Hydraulic circuit for operating plural actuators and its pressure compensating valve and maximum load pressure detector
US5481872A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 23, 1994 |
| Grant date | Jan 9, 1996 |
| Priority date | — |
| Expiry date | Sep 23, 2014 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF15B2211/78
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
Simultaneous operation efficiency in a case where a plurality of actuators are operated by one or a plurality of hydraulic pumps is improved. A delivery pressure passage (1a) of one hydraulic pump (1) and that (1a) of the other hydraulic pump (1) communicate with each other through a first short-circuit passage (39) via a pair of check valves (38, 38), and an unload valve (40) is provided in this first short-circuit passage (39). The load pressure introduction passages (6, 6) on the left and right hydraulic pumps (1, 1) communicate with each other through a second short-circuit passage (36) via a pair of check valves (35, 35), and a relief valve (37) is provided in this short-circuit passage (36). The unload valve (40) is unloaded by the differential pressure between the pump delivery pressure in the first short-circuit passage (39) and the load pressure in the second short-circuit passage (36), whereby a single relief valve (37) carries out a relieving operation both at the time of flow merging and at the time of flow branching to equalize the maximum pump delivery pressures. The set pressure of the relief valve (37) can be a high level so as to relieve the valve (37) under a pred…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.