| 摘要 |
PURPOSE:To detect the acceleration in the directions of three axes with a single sensor by supporting a weight in square plate of poly Si for forming Z-axis movable electrode between the Si substrate of X/Y-axis surfaces and the upper electrode plate of poly Si which becomes the fixed electrode of Z axis with the beam of each corner and then converting the displacement in weight to the increase/decrease in the electrostatic capacity between the electrodes. CONSTITUTION:When an acceleration in X-axis direction is applied to a weight 31, a beam 34 is deflected in X-axis direction with the support point at the other edge part as a support, the weight 31 is displaced in X-axis direction and the electrostatic capacity between a movable electrode 32X and a fixed electrode 35X increases, and the electrostatic capacity between the electrodes 32X and 36X decreases. The amount of change of the electrostatic capacity is taken between terminals S0 and SX1 and between terminals S0 and SX2, thus detecting the acceleration in X-axis direction. Also, in a similar manner. the amount of change in the electrostatic electricity due to the application of acceleration in Y-axis and Z-axis directions to the weight 31 is taken between terminals S0 and SY1 and between terminals S0 and SY2 and then between terminals S0 and SZ1 and between terminals S0 and SZ2, thus detecting the acceleration in X-axis and Z-axis directions. |
