GB689682A - Stabilising or anti-rolling equipment, particularly for ships - Google Patents

Abstract

689,682. Automatic stabilizing systems. POLLOPAS PATENTS, Ltd. (Montrose-Oster, L. E. W.). Nov. 1, 1949 [Nov. 2, 1948], No. 28388/48. Class 38 (iv). [Also in Groups XXXIII and XXXVII] Relates to a stabilizing equipment for ships and the like of the type employing a movable weight. At the bottom of the hold of the ship are provided rails 3 and racks 8 mounted transversely to the direction of travel and position as far as possible below the centre of gravity. These parts may be installed on a surface the curvature of which allows truck 1 to be displaced on a nearly horizontal plane. The truck carries its electric traction motors and one or more motor-generator or converter groups for supplying the motors. Fixed to driving-wheels 2 are toothed wheels 4 intercoupled by pinions 5 mounted on a common shaft 6. The shaft is driven by pinion 51 which meshes with a cage 7 of a differential having toothed wheel 4<SP>1</SP> gearing with rack 8. Directcurrent traction motors 11, 11<SP>1</SP> rotate in opposite directions and drive the free shafts of the differential, so that inequality of the speeds of the motors causes movement of the truck. The motors are supplied from a Ward-Leonard Ilgner set comprising fly-wheel 12, generator 13, A.C. motor 14 fed from the power plant of the ship, and an exciter 15. The truck also carries regulating apparatus of the type described in Specification 689,681, [Group XXXIII]. The truck will move along the rails from one side to the other under the control of the regulating apparatus responsive to the factors influencing the rolling of the ship. It is arranged that the maximum stabilizing couple is obtained when the truck is still spaced from the end of its travel. If the truck over-runs it will engage buffers and remain stationary until the control responds to move the truck towards the opposite side. The truck is started by increasing the field excitation of one motor and decreasing that of the other, reversal being also effected through field control. A sudden change of the instantaneous value of the turning moment upon the ship due to the wave action causes a rapid alteration of the rate of acceleration of the truck and this produces a reactive force upon the rails which is of short duration and acts in a direction to counteract such sudden change. The stabilizing system may be applied to floating vessels in general, and to parts of vessels such as gun mountings.