Safety circuit for a servo-hydraulic regulating system
US5490442A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 13, 1993 |
| Grant date | Feb 13, 1996 |
| Priority date | — |
| Expiry date | Sep 13, 2013 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA01B63/111
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A safety circuit for a servo-hydraulic regulating system for the hydraulic control and actuation of load units, such as operating tools on utility vehicles and agricultural machines. The controlling of the load unit is effected via a proportional valve which is actuated in dependence upon a pair of output signals of a measuring bridge in such a way that, in the event of a balanced measuring bridge, it assumes a neutral setting in which the operating line running to the load unit or emanating from the load unit is blocked. In order to prevent the lifting gear from executing a regulating reaction if the measuring bridge is out of tune when the servo-hydraulic regulating system is switched on, a safety valve arrangement is provided in the operating line. Depending on at least one control signal determined by the setting of the proportional valve, when the regulating system is switched on, the operating line is blocked until, via the at least one control signal, the balance of the measuring bridge has been registered.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.