Wrist-worm rate of ascent/descent indicator
US5103685A · kind A · utility
Inventor
Key dates
| Filing date | Oct 16, 1990 |
| Grant date | Apr 14, 1992 |
| Priority date | — |
| Expiry date | Oct 16, 2010 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB63C2011/021
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A wrist-worn, real-time-indicating, actual rate of ascent/decent meter includes a non-corrodable, hermetic enclosure with a window. A display, visible through the window, includes numeric rate-related indicia and arrows, both clearly visible against a contrasting backdrop. The contrast may be black on silver. A hysterisis-free transducer in the enclosure produces first signals proportional to the ambient pressure. The first signals are converted to second signals representing depth in the ambient, the latter signals being periodically sampled. Each sample is compared to the previous sample and third rate-of-change-of-depth-with-time signals result from successive comparisons. The third signals are displayed numerically and direction (ascending or descending) is indicated by the arrows. Signal processing is controlled and performed by a microprocessor within the enclosure. Facilities are provided to replace a battery and to turn the meter on and off without affecting the hermeticity of the enclosure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.