U.S. patent application number 12/320426 was filed with the patent office on 2010-07-29 for exhaust system thermal enclosure.
This patent application is currently assigned to Caterpillar Inc. Invention is credited to Eric J. Charles, Jack A. Merchant, Paul F. Olsen.
Application Number | 20100186381 12/320426 |
Document ID | / |
Family ID | 42353011 |
Filed Date | 2010-07-29 |
United States Patent
Application |
20100186381 |
Kind Code |
A1 |
Charles; Eric J. ; et
al. |
July 29, 2010 |
Exhaust system thermal enclosure
Abstract
An exhaust system for a power system contained in an engine
compartment. The exhaust system includes a mount for two or more
exhaust treatment devices and an enclosure surrounding the two or
more exhaust treatment devices. The enclosure defines a space with
a higher temperature than a space defined by the engine compartment
during steady state operation of the power system. At least one
electronic or fluid device is coupled to the enclosure or mount and
located on an exterior of the enclosure.
Inventors: |
Charles; Eric J.; (Peoria,
IL) ; Merchant; Jack A.; (Peoria, IL) ; Olsen;
Paul F.; (Chillicothe, IL) |
Correspondence
Address: |
CATERPILLAR/FINNEGAN, HENDERSON, L.L.P.
901 New York Avenue, NW
WASHINGTON
DC
20001-4413
US
|
Assignee: |
Caterpillar Inc
Peoria
IL
|
Family ID: |
42353011 |
Appl. No.: |
12/320426 |
Filed: |
January 26, 2009 |
Current U.S.
Class: |
60/282 ;
60/311 |
Current CPC
Class: |
Y02T 10/12 20130101;
F01N 3/035 20130101; F01N 3/2066 20130101; Y02T 10/24 20130101;
F01N 13/14 20130101; F01N 3/10 20130101; F01N 3/025 20130101; F01N
13/102 20130101 |
Class at
Publication: |
60/282 ;
60/311 |
International
Class: |
F01N 3/00 20060101
F01N003/00; F01N 3/02 20060101 F01N003/02 |
Claims
1. A portion of an exhaust system for a power system contained in a
engine compartment, comprising: a mount for two or more exhaust
treatment devices; an enclosure surrounding the two or more exhaust
treatment devices and defining a space with a higher temperature
than a space defined by the engine compartment during steady state
operation of the power system; and at least one of an electronic
and fluid device coupled to the enclosure or mount and located on
an exterior of the enclosure.
2. The exhaust system of claim 1, further including a plate coupled
to the enclosure or mount and supporting the at least one
electronic or fluid device.
3. The exhaust system of claim 1, wherein the at least one
electronic or fluid device connects to one of the two or more
exhaust treatment devices.
4. The exhaust system of claim 1, wherein one of the two or more
exhaust treatment devices includes a diesel particulate filter and
one of the two or more exhaust treatment devices includes a
regeneration device.
5. The exhaust system of claim 4, wherein a head portion of the
regeneration device is not surrounded by the enclosure.
6. The exhaust system of claim 5, wherein the at least one
electronic or fluid device connects to the head portion of the
regeneration device.
7. The exhaust system of claim 5, wherein the at least one fluid
device includes fuel or combustion air used by the regeneration
device.
8. An enclosure surrounding two or more exhaust treatment devices
but not surrounding the engine, the enclosure comprising: at least
one removable panel to provide access to at least one of the two or
more exhaust treatment devices.
9. The enclosure of claim 8, wherein the enclosure includes at
least a front, a back, a top, a bottom, a first side, and a second
side to form a box structure.
10. The enclosure claim 8, wherein at least one removable panel is
a port configured to provide access to a sensor used in connection
with one of the two or more aftertreatment devices.
11. The enclosure claim 8, wherein one of the two or more exhaust
treatment devices includes a diesel particulate filter and one of
the two or more exhaust treatment devices includes a regeneration
device.
12. The enclosure claim 11, wherein at least one removable panel is
configured to provide access to the regeneration device.
13. The enclosure of claim 11 wherein at least one removable panel
is configured to provide access to the diesel particulate
filter.
14. An enclosure surrounding two or more exhaust treatment devices
supported on a mount, the enclosure comprising: at least one mount
opening configured to expose a footing of the mount.
15. The enclosure of claim 14 wherein the mount openings are
located on a bottom of the enclosure.
16. The enclosure of claim 14 wherein the footings are mounted to a
machine.
17. The enclosure of claim 14 wherein the footings are mounted to
an engine.
18. The enclosure of claim 14 further including: an exhaust conduit
configured to receive exhaust from an engine.
19. The enclosure of claim 14 further including: an exit conduit
configured to deliver exhaust to the atmosphere.
20. The enclosure of claim 14 not surrounding an engine.
Description
TECHNICAL FIELD
[0001] The present disclosure relates generally to an enclosure for
emissions system components and, more particularly, to a thermally
insulating enclosure.
BACKGROUND
[0002] Conventional power systems for engines, factories, and power
plants produce emissions that contain a variety of pollutants.
These pollutants may include, for example, particulate matter
(e.g., soot), nitrogen oxides (NOx), and sulfur compounds. Due to
heightened environmental concerns, engine exhaust emission
standards have become increasingly stringent. In order to comply
with emission standards, machine manufactures have developed and
implemented a variety of exhaust treatment components to reduce
pollutants in exhaust gas prior to the exhaust gas being released
into the atmosphere.
[0003] The exhaust treatment components may include, for example, a
diesel particulate filter, a selective catalytic reduction device,
a diesel oxidation catalyst, a heat source for regeneration of the
diesel particulate filter, a muffler, and other similar components.
Packaging of these exhaust treatment components is difficult and is
often particularly difficult given the temperatures or heat
involved. The devises and environment surrounding these exhaust
treatment components may not be able to withstand this heat.
[0004] U.S. Pat. No. 7,127,884 (the '884 patent) describes multiple
catalytic converter elements in a housing. The housing includes a
jacket with a double wall.
SUMMARY
[0005] In one aspect, the present disclosure provides an exhaust
system for a power system contained in an engine compartment. The
exhaust system includes a mount for two or more exhaust treatment
devices and an enclosure surrounding the two or more exhaust
treatment devices. In another aspect, the enclosure defines a space
with a higher temperature than a space defined by the engine
compartment during steady state operation of the power system. In
yet another aspect, at least one electronic or fluid device is
coupled to the enclosure or mount and located on an exterior of the
enclosure.
[0006] Other features and aspects of this disclosure will be
apparent from the following description and the accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a diagrammatic view of a power system including an
engine and an exhaust system in an enclosure;
[0008] FIG. 2 is a diagrammatic view of a module with the exhaust
treatment devices on a mount;
[0009] FIG. 3 is a diagrammatic view of the mount to receive the
exhaust treatment devices;
[0010] FIG. 4 is a diagrammatic view of the module in the
enclosure;
[0011] FIG. 5 is a diagrammatic view of the enclosure from FIG. 4
rotated;
[0012] FIG. 6 is a diagrammatic view of the bottom of the enclosure
from FIG. 4;
[0013] FIG. 7 is a diagrammatic view of the enclosure from FIG. 4
with a top front panel, bottom front panel, and plug removed;
[0014] FIG. 8 is a diagrammatic view of a side of the enclosure
from FIG. 4 with a side panel removed; and
[0015] FIG. 9 is a cross-sectional view of the enclosure.
DETAILED DESCRIPTION
[0016] As seen in FIG. 1, a power system 10 is contained inside an
engine compartment 11. The power system 10 includes an engine 12
and an exhaust system 14 to treat an exhaust stream 13 produced by
the engine 12. Engine 12 may receive air from an air cleaner 15.
The exhaust stream 13 exits the engine 12 from an exhaust conduit
16 to enter the exhaust system 14. The engine 12 may include other
features not shown, such as fuel systems, air systems, cooling
systems, peripheries, drivetrain components, turbochargers, etc.
The engine 12 may be any type of engine (internal combustion, gas,
diesel, gaseous fuel, natural gas, propane, etc.), may be of any
size, with any number of cylinders, and in any configuration ("V,"
in-line, radial, etc.). The engine 12 may be used to power any
machine or other device, including on-highway trucks or vehicles,
off-highway trucks or machines, earth moving equipment, generators,
aerospace applications, locomotive applications, marine
applications, pumps, stationary equipment, or other engine powered
applications.
[0017] The engine compartment 11 is the portion of the machine or
other device that contains the power system 10. The walls of the
engine compartment 11 define a compartment interior space 17
inside, where the power system 10 is located. The engine
compartment 11 may include the machine's hood and engine's
enclosure. The engine compartment 11 may be open on one or more
sides or may fully surround the power system 10. The engine
compartment 11 may house additional components in addition to the
power system 10. Portions of the power system 10 may also extend
beyond the engine compartment 11. The engine compartment 11 may
also have one or more radiators or other heat exchangers included
in its walls or otherwise located in or outside the engine
compartment 11.
[0018] The exhaust system 14 includes an aftertreatment or
component module 18 and enclosure 19. Seen best in FIG. 2, the
module 18 may include electronics and fluids 20, plate 21, cradle
or mount 22, conduits 24, and first, second, third, and fourth
exhaust treatment devices 26, 28, 30, and 32. The module 18 may be
designed to hold more or less than four exhaust treatment devices
26, 28, 30, and 32.
[0019] Exhaust treatment devices 26, 28, 30, and 32 may be devices
configured to reduce emissions of harmful gasses, particulate
matter, and/or noise emitted from engine 12. Each exhaust treatment
device 26, 28, 30, and 32 may embody, for example, a diesel
oxidation catalyst (DOC), a particulate filter (PF or DPF), a
selective catalytic reduction (SCR) device, a lean NOx trap (LNT),
a muffler, a DPF regeneration device, a reductant mixing device,
connection tube, or any other exhaust treatment or handling device
known in the art.
[0020] Electronics and fluids 20 may be configured to monitor
and/or control operation of exhaust treatment devices 26, 28, 30,
and 32. Electronics 20 may include one or more electronic devices,
such as, for example, sensors, microprocessors, power supply
circuitry, signal conditioning circuitry, actuator driving
circuitry, and/or other types of electronics and circuitry known in
the art. For example, electronics 20 may include a microprocessor
and other data processing hardware configured to control injection
of a reductant into one of exhaust treatment devices 26, 28, 30,
and 32 (e.g., reductant for SCR or LNT). Electronics 20 may also
include a microprocessor and other data processing hardware
configured to control a regeneration process for one of exhaust
treatment devices 26, 28, 30, and 32 (e.g., regeneration of DPF).
Fluids 20 may include combustion air, fuel, reductant or other
fluid used by the exhaust treatment devices 26, 28, 30, and 32.
[0021] At least a portion of the electronics and fluids 20 may be
installed on the plate 21. The plate 21 may be positioned outside
or inside the enclosure 19. Portions of the electronics and fluids
20 may also be located inside or outside the enclosure 19. The
plate 21 may be coupled or mounted to the mount 22 or enclosure
19.
[0022] As shown in FIG. 3, mount 22 is a device configured to
support one or more exhaust treatment devices 26, 28, 30, and 32.
Specifically, mount 22 may be configured to secure exhaust
treatment devices 26, 28, 30, and 32 in a compact configuration.
Mount 22 may be designed to locate exhaust treatment devices 26,
28, 30, and 32 in a parallel orientation relative to each
other.
[0023] Mount 22 may include a first bracket 34 and a second bracket
36. First bracket 34 and second bracket 36 may be oriented parallel
but spaced apart from each other. First bracket 34 may be coupled
to second bracket 36 using one or more rigid cross members 38.
Cross members 38 may attach to first and second brackets 34 and 36
via mechanical fasteners (e.g., bolts, screws, rivets, etc.),
welding, brazing, or any other joining process known in the art.
Alternatively, first bracket 34, second bracket 36, and cross
members 38 may be formed as a single casting.
[0024] Each of first and second brackets 34 and 36 may include a
first support surface 40. First support surface 40 of first bracket
34 and first support surface 40 of second bracket 36 may be
configured to support each end of fourth exhaust treatment device
32. Each of first and second brackets 34 and 36 may also include a
second support surface 42. Second support surface 42 of first
bracket 34 and second support surface 42 of second bracket 36 may
be configured to support each end of second exhaust treatment
device 28. In addition to connecting first and second brackets 34
and 36, one or more of cross members 38 may be configured to
support a middle portion of fourth exhaust treatment device 32
and/or second exhaust treatment device 28.
[0025] It is contemplated that a geometry of first support surface
40 may be shaped to match an outer geometry of fourth exhaust
treatment device 32 and a geometry of second support surface 42 may
be shaped to match an outer geometry of second exhaust treatment
device 28. For example, when fourth and second exhaust treatment
devices 32 and 28 are shaped as canisters, first and second support
surfaces 40 and 42 may have generally arcuate surfaces with
substantially the same radii of curvature as fourth and second
exhaust treatment devices 32 and 28, respectively.
[0026] Mount 22 may also include an aperture 44 in first bracket 34
and second bracket 36. Aperture 44 may define a third support
surface 46. Third support surface 46 of apertures 44 may be
configured to support, for example, each end of first exhaust
treatment device 26. Exhaust treatment devices 26, 28, 30, or 32
may be secured to the mount 22 via clamps, bolts, welding, or bands
48. The exhaust treatment devices 26, 28, 30, and 32 may be fluidly
coupled together via conduits 24. The exhaust stream 13 exits the
module 18 through exit conduit 49.
[0027] In the current exemplary embodiment, the second exhaust
treatment device 28 may embody a DPF and the first exhaust
treatment device 26 may embody a regeneration device for the DPF.
This regeneration device may include a fuel fired burner or other
heat source. The second exhaust treatment device 28 may also embody
a DOC, possibly in addition to the DPF. The third exhaust treatment
device 30 may embody a connection tube and the fourth exhaust
treatment device 32 may embody a muffler. The fourth exhaust
treatment device 32 may also embody an SCR device, and reductant
may be injected and mixed in third exhaust treatment device 30.
[0028] Mount 22 may include a base portion 50 with one or more
mounting footings 52. Each footing 52 may be configured to mount to
the engine 12 or machine.
[0029] The enclosure 19 provides a degree of thermal isolation from
the surrounding environment, devices, and electronics and fluids
20. The enclosure 19 may be designed to minimize ventilation to
achieve near total encapsulation. In one embodiment, however, vents
53 may be added to provide ventilation as needed for heat
dissipation if the temperature inside the enclosure 19 would reach
a limit.
[0030] The enclosure 19 may include a front 54, a back 56, a top
58, a bottom 60, a first side 61, and a second side 62 to form a
box structure. The enclosure 19 defines an enclosure interior space
63 inside, where the module 18 is located.
[0031] The exit conduit 49 may exit the enclosure 19 through an
exit opening 64. The exit opening 64 may be located in the top 58
of the enclosure 19 or elsewhere as needed to route the exhaust
stream 13 to the atmosphere. The exhaust conduit 16 may enter the
enclosure 19 through an entrance opening 66. The entrance opening
66 may be located in the bottom 60 of the enclosure 19 or elsewhere
as needed to route the exhaust stream 13 to the first exhaust
treatment device 26.
[0032] As seen in FIGS. 4 and 5, the electronics and fluids 20 may
be mounted or at least partially located on an outside or exterior
68 of the enclosure 19. The electronics and fluids 20 may also be
routed to run along the exterior 68. A head portion 70 of the first
exhaust treatment device 26 may be exposed by the enclosure 19. The
electronics and fluids 20 required for the first exhaust treatment
device 26 may connect at this exposed head portion 70, thereby
avoiding the heat inside the enclosure 19.
[0033] The electronics and fluids 20 may also enter the enclosure
19 through ports 72 or other openings. These electronics and fluids
20 may be used for sensing or introducing reductants. If included,
the plate 21 may also be outside the enclosure 19 and may be
coupled to the mount 22.
[0034] FIG. 6 shows the enclosure 19 may include mount openings 74.
The mount openings 74 expose the footings 52 or another part of the
base portion 50, providing access for the exhaust system 14 to be
mounted.
[0035] Portions or panels of the enclosure 19 may be removable to
allow servicing of the module 18 and exhaust treatment devices 26,
28, 30, and 32. Fig. 7 shows a removable front top panel 76 and
bottom front panel 78 to be removable from the other parts of the
enclosure 19. In one embodiment, the front top panel 76 and bottom
front panel 78 are located to provide access to a DPF portion 79 of
the second exhaust treatment device 28. The DPF may have to be
periodically removed for service. The front top panel 76 and bottom
front panel 78 may provide access to the DPF or second exhaust
treatment device 28. The DPF portion 79 may be located between
bands 48 so that the DPF portion is removable from the second
exhaust treatment device 28 for service.
[0036] FIG. 7 also shows ports 72 may be removable. FIG. 8 shows a
side panel 80 may also be removable to provide access to the
regeneration device or first exhaust treatment device 26 and its
associated electronics and fluids 20. Other portions of the
enclosure 19 may be removable as needed for assembly and service.
Any portion of the front 54, back 56, top 58, bottom 60, first side
61, or second side 62 may be removable.
[0037] The removable panels may be held in place with fasteners 82.
The fasteners 82 may be bolts, 90 degree quick turn latches, clips,
or other fastening device. The removable panels may rest on over
hanging portions of the surrounding portions of the enclosure 19.
Support tabs may also be added for the removable panels to rest on
and prevent from falling into the enclosure 19.
[0038] Because access to the enclosure 19 may be limited in the
machine, the removable panels may be designed so that they can be
removed from a given direction for accessibility. Additionally, the
fasteners 82 may be located so that they can be accessed from a
given direction. This given direction may provide access from the
top, bottom, front, back, or side. In one embodiment, for example,
the front top panel 76 and bottom front panel 78 are removable and
assessable from the front without access needed from the top.
[0039] FIG. 9 illustrates how the enclosure 19 may be constructed.
An outer shell 90 may form the exterior 68, an inner shell 92 may
form an interior 94. An insulation 96 may be between the outer
shell 90 and inner shell 92. An alternative embodiment may not
include an outer shell 90 or inner shell 92 depending on the
durability of the insulation 96. The front 54, back 56, top 58,
bottom 60, first side 61, or second side 62 may overlap at
overlapping regions 98 to form the enclosure 19 structure.
[0040] The outer shell 90 and inner shell 92 may be a material of
composition and size to withstand the temperature and stress
involved. In one embodiment, the outer shell 90 may be aluminized
steel, sheet metal, or 321 or 316 corrosion resistant steel (CRS)
and may be roughly 1.5 mm thick. The inner shell 92 may be a glass
silica fiber or high efficiency paper based material and may have
adhesive and may be roughly 12 mm thick and also serve as the
insulation 96.
[0041] The front 54, back 56, top 58, bottom 60, first side 61, or
second side 62 outer shells 90 may also include overlapping outer
shell regions 100 to form the enclosure 19 structure. The outer
shell 90 may also include containment clips 102. The containment
clips 102 may extend or fold over from the edge of the outer shell
90 and over the interior 94 to hold the inner shell 92 or
insulation 96 in place. Alternative embodiments may include
fasteners to hold the outer shell 90, inner shell 92, and
insulation 96 in place.
[0042] The spacing between the enclosure 19 and module 18 may be
designed to avoid direct contact while limited for packing in the
machine. In one embodiment, the enclosure 19 is spaced roughly 1
inch from the module 18. In other embodiments, the enclosure 19 may
be in contact with the module 18 or spaced apart from the module 18
at a greater distance. The contour, shape, and size of enclosure 19
and module 18 may be designed to achieve the desired spacing.
INDUSTRIAL APPLICABILITY
[0043] Achieving a limited enclosure 19 exterior 68 temperature may
be desired in certain machine application. For example, many
machine applications are exposed to a variety of combustibles.
Other machine applications may involve personnel near the power
system 10.
[0044] The design of the enclosure 19 is developed to achieve a
given exterior 68 or skin temperature as required by the machine
application during normal operation conditions of the power system
10. In one embodiment, the design may be sufficient to achieve an
exterior 68 temperature of roughly 200 degrees Celsius. This
exterior 68 temperature may be achievable with a temperature of the
exhaust stream 13 at the exit conduit 49 of roughly 550 degrees
Celsius and a temperature surrounding the enclosure of 80 degrees
Celsius.
[0045] The enclosure 19 insulates the module 18 from its
surroundings. As such, during steady state operation of the power
system 10, the temperature in the enclosure interior space 63 is
higher than the temperature in the compartment interior space 17.
Accordingly, the enclosure 19 protects the components located
outside or exterior to the enclosure 19 from thermal damage. The
limited exterior 68 temperatures and enclosure interior space 63
temperatures provided by the enclosure 19 may specifically protect
the electronics and fluids 20.
[0046] The steady state operation of the power system 10 may be
considered the time when the temperature in the enclosure interior
space 63 and compartment interior space 17 both reach a
substantially maximum and constant temperature. The enclosure 19
may also acoustically insulate the module 18 from its
surroundings.
[0047] Although the embodiments of this disclosure as described
herein may be incorporated without departing from the scope of the
following claims, it will be apparent to those skilled in the art
that various modifications and variations can be made. Other
embodiments will be apparent to those skilled in the art from
consideration of the specification and practice of the disclosure.
It is intended that the specification and examples be considered as
exemplary only, with a true scope being indicated by the following
claims and their equivalents. What is claimed is:
* * * * *