Intake or exhaust valve actuator
US5231959A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 16, 1992 |
| Grant date | Aug 3, 1993 |
| Priority date | — |
| Expiry date | Dec 16, 2012 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02B3/06
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A hydraulic intake or exhaust valve actuator for an internal combustion engine has a generally cylindrical sleeve, a piston member formed with a head portion and a rod or shaft portion, and a rod bearing through which the rod portion slides axially. To accommodate wide temperature variations, the sleeve, piston member, and rod bearing, are all formed of the same material so as to have similar thermal expansion coefficients. Outer surfaces of the piston member head portion and rod portion are provided with a coating of titanium nitride, while corresponding inner surfaces of the sleeve and the rod bearing are provided with a hard coating of a different material, e.g. nickel boride. These coatings have different hardnesses, so that galling or adhesive contact is avoided.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.