CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to Japanese Patent Application No.

2020-112221 filed on Jun. 30, 2020, incorporated herein by reference in its entirety.

BACKGROUND

1. Technical Field

The present disclosure relates to a control apparatus of an internal combustion engine, and, particularly, to a control apparatus of an in-vehicle internal combustion engine having a port injection valve and a cylinder injection valve.

2. Description of Related Art

As a control apparatus of this type of internal combustion engine, an apparatus that sets, when a fuel cut is ended and fuel injection is executed, an increase amount coefficient with respect to a base injection amount such that the increase amount coefficient in a case where a duration of the fuel cut is short is smaller than that in a case where the duration of the fuel cut is long has been proposed (see, for example, Japanese Unexamined Patent Application Publication No. 2016-151261). Since an engine or an intake-air port becomes cool when the duration of the fuel cut becomes long, it is necessary to increase an amount of fuel for fuel injection after returning from the fuel cut. In this case, since the engine or the intake-air port becomes cooler, as the duration of the fuel cut becomes longer, the amount of an increase in the fuel becomes great.

SUMMARY

In a control apparatus of an in-vehicle internal combustion engine having a port injection valve and a cylinder injection valve, an intake-air port becomes cooler by a fuel cut than a cylinder does. For this reason, when the fuel increase amount in fuel injection after returning from the fuel cut is the same for the port injection and the cylinder injection, combustion in the port injection, combustion in the cylinder injection, or combustion in both injections may become unstable.

A control apparatus of an internal combustion engine according to the present disclosure enables combustion after returning from a fuel cut to become more stable.

The control apparatus of the internal combustion engine according to the present disclosure employs configurations hereinbelow.

One aspect of the present disclosure is a control apparatus of an internal combustion engine. The internal combustion engine includes a cylinder injection valve that injects fuel into an intake-air port, and a cylinder injection valve that injects fuel into a cylinder. The control apparatus includes an electronic control unit configured to control the port injection valve and the cylinder injection valve such that when returning from a fuel cut that stops a fuel injection from the port injection valve and the cylinder injection valve, a value of a port increase amount correction that is a fuel increase amount correction in which a fuel amount is decreased with a lapse of time during a port injection differs from a value of a cylinder increase amount correction that is a fuel increase amount correction in which a fuel amount is decreased with a lapse of time during a cylinder injection. The fuel is injected from the port injection valve in the port injection and is injected from the cylinder injection valve in the cylinder injection.

In the control apparatus of the internal combustion engine according to the present disclosure, when returning from a fuel cut, a value of a port increase amount correction that is a fuel increase amount correction in which a fuel amount is decreased with a lapse of time during a port injection for injecting the fuel from the port injection valve differs from a value of a cylinder increase amount correction that is a fuel increase amount correction in which a fuel amount is decreased with a lapse of time during a cylinder injection for injecting the fuel from the cylinder injection valve. In other words, more appropriate port increase amount correction and cylinder increase amount correction are set and used. As a result, combustion after returning from the fuel cut can become more stable.

In the above aspect, the value of the port increase amount correction may be greater than the value of the cylinder increase amount correction. This is based on the fact that the intake-air port becomes cooler by the fuel cut than the cylinder does.

In the above aspect, the values of the port increase amount correction and the cylinder increase amount correction may become greater as a duration of the fuel cut becomes longer. This is based on the fact that the longer the duration of the fuel cut becomes, the cooler the intake-air port or the cylinder becomes.

In the above aspect, when returning from the fuel cut, the electronic control unit may control the port injection valve and the cylinder injection valve such that the port increase amount correction is switched to the cylinder increase amount correction with a lapse of time when the port injection is switched to the cylinder injection, and the cylinder increase amount correction is switched to the port increase amount correction with a lapse of time when the cylinder injection is switched to the port injection. As a result, during the execution of the increase amount correction after returning from the fuel cut, combustion can become more stable both when the port injection is switched to the cylinder injection and, conversely, when the cylinder injection is switched to the port injection.

