| 摘要 |
The invention relates to a device for determining and/or monitoring a process variable of a medium, comprising an oscillatable unit (1) which is fixed to a membrane (5), a transmitter/receiver unit (6) which excites the membrane (5) and the oscillatable unit (1) in order to cause oscillations and which receives said vibrations from the oscillatable unit (1), said transmitter/receiver unit (6) being embodied in the form of a disk-shaped piezo-electric element (15), also comprising a control /evaluation unit (10) which monitors and/or determines the process variable according to the oscillations of the oscillatable unit (1). According to the unit (1), the disk-shaped piezo-electric element (15) comprises segments (18) which are substantially polarized in an opposite direction, and at least two oppositely polarized electrodes (20) are arranged on the side (16) of the disk-shaped piezo-electric element (15) which faces away from the membrane (5). |
