U.S. patent application number 11/857730 was filed with the patent office on 2009-03-19 for particle filter assembly.
This patent application is currently assigned to FEV MOTORENTECHNIK GMBH. Invention is credited to Marek Tatur, Dean Tomazic.
Application Number | 20090071123 11/857730 |
Document ID | / |
Family ID | 40453015 |
Filed Date | 2009-03-19 |
United States Patent
Application |
20090071123 |
Kind Code |
A1 |
Tomazic; Dean ; et
al. |
March 19, 2009 |
PARTICLE FILTER ASSEMBLY
Abstract
A particle filter assembly adapted to be mounted in an exhaust
gas stream of an internal combustion engine. The particle filter
assembly includes a wire mesh filter or sinter metal filter having
a mesh size sufficiently small to prevent the passage of
carbonaceous particles above a predetermined size through the mesh.
The filter is positioned in series with the exhaust gas stream from
the engine. A source of electrical power is electrically connected
to the filter to heat the filter to a temperature sufficient to
oxidize the carbonaceous material in the filter to carbon
dioxide.
Inventors: |
Tomazic; Dean; (Orion
Township, MI) ; Tatur; Marek; (Auburn Hills,
MI) |
Correspondence
Address: |
GIFFORD, KRASS, SPRINKLE,ANDERSON & CITKOWSKI, P.C
PO BOX 7021
TROY
MI
48007-7021
US
|
Assignee: |
FEV MOTORENTECHNIK GMBH
Aachen
DE
|
Family ID: |
40453015 |
Appl. No.: |
11/857730 |
Filed: |
September 19, 2007 |
Current U.S.
Class: |
60/274 ;
60/311 |
Current CPC
Class: |
F01N 3/027 20130101;
F01N 2570/10 20130101; F01N 9/002 20130101; Y02T 10/40 20130101;
Y02T 10/47 20130101; F01N 3/022 20130101 |
Class at
Publication: |
60/274 ;
60/311 |
International
Class: |
F01N 3/021 20060101
F01N003/021 |
Claims
1. A particle filter assembly adapted to be mounted in an exhaust
gas stream of an internal combustion engine comprising: an
electrically conductive filter having a mesh size sufficiently
small to prevent the passage of carbonaceous particles above a
predetermined size through the mesh, said filter being positioned
in series with the exhaust gas stream from the engine, a source of
electric power, a control circuit which electrically connects said
electric power source to said filter at spaced time intervals and
for a sufficient time during each connection of the electric power
to heat said filter to a temperature sufficient to oxidize the
carbonaceous material in at least a portion of the filter to carbon
dioxide.
2. The invention as defined in claim 1 wherein said filter
comprises stainless steel.
3. The invention as defined in claim 1 wherein said filter
comprises copper.
4. The invention as defined in claim 1 wherein said control circuit
sequentially electrically connects the electric power source to
different portions of the filter.
5. The invention as defined in claim 1 wherein said control circuit
is microprocessor based.
6. In combination with a vehicle having an internal combustion
engine with an exhaust gas stream, a particle filter assembly
comprising: a filter having a mesh size sufficiently small to
prevent the passage of carbonaceous particles above a predetermined
size through the filter, said filter being positioned in series
with the exhaust gas stream from the engine, a source of electric
power which includes an electric generator mechanically coupled to
a mechanical output from the internal combustion engine, said
electric power source being electrically connected to at least one
electrical system of the vehicle, a control circuit which
electrically connects said electrical power source to said filter
at spaced time intervals and for a sufficient time during each
connection of the electric power to heat said filter to a
temperature sufficient to oxidize the carbonaceous material in the
filter to carbon dioxide.
7. The invention as defined in claim 6 wherein said filter
comprises stainless steel.
8. The invention as defined in claim 6 wherein said filter
comprises copper.
9. The invention as defined in claim 6 wherein said control circuit
electrically connects said electric power source to said filter
whenever the electrical power output from said generator exceeds
the electrical power needs of said at least one electrical
system.
10. The invention as defined in claim 6 wherein said vehicle is a
train.
11. The invention as defined in claim 6 wherein said control
circuit electrically connects said electric power source to said
filter when the vehicle is in a boost status.
12. The invention as defined in claim 6 wherein said control
circuit sequentially electrically connects the electric power
source to different portions of the filter.
13. The invention as defined in claim 6 wherein said control
circuit is microprocessor based.
14. The invention as defined in claim 6 wherein a controller is
implemented having incorporated an estimation tool to decide
whether regeneration of said filter or parts of said filter will be
conducted or not based on an overall efficiency of the vehicle.
15. A method for regenerating a particle filter assembly mounted in
an exhaust gas stream of an internal combustion engine comprising
the steps of: positioning an electrically conductive filter having
a mesh size sufficiently small to prevent the passage of
carbonaceous particles above a predetermined size through the mesh
in series with the exhaust gas stream from the engine, electrically
connecting an electric power source to said filter at spaced time
intervals and for a sufficient time during each connection of the
electric power to heat said filter to a temperature sufficient to
oxidize at least a portion of the carbonaceous material in the
filter to carbon dioxide.
16. The method as defined in claim 15 and comprising the step of
sequentially electrically connecting the power source to different
portions of the filter.
17. The method as defined in claim 15 wherein the step of
sequentially electrically connecting the power source to different
portions of the filter comprises the step of sequentially
electrically connecting the power source to different portions of
the filter during different regeneration cycles.
Description
BACKGROUND OF THE INVENTION
[0001] I. Field of the Invention
[0002] The present invention relates to a particle filter assembly
adapted to be mounted in series with the exhaust gas stream from an
internal combustion engine.
[0003] II. Description of Related Art
[0004] In view of increasingly stringent governmental regulations,
off-road machinery, such as trains, marine vessels and machinery,
large mining vehicles and the like, need to be fitted with exhaust
treating devices to reduce the amount of pollutants exhausted to
the atmosphere. Such off-road devices are typically powered by
diesel engines which emit solid carbonaceous particles.
[0005] In such off-road vehicles, the internal combustion engine
has an output shaft mechanically connected to one or more electric
generators. The output from the electric generators, in turn, is
electrically connected to one or more electric engines which propel
the train.
[0006] In many operating conditions, such as when a train is
powered along a level path or an up slope, additional fuel may be
necessary for the internal combustion engine in order to provide
sufficient electrical output from the generators to power not only
the electric motors which propel the train, but also any other
electric systems in the train. Conversely, in other operating
conditions, such as a coast down condition when the train is
traveling along a down slope, the electrical generators on the
train generate excess electrical power that is, for the most part,
unused and therefore wasted. These conditions of excess electrical
power are known as the boost status for the train or other off-road
machinery.
SUMMARY OF THE PRESENT INVENTION
[0007] The present invention provides a particle filter for use
with the exhaust gas stream from an internal combustion engine
which utilizes the excess electrical energy generated during the
boost status of the machinery to clean or regenerate the particle
filter by oxidizing the carbonaceous particles contained within the
filter.
[0008] In brief, the particle filter assembly of the present
invention comprises a wire mesh filter or sinter metal filter
having a mesh size sufficiently small to prevent the passage of
carbonaceous particles above a predetermined size through the mesh.
The filter is positioned in series with the exhaust gas stream from
the internal combustion engine.
[0009] A source of electrical power which includes an electrical
generator is mechanically coupled with the mechanical output from
the internal combustion engine. Consequently, rotation of the
engine rotatably drives the generator to produce electric
power.
[0010] A control circuit electrically connects the electrical power
source to the filter at spaced time intervals during the boost
status for the vehicle and for a sufficient time during each
connection of electric power to the filter to heat the filter to a
temperature sufficient to oxidize the carbonaceous material in the
mesh to carbon dioxide. The harmless carbon dioxide is then
exhausted by the exhaust system to the atmosphere.
[0011] Consequently, the present invention effectively periodically
regenerates and cleans the filter in the exhaust gas stream from
the engine during boost status for the off-road machinery without
the necessity for the engine to produce excess electrical power to
do so. Rather, since only the excess electrical power during the
boost status of the engine is used to regenerate the filter, the
regeneration and cleaning of the filter is achieved in a highly
energy-efficient manner.
[0012] A method for regenerating or cleaning the filter is also
disclosed.
BRIEF DESCRIPTION OF THE DRAWING
[0013] A better understanding of the present invention will be had
upon reference to the following detailed description when read in
conjunction with the accompanying drawing, wherein like reference
characters refer to lice parts throughout the several views, and in
which:
[0014] FIG. 1 is a block diagrammatic view illustrating an
embodiment of the present invention; and
[0015] FIG. 2 is a plan view illustrating a portion of the
preferred embodiment of the present invention.
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE PRESENT
INVENTION
[0016] With reference first to FIG. 1, an off-road machine or
vehicle 10, such as a train engine car, marine application, large
mining vehicles and the like, is diagrammatically illustrated. The
vehicle 10 includes an internal combustion engine 12 that is
typically powered by diesel or other relatively low cost fuel. The
internal combustion engine 12 produces an exhaust gas stream
through an exhaust system 14 which includes one or more exhaust
pipes.
[0017] The internal combustion engine 12 includes an output shaft
16 which is rotatably driven by the internal combustion engine 12
during operation of the engine 12. The generator in the
conventional fashion generates electric power at its output 18.
[0018] The output 18 from the generator 20 is electrically
connected to one or more electric motors 22 which power the drive
system (not shown) for the vehicle 10. Consequently, when the load
increases and additional power is required by the electric motors
22 and/or other electric systems on the vehicle, additional fuel is
typically supplied to the engine 12 which increases the power
output from the engine 12. Conversely, under other operating
conditions, such as when the vehicle 10 is in a coast down
condition and traveling on a down slope and is in a boost status,
the vehicle electric motor 22 drives the generator 20 which then
produces excess electrical power. In the past this additional
electric power, for the most part, was unused and therefore
wasted.
[0019] With reference now to FIGS. 1 and 2, a particle filter
assembly 30 is positioned in series with the exhaust system 14 of
the internal combustion engine 12. Consequently, the exhaust gas
stream from the internal combustion engine 12 passes through the
filter assembly 30.
[0020] As best shown in FIG. 2, the particle filter assembly 30
includes a wire mesh or sinter metal filter 32 (hereinafter
collectively referred to as a filter) having a mesh size
sufficiently small to prevent the passage of carbonaceous particles
above a predetermined size through the wire mesh. Consequently, the
filter 32 entraps the carbonaceous particles in the smoke from the
internal combustion engine 12 that would otherwise be expelled to
the atmosphere.
[0021] The filter 32 may be constructed of any suitable material
that conducts electricity. For example, stainless steel, copper,
and other metals may be used to form the filter 32.
[0022] After a period of time of operation of the internal
combustion engine 12, the filter assembly 30 must be regenerated or
cleaned of the carbonaceous particles 34 in order to prevent
clogging of the filter assembly 30. Otherwise, such clogging would
impede the exhaust gas stream gas flow from the engine 12.
[0023] In order to regenerate or clean the filter assembly 30 at
spaced time intervals and preferably during boost status of the
vehicle 10, a control circuit 38, which may be microprocessor
based, is electrically connected between the generator output 18
and the wire mesh 32. During the boost status of the vehicle 10,
i.e. when the generator 20 generates excess electrical power, the
control circuit 38 electrically connects the output from the power
source to the filter 32 which, of course, causes heating of the
filter 32 due to the passage of electrical current and the
electrical resistance of the material forming the filter 32. The
control circuit 38, operating under either open loop or closed loop
control, controls the amount of electrical power supplied to the
mesh to heat the filter 32 to a temperature sufficient to oxidize
the carbonaceous material 34 in the filter 32 to carbon dioxide.
The carbon dioxide passes out through an outlet 40 (FIG. 1) from
the exhaust system 14 harmlessly into the atmosphere. Furthermore,
in doing so, the carbonaceous particles 34 are removed from the
filter 32 thus regenerating or cleaning the particle filter
assembly 30.
[0024] Although the control circuit 38 may completely regenerate
the wire mesh 32 during each regeneration cycle, alternatively the
control circuit 38, which may be microprocessor based, may only
partly regenerate the wire mesh 32 based on an estimation of
whether the regeneration would negatively influence the overall
efficiency of the operation of the wire mesh 32. Such an estimation
of the overall efficiency could, for example, utilize the exhaust
gas pressure across the wire mesh 32 and the effect on fuel
consumption to in turn control the degree of regeneration.
Additionally, the control circuit 38 may selectively electrically
energize different parts of the wire mesh 32 so that the different
parts of the wire mesh 32 may be sequentially regenerated during
different regeneration cycles.
[0025] Although the present invention has been described for use
with a train, it will be understood that the filter assembly 30 may
be used with other types of internal combustion engines without
deviation from the spirit or scope of the invention. Such other
types of internal combustion engines include, for example, marine
applications, large mining vehicles and the like.
[0026] A primary advantage of the present invention is that, since
the filter assembly 30 is regenerated or cleaned using only excess
electrical power which would otherwise be unused and thus wasted,
the present invention achieves cleaning of the filter assembly 30
without the consumption of extra fuel and thus is highly energy
efficient. However, the electrical power for the regeneration of
the filter 32 may alternatively be obtained, in whole or in part,
from batteries or other sources of electrical energy on the
vehicle.
[0027] The present invention also includes a method for
regenerating a particle filter assembly mounted in an exhaust gas
stream of an internal combustion engine comprising the steps of
positioning an electrically conductive filter having a mesh size
sufficiently small to prevent the passage of carbonaceous particles
above a predetermined size through the mesh in series with the
exhaust gas stream from the engine, and electrically connecting an
electric power source to said filter at spaced time intervals and
for a sufficient time during each connection of the electric power
to heat said filter to a temperature sufficient to oxidize at least
a portion of the carbonaceous material in the filter to carbon
dioxide. Optionally, the step of electrically connecting the
electric power source to the filter comprises the step of
sequentially electrically connecting the power source to different
portions of the filter during a single or sequential regeneration
cycles.
[0028] Optionally, a controller is implemented having incorporated
an estimation tool to decide whether regeneration of said filter or
parts of said filter will be conducted or not based on an overall
efficiency of the vehicle.
[0029] Having described our invention, many modifications thereto
will become apparent to those skilled in the art to which it
pertains without deviation from the spirit of the invention as
defined by the scope of the appended claims.
* * * * *