PURPOSE: To prevent a sensor chip from breaking by providing pedestals at both ends of the sensor chip and supporting both the ends.
CONSTITUTION: The pedestals 12 which are equal in height are provided at both the ends of the sensor chip 11 consisting of a semiconductor which is formed in a long and thin plate shape. A weight 13 is fitted to one end of an arm type base 14 made of a thin and long plate and the other end of the base 14 is coupled with the chip 11 at its lengthwise intermediate position. When acceleration operates, the chip 11 receives the force from the weight 13 and is strained, and an electric signal corresponding to the acceleration is obtained. At this time, the force which operates on the chip 11 from the side of the weight 13 is dispersed in the two directions where the pedestals 12 are present, so even when the force operates on the chip 1 as a bending or torsional force, the chip 11 is prevented from breaking.