Variable-timing valve actuating mechanism
US4587934A · kind A · utility
Inventor
Key dates
| Filing date | May 16, 1983 |
| Grant date | May 13, 1986 |
| Priority date | — |
| Expiry date | May 16, 2003 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF01L2305/00
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A variable-timing valve actuating mechanism for an internal combustion engine having an axially movable cam shaft, movable by a governor device to a position proportional to engine rpm. A set of dual cams is provided for operating intake and exhaust valves with a uniform profile lobe effective only over an idle to medium rpm range and a non-uniform profile lobe effective only over a medium to maximum rpm range. A timing gear drives the cam shaft and utilizes a spiral spine drive to also advance and retard the cam shaft rotation proportional to the cam shaft axial position. The variable advance/retard action and the non-uniform cam lobe are selected to optimize valve overlap, valve opening angle, and valve timing as a function of rpm.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.