Abstract: A controller for an internal combustion engine includes processing circuitry. The processing circuitry performs a dither control process. The dither control process includes a first mode in which a cylinder serving as a rich combustion cylinder is sequentially changed and a second mode in which a specified cylinder is fixed as one of a rich combustion cylinder and a lean combustion cylinder. The processing circuitry selects the first mode or the second mode based on an operating point of the internal combustion engine.

Abstract: A first limit requesting process limits a dither control process of fuel injection valves in such a manner that the absolute value of the difference between the air-fuel ratios of the cylinders becomes smaller when the degree of variation of the injection amounts of the fuel injection valves provided for respective cylinders is great than when the degree of variation is small. A second limit requesting process limits the dither control process in such a manner that the absolute value is smaller when the torque fluctuation amount of the internal combustion engine is great than when the torque fluctuation amount is small. The limiting process limits the dither control process in accordance with one of requests generated by the first limit requesting process and the second limit requesting process that causes the absolute value to be smaller than the other.

Abstract: A controller for an internal combustion engine includes processing circuitry. The processing circuitry performs a dither control process and a multi-injection process. Multiple injections in the multi-injection process includes a first injection and a second injection performed at a timing retarded from the first injection. The dither control process includes at least one of a process performed on a cylinder changed to a lean combustion cylinder so that a reduction amount of fuel injected through the first injection is greater than a reduction amount of fuel injected through the second injection and a process performed on a cylinder changed to a rich combustion cylinder so that an increase amount of fuel injected through the first injection is greater than an increase amount of fuel injected through the second injection.

Abstract: A controller learns the degree of variation in the injection amount of fuel injection valves provided for respective cylinders when the fuel injection valves are operated to control the air-fuel ratios of the respective cylinders to be equal to each other. A first advancement requesting process causes the request for the ignition timing to be more advanced when the degree of variation is great than when the degree of variation is small. A second advancement requesting process causes the request for the ignition timing to be more advanced when the torque fluctuation amount of the internal combustion engine is than when the torque fluctuation amount is small. The ignition control process controls the ignition timing in accordance with the request of the more advanced one of the first advancement requesting process and the second advancement requesting process.

Abstract: A first limit requesting process limits a dither control process of fuel injection valves in such a manner that the absolute value of the difference between the air-fuel ratios of the cylinders becomes smaller when the degree of variation of the injection amounts of the fuel injection valves provided for respective cylinders is great than when the degree of variation is small. A second limit requesting process limits the dither control process in such a manner that the absolute value is smaller when the torque fluctuation amount of the internal combustion engine is great than when the torque fluctuation amount is small. The limiting process limits the dither control process in accordance with one of requests generated by the first limit requesting process and the second limit requesting process that causes the absolute value to be smaller than the other.

Abstract: A controller learns the degree of variation in the injection amount of fuel injection valves provided for respective cylinders when the fuel injection valves are operated to control the air-fuel ratios of the respective cylinders to be equal to each other. A first advancement requesting process causes the request for the ignition timing to be more advanced when the degree of variation is great than when the degree of variation is small. A second advancement requesting process causes the request for the ignition timing to be more advanced when the torque fluctuation amount of the internal combustion engine is than when the torque fluctuation amount is small. The ignition control process controls the ignition timing in accordance with the request of the more advanced one of the first advancement requesting process and the second advancement requesting process.

Abstract: A controller for an internal combustion engine includes processing circuitry. The processing circuitry performs a dither control process and a multi-injection process. Multiple injections in the multi-injection process includes a first injection and a second injection performed at a timing retarded from the first injection. The dither control process includes at least one of a process performed on a cylinder changed to a lean combustion cylinder so that a reduction amount of fuel injected through the first injection is greater than a reduction amount of fuel injected through the second injection and a process performed on a cylinder changed to a rich combustion cylinder so that an increase amount of fuel injected through the first injection is greater than an increase amount of fuel injected through the second injection.

Abstract: A controller for an internal combustion engine includes processing circuitry. The processing circuitry performs a dither control process. The dither control process includes a first mode in which a cylinder serving as a rich combustion cylinder is sequentially changed and a second mode in which a specified cylinder is fixed as one of a rich combustion cylinder and a lean combustion cylinder. The processing circuitry selects the first mode or the second mode based on an operating point of the internal combustion engine.

Abstract: A control apparatus for an internal combustion engine is provided. The control apparatus is equipped with an electronic control unit. A CPU with which this electronic control unit is equipped performs dither control for setting a first cylinder as a rich-burn cylinder whose air-fuel ratio is richer than a theoretical air-fuel ratio and setting each of second to fourth cylinders as a lean-burn cylinder whose air-fuel ratio is leaner than the theoretical air-fuel ratio, when a request to raise the temperature of a three-way catalyst is made. Then, the CPU reduces the degree of richness of the rich-burn cylinder and the degree of leanness of each of the lean-burn cylinders while continuing dither control, on the condition that fluctuations at a level equal to or higher than a predetermined value are caused in time-series data on the rotational speed resulting from the combustion in each of the cylinders.

Abstract: A control apparatus for an internal combustion engine is provided. The control apparatus is equipped with an electronic control unit. A CPU with which this electronic control unit is equipped performs dither control for setting a first cylinder as a rich-burn cylinder whose air-fuel ratio is richer than a theoretical air-fuel ratio and setting each of second to fourth cylinders as a lean-burn cylinder whose air-fuel ratio is leaner than the theoretical air-fuel ratio, when a request to raise the temperature of a three-way catalyst is made. Then, the CPU reduces the degree of richness of the rich-burn cylinder and the degree of leanness of each of the lean-burn cylinders while continuing dither control, on the condition that fluctuations at a level equal to or higher than a predetermined value are caused in time-series data on the rotational speed resulting from the combustion in each of the cylinders.

Abstract: The present invention has an object to enable a torque as required to be realized without being influenced by an operation state of an IN-VVT, which is a variable valve timing mechanism which changes a valve timing of an intake valve. For this purpose, a control device for an internal combustion engine provided by the present invention stores data that defines a relationship between an air quantity and a torque in an MBT in association with the operation state of the IN-VVT, and calculates a target air quantity for realizing a required torque based on the data. The control device calculates an actual air quantity which is actually realized by an operation of a throttle when operating the throttle to realize the target air quantity.

Abstract: The present invention is directed to fuel injection devices for internal combustion engines. An object of the present invention is to provide a fuel injection device for an internal combustion engine capable of identifying a non-contributing fuel quantity when port injection and cylinder injection are simultaneously performed. If an explosion count and a coolant temperature for any cycle can be acquired, they can be applied to a first map and a second map to thereby find non-contributing fuel for 100% port injection and non-contributing fuel for 100% cylinder injection, respectively. Each of these found values of the non-contributing fuel is multiplied by a corresponding injection share ratio during injection of the non-contributing fuel to thereby find non-contributing fuel that takes into account the injection share ratio. Finally, these values are added up to arrive at a non-contributing fuel requirement value.

Abstract: The present invention is directed to fuel injection devices for internal combustion engines. An object of the present invention is to provide a fuel injection device for an internal combustion engine capable of identifying a non-contributing fuel quantity when port injection and cylinder injection are simultaneously performed. If an explosion count and a coolant temperature for any cycle can be acquired, they can be applied to a first map and a second map to thereby find non-contributing fuel for 100% port injection and non-contributing fuel for 100% cylinder injection, respectively. Each of these found values of the non-contributing fuel is multiplied by a corresponding injection share ratio during injection of the non-contributing fuel to thereby find non-contributing fuel that takes into account the injection share ratio. Finally, these values are added up to arrive at a non-contributing fuel requirement value.

Abstract: The present invention has an object to enable a torque as required to be realized without being influenced by an operation state of an IN-VVT, which is a variable valve timing mechanism which changes a valve timing of an intake valve. For this purpose, a control device for an internal combustion engine provided by the present invention stores data that defines a relationship between an air quantity and a torque in an MBT in association with the operation state of the IN-VVT, and calculates a target air quantity for realizing a required torque based on the data. The control device calculates an actual air quantity which is actually realized by an operation of a throttle when operating the throttle to realize the target air quantity.