Patent GB-842359-A (GB)
Title: Hydraulic remote control steering systems
IPC: B63H25/28
Filed: 1956-09-03
Abstract: 842,359. Steering gear. MERCIER, J., and MERCIER, B. Sept. 3, 1956 [June 27, 1956], No. 26913/56. Class 114. [Also in Group XXIX] A hydraulic remote control steering system for ships has duplicated parts that function independently of each other and are brought into operation successively and automatically. In one embodiment, a rotatable control member 10, Fig. 2a, is mounted coaxially with a pivotal mounting of a lever 53 and has a driving connection (not shown) with a hydraulic pump 26 the casing of which is anchored to the lever so that, as in Specification 800,391, the resistance to turning of the pump causes the casing to react on the lever which is deflected to operate, in succession, valves 31, 33. The valve 31 controls the passage of liquid from the pump 26 to motors 32, 37 acting on the controlled member so that the latter moves in correspondence with the movements of the control member 10. The valve 33 controls the application of pressure from an indepen dent source 34 to an additional motor 35 to provide power assistance. When the pressure from the source 34 exceeds a predetermined value it urges a spring-loaded valve 36 to the position shown in which the two ends of the motor 32 are interconnected so that the controlled member is actuated in one direction by pressure acting on the difference in area of the two sides of the piston of the motor 32 and in the other direction by pressure on the motor 37. On failure of the source of pressure 34 the valve 36 connects the lower part of the motor 32 with the motor 37 so as to increase the volume of fluid necessary to actuate the controlled member a given amount. In a modification, the valve 36 and motor 37 are omitted and the independent source 34 may be replaced by a second pump 26 driven by the control member 10. In a further modification, the pump is driven by the control member through gearing and the control valves, provided with additional, direct actuating means, supply rotary motors connected to the controlled member. Fig. 4 illustrates another modification in which the two control valves 62, 64 control motors 66, 67 of which the pistons are connected to the controlled member 68 and the cylinders to a lever 69 which is operatively connected to valves 72, 74 controlling motors 73, 76 respectively and to the delivery controlling member of a pump 70 connected to a motor 71 which is connected, as are the motors 73, 76, to the controlled member 68. These motors are brought into operation successively as the deviation between the movements of the control and controlled members increases. A distributor controlling a constant delivery pump may be substituted for the pump 70. In a further modification, the pump 70 and motor 71 together with one of the valves 72 or 74 and its associated motor are omitted and a spring-loaded valve subject to the pressure of an independent source is provided so that when pressure is available from that source the valve 62 is connected only to the motor 66 whilst in the event of failure of that pressure the valve 62 is connected also to a motor which operates the controlled member. In another embodiment, the control member 100, Fig. 6, drives two pumps each with an associated valve 105, 106 connected respectively to motors 107, 108 and, through spring-loaded valves 121, 120 subject to the pressures in two independent pressure sources 116, 115, to motors 118, 117 actuating the controlled member 119. The motors 107, 108 act on a lever 109 which is connected through a floating lever assembly 110 to two control valves 111, 113, which communicate through the valves 120, 121 with the motors 117, 118. The arrangement is such that pressure from the sources 115, 116 urges the valves 120, 121 to positions in which they isolate the motors 117, 118 from the valves 105, 106 so that the motors are energized by the pressure sources, a link between the member 119 and the assembly 110 providing " followup ", but in the event of failure of one of the pressure sources the corresponding valve 120 or 121 connects the motor with which it is in communication with the corresponding valve 105 or 106 for direct actuation. The valve 111 is connected to the assembly 110 by resilient means to provide for staggered operation of the valves 111, 113. In a further arrangement, a control member 130, Fig. 7, delivers liquid to a " follow-up " cylinder 131 which actuates a lever 132 connected to valves 133, 134 whose operation is staggered. Each valve 133, 134 controls the connection of a corresponding pressure source 135, 136 with both of a pair of motors 139, 140 which drive the controlled member 137, a " follow-up " link 138 between the member 137 and lever 132 being provided.