To ensure a constant power against acceleration of a certain intensity to a low frequency region by connecting a capacitor to the output terminal of a mechanical-electrical converter in parallel and attain small-sizing and cost reduction of the device.
A mechanical-electrical converter 1 having a piezoelectric element 2 is contained in a vessel constituted of a vessel base part 10a and a vessel lid part 10b. Also, a capacitor 12 is connected in parallel to the output terminal of the mechanical-electrical converter 1 and by the two end voltage of the capacitor 12, the acceleration added to the mechanical-electrical converter 1 is detected. The capacitor can be worked in the same effect as the electrostatic capacity of the mechanical-electrical converter 1 is increased, and so cut-off frequency can be decreased. By that, a constant intensity output against the acceleration of the certain intensity to low frequency region can be obtained. As the number of parts in a signal processing circuit can be reduced, reduction of mounting area and small-sizing of the impact detection device and the like can be attained.
SUGIMOTO MASAHITO
TOMITA YOSHIHIRO
KAWASAKI OSAMU
| JPH0720144A | 1995-01-24 | |||
| JPH0560782A | 1993-03-12 | |||
| JPH08107328A | 1996-04-23 | |||
| JPH0955638A | 1997-02-25 | |||
| JPH08153915A | 1996-06-11 | |||
| JPH08162686A | 1996-06-21 |
| EP0768532A2 | 1997-04-16 |