GB1123377A - Apparatus for stabilizing the roll of a ship - Google Patents

Abstract

1,123,377. Ship stabilizers. VOSPER Ltd. 25 Jan., 1967 [30 Oct., 1965], No. 46022/65. Heading B7M. Apparatus for stabilizing a ship, or other buoyant vessel, when rolling comprises a truck or trolley 10 mounted on rails 11 that are orientated athwartships and provided with stops 26 at either end, reciprocation of the truck being effected by a plurality of swash-plate hydraulic motors 12 therein that are connected in parallel to an hydraulic accumulator 13 and a piston-and-cylinder unit 14 (as shown in Fig. 2), which unit contains a pair of rams 25 that may engage with one or other of the stops 26 whenever the truck approaches either end of the rails, the motor being controlled by roll-sensing means 9 situated externally of the truck. In operation, rolling of the ship from an upright position in either direction causes actuation of servomotors (not shown) by the means 9, which motors effect appropriate operation of the motors 12, the latter being caused to operate as pumps when retardation of the truck is necessary as it approaches either of the stops 26. When operating as pumps, the motors 12 displace hydraulic fluid from the unit 14 into the accumulator 13, the fluid stored in the accumulator being subsequently returned to the unit 14 through the motors when the latter resume their driving action. The hydraulic system associated with the motors 12 also includes a source of hydraulic fluid 20, a pump 21, a second hydraulic accumulator 19, a second pump 16, a heat-exchanger 15 for cooling said fluid, a non- return valve 17, a pressure-relief valve 30, and a volume-trimming valve 18. Alternatively, the motors 12 are situated externally of the truck 10 and are connected thereto by wire ropes (32), Fig. 3 (not shown). Retardation of the truck as it approaches the end of each traverse of the ship may be partially effected by upward curvature of the ends of the rails 11. The unit 14 may be replaced by a buffer or ram (25) and an associated piston- and-cylinder unit situated at each end of the rails 11 in place of the stops 26.