Flow rate control device in a hydraulic excavator
US6202411A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 29, 1999 |
| Grant date | Mar 20, 2001 |
| Priority date | — |
| Expiry date | Jul 29, 2019 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF15B2211/7053
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A flow rate control device in a hydraulic excavator, comprising a hydraulic pump which is driven rotatively by an engine, a hydraulic actuator which is driven by a hydraulic oil discharged from the hydraulic pump, a control valve which controls the supply of the hydraulic oil to the hydraulic actuator, an operating means which operates the control valve so as to change over the valve from one position to another, a relief valve disposed in a discharge oil path extending from the hydraulic pump to limit the maximum pressure in the discharge oil path, an operational condition detecting means for detecting an operational condition of the hydraulic actuator, a pump pressure detecting means for detecting the discharge pressure of the hydraulic oil discharged from the hydraulic pump, a flow rate adjusting means for adjusting the discharge flow rate of the hydraulic oil discharged from the hydraulic pump, and a control means to which are inputted detection signals from both the operational condition detecting means and the pump pressure detecting means. When a specific operational condition of the hydraulic actuator is detected and when the said discharge pressure is held at a predetermin…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.