GB912573A - Improvements in or relating to control equipment for the steering means of motor boats and motor ships - Google Patents

Abstract

912,573. Automatic ship-steering control. WALKER & SON Ltd., THOMAS. June 29, 1961 [June 30, 1960], No. 22932/60. Class 38 (4). [Also in Group XXXIII] In a ship's automatic pilot, electrical signals derived from a compass control the steering gear through a pneumatic actuator utilizing a pressure below atmospheric derived from an internal-combustion engine propelling the ship. In Fig. 1 a ship's magnetic compass rotor 16 has transparent and opaque sectors 22, 23 so that if the course of the ship deviates in one sense from a heading determined by the setting of a photo-cell and lamp 18, 19, a solenoid 25 is energized through a relay 40 to move a pneumatic valve 27 to the position shown and thereby connect the underside of piston 44 of a pneumatic actuator 42 to a chamber 72 maintained at a pressure below atmospheric, so that the ship's steering wheel 13 is moved anti-clockwise to correct the course. De-energization of solenoid 25 when the ship deviates from course in the opposite sense allows valve 27 to fall under gravity and connect the upper side of piston 44 to chamber 72 so that the steering wheel is moved in the opposite sense. Alternatively, piston 44 may be moved in the opposite sense by a spring. The pressure in chamber 72 is maintained below atmospheric by its connection through a non-return valve 54 to the crankcase or induction manifold of a two-stroke or four-stroke internal-combustion engine 12, propelling the ship. The steering wheel may adjust the position of an outboard motor, or actuator 42 may operate an auxiliary rudder directly. Compass rotor 16 is provided with adjustable limit stops (not shown).