Controllable hydraulic valve operating mechanism
US5765515A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 19, 1997 |
| Grant date | Jun 16, 1998 |
| Priority date | — |
| Expiry date | May 19, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S137/906
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
In a hydraulic operating mechanism for a valve which comprises a valve stem with first spring means acting on the valve stem in the valve closing direction, and second spring means acting at least intermittently on the valve stem in a valve opening direction, the compressing force of the second spring means is controlled hydraulically during the operation of the valve control device. In order to keep the control forces required for operating the valve as low as possible over its entire operating range, the second spring means comprises a spring combination composed of at least two springs which have different spring forces providing for a maximum spring force of the second spring means at the start of the valve opening stroke.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.