Patent ID: 7493802

Claim:
A liquid type identification device which identifies a liquid to be measured belonging to a hydrocarbon-based liquid or an alcohol-based liquid, comprising: an identification sensor unit which faces a flow passage of the liquid to be measured, the identification sensor unit including a liquid type detection unit with indirect heating which includes a heating body and a temperature-sensitive body and including a liquid temperature detection unit which detects the temperature of the liquid to be measured; and an identification calculation unit which applies a single pulse voltage to the heating body of the liquid type detection unit with indirect heating so as to generate heat and identifies the liquid to be measured according to an output of a liquid type detection circuit formed by the temperature-sensitive body of the liquid type detection unit with indirect heating and the liquid temperature detection unit, wherein the identification calculation unit identifies the liquid to be measured according to a liquid-type-corresponding first voltage value and a liquid-type-corresponding second voltage value, the liquid-type-corresponding first voltage value corresponding to a difference between the initial temperature of the temperature-sensitive body and a first temperature thereof at a time point when a first time period has elapsed from the start of application of the single pulse, the liquid-type-corresponding second voltage value corresponding to a difference between the initial temperature of the temperature-sensitive body and a second temperature thereof at a time point when a second time period longer than the first time period has elapsed from the start of the application of the single pulse.