GB588926A - Improvements in or relating to steering mechanisms - Google Patents

Abstract

588,926. Hydraulic systems ; ; steering ships &c. ARMANDIAS, L. S. (Soc. d'Inventions Aeronautiques et Mecaniques, S.I.A.M.). Sept. 13, 1944, No. 17509. [Classes 4 and 114] Rudders &c. are controlled by centring means fed by a continuously acting hydraulic pressure source and operating whenever the rudder is displaced from its-central position, together with hydraulically urged steering means also fed by a continuously acting source of hydraulic pressure and capable of applying a load in excess of the centring load for effecting the steering movements under control of a valve device, itself controlled by an operator. Pressure liquid from an hydro-pneumatic accumulator 25 flows through a reducing valve 23 to oppositely arranged cylinders 11, 16 containing free pistons 12, 17. against which abut the ends of a control rod 5, geared to the rudder 1. Displacement of the rudder can only take place against the pressure of the liquid on one or other of the pistons 12, 17. To effect steering movements, the liquid from the accumulator 25 acts directly through a manually-operated control valve 37 on one or other of two pistons 31, 32 in cylinders 33, 34, the pistons being connected to opposite ends of the tiller 26 and overcomes the restoring effect of the pistons 12, 17. Both circuits discharge into a common reservoir 79 from which a pump 75 returns the liquid to the accumulator 25, pressure being maintained in the centring circuit by a sustaining valve 73. In a modification, the centring cylinders are formed as extensions of the steering cylinders and rods projecting from the pistons of the latter engage the pistons of the former. Specification 509,923 is referred to.