Variable diameter orifice is required in many appli- cations e.g. smokestacks coal furnaces, liquid dispensing machines, wall fans, gas handling systems, pipes, vacuum chambers air valves, fluid control systems, ventilation sys- Tems, ducts, spot lights, holes of golf sports, photography nozzles, solid free fabrications and vacuum valves [1-17]. The need for variable diameter is to control the medium transfer through the orifice. In this abstract, a new design for a variable diameter orifice is introduced. Designing a variable diameter orifice is a challenging problem due to the need of circular geometry of the orifice opening. Many designs have been conducted to design a variable diameter orifice. However, the proposed designs are either have non circular opening or require a bulky size mechanism. In the proposed design, simplicity, size and actuation are our main concern.