| 摘要 |
[Problem] To provide a hydraulic drive circuit that, in a hydraulic drive system widely used in construction machines, industrial apparatuses such as presses, and the like, can achieve high responsiveness, high precision, and high efficiency at a low cost. [Solution] This hydraulic drive circuit (1), which drives a hydraulic actuator (2) by means of supplying hydraulic fluid discharged from a main hydraulic fluid pump (P), is provided with: a first valve (4) that is disposed at a main tubing pathway (3) through which the hydraulic fluid discharged from the main hydraulic pump (P) flows to the hydraulic actuator (2); a second valve (5) for causing hydraulic fluid to flow into one fluid chamber of the hydraulic actuator (2) and for returning to a tank (T) the hydraulic fluid discharged from another fluid chamber; and a sub-hydraulic pump (7) that increases/amplifies the hydraulic fluid of the main tubing pathway (3) by a predetermined amount using the hydraulic fluid flowing to a branched tubing pathway (6) that branches from the main tubing pathway (3) between the main hydraulic fluid pump (P) and the drive switching valve (4). |
