Note: Descriptions are shown in the official language in which they were submitted.
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FUEL EQUALIZATION SYSTEM
FIELD OF INVENTION
[0002] The present invention relates, in general, to a fuel equalization
system,
and deals more particularly with a fuel equalization system that is capable of
maintaining proper air/fuel mixtures even during times of decreased or blocked
air flow.
BACKGROUND OF THE INVENTION
[0003] Burners are utilized in many integrated systems, such as in boilers,
furnaces and water heater applications. These burners are typically fed an
enriched air stream containing a predetermined concentration of fuel mixed
therein. Of great importance, therefore, is the ability of the system to
maintain a
proper air/fuel mixture during operation of the system.
[0004] Typically, a filter box includes one or more orifices to accept
incoming
air and fuel streams. A blower is operatively connected to the filter box, and
propels the air/fuel mixture from the filter box, to an integrated Iburner.
Any
blockage of the incoming air or fuel streams, or of the flue leading to the
burner,
will cause a change in the air/fuel mixture being fed to the burner, with a
corresponding potential for the harmful buildup of CO.
[0005] Known systems oftentimes employ one or more sensors within the filter
box coupled with a variable speed blower to regulate the introduction of the
air/fuel mixture to the burner. While these systems operate reasonably well
during normal times, they suffer under blocked-flue or blocked-air inlet
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conditions due to the swirling air currents created by these adverse
conditions.
That is, known systems arrange the air/fuel inlet orifice(s) adjacent to, or
near,
the blower inlet, therefore the turbulence created at the air in.let by a
blocl:age
creates an 'implicd' flow in and around the sensors. Thus, during times of
blockages, the sensors of known systems are incapable of accurately
controlling
the desired air/fuel mixture, due to the swirling and turbulent implied flows
wrashing over the sensors.
to, Known systems are therefore unable to accurately contro] the air/ fuel
mixture during times when the air inlet, or flue, is partially or coinpletely
blocked.
[0007) With the forgoing problems and concerns in mind, itis the general
object
of the present invention to provide a fuel equalization system that can
accurately
detect and respond to situations of air blockage so as to maintain safe
air/fuel
mixtures.
SU14iMARY OF THE INVENTION
ronoeJ It is one object of the present invention is to provide a fuel
equalization
svstem_
(ix,ogi It is another object of the present invention is to provide a fuel
equalizatio system which is capable of maintaining a desired air/fuel ratio.
toooioi It is another object of the present invention is to provide a fuel
equalization system which is capable of maintaining a desired air/fuel ratio
even during times of blocked a)'r flow.
(oooiil It is another object of the present invention is to provide a fue]
equalization system which reduces the turbulence of a blocked air flow.
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[00012] A further object of the invention is to position the air and fuel
inlet
orifices some distance from the blower inlet, thereby isolating the air and
fuel
inlet orifices from excessive turbulence caused by any blockages.
[00013] A further object of the invention is to decrease the number of clips
that
are engaged about the respective connected adjacent flange portions to prevent
leakage.
[00014] A further object of the invention is to provide a fuel equalization
system
which substantially eliminates the creation of harmful gas build-up cluring
times
of partially or completely blocked air flows.
[00015] In accordance, therefore, with one embodiment, it is an object of the
present invention to provide a fuel equalization system includes a filter box
for
accepting an air stream and a fuel stream, the air stream and the fuel stream
mixing to form a mixed air/fuel stream. A blower is provided that has an inlet
for
accepting the mixed air/fuel stream from the filter box. An air deflection
member
is positioned in the path of the mixed air/fuel stream, between the filter box
and
the inlet, so as to reduce the turbulence of the mixed air/fuel stream.
In accordance with another aspect, the present invention provides a method of
reducing turbulence within a mixed air/fuel stream being provided to a blower,
the method comprising the steps of:
arranging a filter box to be in fluid communication with the blower;
providing the filter box with the mixed air/fuel stream;
channelling the mixed air/fuel stream along a path from the filter box to
the blower;
arranging an inlet opening in the blower to accept the miixed air/fuel
stream; and
positioning an air deflection means in the path so as to retard the
velocity and swirling nature of the mixed air/fuel stream.
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[00016] These and other objectives of the present invention, and thieir
preferred
embodiments, shall become clear by consideration of the specification, claims
and drawings taken as a whole.
BRIEF DESCRIPTION OF THE DRAWINGS
[00017] Figure 1 illustrates an exploded view of a fuel equalization system
according to one embodiment of the present invention.
[00018] Figure 2 is a partially exploded view of the fuel equalization system
of
Figure 1, in isolation.
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(oooi9i Figure 3 illustrates a schematic side view of a fuel equalization
system
according to another embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[000:01 Figure 1 illustrates an exploded view of a fuel equalization systein
10,
according to one ernbodim-ent of the present invention. As shown in Figure 1,
the fuel equalization system 10 includes a filter box 12 and a blower 14. An
air/fuel stream is directed by the blower 14 to a burner assembly 16, which in
tum is operatively connected to a boiler apparatus 15.
;ononi It will be readily appreciated that while the boiler apparatus 1S has
been
described in connection with Figure 1, the present invention is not so limited
in
this regard as the blower 14 may be connected to any suitable apparatus
without
departing from the broader aspects of the present invention.
[ooo:z) Figure 2 illustrates the fuel equalization system in isolation. As
shown in
Figure 2, the filter box 12 defines an inner box 20 having an air orifice and
fuel
entry 22. A duct section 24 is oriented between the filter box 12 and the
blower
14. An air stream and a fuel stream arc directed through the air orifice and
fuel
entry 22 via known means, and this mixture is then sucked through the duct
section 24 by the blower 14, past an un-illustrated flue and into the burner
assembly 16.
[ooov It is an important aspect of the present invention that the air orifice
and
fuel entry 22 is not positioned adjacent to the blower inlet 26, as is
typically
known in the art. Instead, the present invention arranges the air orifice and
fuel
entry 22 as far away as possible from the blower inlet 26, thereby isolating
the
air orifice and fuel entry 22, and any associated sensors, from the turbulence
that
may be caused by any air/ fuel stream blockage.
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too024i Returning to Figure 2, a static impeller 28 is arranged within the
duct
section 24 and adjacent the blower inlet 26. As shown, the impeller 28 enjoys
a
diameter that is slightly less then the diameter of the enclosing spool piece.
When the oudet 30 of the blower 14 is partially or completely blocked, the
resultant swirling air/fuel stream 'backs up' and is redirected back through
the
duct section 24 and through the impeller 28. The vanes 32 of the impeller 28
effecbvely reduce or elin,inate the velocity and rotation of the redirected
air/ fuel sLreann passing there through.
[ooozi The velocity and rotation of the re-directed air/fuel stream is further
reduced or eliminated by the inclusion of a straightening blade 34, also
formed
in the duct section 24. As shown in Figure 2, the straightening blade 34 is a
generally flat piece of metal or plastic, and is preferably arranged along a
diameter of the duct section 24. 'fhe straightening blade 34 acts as a baffle
to
intercept and further restrai.n the swirling air/fuel stream, prior to the
redirected
air/fuel stream entering the filter box 12.
tooozo It is therefore another important aspect of the present invention that
the
static impeller 28 and the straightening blade 34 effectively reduce or
eliminate
any implied air flow into the filter box. 'l'hat is, the static impeller 28
and the
straightening blade 34 reduce the velocity and swirling nature of the air/fuel
stream that is redirected back through the duct section 24. When coupled with
positioning of the air orifice and fuel entry 22 a distance away from the
blower
inlet 26, the static impeller 28 and the straightening blade 34 effectively
isolate
the air orifice and fuel entry 22 from the implied air flow that is generated
by the
blockage of the blower outlet 30. Thus, any sensors mounted adjacent the air
orifice and fuel entry 22 do not suffer from imprecise readings, and the fuel
equalization system 10 can therefore be operated even in conditions of nearly
complete blockage of the blower outlet 30, or the like.
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1000271 While the straightening blade 34 in Figures 1 and 2 is shown as being
oriented substantially vertically, and extending substantially the entire
diameter
of the cluct section 24, the present invention is not limited in this regard.
Indeed,
the straightening blade 34 need not extend vertically, or across the entire
diameter of the duct section 24, nor does the straightening blade 34 need to
extend preciseiy along a diameter of the duct section 24, in order to
substantially
reduce or elinii ate the velocity and swirling nature of the redirected, or
implicd, air/fuel strea~=n.
[ooo2e) The embodiment shown and described in connection with Figures 1 and 2
has depicted a centrifugal blower 14, hourever the present invention is not
limited in this regard. Figure 3 illustrates a schematic side view of a fuel
equalization system 50 according to another embodiment of the present
invention. As shown in Figure 3, the fuel equalization system 50 includes a
squirrel cage blower 52 operably connected to a filter box 54. An air orifice
and
fuel entry 56 is formed in the filter box 54 and provides the fuel
equalization
system 50 with the required air/fuel stream in aivell known manner.
fooox9l Also shown in Figure 3 is a squirrel cage impeller 58 which is
specially
equipped with an air deflector plate 60. The deflector plate 60 is preferably
arranged tvithin the throat of the impeller 58 and is shaped to capture the
majority of the redirected air/fuel flow, created by a blockage of the
unillustrated blower outlet, or the like, back into the blower 52. In this
manner,
any swirling, high velocity and redirected air/fuel stream created by a
blockage
of the blower outlet is largely kept within the blower 52, and consequently
does
not adversely affect the air orifice and fuel entry 56, or any related sensors
disposed within the filter box 54.
(000301 The embodiment shown in Figure 3 also arranges the air orifice and
fuel
entry 56 as far away from the blower inlet 62 as possible, similar to the
embodiment of Figures 1 and 2, so as to further isolate the air orifice and
fuel
entry 56 from the effects of any implied air flow.
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(00o311 A straightening blade, or baffle, 64 is located in the filter box 54
in much
the same manner that the straightening blade 34 is arranged in the embodiments
of Figures 1 and 2. That is, the straightening blade 64 is located so as to
substantially bisect the incoming redirected air/ fuel stream, thereby
reducing its
velocity and swirling nature.
iooo.x2) Although the embodiments of Figures 1-3 have illustrated the present
invention as it is implemented in connection with a centrifugal blower system,
and a squirrel cage blower system, the present invention is not so limited in
this
regard. Indeed, regardless of the type of blower that is employed, or the
nature
of the apparatus to which the blower provides the air/ fuel mixture, the
present
invention envisions disposing a straightening blade/baffle within the path of
any redirected air/ fuel stream. The baffle itself may have a nuniber of
possible
configurations and dimensions, provided that it extends outwardly into the
path
of any redirected air/fuel stream so as to reduce the velocity of the
redirected
air/ fuel stream, as well as reducing the swirling nature of the redirected
airlfuel
stream.
(ooo3,1 'Ihe use of the static impeller 28, or the air deflector plate 60, in
combination with locating the air orifice and fuel entry 56 as far as possible
from
the blower inlet 26/62, also assists in reducing the velocity of the
redirected
air/fuel stream, as well as reduang the swirling nature of the redirected
air/fuel
stream.
1000341 Thus, the present invention substantially eliminates the erroneous
sensor
readings and possible CO contamination stemming from a blocked blower
outlet, or the like. By removing the effects of the implied air rlow from the
present fuel equalization system, the present invention is capable of properly
regulating the air/fuel mixture that is provided to a blower and burner
assembly, up to and including properly regulating the air/fuel mixture even
during times of near complete blockage of the blower outlet or burner flue.
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rooo,5) While the invention has been described with reference to the preferred
embodiments, it will be understood by those skilled in the art that various
obvious changes may be made, and equivalents may be substituted for elements
thereof, without departing from the essential scope of the present invention.
Therefore, it is intended that the invention not be limited to the particular
embodiments disclosed, but that the invention includes all embodiments falling
within the scope of the appended daims.
