Patent GB-191113415-A (GB)
Title: Improvements in Fluid-pressure Apparatus for Operating Bulkhead and other Doors.
Inventor: PIKE FREDERIC JOHN
IPC: B63B19/00
Filed: 1911-06-03
Granted: 1912-05-30
Abstract: 13,415. Pike, F. J., and Neville, H. June 3. Operating sliding doors.-- In a reversible two - main hydraulic system for operating ships' bulkhead or other doors either individually by means of a local door valve or simultaneously from a distant point such as the bridge, or automatically on the rise of water in a compartment, the local valve is provided with a non-return valve which, when closed, prevents opening of the door from the bridge by preventing the flow of pressure fluid to, or exhaust from, the door cylinder, but which in no circumstances prevents simultaneous closing from the bridge. The " opening " main 1, Fig. 1, that is, the pressure main for simultaneously opening the doors, and the " closing " main 2 are alternately placed in communication with pressure pumps and an exhaust tank by the reversal of a known kind of bridge valve 5 comprising a slide valve 9 operated by fluid pressure controlled by a pilot valve 25 actuated by a lever 31 and wire 35. The local valve shown in section in Fig. 2, is connected to the mains 1, 2 by the passages 51<a>, 52<a>, and to the opening and closing ends of the door cylinder by the passages 49<a>, 48", and comprises a pair of double-beat valves 57, 58 normally held in the position shown by springs 57<k>, 58<k>, so that free communication exists between the main 1 and passage 49<a> through the lower seating of valve 57 and passage 60, and between main 2 and passage 48<a> through the upper seating of valve 58 and passage 59. The bridge control may be temporarily reversed locally on reversing the valves 57, 58 against the springs 57<k>, 58<k>, by raising a lever 61 engaging the ends of the valve spindles. The non-return valve 93 for eliminating opening of the door from the bridge is shown as normally held open against the action of a spring 95 by means of a cam 96 operated by or formed integral with the valve lever 61 and adapted when closed to prevent exhaust from the closing end of the door cylinder through passage 48<a>. The valve 93 is allowed to close by lowering the lever 61 beyond its normal position on removing a pin 61<a>. The non-return valve 93 may be arranged in the passage 51<a> to prevent the flow of pressure fluid to the opening end of the door cylinder or may be arranged in any other suitable position between the passages 51<a> and 49<a> or between passages 52<a> and 48<a>. The non-return valve 93 may be normally closed to permanently eliminate opening of the door from the bridge, by forming the cam 96 as shown in dotted lines 96<a> in Fig. 2, in which case the valve 93 may be opened, without reversing the valves 57, 58, by means of the right-hand portion of the cam when the lever 61 is depressed, and is also opened during the act of reversing the door valve, by means of the left-hand portion of the cam. Instead of springs 58<k>, 57<k>, the valves 58, 57 may be returned to normal position by weights or fluid pressure acting on pistons attached to the valve stems, or one stem only may be subjected to the returning force. In a modified construction of door valve, the valves 57, 58 are arranged upon the same side of the pivot of the valve lever 61 and both rise or fall together, fluid pressure being employed to return the valves to normal position. In a further modification, the valves 57, 58 are replaced by a single slide valve, which is kept against its seat by fluid pressure acting upon a portion of the back of the valve. The bilgecontrol arrangement comprises a plunger 66, Fig. 2, exposed to the pressure in the passage 51<a> and normally held in the raised position by a cam or detent 68 on a spring-controlled lever 71 connected by a wire 56 to a float in the bilge. On an abnormal rise of water, the float rises and pulls the wire 56 releasing the plunger 66, which is then depressed by the fluid pressure and acts upon the end of the lever 61, reversing the valves 57, 58 to close the door. By omitting the plunger 66, non-return valve 93, and parts relating thereto, either of the forms of door valve may be used as a bridge valve instead of the valve 5.