U.S. patent application number 12/457188 was filed with the patent office on 2010-07-15 for self-adjusting wave break.
Invention is credited to Dave David Matthew Wilson.
Application Number | 20100178109 12/457188 |
Document ID | / |
Family ID | 42315991 |
Filed Date | 2010-07-15 |
United States Patent
Application |
20100178109 |
Kind Code |
A1 |
Wilson; Dave David Matthew |
July 15, 2010 |
Self-adjusting wave break
Abstract
The wave break has an elongated shape and three wave-breaking
surfaces mounted thereon and forming an elongated triangular
configuration. The wave break has a lazy side on its forward edge,
such that the force of the wave tilts it about the forward edge to
increase a projection of its wave-breaking surfaces against the
incoming wave. Because of the lazy forward side of the wave break,
the leading stringer dive into each wave without deviating
substantially from a horizontal plane. The trailing side of the
wave break is subject to the lifting forces of each wave and
therefore, the trailing side tilts upward and downward in use. The
trailing side tilts upward and downward about the leading stringer
to rotate the wave-breaking barriers into a more or less
perpendicular alignment relative to the wave movement, for breaking
the wave more effectively.
Inventors: |
Wilson; Dave David Matthew;
(Bear River, CA) |
Correspondence
Address: |
MARIO D. THERIAULT
812 HWY. 101 NASONWORTH
FREDERICTON
NB
E3C 2B5
CA
|
Family ID: |
42315991 |
Appl. No.: |
12/457188 |
Filed: |
June 3, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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61193930 |
Jan 9, 2009 |
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Current U.S.
Class: |
405/27 |
Current CPC
Class: |
E02B 3/062 20130101 |
Class at
Publication: |
405/27 |
International
Class: |
E02B 3/04 20060101
E02B003/04 |
Claims
1. A wave break having an elongated structure and a triangular
cross section; said triangular cross-section having a right-angle
triangular shape comprising a right-angle side and an acute-angle
side; said right angle triangular shape being defined by three
stringers comprising a leading stringer at said acute-angle side;
said elongated structure also having three barrier surfaces
extending there along and each of said barrier surfaces comprising
a plurality of pipe members spaced apart from each other and
extending at right angle between two of said stringers; each of
said stringers and pipe members having a sealed hollow
configuration and forming a floating vessel; said leading stringer
having substantially no buoyancy.
2. The wave break as claimed in claim 1, wherein said tree
stringers comprising a trailing stringer and an upper stringer,
along said right angle side of said right-angle triangular shape,
and said three barrier surfaces comprising a first barrier surface
extending between said leading stringers and said upper stringer; a
second barrier surface extending between said leading stringer and
said trailing stringer; and a third barrier surface extending
between said trailing stringer and said upper stringer.
3. The wave break as claimed in claim 2, wherein said trailing
stringer; said upper stringer; said first barrier; said second
barrier and said third barrier are made of hollow pipes that are
sealed at ends.
4. The waver break as claimed in claim 3, wherein said trailing
stringer; said upper stringer; said first barrier; said second
barrier and said third barrier are made of hollow pipes that have a
same diameter.
5. The wave break as claimed in claim 4, wherein said hollow pipes
in said first barrier surface; said second barrier surface and said
third barrier surface have fins on the sides thereof.
6. The wave break as claimed in claim 5, wherein said pipes in each
of said first barrier surface; said second barrier surface and said
third barrier surface, are paced apart a distance equivalent to
twice one diameter of said pipe.
7. The wave break as claimed in claim 6, wherein said pipes in one
of said first barrier surface; said second barrier surface and said
third barrier surface, are spaced apart one diameter respectively
from said pipes in another one of said first barrier surface; said
second barrier surface and said third barrier surface.
8. The wave break as claimed in claim 5, wherein said fins have a
width corresponding to one radius of said pipe.
9. The wave break as claimed in claim 8, wherein said fins are
inclined an angle between 0.degree. and 60.degree. from a
respective barrier surface.
10. The wave break as claimed in claim 3, wherein said trailing
stringer has a larger diameter than said leading stringer.
11. A wave break installed at an installation site, said wave break
having an elongated structure and a triangular cross section; said
triangular cross-section having a right-angle triangular shape
comprising a right-angle side and an acute-angle side, and a
mooring line attached thereto; said right angle triangular shape
being defined by three stringers comprising a leading stringer at
said acute-angle side; said elongated structure also having three
barrier surfaces extending there along and each of said barrier
surfaces comprising a plurality of pipe members spaced apart from
each other and extending at right angle between two of said
stringers; each of said stringers and pipe members having a sealed
hollow configuration and forming a floating vessel; said leading
stringer having substantially no buoyancy; said mooring line being
attached to said leading stringer; and said elongated structure
forming an arc having a convex side facing incoming wave at said
installation site.
12. The wave break as claimed in claim 11, wherein said acute-angle
side facing said incoming wave at said installation site.
13. The wave break as claimed in claim 12, wherein said tree
stringers comprising a trailing stringer and an upper stringer,
along said right angle side of said right-angle triangular shape,
and said three barrier surfaces comprising a first barrier surface
extending between said leading stringers and said upper stringer; a
second barrier surface extending between said leading stringer and
said trailing stringer; and a third barrier surface extending
between said trailing stringer and said upper stringer; and said
pipe members in said third barrier surface have a length of one
quarter of a period in typical waves found at said installation
site.
14. The wave break as claimed in claim 13, wherein said pipe
members in said second barrier surface have a length equivalent to
a height of typical waves found at said installation site.
15. The wave break as claimed in claim 14, wherein said leading
stringer and said upper stringer have a same diameter and said
trailing stringer has a larger diameter than said same
diameter.
16. The wave break as claimed in claim 15, wherein said same
diameter is 12 to 16 inches.
17. The wave break as claimed in claim 15, wherein said elongated
structure is made of joined segments each having a length of 20
feet.
18. The wave break as claimed in claim 17 further having a mooring
line attached to said leading stringer.
19. The wave break as claimed in claim 18, wherein said mooring
line is a slack mooring cable.
20. The wave break as claimed in claim 18, wherein said mooring
line comprises a heavy mooring chain causing said leading stringer
to sink relative to said trailing stringer.
Description
[0001] This application claims the benefit of U.S. Provisional
Application No. 61/193,930 filed Jan. 9, 2009.
FIELD OF THE INVENTION
[0002] This invention pertains to floating breakwaters or break
walls installed along harbours to protect vessels moored in these
harbours, and most particularly, it pertains to self-adjusting wave
breaks that automatically expose a larger wave-breaking surface
when floating in larger waves. These break walls are also installed
to prevent soil erosion along shore lines.
BACKGROUND OF THE INVENTION
[0003] The efficiency of a breakwater depends on its ability to
break up and scatter waves without being lifted by these waves.
This efficacy is difficult to achieve with a floating breakwater
having a slack mooring line, in particular, because upward forces
from the breakwater's buoyancy tend to push the breakwater at the
surface of the wave.
[0004] In the past, at least two attempts have been made to design
a floating wave break that is intended to plunge through a wave to
cut through and to disperse the crest of the wave. These prior art
wave breaks have no similarities with the wave break according to
the present invention, but the prior art documents describing these
older breakwaters are nonetheless cited herein below simply to
illustrate the environment in which the present invention will be
described.
[0005] U.S. Pat. No. 335,032 issued to L. W. Leeds on Jan. 26, 1886
discloses different wave breaks, each having a floating structure
and a wedge-like horizontal plow-bar, referred to as a cut-water,
projecting forward from the floating structure. The cut-water bar
penetrates the waves along a horizontal plane to break the force of
the waves before they reach the floating structure.
[0006] U.S. Pat. No. 3,952,521 issued to J. M. Potter on Apr. 27,
1976 discloses an elongated triangular structure supported on two
tubular floats. The floats have airfoil-like fins on their sides to
cause the floats to dig into the forward side of a wave and to
retain the wave break against the lifting forces of the wave so
that the wave break can pass through the crest of the wave.
[0007] Although the devices of the prior art deserve undeniable
merits, there is a need for a more efficient floating wave break
which can be easily moved and anchored with slack mooring
lines.
SUMMARY OF THE INVENTION
[0008] In the present invention, there is provided a wave break
that has an elongated shape and three wave-breaking surfaces
mounted thereon to form an elongated triangular configuration. The
wave break has a lazy side on its forward edge, such that the force
of the wave tilts it about the forward edge to increase a
projection of its wave breaking surfaces against the incoming
wave.
[0009] More specifically, in one aspect of the present invention
there is provided a wave break that has an elongated structure with
a triangular cross-section. The triangular cross-section has the
shape of a right-angle triangle with a right-angle side and an
acute-angle side. The right angle shape is defined by three
elongated stringers from which a leading stringer is at the
acute-angle side.
[0010] The elongated structure also has three wave barrier surfaces
extending there along. Each of these wave barrier surfaces is made
of a plurality of pipe members spaced apart from each other and
extending at right angle between two of the afore-mentioned
stringers.
[0011] Each of the stringers on the right-angled side, and each
pipe member has a sealed hollow configuration forming a floating
vessel. The leading stringer has added weight therein or open ends
such that a buoyancy thereof is substantially nil. The wave break
also has a mooring line attached to the leading stringer.
[0012] Because of the lazy forward side of the wave break, the
leading stringer dive into each wave without deviating
substantially from a horizontal plane. The trailing side of the
wave break is subject to the lifting forces of each wave and
therefore, the trailing side tilts upward and downward in use. The
trailing side tilts upward and downward about the leading stringer
to rotate the wave breaking barriers of the wave break into a more
or less perpendicular alignment relative to the wave movement, for
breaking the wave more effectively.
[0013] Also, the wave break according to the present invention is
relatively light and easy to transport and to install as compared
to other breakwaters available commercially.
[0014] This brief summary has been provided so that the nature of
the invention may be understood quickly. A more complete
understanding of the invention can be obtained by reference to the
following detailed description of the preferred embodiment thereof
in connection with the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] A preferred embodiment of the present invention is
illustrated in the accompanying drawings, in which like numerals
denote like parts throughout the several views, and in which:
[0016] FIG. 1 is a perspective view of a breakwater made with
self-adjusting wave break segments according to a preferred
embodiment of the present invention, joined end-to-end;
[0017] FIG. 2 is an end view of a preferred wave break segment
floating along the hollow of a wave or on calm waters;
[0018] FIG. 3 is an end view of the preferred wave break segment
floating through a wave;
[0019] FIG. 4 is a reference illustration showing the period and
amplitude of a wave;
[0020] FIG. 5 is an enlarged end view of the preferred wave break
segment illustrated in FIGS. 2 and 3;
[0021] FIG. 6 is a cross section view of one pipe member in the
preferred wave break segment as seen along line 6-6 in FIG. 5;
[0022] FIG. 7 is a partial oblique view of the wave break segment
as seen along line 7-7 in FIG. 5;
[0023] FIG. 8 is a cross-section plan view of the preferred wave
break segment as seen along line 8-8 in FIG. 5;
[0024] FIG. 9 is an enlarged view of the end of a wave break
showing optional structural variations that are within the scope of
the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0025] The expression "wave break" is used by seamen to describe a
wave breaking structure protecting a harbour, and therefore it is
also used herein for convenience to describe the wave break
structure according to the present invention.
[0026] Referring firstly to FIG. 1, the preferred wave break 20
consists mainly of an elongated openwork structure having a
triangular cross-section. The openwork structure is made of hollow
pipes. The hollow pipes are preferably made of plastic, but can
also be made of metal tubes having a relatively thin wall. The
preferred wave break 20 has a transportable length and is referred
to herein interchangeably as a wave break or a wave break segment.
These segments are joined to each other, at joints 22, to form
breakwaters 24 having lengths of 20 feet or more, for example.
[0027] These breakwaters 24 are anchored to the seabed by slack
mooring cables 26 or chains. The expression "slack mooring cables
or chains" is used here to describe a mooring system that allows
the wave break 20 to rise and fall with the tides. It will be
appreciated that the tension of the mooring lines can be adjusted
to retain the leading stringer within a desired vertical
displacement, according to wave heights and tides at the
installation site.
[0028] These breakwaters 24 are installed in straight lines, or
most preferably, these breakwaters are installed to form an arc
having a convex side facing the incoming waves, as illustrated in
FIG. 1.
[0029] Referring now to FIGS. 2 and 3, the preferred wave break 20
is made of three open planar frameworks connected to each other by
three parallel longitudinal stringers, in a right-angle triangular
configuration. In use, the acute-angle side of the wave break 20
faces against the movement 28 of the waves as illustrated.
[0030] The stringer on the leading edge of the wave break 20 is
referred to as the leading stringer 30. In use, a mooring line 24
is attached to the leading stringer 30.
[0031] The-stringer on the trailing edge is referred to as the
trailing stringer 32, and the stringer on the upper edge is
referred to as the upper stringer 34. The open framework extending
between the leading stringer 30 and the upper stringer 34 is
referred to as the first barrier surface 40. The open framework
lying between the upper stringer 34 and the trailing stringer 32 is
referred to as the second barrier surface 42, and the open
framework lying between the leading stringer 30 and the trailing
stringer 32 is referred to as the third barrier surface 44.
[0032] The preferred wave break 20 is made of cylindrical pipe
members that are sealed at ends and at all joints so that they
constitute hollow floating structures. The leading stringer 30 is
weighted down with concrete 46 or other heavy material so that the
wave break 20 tilts forward in calm water. The leading stringer 30
is weighted down or its ends are left open, so that its buoyancy is
substantially nil and so that it remains submerged below the water
surface, as illustrated in FIG. 2 in calm waters. Using seamen
language, the preferred wave break 20 has a lazy forward side,
which does not react or that is slow to react to buoyant
forces.
[0033] It should be understood that the weighing of the leading
stringer 30 can also be done partially or entirely by using heavy
mooring chains 24 instead of cables.
[0034] Because of the structural features of the preferred wave
break 20, the leading stringer 30 plunges into the waves 60 in
rough waters, as illustrated in FIG. 3. The buoyancy forces on the
third barrier surface 44 and on the trailing stringer 32 causes the
wave break 20 to tilt forward when traversing a wave 60, thereby
reducing the angle `A` as illustrated in FIGS. 2 and 3. It will be
appreciated that the reduction of the angle `A` is in direct
relationship with the height of the waves 60, because it varies
directly with the portion of the wave break 20 that is submerged
when a wave pass through the wave break 20.
[0035] The variation in the angle `A` is due to a rotation of the
wave break 20 about the leading stringer 30 in a direction `B`. A
rotation of the wave break 20 in the direction `B` causes the
leading stringer 30 to dive through an incoming wave 60 and causes
the first barrier surface 40 to move toward a perpendicular
alignment relative to the movement of the wave 60. Similarly, the
tilting of the wave break 20 in the direction `B` causes the second
and third barrier surfaces 42, 44 to form converging fence-like
surfaces across the movement of the wave 60, as illustrated in FIG.
3.
[0036] As it can be understood, all three barrier surfaces 40, 42
and 44 cooperate together to break up the waves 60 in two cascading
steps. A first step consists of passing the wave through a
quasi-vertical barrier to change the direction of the flow a first
time, and the second step consists of passing the waves through the
converging fence-like surfaces, for changing the direction of the
wave a second and third times.
[0037] After the passage of a wave 60 through the wave break 20,
the wave break 20 returns back to its initial attitude as
illustrated in FIG. 2. The buoyancy forces on the preferred wave
break 20 cause the wave break 20 to tilt back and forth and to
self-adjust to the height of the wave entering into its barrier
surfaces 40, 42 and 44.
[0038] In high waves, the first barrier surface 40 rotates toward a
vertical alignment, thereby presenting a maximum degree of
resistance to the incoming wave 60. Because of the triangular
cross-section of the wave break 20, the buoyancy forces on the
second and third barrier surfaces 42, 44 generate a torque about
the leading stringer 30, to force the first barrier surface 40 to
move toward a vertical alignment. This torque increases with the
degree of immersion of the wave break 20. Similarly, this torque
causes the second and third barrier surfaces 42, 44 to move toward
a funnel-like alignment where both surfaces converge together and
contribute substantially equally to the breaking-up of the wave
60.
[0039] The expression "self-adjusting" in the description of the
present invention comes from the fact that the wave break 20 tilts
back and forth about the leading stringer 30, to increase or to
decrease the aggressiveness with which the wave-breaking surfaces
thereof are oriented in response to the height of a wave being
penetrated.
[0040] Referring now to FIGS. 4-9, additional structural details of
the preferred wave break 20 will be described.
[0041] In a preferred embodiment, each barrier surfaces 40, 42, 44
is made of spaced-apart parallel pipe members each having a same
diameter as the longitudinal stringers 30, 32, 34. The pipe members
forming the first surface barrier 40 are labelled as pipe members
70. The pipe members labelled as 72 form the second surface barrier
42, and the pipe members labelled as 74 form the third surface
barrier 44.
[0042] The preferred length of the pipe members 74 forming the
third surface barrier 44 or the base of the wave break 20 is
preferably one quarter (1/4) of the period `P` of typical waves
found at the location where the wave break 20 will be installed.
The length of the pipe members 72 forming the second surface
barrier 42 or the height of the wave break 20 is preferably the
same dimension as a typical wave height `H` found at the location
where the wave break will be installed.
[0043] Typical dimensions for the length of the pipe members 72, 74
and 70 are six, eight and ten feet respectively, and the diameter
of each pipe member is about twelve to sixteen inches. The
dimensions of the pipe members in the preferred wave break 20 are
adjusted according to the severity of the conditions where the wave
break will be installed. These dimensions are adjusted according to
factors such a wave height, wave period, water current and the
length of the breakwater 24 to be formed.
[0044] Each of the barrier pipe members 70, 72 and 74 has fins 76
on its sides as illustrated in FIG. 6. The purpose of these fins in
the first barrier surface 40 is to deflect water sideways and
against one of the pipe members 72, 74 in the second and third
barrier surfaces 42, 44. The purpose of the fins 76 on the pipe
members 72, 74 is to deflect water sideways and create turbulence
behind the wave break 20 to further break up the waves 60 after
these waves have passed through the wave break 20.
[0045] The preferred spacing `S` of pipe members 70, 72 or 74 along
a same barrier surface 40, 42 or 44 is about at least twice as much
as the outside diameter of one pipe member. The preferred spacing
of pipe members in one barrier surface from the pipe members in an
adjacent barrier surface is about the same as the diameter of one
pipe member, such that the pipe members in one surface barrier is
offset the distance of one pipe member from the pipe members in an
adjacent barrier surface.
[0046] The width of the fins 76 on each of the pipe members 70, 72,
and 74, is equal to or less than the radius on one pipe member,
such that the effective width `W` of each pipe member, as shown in
FIG. 6, is about twice or slightly less than twice the diameter of
one pipe member. The effective width `W` of each pipe member is
also determined taking into account the water current present at
the location where the wave break 20 will be installed. The
effective width `W` is selected so that the drag created on the
wave break 20 by the water current does not prevent an effective
tilting of the wave break 20 as described herein.
[0047] Similarly, the inclination `C` of the fins 76 can vary from
0.degree. to 60.degree. and this angle is also determined according
to the severity of the conditions at the installation site.
[0048] Referring now to FIG. 9, this illustration will be used to
explain two structural variations which should be considered to be
withing the scope of the present invention. As mentioned before,
the stringers 32 and 34 on the right-angle side of the wave break
20 have closed ends so that they act as floating vessels. In order
to further increase the buoyancy of the wave break 20, and to
further promote a rotation of the wave break 20 about the leading
stringer 30, the trailing stringer may have a larger diameter than
the other stringers, as illustrated by label 32' in FIG. 9. Also,
as mentioned before, the leading stringer 30 may have open ends as
indicated by label 30', so that its buoyancy is substantially
nil.
[0049] The dotted lines in FIGS. 7, 8 and 9 indicate a repetition
of the pipe member arrangements over the full length of a wave
break segment 20.
* * * * *