Article handling system and method

Abstract

An article handling system and method for holding articles and moving selected articles individually from and/or to the article handling system. A plurality of vertically spaced article holding trays are mounted for independent rotation, each tray having a plurality of discrete article holding locations. A tray rotating mechanism is arranged to rotate a single selected tray, while a pick-and-place mechanism has an article gripper mounted for vertical and horizontal movement such that the gripper can reach any article holding location on any selected tray. A controller coordinates rotation of the selected tray and movement of the gripper such that the gripper can move to and from the selected article holding location. The handling system is especially useful as part of an automated system for processing multiple specimens of biological fluid in separate vials.

1 . 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.    
   
   
       2 . An article handling system according to  claim 1 , 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.  
   
   
       3 . An article handling system according to  claim 2 , wherein the controller enables rotation of the selected tray only when all other trays are in their home positions.  
   
   
       4 . An article handling system according to  claim 2 , 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.  
   
   
       5 . An article handling system according to  claim 4 , further comprising a shelf at each tray location for supporting the tray during mounting thereof.  
   
   
       6 . An article handling system according to  claim 5 , further comprising guides at each tray location that ensure proper tray insertion and positioning during mounting thereof.  
   
   
       7 . An article handling system according to  claim 1 , wherein each article holding location has an indexing characteristic that mates with a complementary indexing characteristic on the article to ensure proper orientation of the article relative to the tray.  
   
   
       8 . An article handling system according to  claim 7 , wherein the indexing characteristic on the tray comprises a projection.  
   
   
       9 . An article handling system according to  claim 1 , wherein each article holding location comprises a recess sized to receive an article.  
   
   
       10 . An article handling system according to  claim 9 , wherein each recess has an indexing characteristic that mates with a complementary indexing characteristic on the article to ensure proper orientation of the article relative to the tray.  
   
   
       11 . An article handling system according to  claim 10 , wherein the indexing characteristic of the recess comprises a projection in the recess that supports and indexes the article.  
   
   
       12 . An article handling system according to  claim 11 , wherein each recess has an opening in its bottom.  
   
   
       13 . An article handling system according to  claim 1 , wherein the trays are stackable when removed from the handling system.  
   
   
       14 . An article handling system according to  claim 13 , wherein each tray has a plurality of upstanding posts adapted to engage the underside of and support a superposed tray.  
   
   
       15 . An article handling system according to  claim 14 , wherein each tray has stacking recesses on its underside that mate with the tops of the posts.  
   
   
       16 . An article handling system according to  claim 1  or  claim 3 , wherein the tray rotating mechanism comprises a rotatable vertical spindle and each tray has a hub sized to receive the vertical spindle, the hub having at least one keyway and the vertical spindle having 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.  
   
   
       17 . An article handling system according to  claim 3 , wherein the pick-and-place mechanism comprises an elevator carriage with a laterally extending arm carrying the gripper, the elevator carriage guided vertically adjacent the trays with the gripper extending into the notches of the trays above the selected tray.  
   
   
       18 . An article handling system according to  claim 17 , wherein the arm is pivoted to the elevator carriage for horizontal movement toward and away from the selected tray.  
   
   
       19 . An article handling system according to  claim 18 , wherein a vertical lead screw driven by a stepper motor effects vertical movement of the elevator carriage.  
   
   
       20 . An article handling system according to  claim 19 , wherein a horizontal lead screw driven by a stepper motor effects horizontal movement of the arm and the gripper.  
   
   
       21 . A method of individually placing an article on, or removing an article from, one of a plurality of vertically spaced trays mounted for independent rotation about a common vertical axis, each tray having a plurality of discrete article holding locations and a peripheral notch sized to accommodate a gripper mounted for vertical and horizontal movement to reach any article holding location on any selected tray, the method comprising: 
 selecting an article holding location on a selected tray;    moving the gripper downwardly through the notches of the trays above the selected tray;    rotating the selected tray and horizontally moving the gripper sufficiently to enable the gripper to access the selected article holding location; and    releasing an article to the selected article holding location if vacant, or grasping an article from the selected article holding location if occupied.    
   
   
       22 . A method according to  claim 21 , further comprising reversing the recited horizontal and vertical movement of the gripper.