| 摘要 |
A hydraulic servo drive device includes: a pilot spool (20) for switching supply and shutoff of oil; a servo piston (11) slid in accordance with the pilot spool (20); a stroke sensor (15) for detecting a displacement of the servo piston (11); a first hydraulic chamber (51) in which oil for moving the servo piston (11) is flowed; a first piston oil path (65) for communicating a pump port to which oil is supplied from a pump with a first hydraulic chamber (51); and a discharge circulating oil path (66) for communicating the first hydraulic chamber (51) with a drain port. |
