Patent ID: 6326717
Filing Date: 2001-12-04
Classification: F02M,H01L

Abstract:
A piezoelectric actuator for actuating control valves or injection valves in motor vehicles, comprising an actuator body (10) in the form of a multilayered laminate made up of stacked layers of piezoelectric material with intervening metallic or electrically conductive layers that function as electrodes, which, the actuator body includes end faces between a bottom plate (11) oriented toward the valve and an opposing top plate (12), the end faces are elastically prestressed by means of two spring bands (13, 14; 33, 34) that are disposed in a longitudinal direction on opposite sides of the actuator body, the prestressing force of the springs is adjusted by adjusting means, the adjusting means includes an adjusting nut (16), which engages with an external thread (15) provided on a central, axial extension bolt (18) of the top plate (12) and which, depending on a screwed position of the adjusting nut, adjusts the prestressing force of the spring bands (13, 14; 33, 34).