U.S. patent application number 11/349524 was filed with the patent office on 2007-08-09 for drive-line mounted direct coupled ac generator for marine water craft.
Invention is credited to Gino Kennedy.
Application Number | 20070184728 11/349524 |
Document ID | / |
Family ID | 38334638 |
Filed Date | 2007-08-09 |
United States Patent
Application |
20070184728 |
Kind Code |
A1 |
Kennedy; Gino |
August 9, 2007 |
Drive-line mounted direct coupled AC generator for marine water
craft
Abstract
A direct coupled, drive-line power generating system for use
with marine water craft. The generator is preferably located
between the engine and the marine drive system providing an
auxiliary or primary source of substantially stabilized constant
voltage constant frequency AC power from a variable speed marine
engine.
Inventors: |
Kennedy; Gino; (North Fort
Myers, FL) |
Correspondence
Address: |
MCHALE & SLAVIN, P.A.
2855 PGA BLVD
PALM BEACH GARDENS
FL
33410
US
|
Family ID: |
38334638 |
Appl. No.: |
11/349524 |
Filed: |
February 7, 2006 |
Current U.S.
Class: |
440/3 |
Current CPC
Class: |
B63J 2003/002 20130101;
B63J 3/02 20130101 |
Class at
Publication: |
440/003 |
International
Class: |
B63H 21/20 20060101
B63H021/20 |
Claims
1. A direct coupled electrical generator for drive-line
installation on a marine water craft comprising: a variable speed
internal combustion engine providing rotational output; a generator
having a first and second side surface, said first side surface
coupled to said engine wherein said rotational output of said
engine produces an electrical output; means for correcting said
electrical output to a substantially stabilized constant AC voltage
having a constant frequency; a marine drive system connected to
said second side surface of said generator wherein said rotational
output of said engine supplies rotary motion to said marine drive
system during operation thereof; a propeller shaft having a
proximal end coupled to said marine drive system and a distal end
coupled to at least one propeller; whereby said variable speed
internal combustion engine drives said propeller through said
marine drive system and said generator, said generator generating
an electrical output of variable voltage variable frequency and
said means for correcting placing said electrical output into a
substantially constant AC voltage constant frequency.
2. The electrical generator of claim 1 wherein said generator is
sealed.
3. The electrical generator of claim 2 wherein said generator is
water cooled.
4. The electrical generator of claim 1 wherein said means for
correcting is further defined as an externally positioned
controller for converting said variable voltage variable frequency
electrical power to substantially stabilized constant AC voltage
having a substantially constant frequency.
5. The electrical generator of claim 4 wherein said controller is
water cooled.
6. The electrical generator of claim 4 wherein said means for
correcting adjusts AC voltage to a substantially stabilized
constant AC voltage constant frequency power for use onboard said
water craft.
7. The electrical generator of claim 4 wherein said means for
correcting is an AC to AC converter that adjusts AC voltage to a
substantially stabilized constant AC voltage constant frequency
power for use onboard said water craft.
8. The electrical generator of claim 4 wherein said means for
correcting includes a rectifier and an inverter, wherein said
rectifier converts said variable voltage variable frequency
electrical power to DC, wherein said inverter converts said direct
current into substantially stabilized constant AC voltage constant
frequency power for use onboard said water craft.
9. The electrical generator of claim 1 wherein said generator
includes a stator and a rotor.
10. The electrical generator of claim 1 wherein said generator
operates as a flywheel.
11. A direct coupled electrical generator for drive-line
installation on a marine water craft comprising: a variable speed
internal combustion engine having rotational output; a generator
connected to the rotatable output of said internal combustion
engine; an out-drive connected to said generator such that said
variable speed internal combustion engine supplies rotary motion to
said generator and said out-drive during operation thereof; a
propulsion means coupled to said out-drive; whereby said variable
speed internal combustion engine drives said generator at a
variable speed which in turn generates electrical power of variable
voltage and variable frequency.
12. The electrical generator of claim 11 including a controller for
converting said variable voltage variable frequency electrical
power to substantially stabilized constant voltage constant
frequency power.
13. The electrical generator of claim 12 wherein said means for
correcting adjusts AC voltage to a substantially stabilized
constant AC voltage constant frequency power for use onboard said
water craft.
14. The electrical generator of claim 12 wherein said controller
includes a rectifier and an inverter, wherein said rectifier
converts said variable voltage variable frequency electrical power
to direct current, wherein said inverter converts said direct
current into substantially stabilized constant voltage constant
frequency power for use onboard said water craft.
15. The electrical generator of claim 11 wherein said out-drive is
coupled to a propulsion system selected from the group consisting
of inboard drive, inboard-outboard drive, jet drive, and surface
drive.
16. The electrical generator of claim 11 wherein said generator is
sealed.
17. The electrical generator of claim 11 wherein said generator
includes a stator and a rotor.
18. The electrical generator of claim 11 wherein said generator
operates as a flywheel.
19. The electrical generator of claim 12 wherein said generator is
water cooled.
20. The electrical generator of claim 11 wherein said controller is
water cooled.
21. In a drive train of a water craft including at least one
variable speed internal combustion engine in mechanical
communication with at least one power transmission device which is
further in mechanical communication with at least one impeller
means constructed and arranged to provide motive thrust, the
improvement comprising: at least one generator for generating
electricity, wherein said generator is constructed and arranged for
direct coupling between said internal combustion engine and said
power transmission device; means for conditioning electrical power
produced by said generator to a substantially stabilized constant
voltage constant frequency electrical power.
22. The electrical generator of claim 21 wherein said generator is
sealed.
23. The electrical generator of claim 21 wherein said generator is
water cooled.
24. The electrical generator of claim 21 including a controller for
converting said variable voltage variable frequency electrical
power to substantially stabilized constant AC voltage having a
substantially constant frequency.
25. The electrical generator of claim 21 wherein said controller is
water cooled.
26. The electrical generator of claim 21 wherein said means for
correcting includes a rectifier and an inverter, wherein said
rectifier converts said variable voltage variable frequency
electrical power to DC, wherein said inverter converts said direct
current into substantially stabilized constant AC voltage constant
frequency power for use onboard said water craft.
Description
FIELD OF THE INVENTION
[0001] The field of the invention is marine generators and, more
specifically, a drive-line power AC generating system that is
directly coupled and delivers substantially stabilized constant
voltage constant frequency from a variable speed marine engine.
BACKGROUND OF THE INVENTION
[0002] In marine applications, the operation of water craft onboard
electrical AC appliances and electrical conveniences (e.g., air
conditioners, cooking ranges, microwaves, electric fans,
televisions, video cassette recorders, refrigerators, freezers,
coffee pots, blenders, hot water heaters, flood lighting,
battery-chargers, computers, etc.) required alternating current
("VAC"). While a water craft is moored, AC electric power can be
supplied by a removable shore power cable connection.
[0003] When a water craft is underway, or anchored apart from shore
power, use of VAC electric power is possible only be generation of
such power onboard the water craft. Typically, such power is from
the use of a generator set. Unfortunately, the space limitations
onboard a water craft is most limited. In fact, the marine industry
has long recognized that " . . . finding room for a genset can be a
problem, especially in boats in the less-than-40-foot range." Motor
Boating & Sailing/December 1999.
[0004] Unlike generator systems that are used on land, marine
generator systems must address inherent hazards, such as disposing
of hot exhaust gases, carbon monoxide issues, exposure to salt
water, all of which is compounded due to the lack of space
available. For optimum efficency, the internal combustion engine
must typically operate at continuously high RPMs to maintain the
proper voltage frequency. Thus, their operation produces an
inordinate amount of noise and vibration requiring larger mufflers,
sound enclosures, vibration isolators, and so on. Further, marine
electrical generating systems mounted inside the boat's hull
necessitates special installation requirements to permit safe
operation because of the hazards in operating internal combustion
engines in such an enclosed space.
[0005] Marine generator sets are heavy and, therefore, increase the
weight of the boat. In many cases, the designer must accommodate
for the weight of larger generators, as even a few hundred pounds
can cause a problem if improperly positioned within a boat hull.
Adding a generator set to the rear of a small marine water craft,
such as a 35 foot boat, can result in handling problems if the
weight is not balanced properly. A large portion of the weight
associated with marine generator sets can be attributed to the
internal combustion engines used in the generator sets, as well as
the elaborate muffler, sound enclosures and cooling systems
necessary for muffling the sound and cooling the internal
combustion engine. In addition, the cooling and muffler systems
occupy a large space, thereby diminishing the below-deck space.
Thus, this type of inboard power generating system is complex,
heavy, expensive to install, subject to many safety hazards while
operating, and is typically limited only to larger boats which have
ample space below deck for such an installation.
[0006] Another alternative for providing onboard electrical power
is via the use of inverters that convert DC battery power into AC
electrical power. However, several disadvantages exist in using
inverters. For example, the inverters are only good as long as
there is battery power; once the boat's battery(ies) are depleted,
the inverters are rendered useless, along with all other electrical
components requiring the battery power. In order to recharge the
batteries with the small alternator provided on most marine
engines, the engine must be run for an extended period of time. In
addition, when inverters are used to supply power to appliances,
additional batteries are required to allow sufficient amperage draw
extended use without depleting the batteries. The additional
batteries are expensive, heavy, and if wet cell type, hard to
maintain. A single 8D battery can weight 150 lbs, quickly
increasing the weight of the boat.
[0007] While auxiliary generators are the primary means for
providing electrical power to water craft that is anchored or under
way, the following U.S. patents provide examples of other attempts
to address the problems with marine generator systems. U.S. Pat.
No. 3,619,632 to Labombarde discloses an outboard Direct Current
generator unit for sailboats. The outboard generator unit comprises
a housing arranged to be attached to the transom of a sailboat. A
propeller is mounted in a housing coupled via a drive shaft to the
generator so that when the sailboat is moving through the water,
the propeller is rotated, thereby rotating the generator and
producing Direct Current electricity. The DC is then fed via cables
back to a bank of batteries stored in the hold of the boat that is
shared by the inboard propulsion engine.
[0008] U.S. Pat. No. 4,010,377 to McKenzie discloses a generator
mounted on a propulsion unit of an outboard motor through an
interposed adaptor. The adaptor includes various plug receptacles
into which electrical plugs can be connected to provide electrical
power to electrical appliances in the boat on which the unit is
mounted. This generator fails to disclose a method of controlling
the voltage and frequency, which are dependent upon engine speed in
such an installation.
[0009] U.S. Pat. No. 6,435,925 discloses an outboard marine
generator having the appearance of an outboard motor. The generator
and engine is placed into a housing that appears similar to an
outboard motor except there is no propellor or drive system. The
device is designed to secure to the transom of a boat in a similar
manner as an outboard engine.
[0010] U.S. Pat. No. 6,624,533 is a power controller employing DC
bus voltage. In the preferred embodiment the DC-DC converter is
adapted to transfer electrical power from a battery to supplement
DC bus voltage during high loads. When the generator is off, an
inverter provides AC power and in one embodiment automatically
starts the engine. Still another embodiment includes a voltage
sensor adapted to control engine speed as a function of the DC
voltage bus.
[0011] U.S. Pat. No. 5,011,442 to Polcz et al. discloses an
auxiliary power generating means for outboard motors including an
alternator adapted for installation between the flywheel and the
recoil starter of an outboard engine. The auxiliary power
generation device includes output electrical connections for
providing electrical power to electrical appliances on the boat.
However, such a device could only be used for small installations
due to the side loading of such devices. The side loading required
large brackets and belts, all of which is limited in practice to
the production of a small KW output.
[0012] U.S. Pat. No. 3,812,379 to Kaufman et al. discloses a
combination propulsion system for boats. The propulsion system is
an outboard mounted unit including an engine and an electric motor
and means for coupling the motor to the engine, whereby the
electric motor can be reversed for use as a generator when the
engine is running. In this mode of operation, the battery for the
motor can be recharged.
[0013] Thus, there remains a need for an electrical generating
system capable of providing an economical, safe, reliable, and
quiet means of generating electricity for large and small boats.
The system should provide AC electrical power of substantially
stabilized constant voltage constant frequency during operation of
at least one of the propulsion engines. The system should be
adapted to cooperate with new as well as pre-existing boat
drive-lines with minimum modification.
SUMMARY OF THE INVENTION
[0014] The instant invention provides a new and improved AC power
generating system for marine water crafts. More specifically, the
instant invention provides a AC power generating system that fits
between the engine and marine drive system within the drive-line of
the boat's propulsion system. The power generating system delivers
substantially stabilized constant voltage constant frequency
throughout the operational range of a marine engine.
[0015] A marine propulsion system normally comprises a Prime Mover,
such as a diesel or gasoline internal combustion engine, coupled to
a marine drive system or an out-drive. Out-drives are typically
available in the form of an inboard-outboard drive, jet drive,
surface drive, or the like. The output of the marine drive system
or out-drive is operably connected to a propeller for rotation in
response to operation of the engine. In such systems the engine
speed varies over the operational envelope of the water craft. The
instant invention positions a generator between the prime mover and
the marine drive system or out-drive to deliver substantially
stabilized constant voltage constant frequency power for use in
powering AC devices on board the marine water craft.
[0016] In one embodiment, the generator includes a generator
housing suitable for securement to the rear portion, e.g. bell
housing flange, of the engine block as well as the mounting flange,
e.g. bell housing, of the marine drive system or out-drive
assembly. A stator and rotor are removably mounted within the
generator housing around the inside perimeter thereof, and a rotor
is mounted for rotation within the stator in response to rotation
of the engine. A first end of the rotor is constructed and arranged
for cooperation with the crankshaft of the engine, and a second end
of the rotor is constructed and arranged for cooperation with the
input shaft of the marine drive system or out-drive. In this
manner, when the engine rotates, the rotation will be imparted to
the rotor of the generator as well as the input shaft of the marine
drive system or out-drive. A controller is in electrical
communication with the generator to accept the variable frequency
and variable voltage power produced thereby. The controller is
constructed and arranged to convert the variable frequency variable
voltage into substantially stabilized constant AC voltage, constant
60 Hz (or 50 Hz for Europe) frequency power for use on the water
craft.
[0017] A second embodiment of the instant invention replaces the
Original Equipment Manufacturer (OEM) engine flywheel with a rotor
flywheel having permanent magnets inset either on the flywheel or
surrounding the flywheel. In this embodiment the stator is mounted
within the bell housing flange of the engine and the marine drive
system or out-drive bell housing is mounted to the bell-housing
flange. The variable output from the generator is supplied to the
controller, as in the previously described embodiment, which
produces substantially stabilized constant voltage constant
frequency.
[0018] Accordingly, it is a general objective of the instant
invention to provide a drive line mounted, direct drive apparatus
which improves upon and overcomes the disadvantages of the prior
art.
[0019] It is another objective of this invention to provide a
solution to a long felt need of safely generating AC electrical
power for utilization onboard a water craft (e.g., power boats,
sailboats, inboard/outboard engines, inboard engines and the
like).
[0020] It is another object of this invention to provide an
apparatus for supplying AC electrical power to equipment onboard a
water craft (e.g., power boats, sailboats, inboard/outboard
engines, inboard engines, and the like) wherein the apparatus is
specially designed for boats with little or no space.
[0021] It is another object of this invention to provide an
apparatus for supplying AC electrical power to equipment on board a
water craft (e.g., power boats, sailboats, inboard/outboard
engines, inboard engines, and the like) wherein the device is
mounted in-line with the marine vessel's drive-line.
[0022] It is another object of this invention to provide an
apparatus for supplying AC electrical power to equipment on board a
water craft (e.g., power boats, sailboats, inboard/outboard
engines, inboard engines, and the like) wherein the device is
mounted between the rear portion of the engine and the front
portion of the marine drive system within the vessel's
drive-line.
[0023] It is still another object of this invention to provide an
apparatus for supplying AC electrical power to on board equipment
on a water craft (e.g., power boats, sailboats, inboard/outboard
engines, inboard engines, and the like) wherein the power generated
is independent of the water craft's motion.
[0024] It is still another object of this invention to provide an
apparatus for supplying AC electrical power to equipment on board a
water craft (e.g., power boats, sailboats, inboard/outboard
engines, inboard engines, and the like) which is simple to install,
and which is ideally suited for original equipment and aftermarket
installations.
[0025] It is still yet a further object of this invention to
provide an apparatus for supplying AC electrical power to equipment
on board a water craft (e.g., power boats, sailboats,
inboard/outboard engines, inboard engines, and the like) that
minimizes noise and vibration during operation of the
apparatus.
[0026] It is still yet another object of this invention to provide
an apparatus for supplying AC electrical power to on board
equipment on a water craft (e.g., power boats, sailboats,
inboard/outboard engines, inboard engines, and the like) that can
be inexpensively manufactured and which is simple and reliable in
operation.
[0027] It is still yet another object of this invention to provide
an apparatus for supplying AC electrical power to equipment on
board a water craft (e.g., power boats, sailboats, inboard/outboard
engines, inboard engines, and the like) that minimizes fume and
combustion hazards by utilizing the prime mover of the vessel's
propulsion. system for electrical power generation.
[0028] It is still yet another object of this invention to provide
an apparatus for supplying AC electrical power to equipment onboard
a water craft (e.g., power boats, sailboats, inboard/outboard
engines, inboard engines, and the like) that is light weight in
comparison to conventional generator sets used onboard boats.
[0029] It is even yet a further object of this invention to provide
an apparatus for supplying AC electrical power to onboard equipment
on a water craft (e.g., power boats, sailboats, inboard/outboard
engines, inboard engines, or sails, etc.) that may utilize
water-cooling of the generator and/or controller for maximum
electrical power generation.
[0030] It is even yet a further object of this invention to provide
an apparatus for supplying AC electrical power to onboard equipment
on a water craft (e.g., power boats, sailboats, inboard/outboard
engines, inboard engines, or sails, etc.) that provides electrical
power when a marine water craft is operating at a slow speed
without the need of a separate generator set.
[0031] Other objectives and advantages of this invention will
become apparent from the following description taken in conjunction
with any accompanying drawings wherein are set forth, by way of
illustration and example, certain embodiments of this invention.
Any drawings contained herein constitute a part of this
specification and include exemplary embodiments of the present
invention and illustrate various objects and features thereof.
BRIEF DESCRIPTION OF THE FIGURES
[0032] FIG. 1 is a schematic view of one embodiment of the instant
invention;
[0033] FIG. 2 is a side view illustrating one embodiment of the
instant invention;
[0034] FIG. 3 is a side view illustrating one embodiment of the
instant invention.
DETAILED DESCRIPTION OF THE INVENTION
[0035] Although the invention is described in terms of a preferred
specific embodiment, it will be readily apparent to those skilled
in this art that various modifications, rearrangements and
substitutions can be made without departing from the spirit of the
invention. The scope of the invention is defined by the claims
appended hereto.
[0036] Referring to FIG. 1 and 2, a preferred, albeit non-limiting
embodiment is illustrated. Set forth is a propulsion system for a
marine water craft at 10. The propulsion system comprises a
conventional variable speed internal combustion engine 12, a marine
drive system 14 which is commonly referred to as a transmission, a
reversible driven propeller shaft 16 and a fixed pitch propeller
18. Positioned and operably coupled between the engine and the
marine drive system, such as a transmission or out-drive, is a
generator 20. In one embodiment, the generator includes a generator
housing 22 suitable for securement to the rear portion, e.g. bell
housing flange 24, of the engine block 26 as well as the mounting
flange, e.g. bell housing 28, of the marine drive system assembly.
A stator (not shown) is removably mounted within the generator
housing 22 around the inside perimeter thereof and a rotor (not
shown) is mounted for rotation within the stator in response to
rotation of the engine. A first end 30 of the rotor is constructed
and arranged for cooperation with the crankshaft (not shown) of the
engine 12 and a second end 32 of the rotor is constructed and
arranged for cooperation with the input shaft of the marine drive
system. In this manner, when the engine rotates the rotation will
be imparted to the rotor of the generator as well as the input
shaft 35 of the marine drive system 14. It should be noted that the
generator can also be sized and weighted to operate as a flywheel
thereby replacing the conventional flywheel. A controller 34 is in
electrical communication with the generator to accept the variable
frequency and variable voltage power produced thereby. The
controller includes a rectifier 36 for converting the three phase
variable frequency and variable voltage produced by the generator
and converting it to direct current (DC) power. The DC power is
supplied to an invertor 38 which converts the DC power to single or
three phase AC constant voltage constant frequency power for use on
the water craft. The generator housing may be sealed and further
include a water inlet 37 in communication with a water cooling
jacket (not shown) constructed and arranged to cool the stator and
a water outlet 39. The water inlet and outlet may be connected to
the engine cooling system or alternatively may be connected to an
independent cooling system suitable to provide a sufficient amount
of water to control the operating temperature of the generator.
Alternatively, a frequency converter or an AC to AC converter can
be employed.
[0037] It should be noted that in the system described above, other
types of marine drive systems may be termed a transmission without
departing from the scope of the invention Such drive systems may
include, but should not be limited to out-drives in the form of
inboard-outboard drives, jet drives, surface drives, V-drives and
the like.
[0038] Referring to FIG. 3 an alternative embodiment is
illustrated. In this embodiment the OEM flywheel is removed from
the engine 12 and replaced with a rotor flywheel 40 having
permanent magnets 42 inset therein. The rotor flywheel also
includes a starter ring 44 for cooperation with a starter 46. A
stator (not shown) is removably mounted within the bell housing
flange 24 of the engine 12 to surround the perimeter of the rotor
flywheel 40. A controller 34 is in electrical communication with
the generator to accept the variable frequency and variable voltage
power produced thereby. The controller includes a rectifier 36 for
converting the variable frequency and variable voltage power from
the generator and converting it to direct current DC power. The DC
power is supplied to an invertor 38 which converts the DC power to
single phase AC constant voltage constant frequency power for use
on the water craft.
[0039] Alternatively, the controller adjusts variable AC voltage
and frequency from a variable speed motor to a substantially
stabilized constant AC voltage constant frequency power.
[0040] One of the major advantages of the instant invention is the
space saved below deck of the water craft. The only additional
space below deck that is required is the length of the generator.
Since it is positioned between the engine and the marine drive
system, this space could easily be obtained by shortening the
propeller shaft. Another advantage occurs when the marine water
craft is operated at slow speeds, such as in "No Wake" zones or
areas. Normally appliances that require high amounts of power, such
as refrigerators and air conditioners, are operated during these
periods. Rather than utilizing an auxiliary generator set and
encountering the problems of operating another engine, the main
propulsion engine is used to operate the generator. A further
advantage is that the weight of an auxiliary engine need not be
added to the water craft, therefore the existing balanced
distribution of weight may be maintained.
[0041] This invention is especially beneficial on sailboats. Most
sailboats have a small engine to propel the boat when not under
sail; for example, when the sailboat is in a harbor or in close
proximity to a dock. Also, the limited below deck space on
sailboats is extremely valuable. Providing a generator set on a
sailboat consumes valuable space and may require an additional
supply of fuel. The instant invention overcomes these problems by
locating the generator between the propulsion engine and the marine
drive system. The only additional space required would be that
equal to the length of the generator. This again could be obtained
by shortening the propeller shaft. Also, the additional weight of
an auxiliary engine is not added to the sailboat which may upset
the proper distribution of weight.
[0042] It is to be understood that while a certain form of the
invention is illustrated, it is not to be limited to the specific
form or arrangement herein described and shown. It will be apparent
to those skilled in the art that various changes may be made
without departing from the scope of the invention and the invention
is not to be considered limited to what is shown and described in
the specification and any drawings/figures included herein.
[0043] One skilled in the art will readily appreciate that the
present invention is well adapted to carry out the objectives and
obtain the ends and advantages mentioned, as well as those inherent
therein. The embodiments, methods, procedures and techniques
described herein are presently representative of the preferred
embodiments, are intended to be exemplary and are not intended as
limitations on the scope. Changes therein and other uses will occur
to those skilled in the art which are encompassed within the spirit
of the invention and are defined by the scope of the appended
claims. Although the invention has been described in connection
with specific preferred embodiments, it should be understood that
the invention as claimed should not be unduly limited to such
specific embodiments. Indeed, various modifications of the
described modes for carrying out the invention which are obvious to
those skilled in the art are intended to be within the scope of the
following claims.
* * * * *