| 摘要 |
<p>PROBLEM TO BE SOLVED: To disclose a control method for the hydraulic chuck of a rotary machine tool for fastening a work to be machined, to be operated by a double acting fastening/loosening actuator. SOLUTION: When fastening pressure to be controlled based on a set point for fastening pressure is applied at least to one chamber of an actuator 20, and when pressure is abruptly lowered just because of the failure in control pressure of the actuator 20 at the upstream, pressure is maintained by a pressure corresponding chamber. Fastening pressure is controlled by means of a closed loop, and furthermore, fastening pressure within the chamber is corrected, and the maintenance of pressure of the specified period of time is nullified by the request of an operator correcting fastening pressure applied to a work. The period of time for nullification is at least equivalent to the time required by the pressure stabilization of a control system.</p> |
