Valve timing controller for internal combustion engine
US6968817B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 10, 2004 |
| Grant date | Nov 29, 2005 |
| Priority date | — |
| Expiry date | Nov 10, 2024 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/12
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A controller for a lock mechanism of an engine valve that readily performs unlocking. A VVT changes the rotational phase of a camshaft relative to a pulley in accordance with the difference between the hydraulic pressure of an advance pressure chamber and the hydraulic pressure of a delay pressure chamber to vary the valve timing. The hydraulic pressure difference is set by a variable command value. A lock mechanism engages a lock pin with a lock hole when the rotational phase of the camshaft matches a lock phase. The VVT enters the most easily unlocking hydraulic pressure state when the command value is set at an unlocking command value. An ECU gradually increases the command value from a lower limit value to the unlocking command value and then to the upper limit value to unlock relative rotation of the camshaft.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.