U.S. patent application number 12/074323 was filed with the patent office on 2009-09-03 for towable underwater craft.
Invention is credited to Eric Healy.
Application Number | 20090217859 12/074323 |
Document ID | / |
Family ID | 41012201 |
Filed Date | 2009-09-03 |
United States Patent
Application |
20090217859 |
Kind Code |
A1 |
Healy; Eric |
September 3, 2009 |
TOWABLE UNDERWATER CRAFT
Abstract
A towable underwater craft includes a main body contoured to
support the rider in the prone position, a contoured leading edge,
left and right arm guards, left and right independently actuated
hydrofoils and a tow rope. The majority of the craft is constructed
from a foam core and a fiber-reinforced polymer exterior to provide
the required buoyancy and strength. The tow rope is attached at one
end to a powered water craft and to the craft at the opposite end.
The pitch of the left and right hydrofoils are controlled
independently by the rider. This actuation controls both the depth
and roll of the craft enabling the rider to fully control the craft
below the surface of the water while being towed.
Inventors: |
Healy; Eric; (Bend,
OR) |
Correspondence
Address: |
Eric W. Healy
20532 Rusticate Road
Bend
OR
97702
US
|
Family ID: |
41012201 |
Appl. No.: |
12/074323 |
Filed: |
March 3, 2008 |
Current U.S.
Class: |
114/315 |
Current CPC
Class: |
B63G 8/42 20130101; B63C
2011/028 20130101; B63C 11/46 20130101 |
Class at
Publication: |
114/315 |
International
Class: |
B63C 11/46 20060101
B63C011/46 |
Claims
1. A towable submersible craft, comprising: a main body defining a
platform configured for accommodating a rider, the main body having
a leading edge and a trailing edge with a center of pressure
between the leading and trailing edges, and opposed lateral sides;
a first hydrofoil pivotally attached to one of the opposed lateral
sides of the main body with a shaft journaled to the main body at a
shaft axis and a second hydrofoil pivotally attached to the
opposite lateral side of the main body at a shaft journaled to the
main body coaxially With the shaft axis, each hydrofoil
independently pivotal about the shaft axis relative to the main
body; and a tow rope attachment point rearward of the shaft
axis.
2. The towable submersible craft according to claim 1 wherein each
hydrofoil is controlled by rotation of the hydrofoil about the
shaft axis and each hydrofoil includes a control handle that is
housed in a forwardly closed housing.
3. The towable submersible craft according to claim 2 wherein each
hydrofoil may be independently pivoted relative to said main body
to allow independent pitch actuations of said hydrofoils by
actuation of said control handles.
4. The towable submersible craft according to claim 1 wherein the
tow rope attachment is defined by a pair of attachment members
configured for attachment to a forked tow rope, each attachment
member attached to the main body near the opposed lateral edges and
forward of said center of pressure.
5. The towable submersible craft according to claim 1 wherein said
craft has positive buoyancy.
6. The towable submersible craft according to claim 5 wherein the
main body is composed of a reinforced polymer exterior and a foam
core.
7. The towable submersible craft according to claim 5 wherein the
hydrofoils are composed of a reinforced polymer exterior and a foam
core.
8. A towable submersible craft, comprising: a main body having
positive buoyancy, said main body having a hydrodynamically shaped
leading edge, a trailing edge, and opposed lateral side edges; a
first hydrodynamically shaped hydrofoil pivotally attached to one
of the opposed lateral side edges with a shaft defining a shaft
axis and a second hydrodynamically shaped hydrofoil pivotally
attached to the opposite lateral side of the main body with a shaft
coaxially aligned with the shaft axis, each hydrofoil independently
pivotal relative to the main body; and tow rope attachment means
for attaching the main body to a tow rope, said tow rope attachment
means on the main body rearward of the shaft axis.
9. The towable submersible craft according to claim 8 wherein the
main body defines a center of pressure and the tow rope attachment
means is defined by a pair of attachment members forward of the
center of pressure.
10. The towable submersible craft according to claim 9 wherein each
of the attachment members in the pair is attached to an underside
of the main body near one of the opposed lateral side edges.
11. The towable submersible craft according to claim 10 configured
for attachment to a forked tow rope.
12. A hydrodynamically efficient towable underwater craft,
comprising: a main body having positive buoyancy, said main body
defining a central portion configured for accommodating a rider and
said main body having a leading edge, a trailing edge, and opposed
lateral side edges, wherein a center of pressure is defined between
the leading and trailing edges, said main body having a
longitudinal centerline; a first hydrofoil attached to one of the
opposed lateral side edges at a shaft axis; a second hydrofoil
attached to the opposite lateral side edge at the shaft axis, each
hydrofoil independently pivotal relative to the main body about the
shaft axis and each hydrofoil having a control handle housed in a
forwardly-closed housing; a tow rope attachment rearward of the
shaft axis and forward of the center of pressure.
13. The hydrodynamically efficient towable underwater craft
according to claim 12 including two tow rope attachments, each
rearward of the shaft axis and forward of the center of pressure,
and each located on opposite sides of the longitudinal centerline
of the craft.
Description
FIELD OF THE INVENTION
[0001] This invention relates to water sport devices designed to be
towed behind a powered water craft, specifically to an improved
device that is capable of submerging below the surface of the water
with depth and roll controlled by a rider.
BACKGROUND OF THE INVENTION
[0002] There are many different kinds of water sport devices
designed to be towed behind a powered watercraft, such as a power
boat. The most popular of devices have been strictly for use on the
surface of the water. These devices include water skis, kneeboards
and wakeboards and have been widely successful. Their success
suggests potential for a devise that can travel above and below the
surface while being controlled by the rider.
[0003] Another category of water sport devices are designed to be
submersible, and several types of submergible devices have been
proposed-for example, U.S. Pat. No. 6,612,254 (2002) to Arthur,
U.S. Pat. No. 6,561,116 (2001) to Linjawi, U.S. Pat. No. 6,145,462
(1999) to Aquino, U.S. Pat. No. 5,605,111 (1995) to Culpepper, U.S.
Pat. No. 5,178,090 (1991) to Carter and U.S. Pat. No. 5,134,955
(1991) to Manfield all describe a variety of devices that are
capable of being submerged.
[0004] The device described in U.S. Pat. No. 6,612,254 is a towable
underwater "kite" that has independently operated symmetrical wings
positioned near the leading and trailing edges of the main body.
The main body of the kite is defined by parallel support members
(e.g., plastic tubes) that are interconnected with transverse
struts on their ends. This defines a belly board on which the user
lies in a prone position, horizontal in operation. The user
operates the forward wings with his or her hands, and the rear
wings with his or her feet.
[0005] The device described in U.S. Pat. No. 6,561,116 is a towable
sub-aqua device that has two independently operated maneuvering
planes positioned on opposite lateral sides. The main body of the
device is defined by support member comprises a U-shaped bar. Each
maneuvering plane has a protruding bar that is pivotally attached
to the main U-shaped bar. Each protruding bar is bent 90 degrees at
the inboard end making a handle.
[0006] The device described in U.S. Pat. No. 6,145,462 is a towable
diver aid that has a support platform pivotally mounted within a
rigid linking tubular frame. The diver is positioned on the support
platform in the prone position and controls the depth by rotating
the platform relative to the tubular frame.
[0007] The device described in U.S. Pat. No. 5,178,090 is an
underwater diving plane that has a triangular aluminum frame. The
device has a detachable transverse axle which is pivotally
connected to the main frame, having two ends and two planes fixedly
attached to the axle giving the diver depth control.
[0008] While the foregoing devices represent improvements in the
field of technology, they also have certain disadvantages. For
example, the devices described above produce lift in the downward
direction when the rider directs the hydrofoils down. Buoyancy is
critical for the craft to perform optimally. The majority of the
prior art uses a metal tubular frame which does not provide this
required buoyancy. This is a major disadvantage in that, the craft
will not rise to the surface on it's own in the event that the
rider comes off or becomes incapacitated.
[0009] Further, the majority of the known prior art devices use a
metal or plastic tubular frame. This limits the craft to a very
basic design. It does not allow the craft to be contoured around
the rider's body. This is required to support the rider in the
prone position. In addition, it is required to deflect the oncoming
water around the rider and provide a hydrodynamic shape. Directing
the oncoming water around the rider reduces the drag felt by the
rider. This allows for higher speeds and more maneuverability. The
lack of proper contouring by the prior art also makes the rider
vulnerable to the oncoming obstacles and debris.
[0010] There is an ongoing need and opportunity therefore for
improved submersible watercraft designed to be towed behind another
craft.
[0011] Accordingly, several objects and advantages of my invention
are:
[0012] (a) to provide a craft that is constructed of modern
composite materials consisting of a sufficiently buoyant foam core
and fiber reinforced polymer exterior allowing for sufficient
buoyancy to counter the downward lift and provide depth
control.
[0013] (b) to provide a craft that is constructed of modern
composite materials consisting of a sufficiently buoyant foam core
and a fiber reinforced polymer exterior allowing the craft to
automatically come to the surface in the event that the rider comes
off or becomes incapacitated.
[0014] (c) to provide a craft that is constructed of modern
composite materials consisting of a foam core and a sufficiently
ridged fiber reinforced polymer exterior allowing for complex
contours that house the rider in the prone position.
[0015] (d) to provide a craft that is constructed of modern
composite materials consisting of a foam core and a sufficiently
ridged fiber reinforced polymer exterior allowing for complex
contours that deflect the oncoming water around the rider while
providing low drag, increased speeds and better
maneuverability.
[0016] (e) to provide a craft that is constructed of modern
composite materials consisting of a foam core and a sufficiently
ridged fiber reinforced polymer exterior allowing for complex
contours that wrap around the rider's hands, forearms, upper torso
and shoulders to provide protection to the rider from oncoming
obstacles and debris.
[0017] Other objects and advantages are to provide a craft that has
two independently actuated hydrofoils where each hydrofoil is
symmetric about its cord so that in its natural position, or when
there is no control input from the rider, it produces no lift
whereby allowing for the built in buoyancy to raise the craft to
the surface. It is essential to the rider's safety that the craft
raise to the surface without any control input. Further objects and
advantages are to provide rapid ascent capabilities controlled by
the rider. This is accomplished by placing the hydrofoils ahead of
the point of pitch rotation on the craft, or the point where the
tow line attaches, allowing the entire craft to pitch up when the
hydrofoils are deflected up causing an increased ascent and further
increasing the safety. Still further objects and advantages will
become apparent from a consideration of the ensuing description and
drawings.
[0018] In accordance with the present invention a towable under
water craft comprising a main body contoured to a rider's upper
torso, two independently actuated hydrofoils for controlling depth
and roll and a tow line for attaching the craft to a powered water
craft.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The invention will be better understood and its numerous
objects and advantages will be apparent by reference to the
following detailed description of the invention when taken in
conjunction with the following drawings.
[0020] FIG. 1 is a front, upper perspective view of the submersible
craft according to the present invention, showing the entire craft.
A rider lies on the craft in the prone position.
[0021] FIG. 2 is a rear, upper perspective view of the craft shown
in FIG. 1, illustrating the entire craft.
[0022] FIG. 3 is a front, lower perspective view of the craft
illustrated in FIG. 1, showing the entire craft from below and
illustrating where the tow rope is attached.
[0023] FIG. 4 is a rear elevation view of the craft according to
the present invention showing the entire craft and illustrating how
each shaft from the hydrofoils passes through each arm guard.
[0024] FIG. 5 is a perspective view that illustrates the left
hydrofoil, shaft, handle and end cap in isolation.
[0025] FIG. 6 is a right side elevation view of the craft according
to the present invention that illustrates how the main body of the
craft remains horizontal when the rider deflects the hydrofoils
down in order to descend.
[0026] FIG. 7 is a right side elevation view similar to FIG. 6,
except showing how the main body of the craft pitches up when the
rider deflects the hydrofoils up in order to ascend.
DETAILED DESCRIPTION OF THE DRAWINGS
[0027] A first preferred embodiment of the towable underwater craft
10 of the present invention is illustrated in FIGS. 1 through 5.
FIG. 1 shows the upper side of the craft. It will be appreciated
that a rider lies on the craft in the prone position with his or
her arms positioned in the left 13 and right 17 arm guards. The
rider's head and shoulders are positioned in and behind the
contoured leading edge 14. The main body 11 is defined by a
contoured central portion that is configured for accommodating a
rider's upper torso, a leading edge 14 and a pair of arm guards,
namely, a left arm guard 13 and a right arm guard 17. The left 12
and right 16 hydrofoils are located on their respective sides of
the craft and butt up against the left 13 and right 17 arm guards.
The tow rope 15 is attached to a powered water craft at one end
(not shown) and attached to the craft on the other end.
[0028] As detailed herein, the craft 10 defines a platform on which
the rider lies in a prone position. The craft has a leading edge
identified generally with reference number 52, and a trailing edge
given reference number 54. When a rider is lying prone on craft 10,
the trailing edge 52 of craft 10 is positioned near the rider's
stomach area--the position of the trailing edge 52 relative to the
rider's body depending of course upon the height of the rider. For
ease of reference, relative directional terms used herein are used
with reference to the horizontal plane defined by the water's
surface. Thus, "upper" refers to the direction toward the surface
of the water when the craft 10 is submerged; "lower" would thus
refer to the opposite direction. "Forward" identifies the direction
in which the craft is normally towed, and rearward is thus the
opposite direction. The "leading edge" of craft 10 is that edge of
the craft at the forward end that is presented to the water as the
craft is towed, and the trailing edge is the edge at the rear of
the craft.
[0029] With reference to FIGS. 2 and 3, the contour of the main
body 11 is visible in as well as the opening of the left 13 and
right 17 arm guards. The main body 11, left 13 and right 17 arm
guards, the contoured leading edge 14 and the fin 20 are all one
continuous piece constructed of a foam core and fiber reinforced
polymer exterior. The fin follows the longitudinal centerline CL
through the main body. The left 12 and right 16 hydrofoils are each
an additional part also constructed of foam and fiber-reinforced
polymer. The left 13 and right 17 arm guards are fully contoured
around the rider's hands and forearms providing protection from
oncoming debris and further reducing the drag on the craft |10|.
FIG. 3 shows the under side of the craft. Specifically the fin 20,
the left 18 and right 19 forked tow rope and the right 21 and left
22 end cap. In addition, the main body 11 attachment point
locations of the left 18 and right 19 forked tow ropes are shown.
They are attached via two eye bolts 60, 62 that each protrude
through the inside wall their respective left 13 and right 17 arm
guards The center of pressure 55 is the point on a body where the
sum total of the hydrodynamic pressure field acts, causing a force
and no moment about that point.
[0030] FIG. 4 shows the craft from the rear and illustrates how the
left 12 and right 16 hydrofoils attached to the left 13 and right
17 arm guards of the main body. The left 24 and right 26 shafts are
coaxial and protrude through holes on both sides of the left 13 and
right 17 arm guards. The shafts 25 and 26 define a shaft axis. The
right 21 and left 22 end caps are welded to the left 24 and right
26 shafts so that the shafts are pivotally journaled to the main
body. The right 21 and left 22 end caps and the left 24 and right
26 shafts are constructed of a stainless steel or other metals that
have a coating to protect against rusting and corrosion. The left
23 and right 25 handles are made of a rubber material and slides
over the left 24 and right 26 shafts to improve grip. Those of
ordinary skill in the art will appreciate that there are numerous
equivalent structures that may be used to pivotally attach the
shafts to the main body.
[0031] FIG. 5 shows the left hydrofoil 12, left shaft 24, left
handle 23 and the left end cap 22 with the rest of the craft
hidden. Both the left 24 and right 26 shafts extend into their
respective left 12 and right 16 hydrofoils and are bonded so that
the hydrofoils cannot rotate relative to the shafts.
Operation of Craft 10
[0032] The manner of using the towable under water craft is similar
to the use of current towable water sport devices such as a
wakeboard or water skis in that it is to be towed behind a powered
water craft by the use of the tow rope 15. It differs in that, upon
the rider's discretion the craft can submerge below the surface
while maintaining a significant amount of control in both depth and
roll. This control comes for the left 12 and right 16 hydrofoils
that are rigidly attached to the left 24 and right 26 shafts. The
left 24 and right 26 shafts pivot in the left 13 and right 17 arm
guards making the pitch of the left 12 and right 16 hydrofoils
movable simply by rotating the left 23 and right 25 handles. Pitch
stability comes from the location of the center of pressure 55. The
center of pressure 55 must be located behind the point of pitch
rotation, or the point where the left 18 and right 19 forked tow
ropes attach to the craft 10 at eye bolts 60 and 62. With the
center of pressure behind the point of pitch rotation, the craft 10
will naturally travel in the horizontal position.
[0033] FIG. 1 illustrates the purpose of the contoured leading edge
14 and the left 13 and right 17 arm guards. With a rider lying on
the main body, the contoured leading edge 14 and the left 13 and
right 17 arm guards help deflect the oncoming water around the
rider to minimize the drag felt and to protect the rider from
obstacles and debris. They also reduce the overall drag on the
craft resulting in higher speeds and more maneuverability.
[0034] FIG. 6 shows the craft from the right side and illustrates
how it descends. The craft descends by simply rotating both left 23
and right 25 handles downwards causing their respective left 12 and
right 16 hydrofoils to pitch down.
[0035] FIG. 7 shows how the craft ascends. Similarly, the craft
ascends by simply rotating both left 23 and right 25 handles
upwards. However, for safety reasons it has the ability to ascend
much quicker than it can descend. This is illustrated in FIG. 7 and
is caused by the location of the attachment points of the left 18
and right 19 forked tow ropes being well behind the left 12 and
right 16 hydrofoils. The location of attachment of the left 18 and
right 19 forked tow ropes to the craft 10 is also the point the
craft pitches about. Because this point is well behind the left 12
and right 16 hydrofoils, the entire craft pitches upwards when the
left 12 and right 16 hydrofoils are pitched up making for a quicker
ascent. As an additional built-in safety feature, the craft will
also ascend with no control input at all. The left 12 and right 16
hydrofoils produce no lift when in their natural position, or with
no control input. At this point the inherent buoyancy of the craft
from the composite construction takes over and raises the craft to
the surface. Roll is controlled simply by rotating the left 23 and
right 25 handles in opposite directions causing the left 12 and
right 16 hydrofoils to pitch in opposite directions.
[0036] While the present invention has been described in terms of a
preferred embodiment, it will be appreciated by one of ordinary
skill that the spirit and scope of the invention is not limited to
those embodiments, but extend to the various modifications and
equivalents as defined in the appended claims.
* * * * *