EP0879946A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
An internal combustion engine
Assignee: Toyota Motor Corp
•
Filing: 1998-05-19
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Granted: —
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Expires: 2018-05-19
Abstract
Abstract An internal combustion engine comprising an exhaust gas recirculation system, wherein the amount of EGR gas in the combustion chamber is made larger than the amount of EGR gas where the amount of soot produced peaks when the engine load is comparatively low so as to suppress the temperatures of the fuel and gas around the fuel at the time of combustion in the combustion chamber to a temperature lower than the temperature at which soot is produced. This prevents the production of soot and NOx in the combustion chamber.
Inventors
- 👤 Shizuo Sasaki
- 👤 Takekazu Ito
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 12:06
CPC Classifications
F; F02; F02D; F02D41/00; F02D41/0025; F02D41/0047; F02D41/005; F02D41/0057; F02B; F02B47/00; F02B47/04; F02B47/08; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12; Y02T10/40
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
118 words
An internal combustion engine in which an
amount of production of soot gradually increases and then
peaks when an amount of inert gas in a combustion chamber
increases, wherein the amount of the inert gas is made
larger than an amount of inert gas where the amount of
production of soot peaks to make the temperatures of the
fuel and gas around the fuel at the time of combustion in
the combustion chamber lower than a temperature at which
soot is produced, and an after treatment device for
purifying unburned hydrocarbons, which are exhausted from
the combustion chamber in the form of a precursor of soot
or a form before that, is arranged in an engine exhaust
passage.
Claim 2
Dependent Claim
49 words
An internal combustion engine as set forth in
claim 1, wherein the temperatures of the fuel and the gas
around the fuel at the time of combustion in the
combustion chamber are temperatures at which the amount
of NOx in the exhaust gas becomes around 10 ppm or less.
Claim 3
Dependent Claim
54 words
An internal combustion engine as set forth in
claim 1, wherein the temperatures of the fuel and the gas
around the fuel at the time of combustion in the
combustion chamber are made temperatures lower than the
temperatures at which soot is produced only when the
engine load is lower than a predetermined load.
Claim 4
Dependent Claim
34 words
An internal combustion engine as set forth in
claim 1, wherein said after treatment device is comprised
of a catalyst having an oxidation function for oxidizing
the unburned hydrocarbons exhausted from the combustion
chamber.
Claim 5
Dependent Claim
33 words
An internal combustion engine as set forth in
claim 4, wherein the catalyst is comprised of at least
one of the group of an oxidation catalyst, a three-way
catalyst, and an NOx absorbent.
Claim 6
Dependent Claim
70 words
An internal combustion engine as set forth in
claim 1, wherein the heat of combustion of the fuel is
mainly absorbed by the inert gas in the combustion
chamber and the amount of inert gas is preset so that
the temperatures of the fuel and the gas around the fuel
at the time of combustion in the combustion chamber
become temperatures lower than the temperature at which
soot is produced.
Claim 7
Dependent Claim
30 words
An internal combustion engine as set forth in
claim 1, wherein the majority of the inert gas is fed
into the combustion chamber at the time of the intake
stroke.
Claim 8
Dependent Claim
52 words
An internal combustion engine as set forth in
claim 7, wherein an exhaust gas recirculation apparatus
is provided for recirculating the exhaust gas exhausted
from the combustion chamber into an engine intake passage
and the majority of the inert gas is comprised of
recirculated exhaust gas recirculated in the engine
intake passage.
Claim 9
Dependent Claim
22 words
An internal combustion engine as set forth in
claim 8, wherein the exhaust gas recirculation rate is at
least about 55 percent.
Claim 10
Dependent Claim
45 words
An internal combustion engine as set forth in
claim 1, wherein the air fuel ratio in the combustion
chamber is made the stoichiometric air fuel ratio, a lean
air fuel ratio slightly leaner than the stoichiometric
air fuel ratio, or a rich air fuel ratio.
Claim 11
Dependent Claim
73 words
An internal combustion engine as set forth in
claim 1, wherein a combustion temperature controlling
means is provided for maintaining the temperatures of the
fuel and the gas around the fuel at the time of
combustion in the combustion chamber at a temperature
lower than the temperature at which soot is produced
regardless of the amount of fuel fed into the combustion
chamber when the engine load is lower than a
predetermined load.
Claim 12
Dependent Claim
66 words
An internal combustion engine as set forth in
claim 11, wherein the combustion temperature controlling
means is comprised of an exhaust gas recirculation
apparatus which recirculates exhaust gas exhausted from
an engine exhaust passage into an engine intake passage
and the amount of recirculated exhaust gas recirculated
in the engine intake passage is increased the more the
amount of fuel fed into the combustion chamber increases.
Claim 13
Dependent Claim
60 words
An internal combustion engine as set forth in
claim 11, wherein the combustion temperature controlling
means is comprised of a cooling apparatus for a
recirculated exhaust gas recirculated into an engine
intake passage from an engine exhaust passage and the
cooling capacity of the cooling apparatus is increased
the more the amount of fuel fed into the combustion
chamber increases.
Claim 14
Dependent Claim
43 words
An internal combustion engine as set forth in
claim 11, wherein the combustion temperature controlling
means controls a compression ratio of the engine and the
compression ratio of the engine is made lower the more
the fuel fed into the combustion chamber increases.
Claim 15
Dependent Claim
51 words
An internal combustion engine as set forth in
claim 11, wherein the combustion temperature controlling
means is comprised of an intake control valve arranged in
an engine intake passage and the opening degree of the
intake control valve is made lower the more the fuel fed
into the combustion chamber increases.
Claim 16
Dependent Claim
51 words
An internal combustion engine as set forth in
claim 11, wherein the combustion temperature controlling
means is comprised of an actuator for driving an intake
valve and the timing of opening of the intake valve is
made later by the actuator the more the fuel fed into the
combustion chamber increases.
Claim 17
Dependent Claim
75 words
An internal combustion engine as set forth in
claim 11, wherein the combustion temperature controlling
means controls the timing of injection of fuel to be
injected into the combustion chamber and the timing of
injection of the fuel is made the end stage of the
compression stroke when the amount of fuel fed into the
combustion chamber is small and is made later the more
the amount of fuel fed into the combustion engine increases.
Claim 18
Dependent Claim
133 words
An internal combustion engine as set forth in
claim 1, wherein a NOx absorbent which absorbs the NOx
contained in an exhaust gas when an air fuel ratio of an
inflowing exhaust gas is lean and releases the absorbed
NOx when the air fuel ratio of the inflowing exhaust gas
is the stoichiometric air fuel ratio or rich is arranged
in an engine exhaust passage and the temperatures of the
fuel and the gas around the fuel at the time of
combustion in the combustion chamber are made
temperatures lower than the temperature at which soot is
produced in an engine low load operating state and an air
fuel ratio in the combustion chamber is made the
stoichiometric air fuel ratio or rich when NOx is to be
released from the NOx absorbent.
Claim 19
Dependent Claim
26 words
An internal combustion engine as set forth in
claim 18, wherein an oxidation catalyst is arranged in
the engine exhaust passage upstream of the NOx absorbent.
Claim 20
Dependent Claim
42 words
An internal combustion engine as set forth in
claim 1, wherein the internal combustion engine is
comprised of a diesel engine and fuel is injected toward
the inside of the combustion chamber at least at the end
stage of the compression stroke.
Claim 21
Dependent Claim
39 words
An internal combustion engine as set forth in
claim 20, wherein fuel is injected toward the inside of
the combustion chamber in the initial stage of the intake
stroke in addition to the end stage of the compression
stroke.
References Cited (Backward Citations)
No citation records indexed.
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