| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a high shock resistant ultrasonic sensor with which a piezoelectric element is hardly separated and mass production can be performed easily. <P>SOLUTION: An ultrasonic sensor 201 is provided with a piezoelectric element 21 and a bumper 22 which is an ultrasonic transmission/reception wave member to which the piezoelectric element 21 is attached, and a flexible member 23 and an ultrasonic transmission member 24 are arranged between the piezoelectric element 21 and the bumper 22. The piezoelectric element 21 is provided with an electrode formed in the upper and lower faces, and it spreads and vibrates in the radial direction by applying an alternation voltage. The ultrasonic transmission member 24 has a smaller Young's modulus than the bumper 22 and the piezoelectric element 21, and transmits the elastic wave which is generated in the piezoelectric element 21 to the bumper 22. Since the bumper 22 flexural-vibrates in a comparatively wide range, the narrow directivity and the high sensitivity characteristics are obtained. <P>COPYRIGHT: (C)2012,JPO&INPIT |
