Miniaturized automatic decompression computer

Claim 1

A decompression meter for use in diving excursions which comprises, a. ambient pressure-sensing means including an ambient-pressure gas chamber; b. computer means comprising a time-constant gas chamber having a pressure port and a gas diffusion membrane separating the time-constant gas chamber from the ambient-pressure gas chamber for measuring continuously the uptake and release of gas of human tissues under fluctuating hyperbaric ambient pressures; and, c. indicator means including a gauge operatively associated with the computer means for indicating the appropriate decompression schedule in terms of hyperbaric pressures and time intervals, said gauge including an indicator and a mechanical assembly operative to actuate the indicator in response to fluctuation in gas pressure in the time-constant gas chamber comprising, 1. pressure-responsive means comprising a resilient diaphragm fluid-tightly closing the time-constant gas chamber pressure port and a piston for reciprocating motion toward and away from the time-constant gas chamber in response to changes in gas pressure in the time-constant gas chamber, 2. gear means including a pinion gear fixed to the indicator and a rack in driving engagement with the pinion gear, 3. lever means in driving engagement with the rack and driven engagement with the pressure-responsive means.