PURPOSE: To accurately detect an acceleration by applying oscillation between a rolling body which is guided by a guiding means and rolls according to the acceleration and the guiding means.

CONSTITUTION: The exciting current generated in the oscillating part 33 of a power source circuit 3 is outputted via a buffer 35 to a primary coil 13a. A magnetic field is generated in the coil 13a by this exciting current and an electric current is excited in a secondary coil 13b by this magnetic field. This current is outputted to a detecting circuit 5. The exciting current of a prescribed frequency is passed to the coil 13a from the circuit 3 and the oscillation circuit 71 of an oscillation driving part 7 receives the reference voltage of a reference voltage part 31 and passes the driving current superposed with the driving current on a prescribed bias voltage to a 1st electromagnet 15a. A phase inverting circuit 73 receives the driving current of the circuit 71, inverts the phase of the driving current and passes the driving current to the 2nd electromagnet 15b. A moving body 19 in the guide part 17 is reset to a reference position by the bias component among the driving currents and is oscillated by electromagnets 15a and 15b alternated by the prescribed frequency, by which the influence by the friction between the rolling body 19 and the guide part 17 is eliminated and the acceleration is accurately detected.