U.S. patent application number 14/258191 was filed with the patent office on 2015-10-22 for minimum input air providing device and method.
This patent application is currently assigned to The Marley-Wylain Company. The applicant listed for this patent is The Marley-Wylain Company. Invention is credited to Neil Butt, Ryan Hardesty, Aaron Smith.
Application Number | 20150300640 14/258191 |
Document ID | / |
Family ID | 54321710 |
Filed Date | 2015-10-22 |
United States Patent
Application |
20150300640 |
Kind Code |
A1 |
Smith; Aaron ; et
al. |
October 22, 2015 |
MINIMUM INPUT AIR PROVIDING DEVICE AND METHOD
Abstract
An airflow proving device is provided. The device includes: a
housing defining an airflow pathway; a first chamber within the
housing; a second chamber within the housing located downstream in
the flow pathway from the first chamber; structure in the housing
defining an orifice, the orifice providing fluid communication
between the first and second chamber and being part of the fluid
pathway; and a pressure measuring device having a first sensor
configured to monitor a pressure in the first chamber and a second
sensor configured to monitor a pressure in the second chamber.
Inventors: |
Smith; Aaron; (La Porte,
IN) ; Butt; Neil; (Rolling Prairie, IN) ;
Hardesty; Ryan; (Valparaiso, IN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
The Marley-Wylain Company |
Michigan City |
IN |
US |
|
|
Assignee: |
The Marley-Wylain Company
Michigan City
IN
|
Family ID: |
54321710 |
Appl. No.: |
14/258191 |
Filed: |
April 22, 2014 |
Current U.S.
Class: |
431/12 ; 110/189;
431/14 |
Current CPC
Class: |
F23N 2225/06 20200101;
F23N 3/082 20130101; F23N 5/18 20130101 |
International
Class: |
F23N 3/00 20060101
F23N003/00; F23N 5/18 20060101 F23N005/18; F23N 3/08 20060101
F23N003/08 |
Claims
1. An airflow proving device comprising: a housing defining an
airflow pathway; a first chamber within the housing; a second
chamber within the housing located downstream in the flow pathway
from the first chamber; structure in the housing defining an
orifice, the orifice providing fluid communication between the
first and second chamber and being part of the fluid pathway; and a
pressure measuring device having a first sensor configured to
monitor a pressure in the first chamber and a second sensor
configured to monitor a pressure in the second chamber.
2. The airflow proving device of claim 1, wherein the pressure
measuring device is a pressure switch.
3. The airflow proving device of claim 2, further comprising a
controller operatively connected to the pressure measuring device
and operatively connected with a blower fluidly connected to the
airflow pathway.
4. The airflow proving device of claim 3, wherein the controller is
configured to turn off the blower if the pressure switch is
tripped.
5. The airflow proving device of claim 1, further comprising a
system to which the airflow proving device is part of the system
further comprising: a controller operatively connected to the
pressure measuring device; a fuel mixing device configured to add
fuel to air in the airflow; a blower configured to move the air and
fuel along the airflow pathway; and a combustion device configured
to receive the air/fuel mixture from the airflow pathway and burn
the fuel in the air.
6. The airflow proving device of claim 5, wherein the fuel mixing
device is operatively connected to the controller and the
controller is configured to adjust an air/fuel mixture in the
airflow.
7. The airflow proving device of claim 5, wherein the controller is
operatively connected to the blower and is configured to turn on
and off the blower.
8. The airflow proving device of claim 5, wherein the controller is
operatively connected to the blower and is configured to adjust a
speed associated with the blower.
9. The airflow proving device of claim 5, wherein the controller is
operatively connected to the combustion device and is configured to
control combustion occurring within the combustion device.
10. The airflow proving device of claim 1, wherein the pressure
measuring device is a pressure transducer.
11. The airflow proving device of claim 10, further comprising a
controller operatively connected to the pressure measuring device
and operatively connected with a blower fluidly connected to the
airflow pathway and the controller is configured to adjust a speed
associated with the blower.
12. The airflow proving device of claim 1, further comprising a
controller operatively connected to the pressure measuring device
and the blower wherein the controller is configured to adjust the
speed associated with the blower if a difference in pressure
measured by the first sensor and second sensor falls below a
threshold.
13. The airflow proving device of claim 12, wherein the controller
will adjust the speed associated with the blower to be faster if a
difference in pressure measured by the first sensor and the second
sensor falls below a first threshold.
14. The air proving device of claim 13, further comprising
additional thresholds after the first threshold, wherein the
controller is configured to increase a speed associated with the
blower after the difference in pressure measured by the first
sensor and second sensor falls below each of the thresholds.
15. The air proving device of claim 14, further comprising a final
threshold and the controller is configured to shut down the blower
if the pressure measured by the first and second sensors falls
below the final threshold.
16. The air proving device of claim 12, wherein the controller will
turn off the blower if a difference in pressure measured by the
first sensor and second sensor falls below the threshold.
17. The airflow proving device of claim 12, wherein the controller
includes a timing device and the controller is further configured
to increase a speed associated with the blower when the difference
in pressure measured between the first sensor and the second sensor
falls below a threshold and if the difference in pressure measured
between the first sensor and the second sensor does not increase
past a second threshold after a set amount of time after the speed
associated with the blower has increased, then the controller will
turn off the blower.
18. The airflow proving device of claim 12, wherein the threshold
is different depending upon the current speed associated with the
blower.
19. A method for confirming airflow comprising: configuring air to
flow between a first chamber and a second chamber through an
orifice; measuring an air pressure associated with the first
chamber; measuring an air pressure associated with the second
chamber; comparing the two measured pressures against a threshold;
and adjusting a speed associated with the blower depending upon the
difference between the air pressure associated with the first
chamber and the air pressure associated with the second chamber
falls below the threshold.
20. An airflow proving device comprising: means for defining an
airflow pathway; a first chamber within the housing; a second
chamber within the housing located downstream in the flow pathway
from the first chamber; means for defining an orifice, the orifice
providing fluid communication between the first and second chamber
and being part of the fluid pathway; and means for comparing
measuring pressure having a first means for sensing a pressure in
the first chamber, and a second means for sensing pressure
associated with the second chamber.
Description
FIELD OF THE DISCLOSURE
[0001] The present disclosure relates generally to an apparatus and
method for confirming airflow through a pathway. More particularly,
the present invention relates to an apparatus and method for
confirming airflow through a system that includes a combustion
device.
BACKGROUND OF THE INVENTION
[0002] Combustion systems such as boilers, furnaces or any other
commercial or household combustion system rely on air flowing
through the system to assure proper combustion at the burner. Good
and reliable flow of air through the system aids to provide
complete combustion of the fuel. Manufacturers of equipment which
utilize combustion as an energy source are continuing to increase
the turndown ratio of that equipment. The turndown ratio is the
ratio of the minimum and maximum input rate of a particular unit.
What may be input may be air, fuel, or a combination of an air-fuel
mixture.
[0003] As the minimum input rate decreases, the ability to
accurately control the combustion process may become increasingly
difficult. When certain conditions present themselves, for example,
blocked combustion air, blocked exhaust pipes, or wind conditions
at the vent termination unit may cause the combustion process to
lose stability or efficiency. This loss in combustion may create
incomplete combustion which can create large amounts of carbon
monoxide or even loss of flame. These and other undesirable
conditions may be the result of a lack of airflow through the
combustion system. As a result, it can be difficult to ensure that
at least a minimal amount of air is, in fact, flowing through the
combustion system.
[0004] Relying on a setting for a blower to provide accurate
information regarding flow of air through the system may be
problematic. Blowers will tend to run and perhaps even increase in
speed when there are blockages of airflow through the system. As a
result, while the blower speed may provide a good approximation of
airflow during ideal conditions, blower speed does not always
provide a reliable indication of airflow during adverse conditions
such as, for example, but not limited to, blockages in the airflow
path or wind conditions at the vent termination unit. As a result,
reliance on the blower speed alone does not confirm an amount of
air flowing through the system.
[0005] Accordingly, it is desirable to provide a method and
apparatus that may provide a more reliable indication of air
flowing through the system and specifically, confirmation of a
minimum of input air flowing through the system.
SUMMARY OF THE INVENTION
[0006] The foregoing needs are met, to a great extent, by the
present invention, wherein in one aspect an apparatus is provided
that in some embodiments a method and apparatus may provide a more
reliable indication of air flowing through the system and
specifically, confirmation of a minimum of input air flowing
through the system.
[0007] In accordance with one embodiment of the present invention,
an airflow proving device is provided. The device includes: a
housing defining an airflow pathway; a first chamber within the
housing; a second chamber within the housing located downstream in
the flow pathway from the first chamber; structure in the housing
defining an orifice, the orifice providing fluid communication
between the first and second chamber and being part of the fluid
pathway; and a pressure measuring device having a first sensor
configured to monitor a pressure in the first chamber and a second
sensor configured to monitor a pressure in the second chamber.
[0008] In accordance with another embodiment of the present
invention, a method for confirming airflow is provided. The method
includes: configuring air to flow between a first chamber and a
second chamber through an orifice; measuring an air pressure
associated with the first chamber; measuring an air pressure
associated with the second chamber; comparing the two measured
pressures against a threshold; and adjusting a speed associated
with the blower depending upon the difference between the air
pressure associated with the first chamber and the air pressure
associated with the second chamber falls below the threshold.
[0009] In accordance with yet another embodiment of the present
invention, an airflow proving device is provided. The device may
include: means for defining an airflow pathway; a first chamber
within the housing; a second chamber within the housing located
downstream in the flow pathway from the first chamber; means for
defining an orifice, the orifice providing fluid communication
between the first and second chamber and being part of the fluid
pathway; and means for comparing measuring pressure having a first
means for sensing a pressure in the first chamber, and a second
means for sensing pressure associated with the second chamber.
[0010] There has thus been outlined, rather broadly, certain
embodiments of the invention in order that the detailed description
thereof herein may be better understood, and in order that the
present contribution to the art may be better appreciated. There
are, of course, additional embodiments of the invention that will
be described below and which will form the subject matter of the
claims appended hereto.
[0011] In this respect, before explaining at least one embodiment
of the invention in detail, it is to be understood that the
invention is not limited in its application to the details of
construction and to the arrangements of the components set forth in
the following description or illustrated in the drawings. The
invention is capable of embodiments in addition to those described
and of being practiced and carried out in various ways. Also, it is
to be understood that the phraseology and terminology employed
herein, as well as the abstract, are for the purpose of description
and should not be regarded as limiting.
[0012] As such, those skilled in the art will appreciate that the
conception upon which this disclosure is based may readily be
utilized as a basis for the designing of other structures, methods
and systems for carrying out the several purposes of the present
invention. It is important, therefore, that the claims be regarded
as including such equivalent constructions insofar as they do not
depart from the spirit and scope of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a schematic diagram of a combustion system
incorporating a minimum input air proving device in accordance with
the disclosure.
[0014] FIG. 2 is a schematic, cross-sectional view of a minimum
input air proving device in accordance with the disclosure.
[0015] FIG. 3 is a flowchart outlining steps for accomplishing a
method of controlling a combustion system that includes confirming
an amount of air flowing through the system in accordance with the
disclosure.
DETAILED DESCRIPTION
[0016] The invention will now be described with reference to the
drawing figures, in which like reference numerals refer to like
parts throughout. An embodiment in accordance with the present
disclosure provides a method and apparatus for determining or
verifying that there is at least a minimal airflow through the
system.
[0017] A combustion system 10 is shown in FIG. 1. The combustion
system 10 includes a controller 12 operably connected to various
components in the system 10. An airflow proving device 14 in
accordance with this disclosure is mounted in an initial portion of
an air pathway. The air flow proving device 14 includes a pressure
measuring device 15. The airflow proving device 14 has an air inlet
16 and an air outlet 18. Airflow is represented by arrows A through
the system 10. Air flows through the air inlet 16 through the
airflow proving device 14 and out the air outlet 18. The air
pathway continues through the airflow proving device 14 through a
conduit 20 into the inlet 22 of an air/fuel mixture device 24. In
the air/fuel mixture device 24, fuel is combined with the air
flowing through the airflow pathway. In some embodiments, the air
and fuel mixing may occur via a venturi-type system. In other
embodiments other ways of mixing the air and fuel together may
occur in accordance with this disclosure.
[0018] After the air and fuel have mixed in the air/fuel mixture
device 24, the air/fuel mixture will flow through the outlet 26
through the conduit 28 into the inlet 30 of the blower 32. The
blower 32 moves the air and/or air/fuel mixture through the system
10. The after the air/fuel mixture flows to the blower 32 it flows
out of the outlet 34 into the conduit 36 and into the inlet 38 of
the combustion device 42. Once the air/fuel mixture is in the
combustion device 42, it will combust as controlled by the
combustion device 42. After combustion, the exhaust gases will flow
out of the outlet 40 and through the exhaust system 41.
[0019] In some embodiments, the combustion device 42 may be a
furnace, a boiler, heater, or any other combustion device. While
the examples set forth herein primarily discuss combustion used in
domestic or commercial heat this disclosure may also be applicable
to any type of combustion device.
[0020] FIG. 2 is a close-up cutaway view of an air flow proving
device in accordance with an embodiment. The airflow proving device
14 includes a wall 50 that defines an orifice 52. The orifice 52
provides fluid communication between the inlet chamber 54 and the
outlet chamber 56. Air, as represented by arrow A, flows into the
inlet 16 and into the inlet chamber 54. The air continues to flow
through the orifice 52 into the outlet chamber 56 out of the outlet
18 and into the conduit 20 and continues along the fluid pathway as
illustrated and described with respect to FIG. 1.
[0021] The pressure measuring device 15 has two leads 46 and 48.
The lead 46 is configured to sense a pressure associated with the
air in the inlet chamber 54. The lead 48 is configured to sense an
air pressure associated with the outlet chamber 56. In embodiments
where the pressure measuring device 15 is simply a pressure switch,
if a difference between the pressure sensed by leads 46 and 48 goes
below a minimum threshold, then the pressure measuring device 15
will send a signal via connection 44 to the controller 12. In this
case, the pressure measuring device 15 acts like a pressure switch
and trips if a minimum threshold is exceeded.
[0022] In other embodiments, the pressure measuring device 15 acts
as a pressure sensor and sends signals to the controller 12 via the
connection 44 indicative of a difference in pressure detected by
leads 46 and 48.
[0023] In some embodiments, if the orifice 52 is sized
appropriately with respect to a desired airflow, as air flows
through the airflow proving device 14 as represented by arrow A,
the airflow will encounter a bottleneck at orifice 52. This will
cause pressure to decrease within chamber 56 in comparison to
chamber 54. If a lot of air is moving through the airflow proving
device 14, then there will be a large pressure difference between
chambers 54 and 56. This pressure difference will be a result of a
vacuum in chamber 56 as a result of the bottleneck of air trying to
flow through the orifice 52. If no or little air is flowing through
the airflow proving device 14 then the pressures between chambers
54 and 56, as sensed or detected by the pressure measuring the
device 15, will approach or equal a zero difference in pressure. As
a result, the higher difference in pressure detected by leads 46
and 48 will indicate higher airflow through the airflow proving
device 14. Thus, the pressure measuring device 15 can confirm by
measuring different pressures within chambers 54 and 56, whether
air is flowing through the air proving device 14.
[0024] Returning to FIG. 1, in some embodiments, the controller 12
is connected via connections 44 to the pressure measuring device
15, the air/fuel mixture device 24, the blower 32, and the
combustion device 42. In other embodiments, the controller 12 may
be connected only to the pressure measuring device 15 and the
blower 32. In other embodiments the controller 12 may be connected
to the pressure measuring device 15, the blower 32, and any other
combination of elements within the system 10.
[0025] In some embodiments, the signals received by the controller
12 from the pressure measuring device 15 will allow the controller
12 to determine whether to speed up, slow down, maintain speed, or
turn off the blower 32. In other embodiments, feedback or signals
received by the controller 12 from the pressure measuring device 15
may result in the controller 12 generating other control signals to
other components of the system 10. For example, depending on
signals received by the controller 12 from the pressure measuring
device 15, the controller 12 may give control signals to the
air/fuel mixture device 24, the blower 32, the combustion device
42, or any combination of those elements.
[0026] In some embodiments, the minimum threshold settings may be
programmed by a user or set at the factory. These settings may
remain fixed until the controller 12 is reprogrammed. In some
embodiments, control settings or present conditions at various
components such as the air/fuel mixture device 24, the blower 32,
or the combustion device 42, may result in the controller reacting
differently to signals received from the pressure measuring device
15. For example, if the blower 32 is set at a relatively slow speed
causing air and/or air/fuel mixture to flow through the system 10
at a relatively slow pace, then the controller 12 will allow the
blower 32 to operate without further signals from the controller to
change operation of the blower 32 when signals from the pressure
measuring device 15 indicate a relatively low airflow in the
airflow proving device 14. Thus, the threshold that the controller
12 uses to make decisions on whether to interfere with operation of
other components within the system 10 may depend upon the current
setting of those components. As a result, if, for example, the
blower 32 is operating at a relatively high speed, then the
controller 12 will demand a relatively high amount of air flow
through the airflow proving device 14 as detected by the pressure
monitoring device 15, but if the blower 32 is operating at a
relatively low speed, then the controller 12 will lower the
threshold of detective air flowing through the air proving device
14 before interfering with operation blower 32 or any of the other
components in the system 10. One of ordinary skill in the art,
after reviewing this disclosure, will understand what thresholds to
program into the controller to achieve desired system
performance.
[0027] FIG. 3 illustrates an example method that may be
accomplished by the system 10. For example in step S1, the system
10 measures pressure. This can be accomplished by the pressure
measuring device 15 sensing a difference in pressure within the
chambers 54 and 56. In step S2, the controller 12 may send a
control signal to the blower 32. This control signal may, in some
embodiments, be to shut down the blower 32. In other embodiments,
this control signal may be to speed up or slow down the blower 32.
In an optional step S3, depending upon the measured pressure done
at step S1, the controller 12 may send a control signal to other
system components such as the combustion device 42 and/or the
air/fuel mixture device 24.
[0028] In embodiments where the pressure measuring device 15 is a
pressure switch, if there is little or no difference (the
difference falls below a minimal threshold) the pressure switch 15
may send a signal to the controller 12 indicating such. The
controller 12 will then detect that the airflow through the system
10 is below a minimum threshold and then shut down the blower 32
and or combustion device 42. In some embodiments, the controller 12
may also shut down other components such as the air/fuel mixture
device 24. In some embodiments where the pressure measuring device
15 is a pressure switch 15 and the difference in pressure detected
in chambers 54 and 56 falls below a minimum threshold, the
controller 12 may increase the speed of the blower 32 and wait a
preset amount of time to see if there is a pressure increase in
chamber 54 with respect to chamber 56. If the difference in
pressure between chambers 54 and 56 still remain below the minimum
threshold after the set amount of time, the controller 12 may then
shut down any, all, or some of the other components in the system
10 such as, but not limited to, the blower 32, the combustion
device 42, and the air/fuel mixture device 24.
[0029] In embodiments where the pressure measuring device 15 is a
pressure sensor, then the controller 12 may have different minimum
threshold differences in pressure between the chambers 54 and 56
depending upon the speed of the blower 32. If the detected
difference in pressure falls below a minimum threshold for a given
speed, the controller 12 may shut down one, all, or some of the
components of the system such as, but not limited to, the blower
32, the combustion device 42, or the air/fuel mixture device 24. In
other embodiments, when the pressure difference between the
chambers 54 and 56 fall below a minimum threshold for a given
blower speed, the controller 12 may increase the blower speed and
await a set amount of time and re-measure the difference in
pressures between the chambers 54 and 56. If the pressure
differential is still below minimum threshold, then the controller
12 may shut down any, all, or portions of the system such as, but
not limited to, the blower 32, the combustion device 42, and/or the
air/fuel mixture device 24.
[0030] In some embodiments, when the detected pressure differential
between the chambers 54 and 56 falls below a minimum threshold, the
controller 12 may also set off an alarm indicator in addition to
shutting down various components of the system 10.
[0031] After reviewing this disclosure, one of ordinary skill in
the art will understand what minimum thresholds should be for a
given system 10. The system operator will also understand what time
periods are appropriate, if any, for measuring the pressure
differential between chambers 54 and 56 after a first control
signal has been sent. One of ordinary skill in the art, after
viewing this disclosure, will also understand what size the orifice
52 should be for a specific system 10. Other dimensions and
settings will also be understood.
[0032] Although an example of the system is shown and described,
for home or commercial heating systems, it will be appreciated that
other combustion systems can use features discussed herein.
[0033] The many features and advantages of the invention are
apparent from the detailed specification, and thus, it is intended
by the appended claims to cover all such features and advantages of
the invention which fall within the true spirit and scope of the
invention. Further, since numerous modifications and variations
will readily occur to those skilled in the art, it is not desired
to limit the invention to the exact construction and operation
illustrated and described. Accordingly, all suitable modifications
and equivalents may be resorted to, falling within the scope of the
invention.
* * * * *