Valve arrangement
US6398181B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 14, 1999 |
| Grant date | Jun 4, 2002 |
| Priority date | — |
| Expiry date | Dec 14, 2019 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF15B2211/8757
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A valve arrangement (10) for hydraulically actuated machinery installations, especially for powered support assemblies in underground mining, with hydraulically actuated working valves (12, 13, 14) to control hydraulic cylinders (11) or other hydraulically actuated machinery units of the machinery installation and with pilot valves (15) controlling the working valves. In order to avoid the pilot valves (15) and working valves (12, 13, 14) entering an unstable operating condition in the event of a falling off of pressure in the hydraulic fluid supply to the valves, and opening and closing in an uncontrollable and undesired manner, the pilot valves (15) are attached to their own pressure medium supply (17), separate or separable from the hydraulic fluid supply (20) to the working valves (12, 13, 14), so that pressure variations in the hydraulic fluid supply circuit do not affect the pressure medium for the switching of the working valves (12, 13, 14), but the pressure in them is maintained largely constant.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.