Hydraulic circuit of construction machinery
US7272928B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 24, 2006 |
| Grant date | Sep 25, 2007 |
| Priority date | — |
| Expiry date | May 24, 2026 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF15B2211/781
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
To keep one of three hydraulic pumps unaffected by variations in torque of the remaining hydraulic pumps when the three hydraulic pumps are used, displacements of the first and second hydraulic pumps are controlled based on their own delivery pressures P1,P2 and a pressure P3′ obtained by reducing through a reducing valve 14 a delivery pressure P3 from the third hydraulic pump, while a displacement of the third hydraulic pump 3 is controlled only by its own delivery pressure P3. The pressure oil delivered from the third hydraulic pump 3, therefore, remains unaffected by variations in delivery flow rates from the first and second hydraulic pumps 1,2, in other words, by variations in their torque consumptions, so that the third hydraulic pump is assured to provide a stable flow rate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.