Stress level measuring device

Claim 1

A stress level measuring instrument comprising: (a) first calculating means for continuously calculating a mean pulse frequency per unit time from a cycle time of a unit of pulse signals detected by a pulse detector, (b) second means for deciding a basic pulse frequency wherein a value of said mean pulse frequency obtained by said first calculating means is compared with a succeeding value of said mean pulse frequency, a lower value of said means pulse frequency being stored temporarily in a memory as a tentative lowest value of said mean pulse frequency, said tentative lowest value of said mean pulse frequency being replaced every time a new lower value of said mean pulse frequency appears, said tentative lowest value of said mean pulse frequency being finally determined to be a basic pulse frequency measured for a day, (c) third means for replacing a lowest limit value of said basic pulse frequency wherein a value of said basic pulse frequency obtained by said second means is compared with a lowest limit value of said basic pulse frequency measured over a long term period before said day of determining said basic pulse frequency of said day, said lowest limit value being replaced when a value of said basic pulse frequency measured for said day is less than said lowest limit value of said basic pulse frequency measured over said long term period, (d) second calculating means for calculating a stress level wherein a value obtained by subtracting said lowest limit value of said basic pulse frequency measured over said long term period from a value of said basic pulse frequency measured for said day is stored as said stress level, and (e) fourth means for displaying a stress level wherein said stress level obtained by said second calculating means is displayed with a series of stress levels measured in a past predetermined period.