U.S. patent application number 14/517378 was filed with the patent office on 2016-04-21 for diesel exhaust fluid pump electronics and tank unit cooling.
This patent application is currently assigned to CATERPILLAR INC.. The applicant listed for this patent is CATERPILLAR INC.. Invention is credited to Leon J. Bezaire, Mohammed Ohidul Islam, Rajesh Kandibanda, Krishna N. Pai, Siddartha Veliganti Reddy.
Application Number | 20160108793 14/517378 |
Document ID | / |
Family ID | 55748654 |
Filed Date | 2016-04-21 |
United States Patent
Application |
20160108793 |
Kind Code |
A1 |
Bezaire; Leon J. ; et
al. |
April 21, 2016 |
Diesel Exhaust Fluid Pump Electronics and Tank Unit Cooling
Abstract
A housing for an exhaust fluid pump electronics and tank unit
may include a chamber and a deflection flange. The housing may
include a removable cover including a vent and a cover flange. The
cover flange may be removably coupled to the deflection flange. A
duct may be disposed on the housing and capable of fluidly
communicating the chamber to a negative pressure source.
Inventors: |
Bezaire; Leon J.; (Forsyth,
IL) ; Kandibanda; Rajesh; (Gilroy, CA) ;
Islam; Mohammed Ohidul; (Champaign, IL) ; Pai;
Krishna N.; (Decatur, IL) ; Reddy; Siddartha
Veliganti; (Chambersburg, PA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
CATERPILLAR INC. |
Peoria |
IL |
US |
|
|
Assignee: |
CATERPILLAR INC.
Peoria
IL
|
Family ID: |
55748654 |
Appl. No.: |
14/517378 |
Filed: |
October 17, 2014 |
Current U.S.
Class: |
312/236 ;
312/293.3 |
Current CPC
Class: |
F01N 13/14 20130101;
F01N 2610/1433 20130101; F01N 2610/1406 20130101 |
International
Class: |
F01N 13/14 20060101
F01N013/14; F01N 3/021 20060101 F01N003/021; F01N 3/20 20060101
F01N003/20 |
Claims
1. A housing for an exhaust fluid pump electronics and tank unit of
a vehicle, the housing comprising: a chamber formed collectively of
a first and a second side wall, an upper wall, a lower wall, an aft
wall, and a fore wall, the first and the second side wall, the
upper wall, and the fore wall collectively forming an opening; a
deflection flange extending outwardly from each of the first and
the second side wall, the upper wall, and the fore wall proximate
the opening; a removable cover including a vent and a cover flange,
the cover flange removably coupled to the deflection flange; and a
duct disposed on the first side wall, the duct capable of fluidly
communicating the chamber to a negative pressure source.
2. The housing of claim 1, further including a ceramic wool
insulating blanket surrounding the first and the second side wall,
the upper wall, and the aft wall.
3. The housing of claim 1, wherein the cover flange includes a
gasket.
4. The housing of claim 1, further including at least one gland
plate disposed on one of the first and the second side wall, the
upper wall, and the aft wall.
5. The housing of claim 1, wherein the removable cover includes an
aperture for receiving a neck of a diesel exhaust fluid (DEF)
tank.
6. A diesel-fueled vehicle, the vehicle comprising: a housing
formed collectively of a first and a second side wall, an upper
wall, a lower wall, an aft wall, and a fore wall, the first and the
second side wall, the upper wall, and the fore wall collectively
forming an opening; a deflection flange extending outwardly from
each of the first and the second side wall, the upper wall, and the
fore wall proximate the opening; a removable cover including a vent
and a cover flange, the cover flange removably coupled to the
deflection flange; a diesel exhaust fluid (DEF) pump electronics
and tank unit (PETU) disposed in the housing; a radiator fan shroud
surrounding a radiator fan; and a duct coupling the housing to the
radiator fan shroud at a location wherein the radiator fan creates
a negative pressure.
7. The vehicle of claim 6, further including a ceramic wool
insulating blanket surrounding the housing.
8. The vehicle of claim 6, further including a clean emissions
module (CEM) disposed proximate the housing.
9. The vehicle of claim 8, further including a DEF line disposed
through the housing and connecting the DEF PETU in fluid
communication with the CEM.
10. The vehicle of claim 9, wherein the DEF line is sealed to the
housing with at least one gland plate.
11. The vehicle of claim 6, further including a bracket coupled to
the housing wherein a channel is defined between the bracket and
the deflection flange, the channel receiving a panel.
12. The vehicle of claim 6, further including coolant lines
disposed through the housing and connecting the DEF PETU in fluid
communication with an engine of the vehicle, the coolant lines
sealed to the housing with at least one gland plate.
13. The vehicle of claim 6, further including a wiring disposed
through the housing and connecting the DEF PETU in electrical
communication with an engine of the vehicle, the wiring sealed to
the housing with at least one gland plate.
14. The vehicle of claim 6, further including an elastomeric mat
disposed between the lower wall of the housing and the DEF
PETU.
15. The vehicle of claim 6, wherein the cover flange includes a
gasket.
16. The vehicle of claim 6, wherein the removable cover includes an
aperture for receiving a neck of the DEF PETU, the aperture
including a positioning seal.
17. A method of insulating and cooling a diesel exhaust fluid (DEF)
pump electronics and tank unit (PETU) from high temperatures of a
diesel-fueled vehicle, the method comprising: providing an
insulated housing to surround the DEF PETU and isolate the DEF PETU
from the high temperatures; providing a vent on a removable cover
of the insulated housing; and providing a duct on the insulated
housing to allow fluid communication between the insulated housing
and a radiator fan at a location wherein the radiator fan creates a
negative pressure that draws ambient air through the vent into the
insulated housing and through the duct.
18. The method of claim 17, further including providing a ceramic
wool insulating blanket around the insulated housing.
19. The method of claim 17, further including providing a
deflection flange on the insulated housing to redirect a hot air
flow away from the insulated housing.
20. The method of claim 17, further including providing at least
one gland plate to seal at least one line to the insulated housing,
the at least one line communicating between the DEF PETU and a
vehicle component.
Description
TECHNICAL FIELD
[0001] The present disclosure relates generally to diesel-fueled
construction vehicles and, more particularly, to diesel exhaust
fluid pump electronics and tank units for such vehicles.
BACKGROUND
[0002] Many diesel-fueled vehicles are equipped or retro-fitted to
utilize selective catalytic reduction (SCR) processes in order to
improve diesel exhaust emissions and meet regulations such as Tier
4 Final regulations. Part of the SCR process involves injecting
diesel exhaust fluid (DEF), typically a solution of urea and
deionized water, as a mist into the high-temperature exhaust stream
to reduce NO.sub.x emissions from being released into the
atmosphere. In particular, the DEF mist reacts in the exhaust
stream to form ammonia and carbon dioxide. The NO.sub.x are
catalytically reduced, within the SCR catalyst, by the ammonia into
water and nitrogen gas, which are both then released through the
vehicle exhaust.
[0003] The DEF is commonly stored in a DEF tank of a DEF pump
electronics and tank unit (DEF PETU) located on the diesel-fueled
vehicle. For some diesel-fueled vehicles, the DEF PETU is
traditionally located underneath an engine hood and proximate to
the engine and the clean emissions module (CEM), which may include
an SCR module and a diesel particulate filter (DPF) module. The
close proximity of the DEF PETU at the CEM is typically required
due to maximum distance specifications between the DEF PETU and the
DEF injector to the CEM, vehicle space limitations, and mounting
and accessing serviceability requirements. The DEF and the
electronics unit must operate below a maximum temperature. For
example, the DEF degrades faster as it is exposed to higher
temperatures and will have no material usability once exposed to
its maximum operating temperature. However, the close proximity of
the DEF PETU to the CEM and the vehicle engine exposes it to high
temperatures in excess of its maximum operating temperature.
[0004] Various approaches have been implemented to reduce or
eliminate high temperature exposure to the DEF PETU such as
utilizing an electrical motor-powered cooling fan or remotely
mounting the DEF PETU in a cooler environment far from the CEM and
vehicle engine. While effective, such approaches may incur
additional costs like requiring a larger alternator, circuit
protection, and controls for the cooling fan, requiring extra labor
intensive wiring and piping when remotely mounting the DEF PETU, or
requiring extra costs to provide remote fill provisions to fill the
tank in an inaccessible location. Accordingly, it is desirable to
maintain the DEF PETU in close proximity to the CEM and vehicle
engine while isolating it from the high temperatures.
[0005] German Patent Application No. DE102006041108A1 (the '108
application) discloses the implementation of a hood-like element to
partially cover a vehicle exhaust system to create a flow channel
between the hood-like element and the vehicle exhaust system. While
the '108 application introduces air into a partially covered
vehicle exhaust system for cooling, it fails to teach isolating and
cooling a DEF PETU from high temperatures.
SUMMARY
[0006] In accordance with an aspect of the disclosure, a housing
for an exhaust fluid pump electronics and tank unit of a vehicle
may include a chamber. The chamber may be formed collectively of a
first and a second side wall, an upper wall, a lower wall, an aft
wall, and a fore wall. The first and the second side wall, the
upper wall, and the fore wall may collectively form an opening. A
deflection flange may extend outwardly from each of the first and
the second side wall, the upper wall, and the fore wall proximate
the opening. A removable cover may include a vent and a cover
flange. The cover flange may be removably coupled to the deflection
flange. A duct may be disposed on the first side wall. The duct may
be capable of fluidly communicating the chamber to a negative
pressure source.
[0007] In accordance with another aspect of the disclosure, a
diesel-fueled vehicle may include a housing. The housing may be
formed collectively of a first and a second side wall, an upper
wall, a lower wall, an aft wall, and a fore wall. The first and the
second side wall, the upper wall, and the fore wall may
collectively form an opening. A deflection flange may extend
outwardly from each of the first and the second side wall, the
upper wall, and the fore wall proximate the opening. A removable
cover may include a vent and a cover flange. The cover flange may
be removably coupled to the deflection flange. A diesel exhaust
fluid (DEF) pump electronics and tank unit (PETU) may be disposed
in the housing. A radiator fan shroud may surround a radiator fan.
A duct may couple the housing to the radiator fan shroud at a
location wherein the radiator fan creates a negative pressure.
[0008] In accordance with yet another aspect of the disclosure, a
method of insulating and cooling a diesel exhaust fluid (DEF) pump
electronics and tank unit (PETU) from high temperatures of a
diesel-fueled vehicle is provided. The method may entail providing
an insulated housing to surround the DEF PETU and isolate the DEF
PETU from the high temperatures. Another step may be providing a
vent on a removable cover of the insulated housing. Yet another
step may be providing a duct on the insulated housing to allow
fluid communication between the insulated housing and a radiator
fan at a location wherein the radiator fan creates a negative
pressure that draws ambient air through the vent into the insulated
housing and through the duct.
[0009] Other aspects and features of the disclosed systems and
methods will be appreciated from reading the attached detailed
description in conjunction with the included drawing figures.
Moreover, selected aspects and features of one example embodiment
may be combined with various selected aspects and features of other
example embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] For further understanding of the disclosed concepts and
embodiments, reference may be made to the following detailed
description, read in connection with the drawings, wherein like
elements are numbered alike, and in which:
[0011] FIG. 1 is a perspective view of a vehicle with portions
broken away to show details in accordance with the teachings of the
present disclosure;
[0012] FIG. 2 is a perspective view of a housing for a diesel
exhaust fluid (DEF) pump electronics and tank unit adjacent a clean
emissions module (CEM) of a diesel-fueled vehicle with portions
broken away to show details in accordance with the teachings of the
present disclosure;
[0013] FIG. 3 is a perspective view of a vehicle illustrating a
housing for a DEF PETU with portions of the diesel-fueled vehicle
broken away to show details in accordance with the teaching of the
present disclosure;
[0014] FIG. 4 is a perspective view of a vehicle illustrating a
housing for a DEF PETU with the housing cover removed, constructed
in accordance with the teachings of this disclosure;
[0015] FIG. 5 is a detailed perspective view of the housing in FIG.
4, constructed in accordance with the teachings of this
disclosure;
[0016] FIG. 6 is a perspective view of the housing in FIG. 5,
constructed in accordance with the teachings of this
disclosure;
[0017] FIG. 7 is a perspective view of a housing for a DEF PETU in
association with a radiator fan of a diesel-fueled vehicle with
portion of the vehicle broken away to show details in accordance
with the teaching of this disclosure;
[0018] FIG. 8 is a top view of a mat, constructed in accordance
with the teachings of this disclosure; and
[0019] FIG. 9 is a flowchart illustrating a sample sequence of
steps which may be practiced in accordance with the teachings of
this disclosure.
[0020] It is to be noted that the appended drawings illustrate only
typical embodiments and are therefore not to be considered limiting
with respect to the scope of the disclosure or claims. Rather, the
concepts of the present disclosure may apply within other equally
effective embodiments. Moreover, the drawings are not necessarily
to scale, emphasis generally being placed upon illustrating the
principles of certain embodiments.
DETAILED DESCRIPTION
[0021] The present disclosure provides systems and methods for
insulating and protecting a diesel exhaust fluid (DEF) pump
electronics and tank unit (PETU) from high temperatures. Such
systems and methods may also induce cool ambient air to flow across
the DEF PETU to further dissipate hot air, such as thermal transfer
into the system from hot under hood air, and ensure the DEF PETU
environment operates at appropriate working temperatures.
[0022] Referring now to FIGS. 1-3, a vehicle constructed in
accordance with the present disclosure is generally referred to by
reference numeral 10. The vehicle 10 may be any type of vehicle
such as, but not limited to, diesel-fueled vehicles known in the
earth-moving, construction and agricultural industries such as, but
not limited to, scrapers, loaders, graders, tractors, and dump
trucks. The vehicle 10 may include a hood 12 for housing a clean
emissions module (CEM) 14 (FIG. 2) and an engine (not shown). The
hood 12 may include a removable panel 16 for access to the CEM 14.
The CEM 14 may include a selective catalytic reduction (SCR) module
18 and a diesel particulate filter (DPF) module 20 (both shown in
FIG. 2). The vehicle 10 may also include an insulated housing 22,
which may be coupled to a chassis 24 of the vehicle 10 proximate a
vehicle bumper 26. A frame 28 may extend from the chassis 24 to
further support the panel 16.
[0023] The insulated housing 22 may include a removable cover 30.
As best seen in FIG. 4 with the cover 30 removed, the insulated
housing 22 houses a diesel exhaust fluid (DEF) pump electronics and
tank unit (PETU) 32. The DEF PETU 32 may be coupled to the housing
22 and may include a DEF tank 34 and a pump and electronics unit
36, which may be coupled to the DEF tank 34. The DEF tank 34 may
include a neck 37 with a removable cap 38, which may be removed in
order to fill the DEF tank 34 with DEF.
[0024] With particular reference to FIGS. 5-6, the insulated
housing 22 may be formed of first and second side walls 40, 42, an
upper wall 44, a lower wall 46, an aft wall 48, and a fore wall 50
collectively defining a chamber 51. The first and second side walls
40, 42, the upper wall 44, and the fore wall 50 may be arranged to
form an access opening 52 into the chamber 51 of the insulated
housing 22. The insulated housing 22 may be disposed on the
diesel-fueled vehicle 10 such that the exterior of the aft wall 48
may face the CEM 14, as shown in FIG. 2. Referring back to FIGS.
5-6, a deflection flange 54 may extend outwardly from each of the
first and second side walls 40, 42, the upper wall 44, and the fore
wall 50 proximate the access opening 52. The removable cover 30 may
include a gasket seal 55 and may be removably coupled to the
deflection flange 54. In particular, the deflection flange 54 may
be contoured to complementarily receive a cover flange 56 of the
removable cover 30 (FIG. 1) such that the cover flange 56, which
may include the gasket seal 55, may be coupled in sealable fashion
to the deflection flange 54. The removable cover 30 may be coupled
to the deflection flange 54 with a plurality of fasteners 58 such
as, but not limited to, nut clips, nuts and bolts, or other
fasteners known in the industry. A lace trim 59 may be coupled
along the edges of the cover flange 56 and may extend from the
cover flange 56 such that it seats smoothly against the panel 16
and the vehicle bumper 26. The lace trim 59 may provide an
aesthetically appealing look as well as prevent dirt and debris
from collecting in a clearance gap between the deflection flange 54
and the panel 16.
[0025] The pump and electronics unit 36 may include a DEF line 60,
coolant lines 62, and wiring 64. The DEF line 60 may pass through
the aft wall 48 of the insulated housing 22 so that the pump and
electronics unit 36 of the DEF PETU 32 is in fluid communication
with the SCR module 18 of the CEM 14. The coolant lines 62 may pass
through the first side wall 40 of the insulated housing 22 so that
the pump and electronics unit 36 is in fluid communication with the
engine of the vehicle 10. Similarly, the wiring 64 may pass through
the upper wall 44 of the insulated housing 22 so that the pump and
electronics unit 36 is in electrical communication with the engine.
Although the DEF line 60, the coolant lines 62, and the wiring 64
have been described to pass through specific walls of the insulated
housing 22, it should be understood that the lines 60, 62 and the
wiring 64 may pass through any wall of the insulated housing 22.
Furthermore, each of the lines 60, 62 and the wiring 64 may be
sealed to the insulated housing 22 by one or more sealing gland
plates 66 to prevent air transfer through any of the apertures
disposed on the insulated housing 22 that the lines 60, 62 and the
wiring 64 pass through. In particular, the gland plates 66 prevent
high temperature air, which may be generated from the vehicle 10
components and has positive pressure, from leaking into the
insulated housing 22. The gland plates 66 may be disposed on the
interior and/or exterior of the insulated housing 22 while
surrounding the outer diameters of the lines 60, 62 and the wiring
64.
[0026] As best seen in FIGS. 5-7, a duct 68 may have one end
disposed on the first side wall 40 of the insulated housing 22 and
the other end coupled to a negative pressure source such as a
radiator fan shroud 70 surrounding a radiator fan 72 of the vehicle
10. The duct 68 may be sealed to the insulated housing 22 by one or
more duct sealing gaskets 73, which may be disposed on the interior
and/or exterior of the insulated housing 22. The duct 68 allows for
fluid communication between the chamber 51 of the insulated housing
22 and the radiator fan 72.
[0027] With particular reference to FIGS. 1 and 7, the cover 30 may
include a vent 74 and an aperture 76 for receiving the neck 37 of
the DEF tank 34. A positioning seal 78 may be disposed in the
aperture 76 to prevent air from flowing between the neck 37 and the
aperture 76. The vent 74 may be, as non-limiting examples, meshed
or grilled.
[0028] Referring back to FIG. 2, a bracket 80 may be coupled to the
exterior of the upper wall 44 of the insulated housing 22 in such a
manner to create a channel 82 between the bracket 80 and the
deflection flange 54. The channel 82 may receive the panel 16. The
bracket 80 may include bulb seals 84 for gap adjustment when the
panel 16 is inserted within the channel 82. The bracket 80 and bulb
seals 84 align and locate the panel 16 within the channel 82
relative to the insulated housing 22 and also retain the panel 16
to the insulated housing 22 in compliance with manufacturing,
assembly, and part-to-part movement tolerances.
[0029] As illustrated in FIG. 3, the insulated housing 22 may also
include an insulating blanket 86 such as, but not limited to, a
ceramic wool insulating blanket having a reflective exterior
surface and an alkaline silicate blanket. The insulating blanket 86
may surround the exterior of the insulated housing 22 to prevent
the insulated housing 22 from exposure to high temperatures. The
insulating blanket 86 may cover the first and second side walls 40,
42, the upper wall 44, and the aft wall 48 of the insulated housing
22.
[0030] An elastomeric mat 88, such as rubber or other resilient
material, as illustrated in FIG. 8, may be disposed between the
interior of the lower wall 46 of the insulated housing 22 and the
DEF tank 34 to cushion and minimize movement of the DEF tank
34.
[0031] FIG. 9 illustrates a flowchart 900 of a sample sequence of
steps which may be performed to insulate and cool a diesel exhaust
fluid (DEF) pump electronics and tank unit (PETU) from high
temperatures of a diesel-fueled vehicle. Box 910 shows the step of
providing an insulated housing to surround the DEF PETU and isolate
the DEF PETU from the high temperature. Another step, as
illustrated in box 912, may be providing a vent on a removable
cover of the insulated housing. As illustrated in box 914, another
step may be providing a duct on the insulated housing to allow
fluid communication between the insulated housing and a radiator
fan at a location wherein the radiator fan creates a negative
pressure that draws ambient air through the vent into the insulated
housing and through the duct. Another step may be providing an
insulating blanket around the insulated housing. Yet another step
may be providing a deflection flange on the insulated housing to
redirect a hot air flow away from the insulated housing. A further
step may be providing at least one gland plate to seal at least one
line to the insulated housing wherein the at least one line
provides communication between the DEF PETU and a vehicle
component.
[0032] While the present disclosure has shown and described details
of exemplary embodiments, it will be understood by one skilled in
the art that various changes in detail may be effected therein
without departing from the spirit and scope of the disclosure as
defined by claims supported by the written description and
drawings. Further, where these exemplary embodiments (and other
related derivations) are described with reference to a certain
number of elements it will be understood that other exemplary
embodiments may be practiced utilizing either less than or more
than the certain number of elements.
INDUSTRIAL APPLICABILITY
[0033] Based on the foregoing, it can be seen that the present
disclosure sets forth systems and methods for insulating and
protecting DEF PETU from high temperatures as well as inducing cool
ambient air to flow across the DEF PETU to further dissipate hot
air from the system and ensure the DEF PETU environment operates at
appropriate working temperatures.
[0034] During vehicle 10 operation, high temperatures are generated
underneath the hood 12 from various vehicle 10 components such as
the SCR module 18, the DPF module 20, the radiator fan 72, and the
engine. On account of the DEF PETU 32 being housed in the insulated
housing 22 with the cover 30 sealed thereto and the insulating
blanket 86 surrounding the insulated housing 22, the DEF PETU 32 is
insulated from such high temperatures. In particular, any
conductive heat from the chassis 24, convective heat from the
radiator fan 72, and radiant heat from the SCR module 18 and DPF
module 20 is prevented from transferring into the housing 22 and to
the DEF PETU 32 housed therein. The deflection flange 54 further
outwardly deflects any hot air leakage that may escape from under
the hood 12 due to a possible incomplete seal between the housing
22 and the panel 16 and thus may redirect the hot air leakage away
from the access opening 52. The insulating blanket 86, which may
surround the housing 22, further insulates the DEF PETU 32 from
exposure to the hot under hood air. Moreover, the sealing gland
plates 66 seal the DEF line 60, the coolant lines 62, and the
wiring 64 to the insulated housing 22 to seal and prevent hot air
leakage from the CEM 14 and vehicle 10 engine entering into the
insulated housing 22.
[0035] The duct 68 is coupled to the radiator fan shroud 70 at a
location where a negative pressure is created between the radiator
fan shroud 70 and the blades of the radiator fan 72. Consequently,
the negative pressure provides suction to the housing 22 such that
ambient air is drawn through the vent 74 into the housing 22 and
across the DEF PETU 32. The ambient air is then vacuumed through
the duct 68 and out to the radiator fan 72 so as to remove any heat
gains within the housing 22. The introduction of cool ambient air
into the housing 22 and removal of any hot air from the housing 22
provides an environment in which the DEF tank 34 and the pump and
electronics unit 36 operate at appropriate working
temperatures.
[0036] Moreover, the teachings of this disclosure may be employed
so that the DEF PETU 32 may be disposed in close proximity to the
CEM 14 and vehicle 10 engine, which is desired due to distance
requirements between the DEF PETU 32 and the CEM 14, space
availability on the vehicle 10, and access ability of the DEF PETU
32 for refilling, while also being isolated from the high
temperatures and further cooled to appropriate operating
temperatures. The ability to remove the removable cover 30 from the
insulated housing 22 provides accessibility to the DEF PETU 32 to
service and maintain components. Additionally, the access opening
52 of the insulated housing 22 may be sized so that the DEF PETU 32
may be installed as a complete assembly, which reduces vehicle
assembly time and labor costs. As the lace trim 59 of the removable
cover 30 may seat smoothly against the panel 16 and the vehicle
bumper 26, an aesthetically appealing look is provided as well as
assurance that dirt and debris are prevented from collecting
therebetween.
* * * * *