Patent ID: 7254897

Claim:
A tilt sensor comprising: a printed circuit board disposed in a direction generally normal to a reference plane for measuring a tilt angle; a pair of electrodes formed on a first portion of the printed circuit board; a cover affixed to the printed circuit board and creating a cavity between the cover and the first surface of the printed circuit board, the cover being adjacent to the pair of electrodes with a gap between the cover and the pair of electrodes, the cover used as a common electrode for the pair of electrodes, the cover and the pair of electrodes defining a pair of capacitors; an inert liquid contained in the cavity, the surface level of the inert liquid varying according to the tilt angle of the reference plane; and, a signal processing circuit formed on a second portion of the printed circuit board, the signal processing circuit producing an output signal corresponding to a difference in capacitance between the two capacitors as a tilt angle detection output.