Hydraulic drive system
US6105367A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 29, 1998 |
| Grant date | Aug 22, 2000 |
| Priority date | — |
| Expiry date | May 29, 2018 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF15B2211/71
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A hydraulic drive system wherein differential pressures across flow control valves are controlled by pressure compensating valves to become the same value, i.e., a differential pressure .DELTA.PLS, and the differential pressure .DELTA.PLS is maintained at a target differential pressure .DELTA.PLSref by a pump displacement control system. For modifying the target differential pressure .DELTA.PLSref depending on change in rotational speed of an engine, a flow rate detecting valve is disposed intermediate between delivery lines of a fixed displacement hydraulic pump and a differential pressure .DELTA.Pp across a variable throttle of the flow rate detecting valve is introduced to a setting modifying unit to thereby modify the target differential pressure .DELTA.PLSref. The flow rate detecting valve changes an opening area of the variable throttle depending on the differential pressure .DELTA.Pp depending on the rotational speed of the engine.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.