Note: Descriptions are shown in the official language in which they were submitted.
CA 02594138 2007-07-19
METHOD AND APPARATUS FOR ENHANCED ENGINE ASPIRATION
FIELD OF THE INVENTION
The present invention relates to continuous self sustaining systems for the
enhanced
operation and performance of internal combustion engines.
BACKGROUND OF THE INVENTION
Engine power is directly related at least in part to the "breath-ability" or
"aspiration" of
combustible air optimally available for induction into the engine's cylinders
via the air
cleaner and intake manifold in an efficient manner. Conventionally, air is
drawn into
the cylinders by ambient air rushing in to replace negative pressure or vacuum
generated by each of the engine's piston's during their respective intake
stroke, with
the rate of induction being controlled in part by a number of factors. These
include
intake manifold design and related passage of air flow phenomena therein,
intake
valve timing (cylinder/intake runner back pressure due to valve overlap timing
considerations), additional intake runner back pressure pulsations due to high
dynamic ram effect of the incoming fresh air/fuel charge rebounding off the
back
intake valve fillet at closure, pressure differentials between the cylinder
and that of the
intake manifold which lags the throttle air flow, the speed determining
positioning of
the throttle valve assembly in a carburetor or other mechanism for admixing
fuel and
air, the quality, type and construction of the air filter and filter medium
and the
condition of the air filter medium porosity due to accumulated contamination
from air
born dust and debris, which is parasitic to the design aspiration
characteristics of the
medium.
In recent decades, carburetors have been replaced by electronic fuel injection
systems on OEM vehicles but the method of air intake remains substantially the
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CA 02594138 2007-07-19
same, with both carburetted and fuel injected engines described as being
normally
aspirated.
To improve performance significantly, forced induction systems have been used
that
greatly increase the amount of the combustible fresh air charge entering the
intake
manifold en route to the cylinders. The two principle forced induction systems
in use
are supercharging and turbocharging. Both systems use a turbine to pressurize
the
flow of air to the cylinders, the supercharger being driven directly from the
engine's
crankshaft, and the turbocharger using the flow of the engine's exhaust gas.
Both systems are highly effective but add significantly to an engine's cost.
They
typically require the use of higher octane fuel, more frequent regular
maintenance,
and numerous additional engine modifications to withstand the forces created
by the
enhanced engine output. As well, whereas superchargers continually provide
boost
at all engine speeds, they are typically associated with increased high
frequency
engine noise, which can be intrusive. Turbochargers are most effective at
increased
engine speeds when sufficient exhaust gas flow is available to drive the
turbine fast
enough to generate air intake boost. There can be therefore an undesirable lag
between the time the throttle is opened, and the time at which the turbo boost
takes
effect.
Because of the costs and other considerations, super and turbocharging have
been
largely confined to higher end performance engines of cars and heavy work
vehicles,
inclusive of industrial, marine and agricultural engines etc, which require
the extra
power. However, the present invention can be applied to turbocharged engines
to
assist in reduction of the aforementioned "lag" in turbo "spool-up" time.
Other means of improving air flow include the use of "air dams" to increase
cubic
capacity of OEM fresh air intake systems positioned downstream of the air
cleaner
and the throttle valve(s). These systems provide for a "gulping" of stored
post filtered
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CA 02594138 2007-07-19
air by the engine when required during acceleration. Additional innovations
include
after market multiple throttle valve assemblies and specialty intake
manifolds, now
appearing as standard equipment on many OEM engines that are "fine tuned" to
optimize inducted air flow. While these components are also effective, they
are again
an added high cost component and performance option and have therefore been
largely restricted to higher performance vehicles and the high end "tuner"
after
market.
High flow air cleaners are effective in their delivery of more air but they
eventually
clog with dirt and dust to gradually constrict and erode effectiveness of
porosity to
their air filtering intake which can have an adverse impact upon engine
exhaust
emissions, namely hydrocarbons (HC) as unburned fuel and carbon monoxide (CO)
due to fuel enrichment of the air/fuel ratio. Again, as with the preceding,
the relatively
high cost, and natural inclination of most car owners to avoid after market
products
that might affect engine life, have restricted their use.
SUMMARY OF THE INVENTION
The present invention seeks to provide a continuous self-sustaining system for
the
enhanced operation and performance of internal combustion engines, more
particularly a method and apparatus for alleviating the "lag" time in delivery
of
combustible air supplied to the engine's cylinder(s), especially at wide open
throttle
(WOT).
According to the present invention then, there is provided a method for
increasing the
quantity of combustible air supplied to the cylinders downstream of the intake
manifold throttle plate(s) of an internal combustion engine comprising the
steps of
directing air from the engine's crankcase to an air storage vessel; and
directing the air
from said storage vessel to the engine's cylinders for combustion.
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According to another aspect of the present invention, there is also provided
an
apparatus for increasing the quantity of combustible air supply to the
cylinders of an
internal combustion engine comprising an air storage vessel for the storage of
a
predetermined volume of air, said vessel having an inlet in fluid
communication with
said engine's crankcase for the inflow of air from the crankcase into said
vessel and
an outlet in fluid communication with said engine's cylinders for combustion
for the
flow of said air to the cylinders.
According to yet another aspect of the present invention, there is provided a
shuttle
valve for controlling the flow of a fluid therethrough, comprising a valve
body having a
cylinder formed therein, a fluid inlet port and a fluid outlet port, both of
which
communicate through said valve body with said cylinder; a piston arranged for
reciprocating movement in said cylinder, said piston having first and second
spaced
apart orifices formed transversely therethrough, said first orifice being
sized to permit
a first flow of fluid therethrough and said second orifice being sized to
permit a second
greater flow of fluid therethrough; actuating means for moving said piston
between a
first position in which said first orifice is placed in fluid communication
with said fluid
inlet and outlet ports and a second position in which said second orifice is
placed in
fluid communication with said first and second ports.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will now be described in greater detail and will be
better
understood when read in conjunction with the following drawings in which:
Figure 1 is a diagrammatic representation of an internal combustion engine
including
a discreet air storage vessel;
Figure 2 is a side elevational cross sectional view of an air storage vessel;
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CA 02594138 2007-07-19
Figure 3 is a perspective view of a modified storage vessel including a multi-
functional
shuttle valve assembly;
Figure 4 is a side elevational cross sectional view of the upper end of
modified
storage vessel of Figure 3 showing the multi-functional shuttle valve
assembly;
Figure 5 is a side elevational cross sectional view of the modified storage
vessel
showing the shuttle valve assembly in a different operative position;
Figure 6 is a front elevational view of a discrete shuttle valve that can be
used in
combination with the storage vessel of Figure 2;
Figure 7 is an exploded view of the shuttle valve of Figure 6;
Figure 8 is a side elevational view of a piston forming part of the shuttle
valve of
Figure 7;
Figure 9 is a side elevational view of the shuttle valve of Figure 6 in a
first operative
position;
Figure 10 is a side elevational view of the shuttle valve of Figure 9 is a
second
operative position;
Figure 11 is a perspective exterior view of the storage vessel including an
optional
mounting bracket; and
Figure 12 is a side elevational cross sectional view of the storage vessel
including an
internal partitioning baffle.
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DETAILED DESCRIPTION OF THE INVENTION
The present invention provides enhanced engine aspiration and improved
volumetric
efficiency of an engine's intake manifold at various throttle settings. By
extension, the
swept volume of the cylinder(s) during the intake stroke is also optimized.
The
benefits of the present invention are particularly noticeable when the engine
is under
continuous heavy load e.g. wide open throttle (WOT).
These dynamics are achieved through the harnessing of fluid mechanics common
to
engine operation. Namely a positive to negative pressure flow which occurs
within
the engine, the positive pressure originating within the engine's crankcase
and the
negative low pressure occurring within the intake manifold during engine
operation.
Through utilization and manipulation of pressurized crankcase emissions flow
that
are, due to environmental clean air considerations, currently returned to the
engine's
cylinders via the Positive Crankcase Ventilation (PCV) system and intake
manifold for
eradication within the combustion process, the volume and speed of this flow
can be
harnessed to enhance engine aspiration, piston speed, torque and performance.
During engine operation the pressure that originates and builds within the
crankcase
is due to piston ring/cylinder wall leakage, known as blow-by. The blow-by is
composed of inducted air/fuel mixture on the compression stroke and hot
gaseous by-
products of combustion on the power or combustion stroke. Some of these fluids
escape past the piston's sealing rings and cylinder wall into the crankcase.
Due to
the high speed pumping action of the pistons, pressure builds rapidly within
the
crankcase. Pressure increases exponentially as more throttle is applied until
maximum engine revolutions (RPM) are achieved at wide open throttle.
Conversely,
a simultaneous state of low pressure exists at WOT within the engine's intake
manifold due to ambient filtered air rushing to replenish the void being
generated
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CA 02594138 2007-07-19
within the cylinder(s) as the piston(s) begins to retreat at the commencement
of each
intake or induction stroke.
Therefore, the principle upon which this invention is predicated is that the
flow which
naturally occurs between these two dynamic opposing pressure zones, via the
PCV
system, can be manipulated to the engine's operational advantage.
This is accomplished through the ingestion of an instantaneous voluminous
release of
a regulated, continuous and sustainable flow of combustible air from a storage
vessel,
the air being supplemental to that of the incoming fresh air charge inducted
through
the air filter, the throttle valve assembly and the engine's intake manifold.
For
engines that are not computer controlled or that lack an oxygen sensor, the
supplemental air is supplied from an air storage vessel that is between the
PCV valve
and the engine's intake manifold. This will be described as being on the
downstream
side of the PCV valve.
In the present invention the supplemental air is introduced in a less
restrictive manner
that overcomes and/or alleviates time lag problems associated with inducted
air flow
through the air cleaner and the mechanical constriction of the throttle valves
and
intake manifold itself as discussed above. Similarly, at WOT, as engine load
increases, RPM's decrease, further reducing and slowing the manifold's
intrinsic
supply of incoming fresh air to the cylinders. The supply of supplemental air
provided
by the present method and apparatus assists in overcoming this dynamic
downturn.
In the case of modern engines controlled by an on board computer, the present
apparatus should preferably be invisible to the computer during normal engine
operation (defined as idle to intermediate engine RPM's) so as not to
destabilize
stoichiometric engine air/fuel ratios and/or intake manifold calibrations,
including
disruption to PCV valve operation. As will be described below, to maintain
this
invisibility when the air storage vessel is located downstream of the
crankcase vent
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CA 02594138 2007-07-19
(with PCV valve removed if desired), the vessel's cap can include a vacuum-
actuated multi-functional shuttle valve (MSV) assembly providing an
independent
dual flow characteristic that governs the desired flow of air exiting the
storage vessel
to the intake manifold at both WOT (nil vacuum), and at idle to intermediate
engine
RPM's (vacuum) ensuring overall computer managed efficacy of engine operation
at
differing power requirements. If preferred, the MSV can be a discrete
component
located between the air vessel and the intake manifold.
To avoid destabilizing the stoichiometric air/fuel ratios, the internal cubic
capacity
(CC) of the conduits connecting the MSV to the intake manifold should
correlate as
closely as possible to the internal cubic capacity (cc) of the original
equipment
manufacturer's (OEM) PCV valve's communication conduit which connects the PCV
valve to the engine's intake manifold.
Hence, when calibrating precise measurements for stoichiometric air fuel
ratios,
these cumulative volumes should preferably be as equal as possible so that no
additional air is detected by the engine's sensors and therefore visible to
the OBC.
Alternatively, the exhaust nipple on the MSV can be externally threaded (male
thread) so as to be screwed directly into the manifold.
The shuttle valve can be a discrete component or integrated into the vessel's
cap for
convenient operation and installation.
It should be noted that in this alternative, air does not necessarily have to
be sourced
from the engine's crankcase via its PCV system to achieve the improved supply
of air
to the cylinders in accordance with the present invention. Another method
would
involve having a remote ancillary air manifold/vessel with at least one high
flow
medium ambient air filter. The apparatus could be similarly screwed into the
engine's
intake manifold with the exception that the shuttle valve would require only
one orifice.
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CA 02594138 2007-07-19
The valve would therefore be configured with a large pressure sensitive "dump"
flow
orifice only, which will be described in more detail below.
Turning now to the specifics, Figure 1 shows a conventional engine layout
provided
with the inventive system, including a negative-pressure-resistant air storage
vessel
230. Vessel 230 is used to supply the engine's intake manifold 124 with an on
demand instantaneous flow of non-parasitic supplemental air, particularly at
wide
open throttle (WOT). The flow is governed by the positive crankcase
ventilation (PCV)
valve 31 flow calibrations or by a vacuum or electronically controlled shuttle
valve 400
(Figure 3) in response to fluctuating changes in intake manifold pressure
which occur
at varying engine operating loads and throttle settings. The engine shown in
Figure 1
is a push rod, carburetted engine. The present invention however is equally
suited for
use with fuel injected, overhead cam and computer managed engines,
irrespective of
fuel type. Any of these engines can be naturally aspirated or turbo or
supercharged
and may be gasoline, diesel, ethanol, methanol, biodiesel or alternative fuel
types.
An OEM (Original Equipment Manufacturer) or engine designer/manufacturer is
able
to easily match or calibrate the present apparatus as standard equipment,
optimizing
its benefits to improve engine power and performance at or near WOT. This
should
include a suitably calibrated transmission.
As shown in Figure 1, engine 10 includes a crankcase 20, a supply route 80
which
supplies filtered air to crankcase 20, an oil return / valve train gallery 100
that
channels crankcase emissions to the interior of a valve cover 30 and a PCV
valve 31
on the valve cover that connects to a negative pressure resistant conduit 110
that
directs crankcase emissions to air storage vessel 230.
The gases from crankcase 20 are forced by positive crankcase air pressure
through
PCV valve 31, into conduit 110 in the direction indicated by arrow A. The
conduit
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CA 02594138 2007-07-19
preferably has an enlarged inner diameter (I.D.) in the range of 0.5 inches
for
maximum non-restrictive fluid flow to the inlet of vessel 230.
The use of conventional conduits having a smaller I.D. although usable could
preclude achieving a preferred high volumetric gas flow and could constitute a
restricted, less voluminous flow.
A second conduit 120, having similar characteristics to conduit 110, is a
return conduit
for air flow from air storage vessel 230 to engine inlet nipple 122 on intake
manifold
124 in the direction of arrow B. PCV valve 31 is typically a variable flow one
way
check valve that allows air flow only in the direction of arrow A. This
prevents any
reverse flow of a burning air/fuel mixture into crankcase 20 in the event of
an engine
backfire inside manifold 124. Conduit 120 can be a single conduit that
delivers air to
a single or common plenum communicating with each of the manifold's intake
runners. Optionally, multiple conduits can be configured for air delivery to
individual
intake runners.
The ultimate length and inner diameter of each of conduits 110 and 120 can be
"tuned" for optimal performance. The conduits will ideally promote as little
restriction
to air flow as possible without at the same time being so large that they add
significant
uncalibrated capacity to the intake manifold at normal engine operating speeds
which
upset the engine's computer calibrated air/fuel rations. As mentioned above,
its
preferred that their volume equal as closely as practically possible the
original volume
of the OEM conduit between the PCV valve and the intake manifold.
In the present description, vessel 230 is described as being mounted
externally of the
engine and in communication with inlet nipple 122 of intake manifold 124. It
is
contemplated however that the vessel could be internally installed, such as
within the
valve cover itself, and communication with the crankcase could be provided by
a
different connection point such as a dedicated check valve or coupling on the
engine
CA 02594138 2007-07-19
block, for example. It is further contemplated that the air vessel could be an
engine
component,as an integral part of the intake manifold or a sub-system provided
by the
original equipment manufacturer (OEM) and/or specialty engine performance
component manufacturers.
As seen in Figure 2, vessel 230 can be a very simple and inexpensive enclosure
manufactured from any negative pressure resistant material such as metal,
nylon or
reinforced polymer (plastic). Vessel 230 can be as simple as an enclosure
including a
main housing 231 with a closure cap 233 securable to the open top of housing
230 by
means of threads 234. To ensure negative pressure integrity and to prevent
evacuated crankcase moisture buildup between the threads of vessel and those
of
cap 233, which would freeze in colder climates, causing expansion and possible
damage to the apparatus, an 0-ring 232 provides fluid tight sealing between
housing
231 and cap 233.
Closure cap 233 has an entrance inlet nipple 210 with an entering venturi 212
for
connection to conduit 110 in communication with PCV valve 31 located on valve
cover 30. Cap 233 also includes an exhaust or exit nipple 216 with an internal
venturi
214. This nipple is connected to conduit 120 and permits supplemental air from
vessel 230 to be directed back to the engine induction inlet 122 on intake
manifold
124 as seen most clearly in Figure 1. In place of a standard PCV valve, an
optional
reverse logic valve (not shown) which opens fully in response to a decrease in
manifold vacuum or is electronically opened in response to the angular
position of the
throttfe plate(s), as monitored by a throttle position sensor (TPS) allied to
computer
controlled engines, can be used to optimize the flow of air to the manifold
from vessel
230 and conduits 110 and 120.
Prior to engine start up, atmospheric or neutral pressure exists throughout
manifold
124 and air storage vessel 230. After start up, the engine's idle mode
generates high
negative pressure (vacuum) inside the intake manifold. The negative pressure
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CA 02594138 2007-07-19
communicates through inlet nipple 122 of the intake manifold 124 and conduit
120 to
air storage vessel 230 and then through conduit 110 to PCV valve 31,
establishing a
common stabilized pressure throughout the entire system of the apparatus. As
the
engine continues to idle, PCV valve 31 permits a continuous, calibrated low
flow of
about 1 to about 3 cu.ft. per minute, or about 0.03 to about 0.09 meters /
min., of
positive pressure crankcase gases to flow through conduit 110 to vessel 230
and from
there via conduit 120 to intake manifold 124. In response to the dissipation
of vacuum
within the intake manifold 124 at WOT, PCV valve 31 idle-flow calibration
automatically increases the flow to about 3 to about 6 cu. ft./min., or about
0.09 to
about 0.17 cu. meters / minute. This increase provides for greater ventilation
of high
pressure piston blow-by gases being pumped into crankcase 20 which is
consistent
with engine operation at high rpm or at WOT.
The cubic capacity air available for operational purposes of vessel 230 is
typically
500m1 to 1 litre although smaller or larger capacities are contemplated for
differing
applications or when "tuning" vessel size for optimal performance. Additional
capacity
is preferably provided to accommodate liquid and solid fractions separated out
from
the crankcase emission flow. Allowing for example an extra litre for the
separated
contaminants, the overall cubic capacity of vessel 230 can be two litres or
more. This
will be dependent on the engine's state of repair, the operative climate in
which the
engine operator and other f actors that can affect the amount of contaminant
in the
flow of crankcase emissions.
The operation of the present system will now be described.
When in operation, with the almost instantaneous dissipation of vacuum within
intake
manifold 124 at or near WOT, and an inverse increase in crankcase (piston blow-
by)
pressure due to the high speed pumping action of the pistons, PCV valve 31 is
designed to automatically open to its full flow potential. WOT initiates an
almost
instantaneous mass evacuation or disgorgement of the present system's entire
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CA 02594138 2007-07-19
internal atmospheric or cubic air capacity downstream to the engine's
cylinders via
the intake manifold. This high speed mass ingestion provides a beneficial
supplemental parcel of air from vessel 230 to the engine's cylinders creating
a boost
which increases piston speed, initially on the intake stroke, culminating in
enhanced
engine power and performance. The consequential speedy mass evacuation of the
departing incumbent parcel of air from within vessel 230 generates a partial
vacuum
behind it to the extent that it expedites the influx of replenishing high
pressure
air/emissions from crankcase 20 into vessel 230 for a continuous sustainable
supply
of supplemental on demand air to the intake manifold and cylinders.
During continuous heavy engine operation, a continuum of air from vessel 230
is
constantly available for delivery to the pistons/cylinders. Less energy is
therefore
expended by the engine to ingest the incoming fresh air / fuel charge.
Moreover, due
to high engine piston speed and the finite time the intake valves are open,
together
with the time lag of incoming air flow due to the linear restrictions
discussed above,
the availability of the supplemental air assists to "load" the bottom of the
cylinder(s)
with additional air as the piston reaches its terminus at bottom dead centre
(BDC) of
its intake stroke, thereby improving the swept volumetric efficiency of the
cylinders.
This dynamic aids combustion to enhance engine power and performance during
increased fuel load (rich fuel mixtures) delivery required for heavy
acceleration and
heavy load conditions. Overall manifold volumetric efficiency to the
cylinder(s) is thus
markedly improved along with engine power and performance at WOT.
A sequential series of cooling processes helps reduce the temperature of hot
air/
emissions exiting the crankcase vent prior to, during and after exiting air
storage
vessel 230. In the first instance, air is cooled as it expands and passes
through
conduit 110. The air experiences a second cooling phase as it passes through
acceleration venturi 212 of inlet nipple 210 of vessel cap 233. Next, the air
cools as it
enters and expands into the interior of air storage vessel 230. These cooling
processes are replicated in the reverse order as the air returns to the engine
at inlet
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CA 02594138 2007-07-19
nipple 122 of intake manifold 124. Further, the multiple accelerations and
expansions
help rid the gaseous crankcase emissions flow of undesirable heavy
hydrocarbons,
fuel, moistures, and solid and liquid contaminants i.e. oil, water, fuel,
coolant and
sludge etc. to increase the air density and oxygen content which assists in
maintaining engine performance gains whilst simultaneously protecting the
metering
orifice of the shuttle valve (MSV) from contamination as will be described
below.
As mentioned above, its preferable to locate air vessel 230 downstream from
PCV
valve 31. The PCV valve is itself a restrictive element and it could therefore
actually
impede mass air flow between vessel 230 and manifold 124 if it were located
between
the two. However, if located downstream of PCV valve 31, vessel 230 will no
longer
be invisible to the vehicle's OBC, which could cause the computer to sense the
presence of additional oxygen and that would upset its operations,
particularly with
respect to maintaining correct stoichiometric air/fuel ratios.
To keep air vessel 230 substantially invisible to the OBC, a multi-function
shuttle
valve 400 (MSV) located between vessel 230 and manifold 124 can be used that
allows only a calibrated or metered amount of air through a small metering
orifice
equal or nearly equal to that which the PCV valve normally allows to flow at
idle and
low to intermediate RPMs. However, at WOT, the shuttle valve would move to a
full
flow orifice or "dump" mode to release the air in vessel 230 en mass to the
intake
manifold.
Figures 3 and 4 show a modified linear air storage vessel 330 incorporating a
vacuum
operated, spring assisted piston actuated multi-function shuttle valve (MSV)
400
integrated into the vessel's cap 333. The vessel is described as being
"linear" in that
inlet nipple 310 and exit or exhaust nipple 316 are at opposite ends of the
vessel
rather than both being located on the vessel's cap 333. This provides for an
enhanced "fluid flow" configuration. Nipple 310 and 316 can be axially aligned
or
axially offset from one another.
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CA 02594138 2007-07-19
Figures 4 and 5 are cross sectional views of valve 400 integrated into the
vessel's cap
333 . In this regard, cap 333 is formed with an external valve body or housing
401
having an exhaust nipple 316, a vacuum nipple 406 and an internal cylinder 402
having at least three ports 405, 410 and 415. Port 405 is a vacuum port which
places
one end 403 of the cylinder in fluid communication with a source of vacuum
pressure,
which can conveniently be either the interior of conduit 120 or intake
manifold 124
itself via a vacuum hose (not shown) that connects to nipple 406. If the
vacuum hose
is connected to the manifold, the manifold will require a separate nipple for
this
purpose. If the hose connects to conduit 120, its been found preferable if it
taps into
the conduit at least a few inches downstream from nipple 316, or closer to the
intake
manifold than to nipple 316. Port 410 functions as both an outlet port to
vessel 330's
departing gases and an inlet port into cylinder 402. Axially aligned exit port
415 of
cylinder 402 functions as the outlet port for air exiting valve 400 and an
inlet port into
conduit 120 via exhaust nipple 316.
Valve 400 includes a piston 430 sized to closely fit into cylinder 402 for
reciprocating
movement therein. The top of piston 430 is narrowed in diameter to form a boss
431
which concentrically engages and spots an expansion spring 438 located between
port 405 and boss 431 in the head of cylinder 402. The outer end of spring 438
bears
against a steel washer 439 paired with a neoprene washer 440. Under the
influence
of vacuum pressure from intake manifold 124 communicated through port 406,
piston
430 is drawn to the left in Figure 4, compressing spring 438 in the process.
The
maximum amount of movement to the left is limited by contact of boss 431 with
washers 439/440. As vacuum dissipates at or near WOT, spring 438 will bias the
piston away from port 405 to the right as seen in Figure 5.
Piston 430 is formed with three (3) orifices 441, 445 and 450. The two primary
orifices 445 and 441 are spaced apart flow orifices which are formed to extend
transversely through the piston. The first orifice 445, located nearest boss
431, is
CA 02594138 2007-07-19
relatively larger in diameter by comparison to that of the second orifice 441
so that it
provides for the mass evacuation or dumping of the air from vessel 330 via
outlet
ports 410 and 415 and exhaust nipple 316 at WOT. The internal diameters of
linear
elements 410, 445, 415 and 316 are preferably the same to promote the fast
evacuation of air from vessel 330.
Second metering orifice 441 is a relatively smaller diameter metering orifice
whose
diameter is calibrated to allow a flow of air which is the same or
substantially the
same as the flow permitted in normal operation by PCV valve 31. The diameter
of
small orifice 441 can be made available in two or more different sizes for
engines of
different cubic capacities. A smaller available orifice can be sized to
accommodate
engines of up to, and including 2 (two) litres cubic capacity. A second
available orifice
can be sized to accommodate engines having a cubic capacity greater than 2
(two)
litres.
The third orifice 450 is a relief orifice. It's formed longitudinally through
piston 430 to
extend from orifice 445 to the piston's base or inner end 432, but without
intersecting
orifice 441. At or near wide open throttle, when the vacuum in manifold 124
dissipates, piston 430 should be quickly redeployed to the right in Figure 5
under the
influence of spring 438 to switch from metering orifice 441 to larger orifice
445.
Orifice 450 allows air otherwise trapped between the piston's base 432 and the
end of
cylinder 402 to escape harmlessly and quickly into orifice 445. Similarly, as
the piston
moves to the left in Figure 4 as vacuum in the intake manifold increases,
orifice 450
breaks the suctioning effect that would otherwise occur in the space between
piston
end 432 and the outer end of the cylinder.
At idle and low to intermediate RPMs, the vacuum inside manifold 124 is
sufficient to
draw piston 430 to the left in Figure 4 to compress bias spring 438 so that
metering
orifice 441 is axially aligned with cylinder housing orifices 410 and 415 and
exhaust
nipple 316 to allow a metered volume of calibrated air to flow from vessel 330
to the
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CA 02594138 2007-07-19
engine's intake manifold. However, at or near wide open throttle, the vacuum
in the
entire system collapses, and bias spring 438 returns piston 430 to the right
in Figure
5, which axially aligns the larger orifice 445 with cross flow orifices 410
and 415 for a
"dump" configuration allowing mass disgorgement of the vessel's contained air
to the
intake manifold to immediately increase the supply of combustible supplemental
air in
the engine's cylinders. Accordingly, at most engine speeds, the flow of air
from the
crankcase to manifold 124 is substantially the same as if vessel 330 were not
even
present so that it remains substantially invisible to the engine's on board
computer
(OBC).
Selectively piston 430 can be made of a light metal or reinforced plastic to
facilitate its
back and forth movement. It and spring 438 can be inserted through a removable
cap
434 that forms and seals the bottom of cylinder 402.
The shuttle valve provides the present apparatus and the engine with benefits
including:
1. The valve fully opens at WOT (nil manifold pressure / vacuum) for mass
disgorgement or "dumping" of air from vessel 330 into the intake manifold;
2. At the higher vacuums prevalent at all other throttle power settings, the
valve
shifts to a smaller metering orifice for reduced flow characteristics to
provide for
overall efficient engine operation, including WOT if required as a fail safe;
3. When vessel 330 is an external (retrofit) add-on component in communication
with the intake manifold, the valve's metering orifice 441 shields the
vessel's volume
from the sensors of the engine's on board computer other than at WOT; and
4. The valve provides harmonization with the inherent design flow
characteristics
of the vehicle's normal PCV valve operation.
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CA 02594138 2007-07-19
For enhanced operation and optimal performance, air can be evenly distributed
to
individual intake runners via a discrete manifold means or similarly between
individual runners as desired. There can even be a separate vessel 330 for
each of
the engine's cylinders. The use of the present invention improves initial
engine
piston speed and power output by delivering an instantaneous parcel of
unrestricted
combustible supplemental air at the commencement of the piston's intake stroke
especially at or near WOT. Linear downstream advantages include:
1. Immediate dynamic effect of increased inward or downward travel speed of
the recipient piston(s);
2. Intensification of "filling" or "loading" at the bottom of the intake
stroke with
supplemental combustible air as the piston reaches Bottom Dead Centre (BDC) of
the intake stroke, assisting in optimizing or improving overall cylinder swept
volume;
3. Carburetted, throttled body or direct injection engine fuel delivery
systems are
(or can be) calibrated to deliver enriched fuel mixtures at WOT conditions;
the
addition of supplemental air is conducive to enhanced combustion culminating
in
improved engine horsepower and torque generation;
4. As the fuel is subjected to more complete combustion, there is a reduction
of
unburned hydrocarbons (HC) (fuel) and carbon monoxide (CO) and particulate
matter exiting the engine's exhaust as atmospheric pollutants; and
5. Sustained assistance to manifold aspiration in respect of eroded air/ fuel
ratio
and engine emissions due to fouling of the air cleaner element by dust and
debris.
6. A continuum in the supply of combustible supplemental air prolongs piston
speed (RPM) under increasing engine load, as opposed to normal declining RPM
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CA 02594138 2007-07-19
which is consistent with the dissipation in the speed of the engine's linearly
inducted
fresh air charge.
The shuttle valve can be implemented in different ways.
For example, if preferred, the shuttle valve can be a discrete component not
incorporated into or as part of vessel 330. Reference is now made to Figures 6
to 10
showing a discrete vacuum operated, gravity assisted shuttle valve 600.
With reference to Figure 6, valve 600 includes a valve body 601 formed with an
integral entry nipple 614 for connection in fluid communication, such as by
means of
a conduit (not shown) with air vessel exhaust nipples 216 and an exhaust
nipple 616
that connects with downstream conduit 120 for the flow of air in the direction
of arrow
"A" from vessel 230 (Figure 1) to intake manifold 124.
The upper end of the valve body is formed with a male threaded bushing 606 for
connection to a female threaded screw-on nipple 607. A rubber or neoprene
backed
metal washer 608 (Figure 7) seals between nipple 607 and bushing 606. Nipple
607
is adapted for connection to a vacuum line (not shown) that delivers vacuum
pressure to the shuttle valve from manifold 124.
As most clearly seen in the exploded view of Figure 7, cylinder 602 is formed
inside
main valve body 601 to closely receive piston 630 for up and down
reciprocating
movement therein. Piston 630 is substantially identical to piston 430
described
above in relation to the embodiment of Figures 3 to 5, including having a
metering
orifice 640, a larger diameter orifice 645 and a relief orifice 650.
Since the piston in each of the embodiments described above is cylindrical and
subject therefore to rotation within the piston chamber, which would misalign
the flow
orifices through the piston with the openings in the vessel cap/valve body,
it's
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CA 02594138 2007-07-19
preferred to include some sort of anti-rotation restraint to the piston.
Numerous
ways of doing this will occur to the person skilled in the art, including a
splined
connection between the piston and cylinder wall, but as seen most clearly in
Figure
8, piston 630 is formed with a flat 631 on one of its faces offset at 900 to
orifices 640
and 645. Valve body 601 includes an opening 651 (451 in Figure 3) for a set
screw
652 having a flat machined end face 653 that projects sufficiently into the
cylinder to
oppose flat 631 in close enough proximity to negate piston rotation and
orifice
misalignment.
In operation, at low to intermediate RPMs, with valve 600 installed
vertically, the
vacuum communicated through nipple 607 pulls piston 630 to the top of cylinder
602, axially aligning small metering orifice 640 with inlet nipples 614 and
exhaust
nipple 616 as shown most clearly in Figure 9 to allow a metered calibrated
flow of air
from vessel 230 to intake manifold 124. However, at or near WOT, the vacuum in
manifold 124 collapses, releasing the suction to the shuttle valve so that
piston 630
gravitates downwardly to axially align large orifice 645 with nipples 614 and
616 as
shown most clearly in Figure 10 for a disgorgement or dumping of the air in
vessel
230 to intake manifold 124.
As will be appreciated by a person skilled in the art, its possible to adapt
the shuttle
valve for mechanical or electrical operation as opposed to using vacuum
(negative)
pressure as a means to bias the piston, so the valve need not be mounted
vertically.
For example, if piston 630 is moved by a spring, a motor or any other
"proactive"
means, the valve can be mounted at any angle, even upside down.
It's contemplated as well that the shuttle valve may in some instances be able
to
replace the OEM PCV valve altogether. If the incumbent PCV valve is removed
from
its current position, say in the valve cover, and the shuttle valve inserted
in its place,
vessel 230's function as an atmospheric storage vessel could be replaced by
that of
the internal environs (cubic capacity) of the engine. However, this
configuration, if
CA 02594138 2007-07-19
used, might result in excessive contaminated crankcase emissions migrating at
WOT
downstream to the engine intake manifold.
Alternatively, a more desirable alternative to the preceding, would be
achieved by
coupling the MSV's exhaust nipple 616 as close as possible to the intake
manifold's
inlet nipple with a short section of suitable conduit and hose clamps. A
similar,
although longer, conduit would then communicate crankcase flow between inlet
nipple
614 of the MSV and the crankcase vent, which previously accommodated the PCV
valve.
In the alternative, exhaust nipple 616 can have an external (male) thread
applied,
which then may be screwed directly into a matching (female) threaded aperture
strategically placed in manifold 124. The redundant intake manifold nipple can
be
effectively sealed with a rubber vacuum cap or something similar. In this
configuration, to prevent excessive contaminating crankcase emissions from
degrading the fresh air/fuel charge and critical engine components and
processes, it
is advisable to attach air storage vessel 230, inclusive of optional emission
separation elements, to the MSV's inlet nipple 614. Nipple 614 would therefore
be
connected to air storage vessel's outlet nipple 216 via conduit 120, and inlet
nipple
210 of the air storage vessel would be connected via conduit 110 to the
crankcase
vent which formerly housed the PCV valve.
Figure 12 shows an additional modification to vessel 230 to include an
internal
partition 218. The partition directs the inflow of crankcase emissions through
a
majority of the interior volume of the vessel before flowing out from the
vessel to the
engine's cylinders via the intake manifold. The partition is preferably a
baffle
substantially parallel to housing 231 with a length preferably at least half
as long as
housing 231 and of course shorter than the total length of the housing. The
gap 219
beneath the baffle enables the air to move through the majority of the
interior volume
of the vessel before exiting nipple 216. Diverting the emissions flow in this
way allows
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CA 02594138 2007-07-19
the emissions to cool which increases their density and can prompt separation
of
contaminants.
Vessel 230/330 can be opened periodically for cleaning but otherwise requires
no
ongoing maintenance nor does it require any disposable or replaceable
filtering,
contaminant separating, or cleaning elements, although such elements are
optional.
The entire system is therefore economical to manufacture. The system is easy
to
install as an "after market" product. A person with basic mechanical skills
can easily
achieve this task.
Ideally, the inner diameters of nipples 122, 210, 216, 310, 316, 614 and 616
are
conformed or tuned to the characteristics of conduits 110 and 120. If the
inner
diameter of conduits 110 and 120 are 0.5 inches, the inner diameter of the
nipples
can be .375 inches/9.525 mm but this is not limitative.
The system of the present invention is essentially a sealed system that
ingests only
calibrated gases from the crankcase via the PCV valve. With the exception of
the
shuttle valve opening at WOT, the system remains invisible to the engine's
computer
management system and does not disrupt design calibrations of the engine's
intake
manifold or stoichiometric air-fuel ratios.
Vessel 230 can include an optional bracket 205 for mounting the vessel inside
the
engine compartment, as seen in Figure 11.
The above-described embodiments of the present invention are meant to be
illustrative of preferred embodiments and are not intended to limit the scope
of the
present invention. Various modifications, which would be readily apparent to
one
skilled in the art, are intended to be within the scope of the present
invention. The
only limitations to the scope of the present invention are set forth in the
following
claims appended hereto.
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