Note: Descriptions are shown in the official language in which they were submitted.
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LIQUEFIED FUEL GAS POWERED RECREATIONAL VEHICLE
RELATED APPLICATIONS
[0001]
FIELD OF THE INVENTION
[00021 The present invention relates generally to motorized recreational
vehicles
and more particularly to snowmobiles, personal watercraft, all terrain
vehicles, motorcycles and
the like.
BACKGROUND OF THE INVENTION
[00031 Conventional snowmobiles have used two-cycle engines. Two-cycle
engines are characterized by a relatively simple engine configuration having
the advantages of
being lightweight and compact and still providing high power. When used to
power a
snowmobile, other desirable characteristics of two-cycle engines include the
relative simplicity
of the engine and relatively high power-to-weight and power-to-size ratios of
these engines.
[0004] Current trends and regulations demand a quiet, clean and environment-
friendly engine for use with recreational motor vehicles. In some settings,
four-cycle engines
have been utilized as alternative power sources. In general, two-stroke
engines inherently have
higher exhaust emissions than comparably sized four-cycle engines due to: 1)
the necessity of
opening the exhaust ports subsequent to complete ignition of the fuel/air
mixture, 2) unburned
fuel escaping the exhaust port during the intake cycle of the cylinder, and 3)
lubrication oil
mixing with the intake air.
[0005] While four-cycle engines are now widely found on outdoor power
equipment and vehicles, for example, snowthrowers, lawnmovers, all terrain
vehicles,
motorcycles, etc., these engines have substantial limitations. For example,
four-cycle engines
are less desirable for powering snowmobiles due to the low power-to-
weight/size ratios, as four-
cycle engines are heavier than comparable two-cycle engines. Snowmobile
handing and
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performance characteristics are sensitive to weight increases. Additionally,
the relatively
compact chassis and body of a snowmobile limits the space available for the
engine.
[0006] The rapidly rising cost of gasoline and stricter emission controls have
encouraged interest in the use of alternative fuels in engines instead of
gasoline. One of the
alternatives is a class of fuels referred to as gaseous fuels. Examples of
these fuels are liquefied
petroleum gases (LPG) containing propane or butane or mixtures of both, and
liquefied natural
gas (LNG). It is understood that reference herein to propane or LPG is meant
to include any or
all of the gaseous fuels.
[0007] The foregoing has outlined rather broadly the features and technical
advantages of the present invention in order that the detailed description of
the invention that
follows may be better understood. Additional features and advantages of the
invention will be
described hereinafter which form the subject of the claims of the invention.
It should be
appreciated by those skilled in the art that the conception and specific
embodiment disclosed
may be readily utilized as a basis for modifying or designing other structures
for carrying out the
same purposes of the present invention. It should also be realized by those
skilled in the art that
such equivalent constructions do not depart from the spirit and scope of the
invention as set forth
in the appended claims. The novel features which are believed to be
characteristic of the
invention, both as to its organization and method of operation, together with
further objects and
advantages will be better understood from the following description when
considered in
connection with the accompanying FIGURES. It is to be expressly understood,
however, that
each of the FIGURES is provided for the purpose of illustration and
description only and is not
intended as a definition of the limits of the present invention.
SUMMARY OF THE INVENTION
[0008] The invention relates to a recreational motor vehicle, such as a
snowmobile,
personal watercraft, all terrain vehicle (ATV) and the like, with an internal
combustion engine
which is fueled with a liquefied fuel gas, such as, for example, liquefied
propane (LP).
[0009] In one embodiment, internal combustion engine is provided with
pressurized intake air from, for example, a supercharger or turbocharger. In
other embodiments,
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the engine uses atmospheric air. A snowmobile may include an air charging
system and an
intercooler system.
[0010] In one embodiment, the present invention contemplates a snowmobile
having a chassis that includes a track tunnel portion; a track located within
the tunnel portion;
and an engine mounted to the chassis, and including an air intake assembly and
an exhaust
assembly.
[0011] An especially desirable characteristic of propane-powered engines is
the
substantial reduction in emissions. The present invention minimizes many of
the problems
associated with two-cycle and conventional four cycle engines and makes it
possible to use
gaseous fuels effectively, economically, and efficiently in internal
combustion engines of
recreational motor vehicles.
[0012] In one embodiment, the present invention contemplates a snowmobile
having a pressurized fuel tank located between the operator seat and the track
tunnel portion.
Such a tank may include a plurality of cylindrical tanks. In another
embodiment, the present
invention contemplates a personal watercraft having a pressurized fuel tank
located underneath
the operator seat or in the bow or front portion of the watercraft.
[0013] Embodiments of the present invention provide a recreational motor
vehicle
which utilizes a gaseous fuel IC engine as an alternative to conventional
gasoline-powered two-
cycle and four cycle engines, while producing sufficient engine output, and
remaining relatively
small and light weight.
[0014] Another advantage of an embodiment of the present invention is that the
charged air engine in the recreational motor vehicle need not require a
premium grade of
gasoline to operate properly.
[0015] An added advantage of an embodiment of the present invention is that
the
engine cold starting capability is improved since the fuel will enters the
engine as a pre-mixed
gaseous vapor.
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[0016] Another advantage of an embodiment of the present invention is that
there
is minimal turbo lag in the system since the total air volume in the engine
system is kept to a
minimum.
[0017] A further advantage of an embodiment of the present invention is that
the
intercooler system for the air charger is effective even during operation of
the snowmobile under
high engine load, low forward speed conditions, such as when climbing a hill.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIGURE 1 is an elevational view of a depiction of a snowmobile
embodying the principles of the present invention.
[0019] FIGURE 2 is a schematic view of the air intake system of the present
invention.
[0020] FIGURE 3 is a perspective view of a component of an air intake of
FIGURE 2.
[0021] FIGURE 4 is a perspective view of a component of an air intake system
of
FIGURE 2.
100221 FIGURE 5 is a schematic view of a component of an air intake system of
FIGURE 2.
[0023] FIGURE 6 is a bottom elevational view of a component of an air intake
system of FIGURE 2.
[0024] FIGURE 7 is a cross-sectional depiction of the component of FIGURE 6
taken through a centerline.
[0025] FIGURE 8 is a top elevational view of a component of an air intake
system
of FIGURE 2.
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[0026] FIGURE 9 is a schematic illustration of another embodiment of an air
intake system according to the present invention.
[0027] FIGURES 10 - 13 are perspective views of a snowmobile incorporating
aspects of the present invention.
[0028] FIGURES 14 - 16 are various schematic views of alternative embodiments
of an air intake system in accordance with the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0029] FIGURE 1 shows a snowmobile 10 embodying the principles of the present
invention. Snowmobile 10 has a frame 11 and an endless driven track system 12
mounted to a
rearward portion of frame 11. Snowmobile 10 utilizes an internal combustion
engine indicated
at 13 to provide power generation. Engine 13 is operatively connected to the
belt drive system
12 to provide movement to snowmobile 10. Snowmobile 10 includes a seat 14
whereon a driver
may be positioned in a seated manner. The driver straddles seat 14 during use
and foot rests are
provided by side steps 19. A steering assembly 15 is located forward of seat
14 and is
operatively coupled to a pair of skis 16 providing steering capability to
snowmobile 10. Engine
13 will include some type of engine cooling system, which may employ, for
example, air cooling
or liquid cooling, but this system does not form part of the present
invention, and can be
conventional in nature, so it will not be discussed further herein. While the
illustrated preferred
embodiment of the present invention is a snowmobile, it is envisioned that the
present invention
could also be embodied within a variety of different recreational motor
vehicles, such as, but not
limited to, personal water craft and all terrain vehicles (ATV).
[0030] As described in more detail herein, snowmobile 10 includes a propane
fueled engine providing heretofore unattainable performance characteristics
while providing a
substantial reduction in emissions. Given the air and noise pollution
generated by two-cycle
engines, current regulations restrict access to certain federal areas and/or
National Parks to four
cycle snowmobiles. It is envisioned that embodiments of snowmobiles of the
present invention
would provide an even greater reduction in emissions as compared to four-cycle
snowmobile
engines. Future snowmobile access in such protected areas may be further
restricted to
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embodiments of the present invention, especially given the substantial
reduction of air and noise
emissions.
[0031] Track system 12 includes a drive track 17, a drive wheel (not shown)
arranged near engine 13, idler wheels 18 arranged near the rear end of frame
11. Track system
12 also includes a suspension mechanism 20. A frame tunnel is positioned
between components
of track system 12 and suspension system 20 and seat 14.
[0032] One embodiment of an engine system of the present invention is shown
schematically in FIGURE 2. As shown in FIGURE 2, air from the atmosphere
enters an air filter
30, flows through conduit 31 and enters turbocharger 32. Turbocharger 32
compresses the intake
air. Intake air temperature increases due to heat generation during the
compression process.
While this embodiment includes turbocharger 32, alternative embodiments of the
present
invention may be naturally aspirated, such as depicted in FIGURE 9.
[0033] Referring again to FIGURE 2, temperature and pressure of the air
exiting
turbocharger 32 are greater than a pressure and temperature of the air
entering the turbocharger
32. The heated and pressurized air then flows through charge tube 34 toward
mixer 43. Bypass
valve (waste gate) 36 is a pressure relief valve. The compressed air passes
into intercooler 35
prior to being combined with fuel at mixer 43. Intercooler 35 is arranged to
remove heat from
the pressurized intake air such that at an exit point, the temperature of the
air is less than the
temperature of the air at the entrance point. Fuel, such as propane, is
provided by tank 40 and
passes through valve 41 prior to introduction into heat exchanger/converter
42. Plenum 45
receives the cooled, compressed intake air/fuel mixture from converter 42 and
passes it into
throttle bodies 70 of engine 13. Exhaust gases exit engine 13 and are directed
to turbocharger 32
and exit snowmobile 10 through an exhaust system, which may include a muffler
(not shown).
[0034] Heat exchanger/converter 42 warms the liquefied fuel gas from its cold
state
to a temperature that permits more efficient operation of internal combustion
engine 13. It
another embodiment, it may be possible to combine all or portions of heat
exchanger/converter
42 with intercooler 35 to provide a heat exchange system which is more
compact. In a preferred
example, heat exchanger/converter 42 is a LPG vaporizer with built-in
regulation, such as
manufactured by IMPCO, Technologies of Santa Ana, California. The IMPCO
converter is a
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combined two-stage regulator and vaporizer. In general, it receives liquid
fuel at tank pressure
from the filter/fuel lock and reduces pressure in two stages to slightly less
than atmospheric.
When the engine is cranking or running, a partial vacuum is created in the
vapor line to the
carburetor, which opens the regulator permitting fuel to flow to the
carburetor. In the process of
reducing the pressure in the tank to atmospheric, the liquid propane expands
to become a vapor,
absorbing heat in the process. Water from the engine cooling system circulates
through a heat
exchanger to avoid internal freeze up. A regulator seals off fuel flow when
the engine is
stopped.
[0035] As shown in FIGURE 2, turbocharger 32 communicates with the outlet of
air filter 30 via conduit 31. Conduit 31 is preferably a rigid metallic
tubular member with a
configuration that allows a relatively direct path from air filter 30 to
turbocharger 32. It is
contemplated that the configuration of conduit 31 may include one or more
bends to
accommodate positioning of various engine or snowmobile components and the
relative
positions of air filter 30 and turbocharger 32. It is also contemplated that
conduit 31 may have a
flexible metallic configuration or may be formed of plastic material. However,
due to the heat
present at the relative proximity of engine 13, it is preferable for the
conduit 31 to be relatively
resistant to high-heat environments.
[0036] Turbocharger 32 includes a compressor portion 50 and a turbine portion
51.
Compressor portion 50 has an inlet which is connected to conduit 31, as
described above, and
has an outlet that is connected to conduit 34. Turbine portion 51 includes an
inlet and an outlet.
Turbocharger 32 utilizes energy provided by engine 13 exhaust to compress
(pressurize) air from
the atmosphere. For the turbocharger shown in the FIGURES, a rotor of turbine
structure 51 is
connected to a common rotor of compressor structure 50 so as to rotate in
unison therewith. It is
noted that any other type of turbocharger may be used, including types that
have separate
turbines and compressors that are linked, for example by a rigid shaft that
extends therebetween.
[0037] Bypass valve 36 and blowoff valve 72 control air pressure within the
intake
system during operation. A pressure setting of valves 36, 72 may be
adjustable, for example, to
vary performance needs of engine 13. In some embodiments, valves 36, 72 may be
controlled by
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an engine control unit 60, based upon inputs from a charge air temperature
and/or pressure
sensor, a knock sensor, in addition to other conventional inputs to the engine
control unit.
[0038] bypass valve 36 is located as close to turbo 32 as possible. Valve 36
controls turbo surge and allows turbo to spool quickly. The exit hole in the
charge tube 34 for
valve 36 is between 7/8"ID and 1.250"ID. Blow off valve 72 is located between
intercooler 35
and mixer 43. This positioning allows excess pressure to be quickly released
during throttling
down so as to prevent over-pressurizing mixer 42 and plenum 45 and thus
minimizing the
occurrence of a flooded engine condition. The exit hole in charge tube 34 for
valve 72 is between
3/8"ID and l"ID.
100391 Tank 40 contains a liquefied fuel gas, such as liquefied propane (LP),
liquefied petroleum gas (LPG) or liquefied natural gas (LNG). LP is a
preferred fuel gas. A
regulator may be used to control gas pressure released from tank 40.
Alternatively, a
heater/converter unit can be utilized to control gas pressure released from
tank 40. The benefits
of the use of liquefied fuel gas with turbocharger 43 in conjunction with
engine 13 include
enhanced performance, improved efficiency and a substantial decrease in
emissions.
[0040] Heat exchanging intercooler 35 may be located proximate the forward
portion of snowmobile 10. It may be optimal for intercooler 35 to be mounted
in a different
position relative to the movement of air produced from forward movement of
snowmobile 10.
Intercooler 35 is constructed and arranged to dissipate heat from the
pressurized intake air prior
to introduction into mixer 43. It is preferable for intercooler 35 to be
formed of a heat
conductive material such as metal, for example, aluminum or steel and
conFIGUREd so as to
minimize air flow resistance and pressure loss of the air flowing therein. It
is also preferable to
keep the size of intercooler 35 to a minimum, to maintain a space efficient
design of engine 13.
[0041] It is preferable for plenum 45 to be connected to engine air intake in
a
relatively direct manner, so as to minimize the air travel distance between
plenum 45 and engine
13. Plenum 45 may be preferably formed of a metallic material. However, it is
contemplated
that a rigid polymer material may also be utilized. Plenum 45 is preferably a
substantially
hollow enclosure, which possesses a relatively small volume. It is noted that
the plenum volume
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may be altered with respect to engine size, engine operating characteristics,
and/or turbocharger
output.
[0042] While prior art propane systems place a mixer directly on the throttle
body
or carburetor via a mounting bracket or plate. A system in accordance with the
present invention
uses plenum 45 between mixer 43 and the throttle bodies (or carburetor bodies)
70. One
embodiment of plenum 45 is shown in FIGURE 3. In this embodiment, plenum 45
includes an
air/fuel inlet port 62 provided in fluid communication with four outlet ports
64 via interior
volume 66. Outlet ports 64 are coupled to throttle bodies 70. Ideally a volume
of plenum 45
should be of a specific size in relation to the size of the engine. In another
embodiment, plenum
45 could be incorporated as part of the intercooler as long as it is located
between the mixer and
throttle bodies. This plenum approach works on naturally aspirated motors as
well as in
conjunction with turbo charged or super charged motors.
[0043] It has been detennined that a preferred working ratio for the size of
the
plenum is needed for proper engine performance. On the smaller end of the
scale plenum 45
would have a total volumetric size of 11 % of the total volume of the engine.
On the larger side it
would have a volumetric size of 110.6% of the total size of the engine.
100441 Example: Using a 1000 cc motor as a model.
[0045] Smallest plenum would be 110 cc or 11 % of total cc's of motor.
[0046] Largest plenum would measure 11,066.02 cc or 110.6% times the total
motor cc's
[0047] A more preferred range for plenum 45 sizing would be between 340 - 700
cc for a 4-cylinder, 1000 cc motor. For a I000cc, 3-cylinder motor, a more
ideal range of
plenum 45 size would be between 255 and 525 cc.
[0048] Referring again to FIGURE 2, the engine system includes a means for
priming the engine during cold starts, etc. Existing propane systems include a
primer button on
top of a converter cap. This button is designed to give an extra shot of
propane directly into the
vapor supply line running from the converter to the mixer. Though this factory
system works
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moderately well it is inconvenient to get off the vehicle and reach down under
the hood or
having to take the hood off in order to reach the button at the same time
trying to start the motor.
Another limitation of the prior art system is that propane vapor is introduced
directly into the
mixer. Applicants have determined that other configurations of the priming
system are more
beneficial during startup.
[0049] To better facilitate cold starts, an engine system in accordance with
the
present invention incorporates primer line 80 which conveys vaporous gas from
converter 42
directly into the intake system between mixer 43 and plenum 45. Primer line 80
should either be
of a specific inside diameter or an orifice or jet or reducer should be
provide in line 80 to allow
the proper amount of gaseous vapor to enter the intake tract at the proper
time. Line 80 should
have a diameter between .020" to .099" I.D. As revealed in testing, a smaller
orifice doesn't
allow enough fuel to facilitate start up and a line larger than .099"I.D.
introduces too much fuel,
resulting in flooding.
[0050) As shown in FIGURES 2 and 4, electric solenoid valve 82 is used to
control the fuel to enter at the proper time and then remain shut during
operation of engine 13.
This may be accomplished by wiring the solenoid valve 82 directly in
conjunction with the
wiring start up relay system employed by the machine when starting the engine
13. When the
engine is being started, a starter motor is activated which turns engine 13
over at a sufficient
speed to allow start up. When the start key is released engine 13 will
continue to run and the
electric primer system will automatically turn off. An optional remote on/off
switch may be
installed to completely render the primer system inoperative if so desired.
For instance, once the
motor is warmed up the primer system might not be necessary to facilitate
start up.
[0051] Balance line 84 is to balance the air pressures between the converter
42
and charge tube 34. Without this air balance, converter 42 is often unable to
deliver sufficient
quantities of fuel to the engine. As shown in FIGURE 9, a naturally aspirated
engine does not
require this balance line, as converter 42 is already open to atmospheric
pressure. Existing
systems typically attach a balance line directly to a converter cap at a right
angle (perpendicular
to the converter diaphragm).
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[0052) In order to provide improved performance, balance line 84 should be
coupled to an interior of charge tube 34. FIGURE 5 illustrates various
different configurations
of an end 86a - 86d of balance line 84 as it protrudes into charge tube 34 at
an angle relative to
the direction of air flow. End 86 of balance line 84 is ideally flared. This
shape, location and
angle of end 86 cooperate to capture airflow very quickly from the spooling up
turbo. In
comparison, if end 86 is simply inserted into charge tube 34 at a right angle
relative to direction
of air flow, balance line 84 may see a vacuum until tube 34 reaches full
charge pressure. Even
with a high air flow from the turbo, there may be a tendency in the balance
line of the prior art to
draw a vacuum on line 84 instead of pressurizing it. By configuring and
positioning end 86 as
shown in FIGURE 5, improved engine performance is obtained.
[0053] Converter 42 relies on a signal pressure coming through balance line 84
in
order to properly deliver the right amount of fuel at the right time. For
proper performance,
balance line 84 should be between 3/16" and 5/8" ID. A line smaller or larger
than this delays
the pressure signal and thus delays the overall response time. The length of
balance line 84
should be as short as possible ranging from 1" to a maximum of 2.5 ft.
100541 Referring to FIGURES 6-8, applicant has discovered that coupling the
other
end of line 84 in a generally parallel manner relative to the cap 90 of
converter 42 yields
optimum results. By providing such a coupling between line 84 and converter
42, the pressure
signal is better distributed across the diaphragm within converter 42. In
comparison, the prior art
approach having a 90 degree angle (of air flow relative to diaphragm) delays
the pressure signal
as air flow is directed around an abrupt bend before interacting with the
diaphragm under the
converter cap 90. The horizontal or slightly angled approach as disclosed
herein tends to
distribute the pressure signal evenly across diaphragm resulting in better
throttle response. As
shown in FIGURES 6- 8, inlet port 92 is positioned on side of converter cap
90. A transition
region 94 promotes smooth air flow through port 92. In this embodiment,
airflow through line
84 at port 92 is generally parallel to the diaphragm. An improvement in the
responsiveness of
engine 13 can be yielded by such positioning of port 92 relative to the
diaphragm within
converter 42.
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[0055] FIGURE 9 illustrates a naturally aspirated system 500 in accordance
with
the present invention. System 500 draws air through air intake and fuel
through heater/converter
42 into mixer 43. An air/fuel mixture is drawn through plenum/intake manifold
45 into engine
13.
[0056] FIGURES 10 - 13 illustrate various component locations of another
embodiment of a snowmobile incorporating aspects of the present invention. As
shown in
FIGURE 9, cowl 62 directs air into intercooler 35. FIGURE 10 illustrates the
location of
turbocharger 32, positioned between engine 13 and operator seat 14. FIGURES 11
- 13 show
tank 40 conFIGUREd as a pair of generally cylindrical tanks 80, 81. Tanks 80,
81 are preferably
positioned between the track tunnel and seat 14. Tanks 80, 81 can be in fluid
communication
with each other or a valve(s) could be used to access each tank separately.
Fuel lines (not
shown) direct fuel to the heater/converter 42, which, in this example, is
within the engine
compartment. Seat 14 may be coupled directly to tanks 80, 81 or may be coupled
to frame 11.
Tanks 80, 81 are preferably aligned with a direction of forward motion. Tank
volume ranges
from 2 to 40 gallons. Access to tanks 80, 81 may be provided by removal of
seat 14.
Alternatively, access for filling tanks 80, 81 may be provided at a readily
accessible location
without requirement of removing or moving seat 14 or other structure. In an
illustrated
embodiment, tanks 80, 81 are aluminum and welded together. Tanks 80,81 may be
a structural
component as it may be possible that tanks 80, 81 could form part of frame 11.
In the illustrated
embodiment, tanks 80, 81 are generally horizontal and positioned between seat
14 and frame 11.
[0057] Tanks 80, 81 may be removable from frame 11, providing an operator to
remove the tanks for filling or replacement. A suitable latch or locking
mechanism could be
used to retain the tanks during operation. One or more handles may be
providing on the tanks to
facilitate transport during refilling, replacement, etc. Tanks may be
(optional) bolted
permanently to the frame or tunnel portion of vehicle
[0058] Control of the engine system, including air charging system, and
pressurized gas fuel regulation may be controlled by an electronic controller
100 receiving one or
more inputs relating to, for example, pressure, temperature, engine knock, and
emissions sensors.
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[0059] Other vehicles may utilize aspects of the present invention. For
example, a
personal watercraft (PWC) may include a power plant in accordance with the
present invention.
Similar to a snowmobile operation, a PWC operator straddles a seat during
machine operation.
Foot rests are provided on either side of the PWC seat. One or more fuel tanks
are provided
under the PWC seat. The tanks may be cylindrical and extend along the
longitudinal axis of the
watercraft. Alternatively, one or more fuel tanks may also be located in front
of bow or hull of
PWC. A propane powered turbocharged internal combustion engine would be used
to power the
watercraft. Location of the intercooler, turbocharger, etc. could vary
depending on the engine
dimensions, hull design, seat configuration, etc. In this embodiment, the
operator straddles the
propane tanks during use. One or more tanks could be utilized. Again, one or
more tanks could
be selectively removable from the hull to facilitate filling or replacement.
Suitable locking or
latch mechanism could be used to retain the fuel tanks within the PWC.
[0060] Fuel tanks may be positioned at any angle relative to the direction of
machine forward motion of the vehicle depending on the space constraints. For
example, a
plurality of gas tanks could be secured within the front hood of the
snowmobile. Alternatively, a
plurality of gas tanks could be secured underneath the operator seat. In one
example, the gas
tanks are aligned generally perpendicular to the direction of forward motion.
In other examples,
gas tanks could be positioned at other angles, e.g., vertical, etc.
[0061] Although the present invention and its advantages have been described
in
detail, it should be understood that various changes, substitutions and
alterations can be made
herein without departing from the spirit and scope of the invention as defined
by the appended
claims. Moreover, the scope of the present application is not intended to be
limited to the
particular embodiments of the process, machine, manufacture, composition of
matter, means,
methods and steps described in the specification. As one of ordinary skill in
the art will readily
appreciate from the disclosure of the present invention, processes, machines,
manufacture,
compositions of matter, means, methods, or steps, presently existing or later
to be developed that
perform substantially the same function or achieve substantially the same
result as the
corresponding embodiments described herein may be utilized according to the
present invention.
Accordingly, the appended claims are intended to include within their scope
such processes,
machines, manufacture, compositions of matter, means, methods, or steps.
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