Patent ID: 8230728

Claim:
An alcohol concentration sensor for detecting an alcohol concentration in mixture fuel composed of petroleum-fuel and alcohol, the alcohol concentration sensor comprising: electrodes immersed in the mixture fuel contained in a fuel tank of an automotive vehicle; a conductor portion including a first conductor portion and a second conductor portion, the first conductor portion being integrally formed with the electrodes; and a casing disposed in the fuel tank, the casing containing the electrodes and the first conductor portion, wherein: the first conductor portion is disposed in the casing and is led out of the casing to an inner space of the fuel tank and the second conductor portion extends from the first conductor portion, through the inner space of the fuel tank, and extends to an outside of the fuel tank, so that the conductor portion extends continuously as a one-piece conductor without connectors or junctions from the integral formation with the electrodes to the outside of the fuel tank, and the entire conductor portion, including each of the first conductor portion and the second conductor portion, is a bare conductor that is not covered with an insulating layer.