Perishable good integrity indicator
US5442669A · kind A · utility
Inventor
Key dates
| Filing date | Dec 27, 1993 |
| Grant date | Aug 15, 1995 |
| Priority date | — |
| Expiry date | Dec 27, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG07C3/04
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A perishable good integrity indicator includes a first oscillator for outputting a first clock signal which does not substantially vary in response to temperature. A second oscillator outputs a second clock temperature which varies as a function of temperature. A counter counts the pulses of the second clock signal during a time period determined by the first clock and outputs a count value. A data table receives the count value, translates the count value into a time temperature value representing the relationship of time and temperature during the time period and outputs the time temperature value to an adder. The adder adds the time temperature values output by the data table over time and outputs a cumulative time temperature value corresponding to shelf life for a product.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.