| 摘要 |
PURPOSE: A supersonic wave sensor detecting obstacle is provided to improve the near obstacle detection property by reducing remaining vibration of case by suppressing increase of echo period maximally under severe temperature change. CONSTITUTION: A cylindrical case(11) forms the bottom surface. The piezo ceramic element(12) is adhered to the bottom surface of the case inside. The acoustic absorbing material(13) is located on the piezo ceramic element. The first filler(18) is formed around the piezo ceramic element and the acoustic absorbing material. The temperature compensating capacitor(14) is located on the acoustic absorbing material. The reinforcing substrate(15) is adhered on one side of the temperature compensating capacitor. The second filler(19) surrounds the reinforcing substrate and the temperature compensating capacitor. |
