Title:
ROCKING REDUCTION DEVICE FOR SHIP
Document Type and Number:
Japanese Patent JP3191142
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To effectively apply rocking reduction to rolling and pitching in a ship by placing at least two unit rocking reduction tanks in each of which a liq. column is formed in a communicating tube and a liq. is filled to form air pressure in the tank at the upper part at predetermined spaced intervals from the center of gravity of a hull.
SOLUTION: The bow 1a of a hull 1 is provided with a first unit rocking reduction tank 2a. A stern part 1b is provided with a second unit rocking reduction tank 2b. When a hull's natural frequency cycle is changed due to a cargo loaded state, etc., an EA-valve 5 is opened to reduce the pressure ΔH of an air pressure layer A, changing the natural frequency cycle of a a liq. L. Thus, a damping effect is obtained. Furthermore, placing at least two unit rocking reduction tanks at spaced intervals from the center of gravity of the hull depresses high rocking force with comparatively the small unit rocking reduction tanks. Especially, its effect is higher owing to long distance from the center of gravity when the unit rocking reduction tank is delivered to the bow part and the stern part, respectively.
Inventors:
Masayoshi Hirano
Motohiro Hineno
Motohiro Hineno
Application Number:
JP30326295A
Publication Date:
July 23, 2001
Filing Date:
October 18, 1995
Export Citation:
Assignee:
Akishima Research Center, Mitsui Shipbuilding Co., Ltd.
International Classes:
B63B39/03; (IPC1-7): B63B39/03
Domestic Patent References:
| JP1162894U | ||||
| JP491836B2 | ||||
| JP5145878B2 |
Attorney, Agent or Firm:
Shinichi Ogawa (2 outside)