Note: Descriptions are shown in the official language in which they were submitted.
CA 02755188 2011-10-18
FIREPLACE INSERT
TECHNICAL FIELD
[0001] This application is directed, in general, to a
fireplace and, more specifically, to a modulating flame gas
fireplace.
BACKGROUND
[0002] Even with the advent of central heat, many homes and
business still use fireplaces. In some instances, they are used
to produce additional heat for a given space, however, in other
applications, their presence is purely aesthetic. Many of the
advances in fireplace technology have primarily been in the
arena of providing fireplace systems that are designed to better
transfer the heat generated by the fire. This has particularly
been the case with the advent of natural gas fireplaces that are
much cleaner and more convenient than conventional wood-burning
fireplaces.
SUNIIMMARY
[0003] One aspect provides a fireplace insert comprising: a
gas burner, a fuel/air control valve coupled to the gas burner,
a blower coupled to the gas burner, and a controller coupled to
the fuel/air control valve and the blower; wherein the
controller controls at least one operational parameter of the
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fuel/air control valve and the blower to produce a flame pattern
generated by the gas burner.
[0004] A method of manufacturing a fireplace insert
comprising: providing a gas burner, coupling a fuel/air control
valve to said gas burner, coupling a blower to said gas burner,
and coupling a controller to said fuel/air control valve and
said blower wherein said controller controls at least one
operational parameter of said fuel/air control valve and said
blower to produce a flame pattern generated by said gas burner.
BRIEF DESCRIPTION
[0005] Reference is now made to the following descriptions
taken in conjunction with the accompanying drawings, in which:
[0006] FIG. 1 is a partial sectional view of one embodiment
of a fireplace insert constructed in accordance with the
principles of the present disclosure;
[0007] FIG. 2 is a sectional view of the burner and flame
pattern of FIG. 1;
[0008] FIG. 3 is a partial sectional view of an alternative
embodiment of the fireplace insert;
[0009] FIG. 4 is a partial sectional view of a second
alternative embodiment of the fireplace insert; and
[0010] FIG. 5 is a partial sectional view of a third
alternative embodiment of the fireplace insert.
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DETAILED DESCRIPTION
[0011] FIG. 1 illustrates a partial sectional view of one
embodiment of a fireplace insert 100 constructed in accordance
with the principles of the present disclosure. In this
embodiment, the fireplace insert 100 comprises: a gas burner
110, a fuel/air control valve 120, a blower 130, and a
controller 140. The gas burner 110 may be of any desired shape;
however, gas burners having a particular horizontal geometric
cross section 2A-2A, e.g., circular, rectangular, elliptical,
inverted cone, etc., have special application in that they
readily produce flame cross sections 2A'-2A' that reflect, or
are similar, to that of the burner horizontal geometric cross
section, i.e., circular, rectangular, elliptical, inverted cone,
etc., respectively. A gas burner 110 with a circular cross
section is illustrated in FIG. 2. Also, in one configuration,
the gas burner 110 may have a bowl-shaped vertical cross section
as can be seen in FIG. 1 and the flame pattern 150 has a similar
vertical cross section emanating from the top 111 of the gas
burner 110. Some of the geometric cross sections into which the
gas burner may be configured are illustrated and discussed
below. One who is of ordinary skill in the art will readily
conceive of other geometric cross sections applicable within the
principles of the present disclosure.
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[0012] In certain embodiments, the fuel/air control valve
120, the blower 130, and the controller 140 of the fireplace
insert 100 may be powered by conventional line voltage of 110-
115 VAC. However, in other embodiment, the fuel/air control
valve 120, the blower 130, and the controller 140 may be powered
by direct current. The blower 130 is pneumatically coupled to
the gas burner 110 through a duct 160, such as gas pipes, which
has the fuel/air control valve 120 interposed the blower 130 and
the gas burner 110. The controller 140 comprises a
microprocessor with a programmable memory for controlling at
least one operational parameter of the fuel/air control valve
120 and the blower 130. In one embodiment, the controller 140
may command a set program over a specified period of time and
then cyclically repeat the program. In another embodiment, the
controller 140 may be set to command a varying function. so as to
give the appearance of a traditional wood fireplace with varying
flame colors and heights. In an alternative embodiment, the
controller 140 may be replaceable as a complete unit or a plug-
in board, each different unit having a specific program
preprogrammed. Alternatively, the controller 140 may be
reprogrammed through a USB connection to a personal computer.
[0013] The operational parameters of the fuel/air control
valve 120 and the blower 130, in certain embodiments, may
include the following: fuel (natural gas or propane) velocity,
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air velocity, fuel/air ratio, and an equivalence ratio. The
fuel velocity may be controlled by setting the fuel/air control
valve 120 with the controller 140 sensing the line gas pressure
and adjusting the fuel/air control valve 120 appropriately. The
air velocity may be controlled by the rotation speed of the
blower 130 and the setting of the fuel/air control valve 120 by
the controller 140. The fuel/air ratio may be controlled by the
controller 140 when it sets the fuel/air control valve 120 for
the proper mix to obtain a desired fuel/air ratio. The
equivalence ratio cp is defined as: (F/A ratio)actual divided by
(F/A ratio) stoichiometric= One who is of skill in the art is
familiar with the meaning of a stoichiometric fuel/air ratio.
The equivalence ratio may be determined by the controller 140
for appropriate adjustment as necessary for a desired flame
pattern or color.
[0014] The operational parameters of the fuel/air control
valve 120 and the blower 130 can affect the flame pattern. For
example, if a constant fuel/air ratio is maintained, but the
volume of fuel and air is increased, the length of the flame
will increase. That is, height h of the flame pattern is a
direct function of the volume of fuel and air delivered to the
burner 110 by the blower 130. If the constant fuel/air ratio is
maintained, but the volume of fuel and air is decreased, the
length of the flame will also decrease. If the flow volume of
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fuel and air is increased by increasing fuel while holding the
air constant, then the flame will tend to be more yellow in
color. If the opposite is commanded, i.e., the flow volume of
fuel and air is increased by increasing air while holding the
fuel volume constant, then the flame will tend to be more toward
blue in color. These various operational parameters of the
fuel/air control valve 120 and the blower 130 are controlled by
the controller 140 adjusting the fuel/air mixture with the
fuel/air control valve 120 and the flow volume by increasing or
decreasing the rotational speed of the blower 130. By adjusting
one or more of the operational parameters, a very artistic flame
having different heights, colors, or both over a programmed
period of time may be easily achieved. The time may be varied
in such a way so to create a constant changing flame or produce
repeated patterns over a set period of time, much in the same
way as a water fountain might be operated.
[0015] FIG. 2 illustrates a sectional view of the burner 110
and flame pattern of FIG. 1. As can be seen, the flame pattern
reflects the burner shape.
[0016] FIG. 3 illustrates another embodiment of a fireplace
insert 300. In this particular embodiment, the fireplace insert
300 comprises: a multiple gas burner 310, a fuel/air control
valve 320, a blower 330, and a controller 340. The number of
gas burners 310 may vary depending on the desired design. FIG.
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3 illustrates one such design that is configured as a dual gas
burner. The illustrated dual gas burner 310 has two concentric
bowl-shaped burners 311, 312. The fuel/air control valve 320,
blower 330, and controller 340 combine to produce two concentric
flame patterns 351, 352 from the two concentric bowl-shaped
burners 311, 312. In this configuration, the flame patterns of
the individual burners 311, 312 will be substantially parallel
to each other because the individual burners 311, 312 are fed
and controlled by the same fuel/air control valve 320, blower
330, and controller 340. However, one flame pattern hl, h2 may
be longer or shorter than the other by controlling the fuel/air
entrance orifices 313, 314 of each burner 311, 312,
respectively.
[0017] As with previous embodiments, the operational
parameters of the fuel/air control valve 320 and the blower 330
can be varied to affect the flame pattern and be operated and
controlled by way of the controller 340 in the manner described
above, such that by adjusting one or more of the operational
parameters, a very artistic flame having different heights,
colors, or both over a programmed period of time may be easily
achieved. The time may be varied in such a way so to create a
constant changing flame or produce repeated patterns over a set
period of time, much in the same way as a water fountain might
be operated.
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[0018] FIG. 4 illustrates a partial sectional view of a
second alternative embodiment of a fireplace insert 400. The
fireplace insert 400 comprises: first, second, and third gas
burners 411, 412, 413, a fuel/air control valve 420, a blower
430, and a controller 440. All three gas burners 411, 412, 413
are fed from the same fuel/air control valve 420, blower 430,
and controller 440. In this configuration, the first and second
gas burners 411, 412 are inverted cone-shaped. The first and
second gas burners 411, 412 produce inverted, truncated cone-
shaped flame patterns 415, 416, respectively, that may be varied
in color by adjusting the flow velocity for each burner 411,
412. For the first and second burners 411, 412, this is
achieved by selection of the size of the aperture 419 in a split
disk 414 surrounding a central tube 417 that feeds the third
burner 413. The third gas burner 413 may be designed to produce
a conventional single flame that is more yellow in color. This
color is achieved by controlling the aperture size of a flared
end 418 of the central tube 415. Flame heights of the burners
411, 412, 413 and the overall flame patter may be controlled as
detailed above with respect to other embodiments.
[0019] FIG. 5 illustrates a partial sectional view of a third
alternative embodiment of the fireplace insert 500. In this
particular embodiment, the fireplace insert 500 comprises: first
through fifth gas burners 511--515, first and second fuel/air
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control valves 521, 522, first and second blowers 531, 532, and
first and second controllers 541, 542. Though the design may
vary, the illustrated embodiment shows the first and second gas
burners 511, 512 configured as two concentric bowl-shaped
burners 511, 512. The third, fourth, and fifth gas burners 513,
514, 515 may be conventional single flame burners. The first
and second gas burners 511, 512 are served by the first fuel/air
control valve 521, the first blower 531, and first controller
541. The third, fourth and fifth gas burners 513, 514, 515 are
served by the second fuel/air control valve 522, the second
blower 532, and the second controller 542. Each of the first
and second controllers 541, 542 may have different programs to
enhance contrast between the two types of burners, i.e., the
first and second gas burners 511, 512 vs. the third, fourth and
fifth gas burners 513, 514, 515. Flame height and color of each
set of burners are controlled as detailed above.
[0020] Thus, a fireplace insert has been described that
controls not only the height of the flame pattern emanating from
multiple burners, but also, the shape and color of the flames.
[0021] For the purposes of this discussion, use of the terms
"providing" and "forming" includes: manufacture, subcontracting,
purchase, etc. Those skilled in the art to which this
application relates will appreciate that other and further
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additions, deletions, substitutions and modifications may be
made to the described embodiments.
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