Valve train for automotive engine
US5048474A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 13, 1990 |
| Grant date | Sep 17, 1991 |
| Priority date | — |
| Expiry date | Feb 13, 2010 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T74/2101
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
In a valve train for an I.C. engine, a cam shaft has cams formed with compound curvatures which allow the valve timing to be altered while the engine is operating, to suit the engine driving conditions by shifting the cam shaft along its axis. To reduce the force necessary to shift the cam shaft along its axis the valve closure springs are replaced by closure cams. In some embodiments pivoting arrangements comprising a pair of ball and socket joints are provided to eliminate lateral sway of the rocker arms allowing precise adjustment of the valve timing when the cam shaft is shifted along its axis. In other embodiments the rocker arms are journalled on a rocker shaft provided with stops for preventing lateral sway. In some embodiments the closure rocker arms have cupped ends in which either the valve stem retainer or the valve stem seal is received.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.