초록 ▼

An interval timer circuit includes an RC circuit selectively coupled to a reference voltage source such that when power is removed, the capacitor discharges in a predictable manner to provide a time dependent but power supply independent voltage across the capacitor which can be employed to determin

An interval timer circuit includes an RC circuit selectively coupled to a reference voltage source such that when power is removed, the capacitor discharges in a predictable manner to provide a time dependent but power supply independent voltage across the capacitor which can be employed to determine the downtime of electrical equipment or machinery.

대표청구항 ▼

An interval timer for use in providing a time-related output voltage used for determining the downtime of an aircraft engine, said interval timer comprising: a direct current reference voltage source; a capacitor and resistor coupled in parallel relationship to each other, said capacitor and said re

An interval timer for use in providing a time-related output voltage used for determining the downtime of an aircraft engine, said interval timer comprising: a direct current reference voltage source; a capacitor and resistor coupled in parallel relationship to each other, said capacitor and said resistor having values for providing a relatively high RC time constant; means for selectively coupling said reference voltage source to said capacitor such that said capacitor will have charged to a predetermined voltage when the aircraft engine is shut down and said charged voltage will reduce from said predtermined voltage with shutdown time of the engine in a predictable manner allowing the voltage to be subsequently measured to determine the engine downtime; and means coupled to said capacitor for monitoring the voltage across said capacitor to determine the downtime of the engine as represented by the reduced voltage across said capacitor upon restarting of the engine.