JP-7856063-B2 - Engine control device

Inventors

• 花井 紀仁
• 千田 健次
• 細木 貴之

Assignees

• トヨタ自動車株式会社

Dates

Publication Date

20260511

Application Date

20230704

Claims (4)

1. An engine control device that performs peripheral learning on an ignition timing map, which is a predetermined relationship between an operating point consisting of the load factor and rotational speed of the engine used to set the ignition timing of the engine, updates the ignition timing of the operating point related to the learning using the learned value when the ignition timing of the engine is learned, and updates the ignition timing of the surrounding operating points, which are the immediate and next-immediate operating points of the operating point related to the learning, using values corresponding to the learned value. Peripheral learning is performed only on the ignition timing of operating points in the vicinity of the operating point related to the learning, specifically those operating points whose ignition timing falls within a predetermined range from the learned value. An engine control device characterized by the following features.
2. An engine control device according to claim 1, When learning the ignition timing of the driving point related to the learning in the advance direction, peripheral learning is performed only on the ignition timing of the driving points in the surrounding area whose ignition timing is within the range from the learned value to the predetermined value in the advance direction. When learning the ignition timing of the driving point related to the learning in the retard direction, peripheral learning is performed only on the ignition timing of the driving points in the surrounding area whose ignition timing is within the range from the learned value to the predetermined value in the retard direction. Engine control device.
3. An engine control device according to claim 1 or 2, When learning the ignition timing of operating points surrounding the aforementioned learning operating point, the ignition timing is learned such that the operating point closer to the learning operating point is more significantly affected by the learned value. Engine control device.
4. An engine control device according to claim 1 or 2, The operating point of the engine is represented by the load factor of the engine and the rotational speed of the engine. Engine control device.

Description

This disclosure relates to an engine control device, and more particularly to an engine control device that learns an ignition timing map used to set the ignition timing of an engine. Conventionally, control devices for this type of engine have been proposed that calculate ignition timing based on basic learned values, multi-point learned values, and basic ignition timing (see, for example, Patent Document 1). In this control device, multiple basic learning regions are defined based on the engine's operating conditions, and multiple multi-point learning regions are defined within one of these basic learning regions based on the engine's operating conditions. The basic learned values are updated when the engine's operating state is in one of the basic learning regions, and the multi-point learned values are updated when the engine's operating state is in one of the multi-point learning regions. Japanese Patent Publication No. 2010-209886 This is a schematic diagram showing the general configuration of an engine device 10 equipped with an engine control device according to an embodiment.This flowchart shows an example of the ignition timing learning process performed by the electronic control unit 40.This is an explanatory diagram showing an example of an ignition timing map that illustrates an example of the relationship between the load factor KL, rotational speed Ne, and ignition timing θ as operating points for engine 12. Embodiments of this disclosure will be described with reference to the drawings. Figure 1 is a schematic diagram showing the general configuration of an engine system 10 equipped with an engine control device according to an embodiment. As shown in the figure, the engine system 10 comprises an engine 12 and an electronic control unit 40. The engine system 10 is installed, for example, in a vehicle that runs using power from the engine 12, or in a hybrid vehicle that has an engine 12 in addition to a motor. The electronic control unit 40 corresponds to the engine control device. The engine 12 is configured as a four-cylinder internal combustion engine that outputs power through four strokes: intake, compression, expansion (explosive combustion), and exhaust, using a mixed fuel of gasoline and alcohol (e.g., ethanol) from a fuel tank. This engine 12 includes a port injection valve 26 that injects fuel into the intake port, an in-cylinder injection valve 27 that injects fuel into the cylinder, and a spark plug 30. The in-cylinder injection valve 27 is positioned approximately in the center of the top of the combustion chamber 29 and injects fuel in a spray form. The spark plug 30 is positioned near the in-cylinder injection valve 27 so as to ignite the fuel sprayed from the in-cylinder injection valve 27. The engine 12 is equipped with a port injection valve 26 and an in-cylinder injection valve 27, allowing it to operate by switching the injection mode Mi between port injection mode, in-cylinder injection mode, and shared injection mode based on the operating state of the engine 12, and by switching the number of in-cylinder injections Nd, which is the number of injections by the in-cylinder injection valve 27 in the in-cylinder injection mode and shared injection mode. In port injection mode, air cleaned by the air cleaner 22 is drawn into the intake manifold 23 and passes through the throttle valve 24 and surge tank 25, while fuel is injected from the port injection valve 26 downstream of the surge tank 25 in the intake manifold 23 to mix the air and fuel. Subsequently, this mixture is drawn into the combustion chamber 29 via the intake valve 28 and explodes and burns due to an electric spark from the spark plug 30. The reciprocating motion of the piston 32, which is pushed down in the cylinder bore 31 by the energy generated, is then converted into rotational motion of the crankshaft 14. In the in-cylinder injection mode, air is drawn into the combustion chamber 29, similar to the port injection mode. Fuel is injected from the in-cylinder injection valve 27 in one or multiple bursts during the intake and compression strokes, and the resulting explosive combustion is caused by an electric spark from the spark plug 30 to generate rotational motion of the crankshaft 14. In the shared injection mode, fuel is injected from the port injection valve 26 when air is drawn into the combustion chamber 29, and also from the in-cylinder injection valve 27 in one or multiple bursts during the intake and compression strokes. The resulting explosive combustion is caused by an electric spark from the spark plug 30 to generate rotational motion of the crankshaft 14. The exhaust gas discharged from the combustion chamber 29 through the exhaust valve 33 to the exhaust pipe 34 is discharged to the outside air via a purification device 35. The purification device 35 has a catalyst (three-way catalyst) 35a that purifies harmful components such as carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (N