Ultrasonic transmitting and receiving device for use as ultrasonic level sensor, has adhesive layer having specific mechanical shear stress firmness, such that mechanical oscillations are transferred between piezoelement and coupling plate

摘要

The device has a ceramic sound coupling plate (1) in which a piezoelement (2) is arranged on a broadside (1'). The piezoelement comprises an adhesive layer for transferring mechanical longitudinal oscillations. The piezoelement is connected with conductive strips (3, 4) arranged on the broadside of the plate. The adhesive layer has a thickness, which is smaller than quarter of wavelength of lowest resonant frequency of the device and has a specific mechanical shear stress firmness, such that mechanical transverse oscillations are transferred between the piezoelement and the plate. An independent claim is also included for a method for manufacturing an ultrasonic transmitting and receiving device.