Hydraulic circuit for a valve operating mechanism for an internal combustion engine
US4800850A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 24, 1987 |
| Grant date | Jan 31, 1989 |
| Priority date | — |
| Expiry date | Dec 24, 2007 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02F2001/245
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A hydraulic circuit for a valve operating mechanism for an internal combustion engine which has a plurality of intake or exhaust valves normally urged in a valve closing direction, a plurality of adjacent rocker arms associated respectively with the intake or exhaust valves and pivotably supported on a rocker shaft. The rocker arms are pivotable by cams rotatable in synchronism with a crankshaft. A coupling mechanism is provided in the rocker arm selectively interconnecting and disconnecting adjacent rocker arms in response to oil pressure. A hydraulic circuit supplies oil pressure to the coupling means and an oil feed passage lubricates the cams. The hydraulic circuit and oil feed passage are connected in series to each other through a flow restriction and the hydraulic circuit includes a directional control valve for changing the direction of flow of lubricating oil supplied from an oil pump to cause the lubricating oil to flow from the oil feed passage to the hydraulic circuit during low-speed operation of the engine and to cause the lubricating oil to flow from the hydraulic circuit to the oil feed passage during high-speed operation of said engine to always provide the proper …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.