Patent GB-442125-A (GB)
Title: Improvements in or relating to torpedoes without visible wake
IPC: F42B19/14
Filed: 1934-04-27
Abstract: 442,125. Torpedoes. VICINO, S. DI, 301, Via Posillipo, and ENRIETTI, M., 169, Via Tasso, both in Naples, Italy. April 27, 1934, Nos. 12833, 12834, and 12835. Void [Abridged as open to inspection under Sect. 91 of the Acts, Oct. 30, 1934]. [Class 9 (ii)] [See also Groups XXVI and XXIX] Torpedoes are propelled by means of ammonia or other substance capable of dissolving in the water so as to leave no trace of the passage of the torpedo. The ammonia is stored in the torpedo in the liquid state and is evaporated by an internal source of heat or by the heat of the surrounding water. It drives the torpedo by means of a turbine or a reciprocating motor or by jet reaction. In the form shown in Fig. 1, ammonia stored in a tank 1 is allowed to flow into a surrounding chamber 3 through a valve 7 controlled by a float 8. The walls of the chamber 3 are exposed to the water, the heat from which vaporizes the ammonia. The vapours pass through a pipe 11 to turbines 12 and thence through a pipe 13 to the hollow propeller shaft 19, which is driven from the turbine by gearing 15, 15a. The propeller shaft has an enlargement containing a valve plug 18, normally held closed (as shown) by a spring 25 to prevent inflow of water before the torpedo has acquired sufficient speed. The initial rotation of the turbine operates gearing 34, 35, which, after a certain number of revolutions, unscrews and releases a valve 33a, whereupon ammonia vapour is admitted behind a piston 23 and pushes the valve 18 to the open position. When the supply of ammonia is exhausted, the valve returns to the closed position, and the torpedo floats and may be recovered as required in practice runs. In warfare, it is desirable to sink the torpedo at the end of its run if it has not exploded; for this purpose, a spring catch 37 is provided to engage with a notch 38 in the piston rod 21 to retain the valve 18 open, so that water can enter the torpedo and sink it. The loss of weight by the evaporation of the ammonia during a run is counterbalanced more or less as desired by the admission of water into a space 1b behind a piston 10 in the ammonia tank 1. This piston is driven by a screw 40 operated by the turbine 12 through a reducing gearing 43, which is set according to the counterbalance desired. In another form, the torpedo is started by a jet of compressed air and then propelled by a jet of the ammonia, a small ammonia driven turbine being provided to drive the screw 40, its exhaust being at the edge of the main propelling jet. Valves are provided to keep off the ammonia until the compressed air has exhausted itself and to prevent entry of water when the ammonia is exhausted. The propelling nozzle comprises a chamber followed by a constriction leading to an expanding conical outlet. The orifice of the outlet is provided with a closing plug which is partially unscrewed by the launching of the torpedo and further unscrewed and blown off by the compressed air. In another form, Fig. 3, the ammonia is pumped from its tank 1a by a pipe 89 and a pump 87, and is forced by a pipe 88 through a spiral passage 85 to a chamber 3b around part of the tank 1a, and thence through holes 83 back into the tank, from which it passes through a valve 7 to a chamber 3a in prolongation of the chamber 3b and containing floats for controlling the valve 7. The spiral passage 85 is in contact with the external water, and the vaporized ammonia collects in the chamber 3a and is taken therefrom by a pipe 80 to a reciprocating motor 81 for propelling the torpedo. The exhaust is into a chamber 100 and thence through a non- return valve 102 to the hollow propeller shaft 101. In this form, moreover, two pistons 10a, 10b are moved in opposite directions by the screw 40 to admit water at both ends of the ammonia tank. In still another form, the spiral passages 85 are arranged directly around the ammonia tank, the chamber 3b is dispensed with, and the chamber 3a replaced by a chamber between the tank and the pump. The reciprocating motor is replaced by a turbine and the exhaust is into a chamber containing water which is continuously pumped in and out, the ammonia being absorbed by this water.