GB914997A - Device associated with the hull of a ship for utilizing pitching and rolling movements to propel the ship and dampen such movements - Google Patents

Abstract

914,997. Utilizing wave-energy. HALLEN, A. E. Nov. 10, 1959 [Nov. 12, 1958], No. 38136/59. Class 69 (1). In a device associated with the hull of a ship for utilizing the pitching and rolling movements to propel the ship and dampen such movements the device consisting of rudderlike flappers 1 disposed below the water-line of the ship and mounted for swinging movement on horizontal shafts 2 extending at rightangles to the longitudinal axis of the ship, the flappers are acted upon by spring means 7 biasing the flappers 1 to substantially horizontal positions. As shown in Fig. 6, lever arms 6 are secured to a shaft 2 and are articulated to spirally-wound spring devices 7 (Fig. 7). In a modification shown in Fig. 9, the arms 6 are replaced by toothed segments 8 in engagement with racks 9. In a further modification, a beam 11 (Fig. 10), may be provided to support bearings for flappers 1a. The shaft 2 may act as a torsion spring. Each flapper may be divided into a plurality of flappers 1b (Fig. 11). In the modification shown in Fig. 12, an air spring is provided comprising pistons 18 moving in a cylinder 17 containing oil which is forced upwardly into an air tank 20 during movements of the flappers 1. A shut-off valve 22 is provided to prevent movements of the pistons 18 and thereby lock the flappers in horizontal positions.