Lubeless valve assembly for engine
US8468994B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 3, 2011 |
| Grant date | Jun 25, 2013 |
| Priority date | — |
| Expiry date | Oct 23, 2031 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF01L2301/00
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A valve assembly includes a tubular valve stem guide and a valve having a valve stem slidable in the bore of the valve stem guide. A lower valve stem seal has an annular body surrounding the valve stem and a skirt sealing with the valve stem guide. An upper valve stem seal has an annular body sealingly mounted on the valve stem and a skirt portion overlapping with the annular body of the lower valve stem seal during the reciprocating movement of the valve stem so that the upper and lower valve stem seals cooperate to prevent flow of oil to the bore of the valve stem guide. The valve stem is coated with a diamond-like carbon coating or a hard nitride coating, and the valve stem guide is of powered metal construction with approximately 1% by weight solid lubricant such as molybdenum disulfide or tungsten disulfide.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.