Variable valve lift mechanism used in an internal combustion engine
US4258671A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 6, 1979 |
| Grant date | Mar 31, 1981 |
| Priority date | — |
| Expiry date | Feb 6, 1999 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF01L13/0031
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A hydraulic tappet is used in a variable valve lift engine. The tappet comprises an outer case having a pressure chamber formed therein, an inner case having an oil chamber formed therein and engaged within the outer case, and a check valve disposed between the pressure chamber and the oil chamber. The pressure chamber is communicated with an electromagnetic valve via an additional check valve. The electromagnetic valve is actuated in accordance with changes in operating conditions of an engine, i.e. the engine load and the temperature of the engine, so that the oil pressure between the additional check valve and the electromagnetic valve is maintained at a predetermined level. As a result, the valve lift of the engine can be varied at an optimum level in accordance with changes in the operating conditions of the engine.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.