Two end faces of the piezoelectric ceramic stack are fitted with ceramic end caps. You can choose a plane cap or hemispherical cap. When the load is along the translation axis of the driver, the plane end cap can achieve large force transfer because of its large contact area. The hemispherical end cap allows the drive to engage off-axis loads because the curved surface moves the force along the drive translation axis. The ceramic end cap not only helps to distribute the force applied by the load on the mounting surface of the stack, but also helps to guide the force along the movement axis of the drive.
The piezoelectric ceramic ring actuator can be a chip with bare electrodes, a chip with pre-connected wires, and a separate stack consisting of multiple chips bonded by epoxy resin and glass beads.