Multi-Layer Piezoelectric Measuring Element, And Pressure Sensor Or Force Sensor Comprising Such A Measuring Element

摘要

A piezoelectric measuring element ( 9 ) consists of at least two piezoelectric crystals ( 1 ) showing a transversal effect for the measurement of axially acting forces and/or pressures as well as to a pressure or force sensor comprising said element. The crystals ( 1 ) with transversal effect having an opposite polarization ( 4 ) to each other are attached to each other by means of a lateral electrode ( 12 ). In this manner, if n crystals ( 1 ) are attached to each other, a single multi-layer measuring element ( 9 ) is obtained with a stability under load which is n-times that of an individual crystal. Preferably, the electrodes extend alternately into the two force-absorbing end faces ( 3 ) of the crystals. Such measuring elements can be fabricated from wafers ( 15 ) in a cost-effective manner. A compact multi-layer measuring element prepared in this way can be easily mounted in a sensor, particularly a force or pressure sensor, without the risk of inclination.