Lost motion variable valve actuation systems and method
US12297757B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 24, 2022 |
| Grant date | May 13, 2025 |
| Priority date | — |
| Expiry date | Jan 24, 2042 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/12
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A compact, modular, lost motion variable valve actuation assembly includes a dry start hydraulic circuit to enable quick priming of a lost motion master-slave circuit from a dry start reservoir to the master piston chamber during engine start. Motion of the master piston on engine startup may draw in fluid from the dry start hydraulic circuit. The dry start components may be integrated into a compact modular rocker shaft pedestal package suitable for retrofit on existing engine head assemblies. The master piston may include a push tube interface that includes a deep push tube cavity and lubrication capabilities in the master piston that provides for improved wear, stability, easy installation and alignment. The slave piston may be provided with a valve catch to reduce valve closing velocity during cycles involving lost-motion.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.