Patent attributes
Capacitive liquid condition sensing apparatus includes a pair of a 1-1 electrode and a 1-2 electrode arranged to form a first capacitance; a pair of a 2-1 electrode and a 2-2 electrode arranged to form a second capacitance; a circuit board formed with a sensing circuit to sense the liquid condition such as a liquid level in accordance with the first and second capacitances; and 1-1, 1-2, 2-1 and 2-2 conductive paths connecting the 1-1, 1-2, 2-1 and 2-2 electrodes, respectively, to the sensing circuit, and including 1-1, 1-2, 2-1 and 2-2 conductive segments, respectively. The 1-1, 1-2, 2-1 and 2-2 conductive segments are arranged in a row, and extend side by side. The 1-1, 1-2, 2-1 and 2-2 conductive segments are arranged so that a first parasitic capacitance formed between the 1-1 conductive segment and the 1-2 conductive segment is equal to a second parasitic capacitance formed between the 2-1 conductive segment and the 2-2 conductive segment.
