Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
CA 02870899 2016-06-14
DOUBLE VENTURI BURNER
TECHNICAL FIELD
The present disclosure relates to a burner with a double inlet.
BACKGROUND
Burners generally include a single inlet coupled to a single burner head
proximate an
outlet. For example, a flammable fluid, as natural gas may be fed into the
inlet of the
burner and combusted proximate the burner head.
SUMMARY
In various implementations, a burner may include a double inlet, such as two
venturi
inlets. Fuel may be supplied to the burner via two opposing inlets. The fuel
may mix
with air in the burner and at least partially combust proximate the burner
heads.
In various implementations, a burner may include a body, a plurality of burner
heads
individually coupled to the body, and two venturi inlets coupled to the body.
The body
may include a first arm, a second arm and a burner region coupled to the arms
and
configured to receive an air stream and a fuel stream from the arms. The
venturi inlets
may include a first venturi inlet coupled to the first arm of the body and a
second venturi
inlet coupled to the second arm of the body. The first venturi inlet and the
second
venturi inlet may be opposingly disposed.
Implementations may include one or more of the following features. The first
arm may
be disposed proximate a first end of the body, and the second arm may be
disposed
proximate a second end of the body. The body may include a first mixing length
and a
second mixing length. The first mixing length may include the distance between
a first
end of the first arm and a second end of the first arm. The second mixing
length may
include the distance between a first end of the second arm and a second end of
the
second arm. The first venturi inlet may be coupled proximate a first end of
the first arm,
and the second venturi inlet may be coupled proximate a second end of the
second arm.
The plurality of burner heads may include a first burner head and a second
burner head.
The first burner head may have a first height and the second burner head may
have a
second height. The second height may be greater than the first height, in some
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implementations. The plurality of burner heads may include at least two burner
heads
comprising approximately similar heights. The two venturi inlets may be
adapted such
that a fuel stream from a fuel inlet may be provided to the two venturi
inlets. The velocity
of the fuel stream may generate a primary air stream from the air proximate
the two
venturi inlets, and the primary air stream may be provided to the two venturi
inlets.
In various implementations, an assembly may include a burner. The burner may
include
two venturi inlets adapted to receive a fuel stream and a primary air stream.
The burner
may include a body with a burner region configured to receive the fuel stream
and the
primary air stream from the two venturi inlets and one or more burner heads
individually
coupled to the burner region.
Implementations may include one or more of the following features. The
assembly may
include a fuel inlet. The fuel inlet may provide the fuel stream to the two
venturi inlets of
the burner. The fuel inlet may include at least one outlet proximate each
venturi inlet of
the burner. Each outlet of the fuel inlet may be adapted to provide at least a
portion of
the fuel stream to the venturi inlet of the burner proximate each outlet. In
some
implementations, each outlet of the fuel inlet may include an outlet cross-
sectional area
that is less than an inlet cross-sectional area of a proximate venturi inlet.
The burner
may include more than one burner head. At least two of the burner heads may
have
similar heights. In some implementations, at least two of the burner heads may
have at
least two different heights.
In various implementations, generating heat may include allowing at least a
portion of a
fuel stream to flow from at least one outlet of a fuel inlet to two venturi
inlets of a burner.
The two venturi inlets may be opposingly disposed. A primary air stream may be
allowed to flow at least partially into the two venturi inlets of the burner.
At least a
portion of the primary air stream and at least a portion of the fuel stream
may be allowed
to mix in a body of the burner, and the body may comprise a burner region
configured to
receive the fuel stream and the primary air stream from the two venturi
inlets. The mixed
stream, which may include at least a portion of the primary air stream and at
least a
portion of the fuel stream, may be allowed to flow to the burner heads of the
burner.
Combustion of the mixed stream proximate the burner heads of the burner may be
allowed. The burner heads may be individually coupled to the burner.
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Implementations may include one or more of the following features. A secondary
air
stream from the air proximate the burner heads may be allowed to mix with the
mixed
stream proximate the burner heads. The primary air stream may have a greater
flow
rate than the secondary air stream. The velocity of the fuel stream from at
least one of
the outlets of the fuel inlet may increase the velocity of the primary air
stream into the
two venturi inlets. Allowing at least a portion of the primary air stream and
at least a
portion of the fuel stream to mix may include allowing at least a portion of
the primary air
stream and at least a portion of the fuel stream to mix along a mixing length
of a body of
the burner. Allowing combustion of the mixed stream may include generating a
flame
proximate each burner head of a burner. Allowing combustion of the mixed
stream may
include allowing at least partial combustion of the fuel of the fuel stream.
The details of one or more implementations are set forth in the accompanying
drawings
and the description below. Other
features, objects, and advantages of the
implementations will be apparent from the description and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of this disclosure and its features,
reference is now
made to the following description, taken in conjunction with the accompanying
drawings,
in which:
Figure 1A illustrates an implementation of an example burner.
Figure 1B illustrates an implementation of an example burner during use.
Figure 2 illustrates an implementation of an example process for providing
heat using a
double venturi burner.
Figure 3 illustrates an implementation of an example process for providing
heat using a
double venturi burner.
Like reference symbols in the various drawings indicate like elements.
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DETAILED DESCRIPTION
Burners may allow combustion of fuel in the presence of air. Fuel may include
flammable fluids, such as natural gas, heating oil, and/or propane. A burner
may be
utilized to provide heat, for example, in heat exchangers, such as furnaces;
boilers;
and/or other applications.
In various implementations, a burner with two venturi inlets may be utilized.
The burner
may allow the flame profile of the flames generated by the burner to be
controlled. For
example, better mixing (e.g., more uniform) of air and fuel (e.g., when
compared with a
single inlet) may be allowed with a double inlet since air may contact more
external
surface area of the gas stream than when a similar amount of fuel is provided
through a
single inlet. In some implementations, a smaller footprint burner may be
utilized with a
double inlet since a comparable inlet to provide the same amount of gas and
air to an
inlet may utilize a larger single inlet. A smaller footprint may decrease
costs and/or
increase user satisfaction (e.g., by allowing smaller footprint applications,
such as
furnaces).
Figure 1A illustrates an implementation of an example double venturi inlet
burner 100.
The burner 100 may include a body 105 coupled to two inlets 110, 115, such as
venturi
inlets. The body may include a heat resistant material (e.g., metal and/or
other heat
resistant materials in the operating range of the burner). The burner may have
dimensions, such as length, width, and height, which may allow coupling and/or
disposition of the burner proximate a user (e.g., openings in a heat exchanger
through
which heat may be provided to the heat exchanger). The burner may have any
appropriate regular and/or irregular shape.
The body 105 of the burner 100 may include two arms, a first arm 120 and a
second arm
125. The first arm 120 may be coupled proximate a first end 130 of the body
105 and/or
the second arm 125 may be coupled proximate a second end 135 of the body. The
arms 120, 125 may be elongated members of the body 105.
The first arm 120 may be coupled at a first end 140 to the burner region 145
of the body
105 and coupled at a second end 150 to the first venturi inlet 110. The second
arm 125
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may be coupled at a first end 155 to the burner region 145 of the body 105 and
coupled
at a second end 160 to the second venturi inlet 115.
The arms may have a length and a cross-sectional area. For example, the first
arm 120
may have a length, which includes the sum of the first length 121 and the
second length
122. As illustrated, second arm 120 may have a length, which includes the sum
of the
third length 126 and the fourth length 127. The cross-sectional area of the
arm may be
less than a cross-sectional area of the inlet of the venturi inlets 110, 115.
The cross-
sectional area and/or shape of an arm proximate a second end may be
approximately
similar to the cross-sectional area and/or shape of the outlet of the venturi
inlets. The
arms 120, 125 may have any appropriate regular and/or irregular shape.
The body 105 may include a burner region 145. The burner region may be
disposed
between a first end 140 of the first arm 120 and the first end 155 of the
second arm 125.
The burner region 145 may include one or more burner heads. As illustrated,
the burner
region 145 includes a plurality of burner heads. The burner heads 170 may
include one
or more characteristics, such as width 175, a length (not shown), a distance
180
between burner heads (e.g., a perpendicular distance between an outer surface
of a first
burner head and an adjacent outer surface of an adjacent burner head), and/or
a height
185 (e.g., a distance above the outer surface of the body that a burner head
resides).
One or more of the characteristics may affect the flame profile (e.g.,
temperature, size,
and/or height of flame(s)) generated by burner head(s) (e.g., since the
characteristic(s)
may affect a fuel/air ratio and/or the clearance(s) between burner head(s) and
a device,
such as a heat exchanger).
In some implementations, the burner heads 170 may be coupled to the body at a
height
185 that is fixed. The burner head(s) 170 may be welded or otherwise affixed
to the
body at a height 185, in some implementations. In some implementations, the
burner
heads 170 may include a coupling member and the body may include a coupling
member adapted to engage with the coupling member of the burner head 170. For
example, at least a portion of an outer surface of a burner head may include
threads and
at least a portion of an inner surface of an opening in the body may include
threads
adapted to receive the threads of the burner head. In some implementations, at
least a
portion of the inner surface of the burner head may include threads adapted to
engage
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with threads on at least a portion of the body. Coupling the burner head and
the body of
the multi-burner head assembly may allow the burner head to be disposed at a
fixed
predetermined height.
The burner heads may be any appropriate burner head. For example, the burner
heads
170 may include openings formed in the body. The burner heads may include
cylindrical
protrusions extending from the body of the burner. The
burner heads maybe
approximately uniform in size and/or shape. In some implementations, more than
one
characteristic (e.g., height, width, length, clearance, and/or distance
between burner
heads) of two or more burner heads may be similar or different. For example,
the
burners may include adjustable height burner heads. In some implementations,
the
burner may include one or more burner heads at a similar height, such as first
burner
171 and second burner 172. The burner may include one or more burner heads at
different heights, such as first burner 171 and third burner 173. As
illustrated, a third
burner 173 may have a height greater than a height of a first burner 171
and/or a second
burner 172. Other burner heads may be utilized, as appropriate. U.S. Patent
Application
No. 14/079,826 entited "Multi-Burner Head Assembly", filed on November 14,
2013
(Attorney File No. P130022/1655.1700) describes various burner heads that may
be
utilized with the double venturi inlet burner.
In various implementations, the inlets of the burner may include a first
venturi inlet 110
and a second venturi inlet 115. The venturi inlets 110, 115 and the body 105
may be
coupled (e.g., fastened, affixed and/or welded). For example, the first
venturi inlet 110
and the second venturi inlet 115 may be may be welded to the body 105 (e.g.,
the first
venturi inlet 110 may be welded proximate the second end 150 of the first arm
110
and/or the second venturi inlet may be welded proximate the second end 160 of
the
second arm 115).
As illustrated, the first venturi inlet 110 and the second venturi inlet 115
may be disposed
opposingly. The two venturi inlets 110, 115 may be opposing such that a single
fuel inlet
190 may provide the fuel to both of the venturi inlets. For example, the fuel
inlet 190 may
include at least two outlets, a first outlet 191 and a second outlet 192. The
first outlet
191 may supply fuel to the first venturi inlet 110 and the second outlet 192
may supply
fuel to the second venturi inlet 115. The outlets 191, 192 of the fuel inlet
190 may have
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a cross-sectional area that is smaller than the cross-sectional area of the
inlet of the
venturi inlets 110, 115. Thus, fuel loss to the air surrounding the burner may
be
minimized.
The venturi inlets 110, 115 may have a size that includes a cross-sectional
area and a
length. The shape of the cross-section may be any appropriate shape. In some
implementations, the size and/or shape of the venturi inlet 110, 115 may be
based at
least partially on the use of the burner 100.
The venturi inlets 110, 115 may be utilized to provide fuel (e.g., natural
gas) and/or air to
the burner heads of the burner. The first venturi inlet 110 and the second
venturi inlet
115 may provide fuel and/or air to a plurality of burner heads. A burner may
include
more burner heads than venturi inlets, in some implementations. Thus, as
illustrated,
each venturi inlet (e.g., independently or in combination with another venturi
inlet)
provides fuel and/or air to more than one burner head.
The body 105 of the burner may have a first mixing length and a second mixing
length.
The first mixing length may be the distance the fuel entering the first
venturi inlet may
travel prior to combustion proximate a burner head of the burner. The second
mixing
length may be the distance the fuel entering the second venturi inlet may
travel prior to
combustion proximate a burner head. The first mixing length may be similar
and/or
different from the second mixing length. As illustrated, the first mixing
length may
include the length of the first arm (e.g., sum of 121 and 122) and the second
mixing
length may include the length of the second arm (e.g., sum of 126 and 127).
The first
mixing length and/or the second mixing length may be selected based on mixing
length
models.
In some implementations, the body 105 of the burner may have a configuration
such that
a cavity resides between the venturi inlets 110, 115 and the burner region 145
of the
body. The cavity may supply air to the venturi inlets (e.g., for mixing with
the fuel for
combustion). The size of the cavity may affect the amount of air (e.g.,
primary air
stream) that is allowed to flow into the venturi inlets 110, 115, in some
implementations.
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Although Figure 1A illustrates an implementation of a burner 100 and its
components,
other implementations may be utilized as appropriate. For example, the burner
heads
may include openings in the body through which fuel is provided. The arms may
radiate
from the body in a curved path. The burner may include one burner head. The
burner
may be a multi-burner head assembly, similar to the multi-burner head assembly
described in U.S. Patent Application No. 14/079,826 and include two opposing
venturi
inlets rather than a single venturi inlet. The burner heads may be uniform in
size and/or
shape. In some implementations, two or more fuel inlets may be utilized. In
some
implementations, the burner may not include a manifold. Utilizing a burner
without a
manifold may reduce costs associated with manufacture of the burner. In
some
implementations, high deep drawing parts may not be utilized with the burner.
By
utilizing one or more parts other than high deep drawing parts, costs may be
reduced. In
some implementations, the venturi inlet(s) may be formed with the body (e.g.,
a unibody
construction).
The burner 100 may be utilized in a variety of applications, such as furnaces
and/or
boilers. Figure 1B illustrates an implementation of a portion 101 of a furnace
assembly
that includes the burner 100, illustrated in Figure 1A, during use. As
illustrated, the
burner 100 generates flames 195 proximate the burner heads 170 of the burner.
The
burner may be designed such that flames may be inhibited from entering the
burner
head or otherwise causing flashback. For example, the burner head size and/or
shape,
burner mixing length, and/or inclusion of a flame arrestor may inhibit flames
195 from
entering the burner. The flames 195 generate heat. The heat may be provided to
an
assembly, such as a heat exchanger 197. The heat exchanger 197 may be a tube
and
shell heat exchanger, in some implementations, in which the heat from the
flames raises
the temperature of air, water, and/or refrigerant passing through the heat
exchanger.
The heat exchanger 197 may include openings 198. The burner may be disposed
proximate the heat exchanger 197 such that the openings 198 are at least
partially
aligned with the burner heads 170, and thus the flames proximate the burner
heads.
The burner head configuration (e.g., size, distance between burners, and/or
shape) may
be selected to minimize misalignment, and thus, heat loss, between the burner
100 and
the heat exchanger 197. A clearance 199 may exist between the heat exchanger
(e.g.,
an outer surface of the heat exchanger) and the burner (e.g., top surface 106
of the body
105, top surface 171 of a burner head 170).
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Although a heat exchanger in a furnace has been described in Figure 1B, the
burner
may be utilized in other applications, such as other types of boilers. A
clearance may
exist between an opening of the device of the application, such as a boiler,
and a burner
head. In addition, although a specific burner has been illustrated in Figure
1B, other
burners with two venturi inlets may be utilized.
During use, fuel (e.g., natural gas) may be provided to the burner via fuel
inlet. The fuel
may mix with a primary air stream (e.g., air proximate the venturi inlets)
along a mixing
length of the body. The mixed stream (e.g., fuel and air) may be provided to
the burner
head and at least partially combusted proximate the burner heads. The flame
generated
by the combustion may be inhibited from entering the burner head and/or body
of the
burner (e.g., by the velocity of the mixed stream, the burner head
characteristics, the
mixing length, and/or inclusion of a flame arrestor). The mixed stream may mix
with an
additional secondary air stream (e.g., air proximate the burner heads,
exterior to the
body) to further promote combustion.
Figure 2 illustrates an implementation of an example process 200 for use of a
burner. A
fuel stream may be provided to two venturi inlets of a burner (operation 210).
For
example, a fuel stream may be released at a first velocity from a fuel inlet
proximate the
venturi inlet(s). In some implementations, the velocity of the fuel stream may
direct the
fuel stream leaving the outlet(s) of the fuel inlet(s) towards the inlet(s) of
the venturi
inlet(s). The gas may be natural gas, in some implementations.
The fuel stream may be allowed to mix with air in the body of the burner
(operation 220).
An air stream may be provided to the body. The air stream may mix with the
fuel stream
in the body (e.g., in the arms, in the burner region, and/or other parts of
the body). The
properties (e.g., ratio of air/fuel, homogeneity of the mixture, and/or
velocity) of the
mixed stream may be at least partially based on the mixing length. For
example, if the
mixing length of the body is too short, portions of the mixed stream may
contain less air
than other potions.
At least a portion of the fuel stream proximate the burner head(s) may be
allowed to
combust (operation 230). For example, a flame from the combustion of the fuel
in the
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presence of air may be generated proximate the burner head. The flame may
reside
between the burner head the openings in a heat exchanger, in some
implementations
(e.g., in the clearance).
Process 200 may be implemented by various systems, such as system 100. In
addition,
various operations may be added, deleted, and/or modified. For example, a
secondary
air stream may be provided. The secondary air stream may be proximate the
burner
heads and/or may assist in the combustion of the fuel. The ratio of fuel/air
may affect
the flame produced by a burner during combustion. The flame profile (e.g., the
properties of the flame, such as temperature and/or size) may be determined
based on
characteristics of the burner head(s), in some implementations. For example,
since air
is mixed with fuel at the burner head (e.g., secondary air stream), the
fuel/air ratio and/or
the amount of secondary air stream that is allowed to mix with the fuel may be
affected
by characteristics of the burner head such as clearance, height, length,
shape, and/or
width. For example, a slit or rectangular shaped (e.g., cross-sectional shape)
burner
head may allow a greater amount of air to be mixed with the fuel at the burner
head than
a circular shaped (e.g., cross-sectional shape) burner head. A burner head
with a first
height may mix with less air than a second burner head with a second height
that is less
than the first height. In some implementations, the distance between burner
heads may
affect the flame profile since when there is less spacing between burner heads
less air
may be allowed to mix with fuel at a burner head.
In some implementations, the flame produced by each burner head of each burner
may
receive different amounts of air proximate the burner heads, which may affect
the
temperature, size, and/or shape of the flames produced. Thus, some flames may
be the
result of fuel/air ratios that are too high or too low. This may cause
performance issues
(e.g., incomplete burn and/or increased operation costs) and/or increase the
risk for
flashback. By managing the fuel/air ratio (e.g., by managing the primary air
stream,
secondary air stream, mixing length, burner head properties, etc.), flashback
may be
minimized. For example, incomplete burn issues and/or partial combustion may
be
minimized by using the double venturi inlet burner since the amount of primary
air
stream supplied to the fuel stream may be increased (e.g., when compared with
a single
venturi burner design).
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Figure 3 illustrates an implementation of an example process 300 for using a
burner. At
least a portion of a fuel stream may be allowed to flow into two venturi
inlets of a burner
(operation 310). For example, a fuel inlet may include two outlets. Fuel may
flow from
an outlet of the fuel inlet to a venturi inlet such that at least a portion of
the fuel from the
fuel inlet may be provided to the burner for combustion.
A primary air stream may be allowed to flow into the two venturi inlets
(operation 320).
For example, the velocity of the fuel stream may draw air into the venturi
inlets. The
velocity of the primary air stream may be increased by the velocity of the
fuel stream, in
some implementations. As illustrated in Figures 1A -1B, the primary air stream
may
include air drawn from the area proximate a venturi inlet. The amount of air
allowed to
flow into the venturi inlets may be based on characteristics of the venturi
inlet (e.g.,
shape, size, and/or coatings on the venturi inlet). In some implementations, a
cross-
section of a flow profile of fluid entering the venturi inlet may resemble an
inner fuel
stream at least partially surrounded by an annular ring of the air stream.
At least a portion of the primary air stream and at least a portion of the
fuel stream may
be allowed to mix (operation 330). Mixing may occur between the streams. For
example, the fuel and the air may mix in along the boundaries between the two
fluids.
The fuel and air streams may mix along a length of the body (e.g., mixing
length). The
mixed stream (e.g., stream including a mix of fuel and air) may continue to
mix along a
length of the body until the fuel is combusted.
The mixed stream may be allowed to flow to the burner heads of the burner
(operation
340). For example, the mixed stream may flow from the arms of the body into a
burner
region. From the burner region the mixed stream may flow out of the openings
of the
burner heads.
At least partial combustion of the mixed stream may be allowed proximate the
burner
heads (operation 350). For example, a flame may be generated proximate a
burner
head (e.g., an outer top surface of the burner head). The fuel in the mixed
stream may
be partially or fully combusted.
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Process 300 may be implemented by various systems, such as systems 100, 101.
In
addition, various operations may be added, deleted, and/or modified. In
some
implementations, process 300 may be performed in combination with other
processes
such as process 200. For example, a burner with a single burner head may be
utilized.
In some implementations, the velocity of the fuel stream may generate the
primary air
stream. For example, the velocity of the fuel stream may create a velocity in
the primary
air stream and in a similar direction as the velocity of the fuel stream. In
some
implementations, the primary air stream may have a greater flow rate than the
secondary air stream.
In some implementations, a secondary air stream may be allowed to mix with the
mixed
stream proximate the burner heads. For example, the secondary air stream may
include
air proximate the burner heads and as the mixed stream exits the burner head
and/or
the fuel in the mixed stream is combusted, the secondary air stream may mix
with the
mixed stream. As illustrated in Figures 1A-1B, the secondary air stream may
include air
drawn from the area proximate one or more of the burner heads. The secondary
air
stream may decrease the amount incomplete combustion. The amount of secondary
air
stream allowed to mix may be based at least partially on burner height,
clearance,
and/or distances between burners.
In some implementations, the amount of primary air stream may be increased
and/or the
amount of primary air stream allowed to mix with the fuel stream may be
increased (e.g.,
when compared with a single venturi inlet burner that is able to process a
similar flow
rate of fuel). For example, since a larger exterior surface area of the fuel
stream may be
in contact with the primary air stream when using two venturi inlets (e.g., as
opposed to
a single larger venturi inlet that may be able to process a similar fuel flow
rate), mixing
may be improved. In some implementations, a greater total amount of primary
air
stream (e.g., when compared with a single venturi inlet designed to
accommodate a
similar fuel flow rate) may be allowed to enter the first and second venturi
inlets, which
may improve combustion.
In some implementations, utilizing the double venturi inlet burner may improve
combustion (e.g., allow more complete combustion of fuel) when compared with a
single
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venturi inlet design for handling a similar total flow rate of fuel. For
example, since
mixing with the primary air stream may be increased with the double venturi
inlet burner,
more combustion may be improved (e.g., when compared with a single venturi
inlet
burner).
In some implementations, the effect of orientation of the burner (e.g.,
disposing the
burner vertically, at an angle, and/or horizontally) may be minimized with the
double
venturi burner. For example, when aligning a burner with a furnace, the burner
may be
disposed in a vertical or other orientation. Gravity may affect mixing
properties and/or
flow rates in single venturi inlet burners. However, since pressure
distribution in the
burner may be maintained within a smaller range than when using a single
venturi inlet
(e.g., designed to process a similar amount of fuel), the orientation of the
burner may not
substantially impact the performance of the burner.
Although users have been described as a human, a user may be a person, a group
of
people, a person or persons interacting with one or more computers, and/or a
computer
system.
It is to be understood the implementations are not limited to particular
systems or
processes described which may, of course, vary. It is also to be understood
that the
terminology used herein is for the purpose of describing particular
implementations only,
and is not intended to be limiting. As used in this specification, the
singular forms "a",
"an" and "the" include plural referents unless the content clearly indicates
otherwise.
Thus, for example, reference to "an inlet" includes a combination of two or
more inlets;
and, reference to "a burner head" includes different types and/or combinations
of burner
heads. Reference to "a fuel" may include a combination of two or more fuels.
As
another example, "coupling" includes direct and/or indirect coupling of
members.
Although the present disclosure has been described in detail, it should be
understood
that various changes, substitutions and alterations may be made herein without
departing from the scope of the disclosure. Moreover, the scope of the present
application is not intended to be limited to the particular embodiments of the
process,
machine, manufacture, composition of matter, means, methods and steps
described in
the specification. As one of ordinary skill in the
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art will readily appreciate from the disclosure, processes, machines,
manufacture,
compositions of matter, means, methods, or steps, presently existing or later
to be
developed that perform substantially the same function or achieve
substantially the
same result as the corresponding embodiments described herein may be utilized
according to the present disclosure. Accordingly, the appended claims are
intended to
include within their scope such processes, machines, manufacture, compositions
of
matter, means, methods, or steps.
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