US Patent 9239337 Ultrasonic transducer for use in a fluid medium

An ultrasonic transducer for use in a fluid medium is proposed. The ultrasonic transducer includes at least one transducer core which has at least one acoustic/electric transducer element, in particular a piezoelectric transducer element. The ultrasonic transducer furthermore includes at least one housing, at least one housing opening being at least partially sealed against the fluid medium with the aid of a sealing film which is connected to the transducer core. The sealing film has at least one expansion deformation which is configured to permit a relative movement between the transducer core and the housing.