Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
172 words
An internal combustion engine characterized by being provided with fuel injectors which enable high pressure fuel to be directly injected into combustion chambers of the engine, spark plugs which are provided in the combustion chambers, a catalytic converter provided in the middle of the exhaust pipe for purifying the exhaust, a temperature sensor for detecting the temperature of a catalyst of the catalytic converter and a control unit which receives as input the engine rotational speed, load, and the detection value of the catalyst temperature sensor for controlling the engine, where, when the temperature of the catalyst is lower than a predetermined target temperature, the fuel injectors inject additional fuel into the combustion chambers under the instruction of the control unit during at least one of the expansion and the exhaust strokes to mix it with the exhaust and wherein the internal combustion engine includes means for reigniting and burning the mixture of exhaust and additional fuel upstream of the catalytic converter so as to heat the catalyst to the target temperature.
Claim 2
Dependent Claim
172 words
An internal combustion engine characterized by being provided with fuel injectors which enable high pressure fuel to be directly injected into combustion chambers of the engine, spark plugs which are provided in the combustion chambers, a catalytic converter provided in the middle of the exhaust pipe for purifying the exhaust, a temperature sensor for detecting the temperature of a catalyst of the catalytic converter and a control unit which receives as input the engine rotational speed, load, and the detection value of the catalyst temperature sensor for controlling the engine, where, when the temperature of the catalyst is lower than a predetermined target temperature, the fuel injectors inject additional fuel into the combustion chambers under the instruction of the control unit during at least one of the expansion and the exhaust strokes to mix it with the exhaust and wherein the internal combustion engine includes means for reigniting and burning the mixture of exhaust and additional fuel upstream of the catalytic converter so as to heat the catalyst to the target temperature.
Claim 3
Dependent Claim
56 words
An internal combustion engine as set forth in claim 1, characterized in that the catalytic converter houses a three-way catalyst and the additional fuel injected into the combustion chambers under the instruction of the control unit is supplied upstream of the catalytic converter so that the air-fuel ratio of the exhaust becomes the stoichiometric air-fuel ratio.
Claim 4
Dependent Claim
30 words
An internal combustion engine as set forth in claim 1, characterized in that the reignition of the exhaust is performed by reenergizing the spark plugs provided in the combustion chambers.
Claim 5
Dependent Claim
38 words
An internal combustion engine as set forth in claim 1, wherein said means for reigniting and burning the mixture of exhaust and additional fuel ignites the mixture of exhaust and fuel at the end of the exhaust stroke.
Claim 6
Dependent Claim
44 words
An internal combustion engine as set forth in claim 1, characterized in that discrete portions of a total amount of additional fuel to be supplied in the combustion chambers by the fuel injectors are injected at predetermined times during the expansion and exhaust strokes.
Claim 7
Dependent Claim
25 words
An internal combustion engine as set forth in claim 1, characterized in that a second plug is provided in the middle of the exhaust passage.
Claim 8
Dependent Claim
20 words
An internal combustion engine as set forth in claim 6, characterized in that the second plug is a spark plug.
Claim 9
Dependent Claim
20 words
An internal combustion engine as set forth in claim 6, characterized in that the second plug is a glow plug.
Claim 10
Dependent Claim
28 words
An internal combustion engine as set forth in claim 6, characterized in that the second plug is provided in the middle of a cavity of the exhaust passage.
Claim 11
Dependent Claim
26 words
An internal combustion engine as set forth in claim 6, characterized in that the second plug is provided in a stepped portion of the exhaust passage.
Claim 12
Dependent Claim
33 words
An internal combustion engine as set forth in claim 1, characterized in that the additional fuel injection and the reignition are stopped when the temperature of the catalyst exceeds a predetermined target value.