Accession Number : ADD012027

Title :   Shallow Depth Lead Weight Ejection Circuit.

Descriptive Note : Patent,

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON DC

Personal Author(s) : Coleman,Jeffrey L

Report Date : 15 Jan 1985

Pagination or Media Count : 8

Abstract : The invention is a safety circuit for torpedoes which causes lead weights to be ejected when the torpedo is not running and is below a predetermined depth. It uses a COMOS multivibrator and NAND gates to pulse power to the existing pressure transducer and a comparator. This comparator checks depth and alternator power. When conditions are met, it holds power on and after five seconds, causes the weights to be dropped. The circuit is powered by existing batteries in the torpedo exercise head. To minimize any effect on the battery life, a strobbing technique is used where voltage is switched on for only a few milliconds once every ten seconds. Depth is checked by the use of the comparator. One comparator input is connected to the torpedo's depth transducer and the other to a reference voltage in accordance with the predetermined depth limit. When the transducer voltage exceeds the reference voltage, the comparator turns on. One output from the comparator then latches-on for as long as the comparator is on. A second output from the comparator controls the lead weight dump switch. The output is inhibited from turning on the dump switch for five seconds after the comparator activates by a series pass transistor. Following a valid five second period the dump relay switch releases the lead weights. (Author)

Descriptors :   *PATENTS, *TORPEDOES, *EXERCISE HEADS, *SAFETY EQUIPMENT, *PRESSURE TRANSDUCERS, TORPEDO COMPONENTS, COMPARATORS, MULTIVIBRATORS, NAND GATES, LIFE EXPECTANCY(SERVICE LIFE), ALTERNATORS, TRANSDUCERS, ELECTRIC BATTERIES, LIMITATIONS, VOLTAGE, CIRCUITS, PULSES, INVENTIONS, OUTPUT, CONTROL, POWER, DEPTH

Subject Categories : Safety Engineering
      Torpedoes

Distribution Statement : APPROVED FOR PUBLIC RELEASE