Method and apparatus for storing or retrieving items

Abstract

A method and apparatus are provided for storing and retrieving items to/from a plurality of destinations areas. A storage and retrieval system stores and retrieves items as needed and transfer items from storage locations to transfer locations. A separate picking system conveys the items from the transfer locations to a picking station or an input out station so that the item can be selected.

1 . (canceled) 
     
     
         2 . A method for processing a plurality of items with a material handling system having a plurality of destination areas, comprising the steps of:
 controlling the movement of a plurality of independently operable delivery vehicles to simultaneously drive the delivery vehicles within the material handling system wherein each of the delivery vehicles has a first transfer mechanism, comprising the steps of:
 loading a first item onto a first of the plurality of delivery vehicles by operating the first transfer mechanism of the first delivery vehicle to load the first item onto the first delivery vehicle; 
 driving the first delivery vehicle vertically and horizontally along a path to a first of the plurality of destination areas; 
 operating the first transfer mechanism to transfer the first item from the first delivery vehicle to the first destination area; 
 loading a second item onto a second of the plurality of delivery vehicles by operating the first transfer mechanism of the second delivery vehicle to load the second item onto the second delivery vehicle; 
 driving the second delivery vehicle vertically and horizontally along a path to the first destination area; 
 operating the first transfer mechanism of the second delivery vehicle to transfer the second item from the second delivery vehicle to the first destination area to accumulate the first and second items in the first destination area; 
   controlling a plurality of independently operable retrieval vehicles to selectively retrieve items accumulated in the destination areas wherein the step of selectively retrieving items accumulated in the destination areas comprises the steps of;   driving a first of the plurality of retrieval vehicles to the first destination area;   operating a second transfer mechanism that is configured differently than the first transfer mechanism to load the first item and the second item onto the first retrieval vehicle; and   driving the first retrieval vehicle away from the first destination area to drive the first item and the second item away from the first destination area.   
     
     
         3 . The method of  claim 2  comprising the step of operating the second transfer mechanism of the first retrieval vehicle to transfer the first item and the second item into a rack of storage locations. 
     
     
         4 . The method of  claim 2  comprising the step of transferring the first item and the second item off the first retrieval vehicle. 
     
     
         5 . The method of  claim 2  wherein the step of driving the first delivery vehicle comprises maintaining the horizontal orientation of the first delivery vehicle as the first delivery vehicle drives from a vertical direction to a horizontal direction. 
     
     
         6 . The method of  claim 2  wherein the step of driving the first delivery vehicle comprises driving the first delivery vehicle around a loop having a vertical leg and a horizontal leg. 
     
     
         7 . The method of  claim 6  wherein the step of driving the first retrieval vehicle comprises the step of driving the first retrieval vehicle along a route that is different than the loop along which the first vehicle is driven. 
     
     
         8 . The method of  claim 7  wherein the loop comprises a first track and the route comprises a second track that is separate from the first track. 
     
     
         9 . The method of  claim 2  wherein each delivery vehicle comprises two pairs of opposing wheels and the material handling system comprises a front track for guiding a first pair of the opposing wheels and rear track for guiding a second pair of the opposing wheels wherein an aisle is formed between the front track and the rear track, wherein the step of driving the first delivery vehicle comprises driving the first delivery vehicle within the aisle to deliver the first item to the first destination area. 
     
     
         10 . The method of  claim 2  wherein the step of driving the first delivery vehicle comprises driving the first delivery vehicle vertically upwardly. 
     
     
         11 . The method of  claim 2  wherein the first transfer mechanism comprises a conveyor belt and the step of actuating a first transfer mechanism comprises driving the conveyor belt to displace the first item onto the conveyor belt. 
     
     
         12 . A method for processing a plurality of items with a material handling system having a plurality of destination areas and a plurality of independently operable delivery vehicles, wherein the method comprises the steps of:
 loading an item onto one of the delivery vehicles, wherein the step of loading an item comprises the steps of:
 stopping the delivery vehicle at a loading station; and 
 operating a transfer mechanism to load an item onto the delivery vehicle while the delivery vehicles is stopped at the loading station; 
   driving the delivery vehicle vertically and horizontally along a path to one of the destination areas after the item is loaded at the input station;   transferring the item from the delivery vehicle to the destination area;   accumulating a plurality of items at the destination areas by repeating the steps of loading, driving and transferring a plurality of times;   controlling a plurality of independently operable retrieval vehicles to selectively retrieve items accumulated in the destination areas wherein the step of selectively retrieving items accumulated in the destination areas comprises operating a loading mechanism that is configured differently than the transfer mechanism; and   displacing the retrieval vehicles to displace the selectively retrieved items away from the destination areas.   
     
     
         13 . The method of  claim 12  wherein the step of driving comprises maintaining the horizontal orientation of the delivery vehicle as the delivery vehicle drives from a vertical direction to a horizontal direction. 
     
     
         14 . The method of  claim 13  wherein the step of driving comprises driving the delivery vehicle around a loop having a vertical leg and a horizontal leg. 
     
     
         15 . The method of  claim 14  wherein the step of displacing the retrieval vehicles comprises driving the retrieval vehicles along a route that is separate from the loop. 
     
     
         16 . The method of  claim 15  wherein the loop comprises a first track and the route comprises a second track that is separate from the first track, wherein the step of driving the delivery vehicle around the loop comprises driving the delivery vehicle along the first track and the step of displacing the retrieval vehicles comprises displacing the retrieval vehicles along the second track. 
     
     
         17 . The method of  claim 12  wherein the step of driving the delivery vehicle comprises driving the delivery vehicle vertically upwardly. 
     
     
         18 . The method of  claim 12  wherein the step of operating a transfer mechanism comprises the step of actuating a transfer mechanism that forms part of the delivery vehicle. 
     
     
         19 . The method of  claim 18  wherein the transfer mechanism comprises a conveyor belt and the step of actuating a transfer mechanism comprises driving the conveyor belt to displace the item on the conveyor belt. 
     
     
         20 . A material handling system for processing a plurality of items, comprising:
 a plurality of destination areas;   a plurality of independently operable delivery vehicles wherein each of the delivery vehicles has a first transfer mechanism;   a plurality of independently operable retrieval vehicles wherein each of the retrieval vehicles comprises a second transfer mechanism that is configured differently than the first transfer mechanism;   a central controller configured to control the operation of the delivery vehicles and the retrieval vehicles, wherein the central controller is configured to perform the steps of:
 controlling the movement of the delivery vehicles to simultaneously drive the delivery vehicles within the material handling system, comprising the steps of:
 loading a first item onto a first of the plurality of delivery vehicles by operating the first transfer mechanism of the first delivery vehicle to load the first item onto the first delivery vehicle; 
 driving the first delivery vehicle vertically and horizontally along a path to a first of the plurality of destination areas; 
 operating the first transfer mechanism to transfer the first item from the first delivery vehicle to the first destination area; 
 loading a second item onto a second of the plurality of delivery vehicles by operating the first transfer mechanism of the second delivery vehicle to load the second item onto the second delivery vehicle; 
 driving the second delivery vehicle vertically and horizontally along a path to the first destination area; 
 operating the first transfer mechanism of the second delivery vehicle to transfer the second item from the second delivery vehicle to the first destination area to accumulate the first and second items in the first destination area; 
 
 controlling the retrieval vehicles to selectively retrieve items accumulated in the destination areas wherein the step of selectively retrieving items accumulated in the destination areas comprises the steps of:
 driving a first of the retrieval vehicles to the first destination area; 
 operating the second transfer mechanism of the first retrieval vehicle to load the first item and the second item onto the first retrieval vehicle; and 
 driving the first retrieval vehicle away from the first destination area to drive the first item and the second item away from the first destination area. 
 
   
     
     
         21 . The system of  claim 20  wherein the central controller is configured to operate the second transfer mechanism of the first retrieval vehicle to transfer the first item and the second item into a rack of storage locations. 
     
     
         22 . The system of  claim 20  wherein the first delivery vehicle is configured to maintain the horizontal orientation of the first delivery vehicle as the first delivery vehicle drives from a vertical direction to a horizontal direction. 
     
     
         23 . The system of  claim 20  wherein the central controller is configured to drive the first delivery vehicle around a loop having a vertical leg and a horizontal leg. 
     
     
         24 . The system of  claim 23  wherein the central controller is configured so that the step of driving the first retrieval vehicle comprises the step of driving the first retrieval vehicle along a route that is different than the loop along which the first vehicle is driven. 
     
     
         25 . The method of  claim 24  wherein the loop comprises a first track and the route comprises a second track that is separate from the first track. 
     
     
         26 . The method of  claim 25  wherein each delivery vehicle comprises two pairs of opposing wheels and the first track comprises a front track for guiding a first pair of the opposing wheels and a rear track for guiding a second pair of the opposing wheels wherein an aisle is formed between the front track and the rear track, wherein the step of driving the first delivery vehicle comprises driving the first delivery vehicle within the aisle to deliver the first item to the first destination area. 
     
     
         27 . The method of  claim 20  wherein the central controller is configured so that the step of driving the first delivery vehicle comprises driving the first delivery vehicle vertically upwardly. 
     
     
         28 . The method of  claim 20  wherein the first transfer mechanism comprises a conveyor belt and the step of actuating a first transfer mechanism comprises driving the conveyor belt to displace the first item onto the conveyor belt.