Development of a New Geneva Mechanism With Improved Kinematic Characteristics

Abstract

A Geneva wheel with curved slots is proposed as an intermittent rotary motion generating mechanism. The proposed mechanism has vastly improved kinematic characteristics. Changing the slot shape from a straight radial line to a curved line results in the elimination of shock loading at the beginning and end of the motion cycles and reduces the wheel peak velocity and peak acceleration values, making this new mechanism well suited for high speed applications. In addition, the designer can freely select the dwell to motion time ratio of the wheel. Furthermore, this paper presents a great improvement to the design of a curve slotted Geneva wheel, by introducing an offset to the curved slot. The offsetting technique, which does not alter the kinematic characteristics of the mechanism, modifies the shape of the slot. A suitable offset can yield a curved slot acceptable for practical applications. This development provides an important tool for designing a simple, practical and reliable intermittent motion generating mechanism with excellent kinematic characteristics.