High speed variable count mechanical stacker

Abstract

A pair of closed loop chains running in parallelism have uniformly spaced apart paddles on them for transporting an article such as a pad between each paddle to a pad ejection station. A shaft orbits about an axis which is parallel to the direction in which the paddle conveyor is moving. The shaft carries a plurality of ejector rods which are mounted on a sleeve that is slidable reversibly axially on the orbiting shaft. After the orbiting rods collectively eject a series of pads from the paddles, the shaft continues its orbital movement until it reaches the back side of the pads again. While the rods are passing through the paddles to eject the number of pads composing a stack, the sleeve on the orbiting shaft is translated axially in the same direction and at the same speed as the paddle conveyor is moving. The sleeve is shifted by having a cam follower thereon come into contact with a stationary cam when the rods begin their passage through the spaces between the paddles. When rods clear the spaces between the paddles, a spring restores the rods to their initial position. The orbiting shaft can be caused to dwell in its orbit to allow a selected number of pads to arrive on the conveyor at the ejection station before orbiting the rods to cause ejection of the articles is initiated.