| 摘要 |
PURPOSE:To prevent the fracture of a single crystal owing to the oscillation in the event of an earthquake, etc. by controlling an actuator by the output signals from acceleration detectors and suppressing the acceleration to be applied to a main body to a min. level. CONSTITUTION:The displacement signals or acceleration signals of the main body 3 or a supporting part 4 integral with the body 3 are inputted to a control part 9 from the acceleration detectors 11, 12 installed to the body 3 and a displacement detector 10 for detecting the relative displacement between the supporting part 4 and an outside foundation, i.e., a rail 5 when the earthquake arises. The control part 9 operates the actuator 8 so as to decrease the acceleration and displacement of the body 3 thereby acting the force separate from the seismic power to the body 3 or the part 4. Since a drawback movement and attenuation effecting part 7 is also installed to the part 4 for the body 3, the proper drawback force and attenuation force are acted to the body 3 or part 4 by said part, by which the exertion of the seismic power to the device for pulling up the single crystal is effectively prevented cooperatively with the actuator. |
