Minimizing the cycle time in multiple-dwell cams

Abstract

Presented in this article are closed-form kinematic equations that give the minimum cycle time for multiple-dwell cam-follower systems subject to acceleration and jerk constraints set by the user. Cam-driven machines are used extensively in manufacturing because of their low cost, great precision and high production rates when compared with alternatives. Since they are frequently used in mass production operations, there is a need for minimizing their cycle time to increase manufacturing throughput and reduce capital costs for machines and facilities. Their widespread use means that there is the potential for significant improvement in overall manufacturing efficiency. The incorporation of acceleration and jerk limits in the kinematic formulation ensures minimal cycle time without compromising the operational limits of the manufacturing machines. The equations are given in a form suitable for spreadsheet or equation-solver programs, making it easy for the cam designer to generate an arbitrary number of data points for cam manufacturing. Multiple-dwell cams are particularly well suited for manufacturing operations; therefore, the intended audience of this paper is cam designers in the manufacturing sector.

Keywords

Cam design cam optimization production system optimization

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