U.S. patent application number 12/900097 was filed with the patent office on 2012-04-12 for simplified wave energy device without one-way clutches.
Invention is credited to Dennis John Gray.
Application Number | 20120087732 12/900097 |
Document ID | / |
Family ID | 45925262 |
Filed Date | 2012-04-12 |
United States Patent
Application |
20120087732 |
Kind Code |
A1 |
Gray; Dennis John |
April 12, 2012 |
Simplified Wave Energy Device Without One-way Clutches
Abstract
This invention is a greatly simplified device for transforming
the energy of water waves into useable energy. The invention is a
device for transforming the energy of water waves into useable
energy comprising two or more buoys or buoys, and structural
members connecting buoys, whereby motions of buoys relative to one
another generates torque, and a means for transferring torque to
one or more generators, and a means by which to enable all
generator currents to flow in a single beneficial direction. Novel
systems for interconnecting such devices are also described
herein.
Inventors: |
Gray; Dennis John; (Spring,
TX) |
Family ID: |
45925262 |
Appl. No.: |
12/900097 |
Filed: |
October 7, 2010 |
Current U.S.
Class: |
405/76 |
Current CPC
Class: |
Y02E 10/38 20130101;
E02B 9/08 20130101; Y02E 10/30 20130101; F03B 13/20 20130101 |
Class at
Publication: |
405/76 |
International
Class: |
E02B 9/08 20060101
E02B009/08 |
Claims
1. A device for transforming the energy of water waves into useable
energy comprising two or more buoys, and structural members
connecting said buoys, at least two hinge points, whereby motions
of said buoys relative to one another generates torque, one or more
shafts or other means by which to transfer torque connected to one
or more generators, and a means by which to ensure that one or more
generator output currents flow in a single useful direction despite
the reversing of generator rotation.
2. The device of claim 1 with one or more slip clutches or other
means by which to automatically disengage torque at appropriate
times.
3. The device of claim 1 with a means by which to control
electrical load or otherwise control the flexibility of the device
at hinge points.
4. The device of claim 1 whereby one or more transmissions or
gearboxes are added which increase the speed of one or more
generators.
5. The device of claim 1 whereby one or more structural members are
made automatically adjustable in length resulting in improved
energy production.
6. The device of claim 1 whereby an interconnect system is
included.
7. The device of claim 1 whereby one or more buoys are sufficiently
weighted resulting in useful torque during both upward and downward
buoy motions.
8. The device of claim 1 with a means by which to temporarily
submerge the device when environmental conditions are deemed too
onerous.
9. A device for transforming the energy of water waves into useable
energy comprising two or more buoys, and structural members
connecting said buoys, at least three hinge points, whereby motions
of said buoys relative to one another generates torque, one or more
shafts or other means by which to transfer torque connected to one
or more generators, a means by which to ensure that one or more
generator output currents flow in a single useful direction despite
the reversing of generator rotation, and a means by which to
control electrical load or otherwise control the flexibility of the
device at hinge points.
10. The device of claim 9 with one or more slip clutches or other
means by which to automatically disengage torque at appropriate
times.
11. The device of claim 9 whereby one or more transmissions or
gearboxes are added which significantly increase the speed of one
or more generators.
12. The device of claim 9 whereby one or more structural members
are made automatically adjustable in length resulting in improved
energy production.
13. The device of claim 9 whereby an interconnect system is
included.
14. The device of claim 9 whereby one or more buoys are
sufficiently weighted resulting in useful torque during both upward
and downward buoy motions.
15. The device of claim 9 with a means by which to temporarily
submerge the device when environmental conditions are deemed too
onerous.
16. A device for transforming the energy of water waves into
useable energy comprising two or more buoys, and structural members
connecting said buoys, three or more hinge points that are elevated
above mean water level, whereby motions of said buoys relative to
one another generates torque, one or more shafts or other means by
which to transfer torque connected to one or more generators, a
means by which to protect one or more shaft locations from water
penetration, a means by which to ensure that one or more generator
output currents flow in a single useful direction despite the
reversing of generator rotation, and a means by which to control
electrical load or otherwise control the flexibility of the device
at hinge points.
17. The device of claim 16 with one or more slip clutches or other
means by which to automatically disengage torque at appropriate
times.
18. The device of claim 16 whereby one or more transmissions or
gearboxes are added which significantly increase the speed of one
or more generators.
19. The device of claim 16 whereby one or more structural members
are made automatically adjustable in length resulting in improved
energy production.
20. The device of claim 16 whereby an interconnect system is
included.
21. The device of claim 16 whereby one or more buoys are
sufficiently weighted resulting in useful torque during both upward
and downward buoy motions.
22. The device of claim 16 with a means by which to temporarily
submerge the device when environmental conditions are deemed too
onerous.
Description
CROSS-REFERENCES TO MOST RELATED APPLICATIONS
TABLE-US-00001 [0001] Patent or Application # Title 12/175,196
Energy Transformation Device 7,199,481 Wave energy conversion
system 6,857,266 Wave energy converter 6,812,588 Wave energy
converter 6,772,592 Float dependent wave energy device 6,791,205
Reciprocating generator wave power buoy 6,765,307 Wave energy
converter (WEC) 6,392,314 Wave energy converter 6,226,989 Wave
energy converter 5,027,000 Method and apparatus for generating
electricity using wave energy 4,412,417 Wave energy converter
4,359,868 Ocean wave energy converter 4,345,434 Sea and ocean wave
energy converter 4,258,269 Wave power generator 4,077,213 Wave
driven generator 20030091393 Wave power machine 20030110767 Method
and installation of power generation by ocean wave 20070164569
Ocean energy harvesting system 20070164568 Wave energy recovery
system 20070132246 Wave energy conversion system 20050099010 Wave
energy conversion system 20070180823 Wave energy device
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH &
DEVELOPMENT
[0002] Not Applicable. No others have rights to this patent.
BACKGROUND OF THE INVENTION
[0003] Populations grow exponentially, demand for energy is
escalating, and political tensions over hydrocarbons are increasing
to say the least. In light of these issues the U.S. Department of
Energy continues to place renewable energies as a focal point to
their program.
[0004] When one looks across an open ocean and views the large
rolling waves the energy is glaringly obvious. Winds travel for
hundreds of miles and beautifully store and compact their energy
into waves. The magnitude of energy and density of energy in ocean
waves is fairly easy to comprehend. After all, only waves can pitch
and roll ships weighing thousands of tons.
[0005] To be cost-effective and viable, a wave energy device must
be very simple. It must also be strong to survive punishing ocean
environments. Last but not least, it must avoid sophisticated
components and have any critical components protected from the
harsh oceanic environment. Simplicity in design ensures low capital
investment, low operating costs, low maintenance costs, and low
energy production costs. Ideally, a wave energy system should be
complete and demonstrate interconnectivity. An individual device
should not require individual mooring systems and individual subsea
electric cables to shore. Devices should float on the water surface
to extract maximum wave energy and either be capable of
withstanding storm events, be towed away when the largest of storms
arise, or temporarily sink below water level until storms pass.
[0006] Upon review of existing patents one will find that most have
addressed only a few of the challenging design requirements
mentioned above. Many wave energy patents that have avoided or
eliminated the use of one-way clutches have not sufficiently
described how they work and how they would actually be built. A
patent specification must enable any person skilled in the art or
science to which the invention pertains to make and use the same".
Without sufficient descriptions a patent can be deemed invalid.
Without addressing all of the challenging design requirements an
wave energy device cannot cost-effectively and reliably deliver
power. The novel invention presented herein overcomes the above
challenges. Particular features not found in prior patent
applications make this invention fully viable, useful, and
beneficial.
BRIEF SUMMARY OF THE INVENTION
[0007] The purpose of this invention is to efficiently and cost
effectively transform water wave energy into useful electrical
energy with little or no environmental impact. There are numerous
advantages of this particular invention in comparison with prior
art.
[0008] Maximum available wave power, not partial available power,
is extracted by this device and it is extracted on both up and down
strokes. Torque arms, acting as levers, add mechanical advantage
for power output. The refined design ensures that capital costs
will be very low and reliability will be extremely high. Critical
components are 100% protected from oceanic spray keeping
maintenance costs negligible. No reversing gears are utilized and
slightly higher gearing ratios are used for significant benefits.
The efficiency losses associated with reducing gears is completely
eliminated. Reversing gear systems have generators that spin too
slowly and are not of large enough diameter. Thus, these generators
become too heavy and expensive. Heavy generators inhibit a wave
energy device from harnessing energy because the device cannot
properly maintain rhythm or resonance with wave motions. Standard
gearboxes can and should be utilized instead of reversing gear
systems and such gearboxes can come from many suppliers at fairly
low prices.
[0009] The use of one-way clutches in wave energy devices presents
additional efficiency losses and higher costs. It is better to
simply reduce the mass moment of inertia of the gearing and
generator so that both gearbox and generator can spin in both
directions as waves rise and fall. Multiple hinge points make the
device stronger in rough seas and/or quartering seas, enables
system redundancy, and enables gearboxes and generators with
smaller diameters and lower mass moments of inertia. In combination
with reduced mass moments of inertia these wave energy devices
should have equipment that accommodates the changing direction of a
generator's current flow as waves change from up to down stroke. In
essence, sensors would recognize when waves change from up to down
motion or when a generator's current direction changes. At these
moments the electrical paths would be switched or flip-flopped so
that a generator's current is ultimately heading in the preferred
direction. Modern electrical equipment can have milli-second
response times. In one embodiment, as shown in FIG. 3, the
electrical lines are switched at the changing of wave strokes so
that the outflow paths remain unchanged.
[0010] Buoys can be flooded and the device temporarily submerged
below water level. A system for interconnecting energy
transformation devices is included herein. Interconnectivity
creates a truly complete system that eliminates the need for many
individual mooring lines, eliminates a considerable amount of
electrical cable, and it allows many of units to be towed via a
single tugboat. Towing of many units is desirable since many units
could potentially be installed or removed all at once. Mass towing
also enables production-line maintenance at shoreline.
Assembly-line maintenance at shoreline is far less expensive and
safer than maintenance or repair performed offshore. In essence,
while many other arrays are generating power just one array at a
time can be brought in for service.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0011] FIG. 1 is a plan and side view of a preferred embodiment of
the invention where reversing gears and one-way clutches have been
eliminated from the design.
[0012] FIG. 2 is a plan and side view of a preferred embodiment of
the invention where reversing gears, one-way clutches and gearboxes
have been eliminated from the design.
[0013] FIG. 3 is a drawing of a switch that could accommodate the
changing of wave up/down stroke.
[0014] FIG. 4 is an isometric view of a two buoy version of the
device with many hinge points.
[0015] FIG. 5 is a plan view of many devices connected together
with an interconnectivity and mooring system.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0016] The invention can be designed and scaled for any size waves.
A preferred embodiment would primarily be constructed of steel or
other suitable marine materials. Components of the device include
two or more buoys (1) connected by torque arms (2) whereby a
pivoting motion is permitted at hinge points (3) that have bushing
or bearings. The buoy movements generate torque which drive one or
more gearboxes (4) which in turns drives one or more generators (5)
at higher speeds for electrical output.
[0017] The complex transmission system described in U.S. Pat. No.
7,315,092 is too customized and expensive, reversing gears are not
necessary, and reversing gears present unnecessary efficiency
losses. Most importantly, the electrical load, or the amount a wave
energy device is trying to power, can be controlled such that the
moment of inertia of gearboxes and generators can be consumed
before a wave reverses direction. For example, electrical load can
be electronically increased just as a wave turns from going up to
going downward which would stop the gearboxes and generators. Thus,
one-way clutches are not necessary. When a gearbox with dual output
shafts is used there can be two generators which as shown at the
bottom of the device depicted in FIG. 1. These two generators are
labelled as generator (6) and generator (7). This dual generator
configuration can inherently reduce the mass moment of inertia of
the system since two generators with smaller diameters can have
less moment of inertia than one generator of larger size and
diameter. Another problem associated with the transmission system
described in U.S. Pat. No. 7,315,092 is that it does not permit a
high enough rotational speed for the generators to work
efficiently. As a result, the U.S. Pat. No. 7,315,092 has
generators that are too large, too expensive, too heavy, and they
therefore inhibit the device's ability to move with the waves and
generate power. This is why gearboxes with higher gearing ratios
have been used in this invention.
[0018] Although it is desirable that wave energy devices be
relatively invisible on the horizon, corners/edges of arrays (many
units linked together) will likely be marked with traditional
lighted buoys. This will ensure that they are visible from ships at
night and in fog.
[0019] All critical components are enclosed and protected since the
buoys (1) themselves function as protective shells. The only
exposed moving joints are the bushings/bearings (8) that are
properly designed for submersion in salt water. Common propeller
shafts of ships have very similar watertight bearings and seals. If
desired, and since the torque arms do not rotate in excessive
angles, a sleeve (9) can be installed to cover any
bushings/bearings from salt water contact. This invention
deliberately raises the elevation of the pivot points (10) to above
mean waterline. Propeller shaft seals are designed to be used fully
underwater but leakage is far less likely with the pivot points,
seals and sleeves/boots elevated above waterline. Universal joints
or flex joints (11) may be used to ensure that only pure torque
enters gearboxes. Nylatron, plastic, or other pad materials (12)
can be used at pivot points to ensure the torque arms do not rub or
contact the buoy.
[0020] In the preferred embodiment the buoys (1) are flattened but
in other embodiments the buoys could have a wide range of
volumetric shapes. Flattened buoys or buoys enable immediate
response to wave motions. Buoys are constructed of thick materials
or deliberately weighted in this embodiment such that they float at
about mid level. Weights could be made of concrete, other solid
materials, or liquid materials. Buoyancy provides an upward force
while weight provides a downward force, both of which generate
useful torque. As a result, both upward and downward buoy motions
result in torque that ultimately drives generators (5). Splitting
this torque relatively evenly, vs. twice the torque on just up or
down strokes, reduces the cost of the drive train (gearboxes,
generators, etc). Without thick buoy plating or weights (13) the
resistance of generators (5) and gears would likely cause buoys to
"stick" in an upward position upon the first wave crest. At a
minimum, the downward movement of buoys would likely be
delayed.
[0021] As mentioned previously, buoys are connected via torque arms
(2). Torque arms may have the capability of automatically extending
or retracting themselves via auto-lengthening mechanisms.
Auto-lengthening mechanisms can accommodate varying wavelengths as
sea conditions change on any given day. Arm length adjustability
increases energy production since distances between outer buoys can
better match wavelengths on a given day for optimized power output.
In a preferred embodiment, one wave energy device within a large
array could measure wave heights and wave periods. A computer
program could then estimate average wavelengths from the recorded
data and instruct all torque arms within that array to lengthen or
shorten accordingly. In the preferred embodiment, the
auto-lengthening mechanisms are actuated electromechanically but
they could also be actuated via hydraulics or other means.
Auto-lengthening mechanisms, like the primary bearings, can be
protected from saltwater contact by waterproof sleeves.
[0022] With wave movements the motion of one buoy relative to the
other buoy or buoys creates extremely high torque. Very high torque
is a result of the large displacement of a buoy (1) coupled with
the torque arm lengths whether the arms are long or short. The high
torque is next directly transferred via the torque arms (2) to a
shaft which rotates a gearbox (4). Note that gears, chains and
sprockets, or other means can serve to transfer torque to one or
more generators.
[0023] Similar to arrays of offshore wind turbines, electrical
processing equipment can take the electrical output of each
generator, process and combine it at a central electrical
processing station, and send it to shore via a single subsea cable,
batteries, compressed air, or other means. In a one embodiment a
central electrical processing station is enclosed within a
windowless room and located on a barge near the center of an array.
The windowless room could be climate controlled and dehumidified to
better protect the equipment within the electrical processing
station. Alternatively, the central electrical processing station
could be located in a subsea pod.
[0024] Components of energy transformation devices that are exposed
to the elements, which include buoys and torque arms, can be
structurally designed for storm and hurricane forces. Offshore oil
platforms have similar pontoons and tubulars that are designed for
such storms. Many torque arms can be used and they can be laterally
braced and/or trussed (14) as well as vertically braced and/or
trussed. In a preferred embodiment, if excessively large waves were
encountered, the gearbox could automatically disengage via a
clutch. Slip clutches (15) such as those constructed of spring
loaded frictional discs can be installed to ensure that gearboxes
and all remaining drive train machinery can never be over-loaded.
This disengagement feature permits wave energy devices to
accommodate excessively dynamic conditions without any damaging
effects to internal components.
[0025] In rough seas, wave energy devices would have a natural
tendency to collide with one another within their arrays. Note that
any point on an individual device will move through all six degrees
of translation and rotation within a wave cycle. Consequently,
there is no single point on an energy transformation device that
can be "grabbed" or "held" rigidly in an attempt to interconnect
them. FIG. 5 shows flexible interconnection lines (15) connected
between devices with mooring lines (16) and anchors (17) at the
ends of arrays to keeps lines taught and all devices from
contacting one another. Items 15, 16, and 17 together create an
interconnect system.
[0026] Wave energy devices of this type with just two hinge points,
as described in U.S. Pat. No. 7,315,092, are not likely to be
structurally strong enough to handle waves coming from diagonal
direction or "quartering seas" as this is sometimes called. Devices
with few hinge points typically have fewer gearboxes and generators
with much larger mass moments of inertia. Many torque arms and
hinge points are shown in FIG. 4. Many hinge points not only makes
the device stronger in rough seas but it enables many gearboxes and
generators, a lower total mass moment of inertia in the machinery,
system redundancy, and smaller gears which can reduce costs.
Smaller gearboxes and gears is just one way that moment of inertia
in the drive trains can be reduced which enables lower energy
losses. Rotation of generators directly and without gearboxes is
another way to reduce inherent energy losses and improve
efficiency. With the advent of slow rpm generators, annular
generators (18), and direct drive generators we can now eliminate
gearboxes in wave energy devices. Previous wave energy devices have
not been able to successfully prove the operation of, and thus
patent, a truly viable wave energy device without gearboxes. This
is now possible when annular or direct drive generators are used.
An electronic means by which to control electrical load (19) can be
installed to reduce if not eliminate the mass moment of inertia of
machinery items between wave up and down strokes. Switches (20) or
other means by which to ensure that all current goes to grid in the
desired direction or fashion can also be added so that one-way
clutches are not necessary. In essence, these switches or other
means make the reversing of up/down wave direction irrelevant. A
means by which to control electrical load, or any other means by
which to control the flexibility of the device about hinge points,
further enables the device to stay in sync with wave motions which
can improve if not optimize power output.
[0027] Patent applications must sufficiently describe a system for
the patent to valid. Furthermore, inventions are novel, beneficial,
and patentable when they greatly simplify existing inventions and
improve efficiency. Adding an item to an existing invention could
be considered infringement. Patent laws state that subtracting
items, however, can result in new patents. In summary, inventions
that result in fewer components, simplified systems, and higher
efficiencies are patentable. This is the case in this
invention.
* * * * *