less than 2.5 boat lengths for a 270-degree
turn.
16. The fin stabilization system as described in claim 17 whereby
the turn is conducted where the engine is under full throttle for
the entirety of the turn.
17. The fin stabilization system as described in claim 1 whereby a
firearm is mounted to the bow of the boat.
18. The fin stabilization system as recited in claim 1 whereby the
boat is adapted to make a turn creating a G-force in the horizontal
direction that is in excess of 1.0.
19. The fin stabilization system as recited in claim 1 whereby the
boat is adapted to make a turn creating a G-force in the horizontal
direction that is in excess of 1.5.
20. The fin stabilization system as recited in claim 1 whereby the
boat is adapted to make a turn creating a G-force in the horizontal
direction that is in excess of 2.0.
21. The fin stabilization system as recited in claim 1 whereby the
boat is between 17 ft. and 35 ft. in longitudinal length.
22. The fin stabilization system as recited in claim 1 whereby the
boat length is between 20 ft. and 32 ft. and longitudinal
length.
23. A fin stabilization system adapted to be mounted to the area of
influence of a boat which consists on the longitudinal rearward
laterally outward one-third section of the boat having a
longitudinal, lateral and a vertical axis, the fin stabilization
system comprising: a. a first fin and the second fin positioned in
the area of influence of a boat having a rearward effective portion
and a forward effect of portion and a depth whereby the first and
second fins are parameterized where each are positioned to
according to the following ranges, i. a rear base distance from the
longitudinally rearward portion of the boat to the rearward
effective portion between the ranges of 5 in.-12 in., ii. having
the distance between the forward effective portion positioned in
the area of influence of the boat, iii. having a depth component
that is less than 6 in., b. whereby the fin stabilization system is
adapted to maintain the roll of the boat about the longitudinal
axis of no more than 20.degree. from a horizontal plane in a turn
in excess of speeds of 35 mph of the boat at a turn radius of more
less than 2.5 boat lengths.
24. A boat hull comprising: a. a central hull portion; b. a metal
multi-chambered perimeter hull portion having two side hull
portions which are on opposite sides of the central hull portion,
and which have forward perimeter hull portions converging toward
one another at a forward end portion of the boat hull; c. said
perimeter hull portion comprising: i. a plurality of multi-creased
wall sections, each of which has a lengthwise axis, and each formed
from a related metal sheet in a surrounding wall configuration by
being bent along a plurality of generally lengthwise creases, with
wall section portions extending between adjacent pairs of said
creases; ii. said multi-creased wall sections each having end
perimeter edge portions with adjacent end perimeter edge portions
of adjacent multi-chambered wall sections being adjacent to one
another in end-to-end relationship at a perimeter juncture
location; iii. a plurality of baffles, with each baffle being
positioned at a related perimeter juncture location, with a
perimeter edge of the baffle being adjacent to the end perimeter
edge portions of adjacent multi-chambered wall sections, and with
the adjacent end perimeter edge portions and the perimeter edge of
the adjacent baffle being welded together to form a watertight
seal, and with the adjacent baffle making an air seal between
interior regions of adjacent multi-chambered wall sections; iv.
said multi-chambered wall sections and said baffles thus being
joined together to provide a plurality of airtight floatation
chambers, with each chamber being enclosed by a related wall
section and two related end baffles, with weld connections at the
related end baffles forming an airtight connection. v. a fin
stabilization system having a first fin and a second fin positioned
in an area of influence of a boat having a rearward effective
portion and a forward effect of portion and a depth whereby the
first and second fin is our parameterized where each are positioned
to according to the following ranges, a rear base distance from the
longitudinally rearward portion of the boat to the rearward
effective portion between the ranges of 5in.-12 in., having the
distance between the forward effect of portion positioned in the
area of influence of the boat, having a depth component that is
less than 6 in., vi. whereby the fin stabilization system is
adapted to maintain the roll of the boat about the longitudinal
axis of no more than 20.degree. from a horizontal plane in a turn
in excess of speeds of 35 mph of the boat at a turn radius of less
than 2.5 boat lengths for turn at or greater of 90 degrees.
25. A method of stabilizing a boat in a turn comprising the steps
of: a. retrieving a boat having a longitudinal length between 17
ft. and 35 ft. having a longitudinal and lateral axis b.
maintaining the roll of the boat about the longitudinal axis during
a high-speed turn that is no more than 200 with respect to the
horizontal plane at speeds in excess of 35 mph and a turn of less
than three boat lengths, the boat having an engine which produces a
maximum horsepower, c. attaching a fin stabilization system to the
area of influence of a boat which consists on the longitudinal
rearward laterally outward one-third section of the boat having a
longitudinal, lateral and a vertical axis, the fin stabilization
system comprising a first fin and the second fin positioned in the
area of influence of a boat having a rearward effective portion and
a forward effective portion and a depth component, d. positioning a
rear base distance from the longitudinally rearward portion of the
boat to the rearward effective portion between the ranges of 5
in.-12 in., e. positioning the forward effective portion positioned
in the area of influence of the boat, f. providing the depth
component that is less than 6 in. g. adjusting the dimensions of
the first and second fin where the forward effective portion is
positioned longitudinally more forward in a longer boat and it is
positioned longitudinally more rearward in a shorter boat, and h.
decreasing the depth of the first and second fins as the designed
maximum horsepower of the boat is increased and increasing the
depth of the first and second fins as the designed maximum
horsepower of the boat is decreased.
26. The method as recited in claim 25 whereas the method for
adjusting allows for stabilization of the boat to minimize the
longitudinal roll of the boat about the longitudinal axis and allow
a lower percentage of aerated water to pass through the propeller
of the boat.
27. The method as recited in claim 25whereas when the designed
gross weight of the boat increases the depth of the first and
second fins increases and when the designed gross weight of the
boat decreases the depth value for the first and second fins
decreases.
28. The method as recited in claim 26 where as the designed gross
weight of the boat increases, the lower range value of the distance
between the rearward effective portion and the forward effective
portion of the first and second fins increases.
Description
RELATED APPLICATIONS
[0001] This application is a continuation of U.S. Ser. No.
11/684,462 filed Mar. 9, 2007, and claims priority benefit of U.S.
Ser. No. 60/452,710, filed Mar. 7, 2003 and U.S. Ser. No.
10/796,472 filed Mar. 8, 2004.
BACKGROUND OF THE INVENTION
[0002] a) Field of the Invention
[0003] The present invention relates to stabilizing systems for
boats, and more particularly for a stabilizing system which better
enables boats to make sharp turns, and particularly sharp turns at
relatively high speeds where the roll of the boat (rotation about
the longitudinal axis of the boat) is minimized.
[0004] b) Background Art
[0005] When some boats having a shallow draft are making relatively
sharp turns at high speeds, instability can be a problem. In some
instances and with some configuration of boats (if not many
configurations), when the rudder or the motor is turned as to
execute a sharp turn, the boat will lean into the curve/roll, with
the side of the boat on the inside of the curve moving downwardly
into the water, and the opposite side on the outside of the boat
being raised upwardly from the water. In this situation, it
sometimes happens that the rear portion of the boat will slide or
"skip" laterally, and then may tend to right itself with the boat
tilting back the other way with the other side portion of the boat
being lowered into the water. Not only does this create undesired
instability, but it also does not permit proper execution of the
sharp turn. The present invention is designed to alleviate that
problem.
[0006] By way of pertinent background previous prior art design
such as that known in U.S. Pat. No. 6,520,107, the boat a tendency
to "heel over" whereby the boat rotates about its longitudinal axis
into the direction of the turn. This is undesirable in a situation
where the boat is desired to remain in a substantially planar
position about the longitudinal axis and in a situation such as
where a firearm is mounted in the bow portion of the watercraft
where the term, "guns on target" is necessary to complete combat
operations and maneuvers. For the disclosure of the present
invention is well adapted to keep the boat flatter and less
rotation about the longitudinal axis of the boat (roll) in the
course of a turn, particularly where high lateral accelerations are
exerted on the boat.
[0007] One prior art method of lifting the stern portion of the
boat is to use trim tabs which are essentially vertically downward
extending surfaces that extend into the water and provide a
vertical lift in the aft portion of the boat to level it out. These
are hydraulic trim tabs that are always placed on the stem of the
boat. It has been found that the trim tabs are inadequate to
prevent rotation about the longitudinal axis of the vessel in
particularly in high G and sharp turns which is necessary in
certain maneuvers such as military maneuvers. Trim tabs have been
wholly inadequate to maintain a roll which is here in defined as
rotation about the longitudinal axis of the boat.
[0008] Other known prior art includes U.S. Pat. No. 5,611,295
(Stables) where in the introductory portion of the patent (column
1), there is discussed the problem of "spin out" which is indicated
as a problem of personal watercraft due to their more forward
center of gravity. There is provided on each rear side portion of
the boat a pair of inner and outer plates 10 and 11, each outer
plate 10 having a length which can vary from eighteen to thirty
inches. In column 2, line 34, it is indicated that the outer plate
10 will extend below the bottom edge of the hull 15 by
approximately one inch, but it is indicated that the device is not
necessarily limited to that dimension.
[0009] The operation of this apparatus is discussed on column 3,
beginning on line 21. It is pointed out (beginning on line 28) that
a unique feature of the outer plate 10 is its shape, and it is
stated that this eliminates a detrimental reaction known as
"sticking" in the aircraft industry. Beginning on line 34, it
indicates that as the outer plate 10 moves laterally while in the
turn, if it were perfectly rectangular, a low pressure area down
the center of the plate would form, and thus the lower pressure
area would create a suction that would stick the plate to the
water. Then, when the boat is coming out of the turn and returning
to a straight course, the craft must be over-steered to break the
plate loose. This results in a brief period of loss of control. The
patent indicates that the sides of the outer plate 10 are not
parallel, and this discourages the "alignment" of any fluid
circulation and reduces the formation of the pressure area. It can
be seen in viewing FIGS. 1 and 4, that the upper and lower surfaces
and the front and rear surfaces are non-parallel with one
another.
[0010] Also in FIG. 5, the outer plate is positioned at the side of
the boat and is aligned so that in a frontal view this plate slants
downwardly and slightly inwardly toward the center of the boat.
Thus, it would appear that as one side of the boat dips into the
water making a sharp turn, this slant off the vertical would become
more pronounced.
[0011] Additional patents show various sorts of plates or
stabilizers that are mounted to the boat so as to protrude into the
water.
[0012] U.S. Pat. No. 6,546,884 131 (Rodriquez) shows a "jet
propelled watercraft stabilizing system." This shows what appear to
be shaped more like fins that one would see commonly on a fish,
with these fins protruding outward and downwardly from the rear
side of the boat. In reading the patent, it would appear that the
person steers the boat in large part by leaning to one side or the
other and causing the fin to dip into the water. The angular
position of the fins is adjustable and trim blocks are provided to
accomplish the positioning of the fins at different angles.
[0013] U.S. Pat. No. 6,546,888 B2 (Bertrand et al.) shows
stabilizing fins which are removably secured to either side of the
small watercraft. FIG. 6 gives a rear view of the stabilizing fin,
and it would appear to have more of an appearance of a right angle
triangle with the hypotenuse of the triangle having a curve and one
side of the triangle attaching to the boat.
[0014] U.S. Pat. No. 6,325,009 B1 (Schulz et al.) shows a sailboat
having a dagger board that can be retracted or extended downwardly
into the water on opposite sides of the boat to control side slip
or leeway.
[0015] U.S. Pat. No. 5,273,472 (Skedeleski et al.) shows a flexible
fin applied to the edges of a surf board for added stability.
[0016] U.S. Pat. No. 4,561,371 (Kelley et al.) shows a catamaran
stabilizing structure where there is a stabilizing dagger board on
each hull. The center board has a double-wing stabilizer with
adjustable pitch.
[0017] U.S. Pat. No. 3,473,502 (Wittkamp) shows a pontoon boat with
pontoons on opposite sides in something of a catamaran structure
where there are keel-like elements, such as shown at 38, and one
end of which is secured to the pontoon.
[0018] By way of general background it should be noted that when
the boat is chinning the propeller portion of the motor is hitting
"bad" or aerated water where the propellers are no longer in the
higher viscous regions of regular water but in pure air or in air
water mixture which has a lower density and lower counter force on
the propeller causing an increase in the rpm's of the propellers.
For example, when a propeller (or one of two propellers in a dual
motor boat) is outside the water, it can reach very high rpm's
(e.g. 6,000 rpm's). When this high velocity rotation reenters the
water the momentum of the propeller as well as the applied torque
from the motor can cause an abrupt acceleration thereby injuring
the driver and passengers of the boat (such as breaking their
tailbone and ribs). This is referred to as "chinwalking". Therefore
it is advantageous to have the boat maintain a substantially
minimal roll during a relatively sharp high-speed corner. In an
environment such as a personal watercraft (i.e. a jet ski) this is
not an issue because such watercraft are propelled by a jet
propulsion hydraulic system, not a propeller which is most commonly
used in a propeller driven system.
[0019] It should be noted that in the normal operations of boats,
when engaging in a turn there is a de-acceleration and an excessive
roll. For terms of definition, a certain degree of roll (i.e. 7-20
degrees) which in normal boating craft is sufficient and in some
cases desirable because the net thrust with the lateral centrifugal
force in gravity is substantially in line with the planar surfaces
of the boat such as seats and standing areas. However, in recent
times where certain combat operations necessitate a substantially
lower amount of roll during turns, this excessive roll (i.e. 7-20
degrees with regard to the horizontal plane) is undesirable.
Therefore even in prior art controlled turns where the velocity is
lowered and the amount of roll is such that it exceeds 20 degrees,
in a military or law enforcement type operation this is
undesirable. It has been found in recent times that maintaining the
roll of the boat to a minimum (e.g. 20-5 degrees), a gunner at the
bow of the boat can maintain "guns on target" and engage a
potential threat on the sea or the body of water. Further, it has
been found that these turns can be engaged at full throttle and at
full speed (e.g. 50 mph and at least 35-40 mph) where the roll of
the boat is minimized and a wash out does not occur. The phenomena
and apparatus to accomplish these goals are discussed further
herein.
[0020] It should be noted that the term "guns on target" is in
reference to maintaining a bead on a target during operational
maneuvers. One of these maneuvers comprise high speed turns to port
and starboard directions. For example, the vessel with a 50-caliber
machine gun mounted in the bow is making a port turn (i.e. to the
left). In a prior art watercraft, the watercraft vessel will rotate
into the turn where the starboard lateral portion will raise up
with respect to the water thereby blocking visibility off the
starboard bow and starboard side in general. This is clearly
unacceptable if a potential target is located in this area. In many
types of operations where such a turn is conducted, the driver may
be avoiding a collision with a potential target whereby maintaining
visibility and the ability to maintain a site picture is of a
highest requirement.
[0021] It should further be noted that an excessive chinning or
chine walking where the roll of the boat is so excessive that the
propellers intermittedly engage causing intermittent thrust it is
extremely undesirable in operations to have because this induces a
lack of control where the boat is unstable and unsafe potentially
causing injury to the driver and passengers. It should be noted
that chinning is a roll where the boat rotates inwardly toward the
turn. Chinning occurs where the boat rotates at the longitudinal
axis inwardly in the direction of a turn and can have catastrophic
effects where in some cases a boat will rotate and snap back to the
opposite direction (where the outer lateral portion of the boat
violently snaps downwardly) and cause bodily injury to the
passengers and driver of the boat. Further, chinning or chine
walking can compromise the boaters' abilities to engage in their
missions such as firing a heavy machine gun, "bumping a boat" or
maintaining a high speed pursuit.
[0022] It should be further noted that another benefit by implying
the fin system is the vessel will track better at a lower velocity
with respect to the water where the aft portion of the boat will
not swing around or drift in a turn when subjected to the
centrifugal forces of the turn. Therefore, essentially the vessel
will go where it is intended without drifting in a low speed
tracking where the rearward portion of the boat kicks outwardly
away from the direction of the turn.
[0023] Therefore, it is a goal to stabilize the boat in corners to
prevent chinning and roll in the course of a high G-force turn
under full throttle in extreme maneuvers.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] FIG. 1 is a side elevational view of a boat incorporating
the stabilizing system of the present invention;
[0025] FIG. 2 is a view similar to FIG. 1, but drawn to an enlarged
scale and looking only at the rear of the boat, to show one of the
turn control elements in more detail;
[0026] FIG. 3 is a sectional view taken along line 3-3 of FIG. 1,
showing the turn control element attached to the lower starboard
side of the boat;
[0027] FIG. 4 is a top plan view showing the motor at the stern of
the boat turned so as to turn the boat to the right; and
[0028] FIG. 5 is a schematic rear elevational view of the boat,
drawn somewhat schematically and showing the boat executing a turn
to the right, and also illustrating the operation of the present
invention;
[0029] FIG. 5a shows a side elevation 12 of an example of
implementing the apparatus of the present invention where a device
such as a machine gun is mounted to the bow of the boat;
[0030] FIG. 6 shows a qualitative graph showing general adjustments
of the distance parameter of the fins with respect to various
environment variables;
[0031] FIG. 7 shows a three-dimensional graph for the upper
perimeter distance variable for the "B" dimension with respects to
Power and Gross Weight for a 25 ft. boat;
[0032] FIG. 8 shows a three-dimensional graph for the lower
perimeter distance variable for the "B" dimension with respects to
Power and Gross Weight for a 25 ft. boat;
[0033] FIG. 9 shows a three-dimensional graph for the upper
perimeter distance variable for the "B" dimension with respects to
Power and Gross Weight for a 35 ft. boat;
[0034] FIG. 10 shows a three-dimensional graph for the lower
perimeter distance variable for the "B" dimension with respects to
Power and Gross Weight for a 35 ft. boat;
[0035] FIG. 11 shows a three-dimensional graph for the upper
perimeter distance variable for the "D" dimension with respects to
Power and Gross Weight for a 25 ft. boat;
[0036] FIG. 12 shows a three-dimensional graph for the upper
perimeter distance variable for the "D" dimension with respects to
Power and Gross Weight for a 25 ft. boat;
[0037] FIG. 13 shows a three-dimensional graph for the upper
perimeter distance variable for the T" dimension with respects to
Power and Gross Weight for a 35 ft. boat;
[0038] FIG. 14 shows a three-dimensional graph for the lower
perimeter distance variable for the "D" dimension with respects to
Power and Gross Weight for a 35 ft. boat.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0039] As an introductory comment, the present invention is
particularly adapted for use in a boat such as shown and described
in the recently issued patent, U.S. Pat. No. 6,520,107 B1, with the
inventor being one of the inventors as in the present application.
The entire text and drawings of U.S. Pat. No. 6,520,107 B1 are
hereby incorporated by reference.
[0040] The boat 10 comprises a hull 12 having front and rear end
portions 14 and 16, sidewalls 18, and a bottom wall 20. As can be
seen in FIG. 5, in this particular configuration the bottom wall 20
is V-shaped so as to have a center keel 22 and two bottom wall
sections 24 slanting upwardly and laterally outward at a moderate
angle from the keel 22 at a moderate angle relative to the
horizontal.
[0041] As is disclosed more completely in U.S. Pat. No. 6,520,107
131, the sidewall portions 18 are in this configuration made of
aluminum sheets which have in cross-section a multi-creased
configuration comprising planar portions 26 which connect to one
another at creased locations 28. Thus, it can be seen in FIG. 6,
that there is an outside substantially vertically aligned sidewall
portion 30 which is connected at its lower end to a lower sidewall
portion 32 which slants downwardly and inwardly at an angle of a
little bit less than 45.degree. to the horizontal, with this being
in turn connected to a yet lower side wall portion 34 having a
laterally outward creased connecting location 36 and an inner
creased location 38.
[0042] The boat 10 which has been described thus far is, or may be,
the same as shown in U.S. Pat. No. 6,520,107 131. The newly added
features of the present invention will now be described, as these
are used in connection with the boat described immediately above,
with the understanding that these could also be used with other
boat designs.
[0043] To aid the description of the boat an axis system is defined
where as shown in FIG. 1, the axis indicated at 5 shows a
longitudinal forward direction and the axis indicated at 7
indicates a vertical direction. Further, as shown in FIG. 3 the
axis indicated at 9 indicates a lateral direction. The boat 10
comprises a longitudinally rearward portion 11 which is defined as
the end portion of the boat which is normally a region where the
substantially horizontal surface of the hull transitions to a
vertical surface which eventually extends out of the water.
[0044] There is installed a fin stabilization system 21 at the rear
end of the boat that comprises right and left oppositely positioned
fins or otherwise referred to as turn control elements 40 and 42
connected to the lower rear outer portions of the hull 12. Each
turn control element 40 and 42 is in the form of a flat plate
having a planar configuration. Each turn control element 40 and 42
has a downwardly and rearwardly sloping front edge 44, an elongate
lower edge 46, and a rear edge 48 which is shown herein as nearly
vertical but having a moderate upward and rearward slant. In this
preferred embodiment, the total length dimension of each of the
turn control elements 40 and 42 is indicated at B in FIG. 2, and is
approximately four and one-half feet; however the dimension are
further discussed herein. The vertical dimension of each element 40
and 42 is indicated at D, and is approximately one-half foot.
Further, the dimension A. as shown in FIG. 2 is defined as the
distance between the rear effective portion of the fins 40 and 42
and the longitudinally rearward portion 11 of the boat. It has been
found that having this gapped region is advantageous to preventing
aerated water from passing to the propeller of the boat during a
high-speed turn. It should be noted that for purposes of this
document, the rate of speed that is indicated for a turn is hereby
defined as the rate for entering into a turn and for purposes of
claim limitation, the rates for the speeds do not need to be
maintained throughout the turn. In other words, a 35 mph turn is
expressly defined as entering into the turn and 35 mph with the
throttle on and the rate of this speed need not be maintained
throughout the course of the turn but rather. As shown in FIG. 3,
the dimension E is provided which measures the approximate lateral
distance from the fins 40 and 42 from the center line of the boat.
However, it is obvious that these dimensions could be changed
depending on various factors described below, such as the size of
the boat, the design of the boat, performance characteristics of
the boat, adaptability to various boat configurations, and other
factors.
[0045] As shown in FIG. 3, each of the turn control elements (i.e.
first and second fins) 40 and 42 can be connected by suitable
mechanical means, such as a right-angle bracket 54, which are
connected at various bolt hole locations, as indicated at 56 in
FIG. 2.
[0046] The bracket 54 comprises a base region 55 and an extension
57. In one form, the base region 55 is rigidly connected to the
sidewall portion 34 by, for example, being welded thereto. The
connectors 59 in one form are a nut and bolt arrangement. Although
as shown in FIG. 3, the nuts and bolts extend laterally outside of
the surfaces of the extension 57 and the fin 40, in one form either
or both of the end sections of the connectors 59 are flush with the
adjacent surfaces. This can be accomplished with recessed regions
in the fin 40 and extension 57.
[0047] In this particular configuration, it can be seen that the
alignment of the plane occupied by each of the turn control
elements 40 and 42 is substantially perpendicular to its related
adjacent bottom wall section 24. Thus, each of the turn control
elements 40 and 42 have a downward and outward slant.
[0048] As shown in FIG. 2, the first and second fins 40 and 42
collectively comprise a fin stabilization system. The first and
second fins 40 and 42 each comprise a rear effective portion 49 and
a forward effective portion 51. These effective portions are
defined as longitudinal regions where the first and second fin
substantially begin and end. Other words, for purposes of
describing the first and second fins 40 and 42, the effective
portions relate to approximate distances where the vertical
dimension is substantially such as to have a sufficient
hydrodynamic influence on the boat. For example, the vertically
higher forward portion of the fins 40 and 42 could theoretically
extend the lengthwise portion of the boat but be at a sufficiently
low depth (e.g. less than 3/8 of an inch) to have any significant
effect upon the turning characteristics of the boat. Therefore this
thin depth portion would not be considered a part of the effective
portions of the first and second fins 40 and 42. It should be noted
that the distances A, B, and D are measured from the longitudinally
rearward portion 11 of the boat, and the rearward and forward
effective portions of the fins 40 and 42.
[0049] To describe now the operation of the present invention,
reference is made to FIGS. 4 and 5. It can be seen in FIG. 4 that
there is a motor 58 (either an outboard motor or inboard/outboard
motor) mounted to the stern of the boat, and in the orientation of
FIG. 4, the rear end of the motor is slanted starboard (to the
right) so as to execute a turn to the right. In executing this
turn, the starboard side of the boat will tilt downwardly, as seen
in FIG. 5, as the boat moves into the turn. When this occurs, it
can be seen that the port side of the boat 10 lifts upwardly, and
in this particular drawing of FIG. 5 actually moves out of the
water. It should be noted that in one form two motors are employed
and attached to the rearward portion of the boat. In this
embodiment maintaining a substantially more level boat during a
high-speed turn is desirable because each of the props are
positioned in the greater laterally outward location. In this
location the props are more susceptible to being exposed to aerated
water as the laterally outward region of the boat raises.
[0050] Now, let us assume that the turn control elements 40 and 42
are not mounted to the boat. In this instance, when the boat 10 is
going into the turn and in particular executing a rather sharp
turn, as indicated earlier, there is a tendency for the rear end of
the boat to "skip" out of the water. It can be surmised, by viewing
FIG. 5, that this is due at least in part to the slanted left
bottom wall section 24 slipping sideways and creating an upward
force component tending to lift the rear of the boat up from the
water, and the centrifugal force causing it to skip.
[0051] However, with the turn control elements 40 and 42 being
installed, it can be seen that the right element 40 is positioned
in the water, and this resists this lateral skipping of the rear
end portion of the boat 10. With this side slippage of the rear end
of the boat being in large part prevented, there is less lateral
movement of the rear of the boat to the left, and the effective
upward force exerted on the left bottom wall section 24 is
substantially reduced. Thus, the combination of these applied
forces enables the boat to make a much tighter turn and avoid the
boat becoming unstable in the manner described above with respect
to the prior art.
[0052] It is believed that the above explanation is at least a
partial explanation of the various phenomena involved. However,
there may be other factors which contribute to the performance
advantages obtained by the present invention, and regardless of the
accuracy of the explanation given above in this text, it has been
found by actual experimental use that these turn control elements
40 and 42 do contribute to the performance of the boat 10 in making
relatively sharp turns at high speed.
[0053] As shown in FIG. 5a located in the bow region of the boat
there is a mounted firearm 50 which in one form is a 50 caliber BMG
machine gun. Of course other types of firearms and equipment can be
mounted thereto. As further shown in FIG. 5a, a control center 52
is provided. A control center 52 has the effective shifting the
center of gravity of the boat forward.
[0054] It is important to note that without maintaining a minimum
roll of the boat about the longitudinal axis during a high-speed
turn (less than 20.degree. roll with respect to the horizontal
plane, less than 15.degree. in any preferred form and less than
10.degree. in a most preferred form). These turns can occur
anywhere between 3-60 mph. In one range, these turns occur between
45 and 55 mph. One form of turning the boat is maintaining a full
throttle at a high-speed. The turn diameter of the boat is
approximately no more than three boat lengths in one form is less
than 21/2 boat lengths. In a most preferred embodiment the turn
diameter is less than two boat lengths. It is desirable to maintain
a minimum roll in order to operate the equipment on the boat that
is necessary to maintain visual contact on the side of the boat
with the lateral portion that is raised vertically in a turn. Of
course the lateral G-forces with such a sharp fast turn can be very
high. It has been estimated that the lateral G-forces has or can
exceed two Gs in the lateral direction. In a broader scope, the
lateral G's exceed 1-1.5 G's in the lateral direction during a
high-speed turn. It should be noted that because the boat remains
substantially flat during these high-speed turns, it is advisable
that the passengers and the driver are buckled down in some form.
Prior art boats tend to excessively roll
(roll>20.degree.-15.degree. with respect to the horizontal plane
in a high-speed turn) which in many environments is a desirable
feature because the net thrust combining the vertical force of
gravity and the lateral centrifugal force produced by the
acceleration of the turn is at a downward and outward angle from
the center of curvature of the turn. Therefore, having an excessive
roll is desirable because the fixtures of the boat such as the
seats and flooring are substantially perpendicular to the net
thrust. In other words, the passengers and drivers merely feel more
force upon the seats and flooring but not a lateral force with
respect to the boat that knocks them off-balance and in some cases
throws them clean off the boat.
[0055] As shown in FIG. 6 there is a table where the environment
that the fin is placed in is shown with respect to various
dimensions of the fin that extend vertically downwardly along the
negative Y-axis. With the first column entitled "Length", there is
shown the result of general hypothesis of altering the various
dimensions in a qualitative manner. The dimension "A" in one form
may increase with respect to a longer boat; however, it has been
found that maintaining it at constant distance would be between
3-12 and more preferably between 4 to 10 inches, in a more
preferred form between 5 to 9 inches. This dimension is from the
rear-most portion of the transom the longitudinally rearward
portion 11 to the upper most aft portion of the fin at the rearward
effective portion 49. With respect to the second column entitled,
"Weight", most of the parameters will remain constant whether
lowering or increasing the weight with exception to the depth V
would slightly increase with respect to a greater weight imparted
upon the vessel. Now looking at the third column where the center
of gravity is shown with respect to the fin parameters, as the
center of gravity is aft (rearward) the dimension A may stay the
same or decrease slightly. Further, as the center of gravity is
positioned aft the dimension B will increase in the overall length
of the fin.
[0056] Further as the center of gravity goes aft, the `D` or depth
of the fin will decrease. On the converse, as the center of gravity
goes forward, the dimension `D` will increase and extend deeper
into the water. It is theorized that having this deeper insertion
in the water is necessary to grab more water during maneuvers where
it would be necessary to have a greater dimension.
[0057] With respect to speed, if the speed increases it is
theorized that parameter A would increase thereby creating a larger
gap region in the aft region of the boat. Further, it is theorized
in this increase of speed that the overall length B would decrease
and the depth of the fin D would decrease as well. When there is a
high rate of speed of the boat with respect to the water, it is
thought that less lift is required whereby the above-mentioned
dimensions will affect accordingly the amount of lift.
[0058] Now referring to the fifth column referred to as the horse
power of the vessel, it should first noted as a preliminary matter
that in general when horse power increases there is cross over
effect of the previous three parameters whereby the speed will have
a tendency to increase in corners, the center of gravity will shift
aft and the weight will increase. As shown in FIG. 6, there tends
to be a canceling effect to some degree where the speed increases
which causes A to increase and the center of gravity is aft which
has a tendency for A to decrease, there is a quasi canceling effect
whereby increase in the horse will remain a substantially constant
dimension A. This is similar for dimension B with a like type of
canceling effect. However, it has been found with respect to
dimension D, as the horsepower goes up, the net effect is having a
smaller value D. This has essentially "two for, one against" effect
where the speed increase will have a tendency to decrease the
parameter D and with an aft center gravity will decrease the value
D. However, an increase of net weight will have a slight tendency
to increase the value of D but the net effect is to decrease the
dimension D as horse power increases.
[0059] With respect to the turning radius, this is further a
function of the horsepower of the boat to some extent. However,
usually a tighter training radius is a desired result of the
watercraft and the fin system. In general to obtain a tighter turn
with higher horsepower the parameter A is increased which has been
found to have a tendency to reduce the amount of aerated water
entering the propeller. Further, it has been found that shortening
the dimension B has an advantageous effect as well. Finally,
decreasing the depth D of the fin has an effect of aiding and
reducing the turning radius. It should be reiterated that the tight
turning radius is generally a desired goal of the watercraft. This
is generally a function of the horsepower of the watercraft. On the
right hand portion of FIG. 6, it is theorized that with sponsons
positioned on a lateral portion of the boat there is a tendency to
have greater lift which would increase the length of D. Further,
for result of having bad water, if there is less bad water which is
a good condition the parameter A is generally increased to
accommodate this. For example, if there is a problem with having
bad water entering the props increasing the parameter of A would
generally assist in preventing "bad" water or aerated water.
Further, if bad water is occurring, parameter D would decrease
thereby assisting the creation of good water which is fed to the
props. It should be noted that all these qualitative factors of
increasing and decreasing are generally reactive to an existing
type based design where adjusting various the parameter is executed
to create a good boat that has a proper flat tracking roll about
corners.
[0060] It is theorized that the extensions need the support of the
hull to maintain rigidity because of the extreme force placed on
the fins. It should be noted that an area of influence which is
defined as the rearward 1/3 longitudinal distance of the boat is a
desired location of the extension. Therefore, the forward most and
rearward longitudinal most portion of the fin will be positioned
within this 1/3 area in the aft portion of the boat. Therefore, an
effective area of the fin is defined as a substantial length D
value which engages the fluid for desired turning effects of
maintaining a flat track. It should be noted that the depth value D
and the length B help define the effective area of the fin. The
effective area is defined as a substantial surface area to engage
water for the hydrodynamic effects to induce flat tracking (i.e.
longitudinal rate<20 degrees into broad scope or <15 degrees
in a preferred scope and <10 degrees in the most preferred
form). Of course it is obvious that various embodiments could
slightly deviate at various longitudinal positions to be outside
the ranges described below. However, where the effective area is
substantially within the ranges described below is here in covered
as and defined as the effective area. In essence, the position of
the fin is within about the 1/3 longitudinal location of the boat
in the aft portion. It should be noted that another way of
parameterizing the results that a deep fin causes as well as a flat
track which is generally between 5 to 20 degrees in a broad range
with a respectable amount of lateral G force such as 0.5-2.5
lateral G's. Further the amount of G's the fin system allows to
produce is anywhere between as mentioned 0.5-2.6 Gs laterally. When
the boat is remained substantially flat about the longitudinal axis
with the high G's there is an extreme amount of acceleration felt
upon the passengers and driver. Therefore, as mentioned above, it
is advised that the passengers and driver are buckled into the
vessel in some sort. The lower horsepower you would need the depth
of D with a fin because the boat isn't lifting on plane as high so
the influence must be deeper. With the high horse power such as
500-horsepower, a three inch would be an estimated maximum because
the hook would be too great.
[0061] Now referring to FIGS. 7-14, it is generally shown ranges of
dimensions that has been found and are theorized to provide
desirable results of flat tracking during high-speed cornering. In
general, each of the combinations of FIGS. 7-8, 9-10, 11-12, and
13-14 disclose upper and lower ranges for various parameters at
different boat lengths. In general the vertical axis in the graphs
shown in FIGS. 7-14 indicates the ranges of the dimensions in
inches. The laterally extending axis indicates various gross
weights of the boat's where the fins stabilization system is
applied thereon. The depth axis sliding off at an angle indicates
the horsepower of thrust of the boat's engine. As described above,
in general there is a spillover effect of the horsepower and other
parameters such as weight, position of the center of gravity in the
longitudinal direction and speed. Therefore for simplicity in
showing the arrangement of relationships for the dimensions of the
fin control system 21 with respect to the parameters of the boat
and performance, horsepower is shown to generally indicate the
dimension/parameter relationships.
[0062] Referring to FIGS. 7-8, there is shown parameter values for
the dimension "B" that is shown in FIG. 2. FIGS. 7 and 8 relate to
parameter value B for a 25 ft. boat. FIG. 7 indicates an upper
range 70 that is hypothesized or tested empirically for an upper
range of an overall length of the fins 40 and 42. It should be
noted that a lower horsepower boat (e.g. 300 horsepower) tends to
increase the length of the fins 40 and 42. It should be noted that
the values in the graphs as shown in FIG. 7 are general estimates;
however, it is further theorized that having values of "A" and "B"
that in combination position the fin control system 21 and the
rearward one third portion of the boat would function properly in
the broader scope of the disclosure.
TABLE-US-00001 Weight 3.5k 10k 15k Horsepower 300 60'' 60'' 60''
400 54'' 54'' 54'' 500 54'' 54'' 54''
[0063] FIG. 8 shows the lower ranges indicated at 72 that are
theorized and found empirically to give proper results for the fin
control system attached to a boat. It can be seen in the left-hand
portion of FIG. 8 that a high horsepower low weight boat can have a
lower minimum value (be shorter) than a heavy little horsepower
boat which would require a relatively higher minimum value. FIG. 8
further discloses that in general, decreasing the horsepower of the
boat tends to have a larger minimum value for the parameter B.
Further, looking at the gross weight in isolation indicates that
increasing the gross weight tends to increase the minimum workable
value of the parameter B for desired results. The data for the
values as shown in FIG. 8 are shown below.
TABLE-US-00002 Weight 3.5k 10k 15k Horsepower 300 40'' 44'' 48''
400 36'' 47'' 48'' 500 32'' 40'' 44''
[0064] Now referring to FIG. 9-10, there is shown parameter values
for the "B" parameter for 36 ft. boat. FIG. 9 shows the upper range
value in FIG. 10 shows a lower range value based upon empirical and
theoretical analysis.
[0065] As shown in FIG. 9, the longitudinal length "B" of the fins
40 and 42 generally tend to increase in maximum desired length as
the horsepower decreases as shown by the graph surface 74. It has
been found that with a higher horsepower boat the high-speed turns
generally are faster whereby the reaction forces by the water is
greater and a relatively shorter fin is only required to prevent
excessive roll and promote flat tracking. The FIG. 9 data is listed
below as:
TABLE-US-00003 Weight 3.5k 10k 15k Horsepower 300 80'' 80'' 80''
400 54'' 54'' 70'' 500 54'' 56'' 60''
[0066] Now referring to FIG. 10, the graph surface 76 shows the
minimum suggested values for the length of the fins 40 and 42, in
the upper right hand corner indicating a high horsepower and high
gross weight, it is theorize that a longer fin may be necessary
because the speed may not be as great and the centrifugal force of
the load is such that a longer fin may be necessary to promote flat
tracking. The FIG. 10 data is listed below as:
TABLE-US-00004 Weight 3.5k 10k 15k Horsepower 300 48'' 48'' 48''
400 48'' 47'' 48'' 500 48'' 50'' 55''
[0067] The following graphs in FIGS. I 1-14 are similar to that of
FIGS. 7-10 except the latter figures delayed two the parameter "D"
which is best seen in FIG. 2. It is been found that providing a
rearward gap region which is defined by the distance parameter "D"
which is defined above, is very beneficial for allowing nonaerated
water (clean water) to enter the props which is very desirable
particularly in high-performance mission-critical boating.
[0068] As shown in FIG. 11, the graph surface 78 generally
indicates that as the weight increases and/or the horsepower
decreases, the upper range of the distance parameter "D" increases.
The FIG. 11 data is listed below as:
TABLE-US-00005 Weight 3.5k 10k 15k Horsepower 300 5'' 5.5'' 6'' 400
4'' 4.5'' 5.5'' 500 3'' 4'' 5''
[0069] As shown in FIG. 12 the graph surface 80 has a similar type
of relationship indicating the lower values for the distance
parameter "D". The FIG. 12 data is listed below as:
TABLE-US-00006 Weight 3.5k 10k 15k Horsepower 300 3'' 3.5'' 4'' 400
2'' 3'' 3.5'' 500 1.5'' 2'' 3''
[0070] Now reference is made to the graphs as shown in FIGS. 13 and
14 which indicate the distance parameter "D" for 35 ft. boat with
respect to horsepower and gross weight. As shown in FIG. 13, the
graph surface 82 indicates that the upper distance parameter "D" is
substantially less dependent upon the gross weight and more of a
function of the horsepower whereby an increase in horsepower only
requires a smaller distance parameter "D". The FIG. 13 data is
listed below as:
TABLE-US-00007 Weight 3.5k 10k 15k Horsepower 300 6.1'' 6.1'' 6.1''
400 5.5'' 5.5'' 5.5'' 500 4.9'' 4.9'' 4.9''
[0071] Now referring to the surface 84 in FIG. 14, it is shown that
a minimum recommendation of about four inches is necessary for a
very heavy gross weight of 15,000 lbs. and a very low powered
engine of about 300 horsepower for a very long boat of 35 ft. The
FIG. 14 data is listed below as:
TABLE-US-00008 Weight 3.5k 10k 15k Horsepower 300 2.9'' 3.5'' 4.1''
400 2.9'' 3.25'' 3.5'' 500 2.9'' 2.9'' 2.9''
[0072] It should be noted that the graphs and parameters are
partially based upon empirical data that was acquired over many
months of testing and theoretical analysis based upon the data and
the general knowledge of fluid dynamics of the inventors. It should
be noted that the ranges as shown in FIGS. 7-14 are general
suggestions and where numerically possible (i.e. not going to
negative values) can be expanded by an estimated 20%-40% in the
broader scope. It should be further noted that it is theorize that
as shown in FIG. 1, the area of influence of the boat has a
longitudinal and lateral dimension where the longitudinal distance
86 roughly corresponds to the rearward one third length of the
boat. As shown in FIG. 3, the dimension in the lateral direction
indicated at 88 indicates a lateral area of influence which is
approximately one third of the latterly outward portion of the boat
with respect to the outer portion of the boat to the centerline of
the boat.
[0073] It is evident that various modifications could be made of
the present invention without departing from the basic teachings
thereof.
* * * * *