U.S. patent application number 10/269664 was filed with the patent office on 2004-04-15 for method and apparatus for treating crankcase emissions.
Invention is credited to Knowles, Desmond.
Application Number | 20040069286 10/269664 |
Document ID | / |
Family ID | 32068840 |
Filed Date | 2004-04-15 |
United States Patent
Application |
20040069286 |
Kind Code |
A1 |
Knowles, Desmond |
April 15, 2004 |
METHOD AND APPARATUS FOR TREATING CRANKCASE EMISSIONS
Abstract
There is described an improved method for treating crankcase
emissions from an internal combustion engine, comprising the steps
of directing the emissions from the crankcase to an emissions
separator, subjecting the emissions in the separator to a series of
cleansing operations for removal of contaminants, directing the
flow of cleansed emissions through a one way check valve back to
the engine for combustion and collecting the separated contaminants
for disposal.
Inventors: |
Knowles, Desmond; (Orleans,
CA) |
Correspondence
Address: |
BERNSTEIN & ASSOCIATES, P.C.
6600 Peachtree Dunwoody Road, N.E.
Suite 495
Embassy Row 400
Atlanta
GA
30328-1649
US
|
Family ID: |
32068840 |
Appl. No.: |
10/269664 |
Filed: |
October 12, 2002 |
Current U.S.
Class: |
123/572 |
Current CPC
Class: |
F01M 13/04 20130101;
F01M 13/022 20130101; F01M 2013/0433 20130101; F01M 2013/045
20130101; Y02T 10/121 20130101; F02D 9/104 20130101; Y02T 10/12
20130101; F02M 35/10222 20130101; F02M 25/06 20130101 |
Class at
Publication: |
123/572 |
International
Class: |
F02B 025/06 |
Claims
Claimed is:
1. An apparatus for drawing fluid into the intake manifold of an
internal combustion engine, comprising: outlet means for the flow
of said fluid into said manifold; and means associated with said
outlet extending into said manifold to create a zone of low
pressure downstream of said means that draws said fluid into said
zone and thence said manifold.
2. The apparatus of claim 22 wherein said means comprise a
projection extending at least partially into said manifold.
3. The apparatus of claim 23 wherein said projection is situated,
in whole or in part, upstream of said outlet.
4. The apparatus of claim 24 wherein said outlet is formed to be
flush with an internal surface of said manifold.
5. The apparatus of any proceeding claim wherein said fluid
comprises treated emissions from said engine's crankcase.
6. A method of drawing a fluid into the intake manifold of a
internal combustion engine, comprising the steps of: providing an
outlet into said manifold for the discharge of said fluid
thereinto; creating a zone of relatively low pressure immediately
downstream of said outlet; and using said zone of low pressure to
draw fluid from said outlet into said manifold.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to an enhanced and self
sustaining system for the management of the internal combustion
engine's crankcase, crankcase emissions and engine lubricating oil,
more particularly a sequential method and apparatus for reducing
crankcase operating pressures, removing contaminates from the
crankcase, prolonging engine lubricating oil life and cleansing the
crankcase emissions flow, including a bi-functional remote
collector for residuals storage and maintenance of volumetric
efficiency for the inventive apparatus. Additionally, the invention
optimally relates to a method and apparatus to evenly distribute
the cleansed emission flow to the engine's intake manifold air
runners, and a method and apparatus to maintain an operable
negative pressure to the PCV system at wide open engine
throttle.
BACKGROUND OF THE INVENTION
[0002] Historically, engine lubricating oil efficiencies have been
bolstered at the production level by the introduction of specific
additives to the virgin oil. Engine oil is basically contaminated
and degraded by the following: a) engine piston(s) blow-by
(undesirable bi-products of engine combustion, a portion of which
escapes past the pistons and piston rings into the crankcase)
comprising fuel soot, partially burned and unburned fuel, steam and
various gases and acids; b) foreign liquids, abrasive silicones
(dirt), engine component wear particles and oil oxidation
by-products; c) the emulsification of the foreign liquids with
chemical elements common to the oil e.g., sulfur combines with
liquids and elevated engine temperatures to produce corrosive
sulfuric acid. The only form of management afforded to the oil in
this hostile environment is the physical inclusion of an oil
filter. Although the oil filter is effective in removing solids
from the oil, its inability to remove dilutants such as moisture
and acids leaves oil vulnerable to viscosity breakdown and eventual
loss of lubricity. Further, filters that become plugged with sludge
and other solids, force the filter by-pass valve to open, allowing
unfiltered oil to circulate to downstream engine components. Thus a
primary cycle of undue engine wear and over contamination of oil
commences. Problems generated are diverse in nature, however of
major concern in this instance is increased cylinder bore and
piston ring wear. Consequently, the percentage of piston blow-by
increases impacting a heavier than normal contaminant load upon the
crankcase oil which accelerates degradation. The problem has now
gone full cycle. Crankcase pressures increase accordingly and can
force oil past engine gaskets and seals. The condition also
facilitates the ejection of oil from the engine crankcase via the
aspiration conduit fouling the air cleaner, culminating in elevated
carbon monoxide emissions. Also oil is vented along with the
contaminated crankcase emission vapours, migrating via the PCV
system and engine intake manifold en route to the engine combustion
chambers, adversely fouling the combustion process. Again, this
results in undue component related wear and a higher percentage of
piston blow-by entering the crankcase. Relevant PCV problems will
be referred to later in this document. This phenomena continues to
compound itself with every engine revolution. Increased fuel
consumption; loss of engine power; elevated exhaust emissions and a
host of other engine operating problems result. An additional
compounding factor is the human element, and is a real world
problem, in that many owner/operators do not regularly change their
engine oil and filter as per OEM specified. They simply top-up the
engine oil, sometimes to excess. Resultant problems are similar in
nature to the aforementioned.
[0003] It has now been the law for approximately 40 years that
crankcase emissions from internal combustion engines must be
recirculated back to the engine's air-fuel induction system for
recombustion in the piston chambers. The return flow of the
emissions is normally through the oil return lines extending
between the crankcase and the engine's valve or cam covers, and
from the valve or cam covers through an external hose or tube to
the engine's intake manifold where the emissions are blended with
the air-fuel mixture from the carburetor/fuel injectors (in
normally aspirated engines) for delivery to the combustion
chambers. A positive crankcase ventilation (PCV) valve controls the
flow of crankcase emissions into the fuel-air induction system,
normally in response to engine running speeds.
[0004] The PCV (Positive Crankcase Ventilation) valve is usually
located in one of three engine locations: 1) at the engine
crankcase vent in the valve/cam covers; 2) in line with the return
conduit; or 3) screwed directly into the engine intake manifold.
The valve meters and blends the flow of contaminated crankcase
emissions into the engines air/fuel delivery system (intake
manifold) in response to existing negative pressures within the
manifold at various engine load requirements. The path of the
emissions from the crankcase via the PCV valve/system, intake
manifold and combustion chamber (where they undergo a change of
state) and partially re-enter the crankcase as piston blow-by, is
the secondary engine cycle of wear and contamination. The PCV valve
is also intended to arrest a dangerous back flow condition to the
crankcase that could arise as a result of an engine intake manifold
backfire. This could cause a crankcase explosion.
[0005] The source and nature of crankcase emissions is well known
and need not be discussed in further detail. Suffice is to say that
in addition to unburned and partially burned fuel and volatile
gases that are desirably recycled for combustion, the emissions
also include a number of entrained contaminants that, even if
combusted, are harmful to the engine or the environment or both. To
the extent that the contaminants are combusted, they are exhausted
from the engine as harmful pollutants. On the way in and out of the
engines combustion chamber(s) they impair the function of critical
engine components including critical emission controls such as the
oxygen sensor and catalytic converter(s). To the extent that the
contaminants are not combusted, they simply remain in the engine,
for example as efficiency destroying combustion chamber deposits,
jamming piston rings open, hindering their function or they
partially return to the crankcase where they contaminate the oil as
previously mentioned. As a consequence, this culminates in a loss
of lubricating efficiency, sludge build-ups and a host of other
problems that degrade engine performance, increase fuel
consumption, elevate exhaust emissions and shorten engine life.
These problems increase cumulatively over time and are the result
of the second cycle of wear and contamination originating within
the engine crankcase. The first cycle exiting the crankcase via the
oil filter by-pass valve and, the second exiting via the Crankcase
vent and PCV valve/system.
[0006] Prior art inventions involving superseded carburetted
engines have made a variety of attempts to recycle combustible
volatile matter in crankcase emissions through insertion of various
PCV system filtering devices, without also recycling the entrained
contaminants. Varying degrees of success were achieved in this
theatre of operations. However, due to their disposition between
the PCV valve and the engine intake manifold, many of these
inventions have been impractical and commercially unsuccessful.
This was due primarily to imbalances that arose to the design
calibrations of the intake manifold (air/fuel induction system) by
their devices. This had the adverse affect of increasing the cubic
capacity of the manifold, externally, which subsequently generated
imbalances to the air/fuel ratios, of which the manifold is
synergistic. As a consequence, either fuel efficiency or exhaust
emissions or both were compromised. As previously stated, some
devices attained limited success on older generation carburetted
engines, and the technology of the day utilized in the static
measurement of such fuel efficiency and exhaust emissions supported
this. However, in today's high-tech world and with the availability
of vastly advanced and sophisticated test models, procedures and
measuring equipment e.g., Environmental Protection Agency and the
Federal Test Procedure (EPA/FTP), which subjects the engine to a
variety of driving and load conditions on a chassis dynamometer for
testing, and is the only full and acceptable standard for measuring
true engine performance in relation to the subject matter, indicate
otherwise. Further, when attempts have been made to apply this
class of older technology to `state of the art` modern day computer
controlled engines, they have been found to compromise OEM related
fuel and exhaust emission efficiencies. The engine's oxygen sensor,
located in the exhaust manifold, detects the additional air from
the prior art devices and consequently additional fuel is injected
into the intake manifold to counter the imbalance.
[0007] For example, Bush in U.S. Pat. No. 4,089,309, describes an
open crankcase emission device that requires the use of an
auxiliary air intake structure 43 that draws outside ambient air
into the device for initial cooling of crankcase emissions. This
introduces uncalibrated oxygen into the PCV system which, as
previously indicated, is detected by the oxygen sensor utilized in
today's computerized engine management systems and causes the
system to inject fuel that is surplus to requirement. Bush, in a
later U.S. Pat. No. 4,370,971, abandons the previous system
configuration in favour of repositioning the system between the PCV
valve 27 and the intake manifold entry port 36. In doing so, Bush
not only retains the auxiliary air intake structure 69 with
attendant problems but also subjects the whole configuration to a
negative pressure environment. This, claims Bush, relates to
improvements in the control of crankcase emissions, without due
concern to the detrimental affects on the intake manifold design
and operation. Specifically, Bush's later configuration is now in
direct communication with the interior of the engine intake
manifold and unbalances the manifold calibrations by externally
increasing its cubic capacity. This avails additional oxygen to and
unbalances the stoichiometric air/fuel mixture within the manifold.
Again, this condition is detected by the engine's oxygen sensor,
and further confuses the computer which can only respond by
injecting additional fuel to counter the imbalance. Even therefore
if Bush removed and plugged the auxiliary air intake structure 69
to accommodate modern-day engines, his system's disposition would
still fail it.
[0008] A similiar approach is taught by Costello in U.S. Pat. No.
5,190,018 to that of Bush in U.S. Pat. No. 4,370,971. Costello's
device is similar in structure, operation and disposition to that
of Bush, with all the attendant disadvantages, including creating
an uncalibrated increase in the volume of the engine's intake
manifold.
SUMMARY OF THE INVENTION
[0009] A self sustaining crankcase management system capable of
removing contaminants from the crankcase, crankcase emissions and
engine lubricating oil is important to maintaining and protecting
OEM component and oil manufactures design efficiencies. These
corrective steps help preserve and prolonged fuel efficiency,
overall engine performance and exhaust emission standards. The
contaminant removal steps reduce the presence of foreign liquids,
reduce the formation of residual corrosives and negate the
existence of constituents to sludge buildup. The process would
further mitigate the existence of the primary and secondary cycles
of wear and contamination and allow uncombusted volatiles and
ketones to migrate beyond the crankcase management system to the
engine combustion chamber(s) via the PCV system and intake
manifold.
[0010] It is therefore an object of the invention to provide a
supplementary crankcase vessel having an internal crankcase
emissions separator that obviates and mitigates from the
disadvantages of the prior art.
[0011] It is a further object of the present invention to provide a
supplementary crankcase vessel that reduces and equalizes the
operating pressure of the crankcase thereby maximizing the
uninhibited removal of crankcase contaminants and emissions from
the crankcase. It is a further object of the present invention to
provide a supplementary crankcase vessel and separator which is
invisible to the engine's computer management system and which does
not disrupt the design calibrations of the engine's intake manifold
or stoichiometric air/fuel ratios.
[0012] It is a further object of the present invention to
optionally provide a remote bi-functional vessel to collect liquid
and solid residuals draining from supplementary crankcase vessel
and its separator to sustain their design efficiencies.
[0013] It is a further object of the present invention to provide
the aforementioned apparatus that operates under the influences of
positive rather than negative pressures.
[0014] It is a further object of the present invention to provide
optional apparatus which will provide an operable negative pressure
to the engine PCV system at wide open throttle condition. This
previously has not been an OEM engine design feature.
[0015] It is a further object of the present invention to provide
optional apparatus to the engine PCV system for even distribution
of cleansed crankcase emissions to individual air runners of the
intake manifold.
[0016] It is a further object of the present invention in a
preferred embodiment that it be adaptable to internal combustion
engines that consume gasoline, diesel, compressed natural gas
(CNG), propane (LPG), ethanol, methanol and all other forms of
fuels. Moreover, the broad principles of the invention can be
applied to the separator of contaminants from bulk fluids such as,
for example, the removal of water from compressed natural gas.
[0017] It is a further object of the present invention to provide
the aforementioned apparatus that is economical to produce and
install either as original equipment or as an after market
addition, and which is easily and readily serviceable.
[0018] According to the present invention then, there is provided a
method of treating crankcase emissions from an internal combustion
engine, comprising the steps of directing emissions from said
crankcase to an emissions separator; subjecting the emissions
flowing through said separator to a cleansing operation for removal
of contaminants; directing the flow of cleansed emissions through
one way check valve means back to the engine for combustion; and
collecting the separated contaminants for disposal.
[0019] According to the present invention, there is also provided
an apparatus for treating crankcase emissions from an internal
combustion engine, comprising a first housing having an inlet for
the inflow of crankcase emissions, an outlet for the return flow of
treated emissions to the engine for combustion therein and drain
means for drainage of contaminants separated out from said
crankcase emissions; a second housing disposed in said first
housing, said second housing including an inlet in fluid
communication with said inlet in said first housing, and an outlet
in fluid communication with both said outlet and said drain means
in said first housing; and treatment means disposed in said second
housing for subjecting the crankcase emissions flowing therethrough
to cleaning operations for separation of contaminants from said
emissions.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Preferred embodiments of 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:
[0021] FIG. 1 is a diagrammatic representation of an internal
combustion engine including the present separator;
[0022] FIG. 2 is a side elevational cross sectional view of the
separator
[0023] FIG. 3 is a top plan view of a velocity stack compression
head forming part of the separator;
[0024] FIG. 4 is a plan view of an annular screen forming part of
the separator;
[0025] FIG. 5 is a diagrammatic view of a negative pressure
generator located in an intake runner;
[0026] FIG. 6 shows the intake runner at wide open throttle
[0027] FIGS. 7 to 9 are diagrammatic views of alternative negative
pressure generators;
[0028] FIG. 10 is a side-elevational cross-sectional view of the
upper portion of the materials drained from the separator of FIG.
2;
[0029] FIG. 11 is a side-elevational partially cross-sectional view
of a gravity collector for draining the collector of FIG. 10;
[0030] FIG. 12 is a side-elevational cross-sectional view of a
modified separator;
[0031] FIG. 13 is a side-elevational cross-sectional view of the
upper portion of then separator of FIG. 12;
[0032] FIG. 14 is a side-elevational cross-sectional view of the
mid-portion of the separator of FIG. 12;
[0033] FIG. 15 is a top plan view of the velocity stack compression
head forming part of the separator of FIG. 12;
[0034] FIG. 16 is a side-elevational cross-sectional enlargement of
part of the separator FIG. 12; and
[0035] FIG. 17 is an upper perspective view of the exterior of the
separator of FIG. 12
DETAILED DESCRIPTION
[0036] With reference to FIG. 1, there is shown a conventional
engine layout coupled to the present separator 200 used for
separating crankcase emissions into liquid, solid and gaseous
fractions and for collecting the non-gaseous fractions while
recycling the gaseous fractions. The engine shown is a relatively
low tech push rod, carbureted engine, still in common use
particularly in fleet vehicles. The present invention however is
equally suited for use with more modern fuel injected, overhead
cam, computer managed engines.
[0037] Throughout the drawings, like numerals have been used to
identify the elements.
[0038] As shown, engine 10 includes a crankcase 20, an oil return
line 100 that channels crankcase emissions to the interior of a
valve cover 30 and a connector 35 on the valve cover for a conduit
110 that directs the emissions to separator 200.
[0039] The emissions are forced by positive pressure in the
crankcase into conduit 110. This conduit preferably has an enlarged
inner diameter (I.D.) for maximum non-restrictive fluid flow to the
inlet of separator 200. The use of conventional conduits having a
smaller I.D. would preclude achieving a preferred high volume
emissions flow and could constitute a restricted, less voluminous
flow. The second enlarged I.D. conduit 120 is a return conduit for
cleansed emissions. A third and smaller optional conduit 220
transfers filtered, precalibrated cooler non-ambient air,
selectively sourced downstream from the throttle valve/valves, to
an aerodynamically designed vortex generator and diffuser 222.
Conduit 220 may alternatively draw air upstream of the throttle
valve/valves and downstream of the mass air-flow sensor when one is
present.
[0040] In the following description, separator 200 is described as
being mounted externally of the engine and in communication with
the engine's crankcase through a connector in a valve cover. It is
contemplated however that the separator could be internally
installed, such as within the valve cover itself, and communication
with the crankcase could be provided by a different connection
point for example a dedicated check valve or coupling on the engine
block. It is further contemplated that the separator could be
constructed as an integral engine component or subsystem.
[0041] The separator 200 of the present invention is shown in
grater detail in FIG. 2 and includes a main housing 230 and a
cartridge 240 therein which preferably is consumable and
replaceable. A closure cap 233 is secured to the open top of main
housing 230 by means of threads 234. O-rings 237 and 238 provide
sealing between housing 230 and cap 233 and between shoulder 243 on
cartridge 240 and the cap, respectively.
[0042] Entering the closure gap 233 is a direction adjustable,
radiused right angle inlet port 210 with a concave venturi 212 for
receiving crankcase emissions. In one embodiment constructed by the
applicant, the inlet port 210 defines a diffusion chamber 216
intermediately downstream of its inlet. This diffusion chamber 216
can include a port 214 for the insertion and placement of a
diffuser 222. The diffuser includes an outlet 224 that allows
filtered, cooler non-ambient calibrated air from conduit 220 to
admix with the crankcase emissions as they flows past into
cartridge 240. An exit port 218 through cap 233, similar in
configuration to inlet port 210, permits cleansed portions of the
emissions flow to be directed back to the intake manifold of the
engine via conduit 120 and one way PCV check valve 126 seen most
clearly in FIG. 1.
[0043] Main housing 230 advantageously includes at its lowermost
end concave floor 235 which communicates with an exit drain 236
leading to a collection vessel 400. Inner wall 231 of main housing
230 includes a plurality of support brackets 238 for cartridge 240.
The brackets are spaced equidistantly about interior wall to
support the cartridge above floor 235. Main housing 230 may be
optionally elongated to compensate for the absence of a drainage
collector and/or drainage service unit as will be described
below.
[0044] Cartridge 240 separates/fractionates the incoming crankcase
emissions into liquid, solid and gaseous portions, the liquid and
solid portions being decelerated, condensed and separated both in
the cartridge and in a cassette 250 within cartridge 240 and then
drained away. Cleansed fractionated emissions are meanwhile
permitted to flow toward exit port 218 for exit from the housing
via enlarged conduit 120. As will be apparent, vacuum produced in
the intake manifold when the engine is operating, coupled with
positive pressure in the crankcase, causes the crankcase emissions
to be forced into separator 200. Venturi 212 formed in inlet port
210 accelerates the flow of emissions received from conduit 110.
Inlet venturi 212 also assists in maximizing the flow of crankcase
emissions from the crankcase through conduit 110, due to a slight
drop in temperature of the emissions as they pass through the
venturi.
[0045] As the emissions flow through inlet port 210, they then pass
into diffusion chamber 216. Disposed in this chamber is the
external, non-ambient air diffuser 222 with outlet 224. Diffuser
222 is located centrally in chamber 216 to ensure that the
calibrated non-ambient air from outlet 224 is introduced centrally
into the emissions flow, rather than permitting this air to flow
down the wall of the cartridge inlet conduit 242. To enhance this
function, diffuser outlet 224 is centrally located in the
diffuser's lower surface where it comprises a minute orifice. This
specific positioning in conjunction with turbulent vortices
generated downstream of the diffuser enhances the oxidization and
condensation of the emissions. Diffuser 222 is triangular in
transverse cross-sectional shape, with its apex pointed up into the
laminar flow of entering emissions. Laminar flow of emissions
passing around the diffuser will break up on both sides of the
diffuser, generating downstream turbulence and probably
inter-molecular collisions. Therefore greater kinetic energy is
produced via these generated turbulent vortices, to enhance cooling
of the emissions flow. As a result, heavy hydrocarbon and foreign
matter emissions are reduced to a liquid state, and pass through
vortex generator 244 to an expansion chamber 245 in cartridge
240.
[0046] Conduit 242 connects an upper venturi 243' with vortex
generator nozzle 244. Emissions passing through conduit 242 are
reaccelerated, straightened and marginally cooled. Vortex generator
nozzle 244 produces large turbulent flow vortices within the
emissions flow entering primary expansion chamber 245, enhancing
kinetic energy within the emissions flow.
[0047] Within separator 200 there are three expansion chambers: two
within cartridge 240, namely chambers 245 and 248; and one 258
within the removable cassette 250 that fits concentrically into
cartridge 240 and which will be described in greater detail below.
The number of chambers may however vary up or down and there is
described below an embodiment having four such expansion zones.
[0048] Primary expansion chamber 245 is bounded on its sides and
upper surface by the surrounding walls 246 of cartridge 240 and on
its lower surface by a solid circular conic baffle 251. Baffle 251
is the uppermost component of cassette 250 and is connected to the
cassette by means of a threaded connection 253 to a drain tube 259
that passes axially through the cassette's centre and acts as a
spine interconnecting the cassette's components. The baffle
generates reverse vortex motion back into the incoming emission
vortices generated by vortex generator nozzle 244. This results in
a first-stage separation of the emissions flow wherein undesirable
heavy hydrocarbons and foreign matter are removed from the
emissions flow by, it is believed, enhanced sidewall impingement
and the condensing effect of inter-molecular collisions within the
generated turbulent vortices. Baffle 251 also serves to protect the
cassette's downstream components from direct and excessive
contamination by the turbulent emissions flow entering chamber
245.
[0049] Condensates tend to form in oil and moisture droplets of
water, fuel, coolant,/anti-freeze, tar, varnishes and other
crankcase contaminants that drain down cartridge wall 246 and over
the lip 252 of baffle 251 to collect in the annular space 265
beneath the baffle and between the cartridge wall 246 and the
opposed wall 266 of the cassette. Further downward drainage is
prevented by O-ring's 268 that seals between the cartridge and the
cassette. Fluid that collects in this area flows into concentric
drain tube 259 via 2 or 3 radial drain lines 256 that open at one
end through cassette wall 266 and at the other end into the drain
tube. The placement of the radial drain lines can most easily be
seen from FIG. 3 which is a plan view of the cassette's upper
surface immediately below the baffle. The drain tube itself directs
the condensates to the bottom of the cartridge and from there the
residuals flow through drain 236 into a collector 400 (FIG. 1).
[0050] There follows a more detailed description of the elements
comprising the consumable/disposable cassette 250.
[0051] The basic elements of cassette 250 comprise, from top to
bottom, baffle 251, a venturied velocity stack compression head
254, expansion chamber 258, wire mesh screen 257, gas deceleration
and condensation element 261, and exhaust skirt 267.
[0052] Residual liquids condensed in expansion chamber 245 are, as
aforesaid, drained away through lines 256 and 259 and therefore
effectively by-pass the cassette, preventing it from becoming
overly gummed up.
[0053] Compression head 254 is situated beneath baffle 251 and is
separated from the baffle by a shoulder 253 on the baffle's lower
surface. The expanded emissions from chamber 245 flow into this
space and into a plurality of velocity stacks 255 formed through
the compression head. The placement of these stacks is best seen
from FIG. 3 where it will be seen that they are arranged to avoid
interference with radial drains 256. The velocity stacks themselves
are substantially funnel-shaped to compress the remaining emissions
flow. The emissions emerging from the stacks are then expanded
somewhat into expansion chamber 258 before flowing through wire
mesh matrix screen 257 located above deceleration and condensation
element 261. The screen provides a supplemental emissions
impingement surface for additional condensation of residuals.
[0054] Deceleration and condensation element 261 advantageously
comprises a primary packing of inert particles such as glass beads,
each being 3-4 mils in diameter. Preferably as well, a secondary
packing of smaller diameter glass beads, by comparison 2-3 mils in
diameter, interfaces with the primary packing to further decelerate
and condense undesirable heavy hydrocarbons and foreign matter from
the flow. The beads can be perforated and other particulates, or
fibres, can be used. This step is preparatory to the light
hydrocarbons and volatiles being fractionated from the heavy
hydrocarbons and foreign matter as the emissions emerge into
succeeding expansion chamber 248. By whatever process is involved,
it has been found that the passage of the emissions through the
glass beads results in significant additional separation of
undesirable liquid and solid fractions that drain through wire mesh
exhaust skirt 267 for eventual discharge into collector 400. It is
possible that the impingement of the emissions against the beads
generates greater entrainment of the liquid fractions, separating
these fractions from the vapour stage by deceleration and
condensation.
[0055] Packing 261 can also act as a flame arrester in the event of
an engine backfire through the intake manifold.
[0056] Cassette 250 terminates at exhaust skirt 267 which confines
the glass beads within the packing.
[0057] The remaining emissions flow from the packing enters
expansion chamber 248 where some additional condensation of heavier
residuals can occur, particularly as the emissions impinge against
cartridge wall 246. These residuals also drain through the open
lower end 249 of the cartridge for discharge into collector
400.
[0058] In operation contaminates are transferred to gravity
collector 400 through drain 236 of main housing 230 and the
remaining gaseous emissions flow travels around cartridge terminus
249 and upward between inner wall 231 of main housing 230 and the
outside wall of cartridge 240. Travel of the emissions through this
annulus 270 provides yet another opportunity for condensation of
undesirable residuals that flow back down the annulus to the bottom
of the separator for drainage.
[0059] In one preferred embodiment constructed by the applicant,
the lower end of annulus 270 is provided with a screen 271 (FIG. 4)
so that the annular space above the screen can be filled or
partially filled with additional glass beads 260. These beads can
rise or fall in the annulus depending upon the level of suction
induced by the engine's intake manifold acting through conduit 120.
This can maximize the exposure of their surface area to the
emissions for a final cleansing impingement.
[0060] The cleansed emissions exit separator 200 via exit port 218
and conduit 120 to the engine intake manifold 124 after passing
through PCV valve 126.
[0061] Within the entire assembly represented by the main housing
230, a vaporization effect of remaining volatiles is believed to
take place. This thermal vaporization is due to the insulating
characteristic of the main housing 230, relative to encased inner
cartridge 240 and cassette assembly 250. Heat is derived from the
convectional flow of hot engine crankcase emissions throughout the
assembly. From this convectional flow, heat is absorbed via
conduction of all exposed interior surfaces. This absorbed or
conducted heat facilitates, through radiation, the vaporization of
volatiles contained within the heavy hydrocarbons.
[0062] As is known, vacuum diminishes within an engine's intake
manifold at high engine speeds, particularly at wide open throttle
(WOT). At the same time, excess pressures will build up within the
crankcase, due to the high speed pumping action of the pistons.
Nonetheless, these pressures must somehow be vented and permitted
to escape. Otherwise piston blowby pressures will back up through
the crankcase aspiration conduit into the air cleaner, or air duct,
thus contaminating the air filter and/or downstream components. In
some cases, this condition creates a problem which causes
excessively rich mixtures, ultimately leading to the production of
undesirable tail pipe emissions. In addition, a further effect of
non-aspiration of the crankcase by cooler ambient air is engine and
engine lubrication heat stress. To date these problems have posed
difficult solutions to engine design and operation. There will now
be described a method and apparatus for negative pressure
generation in the engine intake manifold irrespective of throttle
opening.
[0063] FIG. 5 depicts a normal high vacuum condition in the intake
manifold at partially open throttle. As the throttle progressively
opens as shown in FIG. 6, vacuum diminishes, affecting the
operational efficiency of the PCV system. To overcome this problem,
a negative pressure generator 130 is introduced to the interior of
the intake manifold. This generator, which is the outlet into the
intake manifold for the cleansed emissions delivered through
conduit 120 from separator 200, produces a venturi effect at the
high dynamic flow rates prevailing at open throttle settings,
creating in effect a vacuum in its own wake. This draws in the
cleansed emissions to maintain operation of the PCV system and
ambient airflow throughout the engine crankcase at high engine
speeds. This negative pressure generating function is largely
inoperative and unneeded when vacuum exists in the intake manifold
at lower throttle settings. The resultant function of maintained
crankcase aspiration assists in cooling and preserving crankcase
lubricants and engine components under extreme operating load
conditions.
[0064] Alternative negative pressure generators 150, 160, and 170
are shown in FIGS. 7, 8 and 9 respectively, and their operation
will be apparent to those skilled in the art without further
detailed explanation.
[0065] As will be apparent, the separation and collection method
and apparatus described above will function independently of the
use of the negative pressure generators shown and described with
reference to FIGS. 5 and 9.
[0066] FIG. 10 depicts the details of gravity collector 400. It is
connected to drain 236 of main housing 230 by means of conduit 270
for collection and storage of removed contaminants. The gravity
collector 400 has an optional drainage service unit 500 (FIG. 11)
which may also be installed.
[0067] The function of collector 400 is not only to receive
residuals from separator 200, but also to maintain pressure
reduction and pressure equalization with the engine's crankcase. It
comprises a main housing 402 and a housing closure 404 threaded
thereto. O-ring 405 seals the housing and cap together. The
collector may be disposed horizontally or vertically in the engine
compartment, alongside the crankcase, sub-frame or wherever space
permits at an elevation below drain 236. Both inlet 406 and outlet
408 are offset from the center of the cap to facilitate access and
ease of installation of conduits 270 and 420 respectively in the
cramped quarters of the engine compartment and/or vehicle chassis.
Inlet nipple 406 protrudes inwardly into the container chamber. It
is of enlarged diameter, relative to outlet 408. Scavenge line 410
is open-ended permitting access to residuals, should the collector
400 be set horizontally. Gravity drain plug 412 is set on the
bottom, adjacent the scavenge line 410. Fluid level sensor 413 is
set within cap 404, whereupon it may correctly gauge the fluid
level whether the collector is set vertically or horizontally.
Conduit 420 being interconnected to scavenger line 410 via outlet
nipple 408 leads scavenged residuals from the collector 400 to
interconnecting nipple 604 of coupler 600.
[0068] The gravity collector 400 is provided with an ambient air
vent conduit 422 originating on coupler 600 at the ambient air vent
nipple 606. The nipple has a vent nipple cap 606'. In the collector
housing cap 404, the vent conduit 422 terminates in the cap at vent
nipple 414.
[0069] Connecting the collector 400 to portable drainage service
unit 500 is a check valve coupler 600. This coupler is positioned
on a header panel at the front of the engine compartment or wall
bracket and is provided with nipples 602-604. The former, nipple
602, services conduit 420 from collector 400 and the latter, nipple
604, connects conduit 520 to the succeeding drainage service unit
500.
[0070] With reference to FIG. 11, the housing 502 of service unit
500 is provided with a hermetically sealed cap 504 which contains a
check valve 508 and a vacuum source nipple 510, said nipple having
a dust cap 510'. Element 512 comprises a retractable dump spout
which is self-sealing under the influence of negative pressure.
Inlet nipple 506 of drainage service unit 500 is interconnected via
conduit 520 to nipple 604 of coupler 600. Outlet nipple 510 of
drainage service unit 500 is interconnected via conduit 530 to a
preselected vacuum source at the engine intake manifold to
periodically empty collector 400.
[0071] The basic method and apparatus herein may function
independently of the drainage service unit 500. Its inclusion is
optional.
[0072] Such a drainage service unit might not be adapted to diesel
engines as most lack an engine vacuum source but the collector 400
may be drained to the same effect.
[0073] Reference will now be made to FIGS. 12 to 17 showing the
preferred embodiment of the present separator which is somewhat
simplified in construction for more efficient manufacturing,
particularly if the unit is to be made from plastics. This
embodiment is, in its main features, the same as the embodiment
described above with reference to FIGS. 1 to 4 with the principle
exception being that cassette 250 is eliminated as a discrete
element and is instead integrated into cartridge 240 for a more
economical and simplified construction. The following description
is therefore limited to the more significant differences between
the two embodiments.
[0074] As will be seen particularly from FIG. 12, inlet port 210
and exit port 218 are straight, lacking the integrated elbows in
the inlet and exit ports of the separator shown in FIG. 2. Rather,
relatively inexpensive radiused elbows 195 can be used that can be
either friction fit or clamped to the ridged outer surfaces of
ports 210 and 218. This also allows the elbows to be turned in the
direction of conduits 110 and 120 to minimize unnecessary bends and
crimps in these lines. The inlet port may still enclose a diffuser
222 as best seen in FIG. 13, the diffuser being supported in a
cradle 227 located in the widened throat 228 of inlet 210. The
lower edge 229 of the cradle is camphered to nest into the
correspondingly camphered upper venturi 243'. Diffuser 222, if
present, provides the same function as described above although in
this embodiment, the diffuser is not adapted to discharge
calibrated air from the intake manifold into the emissions flow.
The triangular diffuser therefore merely generates turbulence. If
such air is to be introduced into the emissions flow, the diffuser
described above including outlet 224 can be substituted.
[0075] As described previously, the lower surface of expansion
chamber 245 is bounded by a conic baffle 251. In this embodiment,
the baffle shown most clearly in FIG. 14, displays greater pitch
along its sloped sides and is connected to the compression head 254
itself by a snap fit between sleeve 248 on the baffles' lower side
and a circular stem 249 extending upwardly from the head's upper
surface.
[0076] The purpose of the baffle is to generate reverse vortices
back into expansion chamber 245 to promote condensation of liquid
contaminants via collision. The condensates drain down inner walls
246, past the baffle's lip 252 and into the annular space 265
beneath the baffle and between cartridge wall 246 and the opposed
shoulder 266 of compression head 254. In this embodiment however,
O-ring's 268 are eliminated and instead, wall 266 is extended to
include a lower surface 266' so that annular space 265 is now a
self-contained trough extending completely around the upper
periphery of the compression head. Whereas in the previously
described embodiment, fluid from this space drained into a drain
tube 259 via radial drain lines 256, drainage has been considerably
simplified in this embodiment by forming two or three small holes
264 seen best in FIG. 15 in the trough's lower surface which allows
the condensates to continue draining down the inner walls 246 of
cartridge 240 towards drain 236. In this way, radial drains 256 and
drain tube 259 can be eliminated.
[0077] The top of wall 266 is bevelled as shown at 269 which, in
co-operation with the upward flare of lip 252 on baffle 251,
provides a peripherally extending conically-shaped opening or
venturi 279, shown diagrammatically in FIG. 14 by broken lines,
into an expansion area or chamber 275 between the baffle's lower
surface 276 and an upper surface 277 of compression head 254. There
is believed to be an acceleration, and a concurrent cooling, of the
emissions through opening 279 and then an expansion of the flow
into chamber 275 in which, at least ideally, an equal and steady
pressure is maintained over velocity stacks 255. The emissions flow
is then once again compressed and accelerated as it is forced
through the velocity stacks 255 into expansion chamber 258. This
rapid series of compressions, expansions and accelerations is
believed to promote separation of contaminants, particularly as
liquid discharge from the velocity stacks into chamber 258 can
sometimes be observed.
[0078] The function of the elements previously part of cassette 250
is substantially the same as described above with the exception
that the entire internal volume of the space 258 between skirt 267
and velocity stack compression head 254 is occupied by the packing
of inert articles such as glass beads. Compression head 254 is now
an integrated part of the cartridge 240 as seen most clearly from
FIG. 14, and skirt 267 snap fits into a circumferential notch or
detente 278 formed into cartridge wall 246 as shown most clearly in
FIG. 16. The beads can grade in size from 2 to 4 mls and can be
inter-mixed or layered with the larger particles at the top.
Advantageously, the beads can be perforated or made hollow to
increase their surface area for purposes of more graduated
deceleration of the heavy hydrocarbon and foreign liquids and
solids in the emissions flow.
[0079] When the packing fouls to the point of ineffectiveness, the
entire cartridge 240 can be removed and disposed of and a fresh
cartridge is installed in its place. In this embodiment, there are
four expansion chambers, numbers 245, 275, 258 and 248 proceeding
from top to bottom.
[0080] FIG. 17 is perspective view of separator 200's exterior
including a bracket 205 useful to mount the separator at a
convenient location in the vehicle's engine compartment.
[0081] Using the above described method and apparatus, one
scavenges the undesirable by-products of combustion and foreign
matter from the crankcase, before they are likely ingested into
engine crankcase oils. This creates a cleaner dirt- and acid-free
lubricant and environment. Emissions are purged from the crankcase
into separator vessel 230. The flow is thus directed through an
enlarged conduit, accelerated and passed through the separator,
wherein crankcase emission pressure is reduced by the addition of
external cubic capacity afforded by vessel 230 and contaminants are
separated by condensing and by induced vortex activity, by pressure
and temperature differential separation, expansion, collision,
induced fractionation, kinetic impingement and induced entrainment.
The heavy hydrocarbons and foreign matter are drained from the
separator into a separate gravity collector. The lighter
hydrocarbons and volatiles derived from the crankcase emissions are
rendered cleaner as a result of this overall process. These
cleansed hydrocarbons and volatiles comprise a more sophisticated
fuel which is now passed via a conduit advantageously to the
downstream side of the throttle valve ahead of the intake
manifold.
[0082] This is all accomplished in what is essentially a sealed
system that draws in no outside uncalibrated air.
[0083] The above-described embodiments of the present invention are
meant to be illustrative of preferred embodiments of the present
invention 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 out in the following appended claims.
* * * * *