U.S. patent application number 11/436429 was filed with the patent office on 2007-11-22 for hybrid hull.
This patent application is currently assigned to American Sports Car Design, Inc.. Invention is credited to James C. Gregory, Rex R. Orr.
Application Number | 20070266923 11/436429 |
Document ID | / |
Family ID | 38710831 |
Filed Date | 2007-11-22 |
United States Patent
Application |
20070266923 |
Kind Code |
A1 |
Orr; Rex R. ; et
al. |
November 22, 2007 |
Hybrid hull
Abstract
An improved hybrid boat hull adapted for use with a motor. The
boat hull structure combines the handling characteristics of a
v-hull design with a speed and acceleration characteristics of a
tunnel-hull design. A transom recess is positioned approximate the
aft portion of the stern, defining an upper portion and a lower
portion which is offset forward of the upper portion. A tunnel
recess is provided which includes a forward and an aft end. The
tunnel recess cooperates with portions of the port and starboard
side, such that the handling and acceleration features of the boat
are enhanced.
Inventors: |
Orr; Rex R.; (Maryville,
TN) ; Gregory; James C.; (Friendsville, TN) |
Correspondence
Address: |
PITTS AND BRITTIAN P C
P O BOX 51295
KNOXVILLE
TN
37950-1295
US
|
Assignee: |
American Sports Car Design,
Inc.
Maryville
TN
|
Family ID: |
38710831 |
Appl. No.: |
11/436429 |
Filed: |
May 18, 2006 |
Current U.S.
Class: |
114/288 |
Current CPC
Class: |
Y02T 70/10 20130101;
B63B 39/00 20130101; B63B 2039/067 20130101; Y02T 70/122 20130101;
B63B 2001/203 20130101; B63B 39/03 20130101; B63B 1/38 20130101;
B63B 1/20 20130101 |
Class at
Publication: |
114/288 |
International
Class: |
B63B 1/32 20060101
B63B001/32 |
Claims
1. An improved boat hull of the type adapted for use with a motor,
said boat hull having a conventional V-shaped design including at
least one bow, keel, stern, port side, starboard side, port wall,
starboard wall, transom, at-rest displacement waterline, and full
planing waterline; the improvement comprising: a transom recess
positioned proximate an aft portion of said stern, said transom
recess defining a transom upper portion and a transom lower
portion, said transom lower portion being offset forward of said
transom upper portion; and, a tunnel recess having a forward end
and an aft end, said tunnel recess forward end interrupting said
keel proximate a point located along said keel, said tunnel recess
extending aft toward said stem, said tunnel recess being open at
said aft end adjacent said transom lower portion; whereby said
tunnel recess cooperates with portions of said port side and said
starboard side aft of said intersection point to define a port
sponson and a starboard sponson, each of said port sponson and said
starboard sponson defining a pad.
2. The improved boat hull of claim 1, said transom recess further
defining a spray deflector, said spray deflector connecting an
upper edge of said transom lower portion to a lower edge of said
transom upper portion.
3. The improved boat hull of claim 1, said transom recess further
defining: a first spray deflector, said first spray deflector
connecting an upper edge of said transom lower portion to a lower
edge of said transom upper portion; and, at least one additional
spray deflector, each of said at least one additional spray
deflector comprising a surface positioned substantially aft of said
transom lower portion.
4. The improved boat hull of claim 1, wherein said point between
said keel and said tunnel recess is positioned between said at-rest
displacement waterline and said full planing waterline.
5. The improved boat hull of claim 1, said tunnel recess defining a
longitudinal passageway beginning at said point and widening to
extend aft toward said stern.
6. The improved boat hull of claim 1, said tunnel recess being
substantially symmetrical about a plane defined by said keel.
7. The improved boat hull of claim 1, whereby a forward portion of
said tunnel recess is vertically tapered such that said tunnel
recess is positioned substantially above said point between said
keel and said tunnel recess.
8. The improved boat hull of claim 1, whereby: said transom recess
further defines a first spray deflector, said first spray deflector
connecting an upper edge of said transom lower portion to a lower
edge of said transom upper portion, and whereby said transom recess
further defines at least one additional spray deflector, each of
said at least one additional spray deflector comprising a surface
positioned substantially aft of said transom lower portion; said
point between said keel and said tunnel recess is positioned
between said at-rest displacement waterline and said full planing
waterline; and, said tunnel recess defines a longitudinal
passageway beginning at said point and extending aft toward said
stern, said longitudinal passageway being substantially symmetrical
about a plane defined by said keel, a forward portion of said
tunnel recess being vertically tapered such that said tunnel recess
is positioned substantially above said point between said keel and
said tunnel recess.
9. The improved boat hull of claim 1, said improvement further
comprising a counterbalancing means for limiting bow rise during
acceleration of said boat hull, said counterbalancing means
comprising a ballast cavity positioned proximate said bow above
said keel, said ballast cavity being configured substantially below
said at-rest displacement waterline such as to allow said ballast
cavity to substantially fill with water when said boat hull is
positioned in an at-rest displacement position.
10. The improved boat hull of claim 9, said counterbalancing means
comprising: a ballast cavity extending forward from said tunnel
recess forward end, said ballast cavity being positioned
substantially above said keel, said ballast cavity being configured
substantially below said at-rest displacement waterline such as to
allow said ballast cavity to substantially fill with water when
said boat hull is positioned in an at-rest displacement position;
and, a damper for regulating regulate the flow of water out of said
ballast cavity.
11. The improved boat hull of claim 9, said counterbalancing means
comprising: a ballast cavity extending forward from said tunnel
recess forward end, said ballast cavity being positioned
substantially above said keel, said ballast cavity being configured
substantially below said at-rest displacement waterline such as to
allow said ballast cavity to substantially fill with water when
said boat hull is positioned in an at-rest displacement position; a
damper for regulating the flow of water out of said ballast cavity,
said dampener comprising a screen hinged to said ballast cavity
proximate said tunnel recess forward end; and a piston connecting
said damper to said ballast cavity, said piston being configured to
allow said damper to be selectively positioned between an open and
a closed position.
12. The improved boat hull of claim 1, said improvement further
comprising: a ballast cavity extending forward from said tunnel
recess forward end, said ballast cavity being positioned
substantially above said keel, said ballast cavity being configured
substantially below said at-rest displacement waterline such as to
allow said ballast cavity to substantially fill with water when
said boat hull is positioned in an at-rest displacement position;
and, a damper for regulating the flow of water out of said ballast
cavity, said dampener comprising a screen fixedly attached to said
ballast cavity proximate said tunnel recess forward end; and
whereby, said transom recess further defines a first spray
deflector, said first spray deflector connecting an upper edge of
said transom lower portion to a lower edge of said transom upper
portion, and whereby said transom recess further defines at least
one additional spray deflector, each of said at least one
additional spray deflector comprising a surface positioned
substantially aft of said transom lower portion; said point between
said keel and said tunnel recess is positioned between said at-rest
displacement waterline and said full planing waterline; and, said
tunnel recess defines a longitudinal passageway beginning at said
point and extending aft toward said stern, said longitudinal
passageway being substantially symmetrical about a plane defined by
said keel, a forward portion of said tunnel recess being vertically
tapered such that said tunnel recess is positioned substantially
above said point between said keel and said tunnel recess.
13. An improved boat hull of the type adapted for use with a motor,
said boat hull having a conventional V-shaped design including at
least one bow, keel, stern, port side, starboard side, port wall,
starboard wall, transom, at-rest displacement waterline, and full
planing waterline; the improvement comprising: a tunnel recess
having a forward end and an aft end, said tunnel recess forward end
interrupting said keel proximate a point located along said keel,
said tunnel recess extending aft toward said stern, said tunnel
recess being open at said aft end adjacent said transom lower
portion; and a ventilation means for ventilating said tunnel
recess, said ventilation means comprising: an intake opening
positioned along an exterior surface of said bow; and, an air duct
connecting said tunnel recess to said intake opening, said air duct
being configured to allow air to enter and leave said tunnel
recess; whereby said tunnel recess cooperates with portions of said
port side and said starboard side aft of said intersection point to
define a port sponson and a starboard sponson, each of said port
sponson and said starboard sponson defining a pad.
14. The improved boat hull of claim 13, said means for ventilating
said tunnel recess comprising: an intake opening positioned
proximate a forward surface of said bow above the at-rest
displacement waterline; and, an air duct extending forward from
said tunnel recess forward end, said air duct being positioned
substantially above said keel, said air duct connecting said tunnel
recess to said intake opening, said air duct being configured to
allow air to enter and leave said tunnel recess.
15. The improved boat hull of claim 14, said means for ventilating
said tunnel recess further comprising: a damper for regulating the
flow of water out of said air duct, said dampener comprising a
screen fixed to proximate an intersection of said air duct and said
tunnel recess forward end.
16. The improved boat hull of claim 14, said means for ventilating
said tunnel recess further comprising: a damper for regulating the
flow of water out of said air duct, said dampener comprising a
screen fixed to proximate an intersection of said air duct and said
tunnel recess forward end; and a piston connecting said damper to
said ballast cavity, said piston being configured to allow said
damper to be selectively positioned between an open and a closed
position.
17. An improved boat hull of the type adapted for use with a motor,
said boat hull having a conventional V-shaped design including at
least one bow, keel, stern, port side, starboard side, port wall,
starboard wall, transom, at-rest displacement waterline, and full
planing waterline; the improvement comprising: a transom recess
positioned proximate an aft portion of said stern, said transom
recess defining a transom upper portion and a transom lower
portion, said transom lower portion being offset forward of said
transom upper portion, said transom recess further defining a first
spray deflector, said first spray deflector connecting an upper
edge of said transom lower portion to a lower edge of said transom
upper portion, said transom recess further defining at least one
additional spray deflector, each of said at least one additional
spray deflector comprising a surface positioned substantially aft
of said transom lower portion; a tunnel recess having a forward end
and an aft end, said tunnel recess forward end interrupting said
keel proximate a point located along said keel, said point between
said keel and said tunnel recess being positioned between said
at-rest displacement waterline and said full planing waterline,
said tunnel recess defining a longitudinal passageway beginning at
said point and extending aft toward said stem, said longitudinal
passageway being substantially symmetrical about a plane defined by
said keel, said tunnel recess forward portion being vertically
tapered such that said tunnel recess is positioned substantially
above said point between said keel and said tunnel recess, said
tunnel recess being open at said aft end adjacent said transom
lower portion; an intake opening positioned proximate a forward
surface of said bow above the at-rest displacement waterline; and,
an air duct connecting said tunnel recess forward end to said
intake opening, said air duct being configured to allow air to
enter and leave said tunnel recess; whereby said tunnel recess
cooperates with portions of said port side and said starboard side
aft of said intersection point to define a port sponson and a
starboard sponson, each of said port sponson and said starboard
sponson defining a pad.
18. An improved boat hull of the type adapted for use with a motor,
said boat hull having a conventional V-shaped design including at
least one bow, keel, stern, port side, starboard side, port wall,
starboard wall, transom, at-rest displacement waterline, and full
planing waterline; the improvement comprising: a transom recess
positioned proximate an aft portion of said stern, said transom
recess defining a transom upper portion and a transom lower
portion, said transom lower portion being offset forward of said
transom upper portion, said transom recess further defining a first
spray deflector, said first spray deflector connecting an upper
edge of said transom lower portion to a lower edge of said transom
upper portion, said transom recess further defining at least one
additional spray deflector, each of said at least one additional
spray deflector comprising a surface positioned substantially aft
of said transom lower portion; a tunnel recess having a forward end
and an aft end, said tunnel recess forward end interrupting said
keel proximate a point located along said keel, said point between
said keel and said tunnel recess being positioned between said
at-rest displacement waterline and said full planing waterline,
said tunnel recess defining a longitudinal passageway beginning at
said point and extending aft toward said stem, said longitudinal
passageway being substantially symmetrical about a plane defined by
said keel, said tunnel recess forward portion being vertically
tapered such that said tunnel recess is positioned substantially
above said point between said keel and said tunnel recess, said
tunnel recess being open at said aft end adjacent said transom
lower portion; an intake opening positioned proximate a forward
surface of said bow above the at-rest displacement waterline; an
air duct connecting said tunnel recess forward end to said intake
opening, said air duct being configured to allow air to enter and
leave said tunnel recess; a ballast cavity extending forward from
said tunnel recess forward end, said ballast cavity being
positioned substantially above said keel, said ballast cavity being
configured substantially below said at-rest displacement waterline
such as to allow said ballast cavity to substantially fill with
water when said boat hull is positioned in an at-rest displacement
position, a damper for regulating the flow of water out of said
ballast cavity, said dampener comprising a screen hinged to said
ballast cavity proximate said tunnel recess forward end; and a
piston connecting said damper to said ballast cavity, said piston
being configured to allow said damper to be selectively positioned
between an open and a closed position; whereby said tunnel recess
cooperates with portions of said port side and said starboard side
aft of said intersection point to define a port sponson and a
starboard sponson, each of said port sponson and said starboard
sponson defining a pad.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Not Applicable
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable
BACKGROUND OF THE INVENTION
[0003] 1. Field of Invention
[0004] This invention pertains to boat hull structures. More
particularly, this invention pertains to a hybrid hull structure
which combines handling characteristics of a V-hull design with the
speed and acceleration characteristics of a tunnel-hull design.
[0005] 2. Description of the Related Art
[0006] Power boats display different operating characteristics
depending on the shape of their hulls. Many hulls have been
previously designed in an attempt to decrease the resistance of the
hull moving across the water surface and to increase the
directional stability of the hull while moving through or over the
water. Attempts to achieve both of these objectives have often
involved a compromise between decreased hull resistance and
increased directional stability, due to the problems involved in
achieving both of these advantages.
[0007] To decrease the hull resistance of a boat, one common hull
design is a flat bottom, since it draws a low amount of water for
its weight. The flat bottom hull is a classic example of a planing
hull which tends to climb above the water to a full planing
position from its at-rest displacement position. However, the flat
bottom hull lacks directional stability, and the hull bottom is
often subjected to impact from passing waves.
[0008] On the other hand, a more stable and softer riding hull in
rough or choppy water is the V hull. The V hull typically has a
V-shaped (or cathedral-shaped) cross-section with a low keel
running from the bow to the transom. The V-shaped cross-section of
the V hull is capable of cutting through waves and transitioning
smoothly between an at-rest displacement position to a full planing
position. Therefore, V hulls are capable of providing a smooth
ride, seaworthiness and good handling and steering characteristics.
However, because the V hull often has a wetted area (portion of
hull contacting the water surface) larger than flat bottom hulls,
the V hull provides considerably more resistance when moving, thus
resulting in considerable loss of planing performance. The V hull
typically displays lateral instability, slide slipping or tipping
during turns as water pushes against the keel of the V hull. Also,
the V hull is susceptible to capsizing in waves or choppy water
when the hull direction is at an angle, that is, not perpendicular
to the waves. Moreover, the increased resistance of the V hull
often causes the bow of a V hull boat to rise considerably during
acceleration, resulting in a temporary decrease in forward
visibility during acceleration from the at-rest displacement
position to the full planing position.
[0009] Attempts to decrease bow rise during acceleration while
alleviating the problem of the V hull's tendency to tip over in
turning situations have resulted in utilization of tunnel hulls.
Tunnel hull boats utilize a large channel running along the middle
of the hull with multiple sponsons that extend the entire length of
the hull. Tunnel hull boats are designed to trap air underneath the
boat hull as the boat moves through water, thereby compressing the
air and lifting the boat above the water line defined by the boat's
natural buoyancy. This lifting typically results in decreased bow
rise during acceleration, and the effect of lifting the boat
decreases the boat's resistance through the water, allowing for
faster acceleration and greater boat speeds. Furthermore, the
entrapment of air underneath the boat hull typically results in
aeration of the water beneath the boat hull. This aerated water
typically displays more desirable hydrodynamic characteristics than
water that is unaerated, resulting in decreased boat hull
resistance as the hull travels through the water and therefore
increased hull speed.
[0010] Conventional tunnel hull designs have inherently sacrificed
handling characteristics for higher speed performance. In
particular, the performance of a conventional tunnel hull is load
sensitive and sea state dependent. In other words, heavy loads
detract from the air capturing and speed enhancing ability of
tunnel hulls. Lighter loaded tunnel hull boats subjected to rapid
acceleration are susceptible to poling, that is, capsizing end over
end due to the lift provided by the tunnel hull entrapment. Also,
as compared to the more traditional V hull, tunnel hulls are less
stable in choppy water or in low-speed travel such as during
acceleration from the at-rest displacement position.
[0011] Several devices have been developed in an attempt to combine
the characteristics of multiple traditional hull designs to
decrease hull resistance while increasing hull stability. Typical
of the art are those devices disclosed in the following U.S.
patents: TABLE-US-00001 Patent No. Inventor(s) Issue Date 3,996,869
Robert O. Hadley Dec. 14, 1976 4,165,703 Donald E. Burg Aug. 28,
1979 4,587,918 Donald E. Burg May 13, 1986 5,231,949 Robert Hadley
Aug. 3, 1993 5,265,554 Wilbur R. Meredith Nov. 30, 1993 5,833,502
Carl J. Anderson Nov. 10, 1998 6,216,622 Lindstrom/Kirkham Apr. 17,
2001 6,406,341 Christopher S. Morejohn Jun. 18, 2002 6,708,642 B1
Ian A. Taylor Mar. 23, 2004
[0012] Of these patents, U.S. Pat. No. 3,996,869 (the '869 patent),
U.S. Pat. No. 5,231,949 (the '949 patent), U.S. Pat. No. 5,265,554
(the '554 patent), and U.S. Pat. No. 6,216,622 B1 (the '622 patent)
each disclose a substantially V-shaped central hull portion and a
pair of adjacent sponsons. In each invention, the central hull
portion and the sponsons begin proximate the bow of the hull and
extend towards the stern. In both the '869 patent and the '949
patent, the inner walls of the sponsons are substantially vertical,
and the sponsons are stepped upwardly at approximately midships,
such that the rear portions of the sponsons are substantially
horizontal, or parallel to the plane of the water surface. In the
'622 patent, the hull includes mid hull sponsons and outer
sponsons. The mid hull sponsons form longitudinal tunnels with
adjacent central hull portions and outer sponsons. The outer
sponsons engage and deflect side directed spray and wake
downwardly, providing additional lift and decreasing or eliminating
spray and signature wake. In each of these patents, the central
hull and the sponsons form air tunnels which induce air beneath the
hull and decrease frictional engagement of the hull with water,
thereby improving the efficiency of the hull.
[0013] In U.S. Pat. No. 4,165,703 (the '703 patent), issued to
Donald E. Burg, a V hull having an air chamber substantially aft of
midships and entirely beneath the waterline is disclosed. The '703
patent includes an air supply duct with a pressure control valve,
providing injected air to the air chamber, thereby reducing the pad
(wetted area of the hull during planing) and improving hull
efficiency without substantially altering the V hull handling
characteristics.
[0014] U.S. Pat. No. 4,587,918 (the '918 patent), also issued to
Donald E. Burg, discloses a hull with one or more recesses that
intersect the hull substantially beneath the waterline. In the '918
patent, each recess is bounded by catamaran-like sidehulls with bow
shaped members located at the forward and aft portions of the
recess. The fore and aft bow shaped members contact the water like
small bow sections, thereby improving hull ride and handling
characteristics. The keels of the sidehulls diverge to allow narrow
or fine entry forward. Like the '703 patent, the recess of the '918
patent is supplied with pressurized gas to maintain a
lift-augmenting, restrained pressurized gas layer under the
hull.
[0015] Carl J. Anderson in U.S. Pat. No. 5,833,502 (the '502
patent) discloses a deep V-shaped forward section and a rear tunnel
section extending longitudinally aft from midships. In the '502
patent, a vertically adjustable outboard motor is positioned at the
forward end of the rear tunnel section. The center mounting of the
engine in conjunction with the tunnel section of the hull reduces
planing upon acceleration, improves center of gravity and reduces
the risk to swimmers and water skiers from a rear mounted
propeller.
[0016] U.S. Pat. No. 6,406,341 (the '341 patent), issued to
Christopher S. Morejohn, discloses a shallow draft sports boat
having a water tunnel in its bottom allowing one to place an
outboard motor higher with respect to the hull of the boat than is
conventional. In the '341 patent, the water tunnel is relatively
short with respect to the overall length of the boat, has a small
volume and is provided with a recess at its leading end. A vent
communicates between the recess and a port in the transom above the
water line to remove air entrainment from water that passes through
the tunnel.
[0017] Finally, Ian A. Taylor, in U.S. Pat. No. 6,708,642 B1 (the
'642 patent), discloses a hull having an upper flat bottom section
and a pair of outer sponsons extending from a forward portion to a
stern portion of the bottom of the flat bottom section. The pair of
outer sponsons cooperate with the upper flat bottom section to
define a tunnel, and an elongated center sponson extends along the
bottom of the flat bottom section substantially parallel to the
pair of outer sponsons. The center sponson has a forward section
with an upwardly extending trailing step wall defining an upward
step in the center sponson. An aft section of the center sponson
has an upwardly curved leading edge intersecting the step wall of
the forward section.
BRIEF SUMMARY OF THE INVENTION
[0018] According to one embodiment of the present invention, is
provided.
[0019] Another embodiment provides
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0020] The above-mentioned features of the invention will become
more clearly understood from the following detailed description of
the invention read together with the drawings in which:
[0021] FIG. 1 is a side elevation view of a hybrid hull constructed
in accordance with several features of the present invention;
[0022] FIG. 2 is a bottom view of the hybrid hull of FIG. 1;
[0023] FIG. 3 is a stem elevation view of the hybrid hull of FIG.
1;
[0024] FIG. 4 is a bottom view of a traditional prior-art V-shaped
hull, showing the pad below the full planing waterline;
[0025] FIG. 5 is a bow elevation of another embodiment of a hybrid
hull constructed in accordance with the present invention;
[0026] FIG. 6 is a side elevation view of the embodiment of the
hybrid hull shown in FIG. 5;
[0027] FIG. 7 is a side elevation of another embodiment of a hybrid
hull constructed in accordance with the present invention, showing
the hybrid hull partially immersed in water in its at-rest
displacement position;
[0028] FIG. 8 is a side elevation of the alternative embodiment of
the hybrid hull shown in FIG. 7, showing the hybrid hull
accelerating to its planing position with water draining from the
ballast cavity;
[0029] FIG. 9 is a side elevation of another embodiment of a hybrid
hull constructed in accordance with the present invention;
[0030] FIG. 10 is a bottom view of the embodiment of the hybrid
hull shown in FIG. 9.
DETAILED DESCRIPTION OF THE INVENTION
[0031] A hybrid hull for increasing the directional stability of a
boat hull while decreasing water resistance during planar movement
is disclosed. The hybrid hull of the present invention, illustrated
at 10 in the figures, combines the handling characteristics of a V
hull design with the speed and stability of a tunnel hull design.
Furthermore, the hybrid hull limits the possibility of poling by
limiting excess air entrapment beneath the hull during high speed
motion.
[0032] FIG. 1 is a partially cut away side elevation view of a
hybrid hull 10 constructed in accordance with several features of
the present invention. The hull 10 includes a bow 12 with a keel
14, and a stem 16. The bow 12 defines a starboard side 20 and a
port side 22 intersecting in a traditional V-shaped configuration.
The bow 12 begins at a forward point 24 and widens aft for
stability. The keel 14 begins at the forward point 24 and extends
aft along the intersection between the port side 22 and the
starboard side 20, defining a cutting edge that allows the hybrid
hull 10 to cut through the water and any waves. A port wall 21 and
a starboard wall 23 begin at the forward point 24 and widen to
extend substantially upward along the outer edges of the port and
starboard sides 22, 20.
[0033] The stem 16 of the hybrid hull includes a transom 26
defining a rear surface of the hull 10. The transom connects rear
edges of the port and starboard walls 21, 23 to the port side 22
and the starboard side 20. A lower portion 28 of the transom 26 is
offset forward from a transom upper portion 30 by a transom recess
32. The transom recess 32 of the hybrid hull 10 decreases water
resistance, thereby improving the efficiency of the hull 10. The
transom recess 32 also increases the speed at which the hybrid hull
10 achieves its planing position during acceleration. As discussed
in greater detail below, the configuration of the transom recess 32
offsetting the transom lower portion 28 forward from the transom
upper portion 30 allows the bow 12 to rise as the hybrid hull 10 is
propelled forward to achieve water-surface planing. In the
illustrated embodiment, the transom upper portion 30 further
includes a motor well 19 defined by a recessed portion of the
transom upper portion 30. The motor well 19 is adapted to receive a
conventional propulsive device, such as an outboard motor (not
shown). Of course, those skilled in the art will recognize that the
inclusion of the motor well 19 is not necessary to achieve the
present invention.
[0034] The top edge 29 of the transom lower portion 28 is connected
to the lower edge 31 of the transom upper portion 30 by a spray
deflector 18 defining a surface configured substantially parallel
to the plane defined by an at-rest displacement waterline 38. The
spray deflector 18 serves to limit the upward spray of the wake
resulting from the forward propulsion of the hybrid hull 10 through
water. In the illustrated embodiment, a plurality of additional
spray deflectors 25, 27 extend aft from the transom lower portion
28. As illustrated, these deflectors 25, 27 define a series of
step-shaped protrusions extending aft from the transom lower
portion 28. It is appreciated that other shapes can be used in
various configurations to accomplish the present invention. To this
extent, it is understood that inclusion of the additional spray
deflectors 25, 27 is not necessary to achieve the present
invention.
[0035] The keel 14 is interrupted by a tunnel recess 34 at a point
36 located between the at-rest displacement waterline 38 and a full
planing waterline 40. The tunnel recess 34 defines a longitudinal
passageway running from the keel point 36 and extending aft toward
the stem 16. The tunnel recess 34 is provided with a vertically
tapered forward end such that the tunnel recess 34 opens
substantially upward into the hybrid hull 10. This configuration is
designed to limit the entrapment of frontal air into the tunnel
recess 34 while the hybrid hull 10 is in a full planing position.
The tunnel recess 34 intersects at 42 with the transom lower
portion 28, such that the aft portion of the tunnel recess 34
adjacent said transom lower portion 28 is open. In the illustrated
embodiment, the configuration of the tunnel recess 34 relative to
the at-rest displacement waterline 38 and the full planing
waterline 40 is such that the tunnel recess 34 is completely
submerged when the hybrid hull 10 is in an at-rest displacement
position and partially submerged when the hybrid hull 10 is in a
full planing position. However, those skilled in the art will
recognize other possible configurations between the tunnel recess
34 and the at-rest displacement and full planing waterhnes 38, 40
which can be used without departing from the spirit and scope of
the present invention.
[0036] In FIG. 2, a bottom view of the illustrated embodiment of
the present invention better illustrates the shape and
configuration of the spray deflectors 18, 25, 27, proximate the
tunnel recess 34. The tunnel recess 34 is symmetrical about the
plane defined by the keel 14. The lateral dimension of the tunnel
recess forward portion 46 is tapered such that the tunnel recess 34
begins at the intersection point 36 and widens to extend aft. The
perimeter 44 of the tunnel recess 34 is beneath the at-rest
displacement waterline 38. However, the intersection point 36 of
the tunnel recess 34 with the keel 14 is positioned above the full
planing waterline 40, such that the forward portion 46 of the
tunnel recess 34 is exposed to the air during full planing.
[0037] FIG. 3 is a stem elevation view of the hybrid hull 10 of the
present invention, showing the intersection 42 of the tunnel recess
34 with the transom lower portion 28. In the illustrated
embodiment, the sidewalls 48, 50 of the tunnel recess 34 cooperate
with port and starboard sides 20, 22 to define a port sponson 52
and a starboard sponson 54. The port and starboard sponsons 52, 54
begin at the intersection point 36 of the keel 14 and the tunnel
recess 34 and extend the full length of the tunnel recess 34,
terminating at the intersection 42 of the tunnel recess 34 with the
transom lower portion 28. The point 36 of the keel 14 and the
tunnel recess 34 is positioned sufficiently aft of the bow that the
point 36 substantially aligns with the plane defined by the lower
edges of the sponsons 52, 54. The configuration of the sponsons 52,
54 is such that the sponsons 52, 54 act as a pair of running
surfaces while the bow 12 and keel 14 act to break or piece waves
in heavy seas and to cut through the water surface. In this
respect, the sponsons 52, 54 compliment the bow 12 by providing
lateral stability to the hybrid hull 10 while the bow 12 and keel
14 provide directional stability.
[0038] Referring to FIG. 1, when a forward force is applied to the
transom upper portion 30, water surrounding the bow 12 pushes
against the starboard and port sides 20, 22, tending to cause the
bow 12 to lift. The configuration of the transom lower portion 28,
offset forward from the transom upper portion 30, allows the hybrid
hull 10 to pivot upward about the transom recess 32. This pivoting
action further causes the bow 12 to rise as the hybrid hull 10 is
propelled forward. As the bow 12 rises during acceleration, the
forward portion 46 of the tunnel recess 34 is exposed. At the same
time, passing water pushes against the stern 14, causing the stern
to lift. The exposed portion 46 of the tunnel recess 34 channels
air into the tunnel, providing additional lift to the rear of the
hybrid hull 10. As this combined lifting force raises the stem 14
into a full planing position, the bow 12 lowers proximate the stem
14, and the tunnel recess 34 returns to a more level configuration.
Hence, the bow 12 and keel 14 move to partially block the forward
exposure of the tunnel recess 34, and the tapered front portion 46
of the tunnel recess 34 limits air entrapment beneath the hybrid
hull 10. As the hybrid hull 10 travels forward, the limited amount
of air entrapped beneath the hull serves to aerate the water
beneath the stern 14, thus providing a softer and less resistant
aerated water surface beneath the hybrid hull 10.
[0039] The tunnel recess 34 further serves to reduce the frictional
wetted area of the hybrid hull 10, as compared to a typical V-hull
design. The pad 56' of a typical prior-art V-hull is illustrated in
FIG. 4. In the prior art design, the pad 56' is defined by the
portion of the hull positioned below the full planing waterline 40.
The pad 56 of the hybrid hull is shown in FIG. 2. As illustrated,
as the hybrid hull 10 achieves a full planing position, the tunnel
recess 34 becomes filled with channeled air. Thus, the tunnel
recess 34 serves to reduce the pad 56 of the hybrid hull 10 during
planing. As shown in FIG. 2, the pad 56 of the illustrated
embodiment is defined only by those portions of the sponsons 52, 54
extending below the full planing waterline 40. By reducing the
overall area of the pad 56 of the hybrid hull 10 during planing,
the tunnel recess 34 reduces the overall resistance exerted by
water against the hybrid hull 10 and increases the efficiency of
the hull design.
[0040] FIGS. 5 and 6 show another embodiment of a hybrid hull
10'constructed in accordance with the present invention. As shown
in the bow elevation view shown in FIG. 5, the hybrid hull
10'defines an air duct 62 having a plurality of intake openings 58,
60 positioned above the at-rest displacement waterline 38'
proximate the forward surfaces of the bow 12'. As illustrated, the
air duct 62 connects the tunnel recess 34' to the intake openings
58, 60 on the port and starboard sides 22', 20'. In the illustrated
embodiment, each of the intake openings 58, 60 is defined by a
boring in the forward portions of the port and starboard sides 22',
20'. The air duct 62 connects two intake openings 58, 60 to the
tunnel recess 34'. Of course, those skilled in the art will
recognize that more or fewer air ducts can be utilized in a variety
of configurations without departing from the spirit and scope of
the present invention. The air duct 62 and corresponding intake
openings 58, 60 are positioned in a substantially symmetrical
configuration about the keel 14, in order to reduce imbalance of
the hybrid hull 10' during motion. However, the non-symmetrical
configuration of air ducts and intake openings along the bow 12' is
contemplated.
[0041] FIG. 6 shows a partially cut away side elevation view of the
present embodiment. As shown in FIG. 6, the air duct 62 is
configured such as to allow air to enter and leave the tunnel
recess 34' while the hybrid hull 10' is underway. This feature
provides several advantages. As the hybrid hull 10' begins forward
motion from an at-rest displacement position, the air duct 62
allows air to fill the tunnel recess 34, dissipating any hydraulic
suction which may result from water within the tunnel recess 34.
Once the hybrid hull 10' achieves planing position, the air duct 62
allows air to flow into the tunnel recess 34 and beneath the stern
14, where the additional air provides additional aeration to the
water beneath the hybrid hull 10'.
[0042] A further embodiment of the hybrid hull is illustrated at
10'' in FIGS. 7 and 8. Referring to FIG. 7, the hybrid hull 10'' is
partially immersed in water in its at-rest displacement position. A
forward portion of the tunnel recess 34'' is intersected by a
ballast cavity 66. The ballast cavity 66 extends forward into the
bow 12'' above the keel 14''. At least a portion of the ballast
cavity 66 is positioned substantially below the at-rest
displacement waterline 38''. This configuration allows the ballast
cavity 66 to partially fill with water as the ballast cavity is
partially submerged below the surface of the water.
[0043] A damper 68 is movably positioned proximate the interface
between the tunnel recess 34'' and the ballast cavity 66. The
damper 68 serves to regulate the flow of water out of the ballast
cavity 66 and to limit debris from entering the ballast cavity 66.
In the illustrated embodiment, the damper 68 comprises a screen
hinged to the interface between the tunnel recess 34'' and the
ballast cavity 66. Of course, those skilled in the art will
recognize other devices suitable for use to accomplish the damper
68. In the illustrated embodiment, a piston 70 connects the damper
68 to the ballast cavity 66. The hybrid hull 10'' includes controls
(not shown) for the piston 70 sufficient to allow a user to
selectively position the damper 68 between an open and a closed
position. Those skilled in the art will recognize other devices and
configurations suitable for use in limiting the inward flow of
debris to the ballast cavity while regulating the outward flow of
water. To this extent, it is appreciated that the damper 68 may be
fixed to substantially cover the interface between the tunnel
recess 34'' and the ballast cavity 66 without departing from the
spirit and scope of the present invention.
[0044] FIG. 8 illustrates the present embodiment of the hybrid hull
10'' accelerating to its planing position. As the hybrid hull 10''
is propelled forward, the bow 12'' tends to rise as water
resistance is applied to starboard and port sides 20, 22. The
damper 68 restricts the flow of water from the ballast cavity 66,
and the water-filled ballast cavity 66 acts as a forward
counterbalance to limit bow rise during acceleration. As shown in
FIG. 8, the damper 68 causes water within the ballast cavity 66 to
drain from the ballast cavity 66 at a controlled rate as the hybrid
hull 10'' lifts above the at-rest displacement waterline 38''. As
the hybrid hull 10'' achieves a full planing position, the ballast
cavity 66 empties, thereby decreasing the hull weight proximate the
bow 12'' and increasing the speed capabilities of the hybrid hull
10'' while in motion along the full planing waterline 40''. With
the ballast cavity 66 empty, the user is able to selectively
position the damper 68 to an open position, thereby allowing water
to fill the ballast cavity 66 upon deceleration of the hybrid hull
10''.
[0045] Another embodiment of the hybrid hull is illustrated at
10''' in FIGS. 9 and 10. As illustrated, the embodiment of FIGS. 9
and 10 includes the air duct 62 having a plurality of intake
openings 58, 60 positioned above the at-rest displacement waterline
38' proximate the forward surfaces of the bow 12'. As illustrated,
the air duct 62 connects the tunnel recess 34' to the intake
openings 58, 60 on the port and starboard sides 22', 20'. As shown
in the bottom view of FIG. 10, a damper 68 is movably positioned
proximate the interface between the tunnel recess 34'' and the
ballast cavity 66. A piston 70 connects the damper 68 to the
ballast cavity 66, and controls (not shown) for the piston 70 are
provided to allow a user to selectively position the damper 68
between an open and a closed position.
[0046] In this embodiment, the air duct 62 partially fills with
water when the hybrid hull 10''' is in an at-rest position. As the
hybrid hull 10''' is propelled forward, the damper 68 restricts the
flow of water from the air duct 62, and the partially water-filled
air duct 62 acts as a forward counterbalance to limit bow rise
during acceleration. As the hybrid hull 10''' achieves a full
planing position, the air duct 62 empties, thereby decreasing the
hull weight proximate the bow 12''' and increasing the speed
capabilities of the hybrid hull 10'''. With the air duct 62 empty,
the user is able to selectively position the damper 68 to an open
position, thereby allowing air to fill the tunnel recess 34 and
dissipating any hydraulic suction which may result from water
within the tunnel recess 34. Once the hybrid hull 10''' achieves
planing position, the air duct 62 allows air to flow into the
tunnel recess 34 and beneath the stem 14, where the additional air
provides additional aeration to the water beneath the hybrid hull
10'''.
[0047] From the foregoing description, it will be recognized by
those skilled in the art that several embodiments of a hybrid hull
have been provided. The hybrid hull of the present invention
combines the handling characteristics of a V hull design with the
speed and acceleration characteristics of a tunnel hull design. The
transom recess feature of the hybrid hull decreases water
resistance while increasing the speed at which the hybrid hull
achieves its planing position during acceleration by encouraging
rapid bow rise and allowing more immediate lift to planing position
than the traditional V hull design.
[0048] While the present invention has been illustrated by
description of several embodiments and while the illustrative
embodiments have been described in considerable detail, it is not
the intention of the applicant to restrict or in any way limit the
scope of the appended claims to such detail. Additional advantages
and modifications will readily appear to those skilled in the art.
The invention in its broader aspects is therefore not limited to
the specific details, representative apparatus and methods, and
illustrative examples shown and described. Accordingly, departures
may be made from such details without departing from the spirit or
scope of applicant's general inventive concept.
* * * * *