The Ritsumeikan Trust

Mori Kogyo Co., Ltd.

Harutsugu Mizui

Sang-Ho Hyon

Etsuhiro Mori

A hydraulic drive circuit is provided that can achieve high responsiveness, high precision, and high efficiency at a low cost in a hydraulic drive system popularly used in an industrial machine such as a press machine, a construction machine, and the like. A hydraulic drive circuitsupplies pressured liquid discharged from a main hydraulic pump P to drive a hydraulic actuator, and includes a first valvearranged in a main flow linethat circulates pressured liquid discharged from the main hydraulic pump P to the hydraulic actuator, a second valveto return the pressured liquid flowing into one liquid chamber of the hydraulic actuatorand discharged from the other liquid chamber to a tank T, and a sub-hydraulic pumpthat is arranged between the main hydraulic pump P and the drive direction control valveand uses the pressured liquid flowing in a branched flow linebranched from the main flow lineto increase a pressure and a volume of the hydraulic liquid in the main flow lineby predetermined quantities, respectively.

Growing community of inventors

Chiba, Japan

Harutsugu Mizui