Patent GB-191412048-A (GB)
IPC: G05D13/00
Abstract: 12,048. Vulcan Werke Hamburg und Stettin Akt.-Ges. March 3, [Convention date]. Fluid governors; fluid relays.-In a controlling system for turbines, internal-combustion engines, steam-engines, or other motors driving through hydraulic transmission gears of the Fottinger type, and in which the supply of motive fluid to the motor is controlled by a valve operated through pistons or plungers by the hydraulic pressure in the gears, the motor supply-valve is closed before the gear passing, out of action is emptied, and its re-opening is retarded. The valve 14, controlling the steam supply to the turbine 1, is operated by a servo-motor, steam admission to the cylinders 12, 13 of which is controlled by a slide valve 10 connected to the double piston 7, 8 working in cylinders 6, 6' communicating with the forward and reverse hydraulic transmission gears 2, 3 respectively. The cylinders 6<1>, 6 are fitted with outlet cocks 18, 19 respectively, which are coupled together and connected with the reversing lever 20 of the hydraulic gear. Adjustable throttling members 21, 22 are inserted in the pipes 4, 5. In the position shown, the forward gear 2 is in action. On moving the reversing lever to the position R, the cock 19 is closed and the cock 18 opened. The pressure in the cylinder 6<1> is thus at once released, and the spring 11 moves the slide valve 10 to the left to supply steam through pipes 15, 15' to cylinder 12 and close valve 14 before the gear 2 is emptied. Steam is now supplied to the turbine only by a by-pass 17, which may lead to a particular nozzle of the turbine. As the gear 3 fills, the pressure fluid can pass therefrom to the cylinder 6 only through the throttling member 22, so that the re-opening of the valve 14 is retarded. Waste steam leaves the chamber of the valve 10 by a pipe 16 leading to the exhaust space of the turbine. Specification 22751/13, [Class 69 (ii), Hydraulic presses &c] is referred to. The Specification as open to inspection under Sect. 91 (3) (a) contains also the following subject-matter. Whereas in marine installations, the gear has to transmit a wide range of load, the sensitiveness of the control device is made to correspond with the power transmitted by the gear by arranging the return spring 11 of the valve 10 to act through a lever device, or, when steam pressure is used to return the valve 10, by throttling the steam supply to such returning means, or by regulable oil brakes or other damping devices connected with this valve. Instead of the outlet cocks 18, 19 and the separate throttling members 21, 22, valves in the pipes 4, 5 are arranged to open a maximum aperture when the corresponding gear is emptying, and a minimum aperture when the gear is filling; or the pipes 4, 5 may be connected at a particular part of the gear casing, where the pressure variation lags suitably; or a small tank which must be filled by the water from the gear before it passes into the cylinders 6, 6<1> may be interposed in the pipes 4, 5; or, where a slide valve is used for controlling the main steam or other supply (instead of the valve 14), the required retardation may be obtained by the lap of this valve. The pistons 7, 8 may be operated by the difference of pressure at two points in the gear, instead of by the absolute pressure therein as shown. In this case, two pipes from two points of each circuit 2, 3 of the gear connect with each cylinder 6, 6<1>, one at each side of each piston 7, 8. This difference in pressure in constant and independent of the pressure in the " return " pump which fills the gear. A further by-pass to the valve 14 may be provided with a hand-controlled spring-closed valve, for obtaining temporarily, as at starting, a full steam supply to the motor. This subjectmatter does not appear in the Specification as accepted.