| 摘要 |
PURPOSE:To provide a simple and compact device for adjusting rotary inertia by connecting a small rotor rotated with high speed to a pump rotor through a reduction gear to add large rotary inertia to a pump for loosening pump coast- down. CONSTITUTION:A rotor 5 having a small moment of inertia compared with that of a pump rotor is rotated with high speed compared with that of the pump rotor. And, in pump trip or the like, when large rotary inertia is required, the rotational frequency of the rotor 5 is once dropped approximately to that of the pump rotor by a reduction gear 7 and then the rotor 5 is connected to the pump roter. Thus, the weight of the pump rotor can be reduced and the load on a thrust bearing 6 can be reduced. Also, a compact device can be provided as a whole so that it is advantageously arranged with excellent economy. Since the rotary inertia of a pump body 1 can be reduced, the rotational frequency can be quickly changed. |
