A novel kinematic structure called as the Eclipse-IA is suggested for an application to the parallel machine tools. The stiffness enhancement design based on the Eclipse-IA structure is also introduced with its stiffness analysis for redundantly actuated parallel mechanisms. Relationship between the new structure and the stiffness properties including determinant and isotropy of the corresponding stiffness matrix is examined. Moreover, the design parameters are optimized to maximize the stiffness properties for the application of the Eclipse-IA as a multi-functional machine tool. By various simulation cases, the suggested parallel mechanism and the redundant actuation are verified to increase the stiffness properties against arbitrary external forces.