Method and apparatus for determination and display of gas consumption time
US4970897A · kind A · utility
Inventor
Key dates
| Filing date | Dec 8, 1989 |
| Grant date | Nov 20, 1990 |
| Priority date | — |
| Expiry date | Dec 8, 2009 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF17C2270/0781
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A portable, battery powered apparatus is provided for determining and displaying the amount of time that a fixed supply of breathable gas can sustain a consumer who wishes to breathe the gas at one or more ambient pressures. The apparatus include a device for measuring the ambient pressure in the vicinity of the consumer at least once every ten second and for generating signals representative of the ambient pressure. A device is provided for measuring the pressure of the supply gas and for generating signals representative of the supply gas pressure. The apparatus preferably includes a programmed microprocessor which periodically receives a series of supply gas pressure measurement signals and periodically determines from the series of supply gas pressure measurement signals the average rate at which the supply gas was consumed (Consumption Rate) over a time at least five times as long as the average time between the supply gas pressure measurements. A normalized Consumption Rate is determined by normalizing each determined Consumption Rate to compensate for the ambient pressure on the consumer during the time period over which the Consumption Rate was determined. A normalized Cons…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.