Valve control apparatus and method for internal combustion engine
US6755165B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 27, 2003 |
| Grant date | Jun 29, 2004 |
| Priority date | — |
| Expiry date | Feb 27, 2023 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF01L2820/041
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
The invention controls the opening of an oil control valve (OCV), which controls the operation of a variable valve timing mechanism in an internal combustion engine, according to a duty ratio of a driving pulse signal. An electronic control unit (ECU) performs feedback control on a duty ratio DR of the driving pulse signal during ordinary operation based on a target value and an actual value of the valve timing. When the oil temperature is low (i.e., when the operating oil viscosity is high), the ECU controls the valve timing of the engine by repeating an inching operation that maintains the duty ratio DR of the signal at a large value (i.e., 0% or 100%) for a predetermined hold time so as to operate the variable valve timing mechanism, and then maintaining the duty ratio DR of the signal at a value (50%) that does not operate the variable valve timing mechanism.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.