Magnetostrictive actuator with differential displacement amplification mechanism
In light of the contradiction between stroke and accuracy of current actuators, a high precision, large displacement actuator was designed. Rare earth giant magnetostrictive material was used as the driving source and the displacement differential amplification was based on a flexure hinge. A magnetic circuit and driving magnetic field was designed with the characteristics of magnetostrictive drive. The axial pre-pressure of the magnetostrictive rod was supported by a cylindrical helical spring and a displacement amplification mechanism. A new type of differential amplification device was projected by the flexible hinge. The convex desktop splint fixed displacement amplification mechanism was adopted to enlarge the magnetostrictive’s small displacement. After the actuator prototype was manufactured and the test platform was established, the output characteristics and amplification mechanism performance were analyzed. Results showed that under the condition of 0 to 4 input current, the maximum displacement was 158.4 μm and the magnification was 7.14.