U.S. patent application number 11/993648 was filed with the patent office on 2010-04-01 for burner for regeneration of diesel engine particulate filter and diesel engine particulate filter having the same.
This patent application is currently assigned to KOREA INSTITUTE OF MACHINERY AND MATERIALS. Invention is credited to Sang Hyun Jeong, Seong Hun Sim.
Application Number | 20100077732 11/993648 |
Document ID | / |
Family ID | 37570672 |
Filed Date | 2010-04-01 |
United States Patent
Application |
20100077732 |
Kind Code |
A1 |
Jeong; Sang Hyun ; et
al. |
April 1, 2010 |
BURNER FOR REGENERATION OF DIESEL ENGINE PARTICULATE FILTER AND
DIESEL ENGINE PARTICULATE FILTER HAVING THE SAME
Abstract
Provided are a burner for regenerating a diesel particulate
filter and a diesel engine particulate filtering apparatus having
the same. The burner includes: an exhaust gas flow channel; a
swirler disposed between the exhaust gas flow channel and a
combustion chamber for swirling the exhaust gas; a carburetor for
gasifying a liquid fuel; a fuel injection nozzle for mixing the
gasified fuel from the carburetor with an air for burning, and
supplying the mixed gas made of the gasified fuel and the air to
the combustion chamber; a combustor disposed in the combustion
chamber for injecting the mixed gas supplied from the fuel
injection nozzle; an igniter for igniting the mixed gas injected
from the combustor by generating sparks; and a flame sensor for
sensing whether the flame is made on the combustor or not.
Inventors: |
Jeong; Sang Hyun; (Daejeon,
KR) ; Sim; Seong Hun; (Daejeon, KR) |
Correspondence
Address: |
RABIN & Berdo, PC
1101 14TH STREET, NW, SUITE 500
WASHINGTON
DC
20005
US
|
Assignee: |
KOREA INSTITUTE OF MACHINERY AND
MATERIALS
|
Family ID: |
37570672 |
Appl. No.: |
11/993648 |
Filed: |
June 21, 2006 |
PCT Filed: |
June 21, 2006 |
PCT NO: |
PCT/KR06/02395 |
371 Date: |
December 21, 2007 |
Current U.S.
Class: |
60/286 ;
60/303 |
Current CPC
Class: |
F01N 2240/14 20130101;
F01N 2240/20 20130101; F23D 2900/21003 20130101; F23D 91/02
20150701; F01N 2240/02 20130101; F01N 3/34 20130101; F01N 3/025
20130101; F23D 11/448 20130101; F01N 3/36 20130101 |
Class at
Publication: |
60/286 ;
60/303 |
International
Class: |
F01N 9/00 20060101
F01N009/00; F01N 3/10 20060101 F01N003/10 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 22, 2005 |
KR |
10-20050053958 |
May 26, 2006 |
KR |
10-2006-0047591 |
Claims
1. A burner for regenerating a diesel particulate filter,
comprising: an exhaust gas flow channel of a diesel engine, which
is disposed at the front of a combustion chamber on the same axis
of the combustion chamber; at least one of swirlers disposed
between the exhaust gas flow channel and the combustion chamber for
swirling the exhaust gas flowing into to the combustion chamber
through the exhaust gas flow channel; a carburetor including a
gasifying chamber for gasifying a liquid fuel, a fuel pump for
supplying the liquid fuel into the gasifying chamber, and a convey
air inflow path for supplying an air into the gasifying chamber to
convey the gasified fuel into a fuel injection nozzle; a fuel
injection nozzle for mixing the gasified fuel from the carburetor
with an air for burning, and supplying the mixed gas made of the
gasified fuel and the air to the combustion chamber; a combustor
disposed in the combustion chamber for injecting the mixed gas
supplied from the fuel injection nozzle; an igniter for igniting
the mixed gas injected from the combustor by generating sparks; and
a flame sensor for sensing whether the flame is made on the
combustor or not.
2. The burner of claim 1, wherein the fuel injection nozzle
includes: a mixing chamber for forming a mixed gas by mixing a
gasified fuel and an air for burning; a burning air inflow path
communicated with the mixing chamber for forming a passage to flow
the air for burning into the mixing chamber; a fuel inflow path
communicated with the gasifying chamber and the mixing chamber for
forming a passage to flow a gasified fuel from the gasifying
chamber to the mixing chamber; and a mixed gas inflow path
communicated with the mixing chamber and the combustion chamber for
forming a passage to flow the mixed gas from the mixing chamber to
the combustion chamber.
3. The burner of claim 2, wherein the mixed gas made of the
gasified fuel from the gasifying chamber and the air for conveying
from the convey air inflow path flows into the combustion chamber
through the mixed gas inflow path of the fuel injection nozzle, and
other air is not flew through the fuel injection nozzle.
4. The burner of claim 2, wherein the fuel injection nozzle is one
of a ventury type, an expanding type, and a swirling type.
5. The burner of claim 2, further comprising a supplementary air
inflow path com-municated with the exhaust gas flow channel of the
diesel engine for supplementary supplying an air to the exhaust gas
flow channel.
6. The burner of claim 1, further comprising a control unit for
electrically feedback controlling: a temperature and a pressure in
at least one of spots in the combustion chamber; a temperature and
a pressure of an air for conveying and an amount of flowing the air
for burning which flows into the gasifying chamber; a temperature
and a pressure of an air for burning and an amount of flowing the
air for burning which flows into the fuel injection nozzle; an
amount of liquid fuel supplied from a fuel tank using a fuel pump;
and operations of the combustor, the igniter, the flame sensor, and
the fuel supply pump.
7. The burner of claim 6, further comprising a temperature and
pressure sensor for sensing the temperature and pressure of the air
for conveying and transfers the sensed temperature and pressure to
the control unit, wherein the temperature and pressure sensor
includes a convey air controlling valve for controlling an amount
of flowing the air for conveying, which flows through the convey
air inflow path.
8. The burner of claim 6, further comprising a temperature and
pressure sensor for sensing the temperature and pressure of the air
for burning and transfers the sensed temperature and pressure to
the control unit, wherein the temperature and pressure sensor
includes a burning air controlling valve for controlling an amount
of flowing the air for burning, which flows through the burning air
inflow path.
9. The burner of claim 6, further comprising: a clean air inlet for
the igniter, which is communicated with the outside for sustaining
an igniting member of the igniter to be clean; and an electric
valve for controlling an amount of a fresh external air flowing
through the clean air inlet or the igniter in response to the
control unit.
10. The burner of claim 6, further comprising: a clean air inlet
for the flame sensor, which is communicated with the outside for
sustaining a sensing member of the flame sensor to be clean; and an
electric valve for controlling an amount of a fresh external air
flowing through the clean air inlet for the flame sensor in
response to the control unit.
11. The burner of claim 6, further comprising: a clean air inlet
for the flame sensor, which is communicated with the outside for
sustaining a sensing member of the flame sensor to be clean; and an
electric valve for controlling an amount of a fresh external air
flowing through the clean air inlet for the flame sensor in
response to the control unit.
12. The burner of claim 1, wherein the porous material of the
combustor is one of heat-resistant porous materials including a met
type metal fiber, a ceramic, and a foam metal.
13. The burner of claim 12, wherein the combustor has one of a
cylinder shape, a cone shape, a rectangle pipe shape and a disk
shape, and has a volume and a surface area, which is formed of an
inside where the mixed gas inflows and an outside where the mixed
gas is injected through.
14. The burner of claim 1, wherein the combustor further includes a
porous supporting member coupled to the inner side of the porous
material for holding the shape of the porous material.
15. The burner of claim 1, further comprising at least one layer of
a porous cylinder shaped flame holder disposed to surround the
external circumference of the combustor.
16. The burner of claim 1, further comprising a combustion chamber
where a mixed gas, which is made of an exhaust gas and a mixed gas
supplied from the fuel injection nozzle, is burned.
17. The burner of claim 16, wherein the inner wall of the
combustion chamber is lined with at least one of fireproof
insulators including asbestos, ceramicwool, cerakwool and
firebrick.
18. A diesel engine particulate filtering apparatus comprising: a
combustion chamber; an exhaust gas flow channel of a diesel engine,
which is disposed the front of the combustion chamber on the same
axis of the combustion chamber; at least one of swirlers disposed
between the exhaust gas flow channel and the combustion chamber for
swirling the exhaust gas flowing into to the combustion chamber
through the exhaust gas flow channel; a carburetor including a
gasifying chamber for gasifying a liquid fuel, a fuel pump for
supplying the liquid fuel into the gasifying chamber, and a convey
air inflow path for supplying an air into the gasifying chamber to
convey the gasified fuel into a fuel injection nozzle; a fuel
injection nozzle for mixing the gasified fuel from the carburetor
and an air for burning, and supplying the mixed gas made of the
gasified fuel and the air to the combustion chamber; a combustor
disposed in the combustion chamber for injecting the mixed gas
supplied from the fuel injection nozzle; an igniter for igniting
the mixed gas injected from the combustor by generating sparks; a
flame sensor for sensing whether the flame is made on the combustor
or not; and a diesel particulate filter disposed at one end of the
combustion chamber.
19. The diesel engine particulate filtering apparatus of claim 18,
further comprising an adaptor disposed at one end of the combustion
chamber and including a contracted portion at the center
thereof.
20. The diesel engine particulate filtering apparatus of claim 18,
further comprising a temperature uniformization unit disposed at
one end of the combustion chamber for accelerating mixing the high
temperature gas with the exhaust gas.
Description
TECHNICAL FIELD
[0001] The present invention relates to a diesel particulate filter
(DPF); and more particularly, to a burner for regenerating a diesel
particulate filter by oxidizing soot particles trapped in a diesel
particulate filter using heat in the diesel particulate filter for
reducing soot outputted from a diesel engine by filtering soot
particles included in an exhaust gas outputted from a diesel
engine, and a diesel particulate filtering apparatus having the
same.
BACKGROUND ART
[0002] Diesel engines have been generally equipped in trains,
vessels, and commercial vehicles. Also, diesel passenger vehicles
came out to the market, recently. Thus, the use of diesel engines
has increased.
[0003] As the use for diesel engines has increased, the large
amount of particulate matters (PM) such as soot and soluble organic
fraction (SOF) are produced from the diesel engines. Since such
particulate matters (PM) are major factors for environment
pollution, especially, air pollution. Therefore, the regulation of
diesel engines has become tightened.
[0004] In order to resolve the pollution problem of diesel engines,
a diesel particulate filter (DPF) was introduced. The DPF collects
soot outputted from a diesel vehicle in order to prevent soot
particles from being exhausted into the air. Also, there are many
researches in progress for developing the DPF.
[0005] FIG. 1 shows a conventional diesel particulate filter for
reducing soot produced from a diesel engine, which were introduced
in Korea Patent Publication No. 2003-0003599.
[0006] Referring to FIG. 1, the conventional diesel particulate
filter (DPF) includes a main body 10 having a monolith type ceramic
filter 11 for filtering soot particles in an exhaust gas outputted
from a diesel engine, and a burner 1 for generating the monolith
ceramic filter 11. The burner 1 includes a combustor 4 for
injecting mixed fuel supplied from a fuel injection pump 2 and an
air pump 3, and an ignition rod 5.
[0007] In the conventional DPF, soot particles included in the
exhaust gas outputted from the diesel engine are collected by the
monolith type ceramic filter 11. When the large amount of soot
particles is trapped in the ceramic filter 11, the pressure loss of
the ceramic filter 14 significantly increases. It greatly
influences the back pressure of a diesel engine. Therefore, the
soot particles collected in the filter must be removed regularly
from the filter 11 when a preset pressure is dropped.
Conventionally, the soot particles are removed from the filter 11
by increasing the temperature of exhaust gas to be higher than the
oxidation temperature of the soot, for example, higher than
600.degree. C., so as to oxidize (burn) the soot particles trapped
in the ceramic filter 11. In order to raise the temperature of the
exhaust gas to be higher than the oxidation temperature of the soot
particles, the flame of the burner 1 is used as a heat supplying
device. That is, a pressure sensor 6 may sense that an internal
pressure of the ceramic filter 11 increases after the large amount
of soot particles such as carbon is trapped in the filter. Then,
the pressure sensor 6 informs the controller 7 that the internal
pressure increases, and the controller 7 drives the burner 1 to
burn the soot particles in the filter 11. Then, the combustor 4
injects the fuel, and the ignition rod 5 ignites the fire on the
injected fuel. The combustor 4 raises the internal temperature of
the exhaust gas channel 20, while a flame holder 8 sustains the
flame made by the combustor 4. Therefore, the soot particles
collected at the ceramic filter 11 are burned and eliminated. Then,
the ceramic filter 11 can be newly used to collect the soot
particles outputted from the diesel engine.
[0008] As described above, the conventional liquid fuel injection
type burner lengthily forms the flame as shown in FIG. 1. It is
difficult to stably sustain the lengthily formed flame although the
flame holder 8 is included. Also, the stability of the flame is
greatly influenced by driving conditions of the engine. That is, it
is very difficult to stably sustain when the amount of following
the exhaust gas outputted from the engine and the pressure
conditions change abruptly. Thus, the flame uncontrollably shakes
in the exhaust gas, and is easily extinguished. These shortcomings
make the conventional DPF to become practical.
[0009] Especially, the amount of flowing the exhaust gas or the
pressure abruptly varies when the diesel engine accelerates or
decelerates. In this case, it is very difficult to increase or
sustain the temperature in the exhaust gas channel 20 because the
abrupt variation makes the flame instable and to be extinguished.
Accordingly, the regeneration of the filter through oxidizing the
soot particles trapped in the filter becomes difficult. That is,
the conventional burner may sustain the flame stably when the
diesel engine is regularly driven, for example, when the engine is
kept ticking over, when the engine is driven at a constant speed,
and when the engine stops. However, the conventional burner cannot
sustain the flame stably or often extinguishes the flame when the
driving conditions of the diesel engine abruptly change, for
example, when the diesel engine accelerates or decelerates. In this
case, the conventional burner cannot smoothly burn the soot
particles trapped in the filter 11. Therefore, the state of the
diesel particulate filter is getting deteriorated. Finally, the
filter 11 becomes incapable of filtering diesel particulate.
DISCLOSURE OF INVENTION
Technical Problem
[0010] It is, therefore, an object of the present invention to
provide a burner for generating a diesel particulate filter, which
is enhanced to constantly sustain a stable flame in the flow of
exhaust gas without being influenced by the abrupt variation of
driving conditions of the diesel engine, and a diesel engine
particulate filtering system having the same.
Technical Solution
[0011] In accordance with one aspect of the present invention,
there is a burner for regenerating a diesel particulate filter
including: an exhaust gas flow channel of a diesel engine, which is
disposed at the front of a combustion chamber on the same axis of
the combustion chamber; at least one of swirlers disposed between
the exhaust gas flow channel and the combustion chamber for
swirling the exhaust gas flowing into to the combustion chamber
through the exhaust gas flow channel; a carburetor including a
gasifying chamber for gasifying a liquid fuel, a fuel pump for
supplying the liquid fuel into the gasifying chamber, and a convey
air inflow path for supplying an air into the gasifying chamber to
convey the gasified fuel into a fuel injection nozzle; a fuel
injection nozzle for mixing the gasified fuel from the carburetor
with an air for burning, and supplying the mixed gas made of the
gasified fuel and the air to the combustion chamber; a combustor
disposed in the combustion chamber for injecting the mixed gas
supplied from the fuel injection nozzle; an igniter for igniting
the mixed gas injected from the combustor by generating sparks; and
a flame sensor for sensing whether the flame is made on the
combustor or not.
[0012] The fuel injection nozzle may include: a mixing chamber for
forming a mixed gas by mixing a gasified fuel and an air for
burning; a burning air inflow path communicated with the mixing
chamber for forming a passage to flow the air for burning into the
mixing chamber; a fuel inflow path communicated with the gasifying
chamber and the mixing chamber for forming a passage to flow a
gasified fuel from the gasifying chamber to the mixing chamber; and
a mixed gas inflow path communicated with the mixing chamber and
the combustion chamber for forming a passage to flow the mixed gas
from the mixing chamber to the combustion chamber.
[0013] The mixed gas made of the gasified fuel from the gasifying
chamber and the air for conveying from the convey air inflow path
may flow into the combustion chamber through the mixed gas inflow
path of the fuel injection nozzle, and other air is not flew
through the fuel injection nozzle.
[0014] The fuel injection nozzle may be one of a ventury type, an
expanding type, and a swirling type.
[0015] The burner may further include a supplementary air inflow
path communicated with the exhaust gas flow channel of the diesel
engine for supplementary supplying an air to the exhaust gas flow
channel.
[0016] The burner may further include a control unit for
electrically feedback controlling: a temperature and a pressure in
at least one of spots in the combustion chamber; a temperature and
a pressure of an air for conveying and an amount of flowing the air
for burning which flows into the gasifying chamber; a temperature
and a pressure of an air for burning and an amount of flowing the
air for burning which flows into the fuel injection nozzle; an
amount of liquid fuel supplied from a fuel tank using a fuel pump;
and operations of the combustor, the igniter, the flame sensor, and
the fuel supply pump.
[0017] The burner may further include a temperature and pressure
sensor for sensing the temperature and pressure of the air for
conveying and transfers the sensed temperature and pressure to the
control unit, wherein the temperature and pressure sensor includes
a convey air controlling valve for controlling an amount of flowing
the air for conveying, which flows through the convey air inflow
path.
[0018] The burner may further include a temperature and pressure
sensor for sensing the temperature and pressure of the air for
burning and transfers the sensed temperature and pressure to the
control unit, wherein the temperature and pressure sensor includes
a burning air controlling valve for controlling an amount of
flowing the air for burning, which flows through the burning air
inflow path.
[0019] The burner may further include: a clean air inlet for the
igniter, which is communicated with the outside for sustaining an
igniting member of the igniter to be clean; and an electric valve
for controlling an amount of a fresh external air flowing through
the clean air inlet or the igniter in response to the control
unit.
[0020] The burner may further include: a clean air inlet for the
flame sensor, which is communicated with the outside for sustaining
a sensing member of the flame sensor to be clean; and an electric
valve for controlling an amount of a fresh external air flowing
through the clean air inlet for the flame sensor in response to the
control unit.
[0021] The control unit may operate the burner if a pressure
difference sensed from the front end and the rear end of a diesel
particulate filter is greater than a predetermined threshold, and
the control unit stops the burner if a pressure difference sensed
from the front end and the rear end of the diesel particulate
filter is smaller than a predetermined threshold.
[0022] The porous material of the combustor may be one of
heat-resistant porous materials including a met type metal fiber, a
ceramic, and a foam metal.
[0023] The combustor may have one of a cylinder shape, a cone
shape, a rectangle pipe shape and a disk shape, and has a volume
and a surface area, which is formed of an inside where the mixed
gas inflows and an outside where the mixed gas is injected
through.
[0024] The combustor may further include a porous supporting member
coupled to the inner side of the porous material for holding the
shape of the porous material.
[0025] The burner may further include at least one layer of a
porous cylinder shaped flame holder disposed to surround the
external circumference of the combustor.
[0026] The burner may further include a combustion chamber where a
mixed gas, which is made of an exhaust gas and a mixed gas supplied
from the fuel injection nozzle, is burned.
[0027] The inner wall of the combustion chamber may be lined with
at least one of fireproof insulators including asbestos,
ceramicwool, cerakwool and firebrick.
[0028] In accordance with another aspect of the present invention,
there is provided a diesel engine particulate filtering apparatus
including: a combustion chamber; an exhaust gas flow channel of a
diesel engine, which is disposed the front of the combustion
chamber on the same axis of the combustion chamber; at least one of
swirlers disposed between the exhaust gas flow channel and the
combustion chamber for swirling the exhaust gas flowing into to the
combustion chamber through the exhaust gas flow channel; a
carburetor including a gasifying chamber for gasifying a liquid
fuel, a fuel pump for supplying the liquid fuel into the gasifying
chamber, and a convey air inflow path for supplying an air into the
gasifying chamber to convey the gasified fuel into a fuel injection
nozzle; a fuel injection nozzle for mixing the gasified fuel from
the carburetor and an air for burning, and supplying the mixed gas
made of the gasified fuel and the air to the combustion chamber; a
combustor disposed in the combustion chamber for injecting the
mixed gas supplied from the fuel injection nozzle; an igniter for
igniting the mixed gas injected from the combustor by generating
sparks; a flame sensor for sensing whether the flame is made on the
combustor or not; and a diesel particulate filter disposed at one
end of the combustion chamber.
[0029] The diesel engine particulate filtering apparatus may
further include an adaptor disposed at one end of the combustion
chamber and including a contracted portion at the center
thereof.
[0030] The diesel engine particulate filtering apparatus may
further include a temperature uniformization unit disposed at one
end of the combustion chamber for accelerating mixing the high
temperature gas with the exhaust gas.
ADVANTAGEOUS EFFECTS
[0031] A burner for regenerating a diesel particulate filter and a
diesel engine particulate filtering apparatus having the same
according to the present invention have following advantages.
[0032] At first, the burner according to the present invention
swirls an exhaust gas flowing into a combustion chamber by
disposing a swirler between the combustion chamber and a diesel
engine exhaust gas channel. Therefore, the stability of flame in a
combustion chamber can be improved, and the size of the burner for
regenerating the diesel particulate filter can be reduced.
[0033] Secondly, the burner according to the present invention can
instantly ignite and extinguish a flame on a porous mat type
combustor. Also, the burner can ignite, extinguish and stably
sustain the flame when the amounts of flowing the exhaust gas and
the pressure thereof abruptly change due to the abrupt variation of
the load of the diesel engine.
[0034] Thirdly, since the burner according to the present invention
includes the combustor having a comparatively larger surface by
forming the combustor made of porous mat type material in a cone
shape, a cylinder shape and a rectangle pipe shape, the heat can be
transferred quickly from the flames to the exhaust gas, and the
constant temperature is uniformly sustained in the combustion
chamber.
[0035] Fourthly, the inside wall of the combustion chamber is lined
with heat resistant material such as ceramic and firebrick to
insulate and to accumulate heat at the same time, and the
insulating material can be sustained to be clean because the soot
particles on the insulating material are oxidized by the
accumulated heat.
[0036] Fifthly, the burner according to the present invention can
be used to regenerate a particulate filter in diesel engines which
are equipped in trains, vessels and vehicles. The applicability of
the burner according to the present invention is very wide as other
purposes of the burner. It is very valuable in a view of the
environmental population.
[0037] Finally, the burner according to the present invention
includes an adaptor having a contracted portion at the center
thereof between the combustion chamber and the diesel particulate
filter so as to supply the exhaust gas with uniformly distributed
temperature. Therefore, the burner can minimize transforming the
diesel particulate filter when oxidizing the soot particles trapped
in the diesel particulate filter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0038] The above and other objects and features of the present
invention will become apparent from the following description of
the preferred embodiments given in conjunction with the
accompanying drawings, in which:
[0039] FIG. 1 is a diagram showing a conventional diesel
particulate filter;
[0040] FIG. 2 is a diagram illustrating a diesel engine particulate
filtering apparatus having a burner for regenerating a diesel
particulate filter according to an embodiment of the present
invention;
[0041] FIG. 3 is a diagram illustrating a burner for regenerating a
diesel particulate filter shown in FIG. 2 according to an
embodiment of the present invention;
[0042] FIG. 4 is a perspective view illustrating a swirler shown in
FIG. 3;
[0043] FIG. 5 is a diagram illustrating a burner for regenerating a
diesel particulate filter according to another embodiment of the
present invention;
[0044] FIGS. 6 and 7 are cross-sectional views of a fuel injecting
nozzle shown in FIG. 3 according to an embodiment of the present
invention;
[0045] FIGS. 8 and 9 are cross-sectional views of a fuel injecting
nozzle shown in FIG. 3 according to another embodiment of the
present invention;
[0046] FIGS. 10 and 11 cross-sectional views of a combustor shown
in FIG. 3 according to another embodiment of the present
invention;
[0047] FIG. 12 is a cross-sectional view of a flame holder in a
burner for regenerating a diesel particulate filter shown in FIG.
3;
[0048] FIGS. 13 and 14 are cross-sectional views of a burner for
regenerating a diesel particulate filter having an adapter in a
combustion chamber;
[0049] FIGS. 15 and 16 show a temperature uniformization unit shown
in FIG. 2;
[0050] FIG. 17 is a partial cross-sectional view of a combustion
chamber with a temperature uniformization unit in the diesel engine
particulate filtering apparatus shown in FIG. 2;
[0051] FIGS. 18 and 19 show a burner for regenerating a diesel
particulate filter having an adaptor and a temperature
uniformization unit according to an embodiment of the present
invention; and
[0052] FIG. 20 shows a diesel engine particulate filtering
apparatus which is feed-back controlled by a control unit according
to an embodiment of the present invention.
BEST MODE FOR CARRYING OUT THE INVENTION
[0053] Other objects and aspects of the invention will become
apparent from the following description of the embodiments with
reference to the accompanying drawings, which is set forth
hereinafter.
[0054] FIG. 2 is a diagram illustrating a diesel engine particulate
filtering apparatus having a burner for regenerating a diesel
particulate filter according to an embodiment of the present
invention, and FIG. 3 shows a burner for regenerating a diesel
particulate filter, which is shown in FIG. 2. FIG. 4 is a
perspective view illustrating a swirler shown in FIG. 3.
[0055] FIG. 5 is a diagram illustrating a burner for regenerating a
diesel particulate filter according to another embodiment of the
present invention, FIG. 6 and FIG. 7 are cross-sectional views of a
fuel injecting nozzle according to an embodiment of the present
invention, and FIGS. 8 and 9 are cross-sectional views of a fuel
injecting nozzle according to another embodiment of the present
invention. FIGS. 10 and 11 are cross-sectional views of a combustor
according to another embodiment of the present invention.
[0056] FIG. 12 is a cross-sectional view of a flame holder in a
burner for regenerating a diesel particulate filter shown in FIG.
3, FIGS. 13 and 14 are cross-sectional views of a burner for
regenerating a diesel particulate filter having an adapter in a
combustion chamber, and FIGS. 15 and 16 show a temperature
uniformization unit shown in FIG. 2. FIG. 17 is a partial
cross-sectional view of a combustion chamber with a temperature
uniformization unit in the diesel engine particulate filtering
apparatus shown in FIG. 2.
[0057] FIGS. 18 and 19 show a burner for regenerating a diesel
particulate filter having an adaptor and a temperature
uniformization unit according to an embodiment of the present
invention, and FIG. 20 shows a diesel engine particulate filtering
apparatus, which is feedback controlled by a control unit according
to an embodiment of the present invention.
[0058] Referring to FIG. 3, the burner 100 for regenerating a
diesel particular filter according to the present embodiment
includes an exhaust gas channel 300 disposed at the front of a
combustion chamber 110 on the same axis of the combustion chamber
110 for flowing an exhaust gas into the combustion chamber 110, a
carburetor 120 for gasifying liquid fuel such as diesel, a fuel
injection nozzle 130 for mixing the gasified fuel and an air for
burning and supplying the mixed gas to the combustion chamber 110,
a combustor 140 for forming a flame by injecting the mixed gas
supplied from the fuel injection nozzle 130, an igniter 150 for
igniting the mixed gas injected from the combustor 140 so as to
form the flame on the combustor 140, and a flame sensor 160 for
sensing whether a flame is made on the combustor 140 or not.
[0059] Also, the burner 100 further includes a swirler 200 disposed
between the exhaust gas channel 300 and the combustion chamber
110.
[0060] As shown in FIG. 4, the swirler 200 forms a swirling gas
flow in the length direction of the combustion chamber 110.
[0061] The swirling gas flow guides the exhaust gas outputted from
a diesel engine to be swirled while flowing from the exhaust gas
channel 300 into the combustion chamber 110. Therefore, the exhaust
gas flows into the combustion chamber 110 with the exhaust gas
being rotated about the central axis of the combustion chamber
110.
[0062] Referring to FIG. 3 again, the carburetor 120 includes a
gasifying chamber 121 for gasifying a liquid fuel supplied from a
fuel tank 123 by the pumping operation of a liquid pump 122.
[0063] In the gasifying chamber 121, the gasified fuel is mixed
with an air so as to form a first mixed gas. The first mixed gas is
conveyed to a mixing chamber 131 of the fuel injection nozzle 130
by the air from a convey air inflow path 124.
[0064] The gasifying chamber 121 may include a gasifying unit for
supplying heat to gasify a liquid fuel. As the gasifying unit,
various units capable of gasifying the liquid fuel including a
heater may be used.
[0065] In addition, the carburetor 120 may include an atomizer for
atomizing the liquid fuel into fine liquid drops in order to
accelerate gasifying the liquid fuel. For example, an ultrasonic
atomizer may be used as the atomizer.
[0066] Meanwhile, the fuel injection nozzle 130 includes a mixing
chamber 131 for forming a mixed gas by mixing the first mixed gas,
which is provided from the gasifying unit 120, with an air for
burning.
[0067] The air for burning is supplied from a burning air inflow
path 133 that is communicated with the outside and the mixing
chamber 131. The first mix gas is supplied from a first mixed gas
inflow path 125 which is communicated with the gasifying unit 121
and the mixing chamber 131.
[0068] Also, the fuel injection nozzle 130 further includes a fuel
injection nozzle inlet 136 interposed between the burning air
inflow path 133 and the mixing chamber 131, and a mixed gas inflow
path 132 for flowing the mixed gas from the mixing chamber 131 to
the combustion chamber 110.
[0069] Meanwhile, the normal temperature air may be supplied from
the burning air inflow path 133 and the convey air inflow path 124.
However, a heating unit may be disposed at the burning air inflow
path 133 and the convey air inflow path 124 to heat the air for
conveying and burning to have a predetermined temperature.
[0070] The heating unit may be directly disposed at the burning air
inflow path 133 and the convey air inflow path 124 to heat the air
flowing through the inflow paths 124 and 133. Also, the heating
unit may be separately disposed from the burning air inflow path
133 and the convey air inflow path 124. In this case, the heating
unit heats the air to have a predetermined temperature and runs the
heated air into the inflow paths 124 and 133. That is, the heating
unit may be embodied as various forms.
[0071] For example, the air for burning and conveying may be heated
using the heat of the exhaust gas outputted from the diesel engine
by disposing the burning air inflow path 133 and the convey air
inflow path 124 to pass the flow of exhaust gas outputted from the
diesel engine.
[0072] For another example, the air may be heated by letting the
high temperature gas outputted from the combustion chamber flow
around the burning air inflow path 133 and the convey air inflow
path 124, or by disposing the burning air inflow path 133 and the
convey air inflow path 124 to pass the combustion chamber to heat
the air flowing the inflow paths 133 and 124 using the high
temperature gas in the combustion chamber.
[0073] Meanwhile, the burner 100 according to the present
embodiment may be shown to supply the air for burning only through
the burning air inflow path 133. However, the present invention is
not limited thereby. The burner 100 according to the present
invention may not include the burning air inflow path 133 as shown
in FIG. 5.
[0074] If the burning air inflow path 133 is not included, the
first mixed gas created from the carburetor 120 flows into the fuel
injection nozzle 130 through a first mixed gas inflow path 125
which is communicated with the fuel injection nozzle inlet 136.
[0075] The first mixed gas flows into the combustor 140 from the
fuel injection nozzle 130, and the first mixed gas is injected
through the combustor 140. Then, the igniter 150 ignites the first
mixed gas injected from the combustor 140.
[0076] If the air for burning is insufficient to burn the first
mixed gas, the oxygen included in the exhaust gas flew into the
combustion chamber 110 may be used as the air for burning the first
mixed gas.
[0077] Meanwhile, the burner 100 may further include a
supplementary burning air inflow path which is communicated with
the exhaust gas channel 300 to sufficiently supply the air if the
amount of oxygen included in the exhaust gas is smaller than the
required amount of oxygen.
[0078] The fuel injection nozzle 130, as shown in FIG. 6, may have
a ventury shape that has a cross-section gradually reduced along
the flow of the mixed gas.
[0079] Due to the ventury shape, the mixing chamber 131 of the fuel
injection nozzle 130 has comparatively lower pressure than the
gasifying chamber 121. Therefore, the first mixed gas is inhaled
from the gasifying chamber 121 to the mixing chamber 131. That is,
the first mixed gas smoothly flows into the combustion chamber
110.
[0080] Also, the fuel injection nozzle 130, as shown in FIGS. 7 to
9, may have the identical cross-section compared to the burning air
inflow path 133, or have an expanding type cross section which
gradually expanded toward the mixing chamber 131. Furthermore, the
fuel injection nozzle 130 may include swirlers 134a and 134b
disposed in one end of the expanding type cross section or the
center portion thereof.
[0081] The combustor 140, as shown in FIG. 3, is made of one of
high heat resistant porous material such as mat type metal fiber,
ceramic or foam metal.
[0082] Since the combustor 140 is formed of the porous material
which functions as a plurality of fine flame holes, a plurality of
very short flames are formed at the same time. Accordingly, the
accumulated heat formed on the combustor 140 prevents the flames
from being easily extinguished and enables to make flames on the
entire surface of the combustor 140 in a very short time.
[0083] The combustor 140, as shown in FIG. 3, may be formed in not
only a cone shape, but also a cylinder shape 140a, a rectangular
pipe shape 140b and a disk shape as shown in FIGS. 10 and 11.
[0084] As shown in FIG. 3, the combustor 140 may further include a
porous supporting member 141 coupled to the inside of the porous
material.
[0085] If the combustor 140 is made of material that cannot hold
its shape, the supporting member 141 formed in the corresponding
shape of the combustor 140 is disposed inside the combustor 140 to
support the combustor 140 to hold its shape.
[0086] The igniter 150 ignites the mixed gas injected from the
combustor 140 by generating sparks. A heating unit that locally
generates a high temperature in a close distance from the combustor
may be used as the igniter 150.
[0087] For example, when a power supply 151 supplies high voltage
to the igniter 150, the igniter 150 generates electric discharging
to ignite the mixed gas injected from the combustor 140 so as to
form flames on the combustor 140. The igniter 150 may include a
spark igniter using high voltage discharging, a rod type electric
heater and other heating units.
[0088] Since the igniter 150 functions to generate sparks on the
mixed gas injected from the combustor, the igniter 150 may be
polluted by soot particles in the exhaust gas. Therefore, the
performance of the igniter 150 may be degraded.
[0089] Therefore, an igniting member 152 of the igniter 150 must be
kept clean. In order to keep the igniting member 152 clean, the
igniter 150 may further include a clean air inlet 153 communicated
with the igniter 153.
[0090] The flame sensor 160 senses whether the flame is made on the
combustor 140 or not. When the flame sensor 160 senses that the
flame is made on the combustor 140, the flame sensor 160 stops the
igniter 150.
[0091] Therefore, a flame sensing member 161 of the flame sensor
160 must be kept clean. In order to keep the flame sensing member
160 clean, the flame sensing member 161 may further include a clean
air inlet 162 communicated with the outside.
[0092] As shown in FIG. 12, at lest one layer of a cylinder type
porous flame holder 111 may be disposed to surround the external
circumference of the combustor 140. Such a flame holder 110
protects the flames.
[0093] Also, the burner 100 according to the present embodiment may
further include a combustion chamber 110. In the combustion chamber
110, the combustor 140 is disposed and provides a space for the
combustor 140 to form flames.
[0094] The inner wall of the combustion chamber 110 may be lined
with a fireproof insulator 113 such as asbestos, ceramic wool,
creak wool or firebrick.
[0095] The fireproof insulator 113 accumulates the heat inside the
combustion chamber 110 by thermally insulating the inner wall of
the combustion chamber 110. The accumulated heat oxidizes the soot
particles attached on the fireproof insulator 113 to keep the
thermal insulator 113 clean.
[0096] Referring to FIG. 2, a diesel engine particulate filtering
apparatus 1000 according to the present invention includes the
burner 100 for regenerating a diesel particulate filter 400, a
diesel particulate filter 400, a control unit 170 for electrically
controlling the burner 100, a revolution rate sensor 810, a
temperature sensor 820 and a pressure sensor 830 for sensing the
revolution rate of the engine, the temperature and the pressure of
the exhaust gas produced from the engine.
[0097] The diesel engine particulate filtering apparatus 1000 may
receive signals related to information about an engine revolution
rate, an engine load, the temperature, and the pressure of an
exhaust gas from an engine electric control device 900 disposed in
a vehicle through the control unit 170.
[0098] The diesel engine particulate filtering apparatus 1000 may
further include a diesel particulate filter 400 at one end of the
combustion chamber of the burner 100.
[0099] Also, as shown in FIGS. 13 and 14, the diesel engine
particulate filtering apparatus 100 may further include an adaptor
700a or 700b interposed between the combustion chamber 110 and the
diesel particulate filter 400.
[0100] The adaptor 700a is disposed between the combustion chamber
110 and the diesel particulate filter 400, and includes a
contracted channel and an expanded channel. On the contrary, the
adaptor 700b is disposed at one end of the combustion chamber 100,
and the adaptor 700b has a shape in which the diameter thereof is
getting narrowed from the one end of the combustion chamber
100.
[0101] The contracted channel of the adaptor 700a or 700b makes an
exhaust gas in the combustion chamber and a high temperature
combustion gas generated from the flame of the combustor to be
smoothly mixed. After passing the contracted channel, the exhaust
gas has uniform temperature distribution in the cross section of
the channel.
[0102] Also, the temperature difference of the diesel particulate
filter 400 is minimized by letting the exhaust gas flows into the
diesel particulate filter 400 with uniform temperature
distribution. Also, the uniform temperature distribution prevents
the unbalanced oxidization while oxidizing the soot particles
trapped in the diesel particulate filter 400. Furthermore, the
uniform temperature distribution prevents the diesel particulate
filter 400 from being physically transformed if the diesel
particulate filter is made of material that can be easily
transformed by heat.
[0103] The diesel engine particulate filtering apparatus 1000 may
further include a temperature uniformization unit 600 as shown in
FIGS. 15 and 16.
[0104] The temperature uniformization unit 600 accelerates mixing
an exhaust gas from the combustion chamber 110 and a high
temperature combustion gas generated from the flames of the
combustor 130.
[0105] Referring to FIG. 17, the temperature uniformization unit
600 is interposed between one end of the combustion chamber 110 and
the diesel particulate filter 400, and makes the exhaust gas
distributed in the combustion chamber 110 and the high temperature
combustion gas generated from the flames of the combustor 140 to be
mixed smoothly.
[0106] Therefore, by supplying the exhaust gas having uniform
temperature distribution in a vertical direction of the combustion
chamber in the cross section of the combustion chamber 110 to the
diesel particulate filter 400, the temperature difference in the
diesel particulate filter 400 is minimized, the unbalanced
oxidization of the soot particles trapped at the diesel particulate
filter 400 is prevented, and the diesel particulate filter 400 is
prevented from being physically transformed by heat. Furthermore,
the radiant heat of the temperature uniformization unit 600 heated
by the mixed gas can effectively increase the temperature of the
diesel particulate filter 400.
[0107] Herein, any units that can archive the described object and
affects through accelerating mixing the mixed gas may be used as
the temperature uniformization unit 600.
[0108] The temperature uniformization unit 600 and the adaptor 700a
or 700b may be independently used. As shown in FIGS. 18 and 19, at
least one of the temperature uniformization unit 600 and the
adaptor 700a or 700b are used together.
[0109] Meanwhile, a numeral reference 114 refers to a supporting
frame for firmly supporting the combustor 140, the igniter 150, the
flame sensor 160 and the flame holder 111, which are disposed in
the combustion chamber 110.
[0110] The diesel engine particulate filtering apparatus 1000
according to an embodiment of the present invention may be
eclectically feedback controlled by the control unit 170. In order
to clearly describe, symbols will be defined as follows.
[0111] PIF: a pressure in the front end of the diesel particulate
filter 400 when the diesel particulate filter 400 is in a clean
state, that is, when no soot particle is trapped in the diesel
particulate filter 400.
[0112] PIR: a pressure in the rear end of the diesel particulate
filter 400 when the diesel particulate filter 400 is in a clean
state, that is, when no soot particle is trapped in the diesel
particulate filter 400.
[0113] .DELTA.PI: a pressure difference between the front end and
the rear end of the diesel particulate filter 400 when the diesel
particulate filter is in a clean state. (.DELTA.PI=PIF-PIR)
[0114] .DELTA.PI: a pressure difference between the front end and
the rear end of the diesel particulate filter 400 after oxidizing
the soot particles trapped in the diesel particulate filter
400.
[0115] PRF: a pressure at the front end of the diesel particulate
filter 400 when the diesel particulate filter 400 is required to be
regenerated.
[0116] PRR: a pressure at the rear end of the diesel particulate
filter 400 when the diesel particulate filter 400 is required to be
regenerated.
[0117] .DELTA.PR: a pressure difference between the front end and
the rear end of the diesel particulate filter 400 when the diesel
particulate filter 400 is required to be regenerated.
[0118] P1: a pressure at the front end of the diesel particulate
filter 400 while the diesel particulate filter 400 is collecting
soot particles.
[0119] P2: a pressure at the rear end of the diesel particulate
filter 400 while the diesel particulate filter 400 is collecting
the soot particles.
[0120] .DELTA.P: a pressure difference between the front end and
the rear end of the diesel particulate filter 400 when regeneration
is required (.DELTA.P=P1 P2)
[0121] TIF: a temperature in the front end of the diesel
particulate filter 400 when the diesel particulate filter 400 is in
a clean state, that is, when no soot particle is trapped in the
diesel particulate filter 400.
[0122] TIR: a temperature in the rear end of the diesel particulate
filter 400 when the diesel particulate filter 400 is in a clean
state, that is, when no soot particle is trapped in the diesel
particulate filter 400.
[0123] .DELTA.TI: a temperature difference between the front end
and the rear end of the diesel particulate filter 400 when the
diesel particulate filter is in a clean state.
(.DELTA.TI=TIF-TIR)
[0124] TRF: a temperature at the front end of the diesel
particulate filter 400 when regeneration is required.
[0125] TRR: a temperature at the rear end of the diesel particulate
filter 400 when regeneration is required.
[0126] .DELTA.TR: a temperature difference between the front end
and the rear end of the diesel particulate filter 400 when
regeneration is required.
[0127] T1: a temperature at the front end of the diesel particulate
filter 400 while the diesel particulate filter 400 is collecting
soot particles.
[0128] T2: a temperature at the rear end of the diesel particulate
filter 400 while the diesel particulate filter 400 is collecting
the soot particles.
[0129] .DELTA.T: a temperature difference between the front end and
the rear end of the diesel particulate filter 400 when regeneration
is required (.DELTA.T=T1-T2)
[0130] TOX: an oxidization temperature of soot particles
[0131] TEN: a temperature of exhaust gas outputted from an
engine
[0132] PEN: a pressure of exhaust gas outputted from an engine
[0133] Hereinafter, the operations of the control unit 170 in the
diesel engine particulate filtering apparatus 1000 will be
described with reference to FIG. 20.
[0134] Referring to FIG. 20, the control unit 170 includes signal
transmission lines 196a, 196b, 196c, 196d, 850a, 850b, 910a, 910b,
910c, 910d and 910e for receiving and transmitting signals related
to a temperature and a pressure, a microprocessor for performing
various calculations, a memory for storing various data and a
display panel.
[0135] The control unit 170 sets and stores all initial values for
controlling .DELTA.PI, PIF, PIR, .DELTA.PR, PRF, PRR, TIF, TIR,
.DELTA.TI, TRF, TRR, .DELTA.TR, and the oxidization temperature of
the soot particulate. Also, a correcting value, a graph, and a data
map related to a engine load, an engine revolution rate, the amount
of flowing engine exhaust gas, a temperature, and a pressure of an
engine exhaust gas for driving the diesel engine particulate
filtering apparatus 100 are set by a related program in the control
unit 170. Furthermore, a correcting value, a graph and a data map
related to a relation between the opening/closing angle of the
electric valve and the driving conditions of the engine are set by
a predetermined program in the control unit 170 in order to
optimally control the opening level of the electric valves 181 and
182 according to the engine load, the engine revolution rate and
the amount of flowing the engine exhaust, which dynamically change,
through exchanging signals with the control unit 170. Herein, the
opening/closing angle denotes the optimal driving condition of the
burner 100.
[0136] The engine 800 includes a revolution rate sensor 810 for
transferring the revolution rate of the engine to the control unit
170.
[0137] When the engine 800 starts, the power is supplied to the
control unit 170 through a signal transmitted from an engine
control unit 900. Then, the state of the control unit 170 transits
into an operation preparing state, and a time display panel of the
control unit 170 begins to operate.
[0138] When the engine 800 starts, the power may be directly
supplied to the control unit 170 from a condenser. Then the state
of the control unit 170 transits into an operation preparing state,
and the time display panel such as a timer of the control unit 170
begins to operate.
[0139] After the engine starts, the control unit 170 receives
signals informing the engine starts and a revolution rate of the
engine sensed by the revolution rate sensor 810. The engine
revolution rate may be transmitted from the engine control unit 900
to the control unit 170 although the revolution rate sensor 810 is
not included.
[0140] Also, the signal transmission lines 910a, 910b, 910c, 910d
and 910e are disposed between the engine control unit 900 and the
control unit 170, and signals related to driving states of the
engine 800 are transmitted to the control unit 170 through the
signal lines 910a, 910b, 910c, 910d and 910e.
[0141] The engine exhaust gas produced from the engine 800 flows
into the burner 100 through an exhaust gas discharging channel 840
interposed between the exhaust gas discharging outlet of the engine
800 and the exhaust gas channel 300 of the burner 100. When the
engine starts, the temperature sensors 191a and 191b and the
pressure sensors 194a and 194b disposed at the front end and the
rear end of the diesel particulate filter 400 sense the temperature
and the pressure of at least one of spots in the diesel particulate
filter 400 and transmit the sensed signals to the control unit 170.
The control unit 170 calculates the temperature difference and
pressure difference between the front end and the read end of the
filter 140 based on the sensed signals.
[0142] The signals related to the calculated temperature difference
and pressure difference are transferred from the control unit 170
to the engine control unit 900 through the signal transmission
lines 930a, 930b and 930c. It is preferable to display the
calculated temperature difference and pressure difference through a
display panel 950 by transferring the signals to the display panel
950.
[0143] The soot particles in the diesel engine exhaust gas, which
flow into the combustion chamber 110 after passing the swirler 200
through the exhaust gas channel 300, are trapped at the diesel
particulate filter 400 while passing the diesel particulate filter
400.
[0144] When the diesel engine exhaust gas passes the diesel
particulate filter 400, the temperature sensors 191a and 191b and
the pressure sensors 194a and 194b measure the temperature and the
pressure of the front end and the read end of the diesel
particulate filter 400, and transfer the measured temperature and
pressure to the control unit 170.
[0145] The control unit 170 receives the temperature and the
pressure of the front end and the read end of the diesel
particulate filter 400 and calculates the difference between the
temperatures and the pressures at the front end and the rear end of
the diesel particulate filter 400. Then, the control unit 170
compares the calculated differences with a preset pressure
difference (.DELTA.PR) that denotes a pressure different requiring
the diesel particulate filter 400 to be regenerated, which is
pre-stored in the control unit 170. If the calculate pressure
difference is smaller than the preset pressure difference
(.DELTA.PR), the control unit 170 does not transfer any signal to
turn on the burner 100 for regenerating a diesel particulate filter
400.
[0146] Calculating the pressure difference and comparing the
calculated pressure difference with the preset pressure difference
is continuously performed at a regular interval. A time of
performing the calculating and comparing operation and the
calculated pressure difference are stored in a memory of the
control unit 170 with the engine revolution rate, the engine load,
and the amount of flowing the exhaust gas outputted from the engine
900. That is, it functions as a black box.
[0147] As the engine 800 is continuously driving, the diesel engine
exhaust gas constantly flows into the combustion chamber 110, and
the amount of soot particles trapped in the diesel particulate
filter 400 gradually increases. The temperature sensors 191a and
191b and the pressure sensors 194a and 194b continuously transmit
the temperature and pressure data to the control unit 170. The
control unit 170 calculates the temperature difference and the
pressure difference (.DELTA.P) at the front end and the read end of
the diesel particulate filter 400. Then, the control unit 170
compares the calculated pressure difference with the preset
pressure difference (.DELTA.PR) and stores the time, the
temperature, the pressure, the temperature difference, the pressure
difference, the engine revolution rate, the engine load and the
amount of flowing the exhaust gas. These operations are repeatedly
performed while the engine 800 is driving.
[0148] Since the diesel particulate filter 400 is not required to
be regenerated when the calculated pressure difference (.DELTA.P)
is smaller than the preset pressure difference (.DELTA.PR) while
repeatedly performing the operations, the control unit 170 does not
transmit any signal to the burner 100 to turn on the burner 100 for
regenerating the diesel particulate filter.
[0149] However, if the calculated pressure difference (.DELTA.P) is
greater than the preset pressure difference (.DELTA.PR), the
control unit 170 transmits signals as follows in order to drive the
burner 100 for regenerating a diesel particulate filter.
[0150] At first, the control unit 107 calculates the amount of
flowing the exhaust gas and the pressure based on the engine
revolution rate and the engine load, which are transmitted from the
engine 800 to the control unit 170. Then, the control unit 107
feedback controls an electric valve 182 according to the calculated
amount of flowing exhaust gas and pressure by transferring control
signals to the electric valve 182 disposed at the convey air inflow
path 124. The control unit 107 opens the electric valve 182 as much
as the optimal air supplying state in order to supply the
appropriate amount of air to the carburetor 120.
[0151] Then, the control unit 170 drives the igniter 150 by
transmitting a control signal to the igniter 150, and the control
unit 170 transmits an operation start signal to the fuel pump 122
through electric feedback control in order to supply the
appropriate amount of fuel to the carburetor 120 for the calculated
amount of exhaust gas and pressure.
[0152] Then, the first mixed gas outputted from the carburetor 120
through the first mixed gas inflow path 125 is injected to the
combustion chamber 110 through the combustor 140 after injected
into the fuel injection nozzle 130.
[0153] Then, the igniter 150 forms flames on the combustor 140, and
the flame sensor 160 transmits a flame detecting signal to the
control unit 170. The control unit 170 stores data related to the
time of igniting, the driving condition of the engine, the
temperature and pressure of the front end and the read end of the
diesel particulate filter 400 at the memory.
[0154] When the control unit 170 receives the flame detecting
signal from the flame sensor 160, the control unit 170 transmits an
operation stop signal to an igniter driving unit 151 to stop the
igniter 150. Also, the control unit 170 transmits a signal to the
electric valve 181 disposed at the burning air inflow path 133
through the electric feedback control so as to open the electric
valve 181 with the optimal burning air supplying state. Therefore,
the flames on the combustor 140 are optimally sustained stably.
[0155] Then, the exhaust gas in the combustion chamber 110 and the
high temperature combustion gas formed by the flames on the
combustor 140 are mixed, and such a high temperature mixed gas
flows into the diesel particulate filter 400.
[0156] During the above operations, the temperature and the
pressure sensors 191a, 191b, 194a and 194b measure the temperatures
and pressures at the front end and the rear end of the diesel
particulate filter 400 and transmit signals of the measured
temperature and pressure to the control unit 170. Then, the control
unit 170 operates as follows after receiving the measured
temperature and pressure.
[0157] If the temperature T1 at the front end of the diesel
particulate filter 400 is lower or higher than the oxidization
temperature (TR) of the soot particles, the control unit 170
feedback controls the amount of flowing the fuel from the fuel pump
123 and the level of opening the electric valves 181 and 182 so as
to sustain the optimal temperature through increasing or reducing
the temperature at the front end of the diesel particulate filter
400.
[0158] Then, the control unit 170 calculates the pressure
difference ?P between the front end and the rear end of the diesel
particulate filter 400 using the temperatures T1 and T2 and the
pressures P1 and P2 at the front end and the rear end of the diesel
particulate filter 400, and compares the calculated pressure
difference .DELTA.P with the preset initial pressure difference
.DELTA.PI. If the initial pressure difference is greater than the
calculated pressure difference, the above described operations are
continuously performed. If the calculated pressure difference is
smaller than or equal to the pressure difference between the front
end and the rear end of the diesel particulate filter 400 after
finishing regenerating the diesel particulate filter 400, the
control unit 170 operates as follows.
[0159] The control unit 170 transmits a signal to the fuel pump 122
to stop the fuel pump 122 in order to extinguish the flames on the
combustor 140.
[0160] Herein, the stopped fuel pump 122 is reset as an initial
state.
[0161] After stopping the fuel pump 122, the flame sensor 160
transmits a flame extinguishing signal to the control unit 170, and
the control unit 170 closes the electric valve 181 disposed at the
burning air inflow path 133 after passing a predetermined time in
order to prevent the flames from being reformed. Then, the control
unit 170 closes the electric valve 182 disposed at the convey air
flow path 124.
[0162] These operations are repeatedly performed according to the
pressure difference between the front end and the rear end of the
diesel particulate filter 400, which are transmitted to the control
unit 170, so as to normally drive the diesel particulate filtering
apparatus 1000.
[0163] Meanwhile, if the flame on the combustor 140 is extinguished
without finishing regenerating the diesel particulate filter 400
while regenerating the diesel particulate filter 400, the control
unit 170 operates as follows.
[0164] If the flame on the combustor 140 is extinguished without
finishing regenerating the diesel particulate filter 400 while
regenerating the diesel particulate filter 400, the control unit
170 stops the fuel pump 122 by transmitting an operation stop
signal to the fuel pump 133 at the moment of receiving the flame
extinguishing signal from the flame sensor 160 in order to prevent
the fuel from be discharged to the combustion chamber 110 through
the combustor 140. Then, in order to discharge the fuel leaked to
the combustion chamber 110, the igniting operation, the flame
stabilizing operation and the filter regenerating operation are
re-performed after passing predetermined time.
[0165] Since the filter regenerating operation is performed based
on the pressure difference between the front end and the rear end
of the diesel particulate filter 400 as a reference time, that is,
since the condition .DELTA.P=.DELTA.PR is the reference time for
performing the filter regenerating operation, it is required to
distinguish the igniting operation of the condition
.DELTA.P<.DELTA.PR such as a re-igniting operation caused when
the flame is extinguished during regenerating a filter and it must
be controlled differently.
[0166] In other words, the filter regenerating operation is not
required performed while the diesel particulate filter 400 are
collecting the soot particles after the burner 100 finishes the
regeneration of the diesel particulate filter 400 although the
condition is .DELTA.P<.DELTA.PR. However, the filter
regenerating operation must be continuously performed until the
condition .DELTA.P=.DELTA.PR is reached by re-igniting the flame if
the flame is extinguished while regenerating the diesel particulate
filter.
[0167] Therefore, in order to clearly distinguish an operation
requiring the re-igniting operation based on the condition
.DELTA.P<.DELTA.PR, the control unit 170 may include control
variables for denoting the directivity of operating the diesel
engine particulate filtering apparatus 1000. For example, the
control unit 170 may set the control variables that denote the
directivities of operations in the diesel engine particulate
filtering apparatus 1000 as follows. At first, the control unit 170
sets a directivity of starting the control unit 170 as a reference
number, for example, zero when the engine starts. While the diesel
particulate filter 400 is collecting the soot particles, the
control unit 170 sets the directivity thereof as a positive number
by adding a predetermined positive number to the reference number.
Herein, the directivity for the operation of collecting the soot
particles is always set as the positive number. When the
regeneration condition of the diesel particulate filter is reached,
the control unit 170 resets the directivity thereof as the
reference point, zero. When the regeneration of the diesel
particulate filter 400 starts, the control unit 170 sets the
directivity thereof as an negative number by adding a predetermined
negative number to the reference number or subtracting a
predetermined positive number from the reference number. When the
regeneration of the diesel particulate filter 400 ends, the control
unit 170 sets the directivity thereof as the reference number,
zero. While driving the diesel engine particulate filtering
apparatus 1000, the control unit 170 repeatedly performs these
operations for setting the directivity thereof. As described above,
the driving directivity of the diesel engine particulate filtering
apparatus 1000 may be set by the control unit 170.
[0168] Therefore, the control unit 170 does not transmit any
signals related to the operations of the burner 100 if
.DELTA.PE<.DELTA.P<.DELTA.PR and the directivity is the
positive number. Also, the control unit 170 transmits a signal to
drive the burner 100 if .DELTA.PE<.DELTA.P<.DELTA.PR and the
directivity is the negative number.
[0169] Herein, if the condition is .DELTA.P.gtoreq..DELTA.PR, the
control unit 170 transmits the signal to drive the burner 100
regardless of the sign of the directivity. Also, if the condition
is .DELTA.P.ltoreq..DELTA.PE, the control unit 170 transmits a
signal to stop the burner 100 regardless of the sign of the
directivity.
[0170] As described above, the PR can be used as a reference to
transmit a signal to start the regeneration of the diesel
particulate filter 400. Also, the mass of the soot particles
trapped at the diesel particulate filter 400 may be used as a
reference to start the regeneration as like as the PR with the
identical method of controlling the diesel engine particulate
filtering apparatus and transmitting signals to control
thereof.
[0171] Furthermore, the control unit 170 may set and control safety
features and alarm systems for preparing the emergency situation
such as a dangerous situation happened while driving the diesel
engine particulate filtering apparatus 1000. Such an operation of
the control unit 170 will be described hereinafter.
[0172] As described above, the safety of the diesel engine
particulate apparatus 1000 is very closely related to controlling
the flames because the diesel engine particulate filtering
apparatus 1000 forms flames inside thereof. As a safety feature,
the control unit 170 includes a compulsive control function 171 for
compulsory controlling a switch 172 for the fuel pump 122 when the
control unit 170 senses the abnormal operation of the diesel engine
particulate filtering apparatus 1000, such as when the control unit
170 becomes unable to extinguish the flames of the combustor 140,
when the control unit 170 becomes unable to ignite the flames on
the combustor 140, when the control unit 170 becomes unable to stop
supply the fuel from the fuel pump 122. In these cases, the
compulsive control function 171 compulsory turns off the switch 172
to compulsory short the power supply to the fuel pump 122.
Furthermore, an alarm system may be included for noticing a driver
of a vehicle to recognize the abnormal driving state.
[0173] In order to prepare the backflow of the flames caused by the
abnormal driving, a backflow blocking unit may be disposed at the
first mixed gas inflow path 125 for blocking the flame, and a flame
sensor may be further disposed in the first mixed gas inflow path
125 and the fuel injection nozzle 130 in order to sense the
backflow of the flame.
[0174] Also, a cooling unit may be disposed in paths of flowing the
fuel such as the first mixed gas inflow path 125 and the fuel
injection nozzle 130 in order to prevent the fuel to be ignited by
the heat made from the high temperature exhaust gas from the
engine.
[0175] In addition, an explosion preventing valve 173 may be
disposed at the combustion chamber 110 in order to prevent the
combustion chamber 110 from being exploded by abnormally burning
the unburned fuel that is excessively discharged from the fuel
tank.
[0176] Also, a noise blocking unit may be included to block the
noise that influences the control unit 170.
[0177] As described above, the regeneration operation of diesel
engine particulate filtering apparatus 1000 is very stably and
continuously performed while the engine is driving. Also, the
control unit 170 controls the diesel engine particulate filtering
apparatus 1000 to stably sustain the flames on the combustor 140
without extinguishing the flame while the driving conditions of the
engine abruptly change through automatically controlling the
amounts of the fuel, the air for burning, and the air for conveying
to be optimal state according to driving condition variation.
[0178] Furthermore, the combustor 140 forms a plurality of very
short flames at the same time through the fine flame holes formed
on the combustor 140 because the combustor 140 is made of porous
metal fiber. Also, the accumulated heat formed on the surface of
the combustor 140 prevents the flames of the combustor 140 from
being easily extinguished and enables the flames to be ignited on
the entire surface of the combustor 140 in a short time.
[0179] Moreover, since the flame holder 111 having the one-layered
porous wall is disposed to surround the combustor 140, the surface
of the combustor 140 is sufficiently heated although the driving
condition varies abruptly, for example, when the engine accelerates
and decelerates.
[0180] In addition, since the size of the flame is very small, the
flames and the swirling flow are formed with very small variation.
Therefore, the combustor 140 stably sustains the flames on the
combustor 140 although the amount of the exhaust gas flow changes
abruptly.
[0181] That is, the diesel engine particulate filtering apparatus
1000 according to the present invention can stably sustain the
flames in the exhaust gas flow when the diesel engine is regularly
driven, for example, when the engine is kept ticking over, and when
the engine is driven at a constant speed. Furthermore, the diesel
engine particulate filtering apparatus 100 according to the present
invention can ignite, extinguish and stably sustain the flames on
the combustor although the pressure and the amount of the exhaust
gas flow change abruptly due to the abrupt variation of the engine
load.
[0182] The burners according to the embodiments of the present
invention were described to have a singularity of carburetor 120,
fuel injection nozzle 130, combustor 140, and igniter 150. However,
the present invention is not limited thereby. The burner 100 may
include a plurality of carburetors, fuel injection nozzles,
combustors and igniters.
[0183] While the present invention has been described with respect
to certain preferred embodiments, it will be apparent to those
skilled in the art that various changes and modifications may be
made without departing from the scope of the invention as defined
in the following claims.
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