Note: Descriptions are shown in the official language in which they were submitted.
~.~.8~
The present invention relates to fuel-water
seyarators for use in diesel engine applications to separate
wa-ter from diesel fuel. More particularly, the present
invention relates to separators which include a fuel flow
control valve responsive to the level of accumulated liquid
contaminants, including water) in the separator.
It is well known that diesel fuel often contains
rather substantial amounts of liquid contaminants,
particularly water, which, if not removed, will da~age the
fuel injection system of diesal engines. ~lany fuel-water
separators and filters have been suggested in the prior art,
so~e of which have included buoyantly operated valves for
sensing the level of liquid contaminants, including water,
which have been separated from the fuel and accumulated in
the fuel-water separator. Examples of such separators are to
be found in United States Patents 4,017,397; 3,931,011; 3,273,716;
3,187,895; and 2,170,247. Other fuel-water separators and
filters in the prior art have incorporated devices for
electrically indicating the level of contaminants, including
water, separated and accumulated by the separators and
filters. Examples of such devices are to be found in United
States Patents 4,010,101 and 3,012,675.
Despite the presence of buoyantly operated valves
for automatically draining contaminants from fuel-water
separators and the presence of electrical indicating means
for indicating critical levels of contaminants within
fuel-water separators, the failure or malfunction of such
features is not unknown, whereupon water which has been
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~3B;~29
separated from the fuel and accumulated by the separator is
allowed to pass from the separator to the engine, resulting
in serious engine damage. It is therefore an object of the
present invention to incorporate within a fuel-water
separator a control means for preventing serious engine
damage in the event that the fuel-water separator becomes
substantially filled with water despite the presence of
signalling or valving means normally operable in response to
such condition.
The present invention constitutes an improvement
over prior art fuel-water separators and the preferred
embodiment herein illustrated constitutes an improvement over
the separator disclosed in our earlier Canadian application
Serial No. 396,931, filed February 24, 19~2. A fuel-water
separator according to the present invention includes a con-
tainer having entry and exit ports for fuel and water-
separation means in the container between the entry and
exit ports for separating water from the fuel. Typically,
there is included means for draining the separated water from
the container and means for indicating when water is to be
drained. In accordance with the present invention, the
fuel-water separator also includes means for at least
partially closing the exit port in response to a
predetermined level of separated water in the container to
reduce fuel flow through the exit port to a predetermined
level whereby the reduction in fuel flow provides an
indication that the separated water needs to be drained.
Preferably, the predetermined level of reduced fuel flow is
such that the diesel engine is incapable of operati.on above
an idle level. This feature has the advantage of permitting
the restricted engine operation at a speed sufficient to
maintain engine-operated safety equipment such as power
s~eering~ power brakes, and the like, yet will deter any
long-term operation of the engine which might cause engine
damage.
In accordance with the present invention, a
fuel-water separator can include signal means for sensing a
predetermined level of separated water in the container. The
sensing means in turn can actuate an appropriate indicator
visually perceivable to the engine operator which indicates
the existence of an undesirably high level of separated
water in the fuel-water separator. Further, there is
provided a pair of passages leading to the outlet of the
fuel-water separator, one of which is much smaller than the
other, the smaller passage being of such a size as to
reduce fuel flow to permit only restricted operation of the
engine. There is further provided valve means actuable for
closing the larger of the passages leading to the outlet,
the valve means being actuable by a water level in the
fuel-water separator in excess of that necessary to actuate
the sensing means. This feature has the advantage of first
indicating to the engine operator that certain remedial
action is desirable. Thereafter, if normal engine operation
is continued for any substantial period of time, thereby
permitting further accumulation of water, the valve means
is actuated to close a first passage leading to the fuel
outlet of the separator. The valve means leaves open a
second smaller passage leading to the fuel outlet to reduce
fuel flow and to permit only restricted operation of said
engine.
2~
A fuel-water separator according to the present
invention can incorporate various other features to
advantageously separate and settle water from fuel in
accordance with our earlier application Serial No. 396,931,
and in accorclance with the prior art. Various other features
and aclvantages of the presen-t invention will become apparent
in view of the following detailed description of the embodi-
ment illustrated in the accompanying drawings which exemplify
the best mode of carrying out the invention as presently
perceived. In such drawings:
Figure 1 is a full sectional view of a separator
embodying the features of the present invention taken
generally along the axis of the container;
Figure 2 is a sectional view of a portion of the
separator of Figure 1 embodying a water level sensing probe;
Figure 3 is a sectional view of a portion of the
separator of Figure 1 showing the fuel flow reduction control
valve in a closed condition due to the high level of water
accumulated in the separator; and
Figure 4 is an elevation view partially in section of
an alternative embodiment of -the invention.
The fuel-water separator shown in Figures 1 - 4
includes a container 10, an entry port 12 to the container
10, and an exit port 1~ from the container 10. A plurality
of means 16 are provided in the container 10 between the
entry port 12 and the exit port 14 for separating water from
fuel passing through the separator. A drain 18 is provided
for draining the separated water from the fuel-water
separator. The container 10 is shown to comprise a
cylindrical housing 20 having an integral conical bottom 22
with the drain 18 situated at the central lowest portion of
the sloped bottom 22. A closure 24 is fixed to the top of
the cylindrical housing 20 to completely seal the container
10 except for the entry port 12, exit port 14, and drain 18.
The drain 18 is shown to include a threaded petcock
2~ which, by opening and closing, can control the drainage of
water from container 10. A buoyant ball 28 is provided
having a specific gravity such that it floats on water but
does not float on fuelO The fuel-water interface is
indicated in the Figsu by line I. Upon opening petcock 26,
the water is permitted to drain only down to a predetermined
level at which time ball 28 will descend and close drain
opening 18 whereupon petcock 76 can be closed.
Entry port 12 includes a tube 30 descending into a
-~ lower portion of the separator to a first water-separation
means 32. The first water separation means 32 comprises an
arcuate passageway 34 designed to apply a centrifugal force
to the fuel-water mixture passing therethrough. The
passageway 34 opens into chamber 36 defined by a lower porous
plate 38 and an upper member 40. The first water separation
means 32 is intended to centrifugally act on the fuel-water
mixture, thereby forcing the higher density water to the
outer wall so that the water is separated from the fuel and
drains downwardly, while the lighter densi~y fuel concentrates
at the upper member 40 passing through opening 42.
The fuel, now with a reduced amount of water
present, passes upward into chamber 44, the size of which is
much larger than chamber 36. Because of the larger size of
the chamber, the apparent rate of flow of fuel through
chamber 44 is much slower, thus permitting water to settle
from the fuel-water mixture by gravity, the water precipating
through aperture 46 to the water-collecting chamber 48. The
fuel, with yet an additional amount of water removed, passes
from chamber 44 into an inner chamber 50 within an outer cup
52. Within outer cup 52 there is provided a sleeve 54 of
untreated fiberglass or other appropriate media through which
the fuel is caused to pass. A surface tension separator 16
is provided arond the outer periphery of the sleeve 54 to
separate fine water particles from the fuel. The fine water
particles are caused to descend through conical chamber 56,
passing by buoyant ball 58 into drainage tube 60, leading to
the water-collection chamber 48. Ball 58 has a buoyancy
characteristic similar to that of ball 28, thereby permitting
the downward passage of water from chamber 56 to drain tube
60, but preventing the downward passage of fuel. Likewise,
should the level of the water within container 10 be high
enough, ball 58 rises to close opening 62 to prevent water
from moving upward through opening 62.
After the fuel has passed through the surface
tension separator 16 and the fiberglass media 54, it
proceeds through opening 64 in inner cup 66 to the final
separation means 68 which comprises a second surface tension
separator 16. The tension separators 16 are preferably
cylindrical elements of monofilament polyester fiber,
monofilament TEFLON, or other similarly effective
materials. The tension separators 16 operate by surface
tension to separate any remaining water from the Euel
which has proceeded through the various stages of the
fuel-water separator.
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29
A lower end 70 of the cylindrical separ~tion means
68 is closed by a closure holding a buoyant ball 72. Above
the buoyant ball 72 there is provided a pair of passages 74
and 76 leading to exit port 14. Passage 76 is of a much
smaller diameter than passage 74. Ball 72 has a buoyancy
characteristic similar to that of balls 28 and 58, thereby
normally permitting fuel to pass through the larger passage
74, but preventing fuel flow through passage 74 when the
level of water within the fuel flow through inner cup 66
rises to a predetermined level covering approximately
one-half (~) of surface area of the separator 16. At such
predetermined level, water begins to penetrate the separator
16 and settle to the bottom 70, thereby causing the ball 72
to rise. This relationship is shown in Fig. 3. Upon the
upward motion, the buoyant ball 72 seats against passage 74,
thereby closing passage 74 and leaving only passage 76
leading to exit port 14.
As shown in Fig. 2, there is provided a water
level sensor probe 80. The probe 80 may be any of a
number of commercially available liquid level probes
adapted to either capacitive or resistive circuitry to sense
the level of the water within container 10. The liquid
level probe 80 may conventionally be hooked to an indicator
light on the dashboard of a vehicle or to a solenoid valve
which would replace petcock 26. In the event that probe 80
was connected to an indicator light, the presence of water
at the predetermined level indicated in Fig. 2 would
normally cause the light to become illuminated, warning the
operator of the fact that the container 10 needs to be
drained.
In the event of an electrical failure, however, the
operator would not receive any signal or indication from the
liquid level probe 80 of the water level. With continued
operation, the level of watee within the fuel-water separator
would continue to rise within the container 10 until it
reaches a second higher predetermined level, as shown in
Fig. 3 whereupon buoyant ball 72 would seat against the
opening of passage 74l thereby closing the opening. Fuel
would then pass only through the much smaller opening 76~
Preferably, the size of opening 76 would be gauged so that
the fuel would flow at a rate sufficient only to allow
restricted operation of the engine supplied by the fuel. The
significantly reduced level of engine operation would then
indica~e to the engine operator that immediate remedial
action was required in order to prevent damage to the engine.
In a vehicle, for instance, the reduced flow rate might be
reduced to a predetermined minimum level required to operate
the engine at a speed sufficient to operate engine-operated
safety equipment such as power steering, power brakes, etc.
In other instances, the reduced flow rate might permit the
vehicle to move at slow speed to a maintenance area.
As shown in Fig. 4, the size of the
water-collecting chamber 48 can be increased in size by
providing a longer container side wall 20 and means 84 for
maintaining the various water-separation means 32, 68, etc.,
in an upper portion of the container 10. As illustrated, the
means 84 comprises a spring which also performs the function
of retaining ball 28 within operable range of the seat 86 of
drain 18. The spring 84 contacts the inside surface of
sloped bottom 22 and ridge 88 on a downward axial projection
8'~
90 of porous plate 38, thereby defining a cylindrical cage
within which ball ~8 is free to vertically move with the
interface between the fuel and separated water.
While the invention has been described with
reference to the presently preferred and illustrated
embodiment thereof, it is not intended that the invention be
unduly limited by this description of the preferred
embodiment, and instead, it is intended that the invention be
defined by the means and their obvious equivalents set forth
in the following claims.
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