抄録
A new surface mount system with a parallel arrangement of miniature manipulators was proposed for use in system down sizing. The miniature manipulator consists of a molded pantograph mechanism, which is composed of large deflective hinges and links, both made of the same materials. The complex and dynamic loads, that is, a combination stress of bending, tensile, compression and shearing stresses, occurs on each hinge in the pantograph mechanism. In these stresses, a hypothesis that bending and tensile stresses are the major factors in the fatigue damage of hinges is set up. On the hypothesis, tensile-compressive and bending conditions with hinge specimen as a fatigue test are carried out. The hinge specimen is made by the injection molding machine, and its material is polypropylene (PP) or the combination of PP and ethylene-propylene-rubber (EPT). By the fatigue test, the durability of hinge made of each material and the damage advance inside of the hinge are investigated experimentally.