Patent ID: 6974294

Claim:
An article handling system for holding articles and moving selected articles individually from and/or to the article handling system, comprising: a plurality of vertically spaced article holding trays mounted for independent rotation about a common vertical axis, each tray having a plurality of discrete article holding locations; a tray rotating mechanism arranged to rotate a single selected tray; a pick-and-place mechanism having an article gripper mounted for vertical and horizontal movement such that the gripper can reach any article holding location on any selected tray; and a controller coordinating rotation of the selected tray and movement of the gripper such that the gripper can move to and from the selected article holding location, wherein each tray has a rotational home position and a peripheral notch sized to accommodate the gripper when it moves vertically to or from the selected tray, the home positions of the trays being coincident and defined by rotational positions in which all notches are aligned wherein the tray rotating mechanism comprises a rotatable vertical spindle, and each tray has an open-sided hub open to the peripheral notch and configured to partially surround the vertical spindle, each tray being removably mounted for engagement by the vertical spindle by horizontal movement of the tray relative to the vertical spindle, and wherein the hub has at least one keyway, and the vertical spindle has at least one movable key selectively positionable to engage the keyway of the selected tray so as to enable rotation of only the selected tray.