Actuating drive for e.g. membrane valve, has two curved spiral springs made from same or different material, and tie-rod provided for pre-stressing springs and supported at angular point of springs

摘要

The drive has an actuating unit (2) in the form of electrostrictive or magnetostrictive actuator, and a mechanical path enlargement system driven by the actuating unit. A lever arm (1) is arranged at a curved spiral spring (5), and another curved spiral spring (6) has ends that are supported on a base-inner side of the former spring. A tie-rod (3) is provided for pre-stressing the springs and is supported at an angular point of the springs. A frame is arranged at the spring or at the tie-rod, where the springs are made from same or different material.