Internal combustion engine control apparatus

Patent metadata

Field	Value
Publication number	US-9416747-B2
Application number	US-201114343989-A
Country	US
Kind code	B2
Filing date	Sep 14, 2011
Priority date	Sep 14, 2011
Publication date	Aug 16, 2016
Grant date	Aug 16, 2016

Abstract

In a dual-fuel injection operation, when a fuel injection time by a direct injector as determined on the basis of a direct fuel pressure is less than a minimum value, a dual-injection is performed with a duel injection rate such that the amount of fuel injected by the direct injector is greater than when the dual-injection is performed with a duel injection rate which is determined in accordance with an engine operation state. Thus, the amount of fuel injected by the direct injector is increased, so that the high-temperature fuel that has remained in a high-pressure fuel pipe connected to the injector is rapidly injected and consumed. As a result, the direct fuel pressure can be rapidly lowered, whereby the fuel injection time by the direct injector for implementing an amount of fuel injection in accordance with a direct injection command value can be rapidly increased to the minimum value.

First claim

The invention claimed is:

1. A control apparatus for an internal combustion engine, the control apparatus being employed for an internal combustion engine having a port injector for injecting fuel to an intake port and a direct injector for injecting fuel into a cylinder, wherein
the control apparatus performs dual-injection, in which fuel injection by an amount corresponding to an injection amount command value is carried out through injection from the port injector and injection from the direct injector in a manner divided based on a dual-injection rate, which is determined in accordance with an engine operating state,
the control apparatus comprising an injection control section, wherein, when performing the dual-injection, if a fuel injection time of the direct injector that is determined based on the pressure of fuel supplied to the direct injector is less than a minimum value determined by the structure of the direct injector, the injection control section performs the dual-injection in which fuel of the amount corresponding to the injection amount command value is injected at such a dual-injection rate that the fuel injection from the direct injector is more than that in the dual-injection in which fuel of the amount corresponding to the injection amount command value is injected at the dual-injection rate determined in accordance with the engine operating state,
wherein the injection control section performs a first dual-injection or a second dual-injection as the dual-injection at the dual-injection rate at which the fuel injection from the direct injector is more than the fuel injection in the dual-injection at the dual-injection rate determined in accordance with the engine operating state,
in the first dual-injection, the direct injector injects fuel for the fuel injection time of the direct injector that is set to the minimum value and the port injector injects, out of the amount of fuel corresponding to the injection amount command value, fuel of an amount that cannot be injected by the direct injector, and
the second dual-injection sets the dual-injection rate to a value at which fuel is injected solely from the direct injector,
the injection control section gives priority to the first dual-injection rather than the second dual-injection, and carries out the second dual-injection instead of the first dual-injection when the amount of fuel injected from the port injector is small to such an extent that the fuel injection time of the port injector in the first dual-injection must be set to a value less than a minimum value determined by the structure of a port injector.

2. The control apparatus according to claim 1 , wherein
during the execution of the dual-injection at the dual-injection rate at which the fuel injection from the direct injector is more than that in the dual-injection at the dual-injection rate determined in accordance with the engine operating state, if the fuel injection time of the direct injector that is determined based on the pressure of the fuel supplied to the direct injector on the assumption that the dual-injection is executed at the dual-injection rate obtained in accordance with the engine operating state is raised to the minimum value, the injection control section switches the dual-injection to the dual-injection at the dual-injection rate determined in accordance with the engine operating state.

3. The control apparatus according to claim 1 , further comprising an injection timing advancing section that advances fuel injection timing of the direct injector if, at the execution of the fuel injection from the direct injector, the pressure of fuel supplied to the direct injector is higher than a threshold value greater than a target value determined in accordance with the engine operating state.

4. The control apparatus according to claim 1 , further comprising a purge restricting section that restricts flow of gas from a canister into an intake system of the engine when the dual-injection is performed at the dual-injection rate at which the fuel injection from the direct injector is more than that in the dual-injection at the dual-injection rate determined in accordance with the engine operating state.

5. The control apparatus according to claim 4 , further comprising a timing control section that controls the injection control section and the purge restricting section such that the timing for starting restriction of the gas flow from the canister into the intake system of the engine is advanced relative to the timing for starting the dual-injection at the dual-injection rate at which the fuel injection from the direct injector is increased.

Assignees

• Mashiki Zenichiro
• Toyota Motor Co Ltd

Inventors

• Mashiki Zenichiro

Classifications

• F02D41/30 Primary

  Controlling fuel injection {(F02D41/182, F02D41/24 take precedence)} · CPC title

• Y02T10/44

  Cross-Sectional Technologies · mapped topic

• F02D41/0032

  Controlling the purging of the canister as a function of the engine operating conditions · CPC title

• F02D2200/0602

  Fuel pressure · CPC title

• F02D41/40

  with means for controlling injection timing or duration · CPC title