Hydraulic drive device for working machine
US9341198B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 17, 2012 |
| Grant date | May 17, 2016 |
| Priority date | — |
| Expiry date | Mar 16, 2033 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE02F9/2296
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A hydraulic drive device for a hydraulic excavator, includes: a first hydraulic pump; a first boom directional control valve and a second arm directional control valve which are connected in parallel to the first pump; a second hydraulic pump; and a second boom directional control valve and a first arm directional control valve which are connected in parallel to the second pump; wherein: the hydraulic drive device also includes: a third hydraulic pump; a third boom directional control valve connected to the third pump and controlling the flow of pressure oil supplied to a boom cylinder; and a third arm directional control valve connected in tandem with the third boom directional control valve and controlling the flow of pressure oil supplied to an arm cylinder.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.