Title:
SUBMERGED PUMP DEVICE FOR LIQUEFIED GAS TANK AND CONTROL METHOD THEREOF
Document Type and Number:
Japanese Patent JP3279892
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To surely protect a pump rotational system, even when magnetic attraction force of an active thrust magnetic bearing is made controllable.
SOLUTION: In a submerged pump device for a liquefied gas tank having an active thrust magnetic bearing 61, an auxiliary ball bearing 58 is molted in a position impeding excessive movement of a pump shaft 50 to its perpendicular downward, further a protection device is provided, which has a control function forcedly interrupting a power source of the active thrust magnetic bearing 61 for avoiding excessive movement of the pump shaft 50 to its perpendicular upward in accordance with a displacement value detected by a gap detection sensor 64 detecting a distance δ0 of fine gap part between a balance disk 59 and a stationary part.
Inventors:
Akira Manabe
Hiroaki Yoda
Agatsuma Mitsuo
Koichi Morofuji
Hiroaki Yoda
Agatsuma Mitsuo
Koichi Morofuji
Application Number:
JP29388795A
Publication Date:
April 30, 2002
Filing Date:
November 13, 1995
Export Citation:
Assignee:
株式会社日立製作所
東京瓦斯株式会社
東京瓦斯株式会社
International Classes:
F04D15/00; F04D7/02; F04D13/08; F04D29/04; F04D29/046; F04D29/048; F16C32/04; (IPC1-7): F04D7/02; F04D13/08; F04D15/00; F04D29/04; F16C32/04
Domestic Patent References:
| JP7119680A | ||||
| JP2221697A | ||||
| JP57116931A | ||||
| JP285012U |
Attorney, Agent or Firm:
Katsuo Ogawa (2 outside)