PURPOSE: To reduce the driving force of switching valves for flow adjustment in a passive anti-rolling tank and facilitate the adjustment in response to the natural rolling cycle of each ship.
CONSTITUTION: In a passive anti-rolling tank T communicated with side tanks 2S, 2P arranged on both sides of a hull via ducts 3, both side tanks 2S, 2P are practically communicated via multiple ducts 3F, 3A, and controllable switching valves 4 are provided in the ducts 3F, 3A. The flow cycle of the whole water moved via multiple ducts 3F, 3A is controlled by the switching control, either one of multiple ducts 3F, 3A is controlled to reduce the valve switching power, and the phase difference in each cycle of rolling is detected to control the total flow for the anti-rolling action.
SUZUKI SHINICHIRO