PURPOSE: To improve the responsiveness of a capacitance type acceleration sensor which is used for air bag system or others.
CONSTITUTION: A plurality of grooves 7 crossing one another are provided on the electrode surface of a movable electrode 4 which is disposed between fixed electrodes 5 and 6 so that it is opposed to these electrodes through gaps, and the end part of each groove 7 is so opened as to face a space S outside a part of opposition between the movable electrode and the fixed electrodes. The grooves 7 may be provided also on the side of the fixed electrodes 5 and 6. By making the opening of each groove 7 face the outside space S, the ventilation of the inside and outside parts between the fixed electrodes and the movable electrode is made excellent, an air damper formed between the gaps of the electrodes when the movable electrode 4 operates is reduced, and a response speed of the movable electrode is increased.
SUZUKI KIYOMITSU
MATSUMOTO MASAHIRO
MIKI MASAYUKI
KOIDE AKIRA
| JPH02118456A | 1990-05-02 | |||
| JPH02271261A | 1990-11-06 | |||
| JPS60244864A | 1985-12-04 |
| US4825335A | 1989-04-25 |