GB370051A - Improvements in and relating to recording apparatus specially applicable for recording depths and distances found by echo sounding - Google Patents

Abstract

370,051. Echo-sounding apparatus; recording-apparatus. CRACE, J. G. and ANTHONY, F. L., H.M.S. Osprey, Portland, Dorset. Jan. 3, 1931, No. 312. [Class 118 (ii).] An electrochemical recorder, particularly adapted for use in recording depths determined by the echo-sounding method, comprises a rotating record-carrying drum, a stylus carried on an arm attached to a carriage reciprocated by a chain and means for tilting the carriage through a small angle at the end of its travel so that the stylus may be lifted from the drum, and the carriage returned to its initial position by a spring. The drum 12 is rotated by gearing 14, 15 and the stylus 1 is attached to a carriage 2 traversed along a slotted shaft 3 by the engagement of a projection 6 on the carriage with a pin 5 secured to a continuously driven chain 4. When the carriage 2 reaches the right-hand end of its travel the shaft 3 is partly rotated by a cam 7, the projection 6 then becoming freed from the pin 5 and the carriage returned to its starting position by a spring 9 ; the stylus 1 is at the same time lifted from the drum 12. A rod 8 normally contacts with the stylus to complete the recording circuit. In a modification, the shaft 3 is not slotted and the rod 8 is rocked by the cam to tilt the carriage. A star wheel may be attached to the shaft driving the chain 4 and a spring engaging its teeth may make and break the circuit through the primary winding of a transformer the secondary of which is connected to the stylus 1, the whole arrangement forming a device for marking a scale on the record surface. Alternatively the scalemarking circuit may be controlled by a tuning fork energized electromagnetically each time a sound is emitted. When the timing marks are being made the stylus may be disconnected from the echo circuit. A brush may be carried on the carriage behind the stylus to supply the electrolyte to the record surface. In order that the same width of record may be used with different depths, the sound may be emitted at a certain interval before the stylus starts from its zero position. Five contacts may be spaced along the chain 4 and any one may be selected to cause the emission, thus giving readings for five different ranges of depth. These contacts are used in conjunction with a quick-acting switch for breaking the actual circuit. To obtain a first rough estimation, the whole apparatus is run at one-fifth its normal speed.