Improvements in or connected with Marine Signalling Apparatus.

Abstract

Abstract 11,333. Allen, F. T. Aug. 5. Locating subaqueous sounds; subaqueous sound signals.-In a subaqueous sound receiver, particularly of the kind in which a submerged rotatably-mounted receiving horn is used to determine the direction of the sound source, the horn is in communication with a resonance chamber which can be tuned. Fig. 1 shows a vertical tubular resonance chamber 3 ending in a horn 2 with a diaphragm 1, the tube and horn having a jacket 4, and the intermediate space being exhausted. The device is rotatably mounted in supports 11, the direction of the horn being indicated by a pointer 22 moving over a graduated disk 23, and can be raised or lowered at will. A piston 14 can be raised or lowered by a rack 13 so as to obtain the maximum effeet in the detecting microphone and telephone 17. The piston may be in the form of a sound-proof chamber containing the microphone 27, sound being conveyed to the diaphragm 26 through a horn 25, Fig. 8. The pressure at opposite sides of the diaphragm may be equalized through tubes 41, 42 containing a choking-device 43. In another form, the piston is used only for resonance adjustment, the microphone being mounted in a lateral chamber near the bottom of the resonance chamber, and tubes may be provided for the supply of air under pressure to the resonance and microphone chambers. Two devices as above described may be used to locate the source of sound. Modifications are described in which the horn does not rotate, the diaphragm 1 being carried by, or replaced by the skin of the ship's hull.

Inventors

• 👤 Frederick Thomas Allen

Bibliographic Details