GB980651A - Automatic hovering gear for submarines - Google Patents

Abstract

980,651. Valves. HARLAND ENGINEERING CO. Ltd. Aug. 29, 1962, No. 33178/62. Heading F2V. [Also in Divisions B7 and G3] The buoyancy of a submarine is controlled by filling and emptying a tank 4, Fig. 1, which is connected to an external tank 2 with a vent 3 by a pipe 16 containing a pump 12, a pressureactuated valve 17, a distributing valve 7, a pipe 8, and a hover valve 9; the valve 17 controls flow in a pipe 18 opening into the tank 4. The apparatus functions when depth can no longer be maintained by the normal hydroplanes. The valve 7, Fig. 2, is a double-landed piston 32 with a through bore 42 which is connected via a duct 44 to the pipe 18, the piston controlling ports 37, 38 and 39. The valve 17 consists of two pistons 55, 65 the latter having double the effective area of the former, each piston having a stop 56, 66 whilst a spring 67 is disposed between the pistons. The space 41 between the pistons leads to the lower set of distributing ports 39; the upper piston 55 controls ports 63 leading to the pipe 18. The piston 55 is open to the pressure in the line 16 and the space below piston 65 is connected to the pipe 8 through a restriction. Upon lifting the piston closure 32, the pump output is directed through ports 37 and 38 to the pipe 8. When the closure 32 is lowered the ports 37 closed and water flows from the tank 2 via ports 38, 39 to space 41, the pressure in pipe 16 lowering piston 55 and enabling the pump output to flow through ports 53 into space 41. The pressure in the latter lowers the piston 65 to open ports 63 whereby all the fluid in space 41 is discharged into pipe 18. The valve is controlled by means responsive to the depth error of the submarine and vertical velocity and acceleration, the error detecting means consisting of a ball valve 88 opened by an adjustable spring 96, loading of which is set for a desired depth, and opposed by a bellows 97 detecting actual depth by hydrostatic pressure. The ball valve 88 controls the flow into lines 101, 102, 103 a depth gauge 105 being connected to line 101; each line opens through a throttle 127 into a chamber 126 of a separate one of three servo-devices A, B, C, arranged in cascade, the last device C actuating the valve 7. The servo-devices are identical, each comprising a pilot valve 125 operated by the pressure in chamber 126 and controlling movement of a piston 114 in a cylinder connected by a duct 136 to the chamber 126 of the next device, from which chamber the fluid escapes via the associated throttle; the fluid connections of the last device C are slightly different as shown. A lever 113 and spring 111 provide a " feedback " between each piston 114 and pilot valve 125. An accumulator 160 is connected to each chamber 126 to smooth out the effect of wave motion. The pilot valves and " feedback " mechanisms are rotated to minimize friction through gearing driven by the electric motor 86 driving the supply pump 82. The fluid in the system is heated by thermostatically controlled heaters 170, 171.