| 摘要 |
PURPOSE:In a device for driving a servo valve with a force motor employing a flame-retarding working fluid such as a water-glycol mixture, to prevent the burnout of the motor, by making minute the electricity supply to the motor. CONSTITUTION:In an embodiment as a servomechanism driver for a vibrator 1, a servo valve is composed of a slave valve 2 and a pilot valve 3. The pilot valve 3 is driven by a force motor 4. The motor 4 is controlled by an input section comprising a signal generator 5, adders 6, 8 gain setting units 7, 9, a clip circuit 10 and a servoamplifier 11. The outputs of displacement detectors 12, 14 for the vibrator 1 and the slave valve 2 are fed back to the adders 6, 8. The clip circuit 10 comprises a relay 20 which is energized when a pump for supplying working oil is stopped, a contact 21 which is closed by the energizing of the relay, an operational amplifier 17 and so forth. When the contact 21 is closed, an output signal e0 has a minute value. |
