Abstract: An arrangement for handling stacks of articles, each article having a predetermined height dimension, employs a stack guide for maintaining the stack of articles in stacked alignment, and an elevator for rasing and lowering the stack guide. A retractable support is coupled to the stack guide for supporting the articles and selectably releasing a lowermost one of the articles, or in the alternative, picking up an article, such that the article is added onto the bottom of the stack. The retractable supports extend along the length of the articles and are rotatable between engaged and disengaged positions. A linear actuator is coupled to the retractable supports by operation of links and effects the rotation between the engaged and disengaged positions. A limiter assembly determines the lowermost limit of the elevator, and also defines a predetermined extent of upward travel, which predetermined extent corresponds to the height of an article of the stack.

Abstract: A clamping arrangement employs a rotatable element, such as a ball, driven by a cam to apply a biasing force to an article desired to be clamped. The ball is contained within a housing having first and second through-holes arranged substantially orthogonal to one another. An elongated cam enters through one of the through-holes, and urges the ball to protrude through the other through-hole. The ball is larger than the through-hole through which it protrudes, and therefore does not exit the housing. In one embodiment, the cam is urged into communication with the ball by the application of air pressure to a pneumatic cylinder. The air pressure can be controlled to ensure that the biasing force applied by the ball is applied gently and resiliently to avoid jarring the article to be clamped, and displacing its contents. A position sensor is employed to provide an indication of the location of the pneumatic piston.

Abstract: A handler/sorter for articles such as the trays of integrated circuit chips is provided with an unstacking elevator system, an inspection station, a sorting station for repopulating the tray with non-defective integrated circuit chips, and an output station. The output station has a stacking elevator which is essentially the mirror image of the unstacking elevator at the input station, reducing the number of different parts. The elevators employ pneumatic or linear motor drives which gently place the trays on the conveyor shuttles, without rattling the integrated circuit chips. In an optical inspection embodiment, a focussing elevator is provided at the inspection station. The focussing elevator operates in response to focus control signals issued by a scanning camera system. Transportation between the respective stations is provided by a pair of conveyor shuttles which employ linear motors.