Electronic device to record temperatures and the time of occurrence

A digital min-max thermometer that comprises, in combination:

• temperature transducer means for periodically sensing the temperature in the surrounding environment and for providing a signal representative of that temperature;
• time keeping means to provide the corresponding time of occurrence of the temperature thus sensed;
• storage means for storing previously attained minimum and maximum values of temperature and the time of occurrence thereof;
• means for comparing the most recently sensed temperature with stored values of temperature for a limited subinterval of time to find local minimum and maximum temperatures for that subinterval, there being a set of contiguous subintervals that together form a major time interval, minimum and maximum temperatures and corresponding times of occurrence for each said set being stored;
• means for reviewing the stored minimum and maximum temperatures of each set of contiguous subintervals to find the greatest and least temperatures recorded during the most recent major time interval terminating at the time of review and the times of occurrence thereof;
• and means for displaying the most extreme temperatures for said major time interval together with the time of occurrence of each such extreme.