Catalyst warm up control for diesel engine
AssigneeToyota Jidosha Kabushiki Kaisha
InventorsShizuo Sasaki, Kouji Yoshizaki, Nobuki Kobayashi, Yoshiki Hashimoto
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Abstract
Diesel engine is operated in a first warm-up mode in an early warm-up period after startup so as to accelerate activation of the catalyst, and then in a second warm-up mode in a late warm-up period after the early warm-up period so as to maintain activity of the catalyst. The first warm-up mode provides more energy to the catalyst with exhaust gases than the normal operation mode of the diesel engine. The second warm-up mode provides exhaust gases of higher temperature to the catalyst than the normal operation mode.
Claims34
A diesel engine comprising:
- a combustion chamber;
- a fuel injection device for injecting fuel into the combustion chamber;
- a catalyst for purifying exhaust gases from the combustion chamber;
- and
- a controller for controlling a plurality of devices of the diesel engine including the fuel injection device;
- wherein the controller is configured to perform operation in a first warm-up mode in an early warm-up period after startup of the diesel engine, and to perform operation in a second warm-up mode in a late warm-up period after the early warm-up period, so as to accelerate and maintain activation of the catalyst;
- wherein the first warm-up mode is configured to provide more energy to the catalyst with exhaust gases than a normal operation mode of the diesel engine, the normal operation mode being performed after the late warm-up period;
- wherein the second warm-up mode is configured to provide exhaust gases of higher temperature to the catalyst than the normal operation mode;
- and
- wherein the second warm-up mode provides a smaller exhaust gas flow to the catalyst than both the first warm-up mode and the normal operation mode.
An operation method of a diesel engine including a combustion chamber, a fuel injection device for injecting fuel into the combustion chamber, and a catalyst for purifying exhaust gases from the combustion chamber, the method comprising the steps of:
- performing engine operation in a first warm-up mode in an early warm-up period after startup of the diesel engine, so as to accelerate activation of the catalyst;
- performing engine operation in a second warm-up mode in a late warm-up period after the early warm-up period, so as to maintain activity of the catalyst,
- wherein the first warm-up mode is configured to provide more energy to the catalyst with exhaust gases than a normal operation mode of the diesel engine, the normal operation mode being performed after the late warm-up period;
- wherein the second warm-up mode is configured to provide exhaust gases of higher temperature to the catalyst than the normal operation mode;
- and
- wherein the second warm-up mode provides a smaller exhaust gas flow to the catalyst than both the first warm-up mode and the normal operation mode.
Dependencies are inferred from the claim text.