Patent ID: 6442855
Filing Date: 2002-09-03
Classification: G01C

Abstract:
A tilt sensor comprising:a printed circuit board disposed in a direction normal to a reference plane for measuring a tilt angle; a pair of differential electrodes mounted on the printed circuit board; a common electrode plate opposed to the pair of differential electrodes with a predetermined gap formed between said differential electrodes; a common electrode fixed to the printed circuit board by a terminal formed from the common electrode plate; a dielectric liquid filled into a closed space in a state where its surface level varies according to the tilt angle of the reference plane; a signal processing circuit section formed on the printed circuit board, said signal processing circuit section producing an output signal corresponding to a difference in capacity between two capacitors, each capacitor includes the common electrode and a respective differential electrode of said pair of differential electrodes, as a tilt angle detection output, wherein the pair of differential electrodes are mounted electrically independently of each other in upper and lower regions respectively, wherein said upper and lower regions are divided by a horizontal centerline, said horizontal centerline passing through a center of gravity of said printed circuit board in a direction normal to a direction of gravity when said printed circuit board is in a no tilt condition, and said pair of differential electrodes are formed in shapes symmetrical to said horizontal centerline and a vertical centerline of said printed circuit board, said vertical centerline passing through said center of gravity and normal to said horizontal centerline; and an oil case for storing the pair of differential electrodes and the common electrode plate and forming said closed space between itself and the printed circuit board.