Construction machine
US11970838B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 25, 2020 |
| Grant date | Apr 30, 2024 |
| Priority date | — |
| Expiry date | Feb 6, 2041 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF15B2211/785
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
Provided is a construction machine in which travel operability is not impaired when a combined operation is performed in which a single-rod hydraulic cylinder is driven during a travel operation. A hydraulic excavator includes a controller that controls the delivery direction and delivery flow rate of a closed-circuit pump, opens and closes a travel switching valve and an assist switching valve, and controls the delivery flow rate of the open-circuit pump, according to a travel operation lever and a work operation lever. The controller holds the assist switching valve in a closed position irrespective of whether or not the work operation lever is operated in a case where the travel operation lever is operated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.