Component Allocation and Partitioning for a Dual Delivery Placement Machine

Consider a computer numerically controlled placement machine for populating printed circuit cards with surface mounted components, which features two carriers for the delivery of components to the placement heads. This parallel type of delivery system requires a systems analysis to determine: the number of tape reels of each component to be allocated; and to which of the two carriers each should be assigned along with the assignment of corresponding sets of tools. Factors that impinge on the development are: the flexibility of the machine's controller, and the fixturing for component feed vibratory and/or tape reel. The allocation models maximize the number of board completions attainable by a single allocation of components to the two carriers. This reduces the demand on the automated material handling system and the machine's operators for component replenishment. We consider the case where all components allocated are accessible and the case of a "static pick sequence." The partioning model minimizes the "dead time" with respect to operation balance, excess rotation and the number of required nozzle changes, so as to support a high throughput rate. The utilization of vibratory, ski slope type fixtures for the delivery of components is also addressed in an Appendix.