Patent ID: 7775110
Filing Date: 2010-08-17
Classification: G01H

Abstract:
1. An ultrasonic sensor attached to a certain object, the sensor comprising: an ultrasonic detecting element that detects an ultrasonic wave, which is transmitted by an ultrasonic transmitting element that transmits the ultrasonic wave, and which is reflected by a detected body; an acoustic matching member that has a receiving surface that is adapted on a side of the certain object to be exposed to a space, in which the detected body exists, the receiving surface receiving the ultrasonic wave reflected by the detected body, the acoustic matching member transmitting the ultrasonic wave received by the receiving surface to the ultrasonic detecting element, which is attached to an opposing surface of the acoustic matching member opposite the receiving surface, the acoustic matching member being made of a material having an acoustic impedance larger than that of air and smaller than that of the ultrasonic detecting element; and an oscillation damping member that is disposed between an attachment portion and the acoustic matching member, the attachment portion being adapted for attaching the ultrasonic sensor to the certain object, the oscillation damping member damping transmission of oscillation from the certain object to the acoustic matching member, wherein the acoustic matching member has a contact face that contacts with the oscillation damping member, part of the contact face having one of a projection portion, which projects toward the oscillation damping member, and a recess portion, the oscillation damping member having a corresponding one of a recess portion and a projection portion, the corresponding one of the recess portion and the projection portion of the oscillation damping member having a shape for engaging with the one of the projection portion and the recess portion of the acoustic matching member.