A Large Stroke Displacement Amplification Mechanism Of Composite Laminated Flexure Hinge

Piezoelectric ceramic actuator can realize the repeated positioning of nanometer level,but the displacement output stroke is small,and the flexible hinge displacement amplification mechanism is used to enlarge the output displacement.To increase the displacement magnification,it is necessary to use multi-level lever structure to produce multiple hinge nodes,which will lose a large output force of piezoelectric ceramics when deformation.The structure is a laborious lever structure,which will lose the output force of piezoelectric ceramics while amplifying the displacement.Therefore,with the increase of load,the output displacement will be reduced accordingly.In addition,the existing flexible hinges are single spring steel materials,which cause great deformation and stress consumption,and the bending part of hinge is too thin to be processed and easily damaged.In order to reduce the stress consumed in the deformation of flexible hinge,improve the load capacity of the system,and further increase the displacement magnification,the following two aspects are carried out.(1)A symmetrical multi-stage lever displacement amplifier is designed,its symmetrical topology is studied,theoretical magnification and stiffness are calculated.The output displacement,stress and natural frequency are analyzed and verified by ANSYS.(2)A kind of flexible hinge of laminated composite is proposed,and the related research is carried out in the aspects of magnification,structural parameters and assembly and fixing methods.The theoretical magnification of the first-stage lever laminated composite flexible hinge structure is 3.2 times,and the experimental results show that the displacement magnification of the flexible hinge with the composite material is 4.53 when there is no load,which is 16.8% higher than that of the full spring steel structure;When the load of 3.2Kg is added,the displacement magnification of the flexible hinge of the composite is 3.64,which is 5.0%higher than that of the full spring steel structure.ANSYS simulation of the displacement magnification of the multi-stage lever laminated composite flexible hinge can also effectively increase 5.2 times.The simulation results show that the multi-stage lever amplifier mechanism of laminated composite flexible hinge has the advantages of large displacement stroke,strong load capacity and easy processing,which provides scientific methods and reference for further improving the output displacement of piezoelectric ceramic driver.